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Immobilization of activated sludge using improved polyvinyl alcohol (PVA) gel 被引量:35
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作者 ZHANG Li-sheng WU wei-zhong WANG Jian-long 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1293-1297,共5页
The microbial immobilization method using polyvinyl alcohol (PVA) gel as an immobilizing material was improved and used for entrapment of activated sludge. The oxygen uptake rate (OUR) was used to characterize the... The microbial immobilization method using polyvinyl alcohol (PVA) gel as an immobilizing material was improved and used for entrapment of activated sludge. The oxygen uptake rate (OUR) was used to characterize the biological activity of immobilized activated sludge. Three kinds of PVA-immobilized particles of activated sludge, that is, PVA-boric acid beads, PVA-sodium nitrate beads and PVA-orthophosphate beads were prepared, and their biological activity was compared by measuring the OUR value. The bioactivity of both autotrophic and heterotrophic microorganisms of activated sludge was determined using different synthetic wastewater media (containing 250 mg/L COD and 25 mg/L NH4^+ -N). The experimental results showed that the bioactivity and stability of the three kinds of immobilized activated sludge was greatly improved after activation. With respect of the bioactivity and the mechanical stability, the PVA-orthophosphate method may be a promising and economical technique for microbial immobilization. 展开更多
关键词 IMMOBILIZATION biological activity oxygen uptake rate (OUR) polyvinyl alcohol (PVA)
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Early diagnosis and treatment of severe acute cholangitis 被引量:22
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作者 wei-zhong Zhang Yi-Shao Chen Jin-wei Wang Xue-Rong Chen Department of Surgery,Huangyan First Hospital,Huangyan 318020,Zhejiang Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第1期150-152,共3页
AIM: To investigate the diagnostic standard for earlyidentification of severe acute cholangitis in order to lowerthe incidence of morbidity and mortality rate.METHODS: A diagnostic standard was proposed in thisstudy a... AIM: To investigate the diagnostic standard for earlyidentification of severe acute cholangitis in order to lowerthe incidence of morbidity and mortality rate.METHODS: A diagnostic standard was proposed in thisstudy as follows: documented biliary duct obstruction byultrasound or computerized tomography or other imagingtools with the manifestation of systemic inflammatoryresponse syndrome (SIRS). The surgical proceduresincluded emergency common bile duct exploration with Ttube insertion or cholecystostomy with secondary commonbile duct exploration. And incidence of postoperativemultiple organ dysfunction syndrome (MODS), duration ofsystemic inflammatory response and hospital mortality wereanalyzed.RESULTS: Fourty - three patients conforming to thediagnostic standard described above were employed in thisstudy. 1 patient was admitted in acutely ill condition andcomplicated with acute relapse of chronic bronchitis,cholecystostomy procedure was performed but the patientwas complicated with postoperative acute lung injury whiclwas treated by assisted mechanical ventilation for 5 d; 2 wllater, two- stage common bile duct Exploration and T tubeinsertion were performed. The remaining 42 patientsunderwent primary common bile duct exploration and T tubeinsertion, 1 developed acute lung injury and recovered 3 dlater, 2 patients developedl acute renal dysfunction, 1 ofwhich recovered 2 d later and the other died on d 4. For allpatients, the postoperative systemic inflammatory responsepersisted for 2 to 8 d with median of 3 d.CONCLUSION: Early diagnosis of severe acute cholangitiscan be made using this diagnostic standard, furtherdevelopment of systemic inflammatory response could beprevented and incidence of MODS as well as hospitalmortality decreased. 展开更多
关键词 急性重症胆管炎 早期诊断 治疗 多器官功能衰竭
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CPPI投资组合保险策略的实证分析 被引量:15
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作者 杜少剑 陈伟忠 +3 位作者 DU Shao-jian CHEN wei-zhong 《财贸研究》 北大核心 2005年第1期36-40,共5页
本文首先简要介绍了CPPI投资组合保险策略,通过采用上证综合指数,对多头、空头和震荡三个时期,以及不同的最低保险额和乘数,对CPPI策略进行历史数据实证模拟,并与B&H策略做比较,发现CPPI策略在我国证券市场是能够起到有效保险作用的.
关键词 保险 投资组合 策略 低保 上证综合指数 证券市场 实证分析 乘数 时期 中国
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Effects of electroacupuncture at Zusanli(ST36) on inflammatory cytokines in a rat model of smokeinduced chronic obstructive pulmonary disease 被引量:22
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作者 Wen-ye Geng Zi-bing Liu +7 位作者 Na-na Song Gui-hong Zhang wei-zhong Jin Wang Zhou Li Li Yin-xiang Cao Da-nian Zhu Lin-lin Shen 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第3期213-219,共7页
OBJECTIVE: Improvement in lung function was reported after acupuncture treatment of chronic obstructive pulmonary disease (COPD), but little is known about the underlying mechanisms. Because an immune response imba... OBJECTIVE: Improvement in lung function was reported after acupuncture treatment of chronic obstructive pulmonary disease (COPD), but little is known about the underlying mechanisms. Because an immune response imbalance could be seen in COPD, we hypothesize that electroacupuncture (EA) may play a role in regulating inflammatory cytokines and contribute to lung protection in a rat model of smoke-induced COPD. METHODS: A COPD model using male Sprague-Dawley rats exposed to cigarette smoke was established. The rats were randomly divided into four groups (control, sham, COPD, and COPD plus EA), and COPD model was evaluated by measuring pulmonary pathological changes and lung function. EA was applied to the acupuncture point Zusanli (ST36) for 30 min/d for 14 d in sham and COPD rats. Bronchoalveolar lavage fluid (BALF) was used to measure levels of tumor necrosis factor-a (TNF-a), interleukin-113 (IL-113), and malonaldehyde (MDA). RESULTS: Compared with the control rats, COPD rats had significant changes in lung resistance (R,) and lung compliance (C,) (both P〈0.01), bronchi and bronchiole airway obstruction (P〈0.01), and levels of MDA, TNF-α, and IL-1β(P〈0.01). There were no significant differences between the control and the sham groups. Compared with the COPD rats, the COPD plus EA rats had decreased R, and increased CL (both P〈0.05), and reduced bronchi and bronchiole airway obstruction (P〈0.05, P〈0.01, respectively), while levels of TNF-α, IL-1β, and MDA in BALF were lowered (P〈0.05 and P〈0.01, respectively). However, TNF-α and IL-1β levels of the EA group rats remained higher than those of the control group (P〈0.05). CONCLUSION: EA at ST36 can reduce lung injury in a COPD rat model, and beneficial effects may be related to down-regulation of inflammatory cytokines. The anti-inflammatory and antioxidant effects may prolong the clinical benefit of EA. 展开更多
关键词 chronic obstructive pulmonary disease ELECTROACUPUNCTURE ANTI-INFLAMMATORY ANTIOXIDANT Zusanli (ST36) rats
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Human umbilical cord mesenchymal stem cells derived from Wharton's jelly differentiate into insulin-producing cells in vitro 被引量:19
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作者 WANG Hong-wu LIN Li-min +5 位作者 HE Hong-yan YOU Fang LI wei-zhong HUANG Tian-hua MA Gui-xia MA Lian 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第10期1534-1539,共6页
Background Islet transplantation is an effective way of reversing type Ⅰ diabetes. However, islet transplantation is hampered by issues such as immune rejection and shortage of donor islets. Mesenchymal stem cells ca... Background Islet transplantation is an effective way of reversing type Ⅰ diabetes. However, islet transplantation is hampered by issues such as immune rejection and shortage of donor islets. Mesenchymal stem cells can differentiate into insulin-producing cells. However, the potential of human umbilical cord mesenchymal stem cells (huMSCs) to become insulin-producing cells remains undetermined.Methods We isolated and induced cultured huMSCs under islet cell culture conditions. The response of huMSCs were monitored under an inverted phase contrast microscope. Immunocytochemical and immunofluorescence staining methods were used to measure insulin and glucagon protein levels. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect gene expression of human insulin and PDX-1. Dithizone-staining was employed to determine the zinc contents in huMSCs. Insulin secretion was also evaluated through radioimmunoassay.Results HuMSCs induced by nicotinamide and β-mercaptoethanol or by neurogenic differentiation 1 gene (NeuroD1)transfection gradually changed morphology from typically elongated fibroblast-shaped cells to round cells. They had a tendency to form clusters. Immunocytochemical studies showed positive expression of human insulin and glucagon in these cells in response to induction. RT-PCR experiments found that huMSCs expressed insulin and PDX-1 genes following induction and dithizone stained the cytoplasm of huMSCs a brownish red color after induction. Insulin secretion in induced huMSCs was significantly elevated compared with the control group (t=6.183, P〈0.05).Conclusions HuMSCs are able to differentiate into insulin-producing cells in vitro. The potential use of huMSCs in βcell replacement therapy of diabetes needs to be studied further 展开更多
关键词 human umbilical cord mesenchymal stem cells DIFFERENTIATION insulin-producing cells
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Hyperbaric oxygen therapy improves the effect of keloid surgery and radiotherapy by reducing the recurrence rate 被引量:16
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作者 Ke-xin SONG Shu LIU +5 位作者 Ming-zi ZHANG wei-zhong LIANG Hao LIU Xin-hang DONG You-bin WANG Xiao-jun WANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2018年第11期853-862,共10页
Objective: Keloids are exuberant cutaneous scars that form due to abnormal growth of fibrous tissue fol- lowing an injury. The primary aim of this study was to assess the efficacy and mechanism of hyperbaric oxygen t... Objective: Keloids are exuberant cutaneous scars that form due to abnormal growth of fibrous tissue fol- lowing an injury. The primary aim of this study was to assess the efficacy and mechanism of hyperbaric oxygen therapy (HBOT) to reduce the keloid recurrence rate after surgical excision and radiotherapy. Methods: (1) A total of 240 patients were randomly divided into two groups. Patients in the HBOT group (O group) received HBOT after surgical excision and radiotherapy. Patients in the other group were treated with only surgical excision and radiotherapy (K group). (2) Scar tissue from recurrent patients was collected after a second operation. Hematoxylin and eosin (H&E) staining was used to observe keloid morphology. Certain inflammatory factors (interleukin-6 (IL-6), hypoxia-inducible factor-1α (HIF-1α), tumor necrosis factor-α (TNF-α), nuclear factor KB (NF-κB), and vascular endothelial growth factor (VEGF)) were measured using immunohistochemical staining. Results: (1) The recurrence rate of the O group (5.97%) was significantly lower than that of the K group (14.15%), P〈0.05. Moreover, patients in the O group reported greater satisfaction than those in the K group (P〈0.05). (2) Compared with the recurrent scar tissue of the K group, the expression levels of the inflammatory factors were lower in the recurrent scar tissue of the O group. Conclusions: Adjunctive HBOT effectively reduces the keloid recurrence rate after surgical excision and radiotherapy by improving the oxygen level of the tissue and alleviating the inflammatory process. 展开更多
关键词 KELOID Hyperbaric oxygen therapy Surgical excision RADIOTHERAPY Recurrence rate
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Comparison of combined phacotrabeculectomy with trabeculectomy only in the treatment of primary angle-closure glaucoma 被引量:15
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作者 WANG Mei FANG Min +7 位作者 BAI Yu-jing ZHANG wei-zhong LIN Ming-kai LIU Bing-qian HAO Yuan-tao LING Yun-lan ZHUO Ye-hong GE Jian 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第8期1429-1433,共5页
Background Trabeculectomy has become a mainstream treatment in intraocular pressure (lOP) reduction for primary angle-closure glaucoma (PACG); combined trabeculectomy and cataract surgery was reported to reduce lO... Background Trabeculectomy has become a mainstream treatment in intraocular pressure (lOP) reduction for primary angle-closure glaucoma (PACG); combined trabeculectomy and cataract surgery was reported to reduce lOP and simultaneously improve vision for patients with PACG and coexisting cataract. This study was specialized to compare the efficacy and safety of combined phacotrabeculectomy with that of trabeculectomy only in the treatment of PACG with coexisting cataract. Methods This is a comparative case series study. Thirty-one patients (31 eyes) with PACG and coexisting cataract were enrolled. Of these, 17 underwent phacotrabeculectomy and 14 underwent trabeculectomy alone, lOP, filtering blebs, and complications were compared at the final follow-up. Complete success was defined as a final lOP less than 21 mmHg without lOP-lowering medication. Results After 10 months of postoperative follow-up, the phacotrabeculectomy and trabeculectomy groups showed no significant differences regarding lOP reduction ((20.59±7.94) vs. (24.85±14.39) mmHg, P=0.614), complete success rate (88% vs. 71%, P=0.370), formation rate of functioning blebs (65% (11/17) vs. 93% (13/14), P=0.094), and complications (41% (7/17) vs. 57% (8/14), P=0.380). lOP-lowering medication was not required for most of the patients in both groups. Additional surgery interventions, including anterior chamber reformation and phacoemulsification, were needed in the trabeculectomy group, whereas no surgery was needed postoperatively in the phacotrabeculectomy group. Conclusion Phacotrabeculectomy and trabeculectomy treatments exhibit similar lOP reduction, successful rates, and complications when it comes to treating PACG patients with coexisting cataract, although additional surgery intervention may be needed for a few cases with cataract and complications after trabeculectomy. 展开更多
关键词 primary angle-closure glaucoma TRABECULECTOMY PHACOTRABECULECTOMY CATARACT
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Effect of p27^(KIP1) on cell cycle and apoptosis in gastric cancer cells 被引量:10
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作者 Jian-Yong Zheng wei-zhong Wang +2 位作者 Kai-Zong Li Wen-Xian Guan wei Yan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第45期7072-7077,共6页
AIM: To elucidate the effect of p27^KIP1 on cell cycle and apoptosis regulation in gastric carcinoma cells. METHODS: The whole length of p27^KIP1 cDNA was transfected into human gastric cancer cell line SCG7901 by l... AIM: To elucidate the effect of p27^KIP1 on cell cycle and apoptosis regulation in gastric carcinoma cells. METHODS: The whole length of p27^KIP1 cDNA was transfected into human gastric cancer cell line SCG7901 by lipofectamine. Expression of p27^KIP1 protein or mRNA was analyzed by Western blot and RNA dot blotting, respectively. Effect of p27^KIP1 on cell growth was observed by MTT assay and anchorage-independent growth in soft agar. Tumorigenicity in nude mice was used to assess the in vivo biological effect of p27^KIP1. Flow cytometry, TUNEL, and electron microscopy were used to assess the effect of p27^KIP1 on cell cycle and apoptosis. RESULTS: Expression of p27^KIP1 protein or mRNA increased evidently in SCG7901 cells transfected with p27^KIP1. The cell growth was reduced by 31% at 48 h after induction with zinc determined by cell viability assay. The alteration of cell malignant phenotype was evidently indicated by the loss of anchorage-independent growth ability in soft agar. The tumorigenicity in nude mice was reduced evidently (0.55±0.14 cm vs 1.36±0.13cm, P〈0.01). p27^KIP1 overexpression caused cell arrest with 36% increase (from 33.7% to 69.3%, P〈0.01) in G1 population. Prolonged p27^KIP1 expression induced apoptotic cell death reflected by pre-G1 peak in the histogram of FACS, which was also confirmed by TUNEL assay and electron microscopy. CONCLUSION: p27^KIP1 can prolong cell cycle in G1 phase and lead to apoptosis, p27^KIP1 may be a good candidate for cancer gene therapy. 展开更多
关键词 Cell cycle APOPTOSIS Gastric neoplasm P27^KIP1
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Early definitive surgery in the management of severe acute pancreatitis 被引量:14
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作者 wei-zhong Zhang the Department of Surgery, Taizhou First People’s Hospital, Taizhou 318020, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2003年第4期496-499,共4页
OBJECTIVE: To assess the role of early peritoneal lavage and drainage in the management of severe acute pancreatitis. DATA SOURCES: Early peritoneal lavage and drainage was defined as that lavage and drainage should b... OBJECTIVE: To assess the role of early peritoneal lavage and drainage in the management of severe acute pancreatitis. DATA SOURCES: Early peritoneal lavage and drainage was defined as that lavage and drainage should be done in the peritoneal cavity without interference of the pancreas within 72 hours after onset of acute pancreatitis. Biomedical literature database (Medline) from 1981 through 2003 was retrieved and papers about this treatment were analyzed. RESULTS: Nine papers retrieved included 179 patients with severe acute pancreatitis. In 108 patients undergoing closed peritoneal lavage and drainage, 7 died, in 15 patients having laparoscopic procedure, 1 died, and in 56 patients having open procedure 2 died. The total survival rate was 94.4%. CONCLUSIONS: Even if extensive pancreatic necrosis occurs, early peritoneal lavage and drainage is feasible to keep the inflammatory pancreas intact and drain peri-pancreatic region in an attempt to improve the survival rate. 展开更多
关键词 PANCREATITIS NECROTIZING SURGERY
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Transarterial embolization for massive gastrointestinal hemorrhage following abdominal surgery 被引量:11
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作者 Chun-Gao Zhou Hai-Bin Shi +5 位作者 Sheng Liu Zheng-Qiang Yang Lin-Bo Zhao Jin-Guo Xia wei-zhong Zhou Lin-Sun Li 《World Journal of Gastroenterology》 SCIE CAS 2013年第40期6869-6875,共7页
AIM:To evaluate the clinical results of angiography and embolization for massive gastrointestinal hemorrhage after abdominal surgery.METHODS:This retrospective study included 26 patients with postoperative hemorrhage ... AIM:To evaluate the clinical results of angiography and embolization for massive gastrointestinal hemorrhage after abdominal surgery.METHODS:This retrospective study included 26 patients with postoperative hemorrhage after abdominal surgery. All patients underwent emergency transarterial angiography,and 21 patients underwent emergency embolization. We retrospectively analyzed the angiographic features and the clinical outcomes of transcatheter arterial embolization.RESULTS:Angiography showed that a discrete bleeding focus was detected in 21(81%) of 26 patients.Positive angiographic findings included extravasations of contrast medium(n = 9),pseudoaneurysms(n =9),and fusiform aneurysms(n = 3). Transarterial embolization was technically successful in 21(95%) of 22patients. Clinical success was achieved in 18(82%) of 22 patients. No postembolization complications were observed. Three patients died of rebleeding.CONCLUSION:The positive rate of angiographic findings in 26 patients with postoperative gastrointestinal hemorrhage was 81%. Transcatheter arterial embolization seems to be an effective and safe method in the management of postoperative gastrointestinal hemorrhage. 展开更多
关键词 TRANSCATHETER ARTERIAL EMBOLIZATION POSTOPERATIVE HEMORRHAGE COMPLICATIONS Surgery
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Microbial Degradation of Quinoline: Kinetics Study With Burkholderia picekttii 被引量:11
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作者 JIAN-LONGWANG wei-zhong XUANZHAO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第1期21-26,共6页
Objective To investigate the kinetics of quinoline biodegradation by Burkholderia pickttii, a Gram negative rod-shaped aerobe, isolated in our laboratory. Methods HPLC (Hewlett-Packard model 5050 with an UV detector) ... Objective To investigate the kinetics of quinoline biodegradation by Burkholderia pickttii, a Gram negative rod-shaped aerobe, isolated in our laboratory. Methods HPLC (Hewlett-Packard model 5050 with an UV detector) was used for the analysis of quinoline concentration. GC/MS method was used to identify the intermediate metabolites of quinoline degradation. Results The biodegradation of quinoline was inhibited by quinoline at a high concentration, and the degradation process could be described by the Haldane model. The kinetic parameters based on Haldane substrate inhibition were evaluated. The values were v = 0.44 h-1,Ks=166.7 mg/L, Ki= 650 mg/L, respectively. The quinoline concentration to avoid substrate inhibition was inferred theoretically and determined to be 329 mg/L. Conclusion The biodegradation of quinoline conforms to the Haldane inhibition model and the main intermediate metabolite of quinoline biodegradation is 2-hydroxy-quinoline. 展开更多
关键词 QUINOLINE Microbial degradation Burkholderia pickttii KINETICS Substrate inhibition Intermediate metabolite
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Feasibility of central loop TEM method for prospecting multilayer water-fi lled goaf 被引量:9
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作者 Yan Shu Xue Gou-Qiang +2 位作者 Qiu wei-zhong Li Hai zhong Hua-Sen 《Applied Geophysics》 SCIE CSCD 2016年第4期587-597,736,共12页
With deep mining of coal mines, prospecting multilayer water-filled goaf has become a new content that results from geophysical exploration in coalfields. The central loop transient electromagnetic (TEM) method is f... With deep mining of coal mines, prospecting multilayer water-filled goaf has become a new content that results from geophysical exploration in coalfields. The central loop transient electromagnetic (TEM) method is favorable for prospecting conductive layers because of the coupling relationship between its field structure and formation. However, the shielding effect of conductive overburden would not only require a longer observation time when prospecting the same depth but also weaken the anomalous response of underlying layers. Through direct time domain numerical simulation and horizontal layered earth forward modeling, this paper estimates the length of observation time required to prospect the target, and the distinguishable criterion of multilayer water-filled goal is presented with observation error according to the effect of noise on observation data. The observed emf curves from Dazigou Coal Mine, Shanxi Province can distinguish multilayer water-filled goaf. In quantitative inversion interpretation of observed curves, using electric logging data as initial parameters restrains the equivalence caused by coal formation thin layers. The deduced three-layer and two-layer water-filled goals are confirmed by the drilling hole. The result suggests that when observation time is long enough and with the anomalous situation of underlying layers being greater than the observation error, the use of the central loop TEM method to orosoect a multilaver water-filled goaf is feasible. 展开更多
关键词 central loop TEM method prospecting multilayer water-filled goaf conductive shielding layer numerical and theoretical analysis length of observation time observation error distinguishable criterion
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Angiotensin-Converting Enzyme 2 in the Rostral Ventrolateral Medulla Regulates Cholinergic Signaling and Cardiovascular and Sympathetic Responses in Hypertensive Rats 被引量:9
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作者 Yu Deng Xing Tan +2 位作者 Miao-Ling Li wei-zhong Wang Yang-Kai Wang 《Neuroscience Bulletin》 SCIE CAS CSCD 2019年第1期67-78,共12页
The rostral ventrolateral medulla(RVLM) is a key region in cardiovascular regulation. It has been demonstrated that cholinergic synaptic transmission in the RVLM is enhanced in hypertensive rats. Angiotensinconverting... The rostral ventrolateral medulla(RVLM) is a key region in cardiovascular regulation. It has been demonstrated that cholinergic synaptic transmission in the RVLM is enhanced in hypertensive rats. Angiotensinconverting enzyme 2(ACE2) in the brain plays beneficial roles in cardiovascular function in hypertension. The purpose of this study was to determine the effect of ACE2 overexpression in the RVLM on cholinergic synaptic transmission in spontaneously hypertensive rats(SHRs).Four weeks after injecting lentiviral particles containing enhanced green fluorescent protein and ACE2 bilaterally into the RVLM, the blood pressure and heart rate were notably decreased. ACE2 overexpression significantly reduced the concentration of acetylcholine in microdialysis fluid from the RVLM and blunted the decrease in blood pressure evoked by bilateral injection of atropine into the RVLM in SHRs. In conclusion, we suggest that ACE2 overexpression in the RVLM attenuates the enhanced cholinergic synaptic transmission in SHRs. 展开更多
关键词 Hypertension RENIN-ANGIOTENSIN system Gene transfer ACETYLCHOLINE SYMPATHETIC NERVE activity
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Flotation performances of polymorphic pyrrhotite 被引量:9
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作者 HE Ming-fei QIN Wen qing +1 位作者 LI wei-zhong JIAO Fen 《Journal of Central South University》 SCIE EI CAS 2012年第1期238-243,共6页
The floatability of different crystalline structures of pyrrhotite(monoclinic and hexagonal) was studied.It is shown that the floatability of monoclinic and hexagonal has obvious difference,and that the flotation reco... The floatability of different crystalline structures of pyrrhotite(monoclinic and hexagonal) was studied.It is shown that the floatability of monoclinic and hexagonal has obvious difference,and that the flotation recovery of monoclinic pyrrhotite is larger than that of hexagonal pyrrhotite using different collectors.When butyl dithiophosphate is used as the collector,the recovery is larger than that by sodium butyl xanthate and sodium diethyl dithiocarbamate.At the pH values ranging from 6 to 9,monoclinic pyrrhotite can be floated well,and the flotation recovery is higher than 90%.Monoclinic and hexagonal pyrrhotites are more easily activated by Cu2+ in acidic conditions than in alkaline conditions.But Cu2+ cannot activate hexagonal pyrrhotite using sodium diethyldithiocarbamate as the collector.By the measurement of contact angle,it is indicated that monoclinic and hexagonal pyrrhotites float well and are easily activated by Cu2+ when dithiophosphate is used as the collector.Using sodium diethyl dithiocarbamate as a collector,the relationship between potential and pH range for pyrrhotite flotation is established.At pH 5,the optimal potential range for flotation of monoclinic pyrrhotite is about 125-580 mV(vs SHE),with the maximum flotation occurring at about 350 mV(vs SHE);the optimal potential range for flotation of hexagonal pyrrhotite is 200?580 mV(vs SHE),with the maximum flotation occurring at about 300 mV(vs SHE). 展开更多
关键词 FLOTATION PYRRHOTITE pulp potential contact angle
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Phase transformation and reduction kinetics during the hydrogen reduction of ilmenite concentrate 被引量:8
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作者 Xin-guo Si Xiong-gang Lu +2 位作者 Chuan-wei Li Chong-he Li wei-zhong Ding 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第5期384-390,共7页
The reduction of ilmenite concentrate by hydrogen gas was investigated in the temperature range of 500 to 1200℃. The microstructure and phase transition of the reduction products were studied by X-ray diffraction (... The reduction of ilmenite concentrate by hydrogen gas was investigated in the temperature range of 500 to 1200℃. The microstructure and phase transition of the reduction products were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and optical microscopy (OM). It was found that the weight loss and iron metallization rate increased with the increase of reduction temperature and reaction time. The iron metallization rate could reach 87.5% when the sample was reduced at 1150℃ for 80 min. The final phase constituents mainly consist of Fe, M305 solid solution phase (M=Mg, Ti, and Fe), and few titanium oxide. Microstructure analysis shows that the surfaces of the reduction products have many holes and cracks and the reactions take place from the exterior of the grain to its interior. The kinetics of reduction indicates that the rate-controlling step is diffusion process control with the activation energy of 89 kJ.mo1-1. 展开更多
关键词 ILMENITE phase transformations KINETICS HYDROGEN reduction METALLIZATION
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GATIS score for predicting the prognosis of rectal neuroendocrine neoplasms:A Chinese multicenter study of 12-year experience 被引量:3
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作者 Xin-Yu Zeng Ming zhong +13 位作者 Guo-Le Lin Cheng-Guo Li wei-zhong Jiang wei Zhang Li-Jian Xia Mao-Jun Di Hong-Xue Wu Xiao-Feng Liao Yue-Ming Sun Min-Hao Yu Kai-Xiong Tao Yong Li Rui Zhang Peng Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第28期3403-3417,共15页
BACKGROUND There is currently a shortage of accurate,efficient,and precise predictive instruments for rectal neuroendocrine neoplasms(NENs).AIM To develop a predictive model for individuals with rectal NENs(R-NENs)usi... BACKGROUND There is currently a shortage of accurate,efficient,and precise predictive instruments for rectal neuroendocrine neoplasms(NENs).AIM To develop a predictive model for individuals with rectal NENs(R-NENs)using data from a large cohort.METHODS Data from patients with primary R-NENs were retrospectively collected from 17 large-scale referral medical centers in China.Random forest and Cox proportional hazard models were used to identify the risk factors for overall survival and progression-free survival,and two nomograms were constructed.RESULTS A total of 1408 patients with R-NENs were included.Tumor grade,T stage,tumor size,age,and a prognostic nutritional index were important risk factors for prognosis.The GATIS score was calculated based on these five indicators.For overall survival prediction,the respective C-indexes in the training set were 0.915(95%confidence interval:0.866-0.964)for overall survival prediction and 0.908(95%confidence interval:0.872-0.944)for progression-free survival prediction.According to decision curve analysis,net benefit of the GATIS score was higher than that of a single factor.The time-dependent area under the receiver operating characteristic curve showed that the predictive power of the GATIS score was higher than that of the TNM stage and pathological grade at all time periods.CONCLUSION The GATIS score had a good predictive effect on the prognosis of patients with R-NENs,with efficacy superior to that of the World Health Organization grade and TNM stage. 展开更多
关键词 Rectal neuroendocrine neoplasm NOMOGRAM Random forest PROGNOSIS Overall survival Progression-free survival
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Genetic instability of BRCA1 gene at locus D17S855 is related to clinicopathological behaviors of gastric cancer from Chinese population 被引量:6
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作者 Xue-Rong Chen wei-zhong Zhang +1 位作者 Xing-Qiu Lin Jin-wei Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第26期4246-4249,共4页
AIM: To investigate genetic instability of gene BRCA1 at locus D17S855, and their relationship with clinicopathological characteristics of gastric cancer in Chinese population. METHODS: Microsatellite instability (... AIM: To investigate genetic instability of gene BRCA1 at locus D17S855, and their relationship with clinicopathological characteristics of gastric cancer in Chinese population. METHODS: Microsatellite instability (MSI) and loss of heterozygosity (LOH) of gene BRCA1 at locus D17S855 were compared between 37 samples of gastric cancer and corresponding non-cancerous gastric tissue. RESULTS: MSI at locus D17S855 was positive in 7 of 37 samples of gastric cancer (18.95%). MSI had a close relationship with TNM staging but no relation with lymph node metastasis, histological type or tumor differentiation. MSI positive frequency in TNM Ⅰ + Ⅱ (31.58%, 6/19) was much higher than that in TNM Ⅲ+ Ⅳ (5.56%, 1/18), (P 〈 0.05). LOH positive rate was 18.92% (7/37). LOH had no relationship to histological type, tumor differentiation or lymph node metastasis, but LOH positive rate in TNM Ⅲ+ Ⅳ was 33.33% (6/18), much higher than that in TNM Ⅰ + Ⅱ ( 5.26%, 1/19), (P 〈 0.05). BRCA1 protein was expressed in 14 of 37 samples of gastric cancer. The positive rates of BRCA1 protein in TNM Ⅰ + Ⅱ and TNM Ⅲ+ Ⅳ were 57.89% and 16.67%, respectively, (P 〈 0.05). The positive rate of BRCA1 protein was 77.78% in high differentiation samples, 30.77% in middle differentiation and 12.50% in lower differentiation samples, (P 〈 0.05). CONCLUSION: MSI of BRCA1 gene could be used as a molecular marker in early phases of sporadic gastric cancer in Chinese population. LOH occurs at later period of gastric cancer, therefore, it could be used as prognostic factor. 展开更多
关键词 Gastric cancer BRCA1 gene Microsatellite instability Loss of heterozygosity
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ANGPTL2 expression in gastric cancer tissues and cells and its biological behavior 被引量:7
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作者 wei-zhong Sheng Yu-Sheng Chen +3 位作者 Chuan-Tao Tu Juan He Bo Zhang wei-Dong Gao 《World Journal of Gastroenterology》 SCIE CAS 2016年第47期10364-10370,共7页
AIM To explore expression of angiopoietin-like protein 2(ANGpT L2) and its effect on biological behavior such as proliferation and invasiveness in gastric cancer. METHODS Western blotting was used to detect expression... AIM To explore expression of angiopoietin-like protein 2(ANGpT L2) and its effect on biological behavior such as proliferation and invasiveness in gastric cancer. METHODS Western blotting was used to detect expression of ANGp TL2 in 60 human normal gastric tissues, 60 human gastric cancer tissues and gastric cell lines including GES-1, N87, SGC7901, BGC823 and pA MC82. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) and Transwell assay were used to detect the proliferation and invasive ability of gastric cancer cells. RESULTS Compared to normal tissues, ANGp TL2 protein levels were significantly upregulated in gastric tissues, and this level was closely correlated with gastric tumor grade, clinical stage and lymph node metastasis. Compared to GES-1 cells, ANGpT L2 mR NA and protein levels were significantly increased in gastric cancer cells including N87, SGC7901, BGC823 and p AMC82. The expression of ANGpT L2 in highly malignant gastric cancer cell lines BGC823 and pA MC82 was significantly higher than in low malignancy gastric cancer cell lines N87 and SGC7901. MTT and Transwell experiments indicated that the proliferation rate and invasive ability of stable overexpressed gastric cancer cells was faster than in cells transfected with Lv-NC and blank controlcells, and the invasive ability of stable overexpressed gastric cancer cells was higher than that of cells transfected with Lv-NC and blank control cells.CONCLUSION ANGp TL2 contributed to proliferation and invasion of gastric cancer cells. In clinical treatment, ANGpT L2 may become a new target for treatment of gastric cancer. 展开更多
关键词 Gastric cancer Angiopoietin-like protein 2 Cell invasion Cell proliferation
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Expression of NF-kappaB in rotavirus-induced damage to the liver and biliary tract in neonatal mice 被引量:7
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作者 Huang, Lei Gu, wei-zhong +2 位作者 Si, Xin-Min wei, Ming-Fa Feng, Jie-Xiong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第2期188-193,共6页
BACKGROUND: Biliary atresia, the etiology of which still remains unclear, occurs exclusively in newborns and most are infected with rotavirus. In this study, we aimed to investigate the histopathological patterns of d... BACKGROUND: Biliary atresia, the etiology of which still remains unclear, occurs exclusively in newborns and most are infected with rotavirus. In this study, we aimed to investigate the histopathological patterns of different kinds of rotavirus in the liver and biliary tract of neonatal mice and the expression of NF-kappa B in the liver and biliary tract of infected mice. METHODS: Twenty-three adult mice (8 were male and 15 female) were divided into 8 breeding pairs, and each pair (I male and 2 females) was housed in a cage in a laminar flow hood. Newborn mice, 24-48 hours old were randomly divided into A, B and C groups. The A and B groups were respectively inoculated with MMU18006 and SA11 rotavirus through the intraperitoneal route, while group C as blank control was only inoculated with culture medium. The liver was dissected after 5, 10, 15, 21 and 28 days; the weight of each mouse and the histopathological patterns in the liver were recorded. The expression of NF-kappa B in the liver and intrahepatic bile ducts was detected by immunohistochemical staining and the expression intensity was analyzed with a GT-2 imaging instrument. RESULTS: The average increase in weight of infected mice was significantly slower than that of the normal control, while the growth rate of group A (injected with MMU18006 rotavirus) was slower than that of group B (SA11 rotavirus). In infected mice, the acute and chronic inflammation of liver and intra- and extra-hepatic bile ducts was more significant in group A. Stenosis was found in most intrahepatic bile ducts, and sporadically in extrahepatic bile ducts. The expression of NF-kappa B in infected mice was dramatically higher than that of the normal control, while the expression in group A was higher than in group B. CONCLUSIONS: Significant damage to the liver and biliary tract of neonatal mice can be induced by inoculating MMU18006 rotavirus through the intraperitoneal route, which is very similar to the pathology of biliary atresia in the newborn human. Similar inoculation with 展开更多
关键词 ROTAVIRUS biliary atresia NF-kappa B
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Interleukin-17 plays a critical role in the acute rejection of intestinal transplantation 被引量:7
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作者 Jian-Jun Yang Fan Feng +8 位作者 Liu Hong Li Sun Meng-Bin Li Ran Zhuang Feng Pan Ying-Mei Wang wei-zhong Wang Guo-Sheng Wu Hong-wei Zhang 《World Journal of Gastroenterology》 SCIE CAS 2013年第5期682-691,共10页
AIM:To investigate the role of interleukin(IL)-17 in small bowel allograft rejection.METHODS:We detected the expression of helper T cell 17(Th17)cells in biopsy specimens from 3 cases of living small bowel transplanta... AIM:To investigate the role of interleukin(IL)-17 in small bowel allograft rejection.METHODS:We detected the expression of helper T cell 17(Th17)cells in biopsy specimens from 3 cases of living small bowel transplantation in our department through immunofluorescence stain.We then established a rat heterotopic small bowel transplantation model.The rats were sacrificed on the 1st,2nd,3rd,5th, and 7th d after small bowel transplantation.The degrees of transplantation rejection in rat intestine graft were examined through hematoxylin eosin(HE)stain, and the expression of Th17 cells in rat intestine graft were detected through immunofluorescence stain. In addition,the recipient rats undergoing intestinal transplantation were administrated with mouse-anti-rat IL-17 monoclonal antibody(mAb),and the survival of rats was analyzed.The recipient rats which received mouse-anti-rat IL-17 mAb treatment were sacrificed on the 1st,2nd,3rd,5th,and 7th d after small bowel transplantation.The degrees of transplantation rejection and the expression of Th17 cells in rat intestine graft were detected through HE and immunofluorescence stain. The expression of IL-17,IL-1β,tumor necroses factor receptor-α(TNF-α),IL-6,and IL-8 in the intestine graft or serum were also detected. RESULTS:The expressions of Th17 cells ran parallel with the degree of acute rejection in human intestine grafts.The intestine graft rejection of rats was aggravated with prolonged duration after intestinal transplantation,and the expressions of Th17 cells were also correlated with the degree of acute rejection in rat intestine grafts.Administration of mouse-anti-rat IL-17 mAb prolonged the survival of rats after small bowel transplantation(P<0.001).Furthermore,we found that the administration of mouse-anti-rat IL-17 mAb significantly decreased the intensity of CD4+IL-17+Th17 cells in intestine grafts on the 2nd,3rd,5th,and the 7th d (97.22±4.05vs 12.45±2.02 on the 7th d,P<0.0001), and suppressed the severity of acute rejection.The expression of IL-17 in the in 展开更多
关键词 INTERLEUKIN-17 HELPER T cell 17 Small BOWEL transplantation Acute REJECTION MONOCLONAL antibody
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