The three-dimensional unsteady turbulent flow in axial-flow pumps was simulated based on Navier-Stoke solver embedded with k - ε RNG turbulence model and SIMPLEC algorithm. Numerical results show that the unsteady pr...The three-dimensional unsteady turbulent flow in axial-flow pumps was simulated based on Navier-Stoke solver embedded with k - ε RNG turbulence model and SIMPLEC algorithm. Numerical results show that the unsteady prediction results are more accurate than the steady results, and the maximal error of unsteady prediction is only 4.54%. The time-domain spectrums show that the static pressure fluctuation curves at the inlet and outlet of the rotor and the outlet of the stator are periodic, and all have four peaks and four valleys. The pressure fluctuation amplitude increases from the hub to the tip at the inlet and outlet of the rotor, but decreases at the outlet of the stator. The pressure fluctuation amplitude is the greatest at the inlet of the rotor, and the average amplitude decreases sharply from the inlet to the outlet. The frequency spectrums obtained by Fast Fourier Transform （FFT） show that the dominant frequency is approximately equal to the blade passing frequency. The static pressure on the pressure side of hydrofoil on different stream surfaces remains almost consistent, and increases gradually from the blade inlet to the exit on the suction side at different time steps. The axial velocity distribution is periodic and is affected by the stator blade number at the rotor exit. The experimental results show that the flow is almost axial and the pre-rotation is very small at the rotor inlet under the conditions of 0.8 QN -1.2 QN Due to the clearance leakage, the pressure, circulation and meridional velocity at the rotor outlet all decrease near the hub leakage and tip clearance regions.展开更多
踝关节骨折是创伤骨科常见骨折之一。通过引入加速康复外科(enhanced recovery after surgery,ERAS)理念,对围手术期处理措施进行全面优化,可以进一步提高患者诊疗效果。为规范ERAS临床路径在踝关节骨折中的应用,基于前期研究经验,以循...踝关节骨折是创伤骨科常见骨折之一。通过引入加速康复外科(enhanced recovery after surgery,ERAS)理念,对围手术期处理措施进行全面优化,可以进一步提高患者诊疗效果。为规范ERAS临床路径在踝关节骨折中的应用,基于前期研究经验,以循证医学证据为依据,经过全国专家组反复讨论,编制该专家共识,供全国创伤骨科医师在临床工作中参考。该共识适用于所有进行择期手术治疗的成人新鲜踝关节骨折患者。共识共包含25条推荐意见,就踝关节骨折患者急诊处理、术前准备、术中处理以及术后恢复进行了全面介绍。展开更多
There is considerable potential for integrating transarterial chemoembolization(TACE),programmed death-(ligand)1(PD-[L]1)inhibitors,and molecular targeted treatments(MTT)in hepatocellular carcinoma(HCC).It is necessar...There is considerable potential for integrating transarterial chemoembolization(TACE),programmed death-(ligand)1(PD-[L]1)inhibitors,and molecular targeted treatments(MTT)in hepatocellular carcinoma(HCC).It is necessary to investigate the therapeutic efficacy and safety of TACE combined with PD-(L)1 inhibitors and MTT in real-world situations.In this nationwide,retrospective,cohort study,826 HCC patients receiving either TACE plus PD-(L)1 blockades and MTT(combination group,n=376)or TACE monotherapy(monotherapy group,n=450)were included from January 2018 to May 2021.The primary endpoint was progression-free survival(PFS)according to modified RECIST.The secondary outcomes included overall survival(OS),objective response rate(ORR),and safety.We performed propensity score matching approaches to reduce bias between two groups.After matching,228 pairs were included with a predominantly advanced disease population.Median PFS in combination group was 9.5 months(95%confidence interval[CI],8.4-11.0)versus 8.0 months(95%CI,6.6-9.5)(adjusted hazard ratio[HR],0.70,P=0.002).OS and ORR were also significantly higher in combination group(median OS,19.2[16.1-27.3]vs.15.7 months[13.0-20.2];adjusted HR,0.63,P=0.001;ORR,60.1%vs.32.0%;P<0.001).Grade 3/4 adverse events were observed at a rate of 15.8%and 7.5%in combination and monotherapy groups,respectively.Our results suggest that TACE plus PD-(L)1 blockades and MTT could significantly improve PFS,OS,and ORR versus TACE monotherapy for Chinese patients with predominantly advanced HCC in real-world practice,with an acceptable safety profile.展开更多
Alzheimer’s disease(AD), the most common type of dementia, is becoming a major challenge for global health and social care. However, the current understanding of AD pathogenesis is limited, and no early diagnosis and...Alzheimer’s disease(AD), the most common type of dementia, is becoming a major challenge for global health and social care. However, the current understanding of AD pathogenesis is limited, and no early diagnosis and disease-modifying therapy are currently available. During the past year, significant progress has been made in clinical research on the diagnosis, prevention, and treatment of AD.In this review, we summarize the latest achievements,including diagnostic biomarkers, polygenic hazard score,amyloid and tau PET imaging, clinical trials targeting amyloid-beta(Ab), tau, and neurotransmitters, early intervention, and primary prevention and systemic intervention approaches, and provide novel perspectives for further efforts to understand and cure the disease.展开更多
Integral imaging is a promising three-dimensional(3D)imaging technique that captures and reconstructs light field information.Microlens arrays are usually used for the reconstruction process to display 3D scenes to th...Integral imaging is a promising three-dimensional(3D)imaging technique that captures and reconstructs light field information.Microlens arrays are usually used for the reconstruction process to display 3D scenes to the viewer.However,the inherent chromatic aberration of the microlens array reduces the viewing quality,and thus,broadband achromatic imaging remains a challenge for integral imaging.Here,we realize a silicon nitride metalens array in the visible region that can be used to reconstruct 3D optical scenes in the achromatic integral imaging for white light.The metalens array contains 60×60 polarization-insensitive metalenses with nearly diffraction-limited focusing.The nanoposts in each high-efficiency(measured as 47%on average)metalens are delicately designed with zero effective material dispersion and an effective achromatic refractive index distribution from 430 to 780 nm.In addition,such an achromatic metalens array is composed of only a single silicon nitride layer with an ultrathin thickness of 400 nm,making the array suitable for on-chip hybrid-CMOS integration and the parallel manipulation of optoelectronic information.We expect these findings to provide possibilities for full-color and aberration-free integral imaging,and we envision that the proposed approach may be potentially applicable in the fields of high-power microlithography,high-precision wavefront sensors,virtual/augmented reality and 3D imaging.展开更多
AIM: To investigate the effect of H pylori eradication on atrophic gastritis and intestinal metaplasia (IM).METHODS: Two hundred and fifty-nine patients with atrophic gastritis in the antrum were included in the study...AIM: To investigate the effect of H pylori eradication on atrophic gastritis and intestinal metaplasia (IM).METHODS: Two hundred and fifty-nine patients with atrophic gastritis in the antrum were included in the study, 154 patients were selected for H pylori eradication therapy and the remaining 105 patients served as untreated group. Gastroscopy and biopsies were performed both at the beginning and at the end of a 3-year follow-up study. Gastritis was graded according to the updated Sydney system.RESULTS: One hundred and seventy-nine patients completed the follow-up, 92 of them received H pylori eradication therapy and the remaining 87 H pyloriinfected patients were in the untreated group. Chronic gastritis, active gastritis and the grade of atrophy significantly decreased in H pylori eradication group (P＜0.01). However, the grade of IM increased in H pylori -infected group (P＜0.05).CONCLUSION: H pylori eradication may improve gastric mucosal inflammation, atrophy and prevent the progression of IM.展开更多
Background Generally, total surgical removal of craniopharyngioma results in satisfactory outcome with a low recurrence rate, however, the location of the tumor and its adherence to the hypothalamic structures can mak...Background Generally, total surgical removal of craniopharyngioma results in satisfactory outcome with a low recurrence rate, however, the location of the tumor and its adherence to the hypothalamic structures can make the operation difficult. The goal of the present study was to assess the outcome of craniopharyngiomas in 284 patients treated surgically. Methods A total of 284 patients （151 men and 133 women） with craniopharyngioma were treated surgically by our neurosurgeons from January 1996 to March 2006. Among them, 226 （79.6%） patients were adults （15 years of age or older; mean, 35.8 ± 10.6）, 58 （20.4%） were children （14 years of age or younger; mean, 9.1 ± 3.8）. The diameter of the tumors were 2.0-9.0 cm （mean, 36.54± 11.4）. The tumors were classified into the superior （23 patients） and inferior ventricular （261） types according to the location of the tumor relative to the third ventricular floor. For the patients with craniopharyngioma of inferior ventricular type, pterional approach was used in 191 （67.3%） patients, subfrontal approach in 17 （6.0%）, and translamina terminalis through frontobasal interhemispheric approach in 53 08.7%）. For those with the tumors of superior ventricular type, transcallosal approach into the anterior third ventricle was done in 10 （3.5%） patients, and the lamina terminalis approach in 13 （4.6%）. Of the 284 patients, 204 （71.8%） were followed up for 0.5 to 8 years （mean, 2.1 ± 1.8）, including 162 patients received total tumor removal, and 37 underwent subtotal or partial removal. Results Total, subtotal and partial removal of the tumors were achieved in 237 （83.5%）, 34 （12.0%） and 13 （4.5%） patients, respectively. The pituitary stalk was preserved in 176 （62.0%） patients, severed in 52 （18.3%）, and unidentified in 56 （19.7%）. Twelve （4.2%） patients died within one month after the surgery. During the follow-up, 23 （14.1%） patients experienced tumor recurrence 1.0-3.5 years （mean, 1展开更多
基金Project supported by the National High Technology Research and Development Program of China (863 Program,Grant No.2007AA05Z207)the Graduate Student Innovation Foundation of Jiangsu Province (Grant No.CX08B_064Z)the National Science and Technology Support Program (Grant No.2008BAF34B15)
文摘The three-dimensional unsteady turbulent flow in axial-flow pumps was simulated based on Navier-Stoke solver embedded with k - ε RNG turbulence model and SIMPLEC algorithm. Numerical results show that the unsteady prediction results are more accurate than the steady results, and the maximal error of unsteady prediction is only 4.54%. The time-domain spectrums show that the static pressure fluctuation curves at the inlet and outlet of the rotor and the outlet of the stator are periodic, and all have four peaks and four valleys. The pressure fluctuation amplitude increases from the hub to the tip at the inlet and outlet of the rotor, but decreases at the outlet of the stator. The pressure fluctuation amplitude is the greatest at the inlet of the rotor, and the average amplitude decreases sharply from the inlet to the outlet. The frequency spectrums obtained by Fast Fourier Transform （FFT） show that the dominant frequency is approximately equal to the blade passing frequency. The static pressure on the pressure side of hydrofoil on different stream surfaces remains almost consistent, and increases gradually from the blade inlet to the exit on the suction side at different time steps. The axial velocity distribution is periodic and is affected by the stator blade number at the rotor exit. The experimental results show that the flow is almost axial and the pre-rotation is very small at the rotor inlet under the conditions of 0.8 QN -1.2 QN Due to the clearance leakage, the pressure, circulation and meridional velocity at the rotor outlet all decrease near the hub leakage and tip clearance regions.
文摘踝关节骨折是创伤骨科常见骨折之一。通过引入加速康复外科(enhanced recovery after surgery,ERAS)理念,对围手术期处理措施进行全面优化,可以进一步提高患者诊疗效果。为规范ERAS临床路径在踝关节骨折中的应用,基于前期研究经验,以循证医学证据为依据,经过全国专家组反复讨论,编制该专家共识,供全国创伤骨科医师在临床工作中参考。该共识适用于所有进行择期手术治疗的成人新鲜踝关节骨折患者。共识共包含25条推荐意见,就踝关节骨折患者急诊处理、术前准备、术中处理以及术后恢复进行了全面介绍。
基金The study was supported by National Key Research and Development Program(2018YFA0704100,2018YFA0704104)National Natural Science Foundation of China(81827805,82130060)Jiangsu Provincial Special Program of Medical Science(BE2019750).The funding sources had no role in the writing of the report,or decision to submit the paper for publication.
文摘There is considerable potential for integrating transarterial chemoembolization(TACE),programmed death-(ligand)1(PD-[L]1)inhibitors,and molecular targeted treatments(MTT)in hepatocellular carcinoma(HCC).It is necessary to investigate the therapeutic efficacy and safety of TACE combined with PD-(L)1 inhibitors and MTT in real-world situations.In this nationwide,retrospective,cohort study,826 HCC patients receiving either TACE plus PD-(L)1 blockades and MTT(combination group,n=376)or TACE monotherapy(monotherapy group,n=450)were included from January 2018 to May 2021.The primary endpoint was progression-free survival(PFS)according to modified RECIST.The secondary outcomes included overall survival(OS),objective response rate(ORR),and safety.We performed propensity score matching approaches to reduce bias between two groups.After matching,228 pairs were included with a predominantly advanced disease population.Median PFS in combination group was 9.5 months(95%confidence interval[CI],8.4-11.0)versus 8.0 months(95%CI,6.6-9.5)(adjusted hazard ratio[HR],0.70,P=0.002).OS and ORR were also significantly higher in combination group(median OS,19.2[16.1-27.3]vs.15.7 months[13.0-20.2];adjusted HR,0.63,P=0.001;ORR,60.1%vs.32.0%;P<0.001).Grade 3/4 adverse events were observed at a rate of 15.8%and 7.5%in combination and monotherapy groups,respectively.Our results suggest that TACE plus PD-(L)1 blockades and MTT could significantly improve PFS,OS,and ORR versus TACE monotherapy for Chinese patients with predominantly advanced HCC in real-world practice,with an acceptable safety profile.
基金supported by the the Chinese Ministry of Science and Technology (2016YFC1306401)
文摘Alzheimer’s disease(AD), the most common type of dementia, is becoming a major challenge for global health and social care. However, the current understanding of AD pathogenesis is limited, and no early diagnosis and disease-modifying therapy are currently available. During the past year, significant progress has been made in clinical research on the diagnosis, prevention, and treatment of AD.In this review, we summarize the latest achievements,including diagnostic biomarkers, polygenic hazard score,amyloid and tau PET imaging, clinical trials targeting amyloid-beta(Ab), tau, and neurotransmitters, early intervention, and primary prevention and systemic intervention approaches, and provide novel perspectives for further efforts to understand and cure the disease.
基金supported by National Natural Science Foundation of China(11761161002,61535007,61775243,61805288)Natural Science Foundation of Guangdong Province(Grant Nos.2018B030308005,2017A030310510)Science and Technology Program of Guangzhou(201804020029).
文摘Integral imaging is a promising three-dimensional(3D)imaging technique that captures and reconstructs light field information.Microlens arrays are usually used for the reconstruction process to display 3D scenes to the viewer.However,the inherent chromatic aberration of the microlens array reduces the viewing quality,and thus,broadband achromatic imaging remains a challenge for integral imaging.Here,we realize a silicon nitride metalens array in the visible region that can be used to reconstruct 3D optical scenes in the achromatic integral imaging for white light.The metalens array contains 60×60 polarization-insensitive metalenses with nearly diffraction-limited focusing.The nanoposts in each high-efficiency(measured as 47%on average)metalens are delicately designed with zero effective material dispersion and an effective achromatic refractive index distribution from 430 to 780 nm.In addition,such an achromatic metalens array is composed of only a single silicon nitride layer with an ultrathin thickness of 400 nm,making the array suitable for on-chip hybrid-CMOS integration and the parallel manipulation of optoelectronic information.We expect these findings to provide possibilities for full-color and aberration-free integral imaging,and we envision that the proposed approach may be potentially applicable in the fields of high-power microlithography,high-precision wavefront sensors,virtual/augmented reality and 3D imaging.
基金Supported by the Scientific Research Fund of the Health Bureau of Zhejiang Province, No. 2001QN012
文摘AIM: To investigate the effect of H pylori eradication on atrophic gastritis and intestinal metaplasia (IM).METHODS: Two hundred and fifty-nine patients with atrophic gastritis in the antrum were included in the study, 154 patients were selected for H pylori eradication therapy and the remaining 105 patients served as untreated group. Gastroscopy and biopsies were performed both at the beginning and at the end of a 3-year follow-up study. Gastritis was graded according to the updated Sydney system.RESULTS: One hundred and seventy-nine patients completed the follow-up, 92 of them received H pylori eradication therapy and the remaining 87 H pyloriinfected patients were in the untreated group. Chronic gastritis, active gastritis and the grade of atrophy significantly decreased in H pylori eradication group (P＜0.01). However, the grade of IM increased in H pylori -infected group (P＜0.05).CONCLUSION: H pylori eradication may improve gastric mucosal inflammation, atrophy and prevent the progression of IM.
文摘Background Generally, total surgical removal of craniopharyngioma results in satisfactory outcome with a low recurrence rate, however, the location of the tumor and its adherence to the hypothalamic structures can make the operation difficult. The goal of the present study was to assess the outcome of craniopharyngiomas in 284 patients treated surgically. Methods A total of 284 patients （151 men and 133 women） with craniopharyngioma were treated surgically by our neurosurgeons from January 1996 to March 2006. Among them, 226 （79.6%） patients were adults （15 years of age or older; mean, 35.8 ± 10.6）, 58 （20.4%） were children （14 years of age or younger; mean, 9.1 ± 3.8）. The diameter of the tumors were 2.0-9.0 cm （mean, 36.54± 11.4）. The tumors were classified into the superior （23 patients） and inferior ventricular （261） types according to the location of the tumor relative to the third ventricular floor. For the patients with craniopharyngioma of inferior ventricular type, pterional approach was used in 191 （67.3%） patients, subfrontal approach in 17 （6.0%）, and translamina terminalis through frontobasal interhemispheric approach in 53 08.7%）. For those with the tumors of superior ventricular type, transcallosal approach into the anterior third ventricle was done in 10 （3.5%） patients, and the lamina terminalis approach in 13 （4.6%）. Of the 284 patients, 204 （71.8%） were followed up for 0.5 to 8 years （mean, 2.1 ± 1.8）, including 162 patients received total tumor removal, and 37 underwent subtotal or partial removal. Results Total, subtotal and partial removal of the tumors were achieved in 237 （83.5%）, 34 （12.0%） and 13 （4.5%） patients, respectively. The pituitary stalk was preserved in 176 （62.0%） patients, severed in 52 （18.3%）, and unidentified in 56 （19.7%）. Twelve （4.2%） patients died within one month after the surgery. During the follow-up, 23 （14.1%） patients experienced tumor recurrence 1.0-3.5 years （mean, 1
