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Two-stage analysis of pharmacokinetics of sufentanil administered by target-controlled infusion in Chinese patients 被引量:16
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作者 ZHAO Yan DUAN Jing-li +9 位作者 WU Xin-min JIANG Jian-yu LU Wei ZHANG Li-ping WANG Jun MENG Xiu-li XU Chuan-ya JIA Dong-lin LIU Wei SHENG Xiao-yan 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第17期1979-1984,共6页
Background Sufentanil is a suitable choice for target-controlled infusion (TCI) because of its shorter context-sensitive half-time. The current study was to estimate the pharmacokinetics of sufentanil TCI in Chinese... Background Sufentanil is a suitable choice for target-controlled infusion (TCI) because of its shorter context-sensitive half-time. The current study was to estimate the pharmacokinetics of sufentanil TCI in Chinese patients using the two-stage analysis. Methods Twelve adult patients with American Society of Anesthesiologists (ASA) physical status I or II undergoing elective surgery under general anesthesia were included. Anesthesia was induced with propofol, rocuronium and sufentanil administered by TCI lasting for 30 minutes, with target effect-site concentration of sufentanil 4 or 6 ng/ml. Frequent arterial blood samples (1.5 ml) were taken during and up to 24 hours after sufentanil TCI. Before the end of surgery, another arterial blood sample (1.0 ml) was drawn for the blood-gas analysis. Plasma sufentanil concentrations were determined by liquid chromatography-tandem mass spectrometry (limit of quantitation was 5 pg/ml). The data were analyzed with the two-stage approach, linear regression and correlation analysis. Results The pharmacokinetics of sufentanil TCI were adequately described by a three-compartment model. The variables were derived as follows: the volume of central compartment (V1) was 5.4 L, volume of distribution at steady-state (Vdss) was 222.6 L, metabolic clearance (CI1) was 0.84 L/min and elimination half-life (t~/2y) was 389 minutes. Patients' age, gender and PaCO2 correlated significantly with the pharmacokinetic parameters. The Vdss, volume of slowly equilibrating compartment (V3) and t1/2 y increased, and rapid distribution clearance (012) decreased with increasing patient age. Male patients had larger values of Vdss, volume of rapidly equilibrating compartment (V2) and V3 than female patients. The Vdss and V3 increased with higher PaCO2 values. There were no significant correlations between the pharmacokinetic variables and body weight, height, lean body mass, plasma albumin, sufentanil dose, duration of surgery, pH or base excess of b 展开更多
关键词 ANESTHESIA SUFENTANIL PHARMACOKINETICS target-controlled infusion two-stage analysis
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Recent advances in reservoir characterization:Introduction
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作者 Shib Sankar Ganguli A.Vasanthi Sumit Verma 《Energy Geoscience》 EI 2024年第2期180-182,共3页
Reservoir characterization refers to the process of creating a comprehensive model that characterizes the reservoir based on its ability to store and produce hydrocarbons.This includes analyzing reservoir fluid behavi... Reservoir characterization refers to the process of creating a comprehensive model that characterizes the reservoir based on its ability to store and produce hydrocarbons.This includes analyzing reservoir fluid behavior under various conditions and identifying optimal production techniques to maximize hydrocarbon recovery.For this,a holistic understanding is required that integrates data from geophysics,geostatistics,petrophysics,geology,and reservoir engineering. 展开更多
关键词 RESERVOIR GEOLOGY GEOPHYSICS
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室内装修用特制定向刨花板 被引量:3
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作者 许斌 詹先旭 +2 位作者 陈立衡 Kenneth Lau George Pan 《家具》 2014年第6期25-29,共5页
本文介绍了一种加拿大产特制定向刨花板,该板材是为室内装修和家具制造而特制的,通过对其生产原材料、生产工艺特点、产品性能的分析,并就该产品在室内装修领域进行了探讨,期望室内设计师、家具设计师和用户对该特制定向刨花板有全新的... 本文介绍了一种加拿大产特制定向刨花板,该板材是为室内装修和家具制造而特制的,通过对其生产原材料、生产工艺特点、产品性能的分析,并就该产品在室内装修领域进行了探讨,期望室内设计师、家具设计师和用户对该特制定向刨花板有全新的认识。 展开更多
关键词 特制定向刨花板 刨片 生产工艺 室内装饰 家具板材 发展趋势
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Time for the world to move beyond the percutaneous endoscopic gastrostomy 被引量:2
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作者 Ah San Pang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第23期2877-2878,共2页
Percutaneous endoscopic gastrostomy (PEG) is a proven feeding tube,just as the nasogastric tube is proven to be able to deliver enteral nutrition.For long-term use,both patient and caregiver want neither.What is desir... Percutaneous endoscopic gastrostomy (PEG) is a proven feeding tube,just as the nasogastric tube is proven to be able to deliver enteral nutrition.For long-term use,both patient and caregiver want neither.What is desired is the LOOPPEG? 3G tube,more secure than the PEG,and less risky to change than the nasogastric tube.Future clinical research should focus on this high-comfort low-risk tube. 展开更多
关键词 Tube feeding Enteral nutrition DYSPHAGIA STROKE
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APPROXIMATION PROPERTIES OF (C, α) MEANS OF DOUBLE WALSH-FOURIER SERIES
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作者 Ushangi Goginava 《Analysis in Theory and Applications》 2004年第1期77-98,共22页
We study the rate of Lp approximation by Cesaro means of the quadratic partial sums of double Walsh-Fourier series of functions from Lp.
关键词 Cesaro means double wallsh-Fourier series
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SINGULAR INTEGRALS ALONG SURFACES ON PRODUCT DOMAINS 被引量:1
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作者 Hussain Al-Qassem 《Analysis in Theory and Applications》 2004年第2期99-112,共14页
In this paper, we study the mapping properties of singular integral operator along surfaces of revolution. We prove Lp bounds (1 < p < ∞) for such singular integral operators as well as for their corresponding ... In this paper, we study the mapping properties of singular integral operator along surfaces of revolution. We prove Lp bounds (1 < p < ∞) for such singular integral operators as well as for their corresponding maximal truncated singular integrals if the singular kernels are allowed to be in certain block spaces. 展开更多
关键词 singular integrals product domains rough kernels Block spaces
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坎地沙坦对心力衰竭患者非致死性心肌梗死和心血管死亡的影响
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作者 Catherine Demers John J. V. McMurray +11 位作者 Karl Swedberg Marc A. Pfeffer Christopher B Bertil Olofsson Robert S. McKelvie Jan OEstergren Eric L. Michelson Peter A. Johansson Duolao Wang Salim Yusuf, MBBS, DPhil 孙艺红(译) 胡大一(校) 《美国医学会杂志(中文版)》 2006年第5期302-306,共5页
背景:血管紧张素转换酶(angiotensin-converting enzyme,ACE)抑制剂可降低心肌梗死(myocardial infarction,MI)的危险,但是还不清楚血管紧张素受体拮抗剂是否具有同样的效果。 目的:评价血管紧张素受体拮抗剂坎地沙坦对心力... 背景:血管紧张素转换酶(angiotensin-converting enzyme,ACE)抑制剂可降低心肌梗死(myocardial infarction,MI)的危险,但是还不清楚血管紧张素受体拮抗剂是否具有同样的效果。 目的:评价血管紧张素受体拮抗剂坎地沙坦对心力衰竭患者MI和其他冠脉事件的影响。 设计、地点和参试者:“坎地沙坦治疗心力衰竭:降低病死率和发病率评价”(Candesartan in Heart Failure:Assessment of Reduction in Mortality and Morbidity,CHARM)计划是一项随机、安慰剂对照研究。研究入选有纽约心脏病协会分级Ⅱ至Ⅳ级症状的患者(平均年龄,66[SD,11]岁)。在心力衰竭最佳治疗的基础上,随机接受坎地沙坦(目标剂量,32mg每天一次)或匹配的安慰剂。患者入选期为1999年3月至2001年3月。分组的7599例患者中,4004例(53%)有MI病史,1808例(24%)患有心绞痛。基线时,服用ACE抑制剂3125例(41%);服用β-阻滞剂4203(55%)例;降脂药物3153例(42%);阿斯匹林4246例(56%);利尿药6286例(83%)。 主要观测指标:该分析的主要终点为坎地沙坦或安慰剂组心力衰竭患者心血管死亡和非致死性MI复合发生率。 结果:在37.7个月的中位随访期间,坎地沙坦组(775例患者[20.4%])心血管死亡和非致死性MI主要终点的发生率明显低于安慰剂组(868[22.9%])(风险比[hazard ratio,HR],0.87;95%可信区间[confidence interval,CI],0.79-0.96;P=0.004;所需治疗例数[numbe rneeded to treat,NNT],40)。与安慰剂组(522[13.8%])比较,坎地沙坦组(459[12.1%])单纯非致死性MI也明显降低(HR,0.86;95%CI,0.75-0.97;P=0.02;NNT,59)。在CHARM试验预先设定的不同亚组和分析间,心血管死亡和非致死性MI危险的降低相似。坎地沙坦对不稳定心绞痛或冠脉血运重建导致的住院没有影响。结� 展开更多
关键词 心力衰竭患者 致死性心肌梗死 坎地沙坦 心血管 死亡 血管紧张素转换酶 安慰剂对照 ACE抑制剂
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Sustainability Aspects of the Wheat Sector
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作者 Istvan Kiss Szilvia Bencze 《Chinese Business Review》 2012年第5期451-459,共9页
In the frame of the present study, we examined the wheat sector with respect to economic and social sustainability. Accordingly, two research questions were formulated: (1) Is wheat production sustainable in econom... In the frame of the present study, we examined the wheat sector with respect to economic and social sustainability. Accordingly, two research questions were formulated: (1) Is wheat production sustainable in economic terms? and (2) Is wheat production sustainable in social terms? Our view is that the content of sustainability can be defined on a case-by-case basis, and in our case, wheat production provides this content. To answer the research questions, we collected statistical data on the production area, average yield, production volume, selling price, consumption of wheat, and evaluated the tendencies prevalent in the sector. We suppose that in social terms, sustainability means maintaining consumption at least at a constant level, knowing that this sector produces considerable share of the direct and indirect food raw materials. A chief dilemma is that world population is continuously growing, although the size of the cultivated area in the wheat sector has not indicated significant changes over the past few decades. Unless increasing the yields, severe decrease may occur in the per capita production of wheat in the long run. In this case, the current consumption level will not be sustainable in the medium run. In addition, in the long run, it may even have influence on the consumption level of other commodities. 展开更多
关键词 wheat sector SUSTAINABILITY COMPETITIVENESS PRODUCTION consumption level
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Unrestricted Weight Bearing as a Method for Assessment of Nociceptive Behavior in a Model of Tibiofemoral Osteoarthritis in Rats
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作者 Lise Skott Gregersen Turid Rosland +2 位作者 Lars Arendt-Nielsen Garth Whiteside Michele Hummel 《Journal of Behavioral and Brain Science》 2013年第3期306-314,共9页
Background: Novel preclinical models for prediction of osteoarthritis-like pain are necessary for the elucidation of osteoarthritis (OA) pathology and for assessment of novel analgesics. A widely used behavioral test ... Background: Novel preclinical models for prediction of osteoarthritis-like pain are necessary for the elucidation of osteoarthritis (OA) pathology and for assessment of novel analgesics. A widely used behavioral test in rat models of tibiofemoral OA is hind limb weight bearing (WB). However, this method evaluates WB in an unnaturally restricted manner. The aim of this study was therefore to characterize the Tekscan Pressure Measurement System as a means to assess OA-like tibiofemoral pain in rats by determination of plantar pressure distribution in a more natural and unrestricted position, defined as unrestricted WB. Methods: Intra-articular injections of 1 mg monosodium iodoacetate (MIA) or saline were administrated in the left hind knee of 84 male Sprague Dawley rats. Changes in unrestricted WB between ipsilateral and contralateral hindlimbs were determined. Morphine (5 mg/kg administered subcutaneously) and naproxen (60 mg/kg per-oral) were examined for their ability to reverse WB changes. Results: Changes in hind limb unrestricted WB were observed 14 (P P P Conclusion: This study indicated that unrestricted WB assessed by the Tekscan system can be utilized as a clinically relevant method to assess aberrations in WB induced by intra-articular MIA injections in rodents. Therefore, this system may be useful for understanding the mechanisms of OA pain in humans and may also assist in the discovery of novel pharmacological agents. 展开更多
关键词 OSTEOARTHRITIS PAIN Monosodium Iodoacetate Unrestricted Weight Bearing MORPHINE NAPROXEN
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Digitally Mapping the Hydro-Topographical Context for Community Planning: A Case Study for the Upper Choapa River Watershed in Chile
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作者 Gustavo Moran Pedro Paolini Cuadra +2 位作者 Valenty Gonzalez John-Paul Arp Paul A. Arp 《Journal of Geoscience and Environment Protection》 2017年第3期265-277,共13页
Urban and non-urban settlements in many regions are usually located on the lands bordering shores, rivers, canals or streams. However, housing complexes, landfills, and areas for agriculture and mining are often assig... Urban and non-urban settlements in many regions are usually located on the lands bordering shores, rivers, canals or streams. However, housing complexes, landfills, and areas for agriculture and mining are often assigned to locations without sufficiently detailed hydrographic information about subsequent potential if not actual flow and flooding impacts. Yet, for sustainable community planning with emphasis on harmonizing social, economic, environmental and institutional aspects, such information is essential. This article demonstrates how this need can in part be accommodated by way of digital elevation and wet-area modelling and mapping using the upper component of the Choapa watershed in Chile as a case study. The terrain of this area has sharply incised valleys, with communities, fields and roads strung narrowly along the Choapa River and its tributaries. Above these locations along the Estero de Los Pelambres near the Chile-Argentina border are major mining and mineral refining activities. This article provides modelling and mapping details about the wet-to-moist area zonation along the upper Choapa River valleys, and addresses some of the mining-induced changes from 2000 to 2010. 展开更多
关键词 Digital Elevation Modelling Flow-Channel and Wet-Areas MAPPING Communications Mining Land-Use SETTLEMENTS HYDROLOGICAL CONCERNS
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生物等效研究与生物豁免的几点考虑
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作者 TENG Ren-li 《中国临床药理学与治疗学》 CAS CSCD 2007年第10期1189-1190,共2页
Bioequivalence is a critical tool that links the results of clinical studies to the pharmaceutical products that have undergone various manufacture changes. Although in vivo BE studies are still regarded as the "... Bioequivalence is a critical tool that links the results of clinical studies to the pharmaceutical products that have undergone various manufacture changes. Although in vivo BE studies are still regarded as the "gold standard" for evaluating the therapeutic equivalence of pharmaceutically equivalent drug products, in vitro testing as a sufficiently reliable surrogate for an in vivo BE study (biowaiver) has been increasingly accepted by regulatory agencies for some drug products. The guidances and regulations on biowaivers for oral solid dosage forms have facilitated the application of the biowaiving approach in formulation development for a new drug product, line extensions, a generic drug product development and post-approval changes both for innovator and generic drug products. Although biowaivers have demonstrated to reduce the drug development time and cost, the regional regulatory differences in the current requirements for biowaivers may complicate the decision to take the biowaiver approach. Time to file a biowaiver request to obtain a formal approval from the agency may be too long to risk project timelines, especially in the late stages of development. Since Japan does not accept the BCS based biowaiver, a decision to use the approach in the US and EU may present future issues for registration in Japan. The agreed BE strategy with one agency may not always work with another authority, which may result in a BE study for a region and a biowaiver request from another. When biowaivers are being considered as part of registration strategy, the different regulatory requirements for biowaivers, the time and expense of conducting in vivo BE studies versus the application for biowaiver and the overall impact on product development costs and timeline must be carefully considered and balanced. 展开更多
关键词 生物豁免 生物等效性 制药学 临床研究
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Weight Loss Impact on Change in Depression in Type 2 Diabetes Mellitus: Study to Help Improve Early Evaluation and Management of Risk Factors Leading to Diabetes (SHIELD)
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作者 Susan Grandy Andrew J. Green Kathleen M. Fox 《Journal of Diabetes Mellitus》 2014年第3期216-224,共9页
Objectives: This study evaluated the association between weight loss and change in depression among patients with type 2 diabetes mellitus (T2DM). Methods: Weight change from 2008 to 2009 among respondents (with and w... Objectives: This study evaluated the association between weight loss and change in depression among patients with type 2 diabetes mellitus (T2DM). Methods: Weight change from 2008 to 2009 among respondents (with and without T2DM) in the Study to Help Improve Early evaluation and management of risk factors Leading to Diabetes (SHIELD) was calculated. Change in depression was calculated as change from 2008 to 2009 in Patient Health Questionnaire-9 (PHQ-9) scores. Respondents with weight loss (>1%, >3%, >5%) were compared with respondents with weight gain (≥1%). Multivariate regression adjusted for baseline characteristics. Results: Among those with T2DM, more respondents with weight loss (n = 779) improved their depression scores, compared with respondents with weight gain (n = 731): 32.9%, 36.9%, 39.8% for >1%, >3%, and >5% weight loss, respectively, vs. 28.7% for weight gain (p<0.05). More respondents with weight loss improved the severity level of depression compared with respondents with weight gain (p < 0.05). After adjustment, T2DM respondents with weight loss had significantly greater improvement in depression scores (p < 0.05) and had 2 - 3 times higher odds of improving depression severity than T2DM respondents with weight gain (OR: 2.22 for >1%, 2.96 for >3%, and 3.31 for >5% weight loss, p < 0.01). Similar improvement in depression scores and severity of depression related to weight loss was observed among all SHIELD respondents (with and without T2DM). Conclusions: Our findings demonstrate an association between weight loss and improvement in depression over a 1-year period in adults with T2DM, and suggest the need for further investigation with respect to causality. 展开更多
关键词 DEPRESSION Type 2 DIABETES MELLITUS Weight Loss
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May-Thurner syndrome: High output cardiac failure as a result of iatrogenic iliac fistula
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作者 Shantanu Singh Shivank Singh +1 位作者 Juthika Jyothimallika Teresa J Lynch 《World Journal of Clinical Cases》 SCIE 2015年第3期318-321,共4页
May-Thurner syndrome(MTS) also termed iliocaval compression or Cockett-Thomas syndrome is a common, although rarely diagnosed, condition in which the patient has an anatomical variant wherein theright common iliac art... May-Thurner syndrome(MTS) also termed iliocaval compression or Cockett-Thomas syndrome is a common, although rarely diagnosed, condition in which the patient has an anatomical variant wherein theright common iliac artery overlies and compresses the left common iliac vein against the fifth lumbar spine resulting in increased risk of iliofemoral deep venous thrombosis. This variant has been shown to be present in over 23% of the population but most go undetected. We present a patient with MTS who developed high output cardiac failure due to an iatrogenic iliac fistula. The patient underwent an extensive workup for a left to right shunt including MRI and arterial duplex in the vascular lab. He was ultimately found to have a 2.1 cm left common iliac artery aneurysm and history of common iliac stent. We took the patient to the operating room for aortogram with placement of an endovascular plug of the left internal iliac artery and aorto-biiliac stent graft placement with CO2 and Ⅳ contrast. Subsequently the patient underwent successful stent placement in the area that was compressed followed by 6 mo of anticoagulation with warfarin. The flow from the fistula decreased significantly. 展开更多
关键词 May-Thurner SYNDROME Cardiac failure ECHOCARDIOGRAM Cockett-Thomas SYNDROME Iliocaval compression
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Effect of application rate and irrigation on the movement and dissipation of indaziflam
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作者 Amir M.Gonzalez-Delgado Manoj K.Shukla +1 位作者 Jamshid Ashigh Russ Perkins 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第1期111-119,共9页
Indaziflam is a new preemergence herbicide for the control of annual grass and broadleaf weeds in various cropping systems including pecan orchards.The objectives of this study were to(1) determine the mobility and ... Indaziflam is a new preemergence herbicide for the control of annual grass and broadleaf weeds in various cropping systems including pecan orchards.The objectives of this study were to(1) determine the mobility and dissipation of indaziflam and(2) evaluate herbicide efficacy in a flood-irrigated pecan orchard in southern New Mexico,USA.Indaziflam was applied at 0,35.5,and 73.1 g/ha in areas with(impacted) and without(unimpacted) tree injury symptoms.Soil samples were collected at 0-15,15-30,and 30-46 cm depths 25,63,90,and 125 days after the first herbicide application.Additional soil samples were collected 4,30,and 55 days after the second application.Indaziflam was detected in soil samples collected at each depth,suggesting movement with irrigation water.Indaziflam concentrations decreased with increasing soil depth and time.Indaziflam mass recoveries were greater in the unimpacted area than in the impacted area after the first and second applications.Dissipation half-lives of indaziflam in the soil ranged from 30 to 85 days for total indaziflam recovered from the entire soil profile after the first and second applications in both areas.The percent weed control was similar in the impacted and unimpacted areas for both rates of indaziflam on 25 and 53 days after application;however,on 90 days after the application,percent weed control was lower in the impacted than unimpacted area. 展开更多
关键词 Indaziflam Half-life Sorption Soil properties Dissipation Persistence
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PREPARATION OF 3~H-LABELLED 3-(β-PHENYLETHYL)-9β-METHOXY-9α-(m-PROPIONOXYPHENYL)-3-AZABICYCLO [3.3.1] NONANE AND SOME CHARACTERIZATIONS OF ITS BINDING WITH OPIATE RECEPTOR FROM RAT BRAIN
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作者 周德和 李志毅 +4 位作者 倪崇虎 吴益芝 池志强 唐国忠 钱宝根 《Chinese Science Bulletin》 SCIE EI CAS 1985年第3期412-416,共5页
We have reported that 3-(β-phenylethyl)-9β-methoxy-9α-(m-propionoxyphenyl)-3-azabicyclo [3.3.1] nonane (coded name; P-7548) was a new potent analgesic. Its potency was 2000 times that of morphine (mice, Lp., hot pl... We have reported that 3-(β-phenylethyl)-9β-methoxy-9α-(m-propionoxyphenyl)-3-azabicyclo [3.3.1] nonane (coded name; P-7548) was a new potent analgesic. Its potency was 2000 times that of morphine (mice, Lp., hot plate). Pharmacological tests further proved that P-7548 characterized its high potency, rapid onset and long 展开更多
关键词 MORPHINE METHOXY ANALGESIC potent AZABICYCLO METHOXY-9 PHENYLETHYL antag coded hydroxyphenyl
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Community Pharmacist-Based Collaborative Disease Management Program for Patients with Poorly Controlled Diabetes
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作者 Sujit S. Sansgiry Shivani K. Mhatre +3 位作者 Harshali K. Patel J. DavidHayes Kim Roberson Clyde J. James 《Journal of Health Science》 2015年第4期150-157,共8页
Objective: Patients with poorly controlled diabetes have more medical complications and are more difficult to manage. The objective of the present study was to evaluate the clinical outcomes of successful implementat... Objective: Patients with poorly controlled diabetes have more medical complications and are more difficult to manage. The objective of the present study was to evaluate the clinical outcomes of successful implementation of an employer initiated community pharmacist-based disease management program for diabetic patients with poorly controlled diabetes. Methods: Employees with poorly controlled diabetes (glycosylated hemoglobin (A1 C) level 〉 7.5%) were identified fi'om a large diabetes disease management program, in a rural setting in Texas, US. A longitudinal retrospective study was conducted, analyzing clinical indicators in the diabetes patients following the community pharmacist-based disease management program. The program involved a comprehensive drug therapy assessment and individualized disease management education. Primary outcome measured in the present study was A1C levels, assessed at the baseline visit and at the end of the intervention. Results: A total of 64 patients with poorly controlled diabetes were identified. Significant improvement in mean clinical outcome scores was achieved for A1C levels (p = 0.0011). At the end of the 1 year longitudinal intervention, targeted body mass index and A1C goals were attained by 35.9% (p 〈 0.001) and 15.6% patients, respectively. The 10 patients reaching goal levels post intervention were in the group that had baseline A1C of 7.5 to 9%. However, patients with 〉 9% A1C levels at baseline had a significant reduction (mean 2.1, p 〈 0.001) post intervention. Conclusion: The community pharmacist-based diabetes disease management program improved A1C levels of patients with poorly controlled diabetes. 展开更多
关键词 Poorly controlled diabetes community pharmacist INTERVENTION diabetes disease management program rural.
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Establishing a Hydrographic Framework for Watershed Management across Northern Chile
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作者 Gustavo Moran Pedro Paolini Cuadra +1 位作者 John-Paul Arp Paul A. Arp 《Journal of Geographic Information System》 2018年第5期539-561,共23页
This article demonstrates how currently available digital elevation (NASA SRTM;30 m resolution) and hourly global precipitation data (rain, snow;5 and 10 km resolution) can be used to hydrographically quantify the reg... This article demonstrates how currently available digital elevation (NASA SRTM;30 m resolution) and hourly global precipitation data (rain, snow;5 and 10 km resolution) can be used to hydrographically quantify the regional watershed management context across northern Chile. This is done through comprehensive derivations of flow direction, flow accumulation, flow channels, floodplain extent, depressions, and upslope watershed outlines. In turn, these derivations allow for estimating potential precipitation accumulations within any watershed, and turn these into subsequent storm-averaged discharge estimates at, e.g., at any road—flow-channel crossing points. This article elaborates on this by modelling and mapping hydrological conditions and subsequent storm damage at the regional scale and at select locations in terms of recent flood events on March 2015, May 2017, and June 2017. It was found that modelled flood extent and storm-estimated discharge volumes and rates generally conform to reported values including storm-caused damages within communities along the Huasco, Elqui, Limari, Copiapó and Salado rivers. This included the storm response assessment of six water reservoirs as these varied, as quantified, from normal (Puclaro, La Laguna, Cogoti), at capacity (La Paloma, Cogoli), and overflowing (Recoleta). The details of the local to regional assessments are presented in the form hydrologically explicit maps, figures and tables. Together, these attest to the general validity of the framework as introduced. Hydrometrically based stream-discharge calibrations would assist in further refining the approach, especially in terms of estimating local to regional run-off coefficients. 展开更多
关键词 NORTHERN Chile Watersheds Precipitation Digital ELEVATION Modelling Hydrographic INTERPRETATIONS STORM EVENTS
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Biobased Aromatic-Aliphatic Polyols from Cardanol by Thermal Thiol-Ene Reaction
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作者 Maha LShrestha Mihail Ionescu +3 位作者 Xianmei Wan Nikola Bilic′ Zoran SPetrovic′ Tom Upshaw 《Journal of Renewable Materials》 SCIE 2018年第1期87-101,共15页
Cardanol is a natural phenol which is obtained from high vacuum distillation of cashew nut shell liquid.It contains a hydrocarbon chain of 15 carbon atoms in the meta position,either with one,two or three nonconjugate... Cardanol is a natural phenol which is obtained from high vacuum distillation of cashew nut shell liquid.It contains a hydrocarbon chain of 15 carbon atoms in the meta position,either with one,two or three nonconjugated double bonds.This article describes thermal thiol-ene reaction to synthesize new cardanol-based polyols for polyurethanes with aromatic-aliphatic structure.Phenolic hydroxyl group was blocked by alkoxylation and 2-mercaptoethanol was added to the double bonds of propoxylated cardanol.The resultant product is a mixture of polyols that may contain one,two,three or four hydroxyl groups,as a function of the number of double bonds reacted with 2-mercaptoethanol.Similar polyols,but with much higher functionality,were also synthesized from condensation of cardanol-based novolacs with formaldehyde.These cardanolbased polyols were further utilized to prepare rigid polyurethane foams(PUs)with excellent physical and mechanical properties,useful for various applications in chemical and food industries. 展开更多
关键词 THIOL-ENE MERCAPTANS cashew nut shell liquid polyurethanes
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Disjunct Populations of a Locally Common North American Orchid Exhibit High Genetic Variation and Restricted Gene Flow
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作者 Madhav Pandey Jyotsna Sharma 《Open Journal of Genetics》 2015年第4期159-175,共17页
Whether the persistence of natural plant populations is limited by genetic diversity, gene flow, or other ecological and evolutionary factors is an important question in plant population genetics. An assessment of the... Whether the persistence of natural plant populations is limited by genetic diversity, gene flow, or other ecological and evolutionary factors is an important question in plant population genetics. An assessment of the distribution of genetic variation within and among populations is thus useful for understanding broad-scale gene flow patterns in plants with diverse pollination syndromes. We studied Pogonia ophioglossoides (L.) Ker Gawl., which is self-compatible but a primarily outcrossing species in the Tribe Pogonieae in the family Orchidaceae. Using three self-developed, highly polymorphic nuclear microsatellite (simple sequence repeat, or SSR) markers and two chloroplast microsatellites, we assessed genetic variation in eight populations representing its natural distribution. Relatively high within-population genetic variation (mean An = 9.08, Ho = 0.44, and He = 0.71) was detected in P. ophioglossoides. Eleven different alleles and 13 unique haplotypes were detected for two cpDNA microsatellites. Genetic differentiation based on the hierarchical AMOVA showed that 21% (ФPT = 0.21, P = 0.000) and 63% (ФPT = 0.63, P = 0.000) of the nuclear and cpDNA microsatellite allelic diversity, respectively, was distributed among populations. Pairwise FST values ranged from 0.041 to 0.224 and each was statistically significant at P ≤ 0.05. The isolation by distance estimate did not show an association between genetic differentiation and geographic distance indicating that populations were diverging independently. We documented fine-scale spatial genetic structure (FSGS) up to 40 m distance in Texas. Overall, gene flow across the sampled populations of P. ophioglossoides appears restricted, and the short-distance SGS suggests localized seed dispersal in this locally common North American terrestrial orchid. 展开更多
关键词 CPDNA Genetic Diversity Microsatellites Population Differentiation
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低压开关器件在成套设备主电路应用中的实际载流能力试验
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作者 夏欣荣 《电气时代》 2015年第9期77-79,共3页
阐述了成套设备温升试验的必要性;举例说明了新断路器集成在已经过试验验证的低压成套设备中所需采取的温升试验的过程,方法以及推导演算公式。塑壳断路器是最常见的低压开关器件之一,除了与接触器和热继电器配合使用在电动机,同时还由... 阐述了成套设备温升试验的必要性;举例说明了新断路器集成在已经过试验验证的低压成套设备中所需采取的温升试验的过程,方法以及推导演算公式。塑壳断路器是最常见的低压开关器件之一,除了与接触器和热继电器配合使用在电动机,同时还由于其操作维护方便而越来越多的替代熔断器隔离开关应用在馈电回路中。 展开更多
关键词 低压开关 试验回路 载流能力 热继电器 温升试验 隔离开关 型式试验 馈电 西门子公司 温升值
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