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71.
A random ethene/styrene copolymer containing 13.8 mol-% styrene was prepared with the Ziegler-Natta catalyst system Me2Si(Me4Cp)(N-t-butyl)TiCl2/methylaluminoxane and characterized by means of preparative temperature rising elution fractionation (TREF) combined with size exclusion chromatography, NMR, differential scanning calorimetry and wide-angle X-ray scattering analyses of the copolymer fractions. Efforts are made to describe the distribution of the styrene content of the copolymers using the Stockmayer-Tacx distribution function. Both, comonomer distribution and molar mass distribution strongly support the presence of a single type of catalytically active center.  相似文献   
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中风发病后6—9月的生命质量   总被引:9,自引:0,他引:9  
目的 比较发病后6-9月的中风患者与正常对照的健康差异,以明确针对中风患者的社区卫生服务应着手解决的健康问题。方法 对150例中风后6-9月的患者及按照性别、年龄、居住环境进行1:1配对的正常对照,采用SF-36进行健康自评,比较不同领域的健康状况。结果 患者生命质量在躯体功能、生理性角色功能受限、 社会功能、活力4个领域(P<0.01)随年龄的增加而降低。男性生命质量在总体健康(P=0.017)、躯体功能(P=0.015)、活力和精神健康(P<0.01)等4个领域好于女性。患者与对照比较,除了疼痛(P=0.289)领域外,患者生命质量的各个领域均差于对照(P≤0.001)。结论 患者以发病后6-9月时,除了存在严重的躯体功能障碍之外,还有严重的心理、社会功能障碍以及角色功能障碍。其中,精神健康和女性患者是工作重点。  相似文献   
74.
观察脑梗死(CI)患者神经肽Y(NPY)、神经降压素(NT)、胃动素(MTL)、降钙素基因 相关肽(CGRP)浓度变化及其临床意义。方法选择C162例,用放免法检测血浆NPY、NT、MTL与CGRP浓度。结果NPY、NT与MTL浓度显著高于对照组(P<0.0001);于发病后24h内显著升高,7d内达高峰,8~15d开始下降,15d后仍在较高水平。NPY浓度重型与大灶组显著高于轻型(P<0.05)与小灶组(P<0.01);发病积分≥6分组显著高于<6分组(P<0.05);高血压组显著高于正常血压组(P<0.05)。NT与MTL浓度重型组显著高于中(P<0.05)、轻型组(P<0.01);高血糖组显著高于正常血糖组(P<O.01)。CGRP浓度显著低于对照组(P<0.0001),发病24h内即显著降低,2~7d进一步降低,8~15d开始升高,15d后逐渐升至正常水平。重型与大灶组显著高于轻型(P<0.0001)、中型(P<0.01)与小灶组(P<0.01);伴发病积分≥6分组显著低于<6分组(P<0.05)。结论CI患者NPY、NT、MTL、CGRP浓度变化以7d内最显著,15d后逐渐恢复正常水平;四种浓度监测可作为判断CI患者病情严重程度、病灶大小及伴发病的实验室指标。  相似文献   
75.
采用化学共沉淀法制备锑掺杂二氧化锡(ATO)超细导电粉体,研究了反应温度,滴定终点pH值,掺锑量及锻炼温度对粉体导电性的影响,并对实验结果进行了讨论。  相似文献   
76.
以Maxwell-Bonnel图拟合式、对比态Antoine方程及Pitzer-Riedel关联式分别求算饱和蒸汽压P^0,并用RoultK值(K=P^0/P),计算窄留分K值。根据实测的中原、孤岛和克拉玛依石油馏分低压K值,考察上述三式,结果表明:对比态Antoine式预测精度是最好的,其温度预测绝对平均偏差为7.0℃,K值预测平均相对偏差为15.6%,其他两模型偏差均较大。  相似文献   
77.
Summary In order to study the clinical significance and change of interleukin (IL)-1β and IL-10 concentration in intestinal mucosal tissues in various stage of ulcerative colitis (UC), IL-1β and IL10 levels were measured by enzyme linked immunosorbent assays (ELISA). Our results showed that IL-β level caused by spontaneous secretion in the intestinal mucous tissues in active stage of ulcerative colitis was significantly higher than that in normal controls and in remission stage of ulcerative colitis (P <0. 01,P<0. 001). IL-10 level in various stage of UC was relatively lower in controls, but there was no significantly difference between the two groups. Our study suggested that higher IL-1β level in active might play an important role in pathogenesis of UC, and IL-10, as an anti-inflammatory cytokine, was low in active UC, suggesting that it may be a important factor contributing to the development of higher IL-1β level. This project was supported by the grant of the Scientific Research Fund of the Ministry of Health (No. 98-2-387).  相似文献   
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79.
The study was designed and conducted to evaluate the plant-based diet status and its association with erectile function (EF) in Chinese young healthy men. From July 2018 to May 2020, 116 objectively proved physically and psychologically healthy men were selected. Clinical questionnaires, detailed physical examinations and blood tests were all assessed. An overall plant-based diet index (PDI) and a healthful plant-based diet index (hPDI) were developed from each participant to measure plant-based diet quantitatively. The EF was measured by both the International Index of Erectile Function-5 (IIEF-5) and the surrogated measures of endothelial function, peripheral levels of nitric oxide (NO) and E-selectin. In subjects, the mean PDI and hPDI were 53.8 ± 8.2 and 54.7 ± 8.9 respectively. Results of multivariate analysis showed that both PDI and hPDI were negatively associated with BMI (all p < .05), but had no relationships with NO, E-selectin, TT levels and IIEF-5 scores (all p > .05). In a subgroup of male population, Chinese young healthy men, the plant-based diet, measured by PDI and hPDI, was not related to erectile function. The population can adhere to plant-based diet to keep healthy without concerns of negative influence on erectile function.  相似文献   
80.
BackgroundSeveral studies have reported that solid organ transplant recipients have a high risk for malignant tumors because the suppressed immune system fails in preventing malignant transformations. De novo malignancy after transplantation is the most common cause of death in the late period after liver transplant (LT). This study investigated the clinical significance of de novo malignancy after LT, and it is the largest study based in Korea to report long-term follow-up results associated with de novo malignancy after LT.MethodsData of 1793 adults who underwent LT in Seoul National University Hospital were retrospectively collected, and medical charts and data from the Ministry of Public Administration and Security were reviewed to examine the causes of death and de novo malignancy status. The Fisher exact test and Kaplan-Meier survival analysis were used to analyze the data.ResultsOf the 1793 recipients, 27 died of de novo malignancies. Of 875 hepatocellular carcinoma (HCC) patients, 12 died, and of 918 non-HCC patients, 15 died. De novo malignancy was the main cause of death at 5 years after LT but was not in the initial 5 years. In Korea the most common cancers that developed after LT were gastric cancer (21.4%) and lymphoma (14.3%). De novo HCC in non-HCC cases was found in 2 patients.ConclusionDe novo malignancy is a key factor affecting long-term survival after LT. Therefore, regular screening and education are important for improving long-term survival and quality of life in these patients after LT.  相似文献   
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