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81.
目的研究定位损伤脑胆碱能系Alzheimer病(AD)模型大鼠学习能力及相关脑神经肽免疫组化改变.方法用兴奋性毒素鹅膏蕈氨酸(IBA)定位损伤大鼠脑右侧Meynert核,观察模型动物学习能力改变(Y型迷宫法),并用分光光度法和免疫组化染色法观察动物脑胆碱酯酶(AchE)活性和皮层及海马β-淀粉样肽前体(β-APP)、生长抑素(SOM)及P物质(SP)的表达情况.结果模型组老化大鼠经损伤后,学习能力及脑AchE活性显著低于对照组(P均<0.05).β-APP在额叶皮层和海马的表达均升高,而S()M表达则显著减少,用IBA及β-AP25-35同时损伤鼠脑时,可显示脑皮质区SP表达增加(P均<0. 01).单独用IBA注射无效.结论IBA损伤老化大鼠脑Meynert核建立的动物模型,显示胆碱能系统损伤,学习能力障碍,β-APP过表达而神经肽SOM表达降低,一定条件下SP表达增加,与AD病人某些临床和病理特征基本一致.  相似文献   
82.
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   
83.
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   
84.
目的 :应用苄基二甲基十四烷氯化铵 (benzyldim ethyltetradecyl amm onium chloride,BAC)建立犬下食管括约肌(L ES)无神经动物模型 ,研究一氧化氮 (NO)对 L ES压力的作用。方法 :将 BAC环周注入犬 L ES,对照组注入等量生理盐水 ,均于注射前及注射后 6周测定 L ES压力 ;并观察 L -精氨酸、D -精氨酸、硝普钠及一氧化氮合酶 (NOS)抑制剂 N-硝基 - L -精氨酸 (L - NNA)对 L ES压力的影响 ;此外还测定了两组犬 L ES中 NO含量和 NOS活性。结果 :BAC处理组 L ES压力 [(4 2 .43±4.19) m m Hg,1m m Hg=0 .133 k Pa]显著高于对照组 [(2 2 .71± 5 .19) mm Hg]。 L -精氨酸可使对照组 L ES压力降低 ;L - NNA使其增高 ,但对 BAC处理组 L ES压力均无影响。硝普钠可降低两组犬 L ES压力。对照组 L ES中 NO为 (6 .0 5 8± 2 .0 6 7)μm ol/g,NOS为 (1.45 8± 0 .146 ) U /mg;而 BAC处理组 NO为 (1.797± 0 .873)μmol/g,NOS为 (0 .46 3± 0 .0 39) U /m g,均较对照组显著降低 (P<0 .0 1)。 结论 :BAC可使犬 L ES压力增高 ,其机制可能与 L ES局部 NO减少有关。  相似文献   
85.
86.
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   
87.
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   
88.
金奕  叶雪卫 《新中医》2023,55(9):85-88
目的:观察夏枯草颗粒联合甲巯咪唑片治疗毒性弥漫性甲状腺肿伴甲状腺功能亢进症患者的疗效及对血清成纤维细胞生长因子21 (FGF21)、促甲状腺素受体抗体(TR-Ab)水平的影响。方法:选择78例毒性弥漫性甲状腺肿伴甲状腺功能亢进患者为研究对象,随机分为对照组与观察组各39例。对照组接受甲巯咪唑片治疗,观察组在对照组基础上联合夏枯草颗粒治疗。比较2组临床疗效,比较2组治疗前后血清游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)、促甲状腺素(TSH)及FGF21、TR-Ab水平。结果:治疗前,2组血清FT3、FT4、TSH水平比较,差异无统计学意义(P>0.05);治疗后,2组血清FT3、FT4水平均降低(P<0.05),TSH水平升高(P<0.05),且观察组FT3、FT4水平低于对照组,TSH水平高于对照组(P<0.05)。治疗前,2组血清FGF21、TR-Ab水平比较,差异无统计学意义(P>0.05);治疗后,2组血清FGF21水平升高(P<0.05),TR-Ab水平降低(P<0.05),且观察组FGF21水平高于对照组(P<0.0...  相似文献   
89.
Purpose: As COVID-19 spreads globally and affects people''s health, there are concerns that the pandemic and control policies may have psychological effects on young people (age from 17 to 35 years). This psychological impact might vary in different countries, and thus we compared the prevalence of selfreported psychological distress, loneliness and posttraumatic stress symptoms (PTSS) among young people in the United Kingdom (UK) and China at the beginning of the COVID-19 pandemic. Methods: Data of this study came from two sources. One source was the first wave of COVID-19 study in Understanding Society, a special wave of the UK household longitudinal study, which provided the highquality, national-wide representative panel data. The sample comprised 1054 young people. The other source was an online survey on the mental health of 1003 young people from Shanghai, a highly developed area in China. The questionnaire included questions on the prevalence of common mental disorders (cut-off score ≥ 4), loneliness and potential PTSS (cut-off ≥ 33). Univariable analyses were conducted to test the differences in the self-reported prevalence of psychological distress and loneliness between the two groups. Multivariable logistic regression analyses were run to explore the predictors of psychological distress and loneliness among all the young people from England and Shanghai. Results: Among the samples with self-reported psychological distress, the UK sample accounted for 34.4% (n = 1054) and the Chinese sample accounted for 14.1% (n = 1003). The difference between the two groups was statistically significant (p < 0.001). Additionally, 57.1% of people in the UK and 46.7% in China reported that they sometimes or often felt lonely, of which the difference is statistically significant (p < 0.001). Regression analysis of the entire samples showed that nationality, gender, psychotherapy and loneliness were significant predictors of 12-item General Health Questionnaire scores, while the variables of age and living alone were not. Significant predictors of self-reported loneliness were the nationality, gender, age, living alone and psychotherapy. In China, 123 (12.3%) young people, 49 men (11.3%) and 74 women (13.0%), met the criteria of PTSS symptoms (cut-off scores ≥ 33). These scores were only collected in China. Conclusion: This evidence suggests that mental health and loneliness reported by young people were lower in China than that in the UK during the studied period. More research is needed to understand these differences. If the differential negative psychological impacts are confirmed, country-specific measures of prevention and intervention should be adopted to improve the mental health of young people under the ongoing impact of the pandemic.  相似文献   
90.
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