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81.
木耳菌丝体及其醇提物的药理作用   总被引:2,自引:0,他引:2  
木耳菌丝体小鼠ip给药能明显提高外周血T淋巴细胞百分率,使环磷酰胺引起的半数溶血值HC50减少恢复正常;其醇提物体内外均能明显抑制ADP诱导大鼠血小板聚集作用,缩短小鼠红细胞电泳时间。  相似文献   
82.
Objective: This study was designed to investigate the protective effects of didymin (Did) on doxorubicin (DOX)-induced cardiotoxicity. Methods: After pretreatment with Did (2, 4, 8 mg/kg intraperitoneal i.p.) for 7 d, the male C57 mice were injected with single dose of DOX (20 mg/kg i.p.). The cardioprotective effect of Did was observed on the 7th day after DOX treatment. Results: DOX delayed body growth and caused cardiac tissue injury, oxidative stress, and mitochondrial dysfunction. Similar experiments in H9C2 cardiomyocytes showed that DOX reduced cell viability, increased generation of reactive oxygen species (ROS) and fragmentation of DNA, decreased mitochondrial membrane potential, and induced cardiomyocyte apoptosis. However, all of these adverse effects were suppressed by Did pretreatment. Did increased protein expression of glutamate-L-cysteine ligase catalytic subunit (GCL), heme oxygenase 1 (HO-1), and nuclear factor erythroid 2-related factor 2 (Nrf2). Besides, Did also induced activation of PI3K/AKT. Conclusion: These findings indicated Did prevented DOX-induced cardiac injury and apoptosis via activating PI3K/AKT/Nrf2 signaling pathway.  相似文献   
83.
"现代中药"是我国实施中药现代化而催生的具体产业方向。中药标准化提取物是现代中药的一种产品形式,中药提取过程是中药现代化的重要技术环节,提取物在国际市场上的应用是中药国际化的先行者和铺路石。中药提取物应是中药的一种产品方式。建议国家主管部门的产业发展规划与工作部署中应提高对涉及中药生产过程控制(中药材种植、提取工艺、装备及辅料应用)产业化项目的关注度,积极促进以中药标准化提取物投料的现代中药和保健品的开发研究和生产销售。  相似文献   
84.
大鼠视神经钳伤后外侧膝状体细胞损伤的研究   总被引:8,自引:1,他引:8  
Zeng M  Wang N  Wu H  Chen J  Fan Z 《中华眼科杂志》2002,38(5):308-310,I006
目的 探讨大鼠视神经钳伤后 ,外侧膝状体 (lateralgeniculatebody,LGB)细胞的损伤情况。方法 用 4 0g视神经损伤钳 ,压迫Sprague Dawley(SD)大鼠双侧视神经 30s,制成视神经部分定量损伤的动物模型。对LGB连续梯度切片 ,7d后用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法 (teriminaldeoxynucleotidyltransferase mediateddUTPnickend labeling ,TUNEL)对LGB细胞进行凋亡检测。 1个月后通过免疫组化染色技术 ,用兔抗鼠神经丝 (neurofilament,NF)单克隆抗体对LGB的神经元进行检测。同时经视觉中枢注入荧光染料颗粒蓝 ,对LGB细胞进行逆行荧光标记 ,在 70 0nm波长荧光显微镜下对连续切片的LGB标记细胞进行平均密度计数 ,并与对照组比较。结果 TUNEL法染色证实LGB细胞发生凋亡。对照组神经丝免疫组化染色呈清晰的条索状 ,而实验组明显减少。对照组LGB细胞密度均值为 (5 172± 2 4 8)个 /mm2 ,而损伤组LGB细胞密度均值为 (414 4± 6 1)个 /mm2 ,两组比较差异有非常显著意义 (t=8 995 ,P <0 0 1)。结论 在大鼠视神经钳伤后 ,LGB细胞受损 ,其损伤机制与凋亡有关  相似文献   
85.
IntroductionCommunity‐acquired pneumonia (CAP) is the major cause of infection‐related mortality worldwide. Patients with CAP frequently present with admission hyperglycemia.ObjectivesThe aim of this study was to evaluate the association between admission blood glucose (ABG) level and clinical outcomes in elderly CAP patients (≥80 years of age) with or without diabetes.MethodsIn this single center retrospective study, 290 elderly patients diagnosed with CAP were included. Demographic and clinical information were collected and compared. The associations between admission blood glucose level and the 30‐day mortality as well as intensive care unit (ICU) admission and invasive mechanical ventilation (IMV) in elderly CAP patients with or without diabetes were assessed.ResultsOf the 290 eligible patients with CAP, 159 (66.5%) patients were male, and 64 (22.1%) had a known history of diabetes at hospital admission. After adjusting for age and sex, the logistic regression analysis had identified several risk factors that might be associated with clinical outcomes in elderly patients with CAP. Multivariable logistic regression analysis revealed that admission glucose level > 11.1 mmol/L was significant associated with ICU admission, IMV, and 30‐day mortality both in non‐diabetic and diabetic patients. Furthermore, Kaplan–Meier analysis indicated that patients with higher admission glucose level were correlated statistically significantly with 30‐day mortality in patients with CAP (P < 0.001).ConclusionAdmission blood glucose is correlated with 30‐day hospital mortality, ICU admission, and IMV of CAP in elderly patients with and without diabetes. Specially, admission glucose > 11.1 mmol/L was a significant risk factor for 30‐day hospital mortality.  相似文献   
86.
BackgroundCough is one of the most common symptoms of coronavirus disease 2019 (COVID-19). However, the prevalence of persistent cough in recovered patients with COVID-19 during a longer follow-up remained unknown. This study aims to investigate the prevalence, and risk factors for postinfectious cough in COVID-19 patients after discharge.MethodsWe conducted a follow-up study for 129 discharged patients with laboratory-confirmed COVID-19 in two large hospitals located in Hubei Province, China from January 2020 to December 2020. Baseline demographics, comorbidities and smoking history were extracted from the medical record. Current symptoms and severity were recorded by a uniform questionnaire. Spirometry, diffuse function and chest computed tomography (CT) were performed on part of patients who were able to return to the outpatient department at follow-up.ResultsThe median (interquartile range) follow-up time was 8.1 (7.9–8.5) months after discharge. The mean (standard deviation) age was 51.5 (14.9) years and 57 (44.2%) were male. A total of 27 (20.9%) patients had postinfectious cough (>3 weeks), 6 patients (4.7%) had persistent cough by the end of follow-up, including 3 patients with previous chronic respiratory diseases or current smoking. Other symptoms included dyspnea (6, 4.7%), sputum (4, 3.1%), fatigue (4, 3.1%), and anorexia (4, 3.1%) by the end of follow-up. Thirty-six of 41 (87.8%) patients showed impaired lung function or diffuse function, and 39 of 50 (78.0%) patients showed abnormal CT imaging. Patients with postinfectious cough demonstrated more severe and more frequent cough during hospitalization (P<0.001), and more chronic respiratory diseases (P=0.01). In multivariate logistic regression analysis, digestive symptoms during hospitalization [odds ratio (OR) 2.95, 95% confidence interval (CI): 1.10–7.92] and current smoking (OR 6.95, 95% CI: 1.46–33.14) were significantly associated with postinfectious cough of COVID-19.ConclusionsA small part of patients developed postinfectious cough after recovery from COVID-19, few patients developed chronic cough in spite of a higher proportion of impaired lung function and abnormal lung CT image. Current smoking and digestive symptoms during hospitalization were risk factors for postinfectious cough in COVID-19.  相似文献   
87.
背景 酒精使用障碍(AUD)是常见的慢性复发性精神疾病,对于重度AUD,需早期快速识别并及时妥善处理,以避免不可逆的伤害发生。目前,对AUD严重程度的评估主要基于临床医师对患者的精神检查,关于AUD严重程度影响因素及预测模型的研究有限。目的 分析AUD患者疾病严重程度的影响因素,构建风险预测模型,为评估AUD患者的疾病严重程度提供参考。方法 回顾性选取2017年1月1日—2022年12月31日南宁市第五人民医院收治的、符合《精神障碍诊断与统计手册(第5版)》(DSM-5)AUD诊断标准的1 358例首次住院患者为研究对象,收集其基本资料,根据疾病严重程度分为轻中度组(n=330)和重度组(n=1 028)。按7∶3将患者分为训练集和测试集,在训练集样本中构建Logistic回归模型,在测试集样本中采用受试者工作特征(ROC)曲线分析该模型对AUD严重程度的预测价值。结果 与轻中度组相比,重度组居住地在城市(χ2=7.804)、农民(χ2=17.991)、饮酒频率高于1~2次/天(χ2=35.267)的比例更高,初次饮酒年龄更大(t=-3.858),合并躯体疾病数量更多(Z=-22.782),γ-谷氨酰胺转移酶(χ2=259.940)和总胆红素异常(χ2=148.552)的比例更高(P均<0.01)。在训练集中进行的Logistic分析结果表明,农民(OR=2.024,95% CI:1.352~3.029)、初次饮酒年龄较大(OR=1.075,95% CI:1.025~1.129)、用餐时间外也饮酒(OR=3.988,95% CI:2.408~6.606)、总胆红素水平异常(OR=1.034,95% CI:1.000~1.069)、合并更多的躯体疾病(OR=4.386,95% CI:2.636~7.298)是AUD更严重的危险因素。该模型在测试集中的ROC曲线下面积(AUC)为0.906。结论 在精神专科医院中,农民、初次饮酒年龄较大、用餐时间外也饮酒、总胆红素水平异常、合并更多的躯体疾病可能是重度AUD的危险因素。  相似文献   
88.
Fracturing pumpheads are typical pressure vessels that experience frequent fatigue failure under the effect of notches in their cross-bore. To enhance the fatigue life of fracturing pumpheads, the study of the notch effect is indispensable and important to establish a reliable mathematical model to predict their fatigue life. In the present paper, two novel fatigue life prediction models are proposed for notched specimens. In these models, two new geometric fatigue failure regions are defined to improve the weight function. Finally, the elaborated novel stress-field intensity approach was applied to three different types of notched specimens. Experiment results indicate that the new SFI approach achieves 47.82%, 39.48%, and 31.85% higher prediction accuracy than the traditional SFI approach, respectively. It was found that the modified SFI approach provided better predictions than the traditional SFI approach and the TCD method. The II-th novel SFI approach had the highest accuracy, and the I-th novel SFI approach was more suitable for sharply notched specimens.  相似文献   
89.
Objective: Osteoporosis (OP) is the most common bone disease. The genetic and metabolic factors play important roles in OP development. However, the genetic basis of OP is still elusive. The study aimed to explore the relationships between OP and dietary habits. Methods: This study used large-scale genome-wide association study (GWAS) summary statistics from the UK Biobank to explore potential associations between OP and 143 dietary habits. The GWAS summary data of OP included 9434 self-reported OP cases and 444,941 controls, and the GWAS summary data of the dietary habits included 455,146 participants of European ancestry. Linkage disequilibrium score regression (LDSC) was used to detect the genetic correlations between OP and each of the 143 dietary habits, followed by Mendelian randomization (MR) analysis to further assess the causal relationship between OP and candidate dietary habits identified by LDSC. Results: The LDSC analysis identified seven candidate dietary habits that showed genetic associations with OP including cereal type such as biscuit cereal (coefficient = −0.1693, p value = 0.0183), servings of raw vegetables per day (coefficient = 0.0837, p value = 0.0379), and spirits measured per month (coefficient = 0.115, p value = 0.0353). MR analysis found that OP and PC17 (butter) (odds ratio [OR] = 0.974, 95% confidence interval [CI] = (0.973, 0.976), p value = 0.000970), PC35 (decaffeinated coffee) (OR = 0.985, 95% CI = (0.983, 0.987), p value = 0.00126), PC36 (overall processed meat intake) (OR = 1.035, 95% CI = (1.033, 1.037), p value = 0.000976), PC39 (spirits measured per month) (OR = 1.014, 95% CI = (1.011, 1.015), p value = 0.00153), and servings of raw vegetables per day (OR = 0.978, 95% CI = (0.977, 0.979), p value = 0.000563) were clearly causal. Conclusions: Our findings provide new clues for understanding the genetic mechanisms of OP, which focus on the possible role of dietary habits in OP pathogenesis.  相似文献   
90.
为了探讨突触素(SYN)在不同周龄阶段胎儿端脑额叶中的表达与胎儿额叶皮质突触发育的关系,本研究采用免疫组织化学方法观察突触素在不同周龄阶段胎儿额叶的表达水平,利用计算机图像分析技术测量不同周龄阶段胎儿额叶突触素表达的平均光密度;同时取材、常规电镜技术处理、透射电镜观察额叶突触发育的超微结构变化。结果显示:(1)光镜下各组均可见SYN免疫阳性产物主要表达于胎儿的额叶皮层,其表达量随周龄的增加而增强,各组间呈现显著性差异(P<0.05),其中16~24周胎儿额叶的阳性产物位于神经元的胞浆内,呈均匀的浅黄色,神经元突起内未见阳性产物;25~29周额叶的阳性产物呈黄色,在胞浆和突起内均可见,但阳性产物的量却下降;而30~39周额叶的SYN阳性产物呈棕黄色的点状或颗粒状,主要位于神经元的突起内,神经元胞浆内未见阳性产物,阳性产物的量显著增加;(2)透射电镜下19~36周胎儿大脑额叶均可见到突触样结构,随着周龄的增加,突触的数量逐渐增多,结构逐渐清晰和完整。上述结果提示SYN的表达可以反映胎儿神经系统发育的程度,SYN的表达与突触的发育是一致的;SYN在胎儿大脑额叶的表达部位经历由神经元胞浆内表达为主到神经元终末表达为主的这一过程,可能是由于SYN先是在神经元胞浆内合成,再随着神经元的发育而逐步转移到神经元突起的末梢部位。  相似文献   
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