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71.
Denervation of the synergists of the medial gastrocnemius (MG) muscle in the cat hind leg results in a progressive increase in the magnitude of burst activity in the MG muscle during walking. The increase in burst magnitude is associated with an increase in the slope of the relationship between the magnitude of individual MG bursts and the amplitude of ankle flexion during stance. This finding is consistent with the hypothesis that the increase in MG burst magnitude is due to an increase in gain of reflex pathways reinforcing the activation of MG. The increase in slope is use-dependent since it was not observed when the leg was released from a cast that immobilized the leg for 6 days.  相似文献   
72.
目的 :探讨豚鼠耳蜗部分外支持细胞 (Deiter细胞、Hensen细胞和外柱细胞 )的分离方法 ,并建立细胞活性的鉴别标准。方法 :选取健康杂色豚鼠 5只 ,解剖出耳蜗基底膜 ,采用酶解加机械吹打法分离Deiter细胞、Hensen细胞和外柱细胞。结果 :可以获得较多数量、活性良好、长短不一的Deiter细胞和Hensen细胞 ,8h内细胞活性较好 ;但外柱细胞数量较少 ,存活时间较短。评价Deiter细胞、Hensen细胞和外柱细胞的活性标准 :①细胞膜无膨胀或扭曲 ;②细胞核无肿胀、移位 ;③在相差显微镜下细胞呈半透明状态 ,存在双折射现象 ;④细胞内无呈布朗运动的颗粒。结论 :熟悉耳蜗的解剖特性、分离出完整的基底膜 ,增加酶的浓度和加大机械吹打力度是获取活性良好的Deiter细胞、Hensen细胞和外柱细胞的关键 ;评价外毛细胞活性的 4项标准同样可用于判断Deiter细胞、Hensen细胞和外柱细胞的活性  相似文献   
73.
尼可刹米生产工艺改进   总被引:2,自引:0,他引:2  
袁文福 《安徽医药》2004,8(1):74-75
菸酸与二乙胺、三氯氧磷作用,再经氢氧化钠中和,加入纯碱使反应液中的产品与水分层,取代有机溶剂萃取工艺,简化了操作,降低了消耗.  相似文献   
74.
目的探讨旋毛虫体细胞的分离方法和活性检测。方法将从小鼠肌肉分离、纯化的旋毛虫幼虫放入玻璃匀浆器匀浆,胰酶消化。锥虫蓝和中性红染色检测分离细胞的活性。结果分离的细胞中活细胞比率在90%以上。结论锥虫蓝和中性红染色,都能较好地检测细胞的活性。加胰酶消化后,死细胞数略有减少。旋毛虫的体细胞分离,可以不用加胰酶消化。  相似文献   
75.
高等医药教育人才培养模式的内涵及其动因   总被引:3,自引:0,他引:3  
叶志明 《药学教育》2005,21(3):5-7,15
探讨人才培养模式的基本内涵,对高等医药教育人才培养模式概念进行界定,并分析其基本特征和系统动因。  相似文献   
76.
77.
Recent progress has provided clear evidence that many RNA-viruses form cytoplasmic biomolecular condensates mediated by liquid–liquid phase separation to facilitate their replication. In contrast, seemingly contradictory data exist for herpesviruses, which replicate their DNA genomes in nuclear membrane-less replication compartments (RCs). Here, we review the current literature and comment on nuclear condensate formation by herpesviruses, specifically with regard to RC formation. Based on data obtained with human cytomegalovirus (human herpesvirus 5), we propose that liquid and homogenous early RCs convert into more heterogeneous RCs with complex properties over the course of infection. We highlight how the advent of DNA replication leads to the maturation of these biomolecular condensates, likely by adding an additional DNA scaffold.  相似文献   
78.
Steel is one of the most important industrial materials, which mainly comes from the smelting of iron ore. In view of the huge steel consumption every year, the exploitation of vast reserves of siderite ores is significant for improving the self-sufficiency rate of iron ore resources and ensuring the strategic security of the iron and steel industries. This paper investigated the influence of temperature, time, and other parameters on the magnetic properties of roasted siderite ores using the method of suspended roasting and analyzed the washability of roasted ores under weak-magnetic-field conditions using the magnetic separation tube experiment. The findings of the study explained the iron phase transformation process, i.e., FeCO3 was transformed into Fe3O4 by suspension magnetization roasting. Furthermore, the saturation magnetization of the roasted ore increased in due time at a constant temperature range of 550–750 °C and a roasting time of less than 5 s. It also increased with increasing temperature and constant time. The roasted ore achieved the best magnetic characteristics after roasting at 750 °C for 5 s. After low-intensity magnetic separation, the iron grade of the concentrate changed to 55.12%, with a recovery rate of 90.34%. The study results provide a reference for the development and application of siderite suspension magnetization roasting technology.  相似文献   
79.
目的:了解小学生气质特征和家庭教养方式,促进所有小学生身心健康全面发展.方法:2018年1月—2019年6月,随机抽取六盘山连片特困区400名小学生及家长,调查了解小学生气质特征、家庭教养方式,进行相关性分析.结果:气质维度中适应性得分最高,活动水平、趋避性、情绪本质和坚持性等,男、女生存在显著性差异(P<0.05)....  相似文献   
80.
This systematic review and meta-analysis elucidate the effects of the Japanese-style diet and characteristic Japanese foods on the mortality risk of cardiovascular disease (CVD), cerebrovascular disease (stroke), and heart disease (HD). This review article followed the PRISMA guidelines. A systematic search in PubMed, The Cochrane Library, JDreamIII, and ICHUSHI Web identified prospective cohort studies on Japanese people published till July 2020. The meta-analysis used a random-effects model, and heterogeneity and publication bias were evaluated with I2 statistic and Egger’s test, respectively. Based on inclusion criteria, we extracted 58 articles, including 9 on the Japanese-style diet (n = 469,190) and 49 (n = 2,668,238) on characteristic Japanese foods. With higher adherence to the Japanese-style diet, the pooled risk ratios (RRs) for CVD, stroke, heart disease/ischemic heart disease combined (HD/IHD) mortality were 0.83 (95% CI, 0.77–0.89, I2 = 58%, Egger’s test: p = 0.625, n = 9 studies), 0.80 (95% CI, 0.69–0.93, I2 = 66%, Egger’s test: p = 0.602, n = 6 studies), and 0.81 (95% CI, 0.75–0.88, I2 = 0%, Egger’s test: p = 0.544, n = 6 studies), respectively. Increased consumption of vegetables, fruits, fish, green tea, and milk and dairy products decreased the RR for CVD, stroke, or HD mortality. Increased salt consumption elevated the RR for CVD and stroke mortality. Increased consumption of dietary fiber and plant-derived protein decreased the RR for CVD, stroke, and HD/IHD mortality. The Japanese-style diet and characteristic Japanese foods may reduce CVD mortality. Most studies conducted diet surveys between 1980 and the 1990s. This meta-analysis used articles that evaluated the same cohort study by a different method. A new large-scale cohort study matching the current Japanese dietary habits is needed to confirm these findings.  相似文献   
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