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91.
目的:探讨核糖蛋白2(ribophorin II,RPN2)在肝细胞肝癌(HCC)组织中的表达和对HCC患者生存的影响,同时分析RPN2对肝癌HepG2细胞生长和克隆形成的作用。方法:应用免疫组化方法和HCC公共芯片数据,从蛋白和m RNA水平检测HCC组织中RPN2的表达,同时分析RPN2与HCC患者临床参数的关系及预后相关性;进一步利用MTS法和克隆形成实验在肝癌HepG2细胞中检测RPN2对细胞生长的作用。结果:98例肝癌组织中,RPN2阳性表达率88.78%,对应癌旁肝组织中,RPN2阳性表达率74.49%;癌组织中RPN2染色评分为5.80±3.15,癌旁肝组织RPN2染色评分为2.13±1.59,肝癌组织中RPN2表达显著上调(P0.001)。3个肝癌公共芯片数据(共522例肝癌)中RPN2的m RNA表达水平同样显著升高(均P0.001)。98例肝癌患者RPN2表达水平与肿瘤直径(P=0.004)、门脉侵袭(P=0.012)和TNM分期(P=0.009)相关;RPN2高表达的患者总体生存期(OS)和无复发生存期(RFS)较RPN2低表达的患者短(OS:P=0.027;RFS:P=0.036)。肝癌HepG2细胞转染RPN2小干扰RNA后,细胞生长能力显著受抑制。结论:RPN2在肝癌中表达显著升高,RPN2的表达与肝癌的恶性进展有关,RPN2显著促进肝癌细胞生长。  相似文献   
92.
近自然森林作为城市植被恢复的重要模式,已在我国多地开展了实践,并衍生了新的造林模式。为评估不同近自然森林建设模式的群落恢复进程,本研究以上海城市裸地上重建的近自然森林为对象,通过长期监测两处分别应用原"宫胁法"与新"异龄复层落叶—常绿混交林"种植模式的近自然森林重建过程,从物种组成、垂直结构、生活型组成和目标恢复物种4个方面解析恢复动态。结果表明:两种造林模式恢复的近自然森林,随恢复进程其物种组成逐渐趋同,在十多年内已形成了落叶—常绿垂直混交结构;"异龄复层落叶—常绿混交林"造林模式可更好地促进常绿阔叶树种的恢复,尤其是常绿建群种红楠与小叶青冈。本研究证实了近自然森林恢复技术可以缩短亚热森林群落向演替后期发展的时间,以及新造林模式的有效性,为近自然森林技术的应用与实施提供了科学依据。  相似文献   
93.
In 1979 the opinions of Ontario psychiatrists were sought regarding the influence of the Ontario Health Insurance Plan (OHIP) on the practice of their specialty. Full replies to a 44-item questionnaire were received from more than half the certified psychiatrists in Ontario, half of whom had been in practice before the introduction of OHIP. Both satisfaction and uneasiness were expressed about most aspects of health insurance. Many of the 416 psychiatrists stated that OHIP had improved access to psychiatric care, providing a more socially diverse practice, especially with respect to psychotherapy. Only one quarter believed that OHIP constituted a major intrusion on the doctor-patient relationship, and the majority reported that OHIP had been beneficial to themselves as psychiatrists (70%) and to their patients (86%). Almost half reported having raised their concern about the confidentiality of OHIP records with their patients; the patients less often brought up the issue. Although most psychiatrists in practice before the introduction of OHIP reported no change in their conduct of psychotherapy, a minority reported a decrease in the duration of treatment and an increase in the frequency of missed appointments. Also noted was an increase in the number of referrals for consultation, which led at times to overutilization of these specialists'' services.  相似文献   
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This review summarizes recent work that focuses on the role of endogenous opioids (EOs) and opiate receptors in the control of food intake. Although the anorexic effect of opiate antagonists are now well accepted, the exact EO, site(s), and mechanism(s) of action remain to be established. However, accumulating evidence suggests that dynorphin, an endogenous ligand for kappa-type opiate receptors, is an important regulator (stimulant) of appetite. The roles of other EOs, such as beta-endorphin, are less clear. EOs appear to be involved in maintaining normal feeding behavior and are likely responsible for the overconsumption of fat in genetically obese and stressed subjects. Opiate antagonists block overconsumption of palatable foods, thus offering a promising approach to weight reduction for some overweight individuals. Anorexias may follow from a deficiency of kappa-type opioid activity, and surprisingly, can also result from excess opioid activity. Indeed, opiate antagonists of the mu type (naloxone) can enhance eating and weight gain in certain anorexic conditions. Therefore, it appears that excess opioid agonist activity may result in hyperphagia or anorexia (depending on the opiate receptor type). Finally, opiate antagonists may help normalize both types of pathological feeding states.  相似文献   
96.
The acrosome of the spermatozoa is the organelle involved in its penetration through the ova membranes during the fertilization process. Several features of this process are considered to be related to the fertilization events e.g. some substance coats outside the membrane. During the maturation process the spermatozoa of Conocephalus saltator develop a coat of tubules and filaments which overly some membrane regions in a specific array. The mature spermatozoa are seen to adhere in these regions and form threads of 20 cells long and five to six wide. It is suggested that the external coat plays a role in this 'sticking' phenomenon.  相似文献   
97.
The mechanism and role of influenza virus (IV)-induced pathogenesis of macrophages during respiratory infection are ill defined. Reported here are findings on IV-induced cytopathic effects (CPEs) for anin vitroexperimental system using the murine macrophage cell line J774.1. CPE was elicited by 0.2 or greater multiplicity of infection (m.o.i.). CPEs showed a lag of 6–8 h postinfection and occurred most rapidly between 6 and 12 h. J774.1 cells did not support productive IV replication, but immunofluorescence demonstrated that IV protein synthesis occurred. Light microscopy and DNA staining showed that after death cells had very condensed cytoplasm and nuclei. Cell remnants were surrounded by intact plasma membrane (PM) as demonstrated by exclusion of a membrane-impermeant dye. Time-lapse video microscopy recordings between 6 and 10 h postinfection showed sequential structural changes, including previously undescribed events. Notable changes were a rapid cytokinesis (zeiosis; “cell boiling”), followed by nuclear shrinkage, and an unusual transient blebbing of the PM. DNA fragmentation occurred after 12 h, producing a wide size range. UV-inactivated virus failed to induce CPEs, and CPE was blocked by amantadine.N-Acetylcysteine and pyrrolidine dithiocarbamate, but not other inhibitors of reactive oxygen intermediates, reduced or blocked the CPE. Most changes observed are those attributed to apoptotic processes rather than necrotic cell death. The kinetics and inhibitor effects suggest that IV infection and replication must be initiated to activate CPEs.  相似文献   
98.
A model for the coarse structure of paramyosin filaments   总被引:2,自引:0,他引:2  
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