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生物安全柜是重要的一级屏障设备,适当的控制方式对生物安全柜的防护能力是很重要的。文中主要介绍了生物安全柜的控制要点和几种控制方式及其特点。  相似文献   
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内镜辅助方型脸改型术   总被引:4,自引:0,他引:4  
目的探讨内镜在方型脸改型术中的临床应用效果。方法采用口内入路,在内镜辅助下,用高速涡轮气钻截除肥大下颌角、切除部分咬肌和颊脂垫,进行方型脸的面部改型。结果本组共38例,其中男3例,女35例,年龄21~40岁。内镜完全可以清楚显示下颌升支、下颌角、下颌体下缘,视野清晰。使用高速涡轮气钻截除肥大下颌角可以更加精确和容易,且创伤小,出血少,手术时间短,感染风险低。下面部轮廓改善满意。结论内镜辅助方型脸改型术,有助于获得良好的手术效果。  相似文献   
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目的探讨衰老对大鼠阴茎组织结构、NO(nitric oxide)-cGMP(cvclic Guanosine Monophosphate)通路及端粒酶活性的影响作用。方法本课题以不同月龄大鼠阴茎组织及培养的平滑肌细胞为研究对象,检测不同月龄大鼠阴茎组织中NO量、NOS(Nitric Oxide Synthase)活性、cGMP量、端粒酶活性及海绵体结构的变化,并比较大鼠、人阴茎组织及大鼠原代海绵体平滑肌细胞的端粒酶活性。结果(1)大鼠阴茎组织中NO量、NOS活性均先升高后降低,各月龄组间有显著差异。阴茎组织cGMP含量逐渐降低,各月龄组间差别显著;(2)随龄增加,平滑肌纤维逐渐减少,胶原纤维增多,粗大成团,窦状隙变少、变窄:(3)大鼠阴茎组织端粒酶活性以2月龄活性最高,随龄增加逐渐下降。人阴茎组织中无端粒酶活性。结论(1)衰老对大鼠阴茎组织结构、NO.cGMP通路及端粒酶活性有显著影响,提示衰老与ED关系密切;(2)大鼠阴茎组织有端粒酶活性,可作为研究细胞衰老与ED关系有关端粒酶的模型。  相似文献   
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The effects of aging on diencephalic (A-11, A-12, A-13, A-14) catecholamine neurons in the F344 male rat were examined with Falck-Hill?rp histofluorescence. In contrast to the age-related increase in A-12 perikaryal fluorescence intensity previously reported (Hoffman and Sladek: Neurobiol. Aging 1:27-37, '80), incertohypothalamic perikarya showed decreased (A-13) or unchanged (A-11, A-14) fluorescence intensity with age. Cell counts of fluorescent A-12 perikarya disclosed a 47% increase in the number of fluorescent A-12 neurons in 30-month-old F344 rats relative to the 3-month-old controls; numbers of A-11 and A-13 fluorescent perikarya decreased with age, but the declines were not statistically significant. It is unlikely that the age-related increase in number of fluorescent A-12 perikarya is the result of proliferation of neurons in the aged F344 rat. Rather, the greater number of fluorescent A-12 perikarya in 30-month-old F344 rats indicates that some A-12 neurons in 3-month-old F344 rats contain levels of dopamine that are subthreshold for detection with the Falck-Hill?rp fluorescence technique, whereas virtually all A-12 perikarya in 30-month-old F344 rats contain detectable quantities of dopamine. These findings suggest that diencephalic catecholamine neurons exhibit divergent changes in transmitter content and cell number that may reflect varying degrees of functional integrity during brain aging.  相似文献   
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After the interaction of estrogen with the ligand binding domain (LBD) of mouse estrogen receptor‐α (mERα) and hormone‐responsive elements of target genes, many nuclear proteins are recruited to regulate the expression of specific genes. Because it is not known which brain proteins interact with LBD or whether these proteins vary with age and sex, we used pull‐down assay and far Western blotting to detect five nuclear proteins of 160, 140, 87, 60, and 46 kD in the mouse brain. These interacting proteins were identified as PELP1, RIP140, PGC1α, BAF60, and ADA3, respectively. The level of PELP1, RIP140, PGC1α, and BAF60 decreased drastically in old compared with adult male mice, whereas the ADA3 level showed no significant change. PELP1, PGC1α, and BAF60 levels were lower in old male compared with female mice. Thus we report the identification and interaction of five nuclear proteins with mERα‐LBD, indicating their role in estrogen signaling and brain functions during aging. © 2009 Wiley‐Liss, Inc.  相似文献   
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Aim:   In the last three decades, the segment of population aged 60 years and older has more than doubled in Brazil. People aged 80 years and older are expected to be the fastest-growing segment in the near future. This aim of this study was to analyze the legal structures currently in place in Brazil and to provide a framework for care policies and practices towards older-adults.
Methods:   This article focuses on past and present major socioeconomic burdens on this segment of the Brazilian population as well as on public achievements to overcome inequities.
Results:   Both the public health and the social security systems have been directed to provide preferential assistance to the aged. Nonetheless, the elderly remain the most impoverished segment of Brazil and carry the burden of an overall lack of specialized services. Moreover, socioeconomic inequalities and population diversity in Brazil affects elderly care, adding complexity to this unique scenario.
Conclusion:   Brazil has adopted legal hallmarks that substantially shifted public practices towards the elderly segment from a philanthropic status to a legitimate right for care and assistance. The demographic transition that took place provides an opportunity for innovative solutions in public policies for older adults in a developing economic environment.  相似文献   
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The present paper deals with a Finnish long-term prospective study, the objective of which is to shed light on adjustment to retirement and old age. In this phase, only the preliminary findings of the initial survey carried out in 1982 are available. For the purposes of the study, a random sample of 200 individuals was drawn from among Turku inhabitants born in 1920. Another sample, consisting of 189 persons of the same age, was drawn from rural municipalities in the neighborhood of Turku. An extensive structured psychosocial interview could be conducted with a total of 339 subjects. The research methods used included e.g. the 36-item version of Goldberg's General Health Questionnaire (GHQ). Relatively little mental disturbance was revealed in the interview, and no major differences occurred between the urban and the rural sample. Somewhat over one-third of both samples were probable psychiatric cases as defined according to the GHQ.  相似文献   
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