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101.
Evidence on the association between insomnia symptoms and mortality is limited and inconsistent. This study examined the association between insomnia symptoms and mortality in cohorts from three countries to show common and unique patterns. The Finnish cohort comprised 6605 employees of the City of Helsinki, aged 40–60 years at baseline in 2000–2002. The Norwegian cohort included 6236 participants from Western Norway, aged 40–45 years at baseline in 1997–1999. The Lithuanian cohort comprised 1602 participants from the City of Palanga, aged 35–74 years at baseline in 2003. Mortality data were derived from the Statistics Finland and Norwegian Cause of Death Registry until the end of 2012, and from the Lithuanian Regional Mortality Register until the end of 2013. Insomnia symptoms comprised difficulties initiating sleep, nocturnal awakenings, and waking up too early. Covariates were age, marital status, education, smoking, alcohol, physical inactivity, obesity, diabetes, cardiovascular diseases, depression, shift work, sleep duration, and self‐rated health. Cox regression analysis was used. Frequent difficulties initiating sleep were associated with all‐cause mortality among men after full adjustments in the Finnish (hazard ratio 2.51; 95% confidence interval 1.07–5.88) and Norwegian (hazard ratio 3.42; 95% confidence interval 1.03–11.35) cohorts. Among women and in Lithuania, insomnia symptoms were not statistically significantly associated with all‐cause mortality after adjustments. In conclusion, difficulties initiating sleep were associated with mortality among Norwegian and Finnish men. Variation and heterogeneity in the association between insomnia symptoms and mortality highlights that further research needs to distinguish between men and women, specific symptoms and national contexts, and focus on more chronic insomnia.  相似文献   
102.
E. Soncini  A. Petit   《ITBM》2002,23(3):172
Regulations evolve and risks management becomes one of the biomedical engineers' preoccupations. Thus, risks are various, and consequently it is difficult to identify, to manage and to bring them under control. Furthermore, regulations exist for sectors like healthcare technology monitoring, but it is not the same thing for instance for the risks linked to the maintenance. Thus regulation in the sector of maintenance evolves and the decree of the 1st July law of health safety is going to modify the biomedical environment. The goal of this work is to study the tools and the methods of risks management that have been used for several years in the industrial field and to use them for some biomedical equipment like monitors or IV pumps. These methods adapted to these equipment will allow us to determine some appropriate rules of maintenance.  相似文献   
103.
Telomere length homeostasis is essential for the long-term survival of stem cells, and its set point determines the proliferative capacity of differentiated cell lineages by restricting the reservoir of telomeric repeats. Knockdown and overexpression studies in human tumor cells showed that the shelterin subunit TPP1 recruits telomerase to telomeres through a region termed the TEL patch. However, these studies do not resolve whether the TPP1 TEL patch is the only mechanism for telomerase recruitment and whether telomerase regulation studied in tumor cells is representative of nontransformed cells such as stem cells. Using genome engineering of human embryonic stem cells, which have physiological telomere length homeostasis, we establish that the TPP1 TEL patch is genetically essential for telomere elongation and thus long-term cell viability. Furthermore, genetic bypass, protein fusion, and intragenic complementation assays define two distinct additional mechanisms of TPP1 involvement in telomerase action at telomeres. We demonstrate that TPP1 provides an essential step of telomerase activation as well as feedback regulation of telomerase by telomere length, which is necessary to determine the appropriate telomere length set point in human embryonic stem cells. These studies reveal and resolve multiple TPP1 roles in telomere elongation and stem cell telomere length homeostasis.  相似文献   
104.
This article describes the setting up, funding and organization of an in-house equipment management service in the Bristol & Weston Health Authority. Existing resources were redeployed to form the present service. The range of equipment now maintained under the auspices of the Medical Physics Bioengineering Group has a capital value of £12 million. All work is costed and a charge made to the client for whom work is carried out. A team of 27 medical physics technicians and three graduate engineers are maintained from this source of income. This method of funding is now making way for a system of job costing which will provide a basis for comparison with an outside service.  相似文献   
105.
目的研究呼吸机部件失效模式和影响,分析比较不同时间段呼吸机部件失效发生和危害的变化情况。方法统计陆军军医大学大坪医院2012年和2016年呼吸机机故障数据,选取其中部件原因故障失效数据2012年52台,2016年26台,采用失效模式、影响及危害性分析进行分析,参考刘延武文章方法分为13种模式,以风险优先数(RPN)值定量确定呼吸机部件失效危害度并比较。结果 2012年呼吸机部件故障的发生率为43.6%,2016年呼吸机部件故障的发生率为16.4%。2016年因呼吸机部件故障失效发生数量和发生概率较2012年大幅度下降,RPN值下降的部件有空氧混合器(空气)、空氧混合器(氧气)、呼气流量传感器、湿化器、呼吸回路、电源、面板,下降值分别为-108、-120、-40、-14、-192、-64、-50;RPN值增加的部件为吸(呼)压力传感器、支架、显示器,增加值分别为180、12、48;其他部件为RPN值不变,整体呼吸机部件失效危害度下降。结论通过失效模式、影响及危害性分析RPN值计算可以有效掌握呼吸机各部件可靠性与失效危害度变化,结合应用分析与实际需求及时改进呼吸机预防性维护、使用维护培训和维修管理措施,可以保障呼吸机使用过程中的可靠性,提高使用安全性。  相似文献   
106.
An immunohistochemical method for assessing cell-cycle phase distribution in colorectal resection specimens would enable phase data to be incorporated into diagnostic algorithms for the estimation of prognosis and response to adjuvant chemotherapy in colorectal cancer. In contrast to flow cytometry, an immunohistochemical method would also allow the phase distribution to be examined within morphologically heterogeneous regions of neoplasms. Paraffin sections of normal colon (n = 25), colonic adenoma (n = 15), and colonic adenocarcinoma (n = 30) were analysed by immunohistochemistry using antibodies against markers of cell-cycle entry, Mcm-2 and Ki67, and putative markers of the cell-cycle phase, cyclins D1 and E (putative markers of G1 phase), cyclin A (S phase), cytoplasmic cyclin B1 (G2 phase), and phosphohistone H3 (M phase). The phase specificity of each marker was assessed by examining the degree of co-expression of adjacent phase markers using double-antibody fluorescence confocal microscopy and by comparison with flow cytometric analysis performed on adjacent tissue sections. The S-phase specificity of detectable cyclin A was also assessed in combination with in situ DNA replication using fluorescence confocal microscopy. All cells expressing phase markers co-expressed Mcm-2. Adjacent phase markers were not significantly co-expressed, confirming the relative specificity of these markers in tissue sections of colon. Cell-cycle phase distribution, calculated by immunohistochemistry, compared well with phase analyses obtained by flow cytometry. No cells expressed cyclin A in the absence of active DNA replication. The S-phase labelling index, as defined by detectable cyclin A expression, showed a positive correlation with the Mcm-2 labelling index and increased in the progression from normal colon to adenocarcinoma. In conclusion, a combination of these cell-cycle phase markers can be used to calculate the distribution of cells throughout each phase of the cell cycle in colorectal tissue sections. Detectable cyclin A can be used as a surrogate marker of S phase and may be of value in predicting prognosis and response to adjuvant therapy.  相似文献   
107.
The expression of reelin, a large extracellular matrix glycoprotein, was studied in the brain of pre-spawning adult sea lampreys by immunohistochemistry using two monoclonal antibodies against this protein. Reelin immunoreactive (reln-ir) neurons were observed in the olfactory bulb, and pallial and subpallial regions in the telencephalon. In the diencephalon, reln-ir cells were observed in some hypothalamic nuclei, in the nucleus of Bellonci, and in the habenula. In the mesencephalon, this protein was detected in several nuclei related with the centrifugal visual system, although the optic tectum was devoid of immunoreactivity. The hindbrain showed several nuclei with immunopositive neurons, including the branchiomeric nerve motor nuclei and also some groups of non-giant cells of the reticular formation. The rostral spinal cord showed some immunopositive neurons mainly located in lateral and ventral positions. Overall, the pattern of distribution of reelin in the adult sea lamprey correlates with the previously reported in other adult vertebrates. Furthermore, the wide distribution of reelin in the adult lamprey brain is consistent with a possible existence of different roles for this protein not related with development in the central nervous system (CNS) of vertebrates (i.e. neuronal plasticity and/or maintenance).  相似文献   
108.
The aim of this study is to examine relationships of sleep duration with sociodemographic and health‐related factors, psychiatric disorders and sleep disturbances in a nationwide sample in Korea. A total of 6510 subjects aged 18–64 years participated in this study. Logistic regression was used to calculate the odd ratios and 95% confidence intervals of the covariates, psychiatric disorders and sleep disturbances across the following sleep duration categories: 5 h or less, 6, 7, 8 and 9 h or more per day. Low levels of education, unemployment and physical illness were associated with sleeping for 5 h or less and 9 h or more. Being older and widowed/divorced/separated, high levels of physical activity, pain/discomfort, obesity and high scores on the General Health Questionnaires were associated with sleeping for 5 h or less. Female, being younger and underweight were associated with sleeping for 9 h or more. Alcohol dependence, anxiety disorder and social phobia were associated significantly with sleeping for 5 h or less and 9 h or more. Other psychiatric disorders were more common in subjects who slept for 5 h or less (e.g. alcohol use disorder, mood disorder, major depressive disorder, dysthymic disorder, obsessive‐compulsive disorder and specific phobia) or 9 h or more (e.g. post‐traumatic stress disorder). In addition, subjects who slept for 5 h or less reported more sleep disturbances than did subjects who slept for 7 h. Short or long sleep is associated with psychiatric disorders and/or sleep disturbance, therefore attention to the mental health of short or long sleepers is needed.  相似文献   
109.
卵巢恶性肿瘤是女性生殖系统常见的恶性肿瘤之一,中国人群卵巢癌新发病例为52100例/年,死亡达22500例/年[1].由于缺乏有效的早期筛查手段,患者就诊时多为晚期,中国卵巢癌患者5年生存率约为40%[2].近年来,随着抗血管生成药物、聚腺苷二磷酸核糖聚合酶(poly ADP-ribose polymerase,PAR...  相似文献   
110.
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