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161.
党凯  高云芳 《动物学杂志》2016,51(3):497-506
非冬眠动物的骨骼肌在废用条件下会发生明显的萎缩。冬眠动物在历经数月的冬眠期骨骼肌废用后,仍能保持较完整的形态结构与良好的收缩功能,成为天然的抗废用性肌萎缩动物模型。探明冬眠动物骨骼肌对废用的生理适应机制,是生理生态学领域的重要课题之一。本文从形态结构、肌纤维类型和收缩功能等方面综述了冬眠动物对冬眠期骨骼肌废用状态的生理适应,并从蛋白质代谢、生长与分化的调控、代谢类型的调控、氧化应激以及线粒体结构与氧化能力等方面分析了冬眠期骨骼肌生理适应的可能机制。  相似文献   
162.
Effective management of infectious disease relies upon understanding mechanisms of pathogen transmission. In particular, while models of disease dynamics usually assume transmission through direct contact, transmission through environmental contamination can cause different dynamics. We used Global Positioning System (GPS) collars and proximity‐sensing contact‐collars to explore opportunities for transmission of Mycobacterium bovis [causal agent of bovine tuberculosis] between cattle and badgers (Meles meles). Cattle pasture was badgers’ most preferred habitat. Nevertheless, although collared cattle spent 2914 collar‐nights in the home ranges of contact‐collared badgers, and 5380 collar‐nights in the home ranges of GPS‐collared badgers, we detected no direct contacts between the two species. Simultaneous GPS‐tracking revealed that badgers preferred land > 50 m from cattle. Very infrequent direct contact indicates that badger‐to‐cattle and cattle‐to‐badger M. bovis transmission may typically occur through contamination of the two species’ shared environment. This information should help to inform tuberculosis control by guiding both modelling and farm management.  相似文献   
163.
Since the early 1990s, the term “genetic discrimination” has been used to designate adverse treatment on the grounds of genetic makeup. However, the full spectrum of possible disadvantage associated with genetic information has not been addressed by either the international scientific debate or statutory arrangements on genetic discrimination. Informed by legal contexts, they almost all focus on one specific group: the “asymptomatic ill.” On the basis of the sociological study, “Genetic Discrimination in Germany,” this article proposes to revise the terms of the debate and discusses some limitations of the concept. Drawing on the experiences reported by affected individuals, it advocates a more expansive social understanding which does not require that a person has to be healthy to be at risk of genetic discrimination.  相似文献   
164.
The effects of increased temperature were tested in Amphiprion ocellaris, using a cellular diagnostics approach (in several tissues) combined with an organismal approach (body condition). Clownfish were exposed to a one month experiment following two temperature treatments: control (26 °C) and elevated temperature (30 °C). Fish were sampled at 0, 7, 14, 21 and 28 days for (1) assessment of stress biomarkers (catalase, lipid peroxidation, glutathione-S-transferase, superoxide dismutase, acetylcholinesterase, heat shock protein 70 kDa and ubiquitin – in brain, gills, liver, intestine and muscle), (2) estimation of integrated biomarker response index based on the biomarkers tested and (3) assessment of Fulton’s K index. Results show all biomarkers except acetylcholinesterase responded consistently and significantly to elevated temperature across tissue types suggesting they are suitable indicators of thermal stress in A. ocellaris. Biomarker levels were tissue-specific, and in addition, the most reactive tissues to temperature were muscle, gills and liver which suggest that highly oxygenated tissues seem to be the most responsive under thermal stress. The most responsive sampling times to increased temperature were T7 and T28: thermal stress was observed after 7 days of exposure (biomarker levels increased), then a pattern of decrease in biomarker levels towards the end of the experiment was observed, which may suggest fish were able to acclimate to exposure conditions. This indicates that A. ocellaris probably lives far from its upper thermal limit and is capable of adjusting the protein quality control system and enzymes’ activities to protect cell functions under elevated temperatures. The temperature treatment did not significantly influence body condition of the animals but biomarkers were negatively correlated to wet body weight. This suggests that thermal acclimation incurs at some energetic cost. In conclusion, these results suggest that this coral reef fish species presents a significant acclimation potential under ocean warming scenarios of +4 °C.  相似文献   
165.
The objective of this study was to detail the nature and correlates of mental health and non‐mental health care contacts prior to suicide death. We conducted a systematic extraction of data from records at the Office of the Chief Coroner of Ontario of each person who died by suicide in the city of Toronto from 1998 to 2011. Data on 2,835 suicide deaths were linked with provincial health administrative data to identify health care contacts during the 12 months prior to suicide. Sub‐populations of suicide decedents based on the presence and type of mental health care contact were described and compared across socio‐demographic, clinical and suicide‐specific variables. Time periods from last mental health contact to date of death were calculated and a Cox proportional hazards model examined covariates. Among suicide decedents, 91.7% had some type of past‐year health care contact prior to death, 66.4% had a mental health care contact, and 25.3% had only non‐mental health contacts. The most common type of mental health contact was an outpatient primary care visit (54.0%), followed by an outpatient psychiatric visit (39.8%), an emergency department visit (31.1%), and a psychiatric hospitalization (21.0%). The median time from last mental health contact to death was 18 days (interquartile range 5‐63). Mental health contact was significantly associated with female gender, age 25‐64, absence of a psychosocial stressor, diagnosis of schizophrenia or bipolar disorder, past suicide attempt, self‐poisoning method and absence of a suicide note. Significant differences between sub‐populations of suicide decedents based on the presence and nature of their health care contacts suggest the need for targeting of community and clinical‐based suicide prevention strategies. The predominance of ambulatory mental health care contacts, often close to the time of death, reinforce the importance of concentrating efforts on embedding risk assessment and care pathways into all routine primary and specialty clinical care, and not only acute care settings.  相似文献   
166.
In the World Health Organization's forthcoming eleventh revision of the International Classification of Diseases and Related Health Problems (ICD‐11), substantial changes have been proposed to the ICD‐10 classification of mental and behavioural disorders related to sexuality and gender identity. These concern the following ICD‐10 disorder groupings: F52 Sexual dysfunctions, not caused by organic disorder or disease; F64 Gender identity disorders; F65 Disorders of sexual preference; and F66 Psychological and behavioural disorders associated with sexual development and orientation. Changes have been proposed based on advances in research and clinical practice, and major shifts in social attitudes and in relevant policies, laws, and human rights standards. This paper describes the main recommended changes, the rationale and evidence considered, and important differences from the DSM‐5. An integrated classification of sexual dysfunctions has been proposed for a new chapter on Conditions Related to Sexual Health, overcoming the mind/body separation that is inherent in ICD‐10. Gender identity disorders in ICD‐10 have been reconceptualized as Gender incongruence, and also proposed to be moved to the new chapter on sexual health. The proposed classification of Paraphilic disorders distinguishes between conditions that are relevant to public health and clinical psychopathology and those that merely reflect private behaviour. ICD‐10 categories related to sexual orientation have been recommended for deletion from the ICD‐11.  相似文献   
167.
This paper aims to give an overview of the key issues facing those who are in a position to influence the planning and provision of mental health systems, and who need to address questions of which staff, services and sectors to invest in, and for which patients. The paper considers in turn: a) definitions of community mental health care; b) a conceptual framework to use when evaluating the need for hospital and community mental health care; c) the potential for wider platforms, outside the health service, for mental health improvement, including schools and the workplace; d) data on how far community mental health services have been developed across different regions of the world; e) the need to develop in more detail models of community mental health services for low‐ and middle‐income countries which are directly based upon evidence for those countries; f) how to incorporate mental health practice within integrated models to identify and treat people with comorbid long‐term conditions; g) possible adverse effects of deinstitutionalization. We then present a series of ten recommendations for the future strengthening of health systems to support and treat people with mental illness.  相似文献   
168.
The experience of burnout has been the focus of much research during the past few decades. Measures have been developed, as have various theoretical models, and research studies from many countries have contributed to a better understanding of the causes and consequences of this occupationally‐specific dysphoria. The majority of this work has focused on human service occupations, and particularly health care. Research on the burnout experience for psychiatrists mirrors much of the broader literature, in terms of both sources and outcomes of burnout. But it has also identified some of the unique stressors that mental health professionals face when they are dealing with especially difficult or violent clients. Current issues of particular relevance for psychiatry include the links between burnout and mental illness, the attempts to redefine burnout as simply exhaustion, and the relative dearth of evaluative research on potential interventions to treat and/or prevent burnout. Given that the treatment goal for burnout is usually to enable people to return to their job, and to be successful in their work, psychiatry could make an important contribution by identifying the treatment strategies that would be most effective in achieving that goal.  相似文献   
169.
Mathematical approaches made for both the charged dislocation model and piezoelectrically induced electron bombardment model of fracto‐mechanoluminescence (FML), the luminescence induced by fracture of solids, in ZnS:Mn phosphor indicate that the piezoelectrically induced electron bombardment model provides a dominating process for the FML of ZnS phosphors. The concentration of 3000 ppm Mn2+ is optimal for ML intensity of ZnS:Mn phosphor. The decay time of ML gives the relaxation time of the piston used to deform the sample and the time tm of maximum of ML is controlled by both the relaxation time of the piston and decay time of charges on the newly created surfaces of crystals. As the product of the velocity of dislocations and pinning time of dislocations gives the mean free path of a moving dislocation. Both factors play an important role in the ML excitation of impurity doped II–VI semiconductors. The linear increase of total ML intensity IT with the impact velocity indicates that the damage increases linearly with impact velocity of the load. Thus, the ML measurement can be used remotely to monitor the real‐time damage in the structures, and therefore, the ML of ZnS:Mn phosphor has also the potential for a structural health monitoring system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
170.
p27Kip1 was first discovered as a key regulator of cell proliferation. The canonical function of p27Kip1 is inhibition of cyclin-dependent kinase (CDK) activity. In addition to its initial identification as a CDK inhibitor, p27Kip1 has also emerged as an intrinsically unstructured, multifunctional protein with numerous non-canonical, CDK-independent functions that exert influence on key processes such as cell cycle regulation, cytoskeletal dynamics and cellular plasticity, cell migration, and stem-cell proliferation and differentiation. Many of these non-canonical functions, depending on the cell-specific contexts such as oncogenic activation of signaling pathways, have the ability to turn pro-oncogenic in nature and even contribute to tumor-aggressiveness and metastasis. This review discusses the various non-canonical, CDK-independent mechanisms by which p27Kip1 functions either as a tumor-suppressor or tumor-promoter.  相似文献   
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