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71.
A combination of laboratory and field investigations of birds has shown that expression of behavior such as territorial aggression can occur throughout the year in many species and in different life history stages. Although it is well known that testosterone regulates territorial aggression in males during the breeding season, the correlation of plasma testosterone and aggression appears to be limited to periods of social instability when a male is challenged for his territory by another male, or when mate-guarding a sexually receptive female. How essentially identical aggression is modulated in non-breeding life history stages is not fully resolved, but despite low circulating levels of testosterone outside the breeding season, expression of territorial aggression does appear to be dependent upon aromatization of testosterone and an estrogen receptor-mediated mechanism. There is accumulating evidence that prolonged high levels of circulating testosterone may incur costs that may potentially reduce lifetime fitness. These include interference with paternal care, exposure to predators, increased risk of injury, loss of fat stores and possibly impaired immune system function and oncogenic effects. We propose six hypotheses to explain how these costs of high testosterone levels in blood may be avoided. These hypotheses are testable and may reveal many mechanisms resulting from selection to avoid the costs of testosterone. It should also be noted that the hypotheses are applicable to vertebrates in general, and may also be relevant for other hormones that have a highly specialized suite of actions in one life history stage (such as breeding), but also have a limited action in other life history stages when the full spectrum of effects would be inappropriate. 相似文献
72.
Yamashita S Nishimaki H Lin ZB Imai H Kumagai K Shindo M Isobe Y Soma K Ohara K Owada T 《The Journal of trauma》2001,51(3):587-590
73.
CASE REPORT: A suicide attempt by a 23-year-old woman involved ingestion of 1000 mL of petroleum naphtha. Early chemical pneumonitis was complicated by life-threatening, diffuse interstitial lung consolidation with pneumatoceles. Pulse steroid therapy beginning on day 17 was associated with remarkable resolution of interstitial consolidation, although an enlarging secondarily infected pneumatocele ruptured to produce a bronchopleural fistula. Thoracic surgery and antibiotic therapy resulted in improvement of the patient's respiratory condition, and she was discharged with no residual respiratory symptoms. High-dose corticosteroid therapy appears to be a useful addition to aggressive supportive treatment in late adult respiratory distress syndrome following hydrocarbon ingestion. 相似文献
74.
Soma Datta 《Ageing international》1993,20(2):55-59
How much do users of long-term care in Canada, the United Kingdom and Sweden pay for those services? 相似文献
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77.
Oxidative stress and inflammatory cytokines such as monocyte chemoattractant protein 1 (MCP-1), TGF-beta, and IL-2 are supposed to play crucial roles in the pathogenesis of insulin resistance (IR). Tranilast is an anti-allergic drug which exerts anti-inflammatory and anti-angiogenesis effects through inhibition of expression of MCP-1, TGF-beta, and antigen-induced IL-2 lymphocyte responsiveness. It also possesses a certain antioxidant activity. Considering the above facts and in view of its safety, tranilast may prove invaluable in the treatment of IR. 相似文献
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79.
The present study was conducted on captive male song sparrows (Melospiza melodia) during the nonbreeding season in order to (1) examine Fos and Zenk responses of basal forebrain sites to simulated territorial intrusion and (2) determine how those responses relate to aggression. Numerous forebrain areas showed significant Fos and Zenk responses to simulated territorial intrusion, and in several areas of the hypothalamus and lateral septum, these responses were negatively correlated with aggressive behavior. Homologous areas in mammals show greater responses in subordinate subjects than in dominant subjects. Thus, these brain areas may be responsive to social stressors across a wide range of vertebrates. 相似文献
80.
The purpose of this qualitative study is to investigate how South and East Asian immigrant women who have diagnoses of serious mental illness make treatment choices in relation to spirituality and to explore how gender, cultural beliefs, and spirituality intersect with the process of choice. The findings reveal that the process of spiritual choice includes three interrelated phases: (1) identifying contributing factors, (2) exploring spiritual resources and strategies, and (3) living with the choices. Variations among health beliefs and health care decisions are explained and services that women see as being helpful are identified. 相似文献