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31.
Antidepressants are used for long periods of time and until recently there were no formal requirements for establishing efficacy in the maintenance phase or the prophylactic phase of the treatment of depression. The CPMP guidelines advise regulatory authorities in the EEC to consider the efficacy of antidepressants in the medium and the long term separately from efficacy in the treatment of the acute episode. This paper reviews the efficacy of antidepressants in continuation treatment and prophylactic treatment of unipolar depression. Prophylactic studies are difficult and time consuming and it is important to adopt adequate trial methodology. The minimum criteria for the demonstration of prophylactic efficacy are presented.  相似文献   
32.

Background

Intimate partner violence (IPV) against women is a global public health problem, yet data on IPV against Native American women are extremely limited. We conducted a cross-sectional study of Native American women to determine prevalence of lifetime and past-year IPV and partner injury; examine IPV in relation to pregnancy; and assess demographic and socioeconomic correlates of past-year IPV.

Methods

Participants were recruited from a tribally-operated clinic serving low-income pregnant and childbearing women in southwest Oklahoma. A self-administered survey was completed by 312 Native American women (96% response rate) attending the clinic from June through August 1997. Lifetime and past-year IPV were measured using modified 18-item Conflict Tactics Scales. A socioeconomic index was created based on partner's education, public assistance receipt, and poverty level.

Results

More than half (58.7%) of participants reported lifetime physical and/or sexual IPV; 39.1% experienced severe physical IPV; 12.2% reported partner-forced sexual activity; and 40.1% reported lifetime partner-perpetrated injuries. A total of 273 women had a spouse or boyfriend during the previous 12 months (although all participants were Native American, 59.0% of partners were non-Native). Among these women, past-year prevalence was 30.1% for physical and/or sexual IPV; 15.8% for severe physical IPV; 3.3% for forced partner-perpetrated sexual activity; and 16.4% for intimate partner injury. Reported IPV prevalence during pregnancy was 9.3%. Pregnancy was not associated with past-year IPV (odds ratio = 0.9). Past-year IPV prevalence was 42.8% among women scoring low on the socioeconomic index, compared with 10.1% among the reference group. After adjusting for age, relationship status, and household size, low socioeconomic index remained strongly associated with past-year IPV (odds ratio = 5.0; 95% confidence interval: 2.4, 10.7).

Conclusions

Native American women in our sample experienced exceptionally high rates of lifetime and past-year IPV. Additionally, within this low-income sample, there was strong evidence of socioeconomic variability in IPV. Further research should determine prevalence of IPV against Native American women from diverse tribes and regions, and examine pathways through which socioeconomic disadvantage may increase their IPV risk.
  相似文献   
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We have shown that a murine CD4+ PPD-reactive T lymphocyte clone was weakly cytotoxic towards the syngeneic tumour B16 melanoma and MC6A fibrosarcoma which had been coated with PPD using a monoclonal antibody-PPD heteroconjugate. Cell-free supernatants produced by PPD-stimulated T lymphocyte clones were however highly cytostatic for the two tumour targets when assayed over 48-72 h. In this study we have demonstrated good titres of tumour necrosis factor (TNF) and interferon-gamma (IFN-gamma) in the supernatants, which accounted for their observed cytostatic activity on the tumour targets. The high level of cytostasis seen with the B16 melanoma using the supernatants could be attributed to their sensitivity to the cytostatic activity of IFN-gamma; the lower levels of cytostasis seen with the IFN-gamma-resistant MC6A target was the result of IFN-gamma increasing the sensitivity of this target to TNF. Antibodies to IFN-gamma were able to neutralize the majority of the cytostatic activity of the supernatants on both targets, consistent with the role demonstrated for this lymphokine.  相似文献   
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Life expectancy in British Marfan syndrome populations   总被引:2,自引:0,他引:2  
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome.  相似文献   
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To study the effects of physical conditioning on the hypothalamic-pituitary-adrenal axis, we examined the plasma ACTH, cortisol, and lactate responses in sedentary subjects, moderately trained runners, and highly trained runners to graded levels of treadmill exercise (50, 70, and 90 percent of maximal oxygen uptake) and to intravenous ovine corticotropin-releasing hormone (1 microgram per kilogram of body weight). Basal evening concentrations of ACTH and cortisol, but not of lactate, were elevated in highly trained runners as compared with sedentary subjects and moderately trained runners. Exercise-stimulated ACTH, cortisol, and lactate responses were similar in all groups and were proportional to the exercise intensity employed. These responses, however, were attenuated in the trained subjects when plotted against applied absolute workload. Only the highly trained group had diminished responses of ACTH and cortisol to ovine corticotropin-releasing hormone, consistent with sustained hypercortisolism. We conclude that physical conditioning is associated with a reduction in pituitary-adrenal activation in response to a given workload. Alterations of the hypothalamic-pituitary-adrenal axis consistent with mild hypercortisolism and similar to findings in depression and anorexia nervosa were found only in highly trained runners. Whether these alterations represent an adaptive change to the daily stress of strenuous exercise or a marker of a specific personality profile in highly trained athletes is unknown.  相似文献   
40.
Fatigue is the most common side effect of chemotherapy for cancer. Not yet explored is the possibility that patients may develop conditioned fatigue responses to clinic cues as a result of the repeated pairing of the clinic environment (conditioned stimulus) with infusions of chemotherapy (unconditioned stimulus) that cause fatigue (unconditioned response). As a first critical test of this possibility, breast cancer patients (N = 82) were studied across their first four cycles of chemotherapy. Consistent with conditioning: (1) fatigue levels in the clinic environment significantly increased with repeated pairings of the clinic environment and chemotherapy administration; (2) fatigue responses in the clinic environment prior to the fourth infusion (CR) were predicted by patients’ previous experiences of post-infusion fatigue (UR) above and beyond effects of concurrent emotional distress. These results provide the first evidence in the literature that fatigue can be conditioned. Additional research is warranted to determine the clinical importance of this source of fatigue in chemotherapy patients.  相似文献   
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