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1.
Hip fractures among elderly people frequently result in permanent disabilities, nursing home placement, and death. The bulk of hip fracture research focuses on elderly women. Within the Veterans Health Administration (VHA), the majority of patients are men. There are no published national reports on hip fractures with large male samples, or on related inpatient mortality among veterans. This retrospective study of 13,546 veterans with hip fracture discharges from 1998-2002 found unadjusted mortality rates are higher in the VHA, compared with the general population. VHA patients tend to be older men in poor health who stay in the hospital longer Increased knowledge about the risks and outcomes associated with hip fractures in men could lead to improved primary and secondary injury-prevention programs. Rehabilitation nurses in acute care can be catalysts in proactively incorporating protective devices, screening for osteoporosis, and initiating lifestyle changes in their plans of care to optimize outcomes for hip fracture patients.  相似文献   
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The aim of this cross-sectional study was to estimate the prevalence of different subtypes of idiopathic focal dystonia in the population of Belgrade (Serbia), Yugoslavia. On December 31, 2001, the crude prevalence of all studied types of dystonia (focal, segmental, and multifocal) in Belgrade was 13.6 per 100,000 population (11.8 per 100,000 for men and 15.2 per 100,000 for women). Type-specific prevalence for focal dystonia was 11.2 per 100,000. The prevalence for cervical dystonia, blepharospasm, writer's cramp and laryngeal dystonia were 5.9 per 100,000, 1.9 per 100,000, 1.9 per 100,000, and 1.1 per 100,000, respectively.  相似文献   
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Orbicularis oculi (eye blink) electromyogram, skin conductance, and heart rate responses to 15 consecutive 95-dB, 500-millisecond, 1000-Hz tones with 0-millisecond rise and fall times were measured in 14 patients with posttraumatic stress disorder, 14 patients with other anxiety disorders, 15 mentally healthy subjects with past traumatic experiences, and 19 mentally healthy subjects with no trauma history. The patients with posttraumatic stress disorder showed significantly larger skin conductance and heart rate responses and a trend toward larger electromyogram responses to the tones than every other group. These effects were not explained by subjective anxiety, resting physiologic arousal, physiologic arousal preceding the tone trials, or initial physiologic responsivity. The group with posttraumatic stress disorder was the only one that failed to show habituation of skin conductance responses.  相似文献   
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Aim: Fas membrane-associated polypeptide antigen is a receptor molecule responsible for apoptosis-mediated signals. In animal models of acute viral hepatitis, apoptosis of hepatocytes is mediated by Fas-death receptors; therefore, the aim of this study was to evaluate the effect of interferon (IFN)-alpha on apoptotic markers and nuclease activity against different coding and non-coding single and double stranded RNAs during Fas-induced liver apoptosis. Methods: An in vivo experiment was performed with simultaneous administration of anti-Fas (CD95) antibodies and IFN-alpha, and an in vitro experiment was performed in hepatocyte cultures treated with anti-Fas antibodies and IFN-alpha. Results: Detection of apoptosis using Annexin V-FITC/propidium iodide, Bcl-2 and Bax expression in hepatocyte cultures confirmed the appearance of early apoptotic events and progression toward late apoptosis after anti-Fas antibody treatment. IFN-alpha had a tendency to retard the apoptosis process in Fas-induced apoptosis by increasing the number of viable cells and decreasing the number of cells in late apoptosis, by increasing the percentage of Bcl-2 positive cells, by decreasing the percentage of Bax positive cells, and by decreasing the nuclease activity compared to the anti-Fas antibody treated group. Total DNA and RNA concentration was much reduced in the Fas group and DNA fragmentation assay provided evidence for increased DNA degradation. Enhanced nuclease activity against DNA, rRNA, poly(A), poly(C), poly(U), poly(I:C), and poly(A:U) was manifested in the anti-Fas antibody treated group, except for the inhibitory-bound alkaline RNase. Conclusions: The results demonstrate that the RNA-degrading pathway in Fas-induced apoptosis can accelerate the liberation of the latent enzyme from the inhibitor complex. IFN-alpha prevented enormous, Fas-ligand induced degradation of all the substrates used in this experimental study, most probably due to similarities in the signal transduction pathways. Investigations of death receptor-induced apoptosis may lead to novel treatment combinations for patients with acute or chronic liver diseases.  相似文献   
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In order to investigate the DA activity in polycystic ovary syndrome (PCOS) we studied the response of LH, FSH and PRL to a dopamine receptor antagonist metoclopramide (MCP-10 mg iv) in 12 PCO subjects (7 with normal and 5 with elevated levels of prolactin). The prolactin and LH responses to metoclopramide were compared to those obtained in 6 normal cycling women. Although a significant increase in PRL levels was documented after MCP administration in all PCO patients and normal cycling women (p less than 0.01), the highest increment in PRL levels was observed in normoprolactinemic PCO subjects. In contrast a blunted PRL response was observed in hyperprolactinemic PCO patients. There was a negative correlation between basal PRL levels and the maximum net increase in PRL after MCP. In both groups of PCO subjects MCP administration caused initial decrease in LH levels followed by an increase after 4 h. In hyperprolactinemic PCO patients this observed MCP effect on LH was more pronounced and significantly different in comparison with normoprolactinemic PCO patients (p less than 0.01). MCP administration did not cause significant acute alterations in LH levels in normal cycling women and no significant FSH changes in either PCO or control subjects. A relative dopamine deficiency might cause hypersecretion of PRL and LH in patients with PCOS and hyperprolactinemia.  相似文献   
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The effects of adrenalectomy, gonadectomy and combined adrenalectomy plus gonadectomy on the previously described sex-dependent anticonvulsive effect of swim stress were studied in rats. The convulsive signs (myoclonic twitch, generalized convulsions, tonic hindlimb extension) were produced by constant i.v. infusion of γ-aminobutyric acidA (GABAA) antagonist bicuculline, which started 15 min after termination of swim stress (10-min swim at 18–19°C). Adrenalectomy decreased the threshold doses of bicuculline producing the first myoclonic twitch and the onset of generalized convulsions only in females. In adrenalectomized females, but not in males, swim stress enhanced the threshold dose of bicuculline producing generalized convulsions, but, unlike in adrenal-intact animals, it failed to enhance the dose of bicuculline producing tonic hindlimb extension. In gonadectomized stressed and unstressed animals all sex differences disappeared, and swim stress enhanced in both sexes only the threshold doses of bicuculline producing tonic hindlimb extension. Adrenalectomized plus gonadectomized animals displayed clear sex differences in doses of bicuculline necessary to produce all the convulsive signs. In the same animals swim stress postponed, especially in females, the onset of the first myoclonic twitch and generalized convulsions, but not the onset of tonic hindlimb extension. In summary, our results suggest that hormones of the adrenal and gonadal glands are only partly responsible for decreased susceptibility, especially of female rats, to the GABAA antagonist bicuculline. Moreover, they have demonstrated that stress produces a gender-specific anticonvulsive effect even in the animals completely deprived of steroid hormones of peripheral origin. Received: 4 June 1998 / Accepted: 11 June 1999  相似文献   
10.
Two-component systems are widely distributed in prokaryotes where they control gene expression in response to diverse stimuli. To study the role of the sixteen putative two-component systems of Listeria monocytogenes systematically, in frame deletions were introduced into 15 out of the 16 response regulator genes and the resulting mutants were characterized. With one exception the deletion of the individual response regulator genes has only minor effects on in vitro and in vivo growth of the bacteria. The mutant carrying a deletion in the ortholog of the Bacillus subtilis response regulator gene degU showed a clearly reduced virulence in mice, indicating that DegU is involved in the regulation of virulence-associated genes.  相似文献   
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