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991.
BACKGROUND: Mitral valve repair (MVR) has been shown to achieve good long-term results. However, this procedure is associated with relevant immediate postoperative mortality. The aim of this study is to identify those preoperative variables associated with an increased risk of 30-d postoperative death. METHODS: One hundred and sixty-four patients underwent MVR at our institution from January 1993 to December 2000. RESULTS: Eleven patients (6.7%) died during the immediate postoperative outcome, a median of 14 d after surgery (range, 1-29 d). One patient (1.3%) out of 80 who underwent MVR as lone procedure died on postoperative day 14 of cardiac tamponade. The mortality rate in those who underwent MVR associated with other procedures was 11.9%. Multivariable analysis (154 patients included in the analysis) showed that patients' age (p = 0.006, for an increase of 10 units: OR 4.33, 95% CI 1.53-12.27), history of prior cardiac surgery (p = 0.006, OR 118.56, 95% CI 4.03-3491.14) and NYHA functional class (p = 0.011, OR 5.66, 95% CI 1.49-21.49) were significantly associated with an increased risk of postoperative death. The receiver operating characteristics (ROC) curve showed that patients' age had an area under the curve of 0.762 (95% CI 0.622-0.901, p = 0.004), its best cut-off value being 65 years (mortality, 13.4% vs 2.1%, p = 0.008, sensitivity 81.8%, specificity 62.1%, accuracy 63.4%). None of the patients older than 65 and with a history of prior cardiac surgery survived the operation. CONCLUSIONS: MVR is associated with a relevant 30-d mortality risk in patients older than 65 years, with advanced NYHA functional class and a history of prior cardiac surgery.  相似文献   
992.
Occupational diseases Nos. 2108 and 2110 correspond to intervertebral disc-related diseases of the lumbar spine from many years of carrying or lifting heavy loads, occupations in extreme postures of full flexion or oscillation of the whole body when seated, and which compel the cessation of all activities which are or could be the cause for the origin, exacerbation or recurrence of the disease. These occupational diseases came into force at the start of 1993, but there have been considerable problems in their implementation. The present Part I of the contribution is the result of the work of an interdisciplinary study group and contains medical criteria for the assessment of possibly strain-related clinical characteristics and the evaluation of other possible causes. Part II is to be published in Volume 4/2005 and will deal with questions related to forced cessation and to the assessment of the loss of earning ability. Agreement was reached in many areas related to the assessment of occupational claims. This should allow for evidence-based decision making in the future for the occupational diseases Nos. 2108 and 2110.  相似文献   
993.
The first part of this serial paper dealt with the medical criteria used in evaluation of the clinical picture caused by physical stress and the evaluation of other candidate causes and was published in issue no. 3/2005 (pp. 711–752) of Trauma and Berufskrankheit. This follow-up paper (II) presents criteria to be used in the evaluation of whether it is necessary to give up the occupations putting the spine at risk and in estimation of the degree of disability.  相似文献   
994.
Objectives: Previous studies have been inconsistent with regard to the extent to which stress perception, rather than stressor exposure, predicts negative health symptoms. Because sex differences have been observed in all three of these variables, in this study the possibility that sex differences also exist in the relationships between them is investigated. Methods: Self‐report inventories of perceived stress, stressor exposure, and negative health symptoms were given to 107 young‐adult participants (65 females, 42 males). Results: Sex differences were observed in the associations among perceived stress, stressor exposure, and negative health symptom rates. Specifically, while higher perceived stress and higher stressor exposure rates independently predicted higher negative health symptoms rates in females, only higher stressor exposure rates independently predicted higher negative health symptoms in males. Indeed, unexpectedly, after controlling for exposure to stressors there was a trend towards higher perceived stress predicting lower negative health symptoms in males. Conclusions: While exposure to stress was a significant negative predictor of health for both sexes, perception of stress was predictive only for females. One implication of this finding is that different psychological models are needed to predict health symptoms in the two sexes. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
995.
996.
Sherry NA  Tsai EB  Herold KC 《Diabetes》2005,54(Z2):S32-S39
Despite extensive and ongoing investigations of the immune mechanisms of autoimmune diabetes in humans and animal models, there is much less information about the natural history of insulin secretion before and after the clinical presentation of type 1 diabetes and the factors that may affect its course. Studies of insulin production previously published and from the Diabetes Prevention Trial (DPT)-1 suggest that there is progressive impairment in insulin secretory responses but the reserve in response to physiological stimuli may be significant at the time of diagnosis, although maximal responses are more significantly impaired. Other factors, including insulin resistance, may play a role in the timing of clinical presentation along this continuum. The factors that predict the occurrence and rapidity of decline in beta-cell function are still largely unknown, but most studies have identified islet cell autoantibodies as predictors of future decline and age as a determinant of residual insulin production at diagnosis. Historical as well as recent clinical experience has emphasized the importance of residual insulin production for glycemic control and prevention of end-organ complications. Understanding the modifiers and predictors of beta-cell function would allow targeting immunological approaches to those individuals most likely to benefit from therapy.  相似文献   
997.
The traditional view that organs have only limited regenerative capacity has been challenged in recent years as adult bone marrow stem cells as well circulating progenitor cells have been identified to retain the plasticity to participate in neovascularization, a process so far believed not to be possible after birth. An organ that is damaged by ischemia causes the release of cytokines; these act via the flowing blood and stimulate the bone marrow, which then mobilizes progenitor cells to the blood and directs them to adhere to and migrate into the damaged organ. Thus, these progenitor cells most likely constitute a natural repair mechanism that counteracts degenerative or aging processes. On the basis of encouraging experimental data, first clinical trials have been established to demonstrate the safety and the feasibility of progenitor cell therapy in case of peripheral artery disease or myocardial infarction. Trials investigating injection of bone marrow or circulating progenitor cells into the coronary artery after an acute myocardial infarction not only demonstrates safety of the procedure but also gave hints toward efficacy. Nevertheless, these findings have to be validated by subsequent larger, prospective, randomized, controlled trials. There are also potential topics in nephrology, where modification of progenitor cell activity might be of benefit, such as renal ischemic disease, glomerular disease, and renal transplant vasculopathy. Finding a way to integrate the principle of progenitor cell action into therapeutic efforts might provide a completely new therapeutic strategy that not only attempts to retard disease progression but furthermore targets to regenerate damaged organs.  相似文献   
998.

Background/Purpose

Intestinal adaptation is a compensatory response to massive small bowel loss in which there are increased numbers of absorptive enterocytes. However, the generation of secretory epithelial cell subtypes in this process has not been investigated. The purpose of this study was to examine the adaptive changes of several small intestinal cell lineage changes in response to massive small bowel resection (SBR).

Methods

A 75% SBR or sham operation was performed on male Sprague-Dawley rats. On postoperative day 7, the remnant ileum was harvested and immunohistochemical staining for goblet, Paneth, and enteroendocrine cells was performed. Cell subtypes were evaluated as cells per micrometer of villus/crypt length and compared among operations.

Results

A significant increase in goblet cell density occurred after SBR. Intestinal resection did not alter the number of Paneth and enteroendocrine cells. In additional experiments, inhibition of epidermal growth factor receptor signaling was associated with a diminished goblet cell density.

Conclusions

The adaptive response of the intestine to massive bowel loss results in an expansion of the goblet cell population in addition to greater numbers of absorptive enterocytes. Although the mechanism and purpose for selective expansion of these stem cell-derived lineages are not presently known, epidermal growth factor receptor signaling appears to be a common pathway.  相似文献   
999.
1000.
Hepatobiliary cystadenomas and cystadenocarcinomas are rare tumors. Differentiating between these tumors and benign hepatic cysts may be difficult. Because of their rarity, diagnosis is often delayed and may result in inaccurate treatment, resulting in unnecessary morbidity and mortality. The purpose of this report is to draw attention to these entities and their complications. We report on two cases with spontaneous rupture of hepatobiliary cystadenoma and cystadenocarcinoma cysts, initially treated as simple hepatic cysts by aspiration, or by aspiration combined with sclerotherapy. The spontaneous rupture of the cysts appeared years after the initial treatment of the cysts, leading in one case to a prolonged stay in an intensive care unit. In both cases, a formal liver resection was carried out and microscopic investigations revealed a mucinous cystadenocarcinoma and cystadenoma. In conclusion, although hepatobiliary cystadenomas and cystadenocarcinomas are rare findings, they should not be forgotten in the diagnostic workshop when examining patients with hepatic cysts. If hepatobiliary cystadenomas and cystadenocarcinomas cannot be excluded following radiological imaging, surgery is recommended.  相似文献   
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