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31.
Effects of Ethanol on the Contractile Function of the Heart: A Review   总被引:7,自引:0,他引:7  
Chronic ethanol consumption leads to a number of alterations in the contractile function of the heart and is a leading cause of cardiomyopathy. Ethanol also has an acute negative inotropic effect mediated by direct interaction with cardiac muscle cells, although this action is often masked by indirect actions resulting from enhanced release of catecholamines in vivo. This article reviews the effects of ethanol on the contractile function of the heart. The specific targets affected by ethanol in cardiac muscle cells are discussed in terms of potential mechanisms underlying the depressions of contractility resulting from both acute and chronic actions of ethanol.  相似文献   
32.
Standing posture is made possible by hip extension and lumbar lordosis. Lumbar lordosis is correlated with pelvic parameters, such as the declivity angle of the upper surface of the sacrum and the incidence angle, which determine the sagittal morphotype. Incidence angle, which is different for each individual, is known to be very important for upright posture, but its course during life has not yet been established. Incidence angle was measured on radiographs of 30 fetuses, 30 children and 30 adults, and results were analysed using the correlation coefficientr and Student's t test. A statistically significant correlation between age and incidence angle was observed. Incidence angle considerably increases during the first months, continues to increase during early years, and stabilizes around the age of 10 years. Incidence is a mark of bipedism, and its role in sagittal balance is essential.  相似文献   
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OBJECTIVE: To assess the extent of nosocomial transmission of tuberculosis among infants, family members, and healthcare workers (HCWs) who were exposed to a 29-week-old premature infant with congenital tuberculosis, diagnosed at 102 days of age. DESIGN: A prospective exposure investigation using tuberculin skin test (IST conversion was conducted. Contacts underwent two skin tests 10 to 12 weeks apart. Clinical examination and chest radiographs were performed to rule out disease. Isoniazid prophylaxis was administered to exposed infants at higher risk. SETTING: A neonatal intensive care unit in an urban hospital in Brussels, Belgium. PARTICIPANTS: Ninety-seven infants, 139 HCWs, and 180 visitors. RESULTS: Newly positive TST results occurred in HCWs who had been in close contact with the infant. Six (19%) of 32 primary care nurses and physicians had TST conversions and received treatment. Among the 97 exposed infants, 85 were screened and 34 were identified as at higher risk of infection. Of these, 27 received preventive isoniazid. None of the infants and none of the 93 other infants' family members evaluated were infected. CONCLUSIONS: Congenital tuberculosis in an infant poses a risk for nosocomial transmission to HCWs. Delayed diagnosis of this rare disease and close proximity are the most important factors related to transmission.  相似文献   
35.
A study was performed to determine quantitatively the alterations in phosphorus metabolite concentrations and pH in regions of the human brain damaged by chronic stroke. Image-guided phosphorus-31 magnetic resonance spectroscopy was performed on the brains of eight healthy subjects and six patients with cerebral infarction of more than 3 months duration. Phosphorus metabolite concentrations in infarcted regions were reduced 8%-67%. Significant decreases occurred in phosphomonoester (PME), phosphodiester (PDE), and adenosine triphosphate (ATP) concentrations, while inorganic phosphate (Pi) and phosphocreatine (PCr) concentrations showed smaller, nonsignificant decreases. The PCr/ATP ratio was significantly increased, while the ATP/Pi ratio was somewhat lower. The phospholipid ratio PDE/PME was also significantly increased, while the ratios of phospholipid (PME, PDE) to phosphate (PCR, Pi) metabolites were significantly decreased. The pH of the infarcted region indicated significantly more alkalinity than in the normal brain. The results suggest that chronic stroke is associated with significant changes in brain metabolite concentrations and pH that are different from those reported for other brain diseases.  相似文献   
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Hepatic vascular changes are generally associated to fibrotic lesions of the liver but their role in the development and extension of fibrosis is not well known. By performing a portacaval anastomosis in rats, a proliferation of hepatic vessels was attained progressively, comparable to proliferations seen in cirrhosis and schistosomiasis. Such a modification of the hepatic vasculature was accompanied by changes in the connective matrix of the liver, mainly related to the vascular walls. Moreover, sinusoidal capillarization was detected at the electron microscopical level whereas no alterations could be seen neither in the distribution nor in the quality of the connective matrix proteins with Immunofluorescence technique. The only modification detected by light microscopy, at this zone, was the shrinked aspect of reticulin fibers which could be related to the important liver atrophy provoked by the anastomosis. It can be assumed that in liver pathology, selective changes occur in the connective matrix components depending on the type of injury. Necrotic and inflammatory processes lead mainly to the deposition of interstitial collagens and associated proteins, related to a diffuse stroma reaction resultant from activation of specific cell populations whereas in portacaval anastomosis, a selective increase of vascular connective matrix (mainly basement membrane components) occurs as a direct consequence of vessel proliferation.  相似文献   
38.
The perception of the pain, and the “work of pain” which ensues from it, bound to the notion of trauma-hurt to subjects presenting a thought operating and a depression main part, sign a physical fixation for an object psychically not representable. These subjects have a real incapacity to perceive and symbolize the affect of psychic suffering as well borderline teenagers (self-harm). Having reminded the Freudian and psychoanalytical conceptions on the pain, the operating functioning and the self-harm behaviour, the authors will refer to certain sociological works describing certain characteristics of our post-modern social, cultural and linguistic organization to underline the impact of these in the increase of the behaviour of search for the pain to borderline patients or with the perception of the pain as only sign of a mental suffering impossible to symbolize. So, we notice that the loss of symbolic structuring of our post-modern civilization, the ascent in power of the thought operating, the social and domestic disorganizations, have a real cost on our contemporaries psychic and somatic health, particularly on the most numerous among them as teenagers.  相似文献   
39.
A case of postnephrectomy arteriovenous fistula of the right renal pedicle is reported here. The diagnosis was confirmed by angiography, and successful treatment was achieved using detachable balloon.  相似文献   
40.
Objective: To identify factors that affect operative mortality and morbidity and long-term survival after completion pneumonectomy. Methods: We retrospectively reviewed the charts of consecutive patients who underwent completion pneumonectomy at our cardiothoracic surgery department from January 1996 to December 2005. Results: We identified 69 patients, who accounted for 17.8% of all pneumonectomies during the study period; 22 had benign disease and 47 malignant disease (second primary lung cancer, n = 19; local recurrence, n = 17; or metastasis, n = 11). There were 50 males and 19 females with a mean age of 60 years (range, 29–80 years). Postoperative mortality was 12% and postoperative morbidity 41%. Factors associated with postoperative mortality included obesity (p = 0.005), coronary artery disease (p = 0.03), removal of the right lung (p = 0.02), advanced age (p = 0.02), and renal failure (p < 0.0001). Preoperative renal failure was the only significant risk factor for mortality by multivariate analysis (p = 0.036). Bronchopleural fistula developed in seven patients (10%), with risk factors being removal of the right lung (p = 0.04) and mechanical stump closure (p = 0.03). Overall survival was 65% after 3 years and 46% after 5 years. Long-term survival was not affected by the reason for completion pneumonectomy. Conclusion: Although long-term survival was acceptable, postoperative mortality and morbidity rates remained high, confirming the reputation of completion pneumonectomy as a challenging procedure. Significant comorbidities and removal of the right lung were the main risk factors for postoperative mortality. Improved patient selection and better management of preoperative renal failure may improve the postoperative outcomes of this procedure, which offers a chance for prolonged survival.  相似文献   
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