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A questionnaire survey was carried out to examine the attitudes and practices of Australian and New Zealand intensivists with regard to brain death and organ donation. A return rate of 82.5% was achieved. Fifty-eight per cent had written evidence of their own wishes to donate organs and 94% would agree to donation from a dependent. At least one intensivist is involved in certifying brain death on 95% of occasions. Intensivists are involved in the request for organ donation over 90% of the time although one-third do not believe that it is their role to request organ donation. Although two-thirds believe that the family should always be approached for organ donation, another 52 out of 254 indicated that it was their (the intensivist's) role to decide if families should be asked for organ donation. Possible reasons for not requesting are language or other communication problems, perceptions of cultural differences and degrees of family distress. Twenty per cent of respondents do not provide haemodynamic support before brain death confirmation. Australian and New Zealand intensivists overwhelmingly support the concept of brain death, current methods of confirmation of brain death, organ donation and transplantation. Possible reasons behind loss of potential donors include decisions not to resuscitate both before and after brain death is confirmed. Perceptions of family grief and cultural differences clearly inhibit requests for organ donation. A very few units have an effective policy on approaching families about organ donation. Intensivists have almost exclusive control over requests for organ donation and thus bear a full professional responsibility for this element of hospital practice.  相似文献   
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OBJECTIVES: Disturbances in gastrointestinal function may result from disordered eating and may lead to increases in gastrointestinal (GI) symptoms. We compared GI symptoms in obese and non-obese binge eaters and non-binge eaters. METHODS: One hundred nineteen obese and 77 normal-weight females completed a questionnaire on bowel symptoms and binge eating behaviors for the previous 3 months. Based on binge behaviors and body mass index (> 30 kg/m2), individuals were grouped as obese binge eaters (n = 73), obese non-binge eaters (n = 43), non-obese binge eaters (n = 14), and normal-weight controls (n = 61). RESULTS: Obese binge eaters reported more upper GI symptoms than normal controls or obese non-binge eaters (p < 0.001). Compared with normal controls, nausea, vomiting, and bloating was 2-4 times more prevalent in both binge eating groups. Indigestion was more prevalent in both obese groups. Obese binge eaters reported more lower GI symptoms than normal-weight controls (p < 0.05). Binge eating in both weight groups was associated with more frequent abdominal pain and dyschezia. Obesity was associated with more frequent constipation, diarrhea, straining, and flatus, whether or not subjects reported binge eating. Chi-square showed a significant association between obesity, binge eating, and symptoms of irritable bowel syndrome, using the Manning criteria. CONCLUSIONS: Specific GI symptoms were associated with binge eating and obesity. Overall, symptoms were more prevalent and more severe in obese binge eaters. The high prevalence of GI symptoms in obese patients who indulge in binge eating should be considered in their evaluation and treatment.  相似文献   
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BACKGROUND: Computed tomography (CT) and magnetic resonance imaging (MR) are commonly used neuroimaging modalities for patients with signs or symptoms of neuro-ophthalmic disorders. Understanding the technology and clinical uses of these modalities is vital in patient management. METHODS/RESULTS: Basic instrument design and technology are presented together with a discussion of indications and contraindications to the use of these imaging techniques. Case reports are presented to illustrate the usefulness in diagnosis of orbital and neuro-ophthalmic disease. CONCLUSIONS: A basic knowledge of CT and MR helps the optometrist correlate imaging with clinical signs and symptoms of disease. This understanding also results in more effective communication with other health care providers and patients.  相似文献   
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The annual time-series analysis examines the impact of changes in per capita alcohol consumption (NIAAA,AEDS) on changes in community hospital admission rates (AHA) in the United States from 1950 to 1992 (n = 43). Increases in per capita alcohol consumption were expected to increase hospital admission rates contemporaneously and several years thereafter following an exponential risk function. Distributed lag models based on differenced data controlling for changes in: (1) per capita cigarette consumption; (2) private hospital insurance coverage; (3) the drinking age population; (4) per capita disposable personal income; and (5) health care regulatory interventions show a contemporaneous effect of per capita alcohol consumption on hospital admission rates. The time-series analyses imply that between 22-26% of US community hospital admissions are alcohol related. A comparable analysis indicates that per capita alcohol and tobacco expenditures contribute to approximately 28% of US community hospital admissions. The absence of statistically significant lagged effects is inconsistent with an exponentially declining risk functions. However, the contemporaneous effects of per capita alcohol and tobacco consumption suggest that a reduction in smoking and drinking will produce quick reductions in morbidity and hospitalizations.  相似文献   
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The thumb carpometacarpal joint is a common site of osteoarthritis. It has been hypothesized that peaks of localized stress on the dorsoradial or volar-ulnar regions, or both, of the articular surfaces of the trapezium and metacarpal lead to erosion of cartilage and may be responsible for the progression of the disease. The objective of this study was to determine the contact areas in this joint under the functional position of lateral (key) pinch and in the extremes of range of motion of the joint. These contact areas were assessed relative to the observed sites of cartilage thinning. Eight hands from cadavers of women and five from cadavers of men were tested in vitro with the thumb under a 25 N load in the lateral pinch position, and under small muscle loads (0-5 N) with the thumb in flexion, extension, abduction, adduction, and neutral positions. Contact areas of articular surfaces of the thumb carpometacarpal joint were determined for these positions using a stereophotogrammetric technique. The lateral pinch position produced contact areas predominantly on the central, volar, and volar-ulnar regions of the trapezium and the metacarpal. In three specimens, contact areas were distinctly separated between the dorsoradial and volar-ulnar regions, and in one specimen, from a man, contact occurred exclusively on the dorsoradial region of the trapezium. Using stereophotogrammetry, maps of cartilage thickness also were determined for a subset of nine specimens. The volar-ulnar, ulnar, and dorsoradial regions of the trapezium were the most common sites of thin cartilage, and these may be sites of cartilage wear.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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OBJECTIVE: The effect of cigarette smoking on gallbladder (GB) emptying and refilling after a fatty meal was examined in 10 healthy volunteers (four women and six men, mean age 27.6 yr). METHODS: On three different days, the subjects underwent in randomized order: a control test without smoking (C), or they smoked two cigarettes during the early (0-20 min; S0-20), or late (20-40 min; S20-40) phase of the meal-induced GB emptying. GB volumes were measured ultrasonographically before the meal and at 10, 20, 30, 40, 60, 90, 120, 150, and 180 min postprandially. Two-way ANOVA was applied for statistical assessment of the results. RESULTS: The fasted GB volumes amounted to 15.7 +/- 1.8 cm3 (C), 15.0 +/- 1.7 cm3 (S0-20), and 18.4 +/- 2.3 cm3 (S20-40), F2;18 = 1.524, NS. Maximum GB emptying was observed until 60 min after the meal, with a nadir of the GB volume amounting to 7.3 +/- 1.3 cm3 (C), 6.6 +/- 1.2 cm3 (S0-20), and 7.1 +/- 1.1 cm3 (S20-40). No significant difference was found between the stimuli tested when absolute GB volumes were considered: F2;180 = 2.725, NS. Analysis of the GB emptying-refilling curves normalized for the fasted GB volume revealed that a significant inhibitory effect was produced by smoking two cigarettes during the late phase of GB emptying on the subsequent GB refilling: F2;162 = 11.066, p < 0.001 for the whole curve, and F2;72 = 7.126, p < 0.005 for the refilling phase. A significant contrast was found next between S20-40 and the control day (p < 0.001 whole curve; p < 0.005 refilling phase only), as well as between S20-40 and S0-20 (p < 0.001 whole curve; p < 0.025 refilling phase only). CONCLUSION: We conclude that smoking two cigarettes does not disturb the fatty meal-induced GB contraction in healthy humans. Subsequent GB refilling is delayed if smoking takes place during the late phase of the postprandial GB contraction.  相似文献   
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Viral RNA load has been shown to indicate disease stage and predict the rapidity of disease progression in human immunodeficiency virus type 1 (HIV-1)-infected individuals. We had previously demonstrated that feline immunodeficiency virus (FIV) RNA levels in plasma correlate with disease stage in infected cats. Here we expand upon those observations by demonstrating that plasma virus load is 1 to 2 logs higher in cats with rapidly progressive FIV disease than in long-term survivors. Differences in plasma FIV RNA levels are evident by 1 to 2 weeks after infection and are consistent throughout infection. We also evaluated humoral immune responses in FIV-infected cats for correlation with survival times. Total anti-FIV antibody titers did not differ between cats with rapidly progressive FIV disease and long-term survivors. These findings indicate that virus replication plays an important role in FIV disease progression, as it does in HIV-1 disease progression. The parallels in virus loads and disease progressions between HIV-1 and FIV support the idea that the accelerated disease model is well suited for the study of therapeutic agents directed at reducing lentiviral replication.  相似文献   
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The two gene-duplicated cAMP binding domains in the regulatory subunits of cAMP dependent protein kinase are each comprised of an A helix, an eight-stranded beta-barrel, and a B and C helix (1). The A domain is required for high affinity binding to C, while the B domain regulates access to the A domain. Using a combination of a yeast two-hybrid screen coupled with deletion analysis, cAMP binding domain A of RI was dissected into two structurally and functionally distinct subsites, one that binds cAMP and another that binds the C subunit. The minimum stable subdomain required for binding to C in the 1-3 micromolar range is composed of residues 94-169, while residues 236-244, mapped to the C helix of cAMP binding domain A, were defined as a second surface necessary for high affinity (5-10 nanomolar) binding to C. This portion of the C helix, due to its position directly between the two subsites, serves as a molecular switch for either a cAMP-bound conformation or a C-bound conformation and can thus modulate interactions of cAMP binding domain A with cAMP, with C, and with cAMP binding domain B.  相似文献   
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