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141.
The case of a 76-year-old woman presenting with focal liver lesions suggesting liver metastasis on CT is reported. A control CT performed one week later showed a normal liver. Biopsy revealed the diagnosis of focal liver steatosis. The final diagnosis of transient focal steatosis is proposed.  相似文献   
142.
OBJECTIVE: To determine whether pancreaticoduodenal resection (PDR) for benign and malignant disease can be performed safely, efficiently, and economically at a 50-bed community hospital. DESIGN: Retrospective review of 39 consecutive PDRs performed in an 18-month period. Indications for surgery, length of hospital stay, complications, and patient charges were analyzed. SETTING: A suburban 50-bed community hospital. PATIENTS: Thirty-nine patients (15 male and 24 female) referred for PDR for benign and malignant disease. MAIN OUTCOME MEASURES: Mortality and morbidity rates, length of hospital stay, care, and cost. RESULTS: Of 39 patients who underwent PDRs, 1 patient (2.6%) died of myocardial infarct. Intraoperative blood transfusions were required by 3 patients (8%). The mean postoperative hospital stay was 11 days. Twenty-four patients (62%) were discharged by day 11. Fifteen patients (38%) were hospitalized 11 to 24 days. Complications in 10 patients (28%) included pancreatic or biliary fistula (n = 6), upper gastrointestinal tract bleeding (n = 1), partial wound dehiscence (n = 1), bacteremia (n = 1), and pneumonia (n = 1). No patient required reoperation. Three patients were rehospitalized within 1 month. Mean patient charges were $21,864, and mean reimbursements were $19,669. CONCLUSIONS: Pancreaticoduodenal resection can be accomplished with low morbidity and mortality rates and a short stay at a community hospital. Thorough preoperative investigations to exclude unresectable lesions must precede every PDR for malignant disease. Mortality and morbidity rates in this series were similar to those for patients with similar diagnoses who were operated on in academic centers. Cost for and length of hospital stay of these 39 patients were significantly lower than those in other reported series.  相似文献   
143.
A threonine to isoleucine polymorphism at amino acid 164 in the fourth transmembrane spanning domain of the beta 2-adrenergic receptor (beta 2AR) is known to occur in the human population. The functional consequences of this polymorphism to catecholamine signaling in relevant cells or to end-organ responsiveness, however, are not known. To explore potential differences between the two receptors, site-directed mutagenesis was carried out to mimic the polymorphism. Transgenic FVB/N mice were then created overexpressing wild-type (wt) beta 2AR or the mutant Ile-164 receptor in a targeted manner in the heart using a murine alpha myosin heavy chain promoter. The functional properties of the two receptors were then assessed at the level of in vitro cardiac myocyte signaling and in vivo cardiac responses in intact animals. The expression levels of these receptors in the two lines chosen for study were approximately 1200 fmol/mg protein in cardiac membranes, which represents a approximately 45-fold increase in expression over endogenous beta AR. Myocyte membrane adenylyl cyclase activity in the basal state was significantly lower in the Ile-164 mice (19.5 +/- 2.7 pmol/min/mg) compared with wt beta 2AR mice (35.0 +/- 4.1 pmol/min/mg), as was the maximal isoproterenol-stimulated activity (49.8 +/- 7.8 versus 77.1 +/ 7.3 pmol/min/mg). In intact animals, resting heart rate (441 +/- 21 versus 534 +/- 17 bpm) and dP/dtmax (10,923 +/- 730 versus 15,308 +/- 471 mmHg/sec) were less in the Ile-164 mice as compared with wt beta 2AR mice. Similarly, the physiologic responses to infused isoproterenol were notably less in the mutant expressing mice. Indeed, these values, as well as other contractile parameters, were indistinguishable between Ile-164 mice and nontransgenic littermates. Taken together, these results demonstrate that the Ile-164 polymorphism is substantially dysfunctional in a relevant target tissue, as indicated by depressed receptor coupling to adenylyl cyclase in myocardial membranes and impaired receptor mediated cardiac function in vivo. Under normal homeostatic conditions or in circumstances where sympathetic responses are compromised due to diseased states, such as heart failure, this impairment may have important pathophysiologic consequences.  相似文献   
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The frequency of antibiotic resistance among bacteria in 4 intensive care units (ICUs) at a university hospital in Sweden was investigated annually from 1993 to 1996. An increase in ampicillin-resistant enterococci from 1993 to 1995 was seen which was due to a shift from Enterococcus faecalis to Enterococcus faecium. After a special infection control programme was instituted, the rate of ampicillin resistance among enterococci and the number of E. faecium isolates declined during 1996. The oxacillin resistance rates for Staphylococcus aureus were < or = 2%, while most of the coagulase-negative staphylococci (CNS) were oxacillin resistant. No vancomycin-resistant enterococci or staphylococci were seen. The ciprofloxacin resistance rate for CNS and Enterococci spp. were high. Relatively, high levels of resistance to cefotaxime and piperacillin/tazobactam among Enterobacter spp. were also seen. During 1995 and 1996 Pseudomonas aeruginosa showed increasing resistance to ceftazidime, ciprofloxacin and piperacillin/tazobactam. This was due to an outbreak among rather few patients. The overall resistance rates for Gram-negative bacteria were low for aminoglycosides and imipenem. From 1993 to 1996 the total antibiotic consumption decreased by 27% in the whole hospital and 16.5% in the ICUs. However, the reduced antibiotic consumption was paralleled with a 23% decrease in the total number of patients treated in the hospital from 1993 to 1996. In contrast there was an 11.5% increase in the number of ICU patients treated during this period. The conclusion is that all ICUs within a hospital should have a programme for 'on-line' antibiotic resistance surveillance of drugs used in that unit in order to change the empiric treatment when there is an increase in antibiotic resistance. It is also important to survey the antibiotic consumption in the ICUs in order to avoid further selective pressure on bacteria showing increased resistance rates.  相似文献   
146.
BACKGROUND: Ecstasy is a synthetic amphetamine which causes a wide variety of adverse effects. Hepatic toxicity was only recently demonstrated but can be quite severe. CASE REPORT: A 27-year-old male with no past medical or surgical history developed jaundice without fever. He was a regular user of ecstasy and had recently increased the number of doses consumed. No evidence of a viral, alcoholic, metabolic or autoimmune mechanism was found which could explain the hepatitis. Complete cure was obtained by discontinuing ecstasy. DISCUSSION: Few cases of ecstasy hepatic toxicity have been reported. Ecstasy was undoubtedly the causal agent in this case since other known causes of acute hepatitis were excluded, confirming the hepatotoxicity of ecstasy reported in the literature. The liver disease has been reported to range form acute regressive hepatitis to fatal liver failure. Iterative exposure can lead to fibrosis. The pathophysiological mechanism of this toxic effect is not well elucidated. Ischemia alone cannot explain all the clinical forms described, particularly cases without hyperpyrexia. Ecstasy must be added to the list of potential causes of acute hepatitis. Exposure must always be searched for in cases of acute hepatitis in young subjects.  相似文献   
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Many chronic medical conditions are manifested by alternating sojourns in symptom-free and symptomatic states. In many cases, in addition to their relapsing and remitting nature, these conditions lead to worsening disease patterns over time and may exhibit seasonal trends. We develop a mixed-effect two-state model for such disease processes in which covariate effects are modeled multiplicatively on transition intensities. The transition intensities, in turn, are functions of three time scales: the semi-Markov scale involving the backward recurrence time for the cyclical component, the Markov scale for the time trend component, and a seasonal time scale. Multiplicative bivariate log-normal random effects are introduced to accommodate heterogeneity in disease activity between subjects and to admit a possible negative correlation between the transition intensities. Maximum likelihood estimation is carried out using Gauss-Hermite integration and a standard Newton-Raphson procedure. Tests of homogeneity are presented based on score statistics. An application of the methodology to data from a multi-center clinical trial of chronic bronchitis is provided for illustrative purposes.  相似文献   
150.
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