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991.
A retrospective survey of 44 children with colorectal perforating injuries secondary to shrapnel and high velocity bullets is presented. Seven patients had the injury limited to the colon or rectum. All patients were operated upon within 7 hr from the their colonic wounds and 20 underwent a colostomy. Five of the patients repaired primarily had their injuries to the left side of the colon or rectum. None of the patients undergoing primary repair suffered from an anastomotic leak. The mortality rate after primary repair was 16.6% and after colostomy 10%. The mortality was significantly different in the group of patients who had additional injuries where a colostomy procedure was associated with a lower mortality rate (11% versus 21%). Shock on admission and during operation affected survival adversely in all patients. The average hospital stay of survivors was 24 days with "primary repair" and 36 days with "colostomy."  相似文献   
992.
We tested the hypothesis that adenosine is involved in regulating substrate metabolism during exercise. Seven trained cyclists were studied during 30 minutes of exercise at approximately 75% maximal oxygen uptake (VO2max). Lipid metabolism was evaluated by infusing [2H5]glycerol and [1-13C]palmitate, and glucose kinetics were evaluated by infusing [6,6-2H]glucose. Fat and carbohydrate oxidation were also measured by indirect calorimetry. The same subjects performed two identical exercise tests, but in one trial theophylline, a potent adenosine receptor antagonist, was infused for 1 hour before and throughout exercise. Theophylline did not increase whole-body lipolysis (glycerol rate of appearance [Ra]) or free fatty acid (FFA) release during exercise, but fat oxidation was lower than control values (9.5 +/- 3.0 v 18.0 +/- 4.2 micromol x min(-1) x kg(-1), P < .01). Glucose Ra was not affected by theophylline infusion, but glucose uptake was lower (31.6 +/- 4.1 v 40.4 +/- 5.0 micromol x min(-1) x kg(-1), P < .05) and glucose concentration was higher (6.4 +/- 0.6 v 5.8 +/- 0.4 mmol/L, P < .05) than in the control trial. Total carbohydrate oxidation (302.3 +/- 26.2 v 265.5 +/- 11.7 micromol x min(-1) x kg(-1), P < .06), estimated muscle glycogenolysis (270.7 +/- 23.1 v 225.1 +/- 9.7 micromol x min(-1) x kg(-1), P < .05), and plasma lactate concentration (7.9 +/- 1.6 v 5.9 +/- 1.1 mmol/L, P < .001) were also higher during the theophylline trial. These data suggest that adenosine may play a role in stimulating glucose uptake and restraining glycogenolysis but not in limiting lipolysis during exercise.  相似文献   
993.
Recent years have seen much work in the development of dentifrices containing the antimicrobial agent triclosan, a broad spectrum antibacterial agent manufactured for use in oral products by the Ciba-Geigy Corporation. Studies have shown that the incorporation of this agent into dental products, in combination with a PVM/MA copolymer (the non-proprietary designation for a polyvinylmethyl ether/maleic acid copolymer), can provide several important dental therapeutic benefits, including an antigingivitis effect. A considerable amount of the research on the therapeutic benefits of such dentifrices has been reported in the literature. The present study is a component of a large-scale program of clinical research to investigate the anticaries effectiveness of fluoride dentifrices containing 0.3% triclosan and 2.0% PVM/MA copolymer. The study included two treatment groups, each consisting of adults living near the Kiryat Gat area in Israel, who were assigned to the use of one of the following sodium fluoride (NaF) dentifrices: 1) a dentifrice containing 0.3% triclosan and 2.0% PVM/MA copolymer in a 0.331% NaF/silica (1500 ppm F) base; or 2) a dentifrice containing 0.331% NaF/silica (1500 ppm F). Conducted in accordance with the guidelines for caries clinical studies published by the Council on Dental Therapeutics of the American Dental Association, the study employed clinical diagnostic criteria as described in the August, 1987 National Institute of Dental Research (NIH/NIDR) publication. Dental radiographs were not employed. Principal comparisons of the dentifrices tested were implemented through the construction of 90% confidence intervals for the ratio of mean 3-year caries increments using Fieller's Theorem. Of those subjects who met the initial inclusion/exclusion criteria for this study, 1,296 were available for the 36-month examination. DFS (resp., DFT) increments over this period were 5.21 (1.30) for the triclosan/copolymer dentifrice, and 5.23 (1.39) for the dentifrice without those additives. The confidence interval calculations for both incremental DFS and DFT support the conclusion that a dentifrice containing 0.3% triclosan and 2.0% PVM/MA copolymer in a 0.331% NaF/silica (1500 ppm F) base provides a level of anticaries efficacy which is "at least as good as" that provided by a dentifrice containing 1500 NaF/silica, without those additive agents. As such, the results of this clinical study clearly indicate that the addition of triclosan and a copolymer to a 1500 NaF/silica dentifrice does not compromise its anticaries efficacy.  相似文献   
994.
Autologous grafts are superior to their synthetic counter-parts for grafting arteries smaller than 6-mm diameter both in terms of acute thrombogenicity and chronic intimal hyperplasia. Endothelial cell (EC) coating of the blood contacting surface may reduce thrombogenicity of synthetic small diameter vascular prostheses. In this study, the survival of EC monolayers on synthetic 4-mm diameter arterial prostheses over short-term implantations (< or = 6 weeks) was examined. Graft types examined were expanded polytetra-fluoroethylene (ePTFE) and microporous polyurethane (PU). Lumenal coverage with ECs was achieved by culturing ovine ECs on prostheses treated by either physical adsorption or covalent binding of ovine fibronectin (Fn). An ovine carotid interposition model was used to examine the performance of EC coated ePTFE and microporous PU over implantation periods of 1, 3, and 6 weeks. Outcomes assessed at the end of each experiment were graft patency, area covered by ECs, and thrombus free surface area (TFSA). Fn concentration, cell density at the time of coating and prostacyclin production in vitro were similar for both graft types. Occlusion occurred more frequently in unseeded grafts compared with EC coated grafts over 3 and 6 week implantation periods; however, the difference was not significant (p = 0.099). In prostheses precoated with ECs, approximately 40-60% of the surface area remained covered with endothelial-like cells following the first postoperative week. Recovery of EC layers occurred rapidly thereafter with 80-90% coverage at 3 weeks. TFSA remained low in comparison to EC cover in these prostheses until between 3 and 6 weeks postoperatively, suggesting a lag phase in recovery of EC function of seeded cells. In contrast, EC cover of unseeded prostheses only achieved 10-30% at 3 weeks, primarily by pannus EC ingrowth from the adjacent artery. TFSA of unseeded grafts increased in direct proportion to EC cover over time suggesting that there was no lag phase in function of these ingrowing cells.  相似文献   
995.
BACKGROUND: The purpose of this study was to assess relations to blood pressure (BP) in individuals of markers of dietary protein in their 24-hour urine collections. METHODS AND RESULTS: INTERSALT (INTERnational study of SALT and blood pressure) was a cross-sectional study of 10020 men and women aged 20 to 59 years in 52 population-based samples in 32 countries worldwide, with quality-controlled standardized procedures and assessment of multiple possible confounders. Three measurements of dietary protein in 24-hour urine of each individual participant were studied: total nitrogen and urea as indexes of total protein intake, and sulfate as an index of sulfur-containing dietary amino acids. Repeat examination was performed in a random 8% of participants to assess reliability and to correct for regression-dilution bias. Significant independent inverse relationships were found between BP (systolic and diastolic) and both 24-hour urinary total nitrogen and urea nitrogen, with adjustment for age, sex, alcohol intake, body mass, and 24-hour urinary sodium, potassium, calcium, and magnesium. With adjustment for regression-dilution bias, it was estimated that systolic and diastolic BP were on average 3.0 and 2.5 mm Hg lower, respectively, for persons with dietary total protein intake 30% above the overall mean than for those whose dietary protein intake was 30% below the overall mean (12.94 versus 6.96 g/d urinary total nitrogen, equivalent to 81 versus 44 g/d dietary protein, respectively). For the association of these markers with diastolic BP, results were similar for younger (20- to 39-year-old) and older (40- to 59-year-old) persons and for women and men. For their relation to systolic BP, regression coefficients were larger both for those aged 40 to 59 years than for those aged 20 to 39 years and for women than for men. Nonsignificant inverse relations were recorded for urinary sulfate and BP. CONCLUSIONS: These INTERSALT findings lend support to the hypothesis that higher dietary protein intake has favorable influences on BP.  相似文献   
996.
CT showed egg shell calcification in the cervical lymph nodes in a patient with sinus histiocytosis with massive lymphadenopathy treated for 1 year with interferon. CT scans before interferon treatment had shown no nodal calcification.  相似文献   
997.
Surgical treatment is increasingly used for patients with medically re fractory seizures. Valproate (VPA) is an effective, widely used anticonvulsant in this patient population, but believed by some researchers to increase surgical bleeding because of quantitative thrombocytopenia and functional defects in platelet aggregation. Because we have observed no clinical evidence that perioperative administration of VPA increases blood loss or complications related to postoperative bleeding in patients undergoing temporal lobectomy at our institution, we sought to test this hypothesis. We made a retrospective review of the medical records of all patients who underwent epilepsy surgery at the University of California, San Francisco Medical Center, from September 1986 through January 1993. Patients who had a temporal lobectomy and whose medical records documented preoperative platelet counts and pre- and postoperative hematocrit and hemoglobin values were included. We excluded patients who had cranial surgery before temporal lobectomy and those with intracranial neoplasms or vascular malformations. Patients were divided into two groups: those who received VPA in the immediate preoperative period and those who had not received VPA recently. We compared the estimated surgical blood loss and the estimated change in red blood cell (RBC) volume between groups by unpaired t tests. The charts of 87 consecutive patients qualified for inclusion in the study. Patients in the VPA group had relative (but not absolute) thrombocytopenia preoperatively (235 +/- 64 vs. 277 +/- 69 k in the No-VPA group). There were no differences in the estimated blood loss, RBC volume, or in the incidence of postoperative transfusion. VPA apparently does not increase complications of hemostasis during therapeutic surgical resections for epilepsy. Therefore, we do not recommend routinely discontinuing VPA before craniotomy.  相似文献   
998.
OBJECTIVE: To test the hypothesis that the anti-apoptotic ability of Epstein-Barr virus (EBV) may result in altered expression of apoptosis-associated proteins in oral hairy leukoplakia (HL), we evaluated HL tissue and normal epithelium for these proteins by immunohistochemistry. MATERIALS AND METHODS: Twenty formalin-fixed, paraffin-embedded specimens of HL lesions and six specimens of normal control mucosa were selected from archived tissue specimens. Bcl-2, Bcl-x, Bax and p53 apoptosis-associated proteins were evaluated in immunohistochemically stained tissue sections according to staining intensity and pattern. The percentage of p53-positive basal cells was estimated in sequential fields. RESULTS: Generally, there were only slight differences in the expression of Bcl-2 and Bcl-x proteins in the epithelium of HL and control tissue. The staining for Bcl-2 was weaker in keratinocytes than in putative melanocytes and Langerhans cells. Equivocal diffuse cytoplasmic staining of prickle cells was also noted. Keratinocytes throughout the epithelium stained positively for Bcl-x protein, although upper layers were more weakly stained. The 'balloon' keratinocytes in HL were infrequently positive for Bcl-x. Bax staining in HL differed from that in control tissue in being more heterogeneous. The staining reaction in HL was weak to negative in upper epithelial levels where 'balloon' keratinocytes were located. Weak to moderate nuclear p53 protein staining was detected in a mean of 25.3% of basal keratinocytes in all but one of the HL specimens; weak staining was seen in only two control specimens. CONCLUSIONS: We found only slight immunohistochemical evidence that expression of the apoptosis-associated proteins is altered in HL. p53 appears to over-expressed in HL; we speculate that this may be related to up-regulation or stabilization of wild-type p53 protein related to EBV infection.  相似文献   
999.
A method based on DNA amplification and hybridization has been used for the rapid detection of Mycobacterium tuberculosis in blood samples from 38 hospitalized patients (15 human immunodeficiency virus [HIV] positive and 23 HIV negative) in whom localized or disseminated forms of tuberculosis were suspected. In 32 of these patients, the diagnosis of tuberculosis was eventually confirmed by conventional bacteriological or histological procedures. M. tuberculosis DNA was detected with the PCR technique in the peripheral blood mononuclear cells from 9 of 11 (82%) HIV-infected patients and in 7 of 21 (33%) HIV-negative patients (P < 0.01), while M. tuberculosis blood cultures were positive in 1 of 8 (12.5%) and 1 of 18 (5.5%) patients, respectively. PCR was positive in all cases with disseminated disease in both HIV-negative and HIV-positive patients and also in the HIV-positive patients with extrapulmonary tuberculosis. Seven samples from patients with documented illness other than tuberculosis and 12 specimens from healthy volunteers, including seven volunteers with a recent positive purified protein derivative test, were used as controls and had a negative PCR. These results suggest that detection of M. tuberculosis DNA in peripheral blood mononuclear cells may be a useful tool for rapid diagnosis of disseminated and extrapulmonary forms of tuberculosis, especially in an HIV-positive population.  相似文献   
1000.
OBJECTIVES: To analyze the mechanism of vasodilation and circulatory shock occurring in patients who are treated with isolated limb perfusion with melphalan and recombinant tumor necrosis factor (TNF)-alpha for locally advanced malignant tumors. To determine the role of nitric oxide, if any, by measuring plasma nitrite and nitrate concentrations. DESIGN: Observational survey. SETTING: A 12-bed surgical intensive care unit in a university referral hospital. PATIENTS: Eight patients treated with hyperthermic isolated limb perfusion. INTERVENTIONS: Ninety minutes of hyperthermic isolated limb perfusion with recombinant TNF-alpha (3 or 4 mg) and melphalan (10 to 13 mg/L limb volume). MEASUREMENTS AND MAIN RESULTS: All patients developed sepsis syndrome due to leakage of recombinant TNF-alpha from the perfusion circuit to the systemic circulation. Despite the presence of very high systemic TNF-alpha concentrations during and immediately after perfusion, and despite definite signs of hyperdynamic circulatory shock (increased heart rate, increased cardiac index, decreased systemic vascular resistance), nitrite and nitrate concentrations, as measured in plasma at several time points, were not increased. CONCLUSIONS: The hypothesis that in humans, TNF-alpha induces vasodilation and shock through activation of inducible nitric-oxide synthase and subsequent formation of excessive quantities of nitric oxide is not substantiated by our results. Normal nitric oxide metabolite concentrations were found in the presence of high TNF-alpha concentrations and shock. Other mechanisms that do not involve the nitric oxide pathway are likely to play a role in the generation of hypotension and septic shock in this setting.  相似文献   
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