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101.
The authors report on their personal experience with percutaneous cholecystostomy (PC) in 36 cases of acute cholecystitis (AC). PC was successful in 34 cases, improving the clinical condition of the patients within the first hour following treatment and normalizing the laboratory data within 24-48 hours. Twenty-seven patients with calculous AC underwent cholecystectomy within 4-15 days. In 6 cases (3 calculous and 3 acalculous ACs) PC was the only treatment performed; in one case (calculous AC) PC was combined with lithotomy, the stone fragments being extracted via the cholecystostomy. According to literature reports, to date PC has been performed mainly--as an alternative to surgical cholecystostomy--on the patients unsuitable for cholecystectomy due to their age or to severe impairment of their conditions. In our experience, the procedure can be performed on a wider range of patients as a final (notably in acalculous AC) or temporary step (notably in calculous AC where it may allow cholecystectomy to be delayed and thus performed under better clinical conditions, with decreased morbidity and mortality risks).  相似文献   
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A male newborn infant was recognized having Fanconi-Bickel syndrome (FBS) in the neonatal period. The presenting clinical findings were hyperglycemia and polyuria detected during an episode of acute enteritis. Physical examination was normal, biochemical analyses were suggestive of FBS: glycosuria, proteinuria, phosphaturia, generalized aminoaciduria, and increased levels of urinary beta 2-microglobulin, serum glucose and serum alkaline phosphatase. The molecular genetic analysis showed homozygosity for mutations within the gene of the glucose transporter 2 (Glut 2), 1213 C>T. The patient demonstrated improved clinical and metabolic status following institution of diet with frequent small meals and galactose-free-milk as well as pharmacological treatment with phosphate and vitamin alpha-OH-D3. In conclusion, infants showing hyperglycemia and polyuria may be considered having FBS also in the neonatal period. Early institution of adequate caloric intake and replacement of electrolytes and vitamin D may avoid or reduce metabolic complications.  相似文献   
104.
Microorganisms have demonstrated several attributes that make them attractive for use in quick screening of effluents and chemicals for toxicity. The aim of this study was to evaluate the acute toxicity and mutagenicity of industrial effluents from São Paulo State using short-term microbial bioassays. Samples of industrial effluents and receiving waters were analyzed for acute toxicity by the Microtox system, a motility test using Spirillum volutans, growth inhibition of Pseudomonas fluorescens, and dehydrogenase assay; for mutagenicity, these samples were analyzed by Salmonella typhimurium (Ames test), Escherichia coli WP2, and Saccharomyces cerevisiae reversion mutation assays. Among the acute toxicity assays carried out in this study, the Microtox and S. volutans tests showed good sensitivity and general good agreement with the Daphnia similis assay, which demonstrates that these tests are potentially useful as toxicity indicators for the industrial effluents and receiving waters considered. In relation to mutagenicity assays, good results were obtained with the three methods tested. The detection of mutagens in the industrial effluents considered indicates that some constituents of these waste waters discharged in receiving waters can cause adverse biological effects and could be deleterious from a public health standpoint. The data of this research emphasize the importance of acute toxicity and mutagenicity assays as supplementary approaches for a rapid and efficient action in water pollution control, and for evaluation of potential toxic chemical effects.  相似文献   
105.
The retinal circulation of 35 patients (age, 30 to 71 years) with symptomatic internal carotid occlusion (22 cases) or severe inaccessible stenosis (13 cases) was studied both before and after superficial temporal to middle cerebral artery (STA-MCA) bypass surgery using ophthalmodynamometry (ODM) and intravenous fundus fluorescein angiography (IVFA). Ninety-four per cent of the patients were found preoperatively to have funduscopic findings or symptoms indicative of ocular ischemia. ODM values were abnormal preoperatively in 32 of 35 patients (91%), and improvement in ODM values for the ipsilateral eye was noted postoperatively in 25 patients (71%). ODM values obtained during the early (less than 3 months) and late (greater than 3 months) postoperative periods were significantly improved when compared to the preoperative values. IVFA values were abnormal in 25 of 29 patients (86%) preoperatively, and significant improvement was noted in 22 of 25 patients (88%) postoperatively. Preoperative patients with normal fundus examinations (10 cases) had significantly better values for IVFA and ODM than patients with venous stasis retinopathy. The findings of the study showed that STA-MCA anastomosis is beneficial in treating retinal ischemia secondary to ipsilateral severe inaccessible carotid artery stenosis or occlusion.  相似文献   
106.
Two recently developed tests for measurement of factor VIII/von Willebrand factor (FVIII/vWF), i.e. platelet agglutination by botrocetin and a kinetic latex antigen assay, were compared with ristocetin cofactor and electroimmunoassay, in respect with FVIII/vWF size-distribution. FVIII/vWF was measured in six cases of atypical von Willebrand's disease (type II), in gel-filtered fractions of normal cryoprecipitate and in the course of depolymerization of purified normal FVIII/vWF by disulfide reduction. Small molecular forms of FVIII/vWF from normal and variant type II plasma, and those derived by disulfide reduction of high-molecular weight FVIII/vWF, showed remarkably decreased reactivity in ristocetin-, botrocetin- and latex-assay. We conclude that for botrocetin-induced platelet agglutination, as well as for agglutination of antibody-coated latex particles, multiple interactions with repeating subunits of FVIII/vWF are required. As a practical consequence, the combined measurement of FVIII/vWF by the latex test and electroimmunoassay provides a simple tool for discriminating between the classical von Willebrand's disease and its variants.  相似文献   
107.
Human factor VIII/von Willebrand protein is a population of multimers which vary in size but contain apparently identical subunits. Large-molecular-weight forms possess higher ristocetin cofactor/von Willebrand activity than the native smaller oligomers. Disulfide reduction of large factor VIII multimers results in progressively decreasing molecular size and a loss of ristocetin cofactor activity. Small molecular forms of factor VIII were adsorbed onto gold granules (average diameter 20-30 nm) and thereby increased their ristocetin cofactor activity. The amount of adsorbed material and the extent of activation were dependent on the pH of the coiled suspension. The maximum recovery of von Willebrand activity was observed at pH 4.75. Aggregation of fixed human platelets by factor VIII-coated gold particles was dependent on ristocetin concentration and was not competitively inhibited by unbound low-molecular-weight factor VIII. These results suggest that the subunits of the native small factor VIII species possess potential binding affinity for platelet receptors, which is manifested following formation of large factor VIII polymers. We conclude that an optimal size of remarkably high molecular weight is required for efficient aggregation of platelets by factor VIII as occurs during the primary phase of hemostasis.  相似文献   
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BACKGROUND AND OBJECTIVE: Searching for nonrandomized studies in electronic databases is complicated because there is a variety of study designs and lack of standardization in the terminology. The purpose of this study was to develop and evaluate a method to limit search strategies according to study design of comparative nonrandomized studies (cNRSs). METHODS: Four updated Cochrane systematic reviews that included nonrandomized studies (cohort, case-control, and cross-sectional studies) of the effects of health care interventions were selected. Search strategies limited to study design were devised for each one of these topic areas in two electronic databases (MEDLINE and EMBASE). A progressive method (PM) and a fixed method for selecting the most appropriate search terms associated with study design of nonrandomized studies are suggested. RESULTS: The results showed that the sensitivity of search strategies (in two databases combined) limited to study design were between 90% and 100% for the PM using both controlled vocabulary (CV) and textwords (TWs) and between 95% and 100% for a fixed set of controlled vocabulary and TWs. CONCLUSIONS: It is possible and acceptable to use search strategies limited to study design of cNRSs of health care interventions.  相似文献   
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