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Retained biliary stones remain a common clinical problem in patients after surgery. Since 1984, the authors have used choledochoscopy in the treatment of suspected retained biliary stones in 75 patients. These procedures were performed in the radiology department with use of local anesthesia supplemented by an intravenously administered sedative and analgesic. A 15-F flexible fiberoptic choledochoscope was used. Fifty-one of the 75 patients were treated as outpatients. Treatment was successful in 74 of 75 patients; in one patient, intrahepatic stones were not completely removed. Electrohydraulic lithotripsy was used to fragment calculi in 11 patients (15%). Biopsies were performed in four patients (5%). Five minor complications occurred; three required overnight admission. Choledochoscopic-assisted removal of retained biliary calculi is a highly effective and safe procedure. Advantages over standard fluoroscopic stone removal include the ability to directly visualize and fragment adherent or impacted stones and visualize noncalculous filling defects, such as air bubbles, mucus, and biliary tumors.  相似文献   
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BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
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1. The disposition of AY-30,068 (I), a new tetrahydrocarbazole analgesic drug, was studied in mice, rats, dogs, rhesus monkeys, and man. 2. Oral doses of the 14C-labelled drug in aqueous solution were well absorbed in rodents, but absorption of oral doses of the crystalline drug in dogs was poor. Due to the virtual absence of serum metabolites in rats and dogs, the bioavailability of I was nearly identical to the extent of absorption. Although a small first-pass effect was observed in mice, unchanged I represented a major portion of serum radioactivity. 3. A linear increase in the serum concentrations of I occurred at doses between 0.05 and 25 mg/kg in rats, 0.1 and 50 mg/kg in dogs, and 1-160 mg in man. In rhesus monkeys given a 0.5 mg/kg oral dose, the Cmax and AUC of I were similar to values obtained following a corresponding dose in dogs. 4. After i.v. administration of a 1.0 mg/kg dose the terminal elimination half-life (t1/2 beta) of I was 4 h in mice and 9-10 h in rats and dogs. In rodents, dogs, and several human subjects, the elimination of I was interrupted by secondary peaks. Enterohepatic circulation was confirmed in bile duct cannulated rats, where the t1/2 beta of I was decreased to 2.4 h. In rodents the serum clearance and apparent volume of distribution of I were 0.04-0.2 l/kg.h and 0.5-0.8 l/kg, respectively, and 0.6 l/kg.h and 9.8 l/kg in dogs. 5. In rodents and dogs dosed with 14C-labelled I, radioactivity was excreted almost entirely in the faeces. No unchanged I was detected in rat bile, while about 70% of the radioactivity corresponded to conjugates of parent drug.  相似文献   
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Scabies     
Scabies is an ectoparasite caused by the mite Sarcoptes scabiei var hominis , an obligate human parasite. There are about 300 million cases of scabies in the world each year. Common predisposing factors are overcrowding, immigration, poor hygiene, poor nutritional status, homelessness, dementia, and sexual contact. Direct skin-to-skin contact between 15 and 20 minutes is needed to transfer the mites from one person to another. The diagnosis suspected with a clinical history of itch, worse at night, affecting other family members, clinical distribution, and appearance. Definite diagnosis relies on microscopic identification of the mites, eggs, or fecal pellets with 10% potassium hydroxide, ink enhancement, tetracycline fluorescence tests, or mineral oil; other methods include: epiluminescence light microscopy and S. scabiei DNA. The most commonly used treatment modalities are permethrin and ivermectin. Persistence of symptoms for 2–6 weeks after successful treatment is common. Most recurrences are because of reinfection from untreated contacts.  相似文献   
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PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors.  相似文献   
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Ultrasensitive bright field in situ hybridization assays using enzyme metallography (EnzMet) have been developed and validated, but little is known regarding the applicability of EnzMet for immunophenotypic detection of protein via IHC. Superior resolution via discrete metallographic deposits offers the potential for enhancing high-resolution immunophenotyping. Using high-complexity tissue microarrays (TMAs), 88 common solid tumors were evaluated by automated EnzMet (Nanoprobes and Ventana). Targets were chosen to assess the ability of EnzMet to specifically localize encoded antigens in the nucleus (estrogen receptor), cytoplasm (cytokeratins), and cytoplasmic membrane (HER2) in TMAs. Results were compared with conventional IHC diaminobenzidine (DAB) immunostaining. There was full concordance between the EnzMet and conventional IHC results. Furthermore, the EnzMet reaction products did not appreciably diffuse, were dense and sharply defined, and provided excellent high-resolution differentiation of cellular compartments in paraffin sections for the nuclear, cytoplasmic, and cell membrane-localized antigens evaluated. The higher density of elemental silver deposited during enzyme metallography permitted evaluation of core immunophenotypes at a relatively low magnification, allowing more tissue to be screened in an efficient manner. This preliminary study shows the utility of using enzyme metallography for high-resolution immunophenotyping in TMAs.  相似文献   
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