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PURPOSE: To clarify the appropriate concentration and dose of hypertonic saline solution (HSS) for preventing delayed neuronal death in the hippocampal CA1 subfield after transient forebrain ischemia in gerbils. METHODS: Thirty gerbils were randomly assigned to five groups: physiological saline solution (PSS) group, ischemia/reperfusion treated with PSS 2 mL x kg(-1); 5% HSS group, treated with 5% HSS 2 mL x kg(-1); 7.5% HSS group, treated with 7.5% HSS 2 mL x kg(-1); 10% HSS group, treated with 10% HSS 2 mL x kg(-1); 20% HSS group, treated with 20% HSS 2 mL x kg(-1). Transient forebrain ischemia was induced by occluding the bilateral common carotid arteries for four minutes. Five days later, histopathological changes in the hippocampal area were examined, and the degenerative ratio of the pyramidal cells were measured according to the following formula: (number of degenerative pyramidal cells/total number of pyramidal cells per 1 mm of hippocampal CA1 subfield) x 100. RESULTS: In PSS and 20% groups, neuronal cell damage was observed five days after ischemia. In the other three groups, these changes were not observed. The degenerative ratios of pyramidal cells were as follows; PSS group: 91.6 +/- 5.6%, 5% HSS group: 7.2 +/- 1.6%, 7.5% group: 8.3 +/- 1.4%, 10% HSS group: 6.2 +/- 1.1%, 20% HSS group: 85.8 +/- 8.7% (P < 0.05; PSS and 20% HSS vs three other groups). CONCLUSION: This study demonstrates that 5, 7.5 or 10% HSS 2 mL x kg(-1) may prevent delayed neuronal death in the hippocampal CA1 subfield after cerebral ischemia/reperfusion in gerbils.  相似文献   
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In recent years, the most common causative organism of hospital infections has been methicillin resistant Staphylococcus aureus (MRSA). The major mechanism of beta-lactam resistance in MRSA is attributed to the production of a specific penicillin binding protein (PBP2'), which is a product of mecA gene, with extremely low binding affinities to beta-lactams. In the present study, we have established a rapid identification method of MRSA by sensitive detection of mecA gene using nested PCR. Nested PCR method amplifying the target DNA in two steps enhanced the efficiency of the second round amplification. By means of this method, mecA gene was successfully detected in clinical samples, such as blood, pus, sputum and feces within 3-4 hrs. Rapid diagnosis of MRSA-bacteremia is particularly important for prevention of sever systemic infection. There are some strains of S. aureus which possess mecA gene in spite of low minimal inhibitory concentration of DMPPC. In these strains expression of mecA gene is induced by contact of beta-lactams and they obtain methicillin resistance. Using nested PCR method, these latent MRSA are rapidly and certainly detectable. This method should be useful for early and effective detection of MRSA hospital infections.  相似文献   
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The sentinel node (SN) concept was originally proposed by several pioneers in the middle of the last century. After Donald Morton and his colleagues demonstrated the clinical significance of the SN concept in melanoma, it attracted vast attention in surgical oncology. At recent international conferences, a number of new approaches in this field for various solid tumors have been reported. Now, there are several possible applications with different technological aspects, such as individualized surgical management of solid tumors, multidisciplinary treatments, and novel therapeutic approaches. This article provides an overview of the future potential of SN technology.  相似文献   
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Determining the site and severity of blood loss is important in the management of children with gastrointestinal (GI) bleeding. Blood urea nitrogen (BUN) and serum creatinine (Cr) were measured on the day of hospitalization and the ratio of BUN/Cr was calculated in 11 children with 16 episodes of upper GI bleeding and 49 with lower GI bleeding. There was a significant difference between the two GI bleeding groups with regard to BUN/Cr ratio (p less than 0.001). When the ratio was 30 or above, the specificity of upper GI bleeding was 98% with a sensitivity of 68.8%. A linear relationship was found between the BUN/Cr ratio and delta Hb (delta Hb = 0.08 x BUN/Cr +/- 0.8 g/dl) for bleeding originating from the upper GI tract. This study confirms that measurement of the BUN/Cr ratio is useful for localizing the source of bleeding to the upper GI tract and also demonstrates its usefulness as an estimation of the severity of blood loss from the upper GI tract.  相似文献   
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Thrombotic microangiopathy (TMA) may develop after living donor liver transplantation (LDLT), but the mechanism is not fully understood. We retrospectively analyzed all patients undergoing LDLT at our center, including TMA patients, to elucidate the clinical characteristics and presentation and to determine which patients have a higher risk of occurrence of TMA. In all, 57 adult patients were reviewed after LDLT at our institution. TMA was diagnosed by sudden and severe thrombocytopenia, followed by hemolytic anemia with fractionated erythrocytes in the blood smear. Clinical features were compared between the TMA group and the non-TMA group. Of the 57 patients, 4 were diagnosed with posttransplantation TMA. ABO blood group (ABO)-incompatibility, cyclophosphamide (CPA), and recipient blood group (type O) were closely correlated with the occurrence of TMA. Thrombocytopenia appeared 1 to 5 days before hemolytic anemia. Coagulative function markers stayed at the same level after TMA, while marked elevation was shown in fibrinolytic function markers such as plasminogen activator inhibitor type 1 (PAI-1). TMA occurred at a higher prevalence in ABO-incompatible graft recipients. Additional factors associated with ABO-incompatible transplantation, such as an overdose of immunosuppressants, may affect the likelihood of TMA. Sudden and severe thrombocytopenia presented before hemolytic anemia and the serum levels of PAI-1 correlated well with the clinical course of TMA. In conclusion, early recognition of thrombocytopenia and elevation of PAI-1 is crucial to diagnose TMA especially in ABO-incompatible LDLT.  相似文献   
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A 75-year-old man was admitted to our hospital with the chief complaint of a choking feeling around the esophagus. Laboratory examinations revealed eosinophilia, and high levels of serum immunoglobulin (Ig) E. A computed tomography scan (CT) showed wall thickening of the esophagus and terminal ileum, and ascites around the liver. An endoscopic examination revealed mild mucosal edema in the esophagus, stomach, and small intestine. Biopsy specimens showed diffuse eosinophilic infiltration in the mucosa. We therefore diagnosed eosinophilic gastroenteritis. Oral prednisolone relieved clinical conditions and the CT image improved. This case was considered valuable, because there have been few reports of eosinophilic esophagitis in Japan.  相似文献   
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A new mutant, the Eisai hyperbilirubinemic (EHB) rat, shows no inherent expression of the canalicular isoform of the multidrug resistance protein (cMrp) in the liver. It has defective biliary secretion of organic anions such as bilirubin glucuronides, bromosulfophthalein (BSP), cysteinyl leukotrienes, glutathione (GSH) and bile acid sulfate and glucuronides. When rats were injected intravenously with CdCl2, biliary excretion of Cd over 30 min was 0.28% and 0.004% of the total dose in Sprague-Dawley (SD) and EHB rats, respectively. Six SD rats and five EHB rats were fed a diet containing Cd. Bile Cd was detected at the level of 2 ng/20 min in SD rats, but not in EHB rats. There was no significant difference of hepatic Cd concentration between SD and EHB rats. Furthermore, there were no significant differences of renal and intestinal Cd, and hepatic and renal metallothionein (MT) concentrations between the SD and EHB groups. Biliary excretion of reduced-GSH for 20 min was 1.3 ± 0.3 mg and 3.6 ± 0.9 μg in SD and EHB rats, respectively. Our results suggest that hepatobiliary excretion of exogenous Cd is mediated mainly via carrier transport, including a cMrp or GSH carrier, but that the lack of the transport pathway does not contribute to abnormal accumulation of Cd in the liver. Received: 12 August 1996 / Accepted 7 November 1996  相似文献   
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