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81.
We used the qualitative Hanssen technique in albino rats to seek morphologic demonstration of tubular obstruction in two types of acute renal failure: one induced by folic acid and another by methemoglobin. Immediately after the intravenous injection of folic acid, 250 mg/kg body weight, the animals became almost anuric. Two to three hours after the injection, sodium ferrocyanide remained within the proximal convoluted tubules. After the intravenous injection of methemoglobin, 0.5 to 1.0 g/kg body weight, the animals became oliguric but not anuric. Sodium ferrocyanide injected with methemoglobin was seen mainly in distal tubules and collecting ducts 2 to 3 hours after the injection. The degree of tubular dilatation was more marked in the former model than in the latter, in agreement with the degree of oliguria. These morphologic findings were taken to indicate that the above two types of acute renal failure were caused by tubular obstruction rather than by intrarenal vasoconstriction and subsequent cessation of glomerular filtration. (Am J Pathol 87:323-330, 1977).  相似文献   
82.
Summary.  We have identified the herpes simplex virus type 2 (HSV-2) UL4 gene product using a rabbit polyclonal antiserum raised against a recombinant 6xHis-UL4 fusion protein expressed in Escherichia coli. The antiserum reacted specifically with a 27-kDa protein in HSV-2 186-infected cell lysates. The protein was not detectable in the presence of the viral DNA synthesis inhibitor, suggesting that the UL4 gene was expressed as a γ2 gene. Indirect immunofluorescence studies localized the UL4 protein within the nucleus as discrete punctate forms at late times postinfection. However, when expressed in the absence of other viral proteins, the UL4 protein was limited to the cytoplasm, indicating that an interaction with one or more other virus-induced proteins was responsible for the nuclear localization during infection. Subnuclear fractionation studies showed that the protein was released from the nuclear structure of infected cells by high salt treatment. Moreover, the UL4 protein was detected in purified virions and light particles. Received December 24, 1997 Accepted February 4, 1998  相似文献   
83.
BACKGROUND: More effective therapy is needed for the treatment of Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). The clinical efficacy of intravenous ulinastatin therapy was investigated in 3 Japanese pediatric patients with SJS or TEN. METHODS: Ulinastatin was given to 1 pediatric SJS patient and 2 pediatric TEN patients within 7 days (patient 1; SJS), 6 days (patient 2; TEN), or 4 days (patient 3; TEN) after the onset of the skin rash. Ulinastatin was administered intravenously at a dose of 7,500 U/kg/day (maximum dose: 300,000 U/day). No corticosteroids were given. After the skin lesions resolved, the ulinastatin dose was reduced to between 2,500 and 5,000 U/kg/day as maintenance therapy and then the drug was withdrawn. RESULTS: Erythema, fatigue, and fever improved within 12-36 h of starting the ulinastatin infusion, and the skin lesions resolved completely after 4-7 days of ulinastatin therapy. None of the patients had cutaneous or ocular sequelae. No patient developed secondary infection or relapse and ulinastatin therapy caused no side effects. CONCLUSION: Ulinastatin dramatically reduced the febrile period with no adverse effects and was very safe in this study. Ulinastatin appears to be a useful and effective therapy for controlling SJS and TEN without sequelae.  相似文献   
84.
A case of the syndrome of sea-blue histiocyte is presented in a 53-year-old Japanese woman, which is the first recorded case in Japan. The patient had hepatosplenomegaly, bleeding manifestations, mild thrombocytopenia, fatty metamorphosis and cirrhosis of the liver, as well as abnormal serum lipid profiles. Her parents were consanguineous and her maternal grandmother with hepatomegaly died of hepatic failure. Histologically, peculiar histiocytes containing numerous, intracytoplasmic sea-blue stained granules on May-Giemsa stain were demonstrated in biopsy materials of the bone marrow, lymph node and liver. The sea-blue granules in these histiocytes proved to have histochemical staining characteristics of lipogenic ceroid-like pigment. Ultrastructurally, these granules showed membrane-bound, pleomorphic inclusions of heterogeneous nature, including electron-dense amorphous or variegatedly osmiophilic, frequently laminated materials. Enzyme cytochemically, localization of acid phosphatase activity was demonstrated in and around the intracytoplasmic inclusions. With regard to the pathogenesis of the sea-blue histiocytes in this case, it may be suggested that the existence of the abnormality in lipid metabolism plays an important role in intralysosomal ceroidogenesis in these histiocytes.  相似文献   
85.
A light-addressable potentiometric (silicon) sensor was used in an immunofiltration procedure for the detection of pathogenic bacteria. Yersinia pestis was detected by filtering the cells onto nitrocellulose membranes and then filtering anti-Y. pestis mouse monoclonal antibody and anti-mouse immunoglobulin G-horseradish peroxidase conjugate. For Neisseria meningitidis detection, mouse monoclonal antibody to the major outer membrane protein of this bacterium was coupled directly to horseradish peroxidase. N. meningitidis cell suspensions were filtered onto polycarbonate membranes, and the enzyme conjugate was allowed to react with the filtered bacteria. The presence of both enzyme conjugates was determined potentiometrically with the silicon sensor. The sensitivity of this technique relative to that of an enzyme-linked immunosorbent assay for N. meningitidis was determined. Fewer than 1,000 bacterial cells could be detected with the silicon sensor in a 20-min assay, whereas a 2.5-h enzyme-linked immunosorbent assay with the same antigen and antibody preparations was significantly less sensitive.  相似文献   
86.
Summary In a series of 79 cases of primary esophageal carcinoma resected at The Center for Adult Diseases, Osaka, there were six tumors with specific histopathologic features valid for the diagnosis of argyrophil cell carcinoma. Of the 6 tumors, 3 were studied electron microscopically and assay for ACTH content was performed on 4 tumors.Clinically, the ages of the 6 patients ranged from 56 to 71 years; two were women and four men. Four of the 6 patients died with widespread tumor recurrences within 9 months of operation.Microscopically, the 6 tumors were composed largely or almost entirely of small, spindle-shaped cells resembling those of oat cell carcinoma of the lung, and were characterized by the arrangement of tumor cells in solid sheets or anastomosing cords, the presence of argyrophil tumor cells, and the deposits of amyloid. Electron microscopically, the three tumors contained neurosecretory-type granules. Using bioassay or radioimmunoassay ACTH activity in the tumor tissues was detected in 3 out of the 4 tumors determined.From the light and electron microscopic characteristics and the assay evidence, it seems reasonable to conclude that the 6 tumors are endocrine polypeptide producing tumors (apudomas) that arise from argyrophil cells normally found among the basal cells of the esophageal mucosa, and that they represent a distinct histopathologic entity clearly distinguishable from other types of esophageal carcinomas.Supported in part by a Grant-in Aid for Cancer Research from the Ministry of Education, Science and Culture, and the Ministry of Health and Welfare, JapanThe authors are grateful to Prof. H. Imura and Dr. Y. Hirate, Department of Internal Medicine, Kobe University School of Medicine for their interest and performing the assays for ACTH on the tumor tissues.  相似文献   
87.
Histochemical and biochemical analyses were performed in order to examine the relationship between myosin light-chain (LC) isoforms and fibre-type distributions in whole human skeletal muscle. Muscle biopsies were obtained from the vastus lateralis muscle in six healthy men, and analysed for the relative area occupied by each fibre type (percentage of fibre type area) and the molar ratio of each LC isoform. The percentage of type I fibre area was positively correlated with the molar ratio of slow LC (LC1s and LC2s) to total LC. The regression line was located below the line of unity. Also, the ratio of percentage of type II fibre area to that of type II fibre area was positively correlated with the molar ratio of the fast alkali LC LC1f to fast alkali LCs LC1f and LC3f. These results support previous study, having shown that in human skeletal muscle some type I fibres express various amounts of fast LC in addition to slow LC and suggest that fast myosin heavy-chain HCII a is favourably associated with LC1f, whereas HCIIb is favourably associated with LC3f.  相似文献   
88.
89.
The experimentally induced cryptorchid mouse model is useful for elucidating the in vivo molecular mechanism of germ cell apoptosis. Apoptosis, in general, is thought to be partly regulated by the ubiquitin-proteasome system. Here, we analyzed the function of two closely related members of the ubiquitin C-terminal hydrolase (UCH) family in testicular germ cell apoptosis experimentally induced by cryptorchidism. The two enzymes, UCH-L1 and UCH-L3, deubiquitinate ubiquitin-protein conjugates and control the cellular balance of ubiquitin. The testes of gracile axonal dystrophy (gad) mice, which lack UCH-L1, were resistant to cryptorchid stress-related injury and had reduced ubiquitin levels. The level of both anti-apoptotic (Bcl-2 family and XIAP) and prosurvival (pCREB and BDNF) proteins was significantly higher in gad mice after cryptorchid stress. In contrast, Uchl3 knockout mice showed profound testicular atrophy and apoptotic germ cell loss after cryptorchid injury. Ubiquitin level was not significantly different between wild-type and Uchl3 knockout mice, whereas the levels of Nedd8 and the apoptotic proteins p53, Bax, and caspase3 were elevated in Uchl3 knockout mice. These results demonstrate that UCH-L1 and UCH-L3 function differentially to regulate the cellular levels of anti-apoptotic, prosurvival, and apoptotic proteins during testicular germ cell apoptosis.  相似文献   
90.
Recently, genomic DNA of the novel TT virus (TTV) was isolated from patients suffering from posttransfusion hepatitis of unknown etiology. We examined sera from 197 children who visited the Department of Pediatrics at Toyohashi National Hospital. Sera were tested for TTV DNA by seminested polymerase chain reaction (PCR) using a set of primers synthesized according to the published TTV sequence. Ten children were found to be positive for TTV (5.1%). All positive PCR products were directly sequenced in both directions using a fluorescent dye terminator cycle sequencing system. The sequences were compared by a multiple sequence alignment and a phylogenetic tree was constructed. The phylogenetic tree showed that two of the TTV isolates found in the present experiment did not belong to any of the phylogenetic groups previously reported.  相似文献   
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