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81.
TT virus (TTV) is a newly discovered virus from a patient with post-transfusion hepatitis. We investigated the frequency and pathogenesis of TTV infection in children. A semi-nested PCR assay was used to amplify TTV-DNA in serum samples from 254 ambulatory children without liver disease, 20 with hepatitis of unknown etiology, and 18 transfusion recipients or hemophiliacs. In positive samples, TTV-DNA was quantified by real-time quantitative PCR using a fluorescent probe. We detected TTV-DNA in 20% of children with hepatitis of unknown etiology, which was not statistically different from the 23% prevalence in ambulatory children. In transfusion recipients or hemophiliacs, the frequency was higher (50%) than that in ambulatory children (P = 0.01). Among ambulatory children, TTV-DNA was frequently detected in children with acute gastroenteritis (36%). TTV-DNA was detected in 10% of the infants under 6 months old, and 20% of the children from 7 to 12  months old. The prevalence was constant after the age of 1 year; however, the copy number of TTV-DNA was significantly higher in children under 1 year of age (mean: 105.4 versus 103.8 copies/ml, P= 0.008). Finally, TTV-DNA was quantified serially in three children with chronic hepatitis who were positive for TTV-DNA. The presence or amount of TTV-DNA was unrelated to the serum alanine aminotransferase level. These results indicate that TTV infection is common in children. The larger quantity of TTV-DNA in infants and the high prevalence of TTV in children of all ages suggest that TTV may be transmitted in early childhood. Its relationship to hepatitis is doubtful in children. Received: 8 April 1999  相似文献   
82.
We treated a 39-year-old woman with hypoproteinemia and anemia who had profuse gastric polyposis. Radiographic and endoscopic examination showed numerous polyps restricted to the stomach. The patient had pulmonary arteriovenous malformations in the left lung. Histological examination of the resected stomach revealed the gastric polyposis to be composed of cystic dilatation of the glands with small areas of adenocarcinoma. These findings were compatible with gastric juvenile polyposis (GJP) accompanied by gastric cancer. Analysis of genomic DNA revealed that the patient had truncating mutation of SMAD4, a responsible gene for juvenile polyposis (JP). Our case suggests that SMAD4 is possibly a responsible gene for GJP.  相似文献   
83.
A radioimmunoassay (RIA) for the measurement of activin A, which is identical to erythroid differentiation factor (EDF), has been developed. A specific antiserum against activin A/EDF was raised in rabbits using a mixture of recombinant EDF and polyvinyl pyrrolidone. Of the compounds tested this polyclonal antibody cross-reacted only with bovine inhibin (3.2%) and human TGF-beta (4.2%). The least detectable value in this assay was 0.06 ng/tube. The within- and between-assay coefficients of variation at three different concentrations were 3.6-9.8% and 3.4-7.7%, respectively. Using this RIA, immunoreactive activin A/EDF levels in various biological fluids and tissues were examined. The dose-response curves of porcine follicular fluid and ovarian extract were parallel to the standard curve, and porcine follicular fluid contained high activin A/EDF immunoreactivity (1050 ng/ml). On gel chromatography of porcine follicular fluid, the major immunoreactivity was eluted in the same position as authentic activin A/EDF. Human placental extract and amniotic fluid had relatively high immunoreactive activin A/EDF levels (174 ng/g wet wt. and 63.9 ng/ml, respectively), but the dose-response curve of amniotic fluid was not parallel to the standard curve. Among rat tissues, the ovary showed the highest activin A/EDF immunoreactivity (163 ng/g wet wt.) much lower than that of porcine ovary (1020 ng/g wet wt.). Low immunoreactive activin A/EDF levels were detected in most parts of rat brain (8.7-14.2 ng/g wet wt.), except for the pituitary gland (70.0 ng/g wet wt.). The initial plasma half clearance time (t1/2) of exogenous activin A/EDF was 14 min in the rat and the plasma FSH concentration did not change significantly during this period. These results suggest that this RIA system has sufficient sensitivity and specificity to measure activin A/EDF concentrations in biological materials, and that the reproductive tissues are the main sources of activin A/EDF.  相似文献   
84.
HLA-DR Antigens in Pemphigus among Japanese   总被引:2,自引:0,他引:2  
The frequency of HLA-DR4 was significantly increased at P < 0.02 in 37 unrelated pemphigus patients (62.2%), when compared with unrelated 73 healthy controls (30.1%). This antigen was more frequently found in pemphigus foliaceus (70.6%) than pemphigus vulgaris (55.8%).  相似文献   
85.
86.
This study investigated whether interleukin-10 (IL-10) gene promoter region polymorphisms are associated with susceptibility to or clinical presentation of type 1 diabetes. The frequency of -1082G/A, -819C/T, and -592C/A polymorphisms was analyzed in 128 Japanese patients with type 1 diabetes and in 107 healthy control subjects in a case-controlled study. The allelic and haplotypic frequencies of the IL-10 gene promoter region polymorphisms were similar in patients with type 1 diabetes and in control subjects. However, the -819T and -592A allele were associated with adult-onset (>18 years) of the disease (p = 0.037). Furthermore, the frequency of ATA haplotype was increased in adult-onset patients than that in early-onset patients (< or =18 years; p = 0.037). Among the genotypes comprising ATA haplotype, the frequency of ATA/ATA was significantly higher in adult-onset patients than in early-onset patients (p = 0.004). These results suggest that the IL-10 gene promoter polymorphisms are associated with the age-at-onset in Japanese patients with type 1 diabetes.  相似文献   
87.
In this study, we examined nine cases of advanced Japanese prostate cancer by comparative genomic hybridization (CGH) to detect chromosomal imbalances across the entire genome and to identify several new regions likely to contain genes important to the development and progression of this disease. These cases had been previously examined for numerical chromosomal aberrations by fluorescence in situ hybridization (FISH). By CGH, the following regions were found to be over-represented (gains), with fluorescence ratio values higher than the threshold: 4p, 6p, 8q, 11q, 12q, 15q, 16p, 17q, 20, and 21 (>4 cases); underrepresentation (losses) involved: 1q, 4q, 5q, 6q, 13q, 14q, and 22 (>4 cases). The shortest regions of overlap (SRO) of gains were noted at 8q24.1 through q24.3, 12q23, and 17q23 through q24 (>5 cases). The SRO of losses were seen at 5q14 through q21, 6q16.1 through q21, 13q21.3 through q22, and 14q21 (>5 cases). Notably, the gain of chromosomes 8 and 12 by CGH was in agreement with the FISH data, suggesting that the gain of chromosomes 8 and 12 may play an important role in prostate carcinogenesis. The genes on the SRO regions were also discussed in relation to oncogenes and bone metastases.  相似文献   
88.
Cinoxacin was administered to 30 outpatients with chronic complicated urinary tract infection for 57.3 days (average) and the following results were obtained. Clinical efficacy based on decrease of pyuria were "excellent" in 44.8%, "good" in 31.0%, "fair" in 24.1%, and "poor" in 0%; and, overall effectiveness rate reached 75.9%. As for side effect, diarrhea and nausea were observed in 2 and 1 patients, respectively. GOT and GPT elevation was also seen in one case. Cinoxacin long term therapy seems to be effective and useful to chronic complicated urinary tract infections.  相似文献   
89.
90.
Positron computed tomography (PCT) was performed in 3 normal volunteers and 21 patients with cerebrovascular diseases using a high resolution PCT device Positologica-I and three tracers11CO,13NH3, and18FDG. Relatively early lesions showed various accumulation patterns, and metabolism and perfusion mismatches were clearly shown by this measurement. One type of mismatch is luxury perfusion which had a slight increase of blood volume. Another type of uncoupling is misery perfusion. Remote effects of ischemic lesions also appeared on PCT with18FDG and13NH3. From our clinical results, the PCT method with a high resolution device and radiopharmaceuticals such as11CO,13NH3, and18FDG is very useful in the assessment of cerebrovascular diseases and in defining circulatory dysfunction in man.  相似文献   
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