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The genomic RNA of the Japanese encephalitis virus (JEV) Beijing-1 strain was reversely transcribed and the synthesized cDNA was molecularly cloned. Six continuous cDNA clones that cover the entire virus genome were established and sequenced to determine the complete nucleotide sequence of the JEV RNA. The precise genomic size was estimated as 10,965 bases long. With flanking 95 bases at the 5 and 583 bases at the 3 non-coding regions, one long open reading frame (ORF) was revealed encoding a virus polyprotein with 3,429 amino acid residues. Because of sequence homologies observed between JEV and other flaviviruses, the genome organization of JEV appears to be identical with other flaviviruses. Genetic variation detected among flavivirus genomes is consistent with the established serological relatedness between JEV and other members of flaviviruses. The secondary structure of the JEV genome is deduced and discussed concerning its involvement in genome replication.  相似文献   
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The effect of a synthetic steroidal anti-androgen, TZP-4238, on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Old male beagle dogs (5-9 years old) were divided into three experimental groups. Group 1 consisted of BPH controls. Groups 2 and 3 received TZP-4238 0.1 mg/kg/day and chlormadinone acetate (CMA) 0.3 mg/kg/day p.o., respectively, for 5 months. In group 1, glandular hyperplasia of the prostate was clearly detected. In contrast, TZP-4238 (Group 2) or CMA (Group 3) produced marked atrophy of the glandular epithelium. In addition, a histopathological study showed that TZP-4238 or CMA medication for 5 months exerted no effect on the testes and the pituitary luteinizing hormone (LH) cells. Therefore, it is suggested that TZP-4238 (0.1 mg/kg) or CMA (0.3 mg/kg) causes regression of spontaneous canine BPH without any histopathological effects on the testes and pituitary LH cells. However, slightly decreased serum testosterone levels were found in TZP-4238-treated animals, due apparently to a direct and/or indirect effect on the testes. Thus, it is suggested that a marginal antigonadotrophic effect cannot be excluded. It is concluded that TZP-4238 is a potent anti-androgen for the treatment of spontaneous canine BPH, without any negative influence on the function of the testes and the pituitary LH cells.  相似文献   
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The design of a noninvasive reflectance pulse oximeter that uses the same principle of transmittance pulse oximeter and analyses the oxygen saturation of arterial blood was described. Four sets of red and infra-red LEDs were used as light sources. The respective reflectance photoelectric outputs were used to make an internal calibration curve of the instrument relative to the arterial oxygen saturation values measured with a Co-Oximeter (OSM-3) in five healthy nonsmoking subjects during steady-state hypoxaemia. The accuracy of the present instrument was studied in six patients with respiratory failure. From 22 samples, a good correlation coefficient (0.98) with a standard deviation of 1.42 was obtained in the range between 73 and 100 per cent between the arterial oxygen saturation measured with the present instrument and that with the Co-Oximeter. The result strongly suggests the usefulness of this oximeter in monitoring patients with hypoxaemia.  相似文献   
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PURPOSE: The PSA level of prostate cancer patients generally declines after endocrine therapy, but elevates when the cancer relapses in most cases. However, the rate of elevation differs with the case. We investigated the PSA doubling time (PSA-DT) of the prostate cancer patients whose PSA declined after endocrine therapy and later re-elevated, and investigated the relationship with other parameters. PATIENTS AND METHODS: We investigated 55 prostate cancer patients who underwent endocrine therapy between 1991 and 1998. Their PSA re-elevated continuously after their PSA fell below 10 ng/ml after the endocrine therapy as the first line treatment. First, the correlation coefficients with time and PSA were calculated in order to decide whether their PSA elevation was exponential or linear. PSA-DT was calculated thereafter, and compared with the clinical stage, pathological differentiation, clinical relapse style, time from the beginning of the therapy to PSA relapse, pre-treatment PSA value, and prognosis. The relationship between PSA-DT and each clinical parameter was tested using the Kruskal-Wallis test. Differences in survival rates and PSA-DT were calculated using the log-rank test. RESULTS: PSA elevated exponentially after cancer relapsed. PSA-DT in all cases ranged from 0.5 to 26.3 months, with an average of 4.4 +/- 4.8 (S.D.) months and the median was 2.5 months. PSA-DT was significantly (p < 0.01) short when the pre-treatment clinical stage was high, the time from the beginning of the therapy to PSA relapse was short, or the pre-treatment PSA value was high. PSA-DT tended to be short when the pre-treatment pathological differentiation was low, but not significantly. PSA-DT tended to be short when the cancer relapsed as distant metastasis rather than regional relapse, but not significantly. Prognosis from the initial treatment and PSA relapse was significantly poor when the PSA-DT was short. CONCLUSIONS: PSA elevated exponentially in the relapsed prostate cancer patients after the endocrine therapy. PSA-DT was distributed in a very wide range, and this value was considered to reflect the malignant potential and prognosis of the cancer. PSA-DT may be useful for determining the strategy after relapse.  相似文献   
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A 70-year-old man was admitted to our hospital for treatment of an anterior mediastinal tumor. Although he was asymptomatic, an abnormal shadow was visible on chest radiography. CT revealed a heterogeneous tumor located in the anterior mediastinum. On MRI, the tumor demonstrated low signal intensity in T1-weighted images and high signal intensity in T2-weighted images. Laboratory data, including tumor markers, were mostly within the reference ranges. Although a CT-guided needle biopsy was performed, histologic diagnosis could not be confirmed. We resected the tumor with the thymus by median sternotomy. Histopathological examination demonstrated that the tumor was a multilocular thymic cyst with thymic hyperplasia and numerous lymphocytes. The lining epithelial cells gave positive reactions to immunohistochemical staining for carbohydrate antigen 19-9. Carcinoembryonic antigen and squamous cell carcinoma antigen levels in the cystic fluid were elevated. This case appeared to be an acquired thymic cyst with thymic hyperplasia. There are few reports of such cysts.  相似文献   
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Antidiuretic actions induced by two growth hormone (GH) isoforms (20 K- and 22 K-hGH; 0.2 and 2.0 mg/kg) were evaluated in rats, as fluid retention may cause oedema, one of the adverse effects of GH. Both GH isoforms (2.0 mg/kg) suppressed urine excretion in hypophysectomized rats (P< 0.01), but only the 22 K-hGH isoform (2.0 mg/kg) suppressed urine excretion in intact rats (P< 0.01). In addition, prolactin (PRL) suppressed urine excretion in intact rats (P< 0.05). In conclusion, 20 K-hGH has less potency in causing urine retention than 22 K-hGH and since 20 K-hGH is missing 15 amino acids found in 22 K-hGH, these amino acids may be important for the antidiuretic action of GH. Since prolactin suppressed urine excretion, a part of the antidiuretic action of GH may be related to PRL-R activation.  相似文献   
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Engineered skin substitutes are widely used in skin wound management. However, no currently available products satisfy all the criteria of usability in emergency situations, easy handling, and minimal scar formation. To overcome these shortcomings, we designed a cell‐free bandage‐type artificial skin, named “VitriBand” (VB), using adhesive film dressing, silicone‐coated polyethylene terephthalate film, and collagen xerogel membrane defined as a dried collagen vitrigel membrane without free water. We analyzed its advantages over in‐line products by comparing VB with hydrocolloid dressing and collagen sponge. For evaluation, mice inflicted with full‐thickness skin defects were treated with VB, hydrocolloid dressing, and collagen sponge. A plastic film group treated only with adhesive film dressing and silicone‐coated polyethylene terephthalate film, and a no treatment group were also compared. VB promoted epithelization while inhibiting the emergence of myofibroblasts and inflammation in the regenerating tissue more effectively than the plastic film, hydrocolloid dressing, and collagen sponge products. We have succeeded in establishing a cell‐free bandage‐type artificial skin that could serve as a promising first‐line medical biomaterial for emergency treatment of skin injuries in various medical situations.  相似文献   
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