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The effects of testosterone (T) and 17 beta-estradiol (E2) on the prostate of castrated rats were investigated by histopathological and immunocytochemical procedures. A significant increase in prostatic weight occurred after 6 weeks treatment with T alone and in combination with E2. The greatest increase in prostatic weight occurred after the administration of T plus E2. Histopathologically, glandular hyperplasia of the prostate was noted, and the number of bromodeoxyuridine (BrdU)-positive cells showed a significant increase over that induced by testosterone alone.  相似文献   
3.
Objective. To assess the diagnostic value of magnetic resonance imaging (MRI) as compared with radiographic findings in osteonecrosis in divers. Design and patients. MRI scans and conventional radiographs of the shoulder, hip and knee joints of 23 professional male scuba divers were reviewed together with their clinical findings and personal histories. Correlations between the MRI findings and the radiographic evaluation, clinical symptoms, and personal history were then investigated. Results and conclusions. Lesions found on MRI in 23 divers included 27 in 39 proximal humeri, 17 in 36 proximal femora, 13 in 32 distal femora, and 12 in 32 proximal tibiae. Diffuse, marginated, or irregular patterns were observed. No lesions were seen in epiphyses of the distal femur or proximal tibia. We tried to classify these MRI findings by location and appearance. MRI showed no patients with only one affected bone. A close correlation between the MRI findings and maximum diving depth was observed in the proximal humerus. MRI depicted bone lesions that could not be detected on the radiographs. A routine MRI investigation of the hip joints should be performed in every diver in whom osteonecrosis is diagnosed at another site, for early detection of femoral head osteonecrosis. MRI of the shoulder joint is also the best surveillance in divers who dive deeper than 15?m.  相似文献   
4.
Twenty patients with malignant lymphomas and 12 with acute leukemias were treated with intravenous administration of etoposide, 60-100 mg/m2/day for five days, repeated for three to four weeks. Eighteen cases of malignant lymphoma and nine of acute leukemia were evaluable. CR was achieved in three cases (16.7%) and PR in four cases (22.2%) of malignant lymphoma. Although CR was not achieved in any patients with acute leukemia, and PR was in three (33.3%), it was found that etoposide was most effective for the patients with the M4 or M5 subtype in the FAB classification. The most serious adverse effect of the drug was leukopenia in patients with lymphoma. In three patients (30.0%), the leukocyte count was lower than 1,000/mm3. Gastrointestinal complications, such as anorexia, nausea, vomiting and diarrhea occurred in 60.7% of all patients, but were not serious. Alopecia was observed in 73.1%. Intravenous administration of etoposide was apparently effective for the patients with malignant lymphoma of the diffuse mixed type, and this efficacy found in our study was the same as that for oral administration of etoposide reported by us previously.  相似文献   
5.
The body of a Japanese flounder (Paralichthys olivaceus) changes from a symmetrical to an asymmetrical form during metamorphosis. To obtain detailed information on the mechanisms of the migration of the right eye to the left side, soft and hard tissues in the head of larval flounders were examined using transmission electron microscopy (TEM). Retrorbital vesicles (Rvs) are pairs of sac-like structures under the eyes. It has been suggested that the asymmetrical development of Rvs, with the right (blind) one being bigger than the left, is the driving force behind eye migration. The present study revealed that the ultrastructure of the Rv sheath is quite similar to that of a lymphatic capillary. Thus, it is possible that the Rv is a part of the lymph system, and is probably related to the secondary vascular system in teleosts. If we assume that the Rv sheath has a high permeability to liquid, similar to lymphatic capillaries, it is not plausible that the active expansion of the Rv pushes the eyeball. On the other hand, the pseudomesial bar (Pb) is a bone that is unique to flounders and is present only on the right (blind) side. At the beginning of eye migration, an aggregation of fibroblast-like cells is observed in the dermis under the right eye, where the Pb will subsequently be formed. These cells have a well-developed rough endoplasmic reticulum (rER) and mitochondria, and are probably responsible for formation of the thick layers of collagen fibrils around them. Since it is unlikely that the active expansion of the Rv causes eye migration, the role played by the Pb and its rudiment becomes more significant in right eye migration in the Japanese flounder becomes more significant.  相似文献   
6.
Vascular tumors of the soft tissue display a wide spectrum of histologic features and biologic behavior. Flow cytometric DNA analysis was performed on 40 vascular tumors, including nine African endemic-type Kaposi's sarcomas, nine angiosarcomas, seven hemangiopericytomas, six glomus tumors, and nine capillary hemangiomas. Six of the nine angiosarcoma cases (67%) and one of the seven hemangiopericytomas cases (14%) were aneuploid. All benign vascular tumors and Kaposi's sarcomas were diploid. Clinically, five of the six angiosarcoma patients with aneuploidy died within 2 to 28 months, while the remaining patient, who had the smallest tumor (2 x 1 cm), survived more than 4 years after the initial diagnosis was made. All three angiosarcoma patients with diploidy died within 10 to 14 months. One hemangiopericytoma patient with aneuploidy died within 1 month. No cases of benign tumor recurred. These results suggest that most vascular tumors, which generally follow a benign clinical course, were diploid and that the majority of those with a poor outcome were aneuploid. However, flow cytometrically assessed DNA ploidy has no prognostic value in angiosarcomas or hemangiopericytomas.  相似文献   
7.
Bronchiolo-alveolar carcinoma (BAC) is a type of lung adenocarcinoma characterized by growth along the alveolar wall. It is divided into two subtypes: sclerosing BAC (SBAC), which has central fibrosis, and non-sclerosing BAC (NSBAC), which lacks central fibrosis. We compared the genetic alterations in these two types of BAC with those in atypical adenomatous hyperplasia (AAH). There were 39 cases of SBAC, 19 of NSBAC and 20 of AAH. To detect the loss of heterozygosity (LOH) we used the microsatellite markers D3S1234 and D3S1300 on chromosome 3p, IFNA and D9S144 on 9p, and TP53 on 17p. We also used polymerase chain reaction-SSCP analysis and direct sequencing to examine a point mutation of the p53 gene at exons 5-8. At the TP53 locus, the frequencies of LOH showed a statistical rank-difference correlation among AAH, NSBAC and SBAC. On chromosomes 3p and 9p there were no statistical differences of LOH among AAH, NSBAC and SBAC. We detected a significant statistical rank-difference correlation in the p53 mutation among AAH, NSBAC and SBAC. These findings suggest that a process of multistep carcinogenesis from AAH through NSBAC to SBAC might occur in some cases of adenocarcinoma, and LOH of 3p and 9p might be an early event of carcinogenesis, while the p53 mutation might be a later event.  相似文献   
8.
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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10.
We previously showed that an intraperitoneal infection with mouse hepatitis virus (MHV) persists in interferon-gamma (IFN-gamma)-deficient C57BL/6 (B6-GKO) mice and results in subacute fatal peritonitis, which bears a resemblance to feline infectious peritonitis. To examine the role of other host factors in MHV infection in mice, IFN-gamma-deficient mice with a BALB/c background (BALB-GKO) were infected intraperitoneally with MHV and compared with B6-GKO mice. In contrast to B6-GKO mice, BALB-GKO mice died within 1 week due to acute hepatic failure. The viral titer of the liver in BALB-GKO mice was significantly higher than that in B6-GKO mice. All hepatocytes in BALB-GKO mice were necrotic at 5 days post-infection, which was clearly distinct from large but limited lesion in the liver from infected B6-GKO mice. The serum alanine aminotransferase activity of infected BALB-GKO mice were higher than that of B6-GKO mice and was paralleled with the severity of the pathological changes and viral titers in infected mice. Administration of exogenous IFN-gamma to BALB-GKO partially inhibited the acute death. These results indicate that BALB-GKO and B6-GKO mice clearly show different diseases following MHV infection, although wild type counterparts of both mice apparently showed the same clinical course after MHV infection.  相似文献   
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