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1.
We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM.  相似文献   
2.
Transrectal ultrasonotomography is useful in following patients with benign prostatic hypertrophy, because prostatic shape and weight are precisely assumed. We studied the effect of chlormadinone acetate (CMA) on benign prostatic hypertrophy. CMA (50 mg/day) was administered to 30 patients with benign prostatic hypertrophy. Weight reduction over 10% of the gland was noticed in 24 cases (80%). Mictional conditions were improved in 70% subjectively and in 71.4% objectively. However, the number of nocturia decreased in only 18.9%. Reduction rate of the weight was unrelated with the weight of prostate before administration of CMA. Duration of administration of CMA and the reduction rate were estimated. There was no definite difference in reduction rate for the first 15 months, but there was a slightly high reduction rate after administration of CMA for more than 24 months. In 3 cases, the shape and weight of prostate were studied after discontinuation of CMA. The size of prostate showed a tendency to increase gradually.  相似文献   
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T Ichinose  M Sagai 《Toxicology》1989,59(3):259-270
Rats and guinea pigs were exposed continuously to 0.4 ppm NO2, 0.4 ppm O3 or a combination of the two gases for 2 weeks. The concentration of lipid peroxides in lungs of rats and guinea pigs exposed to NO2 alone or O3 alone did not change. The lipid peroxide level of rats inhaling the combined gases also did not change. However, the level of lipid peroxides in guinea pigs exposed to a combination of the two gases was increased to 2.2 times of the control level, showing a synergistic interaction. No increases of antioxidative protective enzyme activities and of antioxidants (such as NPSH, VE, VC) in guinea pigs exposed to NO2, O3 or the combined gases were found. In rats, no changes in enzyme activities and of the antioxidant contents were observed after NO2 alone, but O3 exposure produced slight increases of NPSH, VC, and GPx-H2O2. On the other hand, in rats exposed to the combined gases, marked synergistic increased of many antioxidative factors such as NPSH, VC, G6PD, GPx-cum.OOH and GPx-H2O2 were found. The results show that those animals which are able to increase antioxidative protective factors in the lung following exposure to the combined gases do not respond with a significant increase in lipid peroxides. On the other hand, in animals with poor induction-ability of these factors lipid peroxides are formed. This might explain why guinea pigs were the most sensitive to the effects of the combined gases. Furthermore, it was shown that in guinea pigs the increased level of lipid peroxides and that in rats the increased activities of antioxidative enzymes and the increased contents of the antioxidants were synergistic following exposure to the combined gases.  相似文献   
6.
The characteristics of a glial Na+,K+-pump dependent on extracellular K+ within epileptogenic cortex were studied electrophysiologically, biochemically and histochemically in vitro using slices from cobalt-induced epileptogenic cortex of rat. When the extracellular K+ concentration ([K+]o) was varied between 4 and 40 mM, the mean slope of membrane potential plotted against [K+]o was about 57 mV in glia from the normal cortex (tissue A) and about 44 mV in glia from the epileptogenic cortex (tissue B); whereas no significant difference in the resting membrane potential of these tissues was observed. In glia from tissue B, a marked transient hyperpolarization above control level was caused by replacement of elevated [K+]o with the normal medium. Ouabain abolished these phenomena observed in glia from tissue B, but had no effect on the membrane potential during normal [K+]o. Reduction of extracellular Na+, Ca2+ and Cl did not significantly affect the membrane potential of glia from either tissue. In tissue A, the cells marked by intracellular injection of horseradish peroxidase after intracellular recording were protoplasmic astrocytes; in tissue B, fibrous astrocytes with abnormal processes predominated. K+-dependent stimulation of Na+,K+-ATPase activity of the astrocyte-enriched fraction and its membrane preparation from tissue B was much larger than that from tissue A. A certain amount of the reaction product of K+-pNPPase activity was seen on glial plasma membrane within tissue B but not on that from tissue A. The above findings suggest that a glial Na+,K+-pump within actively firing epileptogenic cortex may be modified to increase in its activity.  相似文献   
7.
A rare case of lentigo maligna in the oral cavity was investigated by light and electron microscopy. Cutaneous lentigo malignas often develop to malignant melanomas. However, the electron microscopic examination revealed that even though there were a large number of melanosomes, most of them were late stage and had membrane structure, and positive staining with HMB-45 was not recognized. From our findings, it is difficult to conclude that oral lentigo malignas develop malignant melanomas, and thus further studies are needed.  相似文献   
8.
The apolipoprotein(a) (apo[a]) gene encodes a protein component of lipoprotein(a) [Lp(a)] whose plasma levels vary widely among individuals. Hyper-Lp(a)-emia constitutes a risk factor for thromboembolic disease. We previously subclassified the apo(a) gene into four allelic types (A-D) by polymorphisms in the 5''-flanking region. To elucidate whether these polymorphisms affect the expression of apo(a), we measured plasma Lp(a) concentrations in vivo by ELISA and examined expression of the gene by an in vitro assay using its 5''-flanking region. Homozygotes of type C had significantly higher Lp(a) levels than those of type D. The relative expression of type C was also about three times higher than that of type D, which was consistent with the in vivo results. Deletion analysis revealed that the substitution of C by T (+93) led to negative regulation in expression of the gene, while the change of G to A (+121) led to positive regulation. These results indicate that the polymorphisms in the 5''-flanking region of the apo(a) gene affect the efficiency of its expression and, in part, play a role in regulating plasma Lp(a) levels.  相似文献   
9.
Background Prostate cancer is rare in Asia, but the number of patients is increasing in Japan. We conducted an epidemiological study of prostate cancer in Gunma Prefecture, Japan, to investigate the trends and characteristics of the disease.
Methods: The subjects were 1.411 prostate cancer patients newly diagnosed between 1985 and and 656 patients who died from prostate cancer between 1981 and 1992. The incidence and mortality rates were calculated by year, demographic region and age.
Results: The yearly incidence rate showed an increase but the mortality rate showed no marked fluctuations. There was no significant difference between urban and ruraI districts in either incidence or mortality rate. The incidence rate tended to be high in the northern part of the prefecture, but no marked variation in mortality rate was seen. The incidence and mortality rates in districts with a history of manganese mining were high compared to those in districts without mining. In contrast, the incidence and mortality rates in districts with a history of zinc mining were comparatively lower. Both incidence and mortality rates showed a marked increase with age. The age-specific incidence showed a double logarithmic relationship to age.
Conclusions: The increase of the yearly incidence rate might be due to changes in lifestyle and environmental factors, improved diagnostic techniques, and increased awareness among the general public regarding prostate disease. Further investigation is needed to clarify the pattern and the causes of regional differences in the incidence and mortality rates. The possibilities that manganese and zinc might be related to prostatic carcinogenesis are suggested. Int J Urol 1995:2:191–197  相似文献   
10.
Oral squamous cell carcinoma is the most common oral malignancy, and we performed electron microscopic and immunohistochemical investigation of the tumor. In patients with cervical metastasis, microvilli were developed and a small number of desmosomes were found, regardless of the width of the intercellular spaces. In patients without the metastasis, few microvilli were found in relatively wide intercellular spaces, or numerous microvilli were found in narrow intercellular spaces, and a large number of desmosomes were shown. However, these findings were different from those of tumors that had received radiotherapy, in which numerous microvilli and a small number of desmosomes were found in the nonmetastatic cases. Transferrin receptor, which is a marker of cell proliferation, was localized on the cell membrane, especially in microvilli. Ultrastructural similarity between the primary tumor and the metastatic tumor was recognized, however, the features of microvilli, desmosomes, and the intercellular spaces differed between them in most cases. It is suggested that microvilli might be related to the metastasis of oral squamous cell carcinoma cells. Immunohistochemically, the protein expression of p53 and pRb2/p130 was related to the clinical course of the patients with oral squamous cell carcinoma; the mechanism of the synthesis of these proteins should be investigated in order to understand the biological behavior of the tumor.  相似文献   
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