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1.
Finasteride is standard medical treatment for androgenetic alopecia; however, no large studies with 5 years or more of follow up have been performed in Japan. The authors followed Japanese men with androgenetic alopecia treated with finasteride for 5 years to evaluate long‐term treatment efficacy. Of 903 men treated with finasteride (1 mg/day), 801 patients were evaluated over 5 years by modified global photographic assessment. Although the proportion of improvement was high (99.4%), modified global photographic assessment scores after 5 years of treatment were lower in patients with more advanced disease as measured by the modified Norwood–Hamilton scale. After separating patients into “sufficient” and “insufficient” efficacy groups according to the modified global photographic assessment score after 5 years (scores ≥6 and <6, respectively), multivariate analysis showed that independent risk factors of insufficient efficacy were age at start of treatment of 40 years or more (P = 0.021) and classification on the modified Norwood–Hamilton scale (P < 0.001), whereas presence of stress at start of treatment was a negative predictor (P = 0.025). In conclusion, continuous finasteride treatment for 5 years improved androgenetic alopecia with sustained effect among Japanese. Younger age and less advanced disease at start of treatment were the key predictors of higher finasteride efficacy.  相似文献   
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The effects of lithium treatment on serotonin (5-HT) receptors in rat frontal cortex and hippocampus were investigated. Long-term lithium treatment strongly blocked 5-hydroxytryptophan-induced head twitches, while acute lithium administration by itself induced head twitches in rats, and ketanserin blocked this acute lithium action. Long-term administration of lithium decreased the number of not only 5-HT2 receptors in the frontal cortex but also 5-HT1 and 5-HT2 receptors in the hippocampus in rats. Decreases in 3H-5-HT binding to hippocampal 5-HT1 receptors and 3H-spiperone binding to frontal cortical 5-HT2 receptors, caused by chronic lithium treatment, were abolished by co-administration of p-chlorophenylalanine, and were enhanced by co-administration with methiothepin. The turnover of 5-HT in either frontal cortex or hippocampus was facilitated by lithium, and co-administered methiothepin enhanced this facilitation. These results suggest that long-term lithium treatment causes the down-regulation of postsynaptic 5-HT1 and 5-HT2 receptors, in part probably through its action on presynaptic nerve terminals.  相似文献   
3.
In order to study the effect of nef gene expression on viral replication in monocytic cells, we established monocytic (U937 and THP-1) cell transfectants constitutively expressing the human immunodeficiency virus type 1 nef gene. We constructed a plasmid expressing the nef gene derived from an infectious clone, NL432, under the control of SR alpha promoter which can drive a high level of gene expression. We found suppressed viral replication in nef-expressing monocytic cells, although a negative effect of nef was observed, with some variation depending on the virus strain and the cell. We also observed that the expression of the surface CD4 molecule is inversely related to the expression of the nef gene, especially in the U937 transfectants. These results indicate that the suppression of viral replication and the down-modulation of CD4 molecule by nef gene expression occur in monocytic cell lines as in T cell lines.  相似文献   
4.
Exposure to nitrous oxide produced concentration-dependent analgesia in the mouse abdominal constriction test. Intracerebroventricular or intrathecal pretreatment with naltrexone or nor-binaltorphimine significantly reduced nitrous oxide analgesia. However, similar pretreatment with beta-funaltrexamine had no appreciable effect. These findings suggest that nitrous oxide analgesia involves spinal and supraspinal kappa-opioid receptors.  相似文献   
5.
Adjuvant and antitumor activities of synthetic 6-O-"mycoloyl"-N-acetylmuramyl-L-alanyl-D-isoglutamine were examined. All the synthetic 6-O-corynomycoloyl-, 6-O-mocardomycoloyl-, and 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine were active as adjuvants for cell-mediated immune responses. However, 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine was less active as an adjuvant on circulating antibody formation. It was shown that pyrogenic activity of N-acetylmuramyldipeptide was reduced by 6-O-acylation with mycolic acid, but not with nocardomycolic or corynomycolic acid. Tumor-suppression activity was observed by the synthetic 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine by using transplantable tumor in syngenic mice.  相似文献   
6.
Summary We studied the effects of BDM (2,3-butanedione monoxime) on the tetanic contraction of frog skeletal muscles using an X-ray diffraction technique. BDM significantly increased the resting equatorial intensity ratio (I 1,0/I 1,1). In sartorius muscle, 3mm BDM suppressed tetanic tension by 40–70% whereas the equatorial intensity ratio, which is 2.6 at rest, decreased to 0.75 during tetanus, close to the value in normal contraction (about 0.50). BDM (3mm) reduced the intensity increase of the 5.1-nm layer-line to 41%, that of the 5.9-nm layer-line to 24%, and the intensity decrease of the second myosin meridional reflection (at 1/21.5 nm–1) at 81%. In overstretched semitendinosus muscle, 3mm BDM did not significantly reduce the intensity increase of the second actin layer-line during activation, suggesting that enough calcium is released to activate the regulatory system and the regulatory proteins are intact. These results indicate that BDM suppresses tetanic tension by mainly inhibiting actin-myosin interaction. It has a smaller effect on the equatorial reflections and myosin layer-lines than on the actin layer-lines, suggesting that BDM-influenced myosin heads may bind to actin without following the symmetry of the actin helix.  相似文献   
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Well-developed germinal centers (GC) contain rapidly dividing surface immunoglobulin-negative (sIg-) B cells (centroblasts), and most of their progeny are sIg+ B cells (centrocytes) in a resting state. It has been predicted that somatic hypermutation occurs in centroblasts, whereas antigen-driven selection takes place in centrocytes. The present analysis indicates that murine GC B cells bearing sIg with specificity for an immunizing antigen are in a rapidly cycling state and increase exponentially in number to occupy spleen GC at high frequency during the 1st week after primary immunization; however, the number of these cells is significantly reduced in the 2nd week of immunization. During that period, these proliferating sIg+ GC B cells accumulate somatic hypermutations with nucleotide exchanges indicative of affinity maturation. These sIg+ GC B cells co-express B7-2, ICAM-1, and LFA-1, and have potent antigen-presenting activity which results in T cell activation in vitro. These observations indicate that the sIg+ GC B cells accumulate somatic hypermutations and undergo antigen-driven selection through proliferation, probably upon activation by T cells. This sIg+ GC B cell population may represent cell cycling centrocytes; however, the possibility that these may represent centroblasts undergoing re-expression of sIg could not be excluded.  相似文献   
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