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41.
AIM: It has been proposed that gonadotropin-releasing hormone (GnRH) analog administered after testicular damage stimulates the recovery of spermatogenesis. However, GnRH analogs suppress the function of sex accessory organs. In this study, we investigated whether testosterone also stimulates the regeneration of rat spermatogenesis after exposure to busulfan. METHODS: Male Fisher rats were divided into three groups of five each and all rats were treated with busulfan, 25 mg/kg, intraperitoneally at week 0. Group A served as the control. The other two groups received testosterone enanthate, 8 mg/kg, subcutaneous injections at 3 week intervals two times before (group B) or three times after (group C) busulfan. States of spermatogenesis were evaluated by histology and by the number of spermatid nuclei per testis at week 25. RESULTS: The mean percentage of 'recovered' seminiferous tubules plus or minus standard deviation was 10.3 +/- 7.8% in group A and 2.1 +/- 1.2% in group B. In both groups, more than 80% of the tubules remained degenerated. However, testes of group C rats showed an improvement of up to 37.1 +/- 20.5% (P < 0.05). The significant recovery of spermatogenesis was also demonstrated in group C by counting the number of spermatid nuclei per testis ([78.8 +/- 57.5] x 106). However, the count was only (7.6 +/- 13.5) x 106 and (0.52 +/- 1.0) x 106 in group A and B, respectively. CONCLUSIONS: Testosterone administration after severe testicular damage enhanced the regeneration of spermatogenesis in rats. We assumed that supplementary doses of testosterone would be more practical for clinical application than GnRH analogs, because exogenous testosterone maintains androgenicity.  相似文献   
42.
To investigate the relationship between biliary mucin and ductular stone formation, mucin was isolated from hepatic bile using gel filtration on Sepharose CL-4B. The bile was obtained from 14 patients with stones in various sites of the biliary tract. The hexose content in the excluded fraction was significantly higher in patients with intrahepatic ductular stones (68.7 +/- 20.5 micrograms/mL; mean +/- s.d.) than in those with gall-bladder stones or extrahepatic ductular stones (23.8 +/- 8.1 micrograms/mL, 33.3 +/- 9.5 micrograms/mL; P less than 0.05), suggesting a higher concentration of mucin in the bile of patients with intrahepatic ductular stones. Ion-exchange chromatography on DEAE-Sephacel showed that most mucin from each material was negatively charged and electrophoretic studies indicated that it was composed mainly of high molecular weight (greater than 10(6)), sulfated glycoprotein. These results suggested that the mucin content of hepatic bile might have an important relation to the development of intrahepatic ductular stones.  相似文献   
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Antibody to p40tax (anti-p40tax) in serum specimens obtained sequentially from a human T cell lymphotropic virus type I carrier population of mothers and children were assayed. The prevalences of anti-p40tax at the initial sampling were 88% (7/8) in children and 55% (16/29) in mothers. Two of the seven positive children lost their anti-p40tax during the investigation period, resulting in a final prevalence of 63% (5/8) in children. However, anti-p40tax status was constant in all the 22 mothers with multiple serum samples (15 remained positive and seven remained negative). A decline in the absorbance value of EIA for anti-p40tax was observed in seven of the 15 anti-p40tax positive mothers. This decline may result in the disappearance of anti-p40tax in some of them.  相似文献   
44.
Four stereoisomers (I-LL, I-LD, I-DL and I-DD) of a cyclic depsidipeptide (I) containing a tryptophan and a 2-hydroxy-4-methylpentanoic acid residue were synthesized, and their taste and chymotryptic susceptibility were examined. Compound I-LL is a depsipeptide analog of a bitter principle BP-II, cyclo(-L-Trp-L-Leu-), obtained from casein hydrolyzate. All of the four stereoisomers of I are strongly bitter to taste. Another depsipeptide analog, L-aspartyl-L-2-hydroxy-3-phenylpropanoic acid methyl ester, of the sweet H-L-Asp-L-Phe- OMe showed bitter taste instead of sweet. Chymotrypsin hydrolyzed I-LL and I-LD in moderate rates, and I-DL and I-DD very slowly.  相似文献   
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KATSUJIRO SATO  MD    DAISUKE MATSUMOTO  MD    FUMIKO IIZUKA  MD    EMIKO AIBA-KOJIMA  MD    CHIAKI MACHINO  MD    HIROTAKA SUGA  MD    ASAMI WATANABE-ONO  MD    KEITA INOUE  MD    KOICHI GONDA  MD    KOTARO YOSHIMURA  MD 《Dermatologic surgery》2007,33(8):937-944
BACKGROUND: Although combined use of tretinoin (all-trans-retinoic acid; atRA) and hydroquinone improves various hyperpigmented lesions, the pharmacologic instability of atRA and atRA-induced irritant dermatitis are difficult unsolved problems. OBJECTIVE: The objective was to evaluate the efficacy and adverse effects of a newly formulated gel containing inorganic-coated atRA nanoscale particles (nano-atRA gel). METHODS: Nano-atRA gel was used in our two-phased bleaching protocol: 5% hydroquinone and 7% lactic acid ointment were used along with nano-atRA gel in the bleaching phase (2-8 weeks), and 5% hydroquinone and 7% ascorbic acid ointment were used alone during the healing phase (4-8 weeks). Eighty-four patients with facial hyperpigmented lesions were enrolled in this study, and 77 of them (88 lesions) followed up for more than 10 weeks were analyzed. RESULTS: Hyperpigmentation was improved in 84 of 88 lesions (95.5%) after a mean treatment period of 14.3 weeks and was almost eliminated in 52 lesions (59.1%). Nano-atRA gel caused exfoliation and scaling similar to that seen with conventional atRA gel, whereas the erythema seen in the bleaching phase appeared to be weaker. CONCLUSION: Nano-atRA gel can improve hyperpigmentation to a similar extent as conventional atRA gel. It also induces irritant dermatitis, but with less erythema.  相似文献   
47.
Abstract: A 62-year-old female visited our unit complaining of persisting diarrhea. She underwent a thymectomy for myasthenia gravis (MG) and a thyroidectomy for malignancy at age 58, and she was treated medically for MG fbllowing surgery. She also received a partial ileo-colectomy because of an intramural suppurative abscess of the terminal ileum at age 60. In her laboratory data, the anti-acetylcholine receptor antibody and antinuclear antibody were positive, and IgG as well as IgA were a high titer. X-ray and endoscopic examinations revealed the presence of stiff and narrow lesions accompanied by longitudinal ulcers of the descending colon, and rough and granular mucosa of the rest of the colon and stomach. An elemental diet was not effective, but her condition was relieved by the oral administration of prednisolone. This case was considered a case of inflammatory bowel disease ac-companied by MG and systemic immunological disorders.  相似文献   
48.
Abstract: Out of a total of 466 cases of early colorectal cancer, we analyzed 139 cases with submucosal invasion (sm cancer) according to tumor size, gross appearance, depth and degree of invasion, and the presence of adenoma components. Early colorectal cancers 11 -20 mm in diameter were the most common lesion in this group, and the percentage with sm cancer increased with tumor size. More than 70% of relatively small sm cancers, 6-10 mm in diameter, had moderate or massive submucosal invasion similar to that found in large sm cancers. Only 35% of 6-10 mm cancers had an adenoma component; the majority (65%) had no adenoma component. In marked contrast, 63% of sm cancers 11 -20 mm in diameter had an adenoma component and in sm cancer the percentage of tumors composed solely of cancerous tissue without an adenoma component was low. Similar results were obtained when only protruding type sm cancers, which accounted for the majority of sm cancer cases, were included in the analysis. Therefore, we believe that the protruding type sm cancer 6-10 mm in diameter is at a stage close to advanced cancer. It is possible that many 6-10 mm sm cancers have a histogenesis different from that of large sm cancers.  相似文献   
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