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PURPOSE: The present study was performed to investigate the protective effect of leuprorelin (LH-RH analog), on spermatogonia apoptosis induced by doxorubicin (DXR) in the Sprague-Dawley rat model. METHODS: Twenty-four adult male rats were divided into the following four groups: (i) control group; (ii) group given doxorubicin (intravenous injection, 8 mg/kg); (iii) group given leuprorelin (subcutaneous injection, 3 mg/kg); and (iv) group given both doxorubicin (intravenous injection, 8 mg/kg) and leuprorelin (subcutaneous injection, 3 mg/kg). Evaluation for quantification of apoptotic spermatogonia was made by the ratio of TUNEL-labeled spermatogonia versus 100 Sertoli cells in each seminiferous tubule. Two hundred seminiferous tubules of each rat were assessed. RESULTS: The ratio of apoptotic spermatogonia versus 100 Sertoli cells at stages II-IV of the groups given DXR (groups 2 and 4) were significantly higher than those of the other groups. However, the value at stages II-IV of the group given both DXR and leuprorelin (group 4) was significantly lower than that of the group given DXR (group 2). CONCLUSION: The significant prophylactic effect (P < 0.05) of LH-RH analog against doxorubicin-induced spermatogonial apoptosis was observed in a stage specific manner by microscopic evaluation with TUNEL.  相似文献   
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Background:  Bleeding is one of the main symptoms of internal hemorrhoids. However, the conventional Goligher's classification of internal hemorrhoids does not consider the severity of bleeding. We intended to establish a useful method for evaluating internal hemorrhoids using a colonoscope that reflected the severity of the symptoms.
Methods:  Using a colonoscope in the retroflexed and forward viewing position, 104 patients with symptomatic internal hemorrhoids were evaluated based on the criteria of range, form and red color signs (RCS). Range was determined by the circumferential distribution of internal hemorrhoids and scaled from 0 to 4. Form was determined by size and scaled from 0 to 2. The presence of RCS was also evaluated. Symptoms were determined by interview and scaled from 0 to 3. Patients were treated by endoscopic band ligation (EBL) and were examined endoscopically before and 4 weeks after the treatment.
Results:  Before the treatment, range, form and RCS were significantly correlated to bleeding ( P <  0.01), and form was significantly correlated to prolapse ( P <  0.05). The endoscopic classification scores at 4 weeks after EBL improved significantly (range from 3.25 ± 0.05–0.56 ± 0.08 [ P <  0.01] and form from 2.81 ± 0.04–0.56 ± 0.07 P <  0.01).
Conclusion:  The new endoscopic classification of internal hemorrhoids proved to be closely correlated to symptoms, particularly bleeding, and thus highly useful in evaluating the effectiveness of the treatment.  相似文献   
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To clarify the relationship between the direct transport from the rat nasal cavity to the cerebrospinal fluid (CSF) and the molecular weight of the drug, the transport of fluorescein isothiocyanate-labelled dextran (FD) with various molecular weights was investigated. FDs (average molecular weights 4400 (FD4); 9400 (FD10); 18 900 (FD20); 40 500 Da (FD40)) were administered nasally or intravenously to rats, and the concentrations in the plasma and the CSF were measured and compared. None of the FDs were detected in the CSF after intravenous administration. However, FD4, FD10 and FD20 were observed to appear in the CSF after nasal administration, whereas the concentration in the plasma was much lower than that after intravenous administration. FD40 was not detected even after nasal administration. In addition, the concentration of these FDs in the CSF decreased with the increase in the molecular weight of FDs. These findings show that drugs with a molecular weight up to at least 20 000 Da can be directly transported from the nasal cavity to the CSF and that the transport of FDs to the CSF is dependent on their molecular weights.  相似文献   
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In order to examine the effect of growth hormone on urinary pyridinoline excretion, 32 patients with complete or partial growth hormone deficiency had their urinary pyridinoline excretion measured while receiving growth hormone and for 14 days after it was discontinued. There was a significant positive correlation between increases in growth velocities during the first year of growth hormone administration compared to before it, and the ratio of the urinary pyridinoline excretion levels while receiving growth hormone to those after discontinuation. Therefore, urinary pyridinoline excretion rapidly decreased in patients with growth hormone deficiency when the administration of growth hormone was stopped. Exogenous growth hormone appears to stimulate bone resorption in these patients.  相似文献   
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Diagnosis of Small Pancreatic Carcinoma   总被引:1,自引:0,他引:1  
A retrospective analysis was performed to evaluate the clinicalsymptoms and abnormal test findings in small pancreatic carcinoma.Five hundred and thirty-six cases of pancreatic carcinoma withthe histology of duct cell carcinoma were collected from 14medical centers in Japan. In 440 of the cases, tumor size wasmeasured at the time of laparotomy or from the resected specimen.Three hundred and seventy-seven patients (86%) had a carcinomalarger than 3.0 cm; only 30% of these were resectable. Sixty-threepatients (14%) had a carcinoma of 3.0 cm or less, with resectabilityof 97%. Detecting a tumor of "3 cm or less" with a high probabilityof resectability is the objective of early diagnosis with theresulting possibility of a cure. In most cases these small carcinomaswere found easily when obstructive jaundice was present (73%).However, the estimated occurrence of obstructive jaundice associatedwith carcinomas of 3 cm or less was only 10% among the totalcases of pancreatic carcinoma studied. Therefore, it is necessaryfor early diagnosis to detect carcinomas of 3 cm or less presentingwithout jaundice. The symptoms of small carcinoma without jaundiceare weight loss, anorexia, upper abdominal pain, back pain anda palpable abdominal mass. Among the various available examinations,endoscopic retrograde cholangiopancreatography, computerizedtomography and ultrasonography were valuable in diagnosing thesesmall carcinomas.  相似文献   
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Immunogenic properties of second generation human tissue plasminogenactivator (tPA) derivatives were examined in chimpanzee andmouse systems. Five species of modified tPAs (mtPAs) (designated2660, 2663, 2810, 8000, and 9200), recombinant native tPA orbovine serum albumin (BSA) as a positive control were subcutaneouslyinjected nine times at suitable intervals into chimpanzees,genetically the closest species to man. These animals were testedfor antigen(Ag)-specific antibodies to the corresponding proteinsby means of enzyme-linked immunosorbent assay and Western blotanalysis. Neither 9200, one of the five mtPAs tested, nor tPAwas immunogenic, although BSA and the other four mtPAs wereimmunogenic under these conditions. Thus, an antigenic determinant was not exposed by the modification on 9200 and thismodified tPA is expected not to be immunogenic in humans. Inthe mouse studies, mice were immunized with mtPAs. Serum sam-piesfrom these animals were tested for antibodies to the mtPAs whichdid not concomitantly recognize native tPA by immune ad sorptionof the antibodies to tPA. The amount of such antibodies alterthe elimination of native tPA-reactive antibodies was littleor none when the serum samples from 9200 and from the othermtPAs, except 8000, were tested. Taking into consideration theresults of the chimpanzee studies, it can be concluded thatAg-specific antibodies are dominantly produced to unchangedepitopes present in modified proteins in the mouse system, inwhich the native protein is immunogenic. These results suggestthat the chimpanzee model should be useful to predict immunogenicityof second generation recombinant proteins in man, while themouse system adopted by us, which determines the newly generatedepitopes of the modified proteins, is not sufficient.  相似文献   
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