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1.
Balloon dacryocystoplasty: indications and contraindications   总被引:3,自引:0,他引:3  
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OBJECTIVE  Increased plasma concentrations of GH and increased GH responses to provocative stimuli are reported in patients with poorly controlled type I diabetes and are suggested to be related to complications. Our aim was to investigate GH concentrations in moderately controlled patients.
PATIENTS AND MEASUREMENTS  We have investigated IGF-I concentrations and fasting GH concentrations and the response to 1 μg/kg body weight GH-releasing hormone (GHRH) intravenously and/or to 150 μg clonidine intravenously in 77 moderately controlled patients with type I diabetes and in 46 healthy controls.
RESULTS  Median HbA1c in the patients was 8.5% (upper level of normal 6.3%). Fasting GH and GH concentrations after the administration of GHRH were not significantly different in patients with type I diabetes compared with normal controls. Fasting and stimulated GH concentrations after the administration of clonidine were significantly higher in the patients, but this could be explained by their lower age and body mass index compared with controls. In controls but not in patients there was a negative correlation between GH and glucose concentrations. IGF-I was significantly lower in patients with diabetes than in controls, even after correction for age, body mass index and sex.
CONCLUSIONS  Patients with moderately controlled type I diabetes mellitus have normal baseline and stimulated GH concentrations after the administration of GHRH or clonidine compared with healthy controls, when corrected for age, body mass index and sex. However, these 'normal' GH concentrations must be considered inappropriately high in view of the hyperglycaemia in these patients. The low plasma IGF-I concentrations might be responsible for the GH over-production.  相似文献   
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The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.   相似文献   
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We evaluated 14 patients with bilateral testicular tumour, one-sided tumour and contralateral carcinoma in situ (CIS) of the testis or testis tumour in single testis with respect to their fertility. We analysed semen parameters, serum hormones [follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone], testicular sonography, testicular volumes and testicular histology prior to further anti-cancer treatment. Ten out of 14 patients showed normal or reduced sperm concentrations, while 4/14 patients were azoospermic. Serum FSH levels showed a significant negative correlation with sperm concentrations in patients with testicular malignancies (r = -0.64, P = 0.025). Testicular volumes revealed a significant positive correlation with semen parameters in patients with testes that were affected by CIS (r = 0.733, P = 0.038). We conclude that even bilateral testicular cancer and/or CIS do not preclude fertility and, therefore, patients should be offered andrological investigation and therapy, including possibly surveillance strategy or the chance for cryopreservation of the semen prior to further treatment in order to preserve their chances for paternity.   相似文献   
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OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease.  相似文献   
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