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1.
Balloon dacryocystoplasty: indications and contraindications   总被引:3,自引:0,他引:3  
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BACKGROUND: Relatively few studies have been conducted linking decreasing intraocular pressure (IOP) to preservation of visual field. This investigation was conducted to determine if this link could be made and to compare the long-term effect of two ocular hypotensive agents on preservation of visual field. METHODS: In an observer-masked study, 189 patients with primary open-angle glaucoma received either timolol or pilocarpine by random allocation. The dose of antiglaucoma agent was increased from 0.25% to 0.5% twice daily for timolol or from 2% to 4% four times daily for pilocarpine if the initial IOP response was inadequate. After an on-treatment baseline, visual fields were followed every 4 months for 2 years using the Octopus program 32. RESULTS: Compared with timolol, significantly more patients receiving pilocarpine discontinued use because of inadequate IOP control (P < or = 0.01). By comparing the mean visual field scores, it can be seen that the pilocarpine group had a significantly worse score at all timepoints from month 4 to month 24. The pilocarpine group also had a greater mean number of test loci with decreased sensitivity of 5 or more decibels (dB) at all timepoints. The mean within-patient regression slope for timolol was 0.01 dB/month and for pilocarpine was -0.06 dB/month (P < 0.01). The study has shown that over a 2-year period, patients treated with pilocarpine 2% or 4% four times daily experienced a significantly greater visual field deterioration than that seen in patients receiving either 0.25% or 0.5% timolol twice daily. CONCLUSION: Although these data do not support a link between lowering of IOP and visual field preservation, treatment with timolol was associated with significantly less visual field loss than treatment with pilocarpine.  相似文献   
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Substitution therapies for orphan genetic diseases, including enzyme replacement methods, are frequently hampered by the limited availability of the required therapeutic substance. We describe the isolation of a pterin intermediate from bacteria that was successfully used for the therapy of a hitherto incurable and lethal disease. Molybdenum cofactor (Moco) deficiency is a pleiotropic genetic disorder characterized by the loss of the molybdenum-dependent enzymes sulphite oxidase, xanthine oxidoreductase and aldehyde oxidase due to mutations in Moco biosynthesis genes. An intermediate of this pathway-'precursor Z'-is more stable than the cofactor itself and has an identical structure in all phyla. Thus, it was overproduced in the bacterium Escherichia coli, purified and used to inject precursor Z-deficient knockout mice that display a phenotype which resembles that of the human deficiency state. Precursor Z-substituted mice reach adulthood and fertility. Biochemical analyses further suggest that the described treatment can lead to the alleviation of most symptoms associated with human Moco deficiency.  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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Molybdenum cofactor (Moco)-deficiency is a lethal autosomal recessive disease, for which until now no effective therapy is available. The biochemical hallmark of this disorder is the inactivity of the Moco-dependent sulfite oxidase, which results in elevated sulfite and diminished sulfate levels throughout the organism. In humans, Moco-deficiency results in neurological damage, which is apparent in untreatable seizures and various brain dysmorphisms. We have recently described a murine model for Moco-deficiency, which reflects all enzyme and metabolite changes observed in the patients, and an efficient therapy using a biosynthetic precursor of Moco has been established in this animal model. We now analyzed these mice in detail and excluded morphological brain damage, while expression analysis with microarrays indicates a massive cell death program. This neuronal damage appears to be triggered by elevated sulfite levels and is ameliorated in affected embryos by maternal clearance.  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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