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101.
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The use of an electric freezer in human semen banking   总被引:1,自引:0,他引:1  
The use of an electric freezer for cryostorage of human semen is described. A simple method for semen freezing in liquid nitrogen after dilution with 7.5% glycerol was used. Thawing for quality analysis revealed only a small decrease (10%) in post-thaw sperm motility (59 +/- 1.4 vs. 53 +/- 1.8%; mean +/- SE, n = 12, P less than 10(-5)) and 14% in post-thaw sperm vitality (85.0 +/- 1.3 vs. 72.9 +/- 1.8%). After the freezing process, the samples, three of each donor, were cryopreserved in a regular electric freezer which maintained temperatures in the range of -85 degrees C (+/- 2 degrees C). The samples were stored for 1 week, 2 and 6 months, thawed and then assayed for motility and vitality. No effect of storage was found for a period up to 2 months. An additional decrease of 17.2% in sperm motility and 18% in sperm vitality were noted only after 6 months of preservation. The final motility and vitality rates of these sperm samples were 44 +/- 2.4 and 60 +/- 3.0%, respectively. According to these results, in cases of sperm storage for limited periods, it is recommended to cryopreserve human semen by the use of a combination of freezing in liquid nitrogen and storage of the samples in an electric freezer at -85 degrees C.  相似文献   
103.
PP1 and PP2A are members of the protein serine/threonine phosphatases (PPs) family and their activities have been proposed as a requirement for hormone- and cAMP-regulated steroid synthesis. These findings raise the question whether the PPs activity is increased by hormonal action in steroidogenic systems. Thus, the aim of the study was to evaluate the action of cAMP on the activity of PP1 and PP2A in MA-10 Leydig cells. Our results demonstrate that 8Br-cAMP stimulation produces a transient inhibition of PP2A activity. In contrast, PP1 activity remains unchangeable. As reported in other steroidogenic cells, cAMP-induced steroidogenesis in MA-10 cells is reduced by Cantharidin (Can) and also by Calyculin A (CA), two chemically unrelated PP1/PP2A inhibitors (data not shown). Taking into account the inhibitory effect of cAMP treatment on PP2A activity, the latest findings result paradoxical. Therefore, we next evaluated the action of these compounds on total protein synthesis. Can 10(-5) M and CA 10(-7) M markedly reduced total protein synthesis (35 and 50% respectively) in MA-10 cells, measured by 35S-methonine incorporation. These results suggest that hormone-dependent steroidogenesis is working through inhibition of PP2A-dependent dephosphorylation and the effect of PP1/PP2A inhibitors on steroidogenesis may be due to a general inhibition of protein synthesis rather than to a specific action on StAR protein induction.  相似文献   
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CASE REPORT: We describe a woman with optic disc pit and bilateral renal hypoplasia as a papillorenal syndrome. DNA analysis for PAX2 mutations revealed a heterozygous mutation (nucleotide 619 in exon 9). A first uncle and a cousin had the same PAX2 mutation. DISCUSSION: The association of optic nerve colobomas and renal anomalies comprises a autosomal dominant syndrome for mutations in the PAX2 gene. Ophthalmic and renal diseases are highly variable; the ophthalmologist must check for a renal problem when a coloboma is detected.  相似文献   
106.
Reports of coccidioidomycosis are rare outside the Western hemisphere. We report the case of a 57 year-old Israeli who had returned from California with pneumonia. As his condition had deteriorated despite macrolides and beta-lactams, coccidioidomycosis was suspected. Both sputum culture and serology confirmed the diagnosis. Conventional doses of fluconazole were marginally beneficial, and a complete resolution was achieved only with very high doses. Travel to the South-Western United States may expose travelers to this uncommon disease.  相似文献   
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OBJECTIVES: This study sought to determine adherence of physicians to tuberculosis (TB) screening guidelines among foreign-born persons living in the United States who were applying for permanent residency. METHODS: Medical forms of applicants from 5 geographic areas were reviewed, along with information from a national physician database on attending physicians. Applicant and corresponding physician characteristics were compared among those who were and were not correctly screened. RESULTS: Of 5739 applicants eligible for screening via tuberculin skin test, 75% were appropriately screened. Except in San Diego, where 11% of the applicants received no screening, most of the inappropriate screening resulted from the use of chest x-rays as the initial screening tool. CONCLUSIONS: Focused physician education and periodic monitoring of adherence to screening guidelines are warranted.  相似文献   
109.
We have studied the effects of 14-methoxymetopon (HS 198), a potent opioid agonist, on the responses to the tail electric stimulation test and plus-maze activity of adult male rats. The prototype mu agonist morphine was used as the drug of reference. Besides we addressed the effects of HS 198 on the serum corticosterone levels and on serotonergic systems of discrete brain regions. Both drugs were administered subcutaneously. Morphine (5 mg/kg) and HS 198 (30 microg/kg) induced a similar effect on the nociceptive test, with both drugs significantly increasing the threshold for the vocalization afterdischarge, which is related to the emotional component of pain. In the plus-maze, morphine (5 mg/kg) and HS 198 (20 and 30 microg/kg) induced similar increases in the percentages of entries and time in the open arms, two parameters related to the anxiety state of the animals. The results indicate that HS 198 is far more potent than morphine in reducing the emotive/affective component of pain and in inducing an anxiolytic effect. HS 198 (30 microg/kg) also induced parallel increases in the serum corticosterone levels and the hypothalamic serotonin content. A possible correlation between the anxiolytic action of the drug and its effect on the hypothalamic serotonergic system is suggested.  相似文献   
110.
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