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81.
Movement alterations as spermatozoa are washed and capacitated in preparation for the zona-free sperm penetration assay were investigated using a videomicrographic computer-assisted system for tracking and analysis of sperm trajectories. Thirty-three semen samples from infertile men and 17 fertile controls were studied. Despite significant differences on the sperm penetration assay, univariate comparisons of movement characteristics between infertile and control samples failed to detect differences. For all samples combined, significant alterations in movement characteristics were detected after washing. After an 18-hour sperm capacitation, mean velocity, head yawing amplitude, and head yawing frequency still were significantly increased over seminal plasma values. Videomicrographic motion analysis thus allows detection of changes that are consistent with hyperactivated motility, as has been described for capacitating spermatozoa. 相似文献
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Atlanto-axial rotatory fixation (AARF) is an uncommon condition which is often missed at presentation because of its rarity and the relative subtlety of plain film X-ray findings, but early detection and appropriate management are vital for a cure. We describe three cases in which the use of spiral computed tomography scanning with 3D and sagittal reconstructions greatly aided diagnosis and management. The 3D images gave a more graphic picture of the overall alignment of the upper cervical spine and the skull base, while the sagittal reconstructions demonstrated the presence or absence of compensatory atlanto-occipital subluxation. The literature is briefly reviewed. 相似文献
84.
We studied 80 children with tinea capitis without kerion to define the epidemiology and clinical characteristics of tinea capitis and to compare the therapeutic efficacy of griseofulvin and ketoconazole for treatment of this disorder. Patients ranged in age from 2.1 to 11 years (median, 5.2 years). Trichophyton tonsurans (74%), Microsporum canis (13.5%) and Trichophyton mentagrophytes (2.7%) accounted for 90% of the infections. Pretreatment KOH slide preparations were positive in 69% of patients with alopecia and in only 29% of those with diffuse scale with little hair loss. Sixty-three patients were randomly assigned to receive ketoconazole (5 mg/kg/day) or griseofulvin (15 mg/kg/day). The treatment groups were comparable with regard to age, sex, duration of lesions prior to treatment and type of lesions. The percent of patients with positive cultures on therapy at 4, 6, 8, and 10 weeks and the mean time to a sterile culture were significantly larger (P less than 0.01) in ketoconazole (8 weeks) than in griseofulvin-treated (4 weeks) patients. The time for complete scalp clearing was significantly longer in patients who received ketoconazole (median, 108 days) compared with those who were treated with griseofulvin (median, 60 days) (P = 0.01). 相似文献
85.
BACKGROUND: Mesenteric panniculitis is a rare condition with no standard therapy. AIM: To assess the safety and efficacy of thalidomide for the treatment of patients with symptomatic mesenteric panniculitis using a newly established clinical disease activity index (Mesenteric Panniculitis Subjective Assessment Score). METHODS: In an open-label pilot study, five patients with symptomatic mesenteric panniculitis received oral thalidomide, 200 mg nightly, for 12 weeks. The primary end-point was a reduction in the Mesenteric Panniculitis Subjective Assessment Score by > or = 20% at 12 weeks or complete remission (absence of symptoms). RESULTS: Four (80%) of the five patients responded. The median Mesenteric Panniculitis Subjective Assessment Score at baseline was 39 and at week 12 was 25 (average decrease of 44%). One patient achieved complete remission by week 4, which was sustained. At 12 weeks, three (75%) patients experienced a global response, five (100%) patients had a > or = 20% (range, 29-98%) decrease in erythrocyte sedimentation rate and three (75%) patients had a > or = 20% (range, 61-93%) decrease in C-reactive protein. Abdomino-pelvic computed tomography scans were unchanged in all five patients. There were no serious adverse events. CONCLUSIONS: Thalidomide is safe, well tolerated and efficacious in the treatment of some patients with symptomatic mesenteric panniculitis. Further study is indicated. 相似文献
86.
Sialyltransferase ST3Gal-IV operates as a dominant modifier of hemostasis by concealing asialoglycoprotein receptor ligands
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Ellies LG Ditto D Levy GG Wahrenbrock M Ginsburg D Varki A Le DT Marth JD 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(15):10042-10047
A number of poorly characterized genetic modifiers contribute to the extensive variability of von Willebrand disease, the most prevalent bleeding disorder in humans. We find that a genetic lesion inactivating the murine ST3Gal-IV sialyltransferase causes a bleeding disorder associated with an autosomal dominant reduction in plasma von Willebrand factor (VWF) and an autosomal recessive thrombocytopenia. Although both ST3Gal-IV and ST6Gal-I sialyltransferases mask galactose linkages implicated as asialoglycoprotein receptor ligands, only ST3Gal-IV deficiency promotes asialoglycoprotein clearance mechanisms with a reduction in plasma levels of VWF and platelets. Exposed galactose on VWF was also found in a subpopulation of humans with abnormally low VWF levels. Oligosaccharide branch-specific sialylation by the ST3Gal-IV sialyltransferase is required to sustain the physiologic half-life of murine hemostatic components and may be an important modifier of plasma VWF level in humans. 相似文献
87.
Impact, diagnosis and treatment of von Willebrand disease 总被引:22,自引:0,他引:22
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