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排序方式: 共有428条查询结果,搜索用时 15 毫秒
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OBJECTIVE: To determine the possible use of the mammalian acrosomal marker vehicle-associated membrane protein (VAMP)/synaptobrevin to detect acrosome abnormalities in human sperm. DESIGN: Analysis of human sperm after fixation and staining with an anti-VAMP antibody. SETTING: An academic research institution. PATIENT(S): Semen samples from consenting patients who were participating in an infertility treatment program. INTERVENTION(S): Human sperm samples were fixed, permeabilized with detergent, and examined by immunocytochemistry. MAIN OUTCOME MEASURE: Immunostaining. RESULT(S): Observation of sperm from patients with no obvious sperm morphological defects revealed normal looking acrosomes, as assessed by VAMP immunostaining. However, severe acrosome malformations were detected in other cases. The observations registered varied from the absence of a fully formed organelle in samples of patients with globozoospermia to abnormal VAMP staining in samples from patients with acrosomal defects. CONCLUSION: VAMP/synaptobrevin may be a useful marker for the functional assessment of acrosomal status in human sperm. 相似文献
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Herpetic esophagitis 总被引:1,自引:0,他引:1
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We have extended previous observations to show that the ATPase N-ethyl maleimide sensitive factor (NSF) an important regulator of membrane trafficking and fusion in somatic cells, is present on bovine, murine and rhesus macaque sperm. However, NSFs main effectors, alfa- and beta-SNAP, although present in the developing acrosome, could not be detected in the mature organelle. The fact that NSF localizes mainly to the acrosome suggests that this protein, together with other factors such as rabs and SNAREs, may be a common feature in the triggering/regulation of membrane merging during the mammalian acrosome reaction. 相似文献
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Rhesus offspring produced by intracytoplasmic injection of testicular sperm and elongated spermatids
Hewitson L Martinovich C Simerly C Takahashi D Schatten G 《Fertility and sterility》2002,77(4):794-801
OBJECTIVE: To establish pregnancies in rhesus monkeys using testicular sperm and elongated spermatids injected into oocytes. DESIGN: Comparative animal study. SETTING: Regional Primate Research Center. ANIMAL(S): Prime, fertile rhesus monkeys. INTERVENTION(S): Oocytes collected by laparoscopy from gonadotropin-stimulated female rhesus monkeys were injected with testicular sperm or elongated spermatids obtained from the testis of males. Cleavage stage embryos were transferred to surrogate females. MAIN OUTCOME MEASURE(S): Fertilization, embryo cleavage, and the establishment of pregnancies. Fertilization failures were fixed and processed for the detection of microtubules and chromatin configurations. RESULT(S): Fertilization, assessed by the presence of two pronuclei within 15 hours after injection, was 60% for intracytoplasmic sperm injection with testicular sperm and 47% for elongated spermatid injection. Fertilized zygotes co-cultured in Connaughts Medical Research Labs (CMRL) medium on a Buffalo Rat Liver cell monolayer resulted in hatched blastocysts after testicular sperm extraction-intracytoplasmic sperm injection and elongated spermatids. Embryos transferred at the 4- to 8-cell stage gave rise to three pregnancies: 2/3 from testicular sperm and 1/1 from an elongated spermatid. Three healthy infants were delivered by cesarean. Oocytes that failed to fertilize typically remained arrested in metaphase of meiosis. CONCLUSION(S): Testicular sperm and elongated spermatids can be used for fertilization in the rhesus monkey resulting in live births. 相似文献
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Placental expression and serum levels of cytokeratin-18 are increased in women with preeclampsia 总被引:1,自引:0,他引:1
Hefler LA Tempfer CB Bancher-Todesca D Schatten C Husslein P Heinze G Gregg AR 《Journal of the Society for Gynecologic Investigation》2001,8(3):169-173
OBJECTIVE: To evaluate placental expression and serum cytokeratin-18 in women with preeclampsia. METHODS: Serum cytokeratin-18 was evaluated in 44 women with preeclampsia and 44 healthy pregnant women using an immunoradiometric assay. Placental expression of cytokeratin-18 was investigated in specimens from 23 women with preeclampsia and 20 healthy pregnant women by immunohistochemistry. RESULTS: Median serum cytokeratin-18 in women with preeclampsia and healthy pregnant women was 106.7 and 76.0 U/L, respectively (P =.02). Among women with preeclampsia, serum cytokeratin-18 was significantly associated with severity of disease (P =.001) and showed a sensitivity (standard error) and specificity (standard error) of 85% (7%) and 65% (12%), respectively. In placental specimens, the cytoplasm of the syncytiotrophoblast stained positive for cytokeratin-18 with strong and widespread staining in 83% and 45% of placental specimens of women with preeclampsia and healthy pregnant women, respectively (P =.01). CONCLUSION: Elevated serum cytokeratin-18 values are associated with disease severity in women with preeclampsia. Our data provide additional evidence that the placenta might be the source of the elevated serum cytokeratin-18 values in women with preeclampsia. 相似文献