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101.
H. Schulman L. Saldana T. Tsai T. Leibman M. Cunningham G. Randolph 《Prostaglandins & other lipid mediators》1974,7(3):195-205
Prostaglandin E2, 20 mgm vaginal suppositories were administered to two groups of women seeking termination of pregnancy. One group had the suppository inserted inside a contraceptive diaphragm. Statistical comparisons were carried out for instillation to abortion time, side effects, and intra-uterine pressure parameters. The usage of the diaphragm significantly reduced side effects, and resulted in an instillation to abortion time of 12.8 ± 2.3 hours with no failures. The quantitative analysis of the uterine pressure recordings revealed activity significantly different than that seen with intra-amniotic or extra-ovular PG F2α. The development of uterine activity simulates that of normal labor in that elevation of resting pressure does not occur and maximum active pressure evolves slowly. 相似文献
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Preliminary results of a disjunctive procedure developed to ascertain the relative attractiveness for domestic chicks of auditory and visual stimuli are promising. A detailed account of the procedure and initial results is presented. Seventy-two Canadian Athens random bred chicks were tested at 24 or 36 h posthatch. A repetitive tone (4 per sec, 50 msec duration, 500 Hz) served as the auditory stimulus, and a flickering light (3.5 flashes per sec, 0.8 foot candle) served as the visual stimulus. An age-dependent change in the attractiveness of auditory and visual stimuli obtained with the disjunctive procedure. No change in stimulus preference obtained when the stimuli were presented individually. 相似文献
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Efficiently generating evidence of clinical utility is a major challenge for ensuring clinical adoption of valuable diagnostics. A new approach to reimbursement in the United States offers a balance between evidence and incentives for molecular diagnostic tests. 相似文献
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Retrotransposons can be used as markers because their integration creates new joints between genomic DNA and their conserved ends. To detect polymorphisms for retrotransposon insertion, marker systems generally rely on PCR amplification between these ends and some component of flanking genomic DNA. We have developed two methods, retrotransposon-microsatellite amplified polymorphism (REMAP) analysis and inter-retrotransposon amplified polymorphism (IRAP) analysis, that require neither restriction enzyme digestion nor ligation to generate the marker bands. The IRAP products are generated from two nearby retrotransposons using outward-facing primers. In REMAP, amplification between retrotransposons proximal to simple sequence repeats (microsatellites) produces the marker bands. Here, we describe protocols for the IRAP and REMAP techniques, including methods for PCR amplification with a single primer or with two primers and for agarose gel electrophoresis of the product using optimal electrophoresis buffers and conditions. This protocol can be completed in 1-2 d. 相似文献
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Active Ras-induced effects on skeletal myoblast differentiation and apoptosis are independent of constitutive PI3-kinase activity 总被引:2,自引:0,他引:2
23A2 myoblasts expressing GAP-resistant, constitutively active G12V:H-Ras (A2:G12V:H-Ras myoblasts) display a transformed morphology and do not undergo mitogen-deprivation-induced differentiation or the associated apoptosis. To determine the phenotype induced by F156L:H-Ras, a constitutively active mutant with enhanced nucleotide exchange activity rather than impaired GAP-stimulated GTPase activity, myoblast cell lines were established that stably express F156L:H-Ras at levels of H-Ras comparable to the A2:G12V:H-Ras myoblasts. These A2:F156L:H-Ras myoblast cell lines do not possess a transformed morphology, and while differentiation and apoptosis are impaired, these processes are not abrogated as in the A2:G12V:H-Ras myoblasts. Surprisingly, while expression of either G12V:H-Ras or F156L:H-Ras results in constitutive signaling through PI3-kinase, only cells expressing G12V:H-Ras additionally possess constitutive signaling through MAPK, and NFkappaB. Pharmacological abrogation of the Ras-induced constitutive PI3-kinase signal, however, is not responsible for the impaired differentiation or apoptosis in either A2:G12V:H-Ras myoblasts or A2:F156L:H-Ras myoblasts. Thus, our data suggest that a pathway distinct from those that signals through MAPK, NFkappaB or PI3-kinase is responsible for the impaired differentiation and apoptosis in 23A2 skeletal myoblasts expressing constitutively active Ras. 相似文献