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排序方式: 共有458条查询结果,搜索用时 171 毫秒
151.
目的:采用交流示波极谱滴定法测定了盐酸环丙沙星及其制剂的含量。方法:在pH5.0-5.5的醋酸-醋酸钠缓冲液溶液中,环丙沙星与四苯硼钠定量反应形成1:1沉淀。过量的四苯硼钠用醋酸亚铊标准溶液回滴至示波极谱图上四苯硼钠切口消失。结果:该法平均回收率为99.18%,RSD为0.49%。结论:本法简便,快速,结果准确,可靠。 相似文献
152.
In polycystic ovary syndrome (PCOS), increased luteinizing hormone (LH)
pulse frequency has been attributed to either the hypothalamic
gonadotrophin-releasing hormone (GnRH) pulse generator or ovarian oestrogen
feedback. To address this issue, a detailed examination of pulsatile LH
secretion was undertaken during recovery from GnRH agonist (GnRHa)
suppression. Each of six women with PCOS and six normal ovulatory women
received daily GnRHa treatment for 14 weeks. Frequent blood samples were
collected and assayed for gonadotrophins, androgens and oestrogens before,
during and up to 4 weeks after treatment. Women with PCOS had higher basal
LH pulse frequency and amplitude and increased serum concentrations of LH,
androstenedione, testosterone and oestrone than controls. After 3 months of
GnRHa treatment, all these parameters were suppressed with no differences
observed between the two groups. One week after cessation of GnRHa, LH
pulse frequency promptly returned to pre-treatment range with no
between-group differences noted, whereas LH pulse amplitude, serum
gonadotrophins and ovarian steroids remained maximally suppressed and
equivalent in the two groups. Subsequent LH pulse frequency remained
constant while LH pulse amplitude and circulating concentrations gradually
increased in parallel with a return of serum oestrogen to pre-treatment
values. Despite comparable resumption of LH secretion in the two groups,
corresponding androgen concentrations in women with PCOS were greater than
those of normal ovulatory women. Thus, the immediate restoration of LH
pulse frequency after discontinuing GnRHa treatment is largely independent
of ovarian oestrogen production and reflects primacy of the GnRH pulse
generator in determining basal LH pulse frequency. Equivalent LH pulse
frequency rates in the two groups during the recovery period do not suggest
an intrinsic hypothalamic-pituitary hyperactivity in PCOS.
相似文献
153.
马陆的抗炎药理研究初报 总被引:5,自引:0,他引:5
目的:实验研究开发具有抗炎效果好,来源丰富的动物药资源。方法:以马陆为研究对象,采用耳肿胀法、足跖肿胀法及测定其炎性渗出物含量等方法。结果:各项指标表明,马陆对实验动物的抗炎作用达到显著或极显著的效果。结论:马陆资源丰富,又有较强的抗炎作用,因此具有进一步研究开发的价值。 相似文献
154.
AP Baxter Dr PC Milner S Hawkins M Leaf C Simpson KV Wilson T Owen G Higginbottom J Nicholl N Cooper 《Public health》1997,111(4):231-237
A community health promotion project called Action Heart was undertaken in two electoral wards in Rotherham to try to change lifestyles of people. Schools were included within the project.Coronary heart disease lifestyle risk factors were measured at baseline and after a three year period in the intervention area and a similar control area. Lifestyle factors in schoolchildren were measured separately from adults using a different instrument.The post intervention survey of adults and economic evaluation demonstrated that Action Heart had achieved cost-effective estimated health gains. In the schoolchildren however, a mixture of positive and negative risk factor changes in both areas was demonstrated. Significant changes in lifestyle risk factors in schoolchildren were not elicited using this approach.The possible reasons for the lack of impact on lifestyle risk factors in schoolchildren are examined and the implications for further work explored. 相似文献
155.
156.
157.
A Wang MW Turner JF Soothill JO Warner AP Norman 《Archives of disease in childhood》1980,55(2):130-133
The factor in sera of patients with cystic fibrosis (CF) and their parents which agglutinates Proteus vulgaris has characteristics similar to those of IgG antibody to this organism. Sera of patients without CF who have P. vulgaris infections agglutinate the organism similarly. At present there are too many false-positives in a control population for the test to be widely useful for heterozygote identification. 相似文献
158.
159.
Area V4 in Cebus monkey: extent and visuotopic organization 总被引:2,自引:2,他引:0
We used electrophysiological mapping and myeloarchitectural criteria in
order to define the location, extent and visual topography of the fourth
visual area (V4) in anesthetized and paralyzed Cebus monkey. Based on these
criteria, the borders of V4 with surrounding areas were defined both on the
dorsal and ventral cortical surfaces. In addition, to better visualize the
visuotopic organization and to evaluate its regularity, we constructed
bidimensional maps and projected the recording sites onto them. Area V4 has
an almost complete representation of the binocular visual field with the
lower visual field represented dorsally (V4d) and the upper field ventrally
(V4v). We found this representation to be more extensive than those
previously described. The representation of the central portion of the
visual field is largely expanded in comparison with that of the periphery.
This emphasis in central vision could be related with the involvement of V4
in the ventral stream of visual information processing. Receptive field
size increases with increasing eccentricity, while cortical magnification
factor decreases. The cortical magnification factor measured along isopolar
lines is, on average, 1.5-2.0 times greater than that measured along the
isoeccentric lines, suggesting the existence of a small anisotropy in
central and peripheral V4.
相似文献
160.