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1.
2.
报道新化合物A-失碳-17β-羟基-17α-乙炔基-Δ3(5),9(10)-雌甾二烯-2-酮2的合成。文中探讨了用炔钾粗品对A-失碳-Δ3(5),9(10)-雌甾二烯-2,17-二酮1和A-失碳-6β,19-环氧-Δ3-雄甾-2,17-二酮3的选择性炔化,分别得标题化合物2(44%)及A-失碳-17β-羟基-17α-乙炔基-6β,19-环氧-Δ3雄甾-2-酮4(65%),4经还原性破开环氧、去羟甲基和去醋酰氧基合成了标题化合物2。四步总收率为34%。 相似文献
3.
The aim of the study was to determine the effect of exogenous melatonin treatment on circulating prolactin levels in red deer. Melatonin was administered from 12 June 1984 (day 1) to lactating and non-lactating hinds in the feed daily at 1600 h, and to non-lactating hinds by a subcutaneous implant. Average concentrations (ng/ml) of prolactin in plasma taken serially over 15-h periods were significantly higher for untreated hinds than for melatonin-treated animals on day 15 whether lactating (66-133 v. 23-28, P less than 0.05) or non-lactating (28-174 v. 8-13, P less than 0.01), remained higher on day 36 (lactating: 41-152 v. 15-21, P less than 0.05; non-lactating: 21-50 v. 1-7, P less than 0.001) but had decreased to similar levels on day 72 (lactating: 5-24 v. 7-17; non-lactating: 2-9 v. 0-4). The advanced reduction in plasma prolactin for all melatonin-treated hinds was associated with an advanced onset of seasonal breeding activity. 相似文献
4.
The Institute of Medicine distinguishes between programs based on who is targeted: the entire population (universal), those
at risk (selective), or persons exhibiting the early stages of use or related problem behavior (indicated). Evaluations suggest
that although universal programs can be effective in reducing and preventing substance use, selective and indicated programs
are both more effective and have greater cost-benefit ratios. This paper tests these assumptions by comparing the impact of
these program types in reducing and preventing substance use at the individual level (i.e., those exposed to intervention
services) and in the population (i.e., those exposed and not exposed to intervention services). A meta-analysis was performed
on 43 studies of 25 programs to examine program comparability across IOM categories. When examining unadjusted effect sizes
at the individual level, universal programs were modestly more successful in reducing tobacco use, but selective and indicated
programs were modestly more successful in reducing alcohol and marijuana use. When adjusted to the population level, the average
effect sizes for selective and indicated programs were reduced by approximately half. At the population level, universal programs
were more successful in reducing tobacco and marijuana use and selective and indicated programs were more successful in reducing
alcohol use. Editors’ Strategic Implications: The authors’ focus on the public health value of a prevention strategy is compelling and provides a model for analyses of
other strategies and content areas. 相似文献
5.
Occupational airborne allergic contact dermatitis from tylosin 总被引:2,自引:1,他引:1
6.
Cylindrical matrices were prepared by compression either of polyvinyl alcohol 100000 or mixtures of the excipient and a drug (sodium salicylate or theophylline). To modify the cylindrical shape, a hole was bored in the centre of the flat surface through both sides of the matrices. Different swellable systems were obtained applying an impermeable coating to one, two or three surfaces of the perforated matrices. The swelling of the perforated matrices was modified according to the number and the position of the coated surfaces (selective coating) and the loaded drug. Pseudo-zero order kinetics were obtained when the interior hole was the only uncoated surface. 相似文献
7.
选择性输卵管造影与再通术在诊治阻塞性不孕中的价值(附200例报告) 总被引:2,自引:1,他引:1
目的 :评价选择性输卵管插管造影 (SSG)及再通术 (FTR)在输卵管阻塞性不孕中的诊治价值。材料和方法 :先经宫颈对常规子宫、输卵管造影 (HSG)显示输卵管阻塞的 2 0 0例不孕妇女的 380条输卵管进行插管 ,采用选择性插管至输卵管开口处推注 76 %泛影葡胺造影 ,对证实阻塞者行导丝再通术 ,术后随访 2~ 4个月。结果 :插管成功率 99% ,无严重并发症 ,复通率 90 % ,妊娠率 2 1% (4 2 / 2 0 0 )。结论 :SSG和FTR是目前诊治输卵管阻塞性不孕的最好方法 相似文献
8.
Overview Excess spasticity leads to disability that is marked by impaired locomotion, handicapping deformities and, if not controlled,
discomfort and pain. Selective peripheral neurotomy in the child is indicated for severe focal spasticity, when botulinum
toxin injections cannot delay surgery any longer.
Materials and methods Preoperative motor blocks mimicking the outcome of the surgical procedure are essential to establish the objectives of neurotomy.
In the lower limb, obturator neurotomy is indicated for spasticity in the adductor muscles, hamstring neurotomy for the knee flexion and tibial
neurotomy for the spastic foot. Anterior tibial neurotomy is indicated for the extensor hallucis spasticity and femoral neurotomy
for spasticity in the quadriceps. In the upper limb, neurotomy of the pectoralis major and teres major nerves is indicated for spasticity of the internal rotators of the shoulder.
Neurotomy of the musculocutaneous nerve is indicated for spasticity of the flexors of the elbow, and neurotomy of median and
ulnar nerves are indicated for spasticity of the pronators and flexors of the wrist and fingers.
Conclusion Selective peripheral neurotomy is a valuable neurosurgical procedure in well-trained surgical hands for severe focalised spasticity. 相似文献
9.
Focal ischemia of the rat brain,with special reference to the influence of plasma glucose concentration 总被引:5,自引:0,他引:5
Summary Focal cerebral ischemia was induced by occlusion of the right middle cerebral artery in hypoglycemic, normoglycemic, as well as in acute and chronic diabetic rats. The brain damage was studied after 4 days. The volume of infarction was decreased in hypoglycemia (29±19 mm3 (mean±SD) versus 58±35 mm3,P<0.0046), unaltered in acute diabetes (61±45 mm3), and increased in chronic diabetes (91±22 mm3,P<0.0463). The cortex adjacent to the infarct showed selective neuronal injury affecting the cortical layers 2 and 3. The damage was enhanced by hypoglycemia and prevented in most of the diabetic animals. The findings indicate that different mechanisms cause infarction and selective neuronal injury outside infarcts, but that both are influenced by the plasma glucose concentration. 相似文献
10.