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81.
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Monitoring of maternal mortality levels in sub-Saharan Africa (SSA) to assess the achievements of safe motherhood programmes and for MDG-5 has been made difficult because of the lack of precise estimates of the maternal mortality ratio (MMR). Projections based on the slow rate of decline of the MMR indicate that MDG-5 may not be reached before the end of this century in this region. Measurements done using demographical and health surveys, statistical modelling and censuses are imprecise and do not allow trends in individual countries to be established. SSA countries should be encouraged to measure mortality levels from their own resources, using methods that produce precise estimates such as population-based surveys. Establishment of the trends will lead to country-specific program targets. The less frequent but more precise measurements can be afforded by SSA countries, as a case study from Zimbabwe shows.  相似文献   
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用体内外实验模型,研究了新维A类化合物4-乙酰胺苯基维A酸酯(4-APR)对肿瘤侵袭、转移的抑制作用。4-APR 43.3mg·kg-1po即能减少小鼠Lewis肺癌的自发性肺转移瘤数。半体内实验证明4-APR10-5mol·L-1和10-6mol·L-1对B16-F10癌细胞的人工肺转移瘤数分别抑制67.9%和36.6%。体外实验显示,4-APR对B16-F10细胞侵袭重组基底膜的抑制率分别为54.2%和41.9%。  相似文献   
85.
合欢皮中三萜皂甙元的研究   总被引:3,自引:0,他引:3  
陈四平  张如意 《药学学报》1997,32(2):144-147
合欢皮中三萜皂甙元的研究陈四平张如意(北京医科大学植化教研室,北京100083)中药合欢皮(Albizziaecortex)为合欢(AlbizziaejulibrisinDurazz)树皮。具解郁安神,活血消肿功能。用于心神不安,忧郁失眠,肺痈疮肿...  相似文献   
86.
1. Interactions between autacoids may play important roles in the regulation of blood flow in the foetal placenta. In order to investigate this aspect of placental haemodynamics, human normal-term placentae were perfused in vitro and the responses of the foetal vessels to various combinations of vasoactive agents were determined. 2. Vasoconstriction responses to 5-hydroxytryptamine (5-HT) were potentiated in the presence of endothelin-1 (ET-1), the thromboxane A2-mimetic U46619 and a nitric oxide synthase inhibitor, N-nitro-l -arginine (NOLA), but not in the presence of angiotensin II. 3. N-Nitro-l -arginine caused vasoconstriction of the perfused placenta and indomethacin attenuated this effect and blocked the potentiation of the 5-HT response by NOLA. 4. Indomethacin did not affect ET-1-induced pressure increases and infusion of U46619 had no effect on release of ET-Iike immunoreactivity into the foetal placental circulation. 5. The present study provides evidence of interactions between several autacoids in human perfused placentae in vitro. These interactions may play important roles in foetal placental haemodynamics in normal or pathological situations.  相似文献   
87.
Wavelength discrimination was studied on three colour-normal human observers for open viewing and for reduced time viewing. All three observers show a loss of blue-green wavelength discrimination when viewing time is reduced to 3.75 msec. This loss is shown to be an effect of viewing time alone and not of reduced retinal illuminance. The results confirm those reported by Foster, Scase and Taylor1 although the target size and methodology are different.  相似文献   
88.
Abstract: Some of the issues related to the doubts and complexities involved in the diagnosis and treatment of attention deficit hyperactivity disorder (ADHD) are reviewed. While some writers claim that it is clear that all children presenting with ADHD should be treated by pharmacological means, there are associated risks and politics. However, in the absence of well established and research-supported alternative understandings of the aetiology and treatment of the disorder, many practitioners feel unable to offer a useful service. Resulting frustrations have led some parents to form their own support networks, which make strong demands for increased services. More creative and innovative therapeutic interventions focusing on the broader impact of ADHD must be developed to deal with this disorder.  相似文献   
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