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Background  

The objective of this study was to examine missed opportunities for participation in a prevention of mother-to-child transmission (PMTCT) programme in three sites in South Africa. A rapid anthropological assessment was used to collect in-depth data from 58 HIV-positive women who were enrolled in a larger cohort study to assess mother-to-child HIV transmission. Semi-structured interviews were conducted with the women in order to gain an understanding of their experiences of antenatal care and to identify missed opportunities for participation in PMTCT.  相似文献   
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The interaction of fluoxetine, a non-tricyclic antidepressant, with the human placental serotonin transporter was investigated by studying its influence on [3H]paroxetine binding to the transporter and on [3H]serotonin uptake via the transporter. These studies were done using brush-border membrane vesicles purified from normal term human placentas. Fluoxetine inhibited binding of paroxetine to the membrane vesicles in a concentration-dependent manner, with a Ki value of 3 nM. Kinetic analysis revealed that the inhibition was competitive because the presence of 10 nM fluoxetine increased the Kd for paroxetine from 72 to 461 pM, but had no effect on the Bmax. Fluoxetine also caused a time-dependent dissociation of paroxetine already bound to the transporter. The dissociation followed first-order kinetics. Uptake of serotonin in these membrane vesicles was also inhibited by fluoxetine. The inhibition was concentration dependent with a Ki value of 66 nM at pH 7.5 and 80 nM at pH 6.5. The effect of fluoxetine on the uptake kinetics was to increase the apparent dissociation constant (Kt) for serotonin without influencing the maximal transport capacity (Vmax). The results demonstrate that fluoxetine is a high-affinity ligand and a potent inhibitor of the serotonin transporter found in the human placental brush-border membrane.  相似文献   
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The effectiveness of periocular anaesthesia and its complications were examined in 100 successive cataract operations. The patients were divided into 3 groups according to the duration of ocular compression with an Autopressor device after administration of periocular anaesthesia. In the control group, no compression was used (C-O, n = 36 patients). In the other two groups, compression was used for 10 (C-10, n = 32) and for 20 (C-20, n = 32) min. No differences in globe or orbicular akinesia were found between the groups. At 10 min, immobilisation of the globe in different directions was attained in 60.1-84.5% of the patients. Compression for an additional 10 min did not significantly improve the akinesia. In contrast, the hitherto undescribed loss of light perception increased with time: 15 patients at 10 min and 22 at 20 min were unable to see light. Chemosis and haematomas in the upper eyelid occurred more often in C-0 than in the other 2 groups. One day postoperatively the average palpebral aperture was smaller in C-0 than in the other two groups. The frequent postoperative ptosis (74.3% on the 1st day) decreased rapidly, but on postoperative day 7, 9 patients still had ptosis. In only one patient was ptosis still recognizable at 6 weeks postoperatively. No serious complications occurred. This study demonstrates that periocular anaesthesia with ocular compression is a suitable method for cataract surgery.  相似文献   
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Snellen letter and Vistech sine wave grating charts were used as refraction targets to determine differences in times required to accomplish subjective refractions, endpoint refractive values, and subject preferences. Thirty hyperopes and 30 myopes, divided into three age groups, were selected as subjects. Two examiners tested each subject using each chart. Both timed their subjective refractions and recorded their findings. After all data were recorded, each subject completed a questionnaire to determine chart preference. There were no clinically significant mean differences between the charts in terms of endpoint refractive data, but, on average, the Snellen chart was faster to use. Chart rating depended on the subject's refractive status with more myopes preferring the Snellen chart and more hyperopes rating the grating chart higher.  相似文献   
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General practitioners' (GPs') advice against smoking helps smokers to stop; unfortunately, GPs cannot predict which patients will quit following advice. This postal questionnaire survey suggests that where smokers attribute their respiratory symptoms to smoking, they are eight times (95% confidence interval [CI] = 3.0-23.3) more likely to believe that their health will improve if they stop smoking and six times (95% CI = 1.4-23.3) more likely to intend to stop smoking.  相似文献   
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