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A patient with group B streptococcal endocarditis and large vegetations resembling mitral valve myxoma is described. Group B streptococcal endocarditis and the differential diagnosis of vegetations and cardiac tumors are briefly reviewed.  相似文献   
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Cham BE  Wilson L 《Planta medica》1987,53(1):59-62
Glycoalkaloids were extracted from plant material of SOLANUM SODOMAEUM L. High-performance liquid chromatographic studies indicated that several glycoalkaloids were present. The sugar moiety of the glycoalkaloids consisted of a mixture of glucose, rhamnose, and galactose. Mass spectral analyses showed that all the glycoalkaloids contained solasodine. Solasonine and solamargine were identified and were present at similar concentrations, representing 67% of the total extracted glycoalkaloids. The extraction yield of the glycoalkaloids from plant material, expressed as g glycoalkaloid/100 g wet weight, was highest for ripe fruit (0.83 +/- 0.11), followed by unripe fruit (0.45 +/- 0.08), leaves (0.14 +/- 0.01), and stems (< 0.04) with progressively decreasing yields. Over a twofold difference in glycoalkaloid yield was observed when ripe fruit of two different districts was extracted.  相似文献   
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Earlier studies in The Gambia suggested that the use of impregnated bednets might prove to be a useful malaria control strategy. Based on the results of these studies, in 1992 the Government of The Gambia was encouraged to initiate a National Impregnated Bednet Programme (NIBP) as part of the National Malaria Control Programme Strategy. This paper describes the implementation process/procedure of the NIBP. Evaluation results showed that, overall, 83% of the bednets surveyed has been impregnated, and 77% of children under the age of five years and 78% of women of childbearing age were reported to be sleeping under impregnated bednets.  相似文献   
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The reliability of auscultation, continuous wave (CW) Doppler imaging, and intravenous digital subtraction angiography (IV DSA) in the assessment of carotid artery disease has been evaluated in comparison with conventional angiography in 30 patients. With auscultation, specificity and sensitivity for internal carotid artery (ICA) stenosis of 50% or more were 81% and 67% respectively. CW Doppler imaging detected ICA stenosis of 50% or more with a sensitivity of 83% and a specificity of 92% and ICA occlusion with a sensitivity of 60%. The specificity of IV DSA was 95% and the sensitivity for ICA stenosis of 50% or more and ICA occlusion were 75% and 100% respectively. Combining CW Doppler and IV DSA findings raised sensitivity for ICA stenosis of 50% or more and ICA occlusion to 89% and 100% respectively and specificity to 95%. The combination of CW Doppler and IV DSA is a safe and accurate test battery in the detection and categorization of carotid disease.  相似文献   
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In areas of intense malaria parasite transmission, preliminary studies of the rate of reinfection after curative therapy suggest that small sample size studies of vaccine efficacy are feasible. However, the effect of transmission rate, which may vary considerably between transmission seasons, on reinfection rate has not been assessed in areas of mesoendemicity with seasonal transmission. To address this question, the Plasmodium falciparum reinfection rate after curative therapy was measured in Sotuba, a Malian village with historically low transmission rates, as estimated by the entomological inoculation rate (EIR). The reinfection rate after curative Fansidar (sulfadoxine-pyrimethamine) treatment was 80.7% (88/109). The EIR during the 13-week study period (seasonal transmission) varied between 1 and 4.5 infected bites/person/month. The finding that reinfection rates were high despite low EIRs suggests that a low EIR may be sufficient to support small sample size vaccine efficacy trials in mesoendemic areas.  相似文献   
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The study aim was to compare three formulations, tablet deltamethrin, liquid deltamethrin and liquid permethrin, for their impact on vector behaviour and persistence. Product acceptance, perceived side-effects and user's perceptions of effectiveness were also investigated. At the beginning of the 1998 rainy season, 255 nets in a Gambian village were dipped in one of the three insecticides. Chemical residue analysis immediately after dipping showed that the target doses were reached for the liquid insecticides, but tablet deltamethrin deposited significantly less. Insecticide persistence at 5 months, however, was highest for the tablet formulation. Susceptibility tests established that Anophelines in this area were sensitive to both insecticides. All three formulations appeared effective as very few live Anophelines, or other mosquitoes, were caught under the treated nets. This conclusion was supported by the bioassay data with both deltamethrin formulations giving over 90% mortality soon after dipping and at 3 months, and at 5 months 70.8 and 79.6% were obtained for deltametrin liquid and tablet, respectively. Permethrin appeared less effective at all times (72.4, 86.8, 59.0%). There were no serious side-effects reported by the villagers following dipping. All three treatments were perceived as effective by the majority (92%) of users and most (93%) wanted to use the insecticide again. Deltamethrin tablets thus appear as good as permethrin for treating bednets in The Gambia. In addition, a tablet formulation is considerable easier to pack and distribute.  相似文献   
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OBJECTIVES: To investigate the strengths and weaknesses of the indicators 'proportion of households possessing mosquito net(s)' and 'proportion of children under 5 years of age who slept under a net the preceding night' for monitoring malaria control. METHODS: Review of data from household surveys including demographic and health surveys in sub-Saharan African countries. RESULTS: Net possession ranged among 14 surveyed regions from 0.1% to 28.5% for insecticide-treated nets (ITNs) and among 69 regions from 3.6% to 79.7% for any net. Reported use during the preceding night by children under 5 years of age was between 0% and 16% for ITNs and between 0.7% and 74.5% for any net. On average, in households owning ITN(s), 55% of children slept under it (R2 = 0.97, P < 0.001). For any net, use was -4.2% + 0.875 x possession (R2 = 0.89, P < 0.001); the use of nets, however, also varied somewhat among the surveyed countries (P = 0.003). In-depth surveys suggested that use was lower than possession because: (i). nets were scarce (mean 1.8 per possessing household); (ii). nets were not always used for children and (iii). use was lower during hot, dry months than during cool rainy months, and many surveys had been conducted in the dry season. CONCLUSIONS: Not all mosquito nets owned by African households are being used for young children. Household education on the consistent use of nets for this vulnerable group is called for in malaria control programmes. Regular, district-level rapid assessments of household possession of nets should complement ongoing in-depth surveys. Data on 'use during the preceding night' must be interpreted taking the survey season into account.  相似文献   
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