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91.
92.
Ten years have now passed since the College of Medicine of the University of Malawi was opened. The College''s Curriculum is firmly based on community needs. We describe the genesis and implementation of the curriculum of the College of Medicine and how it has persisted over the past ten years. The challenges that have so far been met are outlined.  相似文献   
93.
Five isolates of Cryptosporidium parvum collected from human, horse, and calf sources were compared for differences in sporozoite protein patterns by using two-dimensional gel electrophoresis. Silver-stained two-dimensional gels contained over 300 protein spots from detergent-solubilized sporozoites. A distinguishing 106-kilodalton peptide that shifted in isoelectric point was detected in four of the five isolates. Computerized two-dimensional gel analysis was performed to obtain objective quantitation of the pI shift. Three of these four isolates could be differentiated from one other by the pI shift in this peptide. The fifth isolate was distinguished by the absence of the 106-kilodalton peptide and the presence of a 40-kilodalton peptide that was not observed in any other isolate.  相似文献   
94.
We have studied serum immunoreactive erythropoietin (SIE) levels in 28 patients with sickle cell anemia (SCA) without renal insufficiency and in 17 patients with nonhemoglobinopathy anemias of comparable severity using a sensitive radioimmunoassay procedure. An exponential relationship between SIE level and degree of anemia was noted in all patients. However, in nonhemoglobinopathy anemia, a sharp rise in the SIE level occurred as hemoglobin (Hb) levels fell below about 12 g/dL, whereas in sickle cell patients the increase was not marked until hemoglobin fell to about 9 g/dL. The response was more blunted in older SCA patients than in younger ones. A linear regression model relating SIE level to Hb level, presence/absence of SCA, and age explained 63% of the variation in SIE. We conclude that the serum erythropoietin levels in SCA increased at a lower hemoglobin concentration and are of a lower magnitude than that of the other anemias.  相似文献   
95.
Splenic lymphangiomatosis in children   总被引:14,自引:0,他引:14  
  相似文献   
96.
Kenney  RT; Malech  HL; Epstein  ND; Roberts  RL; Leto  TL 《Blood》1993,82(12):3739-3744
The genetic defect in the p67phox-deficient form of chronic granulomatous disease (CGD) follows an autosomal recessive pattern of inheritance. When genomic DNA from normal individuals is digested with HindIII and probed with p67phox cDNA an allelic restriction fragment length polymorphism (RFLP) of 4.0 kb or 2.3 kb is detected. We cloned and characterized the p67phox gene using the cDNA and sequenced the exon/intron boundaries, mapping 16 exons on the 40-kb gene. The polymorphic region was then sequenced to identify the inheritance pattern of amniocentesis-derived fetal cells by genomic amplification. The proband, a 9-year-old female patient with p67phox-deficient CGD, and her phenotypically normal mother are homozygous for the RFLP marker, whereas the father and two brothers are heterozygous. The fetus was shown to be heterozygous as well, showing it had inherited at least one normal p67phox gene from the father and that it was predicted to have a normal phenotype. Cord blood samples at birth showed normal oxidative function. Amplification allows rapid detection of the inheritance pattern for fetal diagnosis in informative families. We report the genomic structure of p67phox and an amplification-based method for detection of the marker on chromosome 1q25, used here for prenatal diagnosis of CGD.  相似文献   
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99.
Purpose: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. Methods: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4–6 months and glaucoma suspects every 1–2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. Results: It was found that during the period under review, 7.4% (n= 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P= 0.0001) followed by 11.4% of primary open-angle glaucoma eyes (P= 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. Conclusions: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance.  相似文献   
100.
目的:调查重庆居民及流动人口结核病就诊及诊断延迟情况,探索在其过程中存在的问题,分析问题产生的原因。方法:在重庆市主城区按照经济发展水平的不同选取了两个区Y和J,采用方便抽样的方法在Y区抽取了一家综合性医院的呼吸科门诊R,在J区抽取了一家综合性医院的一般基层门诊P,于2005-10-10/14和2005-10-17/21,采用隐蔽性观察法对门诊情况进行了观察,主要观察医生和患者的相关语言、行为,了解结核病就诊及诊断延迟情况。实验得到了利物浦大学热带医学院伦理委员会的许可,并通过了重庆市卫生局的批准。资料分析采用主题框架分析法。结果:重庆居民和流动人口都存在结核病就诊延迟的情况,主要与患者的经济状况、健康意识和社会支持等因素有关;医院在结核病的诊断方面具备基本的技术和条件,诊断延迟则主要与医务人员对结核病的意识和责任心有关;另外患者自身在诊疗过程中的中途退出现象不容忽视,也是导致延迟的一个重要因素。结论:一方面综合医院缺乏对结核病患者的管理措施和意识,对结核患者重治轻管,另一方面特殊人群的患者卫生保健支付能力差,缺乏相关结核病防控知识,应依据目前的形势对相关领域进行政策倾斜和调控,积极开展对人群行之有效的健康教育。  相似文献   
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