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101.
BACKGROUND: In our center, childhood nephrotic syndrome (NS) had been reported for over a decade to be steroid sensitive contrary to reports in other parts of Nigeria. The purpose of this study was to determine if there are changes in presentation and response to steroids, with reviews of the literature on NS. METHODS: Analysis of 28 patients seen at the University of Port Harcourt Teaching Hospital, Nigeria, from 1999-2004 with the diagnosis of NS was performed. RESULTS: There were 14 girls and 14 boys with NS. The peak age was 1-4 years. Twenty (71.4%) children had idiopathic nephrotic syndrome (INS). Four had chronic renal failure, one had sickle cell disease (HbSS), two were positive to human immunodeficiency virus (HIV) 1 and 2, and one had pulmonary tuberculosis. Anemia was found in 13 patients, while 17 had Plasmodium falciparum. Plasmodium malariae and hepatitis-B surface antigen were not isolated. Renal biopsy was performed in four patients and revealed minimal-change disease in one child, focal segmental glomerulosclerosis in two and no conclusive result in one patient. Oral prednisolone was used in INS. After one month of therapy, 16 of 20 responded, of which 12 (75%) were <5 years. The NS relapsed in 15 of 16 steroid-sensitive patients. Cyclophosphamide and levamisole were used in four and one patients with FRNS, respectively. Four (14.3%) patients died; all were secondary NS. CONCLUSION: INS remains common in our center, and the majority respond to steroid therapy 相似文献
102.
Background
UK medical students and doctors from ethnic minorities underperform in undergraduate and postgraduate examinations. Although it is assumed that white (W) and non-white (NW) students enter medical school with similar qualifications, neither the qualifications of NW students, nor their educational background have been looked at in detail. This study uses two large-scale databases to examine the educational attainment of W and NW students.Methods
Attainment at GCSE and A level, and selection for medical school in relation to ethnicity, were analysed in two separate databases. The 10th cohort of the Youth Cohort Study provided data on 13,698 students taking GCSEs in 1999 in England and Wales, and their subsequent progression to A level. UCAS provided data for 1,484,650 applicants applying for admission to UK universities and colleges in 2003, 2004 and 2005, of whom 52,557 applied to medical school, and 23,443 were accepted.Results
NW students achieve lower grades at GCSE overall, although achievement at the highest grades was similar to that of W students. NW students have higher educational aspirations, being more likely to go on to take A levels, especially in science and particularly chemistry, despite relatively lower achievement at GCSE. As a result, NW students perform less well at A level than W students, and hence NW students applying to university also have lower A-level grades than W students, both generally, and for medical school applicants. NW medical school entrants have lower A level grades than W entrants, with an effect size of about -0.10.Conclusion
The effect size for the difference between white and non-white medical school entrants is about B0.10, which would mean that for a typical medical school examination there might be about 5 NW failures for each 4 W failures. However, this effect can only explain a portion of the overall effect size found in undergraduate and postgraduate examinations of about -0.32. 相似文献103.
Twenty-five patients with spontaneous or traumatic rupture of known renal cysts were encountered over an 18-year period. Blunt abdominal trauma and iatrogenic trauma during retrograde endoscopy accounted for four traumatic ruptures. In 21 patients, spontaneous communication occurred between the cyst and the collecting system or the perinephric space. Hematuria was the most frequent manifestation (21 patients [84%]), followed by flank pain (17 patients [68%]). The diagnosis was made by means of infusion nephrotomography in 22 patients, computed tomography in two, and retrograde pyelography in one. Follow-up information was obtained in 21 patients. The communication of the cyst with the collecting system closed spontaneously in 11 patients and persisted in two. Six patients were operated on because of coexisting stones, persistent hematuria, infection, or the uncertain nature of the cyst, and two underwent cyst evaluation by percutaneous needle aspiration. Renal cyst rupture is an infrequent, usually self-limiting event that may sometimes pose diagnostic dilemmas. 相似文献
104.
IC?McManusEmail author Sheeraz?Iqbal Amuthan?Chandrarajan E?Ferguson Joanna?Leaviss 《BMC medical education》2005,5(1):38
Background
Personal statements and referees' reports are widely used on medical school application forms, particularly in the UK, to assess the suitability of candidates for a career in medicine. However there are few studies which assess the validity of such information for predicting unhappiness or dissatisfaction with a career in medicine. Here we combine data from a long-term prospective study of medical student selection and training, with an experimental approach in which a large number of assessors used a paired comparison technique to predict outcome. 相似文献105.
106.
Sexual activity among 534 Nigerian female secondary school students was studied using self-administered questionnaire. Prevalence of sexual intercourse was 25.7%. There was no significant difference between the junior (48.2%) and senior (51.8%) students (p > 0.05). Seventeen (12.4%) students had initiated sexual intercourse before 11 years. The frequency of sexual exposure was high, with 34.3% of the students having intercourse more than once in a week. Pregnancy rate among sexually active females was 27.0%, with 24.8% rate of induced abortion. Early sexual health education starting from primary school would be helpful in influencing the reproductive decisions and sexual behaviour of the students, including contraceptive acceptance and usage, to avoid teenage pregnancy. Education of parents is also recommended in order to overcome the cultural barriers that discourage parents from providing sex education to their children at home. 相似文献
107.
Background
Malarial chemoprophylaxis is essential for patients with homozygous sickle cell disease (SCD) who live in areas where malaria is endemic. Endemic regions include most sub-Saharan African countries and Southeast Asia.Objective
This study compared the efficacy and tolerability of pyrimethamine with that of proguanil and placebo in the prevention of malaria and the complications of Plasmodium falciparum infection (hepatomegaly, splenomegaly, bone pain crisis, hemolytic crisis) in children with SCD.Methods
In this single-center, open-label study conducted in Nigeria, children aged 1 to 16 years with SCD were randomly assigned to receive tablets of pyrimethamine (0.5 mg/kg·wk), proguanil (1.5 mg/kg·d), or placebo (vitamin C, 7 mg/kg·d) for 9 months as prophylaxis from February to December (which includes the rainy season), the period of greatest malarial transmission. The clinical and laboratory features of malaria (presence of parasitemia, parasite count and density, hepatomegaly and/or splenomegaly, symptomatic malarial infection [fever, rigors], bone pain crises, and hemolytic crises) were assessed.Results
A total of 97 patients completed the study (49 boys, 48 girls; mean [SD] age, 7.8 [4.3] years). The pyrimethamine group comprised 36 patients (mean [SD] age, 8.1 [4.3] years; range, 2-16 years); the proguanil group, 32 patients (mean [SD] age, 9.5 [3.7] years; range, 3-16 years); and the placebo group, 29 patients (mean age, 5.9 years; range, 1-14 years). The male:female ratio was 1.1:1 in the pyrimethamine group, 1:1.7 in the proguanil group, and 1.6:1 in the placebo group. Parasitemia was noted in 7 patients (19.4%) in the pyrimethamine group, 6 (18.8%) in the proguanil group, and 7 (24.1%) in the placebo group at the start of the study. P falciparum was the only isolate. The mean parasite density over the 9-month period was significantly lower with proguanil compared with pyrimethamine (P = 0.045) and placebo (P<0.05). The incidence of splenomegaly was least with pyrimethamine, but this group had the most patients clinically diagnosed with malaria. Hospitalizations and episodes of bone pain and hemolytic crisis occurred most frequently with placebo. One patient in the placebo group died of septicemia.Conclusions
Proguanil and pyrimethamine both reduced parasitemia; however, proguanil significantly decreased mean parasite density more effectively than pyrimethamine. Pyrimethamine and proguanil may protect children with SCD from the complications of P falciparum infection despite persistent parasitemia. Proguanil may be more useful than pyrimethamine in the prevention of bone pain crises among patients with SCD. 相似文献108.
109.
Murdoch IA, Qureshi SA, Huggon IC. Perioperative haemodynamic effects of an intravenous infusion of calcium chloride in children following cardiac surgery. Acta Pzdiatr 1994;83:658–61. Stockholm. ISSN 0803–5253
Twelve children received an infusion of 10% calcium chloride 0.1 ml/kg to a maximum dose of 5 ml, infused over 5 min, following open heart surgery. Blood ionized calcium, systemic arterial pH, cardiac index, mean systemic arterial blood pressure and systemic vascular resistance index were measured at baseline and repeated 20 and 40 min following completion of the infusion. There was considerable overlap, with no significant differences in the response to the calcium chloride infusion between children with ionized hypocalcaemia (< 1.1 mmol/l) and those with ionized normocalcaemia when its effect on percentage change in either the haemodynamic or biochemical measurements was assessed ( p>0.2 for all measurements; Mann-Whitney). For this reason they were treated as a single group. Significant changes from baseline were noted in mean systemic arterial pressure (p 10.02), cardiac index (p<0.01) and systemic vascular resistance index (p<0.01) after completion of the calcium chloride infusion when analysed using Friedman's two-way analysis of variance. A significant increase in mean systemic arterial blood pressure occurs after an infusion of 10% calcium chloride as a direct result of an increase in the systemic vascular resistance index with a concomitant decrease in cardiac index. 相似文献
Twelve children received an infusion of 10% calcium chloride 0.1 ml/kg to a maximum dose of 5 ml, infused over 5 min, following open heart surgery. Blood ionized calcium, systemic arterial pH, cardiac index, mean systemic arterial blood pressure and systemic vascular resistance index were measured at baseline and repeated 20 and 40 min following completion of the infusion. There was considerable overlap, with no significant differences in the response to the calcium chloride infusion between children with ionized hypocalcaemia (< 1.1 mmol/l) and those with ionized normocalcaemia when its effect on percentage change in either the haemodynamic or biochemical measurements was assessed ( p>0.2 for all measurements; Mann-Whitney). For this reason they were treated as a single group. Significant changes from baseline were noted in mean systemic arterial pressure (p 10.02), cardiac index (p<0.01) and systemic vascular resistance index (p<0.01) after completion of the calcium chloride infusion when analysed using Friedman's two-way analysis of variance. A significant increase in mean systemic arterial blood pressure occurs after an infusion of 10% calcium chloride as a direct result of an increase in the systemic vascular resistance index with a concomitant decrease in cardiac index. 相似文献
110.
本文用消旋棉酚及其旋光异构体比较研究了对纯化小鼠肝脏LDH-A_4,心脏LDH-B_4和睾丸LDH-C_4的抑制作用。其抑制程度与实验温度和棉酚剂量有关。37℃时的抑制作用比25℃时强得多。棉酚低浓度(1~4μM)时三种酶对同一种棉酚的反应有明显的不同,而在较高棉酚浓度(20~100μM)时棉酚对三种酶的抑制作用大体相同。对同一种酶来说,消旋棉酚,右旋棉酚和左旋棉酚对LDH的抑制作用并无差异。结论是,棉酚及其旋光异构体并不特异地抑制LDH-C_4,而在离体试验中,不能反映棉酚在体内试验中所表现的光学立体结构特异性。 相似文献