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31.
The authors report trace elements concentrations (zinc, nickel, selenium, copper, manganese and chromium) during myocardial infarction described in some publication. Serum zinc decreases during the first two days after acute myocardial infarction and returns to normal level in two weeks. Serum nickel increases during the first 36 hours and copper during the first four days. The different explanations of these disturbances are also exposed.  相似文献   
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33.
The Premedical Honors College (PHC) is an eight-year, BS-MD program created in 1994 by Baylor College of Medicine (BCM) and The University of Texas-Pan American (UT-PA) to increase the number of physicians addressing the health care needs of underserved populations in Texas. The PHC targets South Texas, a 13-county, medically underserved area with a population that is 82% Hispanic. To date, the PHC has had 159 matriculants and 71 graduates, of whom 60 (84.5%) have matriculated into medical school. These results are significant considering that in 1996, only four students from all five South Texas colleges (combined enrollment of 30000 students) were accepted to medical school. An outcomes study comparing PHC matriculants with students of similar academic ability, ethnicity, and interest in medicine revealed that the odds of medical school matriculation were seven times higher for PHC students than for non-PHC students. The PHC's initial success has been acknowledged by the Texas legislature, which recently passed a bill to promote the PHC's replication. In addition, the number of PHC students-of whom 95% are Mexican American-who matriculate into medical school annually is significant nationally. In 2001, only 386 U.S. medical school matriculants (2.3% of all matriculants) were Mexican American; 17 of these students (4.4%) were PHC graduates. If current trends continue, the PHC could significantly expand the number of physicians serving minority and medically underserved populations in Texas and the nation. Also, the PHC provides an opportunity for research on programs designed to create pathways from high school to medical school.  相似文献   
34.
Mouse peritoneal cells (PC) in culture produce auto-antibodies lyzing bromelain-treated mouse erythrocytes (MRBCbr). These auto-antibodies have been obtained in an homogeneous form in substantial amounts after cell fusion of PC with myeloma X63.Ag8. They have been identified as the anti-Hb-auto-antibodies described by us in 1980. Once coupled to fluorescent microspheres (Ms), they were used to detect the corresponding antigen. It was found that the specific antigen was not only present on the surface of all MRBCbr but also, in a much smaller proportion, on some normal MRBC. Its distribution is not restricted to the mouse: pigeon RBC is stained heavily; human red cells give, more or less, positive reaction, according to their blood group. Some species, as horse RBC, are consistently negative. The opportunity offered by the fluorescent microspheres technique to trace the antigen recognized by the Hb-auto-antibody in the mouse tissues and on cells from other species should lead to a better understanding of the cross-antigenicity of many RBC and of the peculiar auto-immune process involving MRBCbr in the mouse.  相似文献   
35.
The authors review the keys parameters of flameless atomic absorption spectrometry trace element determination in biological medium. Contamination during sample collection and analysis are discussed. Treatments of sample are indicated. The different graphite furnaces are reviewed. Interferences and background correction are discussed. Reference samples are quoted.  相似文献   
36.
Health information in developing countries serves mostly to diseases notification and activity registration, but rarely is it used for analyzing the health status of populations or the results of health intervention. Moreover, it is stored at a national level, mainly to fill monthly or yearly reports, and very seldom at a peripheral level where it would be probably more helpful. On the basis of experiences realized in Senegal and Nepal, we try to answer the two following questions: how to make health statistics utilizable, i.e. which criteria of relevance and quality recommend and how to utilize them concretely where they are produced, taking into account their well known limits?  相似文献   
37.
Vitamin D3 and calcium to prevent hip fractures in the elderly women.   总被引:24,自引:0,他引:24  
BACKGROUND. Hypovitaminosis D and a low calcium intake contribute to increased parathyroid function in elderly persons. Calcium and vitamin D supplements reduce this secondary hyperparathyroidism, but whether such supplements reduce the risk of hip fractures among elderly people is not known. METHODS. We studied the effects of supplementation with vitamin D3 (cholecalciferol) and calcium on the frequency of hip fractures and other nonvertebral fractures, identified radiologically, in 3270 healthy ambulatory women (mean [+/- SD] age, 84 +/- 6 years). Each day for 18 months, 1634 women received tricalcium phosphate (containing 1.2 g of elemental calcium) and 20 micrograms (800 IU) of vitamin D3, and 1636 women received a double placebo. We measured serial serum parathyroid hormone and 25-hydroxyvitamin D (25(OH)D) concentrations in 142 women and determined the femoral bone mineral density at base line and after 18 months in 56 women. RESULTS. Among the women who completed the 18-month study, the number of hip fractures was 43 percent lower (P = 0.043) and the total number of nonvertebral fractures was 32 percent lower (P = 0.015) among the women treated with vitamin D3 and calcium than among those who received placebo. The results of analyses according to active treatment and according to intention to treat were similar. In the vitamin D3-calcium group, the mean serum parathyroid hormone concentration had decreased by 44 percent from the base-line value at 18 months (P < 0.001) and the serum 25(OH)D concentration had increased by 162 percent over the base-line value (P < 0.001). The bone density of the proximal femur increased 2.7 percent in the vitamin D3-calcium group and decreased 4.6 percent in the placebo group (P < 0.001). CONCLUSIONS. Supplementation with vitamin D3 and calcium reduces the risk of hip fractures and other nonvertebral fractures among elderly women.  相似文献   
38.
From 1979 to 1984, 8 cases of diphtheria were diagnosed in Basse-Terre, in children aged 11 months to 6 years. All of them were badly or not vaccinated at all. They showed the common clinical features; two patients had only pharyngitis. Corynebacterium diphtheriae was isolated from the throat in 6 patients. All children were successfully treated by early administration of antitoxin and antibiotics.  相似文献   
39.
Many cases of Lyme borreliosis have been reported over the years in the region of Lyon, France. The identification and prevalence of Borrelia burgdorferi sensu lato in Ixodes ricinus were investigated by polymerase chain reaction (PCR) of the flagellin gene and restriction fragment length polymorphism (RFLP) analysis. Questing Ixodes ricinus larvae, nymphs and adults were collected by the flagging method from deciduous forests in four areas in the Lyon region of France between October 1994 and September 1995 and in June 1998. The overall prevalence of Borrelia burgdorferi sensu lato was 13.2% (91/688). No significant differences in prevalence were observed between the different stages and sex of the ixodids or between collection areas. The majority of infections were simple infections (82.4%; 75/91), most of which were due to Borrelia afzelii (41.4%), while coinfections (12.1%) were predominantly (54.5%) a combination of Borrelia valaisiana and Borrelia garinii. No tick was infected with more than two borrelial species, nor was Borrelia lusitaniae identified. The Borrelia valaisiana species was detected for the first time in France, confirming its widespread presence in Europe. This study confirms that the surroundings of Lyon are risk areas for contracting Lyme disease and that no particular clinical manifestations predominate due to the heterogeneous distribution of Borrelia genospecies. Moreover, the polymerase chain reaction restriction fragment length polymorphism analysis is a rapid and easy method for genotyping of Borrelia species. Electronic Publication  相似文献   
40.
Laryngeal paraganglioma, carcinoid tumor, and small-cell carcinoma are rare. Histologically they are similar to analogous tumors in other locations but may be difficult to identify in small biopsy specimens. We compared the light microscopic, histochemical, immunohistochemical, and electron microscopic features of two laryngeal paragangliomas, one carcinoid tumor, and six small-cell carcinomas. The paraganglioma chief cells stained with Grimelius stain and for chromogranin and neuron-specific enolase. The carcinoid tumor cells stained with Grimelius stain and for chromogranin, serotonin, neuron-specific enolase, and keratin. The small-cell carcinoma cells stained for keratin and neuron-specific enolase. The patients with paragangliomas and carcinoid tumor remain healthy through 20 months of follow-up. Four of the patients with small-cell carcinomas have died. Distinction between these tumors is warranted by differing histologic appearances, staining characteristics, and biologic behavior.  相似文献   
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