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排序方式: 共有287条查询结果,搜索用时 12 毫秒
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Wanji S Kengne-Ouafo AJ Eyong EE Kimbi HK Tendongfor N Ndamukong-Nyanga JL Nana-Djeunga HC Bourguinat C Sofeu-Feugaing DD Charvet CL 《The American journal of tropical medicine and hygiene》2012,86(5):764-774
The present study analyzed the relationship between the genetic diversity of Plasmodium falciparum and parasitologic/entomologic indices in the Mount Cameroon region by using merozoite surface protein 1 as a genetic marker. Blood samples were collected from asymptomatic children from three altitude zones (high, intermediate, and low). Parasitologic and entomologic indices were determined by microscopy and landing catch mosquito collection/circumsporozoite protein-enzyme-linked immunosorbent assay, respectively. A total of 142 randomly selected P. falciparum-positive blood samples were genotyped by using a nested polymerase chain reaction-based technique. K-1 polymerase chain reaction products were also sequenced. As opposed to high altitude, the highest malaria prevalence (70.65%) and entomologic inoculation rate (2.43 infective/bites/night) were recorded at a low altitude site. Seven (18.91%), 22 (36.66%), and 19 (42.22%) samples from high, intermediate, and low altitudes, respectively, contained multiclonal infections. A new K-1 polymorphism was identified. This study shows a positive non-linear association between low/intermediate altitude (high malaria transmission) and an increase in P. falciparum merozoite surface protein 1 block 2 polymorphisms. 相似文献
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The authors describe a magnetic resonance imaging method for examination of the glenoid labrum of the shoulder joint that utilizes a radial fast-imaging sequence. Seven shoulders were examined: a total of five in three healthy asymptomatic volunteers, one in a symptomatic patient not suspected of having a lesion of the glenoid labrum, and one in a patient with recurrent shoulder dislocation and surgical proof of an extensive tear of the labrum. The preliminary results suggest that this technique may advantageously demonstrate pathologic changes in the glenoid labrum and may contribute to the evaluation of the unstable and painful shoulder. 相似文献
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冠状动脉狭窄的16层螺旋CT造影检查 总被引:3,自引:1,他引:3
目的以常规X线冠状动脉造影为标准,评价16层螺旋CT(MSCT)无创性检查冠状动脉及诊断冠状动脉狭窄的价值。资料与方法65例临床初诊为冠心病,无冠状动脉成形术和搭桥术史的患者,在冠状动脉16层MSCT造影检查后,回顾性重建心电门控轴位图像,并采用容积成像(VR)、多平面重建(MPR)、曲面MPR、最大密度投影(MIP)等后处理方法,对所有冠状动脉及其分支进行重建,统计可供临床评价的、管径≥1.5mm的冠状动脉段,以选择性冠状动脉造影(SCA)为标准,对比分析MSCT诊断冠状动脉显著性狭窄(管腔平均直径缩小超过50%)的准确性。其中8例在检查前心率超过80次/min的患者使用了B受体阻滞剂。结果93%的冠状动脉节段和94%的冠状动脉主干可供评价,不能评价的主要原因分别为:心脏运动伪影(58%),致密钙化(28%)和管腔显影不良(14%)。除外不能评价的冠状动脉,按节段和主干分类,MSCT诊断冠状动脉显著性狭窄的敏感性和特异性分别达到92%、98%和95%、97%。结论无需常规使用B受体阻滞剂,16层MSCT冠状动脉造影即可获得较好的图像质量用于诊断冠状动脉狭窄,是一种值得临床医师信赖的检查冠状动脉有无狭窄的非创伤性方法。 相似文献
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Measurements of T1 and T2 relaxation values and spin density of the lumbar vertebral bone marrow were performed in 212 patients, and the results were correlated with the patients' age and sex. T1 and T2 relaxation times for bone marrow in the lumbar vertebral bodies showed a progressive decrease with age for both sexes (except for the T2 relaxation values in female patients). The replacement of hematopoietic marrow by fatty marrow could explain the decrease in T1 and T2. The T1 and T2 values were in the same range for the first two age groups (age 1-10 years and age 21-40 years) and became slightly greater for the older female patients (age 51 years and older) than for the older males. This could be due to the loss of bone and mineral content, which is more rapid and significant for women. These normal T1 and T2 values may provide a baseline for future evaluation of diseases involving the lumbar spine. 相似文献
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Alzheimer’s disease(AD)is a neurodegenerative disease that is characterized by an age-dependent progressive decline of memory,impairment of cognitive functions and changes in personality and behavior.Despite the improvement in understanding of the mechanisms underlying the disease,AD remains an incurable complex disorder with multifaceted pathophysiology to date.Apolipoprotein E(ApoE)is the main cholesterol carrier in the brain that supports lipid transport between brain cells.The individuals carrying the APOE4 allele are known to be at increased risk of developing AD compared with those carrying the more common APOE3 allele. 相似文献
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Deficiency of platelet membrane glycoprotein Ia associated with a decreased platelet adhesion to subendothelium: a defect in platelet spreading 总被引:14,自引:5,他引:14
A bleeding disorder with absent collagen-induced platelet aggregation and adhesion has been described in a patient whose platelets failed to express surface glycoprotein Ia. We studied the interaction of her platelets with subendothelium in an annular perfusion chamber and the interaction with purified human collagen type III in a rectangular perfusion system under flow conditions. Platelet adherence was almost completely absent both at low and high shear rates. The few platelets which adhered remained in the contact stage without subsequent spreading and aggregate formation. Addition of a monoclonal antibody, which was directed against the von Willebrand moiety of FVIII-VWF, to the blood, completely abolished platelet adherence at high shear rates and had a partial effect at low shear rates. These data indicate that von Willebrand factor plays a role in the initial attachment (contact stage) of platelets to subendothelium. We conclude that the bleeding disorder and excessively prolonged bleeding time in our patient are caused by a new specific defect of the platelet-vessel wall interaction. 相似文献
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Simone SM Ho Winnie WM Yu Terence T Lao Daniel HK Chow Joanne WY Chung Yi Li 《Journal of clinical nursing》2009,18(11):1523-1532
Aims. This article aims to review the literature published to date on the types, current use, the biomechanical effects and adverse effects of maternity support belts for low back pain during pregnancy, to identify future research directions. Background. Lumbar/pelvic support belts are frequently recommended for the prevention and treatment of low back pain during pregnancy. Design. Systematic review. Methods. MEDLINE, CINAHL, the Cochrane Library and patents databases were electronically searched. Results. Maternity support belts belong to one of the four main types of maternity support garments, which are widely commercially‐available. Current research showed limited evidence in support of the commercial maternity products regarding the effectiveness in the prevention and/or treatment of low back pain during pregnancy, other than that from the manufacturers. However, potential stabilisation effect of maternity support belt was demonstrated in some studies. Adverse effects reported include increased pain, fetal heart rate changes, skin irritation and discomfort. Conclusions. There is insufficient scientific evidence to conclude that wearing maternity support belts reduces pregnancy‐related low back pain and/or pelvic girdle pain. Future research directions in the area of biomechanics and physiology are recommended. Relevance to clinical practice. This review provides comprehensive understanding of the effectiveness of maternity support belts for the relief of low back pain during pregnancy which will facilitate healthcare professionals in providing evidence‐based advice to their patients. 相似文献