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排序方式: 共有647条查询结果,搜索用时 15 毫秒
641.
642.
Rh E/e genotyping by allele-specific primer amplification 总被引:1,自引:0,他引:1
Faas BH; Simsek S; Bleeker PM; Overbeeke MA; Cuijpers HT; von dem Borne AE; van der Schoot CE 《Blood》1995,85(3):829-832
It has been shown that the Rhesus (Rh) blood group antigens are encoded by two homologous genes: the Rh D gene and the Rh CcEe gene. The Rh CcEe gene encodes different peptides: the Rh C, c, E, and e polypeptides. Only one nucleotide difference has been found between the alleles encoding the Rh E and the Rh e antigen polypeptides. It is a C-- >G transition at nucleotide position 676, which leads to an amino acid substitution from proline to alanine in the Rh e-carrying polypeptide. Here we present an allele-specific primer amplification (ASPA) method to determine the Rh E and Rh e genotypes. In one polymerase chain reaction, the sense primer had a 3'-end nucleotide specific for the cytosine at position 676 of the Rh E allele. In another reaction, a sense primer was used with a 3'-end nucleotide specific for the guanine at position 676 of the Rh e allele and the Rh D gene, whereas the antisense primer had a 3'-end nucleotide specific for the adenine at position 787 of the Rh CcEe gene. We tested DNA samples from 158 normal donors (including non-Caucasian donors and donors with rare Rh phenotypes) in these assays. There was full concordance with the results of serologic Rh E/e phenotyping. Thus, we may conclude that the ASPA approach leads to a simple and reliable method to determine the Rh E/e genotype. This can be useful in Rh E/e genotyping of fetuses and/or in cases in which no red blood cells are available for serotyping. Moreover, our results confirm the proposed association between the cytosine/guanine polymorphism at position 676 and the Rh E/e phenotype. 相似文献
643.
Busard MP Pieters-van den Bos IC Mijatovic V Van Kuijk C Bleeker MC van Waesberghe JH 《European journal of radiology》2012,81(6):1376-1380
Objective
Endometriosis infiltrating the bowel may be difficult to differentiate from colorectal carcinoma in cases that present with non-specific clinical and imaging features. The aim of this study is to assess the value of MR diffusion-weighted imaging (DWI) in differentiating endometriosis infiltrating the bowel from colorectal carcinoma.Methods
In 66 patients, MR DWI was added to the standard imaging protocol in patients visiting our outdoor MR clinic for the analysis of suspected or known deep infiltrating endometriosis (DIE). In patients diagnosed with DIE infiltrating the bowel on MR imaging, high b-value diffusion-weighted images were qualitatively assessed by two readers in consensus and compared to high b-value diffusion weighted images in 15 patients evaluated for colorectal carcinoma. In addition, ADC values of lesions were calculated, using b-values of 50, 400 and 800 s/mm2.Results
A total of 15 patients were diagnosed with DIE infiltrating the bowel on MR imaging. Endometriosis infiltrating the bowel showed low signal intensity on high b-value diffusion-weighted images in all patients, whereas colorectal carcinoma showed high signal intensity on high b-value diffusion-weighted images in all patients. Mean ADC value in endometriosis infiltrating the bowel (0.80 ± 0.06 × 10−3 mm2/s) was significantly lower compared to mean ADC value in colorectal carcinoma (0.86 ± 0.06 × 10−3 mm2/s), but with considerable overlap between ADC values.Conclusion
Only qualitative assessment of MR DWI may be valuable to facilitate differentiation between endometriosis infiltrating the bowel and colorectal carcinoma. 相似文献644.
Janssen BG Munters E Pieters N Smeets K Cox B Cuypers A Fierens F Penders J Vangronsveld J Gyselaers W Nawrot TS 《Environmental health perspectives》2012,120(9):1346-1352
Background: Studies emphasize the importance of particulate matter (PM) in the formation of reactive oxygen species and inflammation. We hypothesized that these processes can influence mitochondrial function of the placenta and fetus.Objective: We investigated the influence of PM10 exposure during pregnancy on the mitochondrial DNA content (mtDNA content) of the placenta and umbilical cord blood.Methods: DNA was extracted from placental tissue (n = 174) and umbilical cord leukocytes (n = 176). Relative mtDNA copy numbers (i.e., mtDNA content) were determined by real-time polymerase chain reaction. Multiple regression models were used to link mtDNA content and in utero exposure to PM10 over various time windows during pregnancy.Results: In multivariate-adjusted analysis, a 10-μg/m3 increase in PM10 exposure during the last month of pregnancy was associated with a 16.1% decrease [95% confidence interval (CI): -25.2, -6.0%, p = 0.003] in placental mtDNA content. The corresponding effect size for average PM10 exposure during the third trimester was 17.4% (95% CI: -31.8, -0.1%, p = 0.05). Furthermore, we found that each doubling in residential distance to major roads was associated with an increase in placental mtDNA content of 4.0% (95% CI: 0.4, 7.8%, p = 0.03). No association was found between cord blood mtDNA content and PM10 exposure.Conclusions: Prenatal PM10 exposure was associated with placental mitochondrial alterations, which may both reflect and intensify oxidative stress production. The potential health consequences of decreased placental mtDNA content in early life must be further elucidated. 相似文献
645.
Kgokong JL Matsabisa GM Smithand PP Breytenbach JC 《Medicinal chemistry (Shāriqah (United Arab Emirates))》2008,4(5):438-445
A series of N,N-bis(trifluoromethylquinolin-4-yl)- and N,N-bis[2,8-bis(trifluoromethyl)quinolin-4-yl] diamino alkane and piperazine derivatives were synthesised by employing a simple and rapid displacement reaction of the 4-chloro group on the 2-trifluoromethyl- and 2,8-bis(trifluoromethyl)-quinoline by diaminoalkane or piperazine groups. Results of in vitro antimalarial activity evaluations of these compounds against the chloroquine-sensitive (D10) and chloroquine-resistant (K1) strains of Plasmodium falciparum indicate that compounds with trifluoromethyl groups in both the 2 and 8 positions coupled with diaminoalkyl bridging chains of 2 to 6 carbon atoms exhibit a slightly higher activity than compound with only a trifluoromethyl group at position 2, and those with a piperazine bridge. These compounds exhibit higher activity in the chloroquine-resistant than in the chloroquine-sensitive strains of the Plasmodium. Comparative studies indicate that the compounds are more selective in their cytotoxicity against the parasite cells. Except for compounds containing a piperazine bridge, this new series of compounds interact with ferriprotoporphyrin IX to more or less the same extent. 相似文献
646.
Flow-mediated dilatation in the superficial femoral artery is nitric oxide mediated in humans 总被引:1,自引:0,他引:1
Kooijman M Thijssen DH de Groot PC Bleeker MW van Kuppevelt HJ Green DJ Rongen GA Smits P Hopman MT 《The Journal of physiology》2008,586(4):1137-1145
Flow-mediated dilatation (FMD) of the brachial and radial arteries is an important research tool for assessment of endothelial function in vivo , and is nitric oxide (NO) dependent. The leg skeletal muscle vascular bed is an important territory for studies in exercise physiology. However, the role of endothelial NO in the FMD response of lower limb arteries has never been investigated. The purpose of this study was to examine the contribution of NO to FMD in the superficial femoral artery in healthy subjects. Since physical inactivity may affect endothelial function, and therefore NO availability, spinal cord-injured (SCI) individuals were included as a model of extreme deconditioning. In eight healthy men (34 ± 13 years) and six SCI individuals (37 ± 10 years), the 5 min FMD response in the superficial femoral artery was assessed by echo-Doppler, both during infusion of saline and during infusion of the NO synthase blocker N G -monomethyl- l -arginine ( l -NMMA). In a subset of the controls ( n = 6), the 10 min FMD response was also examined using the same procedure. The 5 min FMD response in controls (4.2 ± 0.3%) was significantly diminished during l -NMMA infusion (1.0 ± 0.2%, P < 0.001). In SCI, l -NMMA also significantly decreased the FMD response (from 8.2 ± 0.4% during saline to 2.4 ± 0.5% during l -NMMA infusion). The hyperaemic flow response during the first 45 s after cuff deflation was lower in both groups during infusion of l -NMMA, but the effect of l -NMMA on FMD persisted in both groups after correction for the shear stress stimulus. The 10 min FMD was not affected by l -NMMA (saline: 5.4 ± 1.6%, l -NMMA: 5.6 ± 1.5%). Superficial femoral artery FMD in response to distal arterial occlusion for a period of 5 min is predominantly mediated by NO in healthy men and in the extremely deconditioned legs of SCI individuals. 相似文献
647.
Hilde van den Brink MSc Anna Kopczak MD Tine Arts PhD Laurien Onkenhout MD Jeroen C.W. Siero PhD Jaco J.M. Zwanenburg PhD Sandra Hein BSc Mathias Hübner MSc Benno Gesierich PhD Marco Duering MD Michael S. Stringer PhD Jeroen Hendrikse MD PhD Joanna M. Wardlaw MD Anne Joutel MD PhD Martin Dichgans MD Geert Jan Biessels MD PhD the SVDs@target group 《Annals of neurology》2023,93(1):29-39