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71.
Population-based genetic associations have been reported between RFLPs detected with probes corresponding to the genes encoding the beta chain of the T-cell receptor for antigen (TCRB) and a variety of autoimmune disorders. In the case of multiple sclerosis (MS), these studies have localized a putative disease-associated gene to a region of approximately 110 kb in length, located within the TCRB locus. In the current study, all 14 known TCRBV (variable region) genes within the region of localization were mapped and identified. The nucleotide sequences of these genes were determined in a panel of six MS patients and six healthy controls, who were human-leukocyte antigen and TCRB-RFLP haplotype matched. Nine of the 14 TCRBV genes studied showed evidence of polymorphism. PCR-based assays for each of these polymorphic genes were developed, and allele and genotype frequencies were determined in a panel of DNA samples from 48 MS patients and 60 control individuals. No significant differences in allele, genotype, or phenotype frequencies were observed between the MS patients and controls for any of the 14 TCRBV-gene polymorphisms studied. In light of the extensive linkage disequilibrium across the region studied, the saturating numbers of polymorphisms examined, and the direct sequence analysis of all BV genes in the region, these results suggest that it is unlikely that germ-line polymorphism in the TCRBV locus makes a major contribution to MS susceptibility.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
72.
A. R. Carella C. Alonso J. C. Merino J. M. Pastor 《Polymer Engineering and Science》2002,42(11):2172-2181
A systematic approach was used to study the effect of the process variables that control bonding of the injected melt to the previously injected parts, in sequential injection molding of thermoplastic polymers. Three polymer pairs were sequentially injected in a mold with the same geometry, in a range of mold and injected melt temperatures, and packing pressure conditions. Standard Peel Tests were conducted on injected samples to measure the resulting bonding strength. The analysis of the experimental results allows the quantification of the relative importance of the processing parameters involved. A direct correlation is found between the calculated interface temperature and the packing pressure needed for bonding. A generalized procedure is proposed to establish the processing conditions, which allow polymerpolymer bonding to be optimized. 相似文献
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We report 18 patients who presented prior to age 20 years with epilepsy or fixed neurologic deficits. MRI showed signal abnormality extending from the cortex to the superolateral wall of the lateral ventricle. Histology showed cortical disorganization, neuronal cytomegaly, balloon cells, indistinct cortical gray matter-white matter junctions, and variable accompanying astrogliosis. We propose that this transmantle dysplasia is a specific anomaly resulting from abnormal stem cell development. 相似文献
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Overall ninety patients with chronic obstructive bronchitis presenting with signs of varying degree cardiopulmonary insufficiency (CPI) were evaluated by radionuclide ventriculography with technetium pertechnetate as well as by rotational viscosimetry of blood. The degree of hemorheological derangements tended to get higher with CPI severity (light, moderately severe, severe) being accompanied by progressing impairement of systolic and diastolic functions of both ventricles of the heart. Mechanisms of compensation of endocardiac hemodynamics were realized as a result of increase in end-diastolic and end-systolic volumes of both ventricles together with changes in amplitude and time characteristics of processes of ventricular ejection and filling. Forecast of the probable course of the condition may rely upon the functional state of right as well as left ventricle of the heart. 相似文献
77.
Previously, we demonstrated elevated cortisol production/release in response to the administration of the serotonin precursor, L-5-hydroxytryptophan (L-5-HTP) in untreated patients with obstructive sleep apnea (OSA). We hypothesized that if this elevated cortisol response to L-5-HTP was related to OSA, this finding would not be present in OSA patients treated with nasal continuous positive airway pressure (nCPAP). Eleven OSA patients treated for at least 1 month with nCPAP were studied. On two different days, we measured blood cortisol level every 15 min for 4 h following the ingestion of L-5-HTP, 0.4 mg/kg, or placebo, both given with carbidopa, a peripheral tryptophan decarboxylase inhibitor, used to prevent peripheral L-5-HTP metabolism before brain absorption. For a given subject, the cortisol response was calculated as the difference between the area under the curve of the L-5-HTP and placebo responses. In the nCPAP-treated OSA patients, this net cortisol response, 577 +/- 240 min.micrograms/dL, was less than the value found in the previously studied untreated OSA group, 1,198 +/- 227 min.micrograms/dL (p < 0.05) and not different from the previously studied nonapneic control group, 469 +/- 154 min.micrograms/dL. From these results, we speculate that nCPAP treatment reverses the elevated cortisol response to serotonergic stimulation seen in untreated OSA patients. 相似文献
78.
Operative treatment of fractures of the femur neck is the method of choice. The authors prefer the A. Seppo construction out of great number of fixtures but it is difficult to introduce and remove this fixture due to its complexity. To make the procedure of such interventions easier the authors propose a marking device, a screwdriver and a device allowing the fixture's curvature to be regulated. The modification of the technique and using a specially developed extractor is explained by difficulties in removing the fixture by common methods. The variant of the improved instrumental tooling proposed by the authors makes the operation more handy and practicable. 相似文献
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