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91.
The human leukocyte receptor complex (LRC) encompasses several sets of genes with a common evolutionary origin and which form a branch of the immunoglobulin superfamily (IgSF). Comparisons of LRC genes both within and between species calls for a high degree of plasticity. The drive for this unprecedented level of variation is not known, but it relates in part to interaction of several LRC products with polymorphic human leukocyte antigen (HLA) class I molecules. However, the range of other proposed ligands for LRC products indicates a dynamic set of receptors that have adapted to detect target molecules relating to numerous cellular pathways. Several receptors in the complex bind a molecular signature in collagenous ligands. Others detect a variety of motifs relating to pathogens in addition to cellular stress, attesting to the opportunistic versatility of LRC receptors.  相似文献   
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This study provides an overview of 10 years of experience of preimplantation genetic diagnosis (PGD) for cystic fibrosis (CF) in our center. Owing to the high allelic heterogeneity of CF transmembrane conductance regulator (CFTR) mutations in south of France, we have set up a powerful universal test based on haplotyping eight short tandem repeats (STR) markers together with the major mutation p.Phe508del. Of 142 couples requesting PGD for CF, 76 have been so far enrolled in the genetic work‐up, and 53 had 114 PGD cycles performed. Twenty‐nine cycles were canceled upon in vitro fertilization (IVF) treatment because of hyper‐ or hypostimulation. Of the remaining 85 cycles, a total of 493 embryos were biopsied and a genetic diagnosis was obtained in 463 (93.9%), of which 262 (without or with a single CF‐causing mutation) were transferable. Twenty‐eight clinical pregnancies were established, yielding a pregnancy rate per transfer of 30.8% in the group of seven couples with one member affected with CF, and 38.3% in the group of couples whose both members are carriers of a CF‐causing mutation [including six couples with congenital bilateral absence of the vas deferens (CBAVD)]. So far, 25 children were born free of CF and no misdiagnosis was recorded. Our test is applicable to 98% of couples at risk of transmitting CF.  相似文献   
94.
Risk perception in women with high risk pregnancies can affect their attitude to medical care and therefore influence the wellbeing of mother and baby. This article reviews quantitative measures of risk perception in women with high risk pregnancies. A systematic search of eight electronic databases was conducted. Additional articles were obtained through searching references of identified articles. Seven studies were identified that reported quantitative measures of risk perception in relation to high risk pregnancy. The main findings were that women with high risk pregnancies perceive themselves and the pregnancies to be at risk. However, mean risk scores consistently fall below the midpoint on risk perception measures suggesting women do not perceive this risk as extreme. Women with high risk pregnancies consistently rated their risk as being greater than that of women with low risk pregnancies. Results were inconsistent for the association between women's risk perception and that of healthcare professionals. Women with higher socio-economic status were more likely to be concerned about risk, although lower socio-economic status is associated with increased risk in pregnancy. There was a consistent association between high risk pregnancy and higher levels of anxiety. This review indicates that women at high risk during pregnancy do not perceive this risk to be extreme and that there is poor agreement between women's and healthcare professionals’ perceptions of risk. This is likely to have implications for medical care and pregnancy outcomes.  相似文献   
95.
The success of the iron (Fe) chelator desferrioxamine (DFO) in the treatment of beta-thalassemia is limited by its lack of bioavailability. The design and characterization of synthetic alternatives to DFO has attracted much scientific interest and has led to the discovery of orally active chelators that can remove pathological Fe deposits. However, chelators that access intracellular Fe pools can be toxic by either inhibiting Fe-containing enzymes or promoting Fe-mediated free radical damage. Interestingly, toxicity does not necessarily correlate with Fe-binding affinity or with chelation efficacy, suggesting that other factors may promote the cytopathic effects of chelators. In this review, we discuss the interactions of chelators and their Fe complexes with biomolecules that can lead to toxicity and tissue damage.  相似文献   
96.
An autoradiographic technique that employs 2-[14-C]deoxyglucose to measure the local rates of glucose utilization within the brain has been applied to the binocular visual system of the Macaque monkey. This method, which pictorially displays the relative rates of glucose consumption in the component structures of the brain, delineates the regions of altered functional activity because of the close relationship between functional activity and energy metabolism. Bilateral retinal stimulation results in the delineation of different rates of glucose consumption in at least four cytoarchitectural layers of the striate cortex. The most intense metabolic activity appears to be in Layer IV, the locus of the termination of the geniculocortical pathway. Bilateral visual occlusion lowers the rates of glucoes consumption in striate cortex and markedly reduces the metabolic differentiation of the various layers. Unilateral visual deprivation delineates the laminae of the lateral geniculate body and the ocular dominance columns of the striate cortex. It also results in the autoradiographic visualization of regions with normally monocular input in the striate cortex, such as the rostral portions of the mushroom-like configurations in the calcarine cortex, which represent the extreme temporal crescents of the visual fields, and small regions in the most caudal part of the mushroom configurations, which are believed to represent the cortical loci of the blind spotsof the visual fields.  相似文献   
97.
98.
The trends in and value and consequences of radiologic imaging in 1128 patients with perforated gastroduodenal ulcer have been studied over the 50-year period 1935–1985. The proportion of patients undergoing plain X-ray studies increased from 4% in the first 5-year period (1935–1939) to 94% in the last (1980–1985). Pneumoperitoneum was found in 77% of those undergoing X-ray studies. Water-soluble contrast studies were introduced in 1960, and in the three 5-year periods 1970–1985 from 8% to 13% underwent such imaging. Leakage was demonstrated in 60% of those undergoing contrast studies. Contrast studies have had a limited role in the pretreatment evaluation of these patients. The frequency of pneumoperitoneum was fairly constant over the 50-year period, and the only patient characteristic that influenced the occurrence of free gas in the abdominal cavity was age, with a higher proportion of patients with pneumoperitoneum in old patients. Any radiologic study increased treatment delay by at least 2 h.  相似文献   
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100.
Recertification offers a method of evaluating a diplomate's cognitive knowledge of allergy and immunology. In 1983 candidates for the American Board of Allergy and Immunology recertification examination were offered the entire certifying examination but were informed that they would, for recertification purposes, be held responsible only for a subset of questions judged to be particularly clinically relevant. All 40 candidates elected to take the entire certifying examination. Differences between the performance of certifying and recertifying candidates on the recertifying questions were small. Except for the five-choice questions, the differences in performance between the two groups on the remaining questions were also small in an absolute sense. Recertification performance was not related to the time of original certification. Ninety-eight percent of the candidates completed a questionnaire after the examination. Ninety percent stated that they would encourage their colleagues to participate in the recertification process.  相似文献   
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