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Etiological heterogeneity in Hodgkin's disease: HLA linked and unlinked determinants of susceptibility independent of histological concordance 总被引:2,自引:0,他引:2
Forty-one multiplex families, from published sources and new data from the National Cancer Institute, segregating for Hodgkin's disease and HLA, have been studied. A reanalysis of these data strongly suggests a recessive mode of inheritance for susceptibility to Hodgkin's disease. The HLA haplotype sharing data between affected relatives demonstrate that approximately 60% of cases in multiplex families are due to an HLA-linked susceptibility gene, the remaining 40% being due to other familial factors. The data clearly support the hypothesis of etiological heterogeneity for Hodgkin's disease, with both HLA-linked and HLA-unlinked factors being responsible. Finally, there is an increased concordance of histological types between affected relatives, but this concordance seems independent of HLA sharing. 相似文献
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Reto Treier Andreas Steingoetter Michael Fried Werner Schwizer Peter Boesiger 《Magnetic resonance in medicine》2007,57(3):568-576
Fast T(1) mapping techniques are a valuable means of quantitatively assessing the distribution and dynamics of intravenously or orally applied paramagnetic contrast agents (CAs) by noninvasive imaging. In this study a fast T(1) mapping technique based on the variable flip angle (VFA) approach was optimized for accurate T(1) quantification in abdominal contrast-enhanced (CE) MRI. Optimization methods were developed to maximize the signal-to-noise ratio (SNR) and ensure effective RF and gradient spoiling, as well as a steady state, for a defined T(1) range of 100-800 ms and a limited acquisition time. We corrected B(1) field inhomogeneities by performing an additional measurement using an optimized fast B(1) mapping technique. High-precision in vitro and abdominal in vivo T(1) maps were successfully generated at a voxel size of 2.8 x 2.8 x 15 mm(3) and a temporal resolution of 2.3 s per T(1) map on 1.5T and 3T MRI systems. The application of the proposed fast T(1) mapping technique in abdominal CE-MRI enables noninvasive quantification of abdominal tissue perfusion and vascular permeability, and offers the possibility of quantitatively assessing dilution, distribution, and mixing processes of labeled solutions or drugs in the gastrointestinal tract. 相似文献
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We used magnetic resonance imaging (MRI) to evaluate nine children with neurologic disorders caused by infections with members of the herpesvirus family. MRI studies were abnormal in eight children and demonstrated a wide range of central nervous system lesions, including cystic encephalomalacia, ventricular enlargement, cerebral atrophy and focal parenchymal lesions. When compared with conventional computed tomographic scanning, MRI was more sensitive in detecting abnormalities of white matter and in defining the extent of parenchymal lesions. These studies indicate that MRI scans are highly useful in children with herpesvirus infections involving the central nervous system. 相似文献
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J F Rouland T Amzallag F Bale 《Bulletin des sociétés d'ophtalmologie de France》1989,89(12):1425-1427
The case is described of a 36 years old woman with bilateral xerophthalmia secondary to his diet. She presented a perforation of the left cornea which required an emergency penetrating keratoplasty. The treatment is described. 相似文献
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Summary Development of third-stage larvae ofDipetalonema viteae within subcutaneously implanted micropore chambers proceeded in all hosts tested up to the fourth-stage larvae and occasionally to adolescent worms. In the jird the timing of development was comparable to a natural infection. Although the mouse is an insusceptible host, larval development could take place, but was very slow. Two intraperitoneal inoculations of living thirdstage larvae into mice induced the production of antibodies against the larval cuticle and against common antigens. In such immune mice the development of third- and fourth-stage larvae within micropore chambers was significantly inhibited, larval mortality was increased, and the larval motility was impaired. 相似文献
10.
Evidence against the practicality and cost-effectiveness of a gram-positive coccal selective plate for routine urine cultures.
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A total of 899 urine cultures were evaluated to assess the need for and cost-effectiveness of using a gram-positive coccal selective plate in the initial plating of urine cultures. Of these cultures, 437 were examined retrospectively and 462 were examined prospectively. Urines were quantitatively plated to three media: sheep blood sugar, MacConkey agar, and phenyl ethyl alcohol agar. Of all urine samples in both studies, 52% yielded no growth on any of the three media. Of all 899 urine cultures, there were only 5 cultures (less than 1%) in which a significant count of a gram-positive organism was detected only on the phenyl ethyl alcohol agar plate and not recoverable on the sheep blood agar plate. In each of these five instances, the need for the use of the selective plate occurred when a Proteus mirabilis strain swarmed over an enterococcus. The inclusion of a selective gram-positive coccal medium for initial plating of urine cultures is unnecessary and not cost-effective. When Proteus swarms on sheep blood agar, a sweep should be made with an inoculating loop from the sheep blood agar and streaked to phenyl ethyl alcohol agar or a similar gram-positive coccal selective medium. 相似文献