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991.
992.
993.
A modified technique for the repair of moderate to severe cicatricial entropion has been developed. This method is unique, as it involves the creation of a bipedicled tarsoconjunctival advancement flap. The technique avoids the causes of surgical failure seen with standard tarsal fracturing procedures. 相似文献
994.
With some, but not all, types and intensities of exercise, lactate accumulates in the blood and in the muscles engaged in the exercise. A great deal of attention has been directed towards attempting to understand the dynamics of lactate production and removal at the onset of exercise, during exercise, and during the recovery process following exercise. It has been hoped that an unravelling of these events would provide a key to understanding cellular metabolism and its regulation during exercise. The purpose of this introductory paper to a symposium on lactate is to present a brief overview of some of the conditions that influence the rate and magnitude of lactate accumulation during exercise. It is pointed out that many conditions influence the rate and magnitude of the accumulation of lactate in blood and muscles. Included are diet, state of physical fitness, and the type and duration of the exercise. We have cautioned against trying to evaluate the state of oxygen delivery to muscle and the state of tissue oxygenation from the appearance of lactate in blood. We have pointed out the positive aspects of lactate production based on how it augments the cellular supply of ATP, thereby allowing for high intensity exercise, and also the negative aspects that develop as a result the reduction in pH which adversely influences many cellular processes essential for muscular activity. 相似文献
995.
Antigen presentation by a B-cell line transfected with cloned immunoglobulin heavy- and light-chain genes specific for a defined hapten. 总被引:5,自引:1,他引:4
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M Watanabe D R Wegmann A Ochi N Hozumi 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(14):5247-5251
The rearranged genes encoding immunoglobulin heavy (mu) and light (kappa) chains specific for the hapten 2,4,6-trinitrophenyl (Tnp) were introduced into a B-lymphoma line that bears surface IgG with an unknown specificity and expresses surface Ia molecules. A transformant expressing surface IgM specific for Tnp was obtained. The transformant was found to present Tnp-proteins to antigen (protein)-specific T cells far more efficiently than the parenteral B-lymphoma line. This artificial system, utilizing recombinant DNA technology and gene transfer, provides several approaches for the study of T-cell-B-cell interactions. 相似文献
996.
997.
998.
Adenocarcinoma of the lower esophagus. A disease primarily of white men with Barrett's esophagus 总被引:3,自引:0,他引:3
E L Rogers S F Goldkind O A Iseri M Bustin L Goldkind S R Hamilton R L Smith 《Journal of clinical gastroenterology》1986,8(6):613-618
Sex and racial predilection, social history, and histology were analyzed in a biopsy-proven adenocarcinoma of the lower esophagus/esophagogastric junction collected over a 5-year period in two teaching institutions with different patient populations. Adenocarcinoma occurred in 11% of patients with biopsy-proven esophageal cancer. The disease occurred only in males at one center, and in a 7:1 ratio of males to females at the other center. Clear racial predilection was seen, since 12 of 13 patients with adenocarcinoma of the esophagus were white, whereas less than 20% of patients with squamous carcinoma of the esophagus were white. The finding of Barrett's epithelium in eight of the 13 cases strongly supports the theory that in white males, Barrett's epithelium is a precursor lesion of adenocarcinoma of the esophagus/esophagogastric junction. 相似文献
999.
Aseptic bone necrosis is a well known complication after corticosteroid treatment in adults and several hundred cases have been reported. Alterations in fat metabolism with vascular occlusion due to fat embolization, as well as microtraumata and osteoporosis are discussed as etiologic factors. In contrast, aseptic bone necrosis in relation to corticosteroid treatment is rare in children and adolescents. We therefore report 3 patients, aged from 10 to 18 years, suffering from severe aplastic anemia, meningeal relapse after acute lymphocytic leukemia and acute myelocytic leukemia respectively, who developed aseptic bone necrosis 6, 11, and 20 months following the onset of corticoid therapy. The patients survive from 28+ to 50+ months after diagnosis of their initial hematologic disease, as it can be expected today for increasing numbers of patients. We therefore believe, that aseptic bone necrosis may represent a serious therapy related complication and suggest that, diagnostic examination in patients with suspicious complaints of the hip, shoulder or knee should also exclude the possibility of a bone necrosis after leucemic relapse has been ruled out. Since radiological changes only develop several weeks to months after the onset of the clinical symptoms and because of the disabling consequences for patients, misdiagnosed at the beginning, a 99 technetium bone scan should be done as early as possible. Corticosteroids, despite their serious side effects are still being considered as a important part of hematologic therapy and are not being omitted in the near future, so that the earliest possible diagnosis of bone necrosis will remain of great importance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.
Contact lens-induced corneal warpage 总被引:1,自引:0,他引:1