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961.
A woman with Ullrich-Turner syndrome but with normal secondary sex characteristics became pregnant on two occasions (ages 23 and 24). She had a 45, X karyotype in 100/100 lymphocytes and 50/50 skin fibroblasts. The first pregnancy ended in a miscarriage at 2 months of gestation. In the second pregnancy cultured amniocytes showed a 46, X, del(X)(p21) karyotype. This pregnancy resulted in an apparently normal girl. Biopsies of the mother's ovaries were obtained at the time of cesarean section. Grossly the ovaries appeared normal, and histologically the number of primordial follicles appeared normal. In the right ovary, 5/100 cells were 46, X, del(X)(p21), while all 100 cells in the left ovary were 45, X.  相似文献   
962.
CT and MR evaluation of the brain in patients with anorexia nervosa.   总被引:5,自引:0,他引:5  
Thirteen adolescent girls with anorexia nervosa had MR imaging of the brain; 11 were also examined by CT. Fifteen children, ages 10-12 years, served as a control group. The CT and MR studies were evaluated qualitatively for cortical and central atrophic changes. CT detected sulcal and ventricular enlargement in 5/11 patients. On the MR images, enlarged sulci were seen in 10/13 and dilated ventricles in 5/13. In the anorectic patients, the range of the width of the third ventricle was 1-5 mm (mean, 3.2 mm) and the maximal distance between the anterior horns was 22.5-39.0 mm (mean, 30.0 mm). Anterior horns at their minimal width measured 11-30 mm (mean, 16.5 mm). The corresponding measurements in the control group were 1.5-3.5 mm (mean, 2.3 mm) for the third ventricle, 21-35 mm (mean, 28.5 mm) for the distance between the anterior horns, and 10-16 mm (mean, 12.8 mm) for their minimal width. Overall, the patient group had larger ventricles than the control group; however, the difference between the two groups was not significant. Measurement of the number of visible cortical sulci at one cut below the vertex yielded 2-11 sulci in the anorectic girls (mean, 6.6) versus 0-6 sulci (mean, 3.3) in the controls. These results are statistically significant (p = .0009), indicating peripheral volume loss in the anorectic patients. The MR examination did not reveal any additional structural or parenchymal changes when compared with the results of the CT studies. However, the pituitary glands of these patients did not have the expected normal pubertal hypertrophy on the MR examinations.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
963.
964.
Multi-unit ribozyme-mediated cleavage of bcr-abl mRNA in myeloid leukemias   总被引:1,自引:0,他引:1  
Leopold  LH; Shore  SK; Newkirk  TA; Reddy  RM; Reddy  EP 《Blood》1995,85(8):2162-2170
Chronic myelogenous leukemia is characterized by the Philadelphia chromosome, which at the molecular level results from the fusion of the bcr gene on chromosome 22 and the abl gene on chromosome 9. The bcr-abl fusion gene encodes a novel tyrosine kinase with transforming activity. In this study, we have synthesized a multi-unti ribozyme that targets bcr-abl mRNA. In vitro ribozyme cleavage reactions show increased cleavage efficiency of this multi-unit ribozyme compared with single or double ribozymes. The multiunit ribozyme was then transfected into murine myeloblasts transformed with the bcr-abl gene (32D cells). Ribozyme transfection was accomplished either by liposomes or using follic acid-polylysine as a carrier. Multi-unit ribozyme transfection reduced the level of bcr-abl mRNA 3 logs when transfected via folate receptor-mediated uptake into transformed 32D cells. These results suggest that a multi-unit ribozyme could be an effective therapeutic agent for the treatment of Philadelphia chromosome-positive chronic myelogenous leukemia.  相似文献   
965.
Plasma prolactin and cortisol levels after oral administration of d-l fenfluramine hydrochloride (60 mg) and placebo were examined in 24 endogenously depressed patients and 21 age- and sex-matched normal control subjects in a randomized, double-blind study. Prolactin levels were significantly increased by fenfluramine in both groups, but the response was significantly blunted in the depressed patients compared with the controls. This effect was partially dependent upon elevated baseline cortisol levels in the depressed group and was also influenced by a history of weight loss. Plasma cortisol levels were not increased by fenfluramine in either group. These findings confirm previous reports and suggest that patients with endogenous major depression are characterized by central serotonergic hyporesponsivity. The need to account for baseline effects on hormonal responses to putative serotonergic agents is supported by the findings; however, these effects appear to be less striking when endogenicity is a prominent clinical feature of the depressive syndrome. The apparently complex influence of weight loss on prolactin response to serotonergic challenge remains to be clarified as well as the role played by the bioavailability of the challenge drug and its metabolite.  相似文献   
966.
Genitourinary malacoplakia in renal transplant patients is rare. We report a case of malacoplakia of the bladder, which presented as a vesical tumor.  相似文献   
967.
968.
Abstract: We applied an erythrocyte adhesiveness/aggregation test (EAAT) to a model of plasma exchange in individuals with familial and primary hypercholesterolemia. The significant (p < 0.0001) reduction in the concentration of fibrinogen by 56%, globulins by 48%, and cholesterol by 53% corresponded to the expected significant (p < 0.0001) reduction in the degree of erythrocyte adhesiveness/aggregation in the peripheral venous blood. By virtue of its being a real‐time, simple, very‐low‐cost, and essentially bedside technique, the EAAT might have the potential of disclosing information of rheological relevance immediately before, during, as well as following apheretical procedures administered to patients with an impaired rheological profile.  相似文献   
969.
Abstract The natural history of changes in attachment level in the primary dentition should be determined before considering diagnostic criteria for periodontal diseases in children. The present study was designed to describe longitudinal changes in the distance between the alveolar bone crest and the cementoenamel junction (ABC-CEJ) determined radiographically. Bite-wing radiographs were obtained from 33 children as part of a routine annual dental examination in a rural community. The ABC-CEJ distance of 1500 sites located at the mesial and distal aspects of primary molars and distal aspect of primary cuspids were measured. An analysis of variance model was used to assess the effect of age, sex, tooth, side of the mouth, jaw, site and patient on the ABC-CEJ measurements. The side of the mouth (left, right) and the site (mesial, distal) had no significant effect on the ABC-CEJ distance. ABC-CEJ distances in the upper jaw were greater than in the lower jaw, and different teeth exhibited different ABC-CEJ distances. Canines had the greatest distance and second molars the smallest. The most interesting relationship was between alveolar bone height and age. The overall ABC-CEJ distance seemed to increase with age; however, this was not a linear relationship but followed the pattern of facial growth, with two spurts separated by a period of minimal increase. The results indicate that different levels of ABC-CEJ distance might be considered as a cut-off value for radiographic diagnosis of alveolar bone loss at different ages, for different primary teeth and for different jaws.  相似文献   
970.
The purpose of this paper was to describe our experience with the endovascular management of splenic artery pseudoaneurysms (SAPA). Seven patients with documented SAPA on CT and/or angiography were considered for endovascular treatment. The pseudoaneurysms were located in the main splenic artery (n = 4) or its branches (n = 3). In one patient in whom the pseudoaneurysm was located in a hilar branch, selective catheterization of splenic artery failed. Metallic coils (n = 1), gelfoam and hydrogel particles (n = 1), metallic coils and gelfoam (n = 2), metallic coil, gelfoam and acrylic glue (n = 2) were used as embolization material in the remaining six patients. These patients were followed for a mean period of 11.3 months. Transcatheter embolization was successful in five patients with no procedure‐related complications. In one patient, embolization was incomplete and the patient underwent surgery, but died on the 10th postoperative day because of irreversible shock. Another patient, after successful embolization, underwent surgery for management of an associated pseudocyst. Endovascular treatment is a safe and effective method of management of SAPA.  相似文献   
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