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41.
Data on the occurrence of neural tube defects in first-, second-, and third-degree relatives of probands were collected in a United States study. The proportions of affected individuals were 3.2%, 0.5%, and 0.17% respectively. These findings are compared to those from other recent North American studies, and differences are discussed. It is pointed out that accurate recurrence risk figures may not be available, and that caution should be used when counseling families with relatives who are affected with NTD.  相似文献   
42.
Summary.  Primer extension analysis was used to determine the presence of RNAs 4A and 5 in tomato aspermy virus (TAV) and both subgroups of cucumber mosaic virus (CMV). RNAs 4A and 5 were detected in TAV and all CMV strains (representative of both subgroups) that were analysed, except for one subgroup I CMV strain which lacked detectable RNA 5. In subgroup II CMV strains the RNA 5 population was found to consist of two sequence variants. Comparison of the RNA 5 sequences from TAV and CMV indicated that TAV and subgroup II CMV RNA 5 share a much greater degree of sequence similarity than either has with subgroup I RNA 5. RNA 4A and the encoded 2b protein appear to be unique to the cucumovirus genus of the tripartite viruses, which share an otherwise common genome structure, and may have played a role in the evolutionary origin of this genus. Accepted November 15, 1996 Received May 27, 1996  相似文献   
43.
We report 2 cases of B-cell lymphoma of the thyroid in which although a marginal zone distribution of the neoplastic cells was present, the cytologic features of the cells indicated large cell lymphoma. One of the cases showed an accumulation of crystalline inclusions within the cytoplasm of the neoplastic cells. Many of these inclusion-bearing cells showed plasmacytoid features. By immunohistochemical studies performed on formalin-fixed paraffin-embedded tissue, both of the cases showed a B-cell phenotype as indicated by CD20 expression, and 1 showed kappa light chain restriction. In both cases, Ki-67 staining corroborated the impression of an aggressive neoplasm with staining of 50% and 90% of the tumor cells. Both patients received cyclophosphamide, doxorubicin, vincristine, and prednisone with radiation therapy, and both are without evidence of disease after 17 and 18 months of follow-up. It is important to recognize this pattern of large B-cell lymphoma of the thyroid gland. While the indolent course typical of most low-grade extranodal marginal zone lymphomas is not likely in these cases, the outcome may be favorable if patients are treated aggressively with therapy for large cell lymphoma.  相似文献   
44.
The purpose of the present study was to determine the frequency in which antibody reactive to Ureaplasma urealyticum could be detected in a population of pregnant women and newborn infants. Serum samples from a prospective cohort of 80 healthy, U. urealyticum culture-positive and culture-negative pregnant women and a retrospective cohort of 522 infants born at between 25 and 42 weeks of gestation were studied by immunoblot analysis. Cultures of specimens from the lower genital tract were positive for U. urealyticum for 83% of the pregnant women, and serum immunoglobulin G (IgG) antibody which reacted to U. urealyticum was detectable in 93% of the pregnant women. Samples from five women (8%) had increases in the number of anti-U. urealyticum IgG bands over the course of the pregnancy. Samples from four of these five women had corresponding increases in the number of antibody bands present in IgA immunoblots. Six of the 522 samples from newborns or cord blood (1.1%) were positive for anti-U. urealyticum IgA; 5 of these 6 samples were also positive for IgM. The six anti-U. urealyticum IgA-positive infants were distributed as follows; 3 of 67 (4.5%) infants were delivered at 25 to 30 weeks of gestation, 3 of 176 (1.7%) infants were delivered at 31 to 34 weeks of gestation, and 0 of 279 infants were delivered at > or = 35 weeks of gestation. An antibody response to U. urealyticum can be detected in pregnant women and preterm infants and may serve as a marker of infection.  相似文献   
45.
46.
Allogeneic and congenic post-irradiation chimeras were produced by bone marrow transfer from C′5 active donor mice into C′5 defective recipients. During the first 4 weeks after transfer many of the chimeras contained haemolytic complement activity in their sera. B6AF1→A chimeras developed higher levels of activity than did B10D2 (new line)→ B10D2 (old line).

Spleen tissue, but not liver tissue, taken from the chimeric animals during this time period incorporated [14C]amino acid into MuB1 as demonstrated by autoradiography of immunoelectrophoretic patterns, suggesting localization of the active donor cells in the spleen rather than in the liver. Formation of donor-type IgG remained demonstrable for a more extended period after induction of chimerism than formation of MuB1.

A transplantable hepatoma in C57L/J, a C′5 active mouse strain, also incorporated [14C]amino acid into MuB1.

  相似文献   
47.
This study examined two groups of people who were pursuing treatment for obesity: either medical intervention (a hospital group; N = 20) or support for dietary restriction (a community group; N = 18). This study addressed four questions: (1) Were there differences between the two groups in terms of their psychological distress (as measured by the Symptom Checklist)? (2) Does binge eating moderate psychological distress? (3) Do feelings of ineffectiveness moderate psychological distress? and (4) Which variables best accounted for group membership (i.e., type of treatment sought)? Results suggested that the hospital group was significantly more distressed than the community group. However, there were no differences between the two groups with respect to binge eating or feelings of ineffectiveness. These findings suggest that it is the effects of morbid obesity that are most likely to moderate psychological distress.  相似文献   
48.
Native horseradish peroxidase (HRP) is known to pass rapidly through glomeruli when injected into rats. We have found that a conjugate of HRP with poly-lysine is readily endocytosed by glomerular epithelial cells (GEC). We have used this conjugate to study the GEC endocytotic process in male Wistar rats. The conjugate has an approximate molecular weight of 55-58,000, a pI of greater than 10.0, and almost the same secondary conformation as HRP; it does not increase urinary protein excretion significantly or alter the morphology of the renal glomeruli. After intravenous injection of the conjugate, it could be found in the GBM from 1 min to 4 h. At 1 min, it was evenly distributed on GEC foot processes and plasma membrane. GEC start to take up the conjugate from 1 min post-injection, by cellular membrane invagination. This reached a maximum at 4 h. Some of the endocytosed conjugate passed to lysosomes from the endosomal system. The amount of peroxidase demonstrable in the glomerular epithelial cells was considerably reduced by 24 h.  相似文献   
49.
Brother were affected with severe congenital contractures, multiple cutaneous manifestations of ectodermal dysplasia, cleft lip/palate, and psychomotor and growth impairment. High resolution prometaphase chromosomes were normal. Molecular studies of DNA markers, closely flanking the X-linked hypohidrotic ectodermal dysplasia locus, did not show evidence of a submicroscopic deletion from the Xq12-q13 region. The parents and a normal sister exhibited none of these findings. This constellation of anomalies appears to represent a unique AR or XLR syndrome. © 1993 Wiley-Liss, Inc.  相似文献   
50.
We have evaluated, both clinically and by linkage analysis, a large family with 22 known affected males with the MASA syndrome (McKusick 303300). Clinical findings varied widely amongst the affected family members, with some appearing initially to have the MASA syndrome and others to have X-linked hydrocephalus (HSAS) (McKusick 307000). Important findings included the presence of adducted thumbs in two obligate carriers, learning problems or mild mental retardation in three females, two of whom were obligate carriers, and hydrocephalus with neonatal death in three females born to obligate carriers. X-inactivation analysis in lymphocytes from the two women with adducted thumbs revealed preferential inactivation of one X chromosome, suggesting that nonrandom X-inactivation may be responsible for clinical expression in females. The presence of HSAS in some individuals of this family and the MASA syndrome in others further supports the hypothesis that these two conditions are the result of a mutation in the same gene.  相似文献   
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