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991.
Specificity of antibodies to immunodominant mycobacterial antigens in pulmonary tuberculosis. 总被引:28,自引:6,他引:28 下载免费PDF全文
P S Jackett G H Bothamley H V Batra A Mistry D B Young J Ivanyi 《Journal of clinical microbiology》1988,26(11):2313-2318
A serological survey was performed in groups of patients with active sputum smear-positive or smear-negative pulmonary tuberculosis, healthy household contacts, and controls. Sera were tested for titers of antibodies which bound to each of five purified mycobacterial antigens by enzyme immunoassay and for competition of binding to single epitopes, using six radiolabeled monoclonal antibodies directed toward corresponding molecules. The evaluation of diagnostic specificity was based on a positive score represented by titers above the cutoff point of 2 standard deviations above the mean titer of a control group. For smear-positive samples, the best sensitivity (83%) was achieved by exclusive use of the 38-kilodalton (kDa) antigen or its corresponding monoclonal antibodies. For smear-negative samples, levels of antibodies binding to the 19-kDa antigen showed a lower sensitivity of 62% compared with the control group or 38% compared with the contact group. Titers of antibody binding to the 14-kDa antigen were raised in Mycobacterium bovis BCG-vaccinated contacts, indicating that the greatest potential of this antigen may be in the detection of infection in a population for which tuberculin testing is unreliable. The results demonstrated the differing antibody responses to each of the tested antigens and distinct associations with the stage of infection or disease. 相似文献
992.
A distinctive glomerular lesion complicating placental site trophoblastic tumor: report of two cases 总被引:1,自引:0,他引:1
Renal disease with distinctive pathologic features developed in two young women who had placental site trophoblastic tumors. The renal abnormalities were manifested by proteinuria in both cases and by hematuria in one case; blood pressure was elevated in one of the patients. Pathologic examination of the kidneys showed distinctive glomerular abnormalities, characterized mainly by the presence of occlusive eosinophilic deposits in many of the glomerular capillary lumina, most of which stained for fibrinogen-related antigens and IgM by immunohistochemical techniques. Ultrastructural examination showed the deposits to consist mainly of granular material that contained packets of fibrillar material with the appearance of fibrin. The uterine tumors were composed of mononucleated and multinucleated cells with abundant cytoplasm that infiltrated between the muscle bundles of the myometrium; in both tumors there was prominent deposition of eosinophilic material that had the tinctorial properties of fibrin and that stained for fibrinogen and IgM in immunoperoxidase studies. The renal abnormalities disappeared after hysterectomy in one case; the other patient, who was receiving chemotherapy and had disseminated intravascular coagulation, died with leukopenia and sepsis. The clinical and pathologic features in these cases suggest that the renal abnormalities were related to the uterine tumors and that the production of immune complexes and/or the activation of intravascular coagulation by the tumors were pathogenetic mechanisms. 相似文献
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995.
We contrast naming from pictures, and reading words, for objects and verbs (actions relating to the objects) in a patient with a large, posterior left-hemisphere lesion. We present evidence for spared picture naming for verbs relative to objects, whilst the opposite pattern of sparing occurred in reading. Objects were also spared relative to verbs in tasks requiring that written words be matched to either pictures or auditory words, in the presence of semantically related or unrelated distractors. We conclude that verb semantics were more impaired than semantic knowledge for objects, and that the better semantic knowledge for object names supported word reading. With pictures, however, action verb retrieval was maintained through a nonsemantic route from vision to action, or though preserved right-hemisphere "action semantics." 相似文献
996.
Tangir J Bonafé N Gilmore-Hebert M Henegariu O Chambers SK 《Clinical & experimental metastasis》2004,21(6):477-483
The aggressive behavior of breast cancer cells can at times be modulated by hormonal mechanisms. Exposure to glucocorticoids
(GC) has been shown to stimulate the invasiveness, motility and adhesiveness of breast cancer cells containing the glucocorticoid
receptor. This is largely explained by GC-associated overexpression of the c-fms proto-oncogene, which encodes the receptor for the colony stimulating factor-1 (CSF-1). Our objective is to investigate additional
GC-associated genetic alterations that could modulate c-fms related malignant behavior in breast cancer cells. A microarray technique using an oligonucleotide array representing 16,700
known expressed human genes was used to analyze the gene expression profile of breast cancer cells exposed to dexamethasone
(Dex) or vehicle. Results were confirmed by western blot analysis. Six genes were found to be consistently differentially
overexpressed in the Dex-exposed cells compared to control. We focused on serum-glucose kinase 1 (SGK1), a serine-threonine
kinase known to be involved in intracellular signal transduction pathways and induced by GC and serum. An adhesion assay was
performed on extracellular matrix after exposing the breast cancer cells to Dex, CSF-1 or to Dex or CSF-1 plus LY294002, a
functional inhibitor of SGK1 action. Exposure to LY294002 significantly decreased both CSF-1 and Dex-induced adhesiveness
to the level of control cells. SGK1 may act as a downstream intracellular regulator of c-fms, particularly of c-fms-induced adhesiveness of breast cancer cells after exposure to GC or CSF-1. This finding may have implications for potential
therapeutic interventions aimed at decreasing the aggressiveness of breast cancer cells.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
997.
This study was performed to investigate the effects of behavior modification on body image, depression and body fat in obese elementary school children. Sixty-two elementary students of the 4th to 6th grade were selected from two different Seoul schools. Thirty-four children in one school were designated as the experimental group, and 28 children from the other school as the control group. The experimental group received 60 - 70 minutes of behavior modification, once a week, for 8 weeks. The control group received neither management nor treatment. The results indicated a significant improvement of body image and a reduction in the increase rate of body fat for the experimental group. This finding strongly supports the theory that behavior modification can be used as an effective strategy in the treatment of obese children. 相似文献
998.
Alexander S. Graphodatsky Polina L. Perelman Natalya V. Sokolovskaya Violetta R. Beklemisheva Natalya A. Serdukova Gauthier Dobigny Stephen J. O’Brien Malcolm A. Ferguson-Smith Fengtang Yang 《Chromosome research》2008,16(1):129-143
Canid species (dogs and foxes) have highly rearranged karyotypes and thus represent a challenge for conventional comparative
cytogenetic studies. Among them, the domestic dog is one of the best-mapped species in mammals, constituting an ideal reference
genome for comparative genomic study. Here we report the results of genome-wide comparative mapping of dog chromosome-specific
probes onto chromosomes of the dhole, fennec fox, and gray fox, as well as the mapping of red fox chromosome-specific probes
onto chromosomes of the corsac fox. We also present an integrated comparative chromosome map between the species studied here
and all canids studied previously. The integrated map demonstrates an extensive conservation of whole chromosome arms across
different canid species. In addition, we have generated a comprehensive genome phylogeny for the Canidae on the basis of the
chromosome rearrangements revealed by comparative painting. This genome phylogeny has provided new insights into the karyotypic
relationships among the canids. Our results, together with published data, allow the formulation of a likely Canidae ancestral
karyotype (CAK, 2n = 82), and reveal that at least 6–24 chromosomal fission/fusion events are needed to convert the CAK karyotype
to that of the modern canids.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
999.
Linda Wittkop Daniel Commenges Isabelle Pellegrin Dominique Breilh Didier Neau Denis Lacoste Jean-Luc Pellegrin Geneviève Chêne François Dabis Rodolphe Thiébaut 《BMC medical research methodology》2008,8(1):68
Background
Principal component analysis (PCA) and partial least square (PLS) regression may be useful to summarize the HIV genotypic information. Without pre-selection each mutation presented in at least one patient is considered with a different weight. We compared these two strategies with the construction of a usual genotypic score. 相似文献1000.
S G Lim A Condez C A Lee M A Johnson C Elia L W Poulter 《Clinical and experimental immunology》1993,92(3):448-454
T cell subsets in the gut mucosa are distinct populations and their imbalance in HIV has specific implications in infection. Alterations in T cell subsets in duodenal biopsies were investigated in 17 asymptomatic HIV patients, 24 AIDS patients and 10 controls with non-ulcer dyspepsia. Immunohistochemistry and immunofluorescence using MoAbs to CD3, CD4, CD8, CD68, CD45RA, CD45RO and gp120 were performed on frozen sections. In the lamina propria, there was a significant depletion of CD4+ cells at all stages of HIV, but the density of CD8 lamina propria cells was increased. Intraepithelial lymphocytes were decreased in AIDS patients. There was a significant correlation between cellular density and mucosal CD3+ lymphocytes, and between mucosal CD3+ and CD8+ lymphocytes. Although mucosal CD4,CD45RO+ 'memory' cells were decreased, CD8,CD45RO+ 'memory' cells were increased. Mucosal CD4+ lymphocyte depletion occurred early in HIV, and thus their role in mucosal protection against opportunistic infection should be revised. Mucosal CD8+ lymphocytes initially increased, but decreased when CD4 blood counts were depleted, perhaps contributing to loss of host protection against infection. Intraepithelial lymphocyte depletion may also contribute to opportunistic infection. 相似文献