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91.
Summary Radiation-reduced hybrids for mapping of DNA markers in the pericentromeric region of chromosome 10 were developed. A Chinese hamster/human somatic cell hybrid (762-8A) carrying chromosomes 10 and Y as the only human material were exposed to 40,000 rads of irradiation and then rescued by fusion with non-irradiated recipient Chinese hamster cells (GM459). Southern hybridization analyses revealed that 10 of 128 HAT-resistant clones contained human chromosomal fragments corresponding to at least one marker locus betweenFNRB (10p-11.2) andRBP3 (10q11.2). These hybrids were then used to map microdissection clones previously isolated and roughly mapped to this chromosomal region by fluorescencein situ hybridization (FISH). Two of the six microclones studied could be mapped to the proximity of the D10-S102 locus. These radiation hybrids are useful for the construction of refined genetic maps of the pericentromeric region of chromosome 10.  相似文献   
92.
Forty-four thyroid carcinomas with an Insular component (JC) were reviewed from 2457 tumors diagnosed as papillary (PC) or follicular carcinoma (FC). These tumors were classified as FC with an IC (FCIC; 30 cases) and PC with an IC (PCIC; 14 cases). Both tumors were composed of solid cell nests in some areas and had a tendency toward a characteristic nuclear size: FCIC had a small nucleus and PCIC contained a nucleus of an Intermediate type or a large nucleus similar to that of PC, although there were numerous tumors with an exceptional nuclear size. The mean age and tumor diameter were the highest and largest in FCIC, respectively, followed by PCIC. Among the 44 cases, 17 patients died of the disease, two were alive with the disease and 18 were alive without the disease. From 13 clinicopathological factors, the presence of an IC, age, non-encapsulation, tumor size, vascular invasion and necrosis were found to be independent variables for actual prognosis of FC and PC based on univariate analysis followed by multtvariate analysis. The results of the present study indicate that the presence of an IC is an independent aggressive prognostic factor for patients with PC and FC.  相似文献   
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Sero- and molecular-epidemiological studies on Borna disease virus (BDV) infection show that BDV RNA is not always detected in the peripheral blood mononuclear cells (PBMCs) from serum anti-BDV antibody-positive individuals such as horses, sheep, cattle, cats, and humans. In this study we demonstrated BDV RNA signals by polymerase chain reaction only in restricted regions of the brain from horses with locomotor disease. Four of six horses examined showed apparently positive reactions for anti-BDV antibodies. Specific regions of the brain of these four horses were positive for BDV RNA but the internal organs, lymph nodes, and PBMCs were negative. Histological studies of their brains revealed no apparent histological abnormalities such as inflammatory reactions. These results suggest that BDV chronically infects certain restricted regions of brain in seropositive horses. Received: 6 January 1997  相似文献   
96.
Monoclonal antibodies (McAbs) were raised against the synthesized short peptides corresponding to 37-47 residues in amino acid sequence of human AA protein. The McAbs reacted immunohistochemically to amyloid tissues from cow, mouse, swan, and human AA amyloidosis. We concluded that the McAbs were useful for identification of AA type amyloidosis of various species, and that the 37-47 residues were effective antigenic sites in AA protein.  相似文献   
97.
The specificity of monoclonal antibodies against gastric mucins (designated as HIK1083, PGM 36, and PGM 37) was studied immunohistochemically in normal, metaplastic, and neoplastic human tissues. These antibodies labeled class III mucin-producing cells identified by paradoxical concanavalin A staining in normal stomach, duodenum (Brunner gland), biliary tract, and main pancreatic duct; in mucinous metaplasia of pancreas and gallbladder; and in adenocarcinomas of stomach (90%), bile duct (80%), gallbladder (100%), pancreas (80%), lung (100% of goblet cell type adenocarcinomas), ovary (67% of mucinous carcinomas), and uterine cervix (100% of adenoma malignum tumors). Normal and neoplastic cells of esophagus, colon, salivary gland, kidney, endometrium, breast, prostate, and liver, as well as normal small intestine, lung, and uterine cervix, were all negative. The antibodies used should be valuable for the detection of class III mucin and class III mucin-producing cells in normal, metaplastic, and neoplastic tissues.  相似文献   
98.
We have evaluated the effect of natural human interferon (IFN)-alpha on the growth of chlamydia trachomatis in human epithelial cells in vitro and revealed that IFN-alpha has reduced both growth and infectivity of C. trachomatis. The effect of IFN-alpha was reversed by the addition of exogenous L-tryptophan and iron to the culture medium, suggesting that antichlamydial effect of IFN-alpha was caused by depletion of intracellular tryptophan and iron, both of which are essential for chlamydial growth. When IFN-alpha was combined with another antichlamydial cytokines, IFN-gamma and tumor necrosis factor (TNF)-alpha, the effect was synergistically enhanced. Therefore, IFN-alpha would act coordinately with other cytokines such as IFN-gamma and TNF-alpha, and play an important role in host defense against infection and in the establishment of persistent chlamydial infection of host, in which the organism remains viable, but in a culture-negative state.  相似文献   
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The present study was performed to evaluate the potential for clinical application of digital linear tomosynthesis in imaging hip prostheses. Volumetric x-ray digital linear tomosysnthesis was used to image hip prostheses. The tomosynthesis was compared to metal artifact reduction (MAR) computed tomography (CT), and non-MAR CT scans of a prosthesis case. The effectiveness of this method in enhancing visibility of a prosthesis case was quantified in terms of the signal-to-noise ratio (SNR), and removal of ghosting artifacts in a prosthesis case was quantified in terms of the artifact spread function (ASF). In the near in-focus plane, the contrast is greater in the MAR CT or tomosynthesis relative to the non-MAR CT. The order of ASF performance of the algorithm was as follows: (1) tomosynthesis; (2) MAR-CT; (3) non-MAR CT. The potential usefulness of digital linear tomosynthesis for evaluation of hip prostheses was demonstrated. Further studies are required to determine the ability of digital linear tomosynthesis to quantify the spatial relationships between the metallic components of these devices as well as to identify bony changes with diagnostic consequences.  相似文献   
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