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71.
Hormonally functional ovarian neoplasms are those tumors that secrete one or more hormones that are clinically manifested
in the patient. The hormone production may have implications for the diagnosis, management, or treatment of the patient. Hormonally
functional ovarian neoplasms include tumors that belong to various histologic categories and produce a variety of hormonal
effects. Functional ovarian tumors most commonly produce steroid hormones, and such tumors frequently belong in the sec cordstromal
and steroid cell categories. In addition, a wide variety of peptide hormones may be produced by ovarian tumors. Although in
most instances the neoplastic cells themselves produce the hormones, a wide variety of tumors may induce their stroma to produce
steroid hormones. The stroma of ovarian tumors is derived from the ovarian stroma and may, on occasion, resemble specialized
ovarian stroma and its derivatives. Cells resembling luteinized stromal cells or luteinized theca cells may be present and
appear to be responsible for the resultant hormone secretion. 相似文献
72.
Identification of novel regions of allelic loss from a genomewide scan of esophageal squamous-cell carcinoma in a high-risk Chinese population 总被引:17,自引:0,他引:17
Hu N Roth MJ Polymeropolous M Tang ZZ Emmert-Buck MR Wang QH Goldstein AM Feng SS Dawsey SM Ding T Zhuang ZP Han XY Ried T Giffen C Taylor PR 《Genes, chromosomes & cancer》2000,27(3):217-228
Esophageal cancer is one of the most common fatal cancers worldwide. Deletions of genomic regions are thought to be important in esophageal carcinogenesis. We conducted a genomewide scan for regions of allelic loss using microdissected DNA from 11 esophageal squamous-cell carcinoma patients with a family history of upper gastrointestinal tract cancer from a high-risk region in north central China. Allelic patterns of 366 fluorescently labeled microsatellite markers distributed at 10-cM intervals over the 22 autosomal chromosomes were examined. We identified 14 regions with very high frequency (>/= 75%) loss of heterozygosity (LOH), including broad regions encompassing whole chromosome arms (on 3p, 5q, 9p, 9q, and 13q), regions of intermediate size (on 2q, 4p, 11p, and 15q), and more discrete regions identified by very high frequency LOH for a single marker (on 4q, 6q, 8p, 14q, and 17p). Among these 14 regions were 7 not previously described in esophageal squamous-cell carcinoma as having very high frequency LOH (on 2q, 4p, 4q, 6q, 8p, 14q, and 15q). The very high frequency LOH regions identified here may point to major susceptibility genes, including potential tumor suppressor genes and inherited gene loci, which will assist in understanding the molecular events involved in esophageal carcinogenesis and may help in the development of markers for genetic susceptibility testing and screening for the early detection of this cancer. Genes Chromosomes Cancer 27:217-228, 2000. Published 2000 Wiley-Liss, Inc. 相似文献
73.
Wehrmeyer JA Barthel JA Roth JP Saifuddin T 《Medical & biological engineering & computing》1998,36(4):475-479
A testing device is developed that determines the stiffness, or flexural rigidity, of an endoscope at specific locations down
its length by subjecting it to a compressive axial force, a situation similar to the actual forces applied to the endoscope
during a clinical procedure. The endoscope is made to deform in a similar fashion to a slender buckled column and the force
causing this deformation is related to the flexural rigidity using column buckling theory. A direct relationship between the
critical load needed to cause buckling and the square of column length L is demonstrated experimentally and is expected theoretically,
giving confidence in the application of column buckling theory to endoscope testing. Additional confidence in the validity
of the columnbuckling test results is obtained by their similarity to data obtained by subjecting the endoscope to a transverse
load, determining deflection, and modelling the endoscope as a bent elastic beam. Several makes and models of endoscopes were
tested, with flexural rigidity values typically ranging between 160 to 240 Ncm2. The effect of a metal stiffener inserted in an endoscope's accessory channel is quantified, as is the change in flexural
rigidity down the insertion shaft of a graded-stiffness endoscope. Significant differences in flexural rigidity were obtained
between identical endoscopes, each sharing similar usage histories, indicating the need for flexural rigidity measurements
for each individual endoscope of a particular model line, though a more extensive study is required to reliably determine
scope-to-scope stiffness variations for a particular model line. 相似文献
74.
Yide Jin Laphalle Fuller Manuel Carreno Keith Zucker David Roth Violet Esquenazi Theodore Karatzas Sidney J. Swanson III Andreas G. Tzakis Joshua Miller 《Journal of clinical immunology》1997,17(2):140-153
Liver infiltrating lymphocytes (LIL) were isolated from HCV-positive (+) and HCV-negative (–) end-stage livers. Phenotypic analysis and functional studies using proliferative and lymphocytotoxic assays were performed with the isolated LIL. Two CD3+ lymphocyte populations were found in LIL using FITC anti-CD3 monoclonal antibodies (mAb). One was a bright fluorescence intensity population (as in PBL), and the other dim. We calculated the number of FITC-anti-CD3 mAbs bound per lymphocyte on PBL and LIL and found 80,040 ± 4628 and 39,615 ± 3932, respectively. Therefore, HCV+ and HCV– patient PBL contained approximately twice the number of CD3 molecules per cell than patient CD3+ LIL. LIL also contained approximately a threefold higher concentration of TCR+, CD4–CD8–, and CD56,16 (NK) cells than the patient PBL. Thus, a major subset of LIL is phenotypically similar to mouse NK1.1+ intermediate T cells. LIL freshly isolated from HCV+ livers exhibited weak CTL activity against EBV- or Con A-transformed lymphoblast targets infected with vaccinia–HCV recombinant virus (rHCV) or primary hepatocyte cultured cells. However, after in vitro coculture of LIL with rHCV, these cells developed a strong cytotoxicity for the above targets. In contrast, LIL from HCV– livers were not cytotoxic against the same targets. Histochemical studies (in situ) demonstrated that these hepatocytes express CD95, and stains demonstrated apoptosis. The HCV+ hepatocytes also express class I MHC molecules and ICAM-1. The addition of mAb specific for these adhesion molecules inhibited CML activity. Short-term cultured hepatocytes (targets) from HCV+ and HCV– patients produced low levels of cytokines IL-1, IL-2, IL-6, TNF, and IFN- but a high level of IL-8. It is speculated that LIL expressing reduced numbers of CD3 molecules may even function as immune regulators as proposed for intermediate T cells in mice. 相似文献
75.
76.
Marie-Paule Roth Laurence Dolbois Nicolas Borot Claire Amadou Michel Clanet Pierre Pontarotti Hlne Coppin 《Human immunology》1995,43(4):276-282
The MOG locus, located on chromosomal bands 6p21.3-p22 and mapped about 100 kb telomeric to HLA-F, was isolated from cosmid ICRFcl09A2434 and shown to contain three microsatellites. These CA-repeat polymorphic markers were characterized in a sample of 173 healthy unrelated individuals and 84 DNAs from the HLA Workshop reference panel, by a method combining fluorescence labeling of PCR products and use of an automated DNA sequencer. For the three markers, frequencies of heterozygotes are well predicted from allele frequencies by the Hardy—Weinberg rule, which suggests that problems of allele nonamplification are unlikely. Typing of cell lines homozygous in the HLA region allowed unambiguous definition of 81 HLA-MOG haplotypes and showed that several HLA ancestral haplotypes extended to the MOG region. The high degree of polymorphism (59%, 51%, and 81% at the three loci, respectively, and 87% at the haplotype level) makes these new markers informative for association or linkage studies with diseases such as hemochromatosis or multiple sclerosis, and for studies aimed at precisely delineating the site of crossover in chromosomes in which recombination occurred in the distal part of the HLA class I region. 相似文献
77.
To investigate the immunogenicity and protective efficacy of cold-adapted influenza vaccine in individuals with underlying immunity to influenza A virus, we administered cold-adapted H1N1 and H3N2 vaccines to adults with prevaccination serum hemagglutination inhibition antibody titers of 1:16 or more and challenged them 1 month afterwards with homologous wild-type influenza A virus. Both cold-adapted vaccines were immunogenic in seropositive adults. In addition, individuals receiving cold-adapted vaccines had lower rates of virus shedding and illness following challenge with wild-type influenza virus than did unvaccinated seropositive volunteers. 相似文献
78.
Biotinylation: a simple method for labelling complement component C8 with preservation of functional activity 总被引:1,自引:0,他引:1
Biotinylation of human C8 with the water-soluble biotin derivative biotinylamidohexanoic acid, N-hydroxysulfosuccinimide ester is an excellent method for labelling this terminal complement component with preservation of its functional activity. The biotinylated product can be detected both in native form and also following its incorporation into the terminal complement complexes. Detection assays include Western blotting, crossed immunoblotting, ELISA, and immunocytochemistry. Biotinylation is an attractive alternative method for labelling C8 and may be used for detecting and quantifying C8 and C5b-9 complexes in their soluble and membrane-bound forms. 相似文献
79.
Ultrastructural and immunohistochemical characterization of autonomic neuropathy in genetically diabetic Chinese hamsters 总被引:3,自引:0,他引:3
R E Schmidt D A Plurad S B Plurad B E Cogswell A R Diani K A Roth 《Laboratory investigation; a journal of technical methods and pathology》1989,61(1):77-92
Selected portions of the prevertebral and paravertebral sympathetic and vagal parasympathetic nervous systems have been examined in the genetically diabetic Chinese hamster, an experimental animal model of diabetic gastrointestinal disease. The prevertebral sympathetic superior mesenteric/celiac ganglia, which provide much of the sympathetic innervation of the alimentary tract, developed large numbers of markedly dilated axons, many of which had the ultrastructural features of neuroaxonal dystrophy. Dystrophic axons, many involving presynaptic axonal elements, were increased in frequency in the prevertebral superior mesenteric/celiac ganglia, but not in the paravertebral superior cervical sympathetic ganglia, of chronically diabetic hamsters in comparison with age-matched controls. Dystrophic axons contained substance P- and gastrin-releasing peptide (gastrin-releasing peptide/bombesin)-like staining but were not labeled by antisera directed against vasoactive intestinal peptide, dynorphin-B, somatostatin, leu- and met-enkephalin and neuropeptide tyrosine. Substance P and gastrin-releasing peptide/bombesin containing subpopulations of presynaptic elements in prevertebral sympathetic ganglia are thought to participate in local reflex control of bowel motility and lesions preferentially involving these elements may contribute to bowel dysfunction. Immunohistologic techniques failed to demonstrate dystrophic axons in the superior cervical ganglia. Although morphometric studies failed to show significant axon loss in the abdominal vagus of chronically diabetic Chinese hamsters, evidence of markedly diminished numbers of axons comprising each Schwann cell unit and regenerative collections of Schwann cell processes devoid of axons are consistent with the participation of parasympathetic elements in the pathogenesis of alimentary dysfunction in this model system. These results suggest that selective subpopulations of neuropeptide containing axons are vulnerable to the diabetic condition and that these abnormalities may lead to physiologic dysfunction. 相似文献
80.
Hormonal regulation of human growth 总被引:6,自引:0,他引:6