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71.
Monoclonal antibodies were raised against pregnancy-associated endometrial alpha 1-globulin (alpha 1-PEG), a 32 KD insulin-like growth factor binding protein (IGF-BP), which represents a major secretory product of the human decidualized endometrium during pregnancy. This class of IGF-BP has been implicated in the modulation of action, inhibitory and stimulatory, of insulin-like growth factors. Immunization with the protein purified from pregnancy endometrium resulted after myeloma fusion in the isolation of six hybridoma clones and the antibodies produced were characterized. The Ka of the antibodies ranged between 4.75 x 10(9) M-1 and 0.7 x 10(8) M-1. In Western blots all monoclonal antibodies reacted with purified protein of molecular weight 32 KD and specifically detected this IGF-BP species in culture medium and cytosolic extracts of pregnancy endometrium and amniotic fluid. The monoclonal antibodies appear to define three epitope-bearing regions as evidenced by their reactivity to polypeptide fragments of the protein. After synthesis and secretion by tissue explants in vitro the protein is susceptible to cleavage into fragments possessing different monoclonal antibody-defined reactivity. Employing immunohistochemical techniques the protein was principally localized to decidual cells in tissue sections of pregnancy endometrium and solely to these cells after enzymic digestion of the tissue. The implications of these results are discussed with respect to potential role of IGF-BP in the action of IGF upon the IGF-1 receptor-bearing populations, including lymphocytes and trophoblast cells, D in the decidua.  相似文献   
72.
In 4 patients with neuronal ceroid-lipofuscinoses (NCL) (3 patients with the junvenile type, 1 patient with the late infantile type), the ultrastructural spectrum of residual bodies in the central and peripheral nervous system presented curvilinear profiles in all cases and regions investigated and many more ultrastructural patterns within and beyond regions commonly accessible to biopsy, probably due to age dependence, local tissue and cellular biochemical factors. Sampling from basal ganglia especially yielded combined curvilinear-fingerpint bodies, from peripheral ganglia additional membranous bodies. Residual bodies in NCL were present in almost every cell type, similar to the distribution of regular lipofuscin. Although the classical subgroups of NCL contain electronmicroscopically well defined residual bodies, permitting distinction of the late infantile type from the juvenile type, the ultrastructural differences are more of a quantitative than of a qualitative nature. However, they are not pathognomonic. N.m.r. spectra of ceroid and lipofuscin support the concept of their biochemical similarity, and argue against the proposition that they contain a single major component.  相似文献   
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A Rami  A Rabié  A J Patel 《Neuroscience》1986,19(4):1207-1216
A quantitative autoradiographic histological study was carried out to examine mechanisms underlying the reduction in the rates of growth and of cell acquisition, including that of granule cells, in the dentate gyrus of hypothyroid rats. Thyroid deficiency in early life had no effect on the replication of intrinsic cells present in the polymorph and granular layers. The pyknotic index was also normal in the "proliferative zone", polymorph layer and granule cell layer, indicating that thyroid hormone had no effect on the survival of replicating, migrating or maturing granule cells. By contrast, the arrival of migrating cells from the "proliferative zone" to the granular layer was severely retarded in thyroid deficiency. This deficit was rapidly restored after a physiological dose of thyroxine given to hypothyroid rats. The present findings are consistent with our previous proposal that the role of thyroid hormone in the formation and/or the maintenance of nerve cells is related to changes in either cell migration or maturation, rather than to alterations in the replication of germinal cells.  相似文献   
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Sitosterolaemia (also known as phytosterolaemia, MIM 210250) is a rare recessive autosomal inherited disorder, characterised by the presence of tendon and tuberous xanthomas, accelerated atherosclerosis and premature coronary artery disease. The defective gene is hypothesised to play an important role in regulating dietary sterol absorption and biliary secretion, thus defining a molecular mechanism whereby this physiological process is carried out. The disease locus was localised previously to chromosome 2p21, in a 15 cM interval between microsatellite markers D2S1788 and D2S1352 (based upon 10 families, maximum lodscore 4.49). In this study, we have extended these studies to include 30 families assembled from around the world. A maximum multipoint lodscore of 11.49 was obtained for marker D2S2998. Homozygosity and haplotype sharing was identified in probands from non-consanguineous marriages from a number of families, strongly supporting the existence of a founder effect among various populations. Additionally, based upon both genealogies, as well as genotyping, two Amish/Mennonite families, that were previously thought not to be related, appear to indicate a founder effect in this population as well. Using both homozygosity mapping, as well as informative recombination events, the sitosterolaemia gene is located at a region defined by markers D2S2294 and Afm210xe9, a distance of less than 2 cM.  相似文献   
77.
BACKGROUND: The aim of this study was to quantify blood vessel density (BVD) and immunoreactive vascular endothelial growth factor (VEGF) levels in endometrial biopsies taken from women suffering breakthrough bleeding (BTB) under different exogenous hormonal regimes. METHODS: Endometrial biopsies from women in Melbourne with BTB were divided into four groups: combined-continuous hormone therapy (HT) (estrogen and progestin taken daily), cyclical HT (daily estrogen with progestin for 14 days each cycle), progestin-only, or no HT. Subjects from Barcelona were using the Mirena intrauterine levonorgestrel-releasing system for contraceptive purposes, with menstrual diaries for classification into four groups (amenorrhea, infrequent, regular and prolonged). Control biopsies from Melbourne were included in the study. Endometrial samples were immunostained for VEGF and blood vessel localization using an antibody to CD34. RESULTS: Results showed that BVD was significantly reduced in the progestin-only treated group compared with the other three treatment groups (P = 0.028). In addition, all four Mirena BTB groups had significantly reduced BVD compared with controls. Considerable heterogeneity was observed in VEGF immunostaining within and between individual samples with no major differences between HT or Mirena. CONCLUSION: These results provide strong evidence that unopposed progestins reduce endometrial BVD and that there is no link between VEGF immunostaining and BVD or BTB.  相似文献   
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BACKGROUND: There are few longitudinal studies of patients with medically unexplained symptoms. The aim of this study was to investigate outcome in frequent attenders in secondary care who present repeatedly with medically unexplained symptoms. METHOD: Forty-eight patients presenting with medically unexplained symptoms, from a sample of 61, participated in a 3-year follow-up study. Psychiatric morbidity, functional impairment and use of services were evaluated. RESULTS: At follow-up there was a high prevalence of psychiatric morbidity with 69% having at least one psychiatric diagnosis. The sample continued to be high users of a range of health services and substantial functional impairment was reported. CONCLUSION: In this group of frequent attenders with medically unexplained symptoms outcome as measured by psychiatric morbidity, service use and functional impairment remained poor after 3 years.  相似文献   
80.
Alveolar overdistension during mechanical ventilation causes leukocyte sequestration, leading to lung injury. However, underlying endothelial cell (EC) mechanisms are undefined. In a new approach, we exposed isolated blood-perfused rat lungs to high tidal volume ventilation (HV) for 2 h, then obtained fresh lung endothelial cells (FLEC) by immunosorting at 4 degrees C. Immunoblotting experiments indicated that as compared with FLEC derived from lungs ventilated at low volume (LV), HV markedly enhanced tyrosine phosphorylation (TyrP). The tyrosine kinase blocker, genistein, inhibited this response. HV also induced focal adhesion (FA) formation in FLEC, as detected by immunofluorescent aggregates of the alpha(v)beta(3) integrin that co-localized with aggregations of focal adhesion kinase (FAK). Immunoprecipitation and blotting experiments revealed that HV increased TyrP of the FA protein, paxillin. In addition, HV induced a paxillin-associated P-selectin expression on FLEC that was also inhibited by genistein. However, HV did not increase lung water. These results indicate that in HV, EC signaling in situ causes FA formation and induces TyrP-dependent P-selectin expression. These signaling mechanisms may promote leukocyte-mediated responses in HV.  相似文献   
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