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51.
The relationship between gastrointestinal (GI) symptoms and uterine cramping pain at menses, controlling for affective states and prostaglandin synthesis inhibitor use, was examined. A total of 53 women completed a daily diary of symptoms, stool characteristics, and medication use for three consecutive menstrual cycles. There were significant across-women and within-woman relationships between stomach pain, nausea, and uterine cramping pain, but not between cramping pain and constipation, diarrhea, or stool characteristics. These results support the presence of a similar mechanism in the generation of distressing GI symptoms and uterine cramping pain at menses. © 1996 John Wiley & Sons, Inc.  相似文献   
52.
Undifferentiated nasopharyngeal carcinoma is associated with Epstein-Barr virus (EBV) infection. Presence of EBV IgA antibodies is rare among healthy individuals and is used as a marker of nasopharyngeal carcinoma in high-incidence populations. Reasons for EBV IgA seropositivity are unknown, but high EBV IgA levels have been found among unaffected close family members and spouses to nasopharyngeal carcinoma patients in Chinese populations. In Greenland, a nasopharyngeal carcinoma-high-incidence area, we compared EBV serology and viral load in high-risk nasopharyngeal carcinoma family members (N = 20) and controls without nasopharyngeal carcinoma-affected relatives (N = 90). There was no significant difference in EBV viral loads between relatives and controls, and EBV was detected in plasma in 5.0% of relatives and 11.4% of controls. There was no significant difference in EBV serology, but the seroprevalence of EBV viral capsid antigen (VCA) IgA was high in both relatives (25.0%) and controls (20.5%). Compared with anti-VCA IgA-negative, anti-VCA IgA-positive individuals had significantly higher EBV viral loads in peripheral blood mononuclear cells (PBMCs) (P < 0.01). The very high prevalence of anti-VCA IgA indicates that this antibody is unsuitable for nasopharyngeal carcinoma screening among Inuits.  相似文献   
53.
Wright  DG; Kenney  RF; Oette  DH; LaRussa  VF; Boxer  LA; Malech  HL 《Blood》1994,84(4):1257-1267
Recombinant human granulocyte colony-stimulating factor (G-CSF) treatment has been shown to increase average neutrophil counts substantially in patients with childhood-onset cyclic neutropenia (or "cyclic hematopoiesis"), but not to eliminate the cyclic oscillations of neutrophil counts or those of other blood elements (monocytes, platelets, eosinophils, and reticulocytes) that are characteristic of this hematopoietic disorder. Indeed, oscillations of neutrophil counts are amplified during G-CSF treatment. We have compared the effects of recombinant granulocyte-macrophage-CSF (GM-CSF) with those of G-CSF in three patients with this disease (2 men and 1 woman, 17, 30, and 32 years of age). These patients were treated with GM-CSF (2.1 micrograms/kg/day, subcutaneously) for 6 weeks, preceded and followed by 6 to 13 weeks of detailed observation to document changes in the cyclic oscillations of blood neutrophils and other blood elements; two of the patients were subsequently treated with G-CSF (5.0 micrograms/kg/d, subcutaneously) and observed for comparable periods of time. Unlike G-CSF treatment, which increased average neutrophil counts more than 20-fold, GM-CSF increased neutrophil counts only modestly, from 1.6- to 3.9-fold, although eosinophilia of varying prominence was induced in each patient. However, at the same time, GM-CSF treatment dampened or eliminated the multilineage oscillations of circulating blood elements (neutrophils, monocytes, platelets, and/or reticulocytes) in each of the patients. In contrast, G-CSF treatment of the same patients markedly amplified the oscillations of neutrophil counts and caused the cycling of other blood elements (monocytes in particular) to become more distinct. These findings support the conclusion that the distinctive cycling of blood cell production in childhood-onset cyclic neutropenia results from abnormalities in the coordinate regulation of both GM-CSF-responsive, multipotential progenitor cells and G-CSF-responsive, lineage-restricted, neutrophil progenitors.  相似文献   
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CRF stimulates the synthesis and secretion of proopiomelanocortin-derived peptides from AtT-20 mouse pituitary tumor cells. This study has shown that there is a specific binding site for CRF located on the plasma membrane of these cells. Both [125I]iodo-Tyr0CRF and noniodinated CRF (10(-11)-10(-7) M) stimulated, in a dose-dependent manner, the secretion of equimolar amounts of beta-endorphin-like immunoactivity from AtT-20 cells. Disuccinimidyl suberate, a cross-linking agent, was used to demonstrate specific binding of [125I]iodo-Tyr0CRF to plasma membranes from these cells. After cross-linking [125I] iodo-Tyr0CRF, the membrane proteins were solubilized with sodium dodecyl sulfate and electrophoresed on a 10% polyacrylamide gel. A single radioactively labeled band, corresponding to a mol wt of 66,000, was identified by autoradiography. [125I]Iodo-Tyr0CRF binding to these membranes was inhibited by 10(-7) M unlabeled CRF or an equimolar concentration of the CRF analog sauvagine. Similar concentrations (10(-7) M) of TRH, GnRH, insulin, [Arg8]vasopressin, somatostatin, and ACTH did not inhibit [125I]iodo-Tyr0CRF binding to the plasma membranes. Incubation of AtT-20 cells for 24 h in the presence of 10 nM dexamethasone reduced [125I]iodo-Tyr0CRF binding by 80% compared to that in untreated cells. Dexamethasone also inhibited the CRF-stimulated beta-endorphin-like immunoactivity secretory response. These data indicate that binding of CRF to a specific membrane protein is an integral component in the stimulation of AtT-20 cells by CRF.  相似文献   
57.
Clark  LJ; Chan  LS; Powars  DR; Baker  RF 《Blood》1981,57(4):675-678
Negative charges on the external surface of red cells were visualized by colloidal iron hydroxide labelling of 50% of the membrane area after osmotic hemolysis and glutaraldehyde fixation. Counts were made over randomly selected areas on electron micrographs at 350,000 x magnification. Statistical analyses showed that at the 95% level of confidence there was no significant difference between oxygenated normal (AA) and sickle (SS) cells in either the distribution or the density of negative charges.  相似文献   
58.
In 9 of the 14 national samples of diabetic patients assembled for the WHO Multinational Study of Vascular Disease in Diabetes additional laboratory data made it possible to relate manifestations of macrovascular disease to blood glucose concentrations as well as to diabetes duration and to other potential determinants. In five of the samples, serum triglyceride concentrations were also measured and were included in simple and multivariate analyses. Ischemic heart disease defined from Minnesota-coded EKGs and standardized WHO questionnaires was more strongly associated with serum triglyceride concentrations than with serum cholesterol concentrations, an association less notable in non-insulin-dependent diabetic patients. Ischemic heart disease was not related to the single fasting plasma glucose estimated for this study. Stroke and amputation were much more strongly related to the known duration of diabetes than was ischemic heart disease, and they were both related to blood glucose concentration measured at the time of study. Despite major variation in arterial disease prevalence rates between collaborating centers, risk for diabetic women appeared to equal that for diabetic men. The major variation in arterial disease prevalence between national groups could be accounted for only in part by the risk factors studied. Other factors, genetic or more likely environmental, are likely to contribute to the variation in arterial disease susceptibility and, if definable, may be potentially preventable.  相似文献   
59.
运动性心律失常是指发生于机体剧烈运动期间或之后的心律失常。临床表现不一,从心悸、头晕、晕厥、心绞痛、急性心肌梗死和充血性心力衰竭,甚至到心脏性猝死。运动性心律失常可见于心肌缺血,如患有动脉粥样硬化性心脏病以及患有原发性或继发性心肌病的患者。然而,也可能发生在似乎健康的个体。在后一组人群中,运动性心律失常可以是良性的,但也可以是获得性(如药物诱发)或先天性(如先天性长QT综合征或致心律失常性右室发育不良)心电活动或结构的异常而呈恶性。这种潜在病理生理学机制的复杂性,使运动性心律失常的诊断和治疗成为临床医学上的…  相似文献   
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