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91.
A multicolour tandem labelling fluorescence in situ hybridization(FISH) procedure was used to compare the frequencies of radiation-inducedchromosome breakage and hyperdiploidy of chromosome 1 occurringin non-cultured granulocytes and Go lymphocytes with those observedin cultured metaphase and interphase lymphocytes. Whole blood,obtained from healthy male donors, was exposed in vitro to 0,100, 200, 300 and 400 cGy of ionizing radiation from a 137Cssource. Aliquots containing granulocytes and Go lymphocytesfrom each dose were treated immediately with hypotonic KCl onice and harvested. Cells were hybridized with 相似文献
92.
Effects of insulin on diacylglycerol-protein kinase C signaling in rat diaphragm and soleus muscles and relationship to glucose transport 总被引:2,自引:0,他引:2
Insulin was found to provoke rapid increases in diacylglycerol (DAG) content and [3H]glycerol incorporation into DAG and other lipids during incubations of rat hemidiaphragms and soleus muscles. Insulin also rapidly increased phosphatidic acid and total glycerolipid labeling by [3H]glycerol, suggesting that insulin increases DAG production at least partly through stimulation of the de novo pathway. Increased DAG production may activate protein kinase C (PKC) as reported previously in the rat diaphragm. We also observed apparent insulin-induced translocation of PKC from cytosol to membrane in the rat soleus muscle. The importance of insulin-induced increases in DAG-PKC signaling in the stimulation of glucose transport in rat diaphragm and soleus muscles was suggested by 1) PKC activators phorbol esters and phospholipase C stimulation of [3H]-2-deoxyglucose (DOG) uptake and 2) PKC inhibitors staurosporine and polymixin B inhibition of insulin effects on [3H]-2-DOG uptake. Although phorbol ester was much less effective than insulin in the diaphragm, phospholipase C provoked increases in [3H]-2-DOG uptake that equaled or exceeded those of insulin. In the soleus muscle, phorbol ester, like phospholipase C, was only slightly but not significantly less effective than insulin. Similar variability in effectiveness of phorbol ester has also been noted previously in rat adipocytes (weak) and BC3H1 myocytes (strong), whereas DAG, added exogenously or generated by phospholipase C treatment, stimulates glucose transport to a degree that is quantitatively more comparable to that of insulin in each of the four tissues. Differences in effectiveness of phorbol ester and DAG could not be readily explained by postulating that the latter acts independently of PKC, because DAG provoked the apparent translocation of the enzyme from cytosol to membranes in rat adipocytes, and effects of DAG on [3H]-2-DOG uptake were blocked by inhibitors of PKC in both rat adipocytes and BC3H1 myocytes. Collectively, our findings provide further support for the hypothesis that insulin increases DAG production and PKC activity, and these processes are important in the stimulation of glucose transport in rat skeletal muscle and other tissues. 相似文献
93.
Hidradenitis suppurativa, a chronic inflammatory condition of the apocrine gland follicles, may rarely be complicated by pyoderma gangrenosum (PG). We report such a case, in which the immunosuppressant cyclosporin A (CyA) was given to treat PG and a dramatic improvement occurred in the patient's intractable perineal HS. 相似文献
94.
We have examined the effect of prolactin (PRL) on growth-related gene expression, protein kinase C (PKC) activity and diacylglycerol (DAG) mass in rat liver. Hepatic levels of messenger (m)RNA for c-myc, ornithine decarboxylase (ODC) and beta-actin increased in a dose-dependent manner within 1 h after PRL administration. Prolactin also caused a transient elevation of liver DAG levels and particulate-associated PKC activity. The PRL-provoked increases in DAG mass and particulate PKC activity were coincident and maximal at 20 min and began declining toward control levels by 30 min. These results suggest a temporal relationship between PRL-stimulated DAG accumulation and PKC activation. Furthermore, the subsequent rapid induction of growth-related gene expression provides new information on the role of PRL as a hepatic mitogen. 相似文献
95.
The influence of aging on the ability of ethanol to inhibit N-methyl-D-aspartate-stimulated catecholamine overflow in rat brain was examined. Alcohol effects on N-methyl-D-aspartate stimulated [3H]norepinephrine or [3H]dopamine overflow from the cortex, hippocampus, and striatum of aged (24-28 months) middle aged (12-14 months), and young (3-5 months) rats were examined. N-methyl-D-aspartate (500 microM) stimulated catecholamine overflow in all brain regions, with aged rats showing declines in overflow of 33% in the hippocampus and 41% in the striatum. Alcohol (30-200 mM) produced a concentration-dependent inhibition of overflow at all ages and brain regions tested. The IC50 for alcohol inhibition of NMDA-stimulated catecholamine release was not significantly different in aged brain or across brain regions. These results indicate that alcohol's ability to inhibit NMDA-stimulated catecholamine release is not significantly altered with aging. 相似文献
96.
PURPOSE: The purposes of this study were to evaluate self-esteem over 3 years in the 469 myopic children participating in the Correction of Myopia Evaluation Trial (COMET), and to examine its relationship with lens assignment (progressive addition lenses [PALs] vs. single-vision lenses [SVLs]), myopia progression, and several other ocular and demographic characteristics. METHODS: Data collection included refractive error measurements, child-reported visual symptoms, attitude toward glasses, adherence, and self-esteem as measured by the Self-Perception Profile for Children (SPPC). A two-way analysis of variance (treatment group x time) was performed to examine whether PAL and SVL wearers differed in self-esteem over time. Multiple regression analyses were used to evaluate associations between self-esteem at follow-up and relevant factors identified by univariate analyses. RESULTS: Regardless of lens assignment or myopia progression, COMET children reported moderate to high levels of self-esteem at follow-up in the areas of scholastic and athletic competence, physical appearance, social acceptance, behavioral conduct, and global self-worth. Mean scores ranged from 2.87 (+/- 0.68) on athletic competence to 3.40 (+/- 0.56) on global self-worth. Self-esteem changed significantly (p < 0.05) over 3 years in the domains of scholastic competence, social acceptance, and physical appearance. Self-esteem at follow-up was associated with visual symptoms, attitude toward glasses, age, gender, and ethnicity. CONCLUSIONS: Lens assignment and myopia progression were not associated with self-esteem in the COMET cohort. These children had high levels of self-esteem, suggesting that having myopia does not negatively impact self-esteem. Follow-up reports will monitor self-esteem and related factors in this cohort of myopic children over the course of adolescence and early adulthood. 相似文献
97.
To investigate the incidence of use of the flexible and rigid proctosigmoidoscopes by family physicians, a questionnaire was mailed to 1,585 randomly selected members of the American Academy of Family Physicians. Of the total of 1,057 respondents, 48 percent performed sigmoidoscopy, with 30 percent performing flexible sigmoidoscopy, 31 percent performing rigid sigmoidoscopy, and 48 percent performing at least one of the procedures. Younger physicians were found to be more likely to perform flexible sigmoidoscopy, as were physicians who practice in communities of fewer than 500,000 population. Nationwide, more of the flexible procedures are performed in private offices than in the hospital. Physicians in communities of less than 500,000, however, are more likely to use the flexible sigmoidoscope in a hospital setting than are physicians in larger urban areas [corrected]. Board-certified physicians were more likely to perform one or both procedures than were noncertified physicians. 相似文献
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Lorenzo Melani Richard Mills David Hassman Robert Lipetz Leslie Lipka Alexandre LeBeaut Ramachandran Suresh Pabak Mukhopadhyay Enrico Veltri 《European heart journal》2003,24(8):717-728
AIMS: To evaluate the efficacy and safety of ezetimibe 10 mg administered with pravastatin in patients with primary hypercholesterolemia. METHODS AND RESULTS: After dietary stabilization, 2-12 week screening/washout period, and 4-week, single-blind, placebo lead-in period, 538 patients with baseline LDL-C > or =3.8 to < or =6.5 mmol/l and TG < or =4.0 mmol/l were randomized to one of eight possible treatments administered daily for 12 weeks: ezetimibe 10mg; pravastatin 10, 20, or 40 mg; ezetimibe 10 mg plus pravastatin 10, 20, or 40 mg; or placebo. The primary efficacy endpoint was percent reduction in LDL-C from baseline to study endpoint for ezetimibe 10 mg plus pravastatin (pooled doses) compared to pravastatin alone (pooled doses) and ezetimibe alone. The combined use of ezetimibe and pravastatin resulted in significant incremental reductions in LDL-C and TG compared to pooled pravastatin alone (p<0.01). Coadministration therapy reduced LDL-C by 34-41%, TG by 21-23%, and increased HDL-C by 7.8-8.4%, depending on the dose of pravastatin. The combined regimen was well tolerated, with a safety profile similar to pravastatin alone and placebo. CONCLUSIONS: When coadministered with pravastatin, ezetimibe provided significant incremental reductions in LDL-C and TG and was well tolerated with a safety profile similar to pravastatin alone. 相似文献