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41.
Testing the Initial Efficacy of a Mailed Screening and Brief Feedback Intervention to Reduce At‐Risk Drinking in Middle‐Aged and Older Adults: The Comorbidity Alcohol Risk Evaluation Study 下载免费PDF全文
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Corticosteroids have the ability to suppress the production of growth factors and cytokines and are thus implicated in the negative regulation of hematopoiesis. We have shown that the corticosteroids, prednisolone and dexamethasone, were able to effectively protect progenitor cells in four strains of mice against cell-cycle-specific antimetabolic chemotherapy agents. The highest levels of protection against 5-fluorouracil (FU; 200 mg/kg) were achieved when two or three intraperitoneal injections of dexamethasone were administered between - 7 and +3 hours at a dose of 7.5 mg/kg/injection (optimal dose) or by continuous infusion between -4 and +20 hours. This protective effect is manifested as an increase in the number of high proliferative potential colony-forming cells that survive in the bone marrow 3 days after treatment with FU from between 0.5% and 11% to between 10% and 34% of normal. The bone marrow progenitors and blood cell numbers return to normal from 3 to 5 days and 1 to 2 days earlier, respectively. Less dexamethasone than prednisolone is required to give an equivalent protective effect, which is consistent with their anti-inflammatory potency. These findings are further evidence of the negative regulatory role played by corticosteroids, and indicate that the treatment schedules of corticosteroids during cancer therapy need to be reexamined to obtain the maximum benefit from their use. 相似文献
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Dr. Elaine B. Feldman MD Regina Watt AB Daniel S. Feldman MD 《Digestive diseases and sciences》1977,22(5):415-418
Effects of bile salts on intestinal glucose transfer differ in diverse animal preparations exposed to various bile acids. Radiolabeled glucose influx into rat jejunum in vitro was studied in buffer and compared to taurodeoxycholate, taurochenodeoxycholate, taurocholate, and deoxycholate. Jejunum was obtained from intact, bile-diverted, and colestipoltreated rats and in similar categories after abdominal x-irradiation. Taurodeoxycholate but not taurocholate inhibited glucose influx only in bile-fistula and colestipol-treated rats. Bile diversion increased and colestipol decreased glucose uptake from buffer. Added inhibitory effects of irradiation and bile salts were seen in bile-fistula animals. These data suggest that normal exposure to bile is chronically inhibiting jejunal glucose transport and that dihydroxy bile salts are responsible for this effect. They do not provide an explanation for the role of bile in the intestinal radiation syndrome.This work was supported in part by contract No. AT-(40-1) 3882 from the U.S. Atomic Energy Commission.These data were presented in part at the annual meeting of the Southern Society for Clinical Investigation, New Orleans, La. February, 1975. 相似文献
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Femke?DH?Koedijk Birgit?HB?van BenthemEmail author Eliane?MDC?Vrolings Wim?Zuilhof Marianne?AB?van der Sande 《Emerging themes in epidemiology》2014,11(1):12
Background
Men having sex with men (MSM) remain the largest high-risk group involved in on-going transmission of sexually transmitted infections (STI), including HIV, in the Netherlands. As risk behaviour may change with age, it is important to explore potential heterogeneity in risks by age. To improve our understanding of this epidemic, we analysed the prevalence of and risk factors for selected STI in MSM attending STI clinics in the Netherlands by age group.Methods
Analysis of data from the national STI surveillance system for the period 2006–2012. Selected STI were chlamydia, gonorrhoea, infectious syphilis and/or a new HIV infection. Logistic regression was used to identify factors associated with these selected STI and with overall STI positivity. Analyses were done separately for MSM aged younger than 25 years and MSM aged 25 years and older.Results
In young MSM a significant increase in positivity rate was seen over time (p?<?0.01), mainly driven by increasing gonorrhoea diagnoses, while in MSM aged 25 and older a significant decrease was observed (p?<?0.01). In multivariate analyses for young MSM, those who were involved in commercial sex were at higher risk (OR: 1.5, 95% CI: 1.2-1.9). For MSM aged 25 years and older this was not the case. Having a previous negative HIV test was protective among older MSM compared to those not tested for HIV before (OR: 0.8, 95% CI: 0.8-0.8), but not among younger MSM.Conclusions
MSM visiting STI clinics remain a high-risk group for STI infections and transmission, but are not a homogenous group. While in MSM aged older than 25 years, STI positivity rate is decreasing, positivity rate in young MSM increased over time. Therefore specific attention needs to be paid towards targeted counselling and reaching particular MSM sub-groups, taken into account different behavioural profiles.50.
Erythrocyte Na+,K+ cotransport and Na+,K+ pump in black and caucasian hypertensive patients 总被引:1,自引:0,他引:1
Alterations in red blood cell (RBC) Na+,K+ pump and in Na+,K+ cotransport (CoT) have been described in essential hypertension (EH). We examined pump and CoT in 50 normotensive (NT) subjects and 58 EH subjects subdivided by race and family history of hypertension (+ FH). RBCs were preloaded with Na+ to obtain intracellular levels of 25 mM/liter cells by using the p-chloromercuribenzene sulfonic acid (pCMBS) method. Na+ and K+ efflux rates into a magnesium-sucrose medium were quantitated in the presence of ouabain and ouabain plus furosemide to define pump and CoT activity respectively. Mean intracellular Na+ content was higher (p less than 0.05) in black NT and HT subjects compared to Caucasians. Mean RBC CoT was lower in black EH compared to NT and compared to Caucasian NT and HT subjects. Conversely, Caucasian HT patients had higher mean CoT than NT subjects. Subdivision into + FH revealed very little effect of + FH on CoT in black NT and HT subjects. In Caucasian NT and HT subjects with + FH, mean CoT was significantly reduced (less than 0.3 mM/liter cells/hr) compared to those without + FH. A subgroup of Caucasian EH subjects displayed high CoT (greater than 0.6 mM/liter cells/hr); a + FH had little impact on the high CoT group. There was no correlation between RBC CoT activity and age, sex, severity of hypertension, urinary sodium excretion, and plasma aldosterone. There was a positive correlation (r = + 0.47; p less than 0.01) between CoT and upright plasma renin activity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献