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Background: Survival benefit with intra-aortic balloon pump (IABP) insertion for coronary artery bypass grafting (CABG) patients with left ventricular dysfunction is controversial. The aim of this study was to assess the early results of CABG that predict 30-day mortality and prolonged length of hospital stay (LOS) after isolated CABG and the role of IABP application as a main predictor in patients with an ejection fraction (EF) of 30% or less. Materials and Methods: Eight hundred and thirty-three patients who underwent isolated CABG with EF 30% as the control group. Demographic and clinical characteristics and postoperative complications were considered. Data were analyzed using the student's t-test and chi-square test for univariate analysis and the analysis of covariance and logistic regression for multivariate analysis. Results: The thirty-day mortality rate (1.6% vs. 0.7%, P P P = 0.002) and prolonged LOS (P = 0.009). Also, urinary tract infection, prolonged ventilation, and renal failure as postoperative complications were statistically more in the group with the application of IABP. Conclusion: Low ejection fraction can positively affect thirty-day mortality and prolonged LOS and ICU stay in patients who undergo CABG. In these patients, IABP insertion is a strong predictor for early complication and mortality.  相似文献   
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Context: Natural products and their compounds are some of the most interesting sources of new drugs. Reviews have reported various pharmacological properties such as antimicrobial effects of Zataria multiflora Boiss (Lamiaceae).

Objective: The present study investigates the chemical composition of Z. multiflora essential oil and evaluates its cytotoxic effects and anti-leishmanial activities against Leishmania tropica in an in vitro model.

Materials and methods: The components of Z. multiflora oil were identified by gas chromatography/mass spectroscopy (GC/MS) analysis. Anti-leishmanial effects of the essential oil (0–100?μL/mL) and methanol extract of Z. multiflora (0–100 μg/mL) on promastigote forms as well as their cytotoxic activities against J774 cells were evaluated using MTT assay for 72 h. The leishmanicidal activity against amastigote forms of L. tropica was evaluated at the concentrations of 0–50 μg/mL in a macrophage model for 48 h.

Results: The chemical analyses demonstrated that the main components of essential oil were thymol (41.81%), carvacrol (28.85%), and p-cymene (8.36%). Regarding leishmanicidal activity, the IC50 values for the essential oil and methanol extract were 3.2?μL/mL and 9.8 μg/mL against promastigote forms and 8.3?μL/mL and 34.6 μg/mL against amastigote forms, respectively. Essential oil (CC50 89.3?μL/mL) indicated a higher cytotoxic effect than the methanol extract (CC50 591.6 μg/mL) of Z. multiflora.

Conclusion: The present study revealed the chemical composition of Z. multiflora that might be a natural source of new anti-leishmanial agents in terms of use against cutaneous leishmaniasis.  相似文献   
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Female rats display a more robust behavioral response to acute cocaine administration than do male rats. However, a clear understanding of the biological mechanisms underlying these differences remains elusive. The present study investigated whether sexual dimorphisms in cocaine-induced motor behavior might be based on monoaminergic levels and/or cocaine pharmacokinetics. An acute injection of cocaine (5, 15, 20 or 30 mg/kg) or saline was administered to male and female rats, and behavioral activity was monitored for 3 h. Following acute cocaine or saline administration motor behavior varied according to dose and sex; overall, female rats displayed greater rearing counts and stereotypic scores, greater total locomotor counts at 15, 20, and 30 mg/kg of cocaine, and greater ambulatory counts at 20 and 30 mg/kg of cocaine than did male rats. Neurochemical determinations in post-mortem tissue showed that both male and female rats had increases in total dopamine (DA) in the caudate putamen (CPu) 15 min following cocaine administration. Additionally, male rats had a decrease in dihydroxyphenylacetic acid (DOPAC)/DA turnover. Female rats showed significant reductions in total levels of DA, DOPAC, HVA, serotonin (5-HT), 5-hydroxyindole acetic acid (5-HIAA), and DOPAC/DA turnover in the nucleus accumbens (NAc). Male rats displayed a reduction only in DOPAC/DA turnover and increases in 5-HT in the NAc following cocaine administration. Furthermore, sex differences in cocaine metabolism were observed where females had greater brain/blood levels of norcocaine and ecgonine methyl ester while male rats had higher blood levels of benzoylecgonine. These results suggest that sex differences in the behavioral responses to cocaine administration could be explained in part by intrinsic differences in both monoaminergic levels and metabolic processes.  相似文献   
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The aim of this study was to determine the effect of supplementation with 50,000 IU/monthly vitamin D for 1 yr on breast density in Iranian women. Methods: This double-blind, placebo-controlled, single center clinical trial was conducted among 400 women aged 40 yr and older. Participants were allocated to 2 groups. Group 1 received vitamin D (Cholecalciferol) 50,000 IU in tablet form, monthly, for 1 yr. Group 2 received vitamin E 400 IU in tablet form, monthly, for the same period of time. Participants had follow-up clinic visits every 6 mo and received an annual mammogram. Results: Final data were evaluated based on 216 and 194 women in the vitamin D and control groups. The mean decrease in mammographic density was ?5.01%(95% CI, ?9.9% to ?0.01%) and ?2.34 %(95% CI, ?6.84% to ?2.15%) in the vitamin D and control groups, respectively. There was no significant association between vitamin D consumption and breast density after 1 yr (OR = 0.7, 95% CI, 0.46 to 1.06; P = 0.1).Similar results were observed when multivariate model of logistic regression analysis was performed. Conclusions: This study showed that monthly consumption of 50,000 IU of vitamin D supplementation for 1 yr did not affect breast density.  相似文献   
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The present study examined mu and delta opioid analgesia, receptor binding, and receptor mRNA levels in lines of mice from two selective breeding projects of relevance to opioid analgesia. Large differences were observed in the analgesic potency of [ -Ala2, NMPhe4, Gly-ol]enkephalin (DAMGO), [ -Pen2,5]enkephalin (DPDPE), and [ -Ala2]deltorphin II (DELT), selective mu, delta1, and delta2 opioid receptor agonists, respectively, in mice selectively bred for high (HA) and low (LA) swim stress-induced analgesia (SIA). HAR and LAR mice, selectively bred for high and low levorphanol analgesia, respectively, display equally large differences in their analgesic sensitivity to DAMGO, modest differences in sensitivity to DPDPE, and no differences in sensitivity to DELT. These sizable genotypic differences in analgesic potency were accompanied by HA/LA and HAR/LAR differences in whole-brain homogenate [3H]DPDPE and/or [3H]DELT, but paradoxically not [3H]DAMGO, binding. Solution hybridization of mRNA extracts encoding mu (MOR-1) or delta (DOR-1) opioid receptors indicated some regional differences in gene expression between high and low lines. Surprisingly, differences in these in vitro markers were often in the direction of LAR>HAR. The present data indicate that selection for either SSIA or levorphanol analgesia produces differential effects on mu and delta opioid analgesia that are accompanied by alterations on in vitro assays, the significance of which remains to be determined. The data are discussed with regard to the utility of in vitro biological markers and genetic models of analgesia.  相似文献   
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