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441.
In this study,nano-biocomposites of polycaprolactone(PCL)as the matrix and different amounts of nanofluorapatite(nFA)(0,10,20 and 30 wt.%)as the reinforcement w...  相似文献   
442.
The strain of Acremonium strictum PTCC 5282 was applied to investigate the biotransformation of androst-1,4-dien-3,17-dione (I; ADD). Microbial products obtained were purified by preparative TLC and the pure metabolites were characterized on the basis of their spectroscopic features (13C NMR, 1H NMR, FTIR, MS) and physical constants (melting points and optical rotations). The 15α-Hydroxyandrost-1,4-dien-3,17-dione (II), 17β-hydroxyandrost-1,4-dien-3-one (III), androst-4-en-3,17-dione (IV; AD), 15α-hydroxyandrost-4-en-3,17-dione (V), 15α,17β-dihydroxyandrost-1,4-dien-3-one (VI) and testosterone (VII) were produced during this fermentation. Formation of the 15α,17β-dihydroxy derivative of ADD is reported for the first time during steroid biotransformation. The bioconversion reactions observed were 1,2-hydrogenation, 15α-hydroxylation and 17-ketone reduction. From the time course profile of this biotransformation, ketone reduction and 1,2-hydrogenation were observed from the first day of fermentation while 15α-hydroxylation occurred from the third day. Optimum concentration of the substrate, which gave the maximum bioconversion efficiency, was 0.5 mg ml−1 in one batch. The highest yield of the microbial products recorded in this work was achieved within the pH range 6.5–7.3 and at the temperature of 27 °C.  相似文献   
443.

Background

Coronary artery disease is the leading cause of death in industrialized countries and most patients with diabetes die from complications of atherosclerosis. The objective of this study was to determine the presence of diabetes mellitus and other conventional coronary heart disease risk factors (cigarette smoking, hypertension and hyperlipidemia) in patients with acute coronary events in an Iranian population.

Methods

The study included 514 patients with unstable angina or myocardial infarction (MI) out of 720 patients admitted to CCU ward of a general hospital from March 2003 to March 2005. History of diabetes, hypertension and cigarette smoking, demographic indices, coronary heart disease and diabetes mellitus treatment, myocardial enzymes, serum triglycerides (TG) and cholesterol and fasting and non fasting blood glucose levels and HbA1C of diabetics were recorded of admission sheets. The data were structured to appropriate one way ANOVA, T tests, and chi square test with SPSS 13 product for windows.

Results

Out of all patients 35.8% were female, 30% were diabetics (Duration 13.4 ± 8.7 years), 42% were smoker and 91% were hypertensive. Twenty four percent had MI and 76% had unstable angina. MI was significantly higher in diabetic patients (36.4% vs. 19.2%, P < 0.001). Location and extension of MI and myocardial enzymes did not differ between diabetics and non-diabetic patients. Diabetic patients were older than non diabetics (65 ± 11.6 vs. 59.7 ± 12.5 years, p < 0.05). Five (66.7%) out of 9 patients with fatal MI were diabetics (Odds Ratio = 2.98). Age, duration of diabetes and HbA1c levels, did not differ between diabetic patients with or without MI. Hypertension and current smoking was significantly higher in patients with MI compared to patients with unstable angina (p < 0.05). Serum TG, HDL-C, LDL-C and total cholesterol level did not differ between patients with MI and unstable angina. Diabetic patients compare to non diabetic patients were more hypertensive (96% vs. 88.7%, p < 0.005) and had higher serum triglyceride (TG over 200 mg/dl, 35.1% vs. 26.4, p <0.05). Diabetes was more frequent among women than men (36.4% vs. 26.4%, p < 0.05). Women were older than men (65 ± 11.6 vs. 59.2 ± 13 years, p < 0.005) and had higher total serum cholesterol (200 ± 41.8 vs. 192 ± 42.5 mg/dl, p < 0.05) and HDL-C levels (49.7 ± 22 vs. 40 ± 13 mg/dl, p < 0.005). Ninety seven percent of all patients had at least one of cardiovascular risk factors (hypertension, smoking, diabetes, high cholesterol and low HDL-cholesterol levels).

Conclusion

In this study 19 out of 20 patients with acute coronary event have at least one of conventional cardiac risk factors. Diabetes and hypertension are leading risk factors, which may directly or indirectly interfere and predict more serious complications of coronary heart disease.  相似文献   
444.
The effects of morphine, 1-aminocyclobutane-cis-1,3-dicarboxylic (ACBD; NMDA agonist) and 3-((R)2-carboxypiperazin-4-yl)-propyl-l-phosphoric acid (CPP; NMDA antagonist) and their concurrent therapy on rat submandibular secretory function were studied. Pure submandibular saliva was collected intraorally by micro polyethylene cannula from anaesthetized rats using pilocarpine as secretagogue. Intraperitoneal injection of morphine (6 mg/kg) induced significant inhibition of salivary flow rate, total protein, calcium, and TGF-beta1 concentrations. Administration of ACBD (10 mg/kg) and CPP (10 mg/kg) alone did not influence secretion of submandibular glands. In combination therapy, coadministration of CPP with morphine did not influence morphine-induced changes in salivary function while ABCD could restore all morphine-induced changes. In combination treatment, ACBD prevented morphine-induced reduction of flow rate, total protein, calcium, and TGF-beta1 and reached control levels. It is concluded that morphine-induced alterations in submandibular gland function are mediated through NMDA receptors.  相似文献   
445.
Aims Effects of insulin and ascorbic acid on expression of Bcl-2 family proteins and caspase-3 activity in hippocampus of diabetic rats were evaluated in this study. Methods Diabetes was induced in Wistar male rats by streptozotocin (STZ). Six weeks after verification of diabetes, the animals were treated for 2 weeks with insulin or/and ascorbic acid in separate groups. Hippocampi of rats were removed and evaluation of Bcl-2, Bcl-xL, and Bax proteins expression in frozen hippocampi tissues were done by SDS-PAGE electrophoresis and blotting. The Bcl-2, Bcl-xL, and Bax proteins bands were visualized after incubation with specific antibodies using enhanced chemiluminescences method. Caspase-3 activity was determined using the caspase-3/CPP32 Fluorometric Assay Kit. Results Diabetic rats showed increase in Bax protein expression and decrease in Bcl-2 and Bcl-xL proteins expression. The Bax/Bcl-2 and Bax/Bcl-xL ratios were found higher compared with non-diabetic control group. Treatments with insulin and/or ascorbic acid were resulted in decrease in Bax protein expression and increase in Bcl-2 and Bcl-xL proteins expression. The Bcl-2/Bax and Bcl-xL/Bax ratios were found higher in treated groups than untreated diabetic group. Caspase-3 activity level was found higher in diabetic group compared with non-diabetic group. Treatment with insulin and ascorbic acid did downregulated caspase-3 activity. Conclusions Our data provide supportive evidence to demonstrate the antiapoptotic effects of insulin and ascorbic acid on hippocampus of STZ-induced diabetic rats.  相似文献   
446.
To understand the influence of plant quality on intraguild predation and consequently on the suppression of a shared prey population as well as on plant yield, the interactions between Aphis gossypii Glover (Hemiptera: Aphididae) (shared prey), Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae) (intermediate predator), and Orius laevigatus Fieber (Hemiptera: Anthocoridae) (top predator) were investigated in 25‐day experiments on cucumber, Cucumis sativus L. (Cucurbitaceae) at various N fertilization levels (90, 150, and 190 p.p.m.) in microcosm set‐ups under greenhouse conditions. The final aphid population size was significantly affected by an interactive effect of N fertilization and predator application. Regardless of the N fertilization levels, O. laevigatus alone was more effective in aphid suppression than A. aphidimyza alone. In addition, the risk for aphids of being predated upon by both predators together was significantly reduced in the low and medium‐N fertilization levels, whereas it was additive in the high‐N fertilization treatment. The A. aphidimyza population was suppressed by O. laevigatus in both the 90 and 150 p.p.m. N treatments. However, there was no intraguild predation of O. laevigatus on A. aphidimyza at the 190 p.p.m. N level. Total plant yield depended on predator treatments and N fertilization levels, with the highest yield produced at the 150 p.p.m. N fertilization level in treatments with either O. laevigatus alone or with both predators together. Our results demonstrate that the weak asymmetric intraguild predation among A. aphidimyza and O. laevigatus does not influence the ability of both predators together to diminish bottom‐up effects on aphid populations and the yield losses associated with aphid infestations.  相似文献   
447.
Mixed‐dimensional perovskite solar cells combining 3D and 2D perovskites have recently attracted wide interest owing to improved device efficiency and stability. Yet, it remains unclear which method of combining 3D and 2D perovskites works best to obtain a mixed‐dimensional system with the advantages of both types. To address this, different strategies of combining 2D perovskites with a 3D perovskite are investigated, namely surface coating and bulk incorporation. It is found that through surface coating with different aliphatic alkylammonium bulky cations, a Ruddlesden–Popper “quasi‐2D” perovskite phase is formed on the surface of the 3D perovskite that passivates the surface defects and significantly improves the device performance. In contrast, incorporating those bulky cations into the bulk induces the formation of the pure 2D perovskite phase throughout the bulk of the 3D perovskite, which negatively affects the crystallinity and electronic structure of the 3D perovskite framework and reduces the device performance. Using the surface‐coating strategy with n‐butylammonium bromide to fabricate semitransparent perovskite cells and combining with silicon cells in four‐terminal tandem configuration, 27.7% tandem efficiency with interdigitated back contact silicon bottom cells (size‐unmatched) and 26.2% with passivated emitter with rear locally diffused silicon bottom cells is achieved in a 1 cm2 size‐matched tandem.  相似文献   
448.
A case of adamantinoma of the tibia metastatic to the lung is reported in which the metastatic lesion was initially diagnosed by pulmonary brushing cytology. The cytologic features, including clusters of small cells with either prominent nucleoli or spindle-shaped hyperchromatic nuclei, appear to be distinctive enough to differentiate this lesion from other metastatic malignant tumors of the lung.  相似文献   
449.
450.
1. Groups of lean and obese LA/N-cp and obese Type II diabetic SHR/N-cp rats were fed semisynthetic diets with or without the alpha-glucosidase inhibitor acarbose (ACB, 100 mg/kg diet, p.o.) from 8 until 15 weeks of age, and measures of fasting serum total cholesterol (TC), insulin (INS), and hepatic HMG-CoA synthase activity determined at the end of the study. 2. ACB was without marked effect on mean food intake in either strain or either phenotype, and resulted in less weight gain and decreased adipose mass in obese LA/N-cp rats. INS was greater in the obese than the lean phenotype of both strains, and ACB resulted in greater reductions in INS in obese LA/N-cp than in obese LA/N-cp rats. 3. Serum TC concentrations were greater in the obese than in the lean phenotype of both strains, and ACB resulted in decreases in TC in both strains and in lower beta:alpha lipoprotein cholesterol ratios in obese LA/N-cp rats. Liver HMG Co-A synthase activity was greater in lean than obese rats and ACB resulted in normalization of enzyme activity in obese LA/N-cp but not SHR/N-cp rats. 4. These results confirm the hypercholesterolemia which occurs in the obese phenotype of the corpulent rat strains, and indicates that ACB may bring about significant reductions in body weight and fatness, TC, and in improved beta:alpha lipoprotein ratios and HMG-CoA synthase activity in obesity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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