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Normal and streptozotocin-induced diabetic rats were fed the control high starch-diet or a high fatdiet supplemented with or without sodium orthovanadate (1.5 mg/g diet) for six weeks. Plasma glucose, insulin and triacylglycerol levels and the activities of hepatic glycogen synthase, phosphorylase, glucose-6-phosphate dehydrogenase, malic enzyme, and ATP-citrate lyase were measured in these eight groups of rats. The high fat-diet increased the levels of insulin (P<0.05) and triacylglycerol (P<0.01) in plasma and decreased the activities (P<0.001) of phosphorylase (active from and total) and the lipogenic enzymes. Vanadate supplementation led to significant (P<0.001) decreases in the elevated insulin and triacylglycerol levels whereas the enzyme activities remained unaffected. Diabetes and fat diet in combination caused 3.7-fold increases in plasma glucose and triacylglycerol levels and vanadate decreased them by 58% and 74% respectively. Vanadate improved the activities of hepatic glycogen metabolizing and lipogenic enzymes in diabetic rats when they were fed on control starch-diet but not with high fat-diet. This study shows that vanadate normalizes hyperinsulinemia and hypertriglyceridemia but not the defective hepatic glycogen metabolism in high fat-fed rats.  相似文献   
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A new method was developed to purify partially an orally active hypoglycemic fraction from the unripe fruits ofMomordica charantia Linn. The residue after centrifugation of the fruit juice was extracted with ethanol and the concentrated ethanolic extract was further extracted with diethyl ether. In normal rabbits after oral administration, the ether extract at a dose of 0.75 g/kg body wt decreased the fasting blood glucose by 26% (P<0.01). It was compared with charantin, the isolation procedure of which led to loss of hypoglycemic activity many times. Our new method of isolation is simple and the hypoglycemic effect is retained more consistently after purification.  相似文献   
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In recent years, there have been increasing calls from the government and other organizations to provide easy public access to student evaluations of teaching. Indeed, the increasing ease of displaying and viewing large quantities of information, and competition among universities and majors for students, makes it likely that an era of greater transparency of this type of information is at hand. While students’ evaluation of teaching (SET) is one quantitative metric that rates the instructor, it may be influenced by factors that are often beyond the instructor's control. In this study, we analyze a longitudinal data set from both engineering and business schools of a large public university, and identify factors that influence SET. We show which factors have the highest influence on overall SET scores, and contrast these between engineering and business colleges. Colleges within the same university may have differences in the factors affecting SET, and recognition of this is important in effectively and fairly evaluating SET scores. We also provide recommendations regarding information that should be displayed along with the SET, particularly when SET scores are made public, so that instructors are not unduly penalized when their evaluations can be influenced by factors over which they have no control.  相似文献   
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Open Access and the Developing World   总被引:2,自引:0,他引:2  
Till about 15 years ago, almost all information exchange among scientists and scholars was mediated by print and even then researchers in the developing countries were at a great disadvantage as their libraries did not have the resources to subscribe in comparison with even a small fraction of journals libraries in advanced countries. But the Internet and the World Wide Web initially exacerbated the gap between the rich and the poor countries, as many poor countries were slow to acquire these technologies and the infrastructure (especially bandwidth). Soon it became clear that thanks to these technologies we now have the unprecedented opportunity of having a level playing field in the matter of accessing scientific and scholarly information. Transforming this opportunity into reality is entirely in the hands of the researchers themselves. Imagine a world where every scientist places his/ her research papers, which (s)he wants to give away so others can read and make use of, in a public archive. Anyone anywhere in the world, of course having an Internet connection, can access, download, and read those papers. This is a win-win situation for all: the reader gets to read what he wants to read at very little cost; the author gains greater visibility for his work and the work reported is likely to have greater impact than if it were to be made available only through a toll-access journal. Although the logic is so simple, in reality such archives were not coming up for a very long time. In spite of the fact that computer scientists and physicists had shown about 15 years ago the great advantages of such archives. Recent studies by Alma Swan and others have shown that a very large proportion of scientists are not aware of open access and therefore what we need is focused advocacy. Even among those who know of OA, many are not depositing their papers in archives but say they would if they are asked by their bosses or their funding agencies. Clearly the ball is in the court of scientists and policy makers. OA is especially advantageous to the developing countries as the current access to literatures is poorest in these countries.  相似文献   
5.
To investigate the effects of antiphospholipid antibodies on establishment of pregnancy and changes in hormones such as estradiol-17ß (E2) and progesterone (P) levels in circulation. Hence, mice were immunized with human β2-Glycoprotein I (β2GPI) and the effect of these antibodies on fetuses weight, placental obsrvation, Serum levels of P and E2 in pregnant mice, hematological were observed. Immunization of mice with human β2-GPI resulted in elevated levels of antiphospholipid antibodies. The experimentally induced antiphospholipid syndrome mouse showed higher rate of fetal resorption, low number of viable fetuses, and “placental abnormalities”. In these animals, serum E2 and P levels were reduced significantly. In addition, the blood cell variation among APS induced and control mice were determined. No significant variations were observed in number of Red Blood Cell count, White Blood Cell count and Hemoglobin content, while platelet number was significantly reduced as compared to control. These results clearly demonstrate that human β2-GPI might be involved in causing gestational failure in APS by exerting their effect on serum hormones.  相似文献   
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A novel light scattering technique for mapping metal surface corrosion is presented and its results on copper exposed to atmosphere are reported. The front end of the instrument is made up of a sensor module comprising a thin beam light emitting diode (LED) illuminating a small spot on the metal surface, and a matched pair of photodetectors, one for capturing the reflected light and the other for sampling the scattered light. The analog photocurrent signals are digitized and processed online by a per- sonal computer (PC) to determine the corrosion factor defined in terms of the two current values. By scanning the sample surface using the light beam and by computing the corrosion factor values simultaneously, a three dimensional graph and a two dimensional contour map are generated in the PC using Matlab tools. The values of the corrosion factor measured in different durations of exposure to atmosphere, which obey a bilogarithmic law, testify to the validity of our mathematical model.  相似文献   
8.
The difference between the advanced and developing countries in the matter of access to information for research has been continually increasing. The advent of the Internet and electronic sources of information has not only exacerbated the gap but also led to the exclusion of developing country researchers from taking part as equal partners in publishing, refereeing, and in international collaboration. If handled imaginatively, the very same technologies can help bridge the information gap between the rich and the poor countries and help improve research productivity worldwide. Many initiatives that are already in place are described and suggestions are given on steps to be taken by developing country researchers.  相似文献   
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