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51.
Pankaj Abrol Neeraj Sharma Harbans Lal 《Indian journal of clinical biochemistry : IJCB》1997,12(2):125-127
Serum vitamin E and cholesterol concentrations were measured in 50 children with protein energy malnutrition (PEM) and results
were compared with a group of 50 normal controls. Mean serum vitamin E concentration as well as vitamin E/cholesterol ratio
were found to be reduced in children with PEM while their mean serum cholesterol level was not significantly different from
the control group. Data suggest that the reduced levels of serum vitamin E in PEM may be a result of malnutrition per se. 相似文献
52.
Abana, a herbal preparation of Himalaya Drug Co. significantly increases HDL—cholesterol and lowers LDL—cholesterol. Moreover, it antagonises the HDL lowering effect of metoprolol. 相似文献
53.
Lotka's law and institutional productivity 总被引:1,自引:0,他引:1
The present study aims at determining the applicability of Lotka's law, negative binomial distribution and lognormal distribution for institutional productivity, in the same way as it is to authors and their productivity in the field of engineering sciences and the patents filed by industrial firms in laser S&T. The study indicates that non of the three distributions are applicable for institutional productivity in engineering sciences. However, Lotka's law holds good for full as well as truncated set of data for the patents filed by industrial firms. 相似文献
54.
55.
P. K. Rai D. Jaiswal S. Mehta D. K. Rai B. Sharma Geeta Watal 《Indian journal of clinical biochemistry : IJCB》2010,25(2):175-181
This study deals with the effects of freeze dried rhizome powder of Curcuma longa (C. longa) dissolved in milk on normal as
well as diabetic models. Diabetes of type II and type I was within 3 days of a single administration of doses of 45 and 65
mg kg−1 of streptozotocin respectively. Various parameters such as blood glucose levels, triglycerides, total cholesterol, high density
lipoprotein, very low density lipoprotein, low density lipoprotein, serum glutamic oxaloacetic transaminase, serum glutamic
pyruvate transaminase, alkaline phosphatase, creatinine, hemoglobin, urine protein and urine sugar in addition to body weight
were taken in to consideration and were analyzed after administration of variable doses of rhizome powder. The dose of 200
mg kg−1 was identified as the most effective dose as it increased HDL, Hb and bw (P<0.05) with significant decrease in the levels
of blood glucose, lipid profile and hepatoprotective enzymes (P<0.001). 相似文献
56.
Singh PP Chandra A Mahdi F Roy A Sharma P 《Indian journal of clinical biochemistry : IJCB》2010,25(3):225-243
The antioxidants are essential molecules in human system but are not miracle molecules. They are neither performance enhancers
nor can prevent or cure diseases when taken in excess. Their supplemental value is debateable. In fact, many high quality
clinical trials on antioxidant supplement have shown no effect or adverse outcomes ranging from morbidity to all cause mortality.
Several Chochrane Meta-analysis and Markov Model techniques, which are presently best available statistical models to derive
conclusive answers for comparing large number of trials, support these claims. Nevertheless none of these statistical techniques
are flawless. Hence, more efforts are needed to develop perfect statistical model to analyze the pooled data and further double
blind, placebo controlled interventional clinical trials, which are gold standard, should be implicitly conducted to get explicit
answers. Superoxide dismutase (SOD), glutathione peroxidase and catalase are termed as primary antioxidants as these scavenge
superoxide anion and hydrogen peroxide. All these three enzymes are inducible enzymes, thereby inherently meaning that body
increases or decreases their activity as per requirement. Hence there is no need to attempt to manipulate their activity nor
have such efforts been clinically useful. SOD administration has been tried in some conditions especially in cancer and myocardial
infarction but has largely failed, probably because SOD is a large molecule and can not cross cell membrane. The dietary antioxidants,
including nutrient antioxidants are chain breaking antioxidants and in tandem with enzyme antioxidants temper the reactive
oxygen species (ROS) and reactive nitrogen species (RNS) within physiological limits. Since body is able to regulate its own
requirements of enzyme antioxidants, the diet must provide adequate quantity of non-enzymic antioxidants to meet the normal
requirements and provide protection in exigent condition. So far, there is no evidence that human tissues ever experience
the torrent of reactive species and that in chronic conditions with mildly enhanced generation of reactive species, the body
can meet them squarely if antioxidants defense system in tissues is biochemically optimized. We are not yet certain about
optimal levels of antioxidants in tissues. Two ways have been used to assess them: first by dietary intake and second by measuring
plasma levels. Lately determination of plasma/serum level of antioxidants is considered better index for diagnostic and prognostic
purposes. The recommended levels for vitamin A, E and C and beta carotene are 2.2–2.8 μmol/l; 27.5–30 μmol/l; 40–50 μmol/l
and 0.4–0.5 μmol/l, respectively. The requirement and recommended blood levels of other dietary antioxidants are not established.
The resolved issues are (1) essential to scavenge excess of radical species (2) participants in redox homeostasis (3) selective
antioxidants activity against radical species (4) there is no universal antioxidant and 5) therapeutic value in case of deficiency.
The overarching issues are (1) therapeutic value as adjuvant therapy in management of diseases (2) supplemental value in developing
population (3) selective interactivity of antioxidant in different tissues and on different substrates (4) quantitative contribution
in redox balance (5) mechanisms of adverse action on excess supplementation (6) advantages and disadvantages of prooxidant
behavior of antioxidants (7) behavior in cohorts with polymorphic differences (8) interaction and intervention in radiotherapy,
diabetes and diabetic complications and cardiovascular diseases (9) preventive behavior in neurological disorders (10) benefits
of non-nutrient dietary antioxidants (11) markers to assess optimized antioxidants status (12) assessment of benefits of supplementation
in alcoholics and heavy smokers. The unresolved and intriguing issues are (1) many compounds such as vitamin A and many others
possessing both antioxidant and non-antioxidant properties contribute to both the activities in vivo or exclusively only to
non-antioxidant activity and (2) since human tissues do not experience the surge of FR, whether there is any need to develop
stronger synthetic antioxidants. Theoretically such antioxidants may do more harm than good. 相似文献
57.
58.
Anita Devi Ritu Singh Rajni Dawar Sanjay Tyagi 《Indian journal of clinical biochemistry : IJCB》2017,32(2):235-238
Association of cholesteryl ester transfer protein (CETP) Gene -629C/A Polymorphism with angiographically proven atherosclerosis CETP gene has been linked to CAD risk via its role in HDL and LDL metabolism. There is no agreement of whether CETP is atherogenic or not. Furthermore, various genotypes of CETP gene have been associated with CETP levels and thus with atherosclerosis risk. Our aim was to study the association of CETP -629C/A gene polymorphism with CETP and HDL levels and their association if any with atherosclerosis. Study population consisted of angiographically documented 50 cases with coronary artery atherosclerosis and 50 controls negative for atherosclerosis of coronary artery. Serum lipid profile was measured on SYNCHRON CX-9 using standard kits. Serum CETP levels were measured by ELISA method. CETP -629C/A gene polymorphism was studied using PCR–RFLP method. There was no significant difference in lipid profile of the two groups. However, serum CETP level was significantly higher (46.44 ± 21.75 ng/ml) in cases than controls (37.10 ± 21.92 ng/ml) with p value =0.035. The frequency of -629A allele was higher (0.85) in cases than that of controls (0.81). Homozygosity of A allele was more in subjects with atherosclerosis of coronary artery. We conclude that CETP is atherogenic and could be used as atherogenic risk predictor in angiographically proven atherosclerosis. Also A allele of -629C/A polymorphism is more prevalent in cases; indicating its effect on expression of CETP gene. 相似文献
59.
60.
Interactivity, group learning and student engagement are accepted as key features of social constructivist learning theories.
The challenge is to understand the interplay between such features in different learning environments. This study focused
on the qualitative differences between two interventions—small-groups and whole-class discussions. In both interventions,
three short video slices on the abstract topic ‘the physics of superconductivity’ were interspersed with the different discussion
styles. The video slices are based on the Bruner stages. Twenty-nine first year university physics students completed a pre-test,
underwent the intervention and completed a post-test. The remainder of the data were collected from student drawings, video
recordings, observer notes and facilitator feedback. Results indicate that the use of the video slices in both interventions
were successful in changing students’ understandings of superconductivity. However, the small groups treatment tended to facilitate
questioning, meaning-making and subsequent changes of ideas more so than the whole class discussions. Implications for research
and practice are discussed. 相似文献