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91.
M. Hussin A.A. Hamid S. Mohamad N. Saari F. Bakar S.P. Dek 《Journal of food science》2009,74(2):H72-H78
ABSTRACT: A study was carried out to investigate the effects of Centella asiatica leaf on lipid metabolism of oxidative stress rats. The rats were fed 0.1% hydrogen peroxide (H2 O2 ) with either 0.3% (w/w) C. asiatica extract, 5% C. asiatica powder (w/w), or 0.3% (w/w) α-tocopherol for 25 wk. Results of the study showed that C. asiatica powder significantly ( P < 0.05) lowered serum low-density lipoprotein compared to that of control rats (rats fed H2 O2 only). At the end of the study C. asiatica -fed rats were also found to have significantly ( P < 0.05) higher high-density lipoprotein and lower triglyceride level compared to rats fed only normal diet. However, cholesterol level of rats fed both C. asiatica extract and powder was found to be significantly ( P < 0.05) higher compared to that of control rats. It was interesting to note that consumption of C. asiatica significantly decreased body and liver weights of the rats. Histological examinations revealed no obvious changes in all rats studied. Quantitative analysis of C. asiatica leaf revealed high concentration of total phenolic compounds, in particular, catechin, quercetin, and rutin. 相似文献
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Epidemiological and experimental studies have suggested that high dietary fat intake of mice is associated with many physically degenerative diseases. Since oxidative stress and abnormal lipid metabolism have been speculated to be critical mechanisms underlying degenerative diseases, we hypothesized that a high-fat (HF) diet might induce oxidative stress or lipid oxidation and subsequently contribute to the high risk of some diseases such as cardiovascular and cerebrovascular ones. To test this hypothesis, male kunming mice were placed on either a HF diet or a normal laboratory diet for 30 consecutive days. This investigation demonstrated that blood fat [low density lipoprotein (LDL), total cholesterol (TC), triacylglycerols (TAG), high density lipoprotein (HDL)], blood sugar (blood glucose and liver glycogen) and oxidative stress (activities of antioxidant enzymes and levels of non-enzymic antioxidants) of mice fed high-fat diet (group II) were significantly increased or decreased (P < 0.05, P < 0.01) when compared with the control group (I). The present study revealed that HF diet induced oxidative stress and provided novel evidence regarding the link between high dietary fat and increased risk of degenerative diseases. The administration of Lycium barbarum polysaccharides did not show any effect on the body weight of the experimental mice, but significantly decreased the levels of LDL, TC, TAG, blood glucose and thiobarbituric acid reactive substances (TBARS) or increased the activities of antioxidant enzymes (P < 0.05, P < 0.01) when compared with mice in HF group (II). These findings were further supported by significantly increased non-enzymic antioxidants levels (P < 0.05, P < 0.01), suggesting that L. barbarum polysaccharides showed a noticeable inhibition against lipid oxidation induced by free radicals caused by HF diet intake (groups III, IV, V) on the basis of their antioxidant activities. 相似文献
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硬件设计借鉴软件设计的经验意义重大。首先简要介绍了状态机理论,并给出了用硬件来实现程序算法的步骤以及状态图的化简原则,然后列举了一个求最大公因数的例子来详细阐述这种方法以及实现步骤。给出的方法,通用性强,方便借鉴成熟的软件设计技术,可以大大提升数字系统的设计效率。 相似文献
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Annurca (Malus pumila Miller cv. Annurca) apple as a functional food for the contribution to a healthy balance of plasma cholesterol levels: results of a randomized clinical trial 下载免费PDF全文
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Postprandial triglyceride-rich lipoproteins (TRL) levels are a predictor for coronary atherosclerosis. The aim of the study was to compare fasting high density lipoprotein (HDL) cholesterol, plasma lipoprotein lipase (LPL) activity, and postprandial TRL between elderly survivors of myocardial infarction (MI) and healthy controls. A case-control study was performed in 44 elderly patients 65-85 years of age with a previous history of MI and 43 age- and sex-matched healthy controls. Each participant underwent physical examination and was given a standard oral fat load with subsequent blood sampling over the next 8 h. Total and chylomicron triglycerides were assessed by area under the curve (AUC), incremental are under the curve (AUCi) and triglyceride response (TGR). Elderly MI patients had significantly lower postheparin LPL activity (87.4 +/- 36.9 mU/ml) (mean +/- 1 SD) than healthy controls (106.0 +/- 29.0 mU/ml) (P = 0.014). Decreased postheparin LPL activity was accompanied by significant increased and delayed clearance of postprandial TRL. Fasting HDL cholesterol was significantly lower in elderly MI patients than controls (1.45 +/- 0.32 and 1.66 +/- 0.47 mmol/l, respectively, P = 0.048). Multiple regression analysis revealed postheparin LPL activity as an independent predictor for postprandial TRL and fasting HDL cholesterol. Logistic regressions analysis revealed HDL cholesterol, triglycerides measured 2 h after the oral fat load, and postheparin LPL activity as independent predictors for MI. Our findings indicate that decreased fasting HDL cholesterol is associated with increased postprandial triglyceridemia which could be a target for life-style and therapeutic interventions in patients at risk for cardiovascular disease. 相似文献
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Li Tian Xinwei Wu Mingde Fu Yanhua Xu Lianqun Jia 《European Journal of Lipid Science and Technology》2008,110(10):879-886
Background and aims: To investigate the impact of plasma apoA‐II concentrations on the alteration of HDL subclass distribution, and the cooperative effect of apoA‐I and apoA‐II on it. Methods and results: The apoA‐I contents of plasma HDL subclasses were quantified by two‐dimensional gel electrophoresis associated with immunodetection for 292 Chinese people. These subjects were divided according to the mean ± 1 SD of apoA‐II and apoA‐I levels as two cut‐points, respectively. Compared with the low‐apoA‐II group, the apoA‐I contents of HDL3a (in the high group), HDL3b, and HDL2b increased strikingly, both in the middle‐ and high‐apoA‐II group. The apoA‐I contents of all HDL subclasses increased progressively when the apoA‐I and apoA‐II levels simultaneously or the apoA‐I/apoA‐II ratio increased, and in comparison to the low‐apoA‐I–A‐II levels group, the apoA‐I contents of HDL2b (115%) increased more significantly than those of preβ1‐HDL (39%) in the high‐apoA‐I–A‐II levels group. Multiple analyses also indicated that the three HDL subclasses, HDL3a, HDL3b and HDL2b, were independently predicted by apoA‐II. Conclusion: Excess apoA‐II can cause the accumulation of both large‐sized HDL2b and small‐sized HDL3, which implies that apoA‐II plays a double role in the HDL maturation metabolism. Meanwhile, the degree of HDL2b increased significantly relative to that of preβ1‐HDL when apoA‐I and apoA‐II levels were elevated simultaneously, suggesting that the maturation and metabolism of HDL might be promoted and reverse cholesterol transport might be enhanced. 相似文献