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131.
132.
In this study, magnetic nanoparticles functionalized with carboxylated β‐cyclodextrin (CM‐β‐CD; referred to Fe3O4@CM‐β‐CD) were synthesized and used for the efficient removal of cholesterol from milk and egg yolk via host–guest interactions. The results of Fourier‐transform infrared, X‐ray photoelectron spectroscopy, and thermogravimetric analysis indicated that the CM‐β‐CD was successfully conjugated to the surface of Fe3O4, and the amount of CM‐β‐CD attached on Fe3O4@CM‐β‐CD was determined to be 9.164%. The X‐ray diffraction and transmission electron microscopy data revealed that the process of CM‐β‐CD coating did not result in a phase change of the Fe3O4, and the Fe3O4@CM‐β‐CD nanoparticles were determined to have an average size of about 15 nm. The results of isotherm adsorption and kinetic properties indicated that CM‐β‐CD functionalization increased the cholesterol removal efficiency, and the characteristics of cholesterol adsorption on Fe3O4@CM‐β‐CD were fitted well with the Langmuir adsorption model and Lagergren pseudo‐1st‐order kinetic models. Furthermore, compared with the Fe3O4 nanoparticles, the functionalized Fe3O4@CM‐β‐CD nanoparticles exhibited greater cholesterol removal efficiency, and saponification of the milk and egg yolk was found to be beneficial for the cholesterol removal; using the Fe3O4@CM‐β‐CD nanoparticles, 98.8% and 94.6% of the cholesterol was extracted in 1 h from saponified milk and egg yolk, respectively, and the Fe3O4@CM‐β‐CD nanoparticles still displayed efficient cholesterol removal after 6 reuses. 相似文献
133.
耐胆酸盐、降胆固醇乳酸菌的筛选 总被引:8,自引:1,他引:8
从乳酸发酵制品和发酵菌剂中分离纯化获得了25株菌,通过显微镜形态观察、革兰氏染色反应和石蕊牛奶试验证实其中10株为乳酸菌。进一步比较了这些菌株和Streptococcus thermophilis,Lactobaccillus bulgaricus的胆酸盐耐受能力以及对牛奶中胆固醇的作用效果。结果表明,多数乳酸菌可耐受低质量分数(0.1%)的胆酸盐,可以不同程度的降低牛奶中的胆固醇含量;但在含有质量分数为0.3%胆酸盐时,只有少数乳酸菌对牛奶中降胆固醇的能力有所提高。 相似文献
134.
观察了三鹿降血脂奶粉调节血脂的作用。用Wistar品系雄性大鼠60只随机分为6组,全部饲以高脂饲料,在此基础上分别饲以蒸馏水、普通奶粉及3个不同剂量的降血脂奶粉。实验期45d,实验前后测量体重,并采用酶法测定血清总胆固醇(TC)、总甘油三酯(TG)及高密度脂蛋白胆固醇(HDL-C)。结果表明,实验前后的各组大鼠体重均明显增加,但各实验组间无显著性差异(P>0.05)。处理组大鼠血清TG水平显著低于对照组(P<0.05或P<0.01);高剂量降血脂奶粉组大鼠血清HDL-C水平显著高于对照组(P<0.05);各组大鼠血清TC水平则未见有显著性差异。结论,三鹿降血脂奶粉对实验大鼠体重无影响,但可以显著降低TG并可显著升高HDL-C水平。 相似文献
135.
添加剂W对酶的分离纯化造成很大困难,用异丙醇沉淀发酵液的同时加入(NH4)2SO4能够有效地破除乳化体系,去除添加剂W,酶收率达到90%.在pH值为8.0的条件下用SepharoseDEAEFastFlow离子交换透析酶液,比酶活从3.21U/mg提高到29.21U/mg,酶收率达70.1%. 相似文献
136.
6‐Dihydroparadol,a Ginger Constituent,Enhances Cholesterol Efflux from THP‐1‐Derived Macrophages 下载免费PDF全文
Dongdong Wang Verena Hiebl Angela Ladurner Simone L. Latkolik Franz Bucar Elke H. Heiß Verena M. Dirsch Atanas G. Atanasov 《Molecular nutrition & food research》2018,62(14)
1 Scope
Ginger is reported to be used for the prevention and treatment of cardiovascular diseases (CVD). Cholesterol efflux from macrophage foam cells is an important process in reverse cholesterol transport, whose increase may help to prevent or treat CVD. In this study, we investigated the effects of 6‐dihydroparadol from ginger on macrophage cholesterol efflux.2 Methods and results
We show that 6‐dihydroparadol concentration‐dependently enhances both apolipoprotein A1‐ and human plasma–mediated cholesterol efflux from cholesterol‐loaded THP‐1‐derived macrophages using macrophage cholesterol efflux assay. 6‐Dihydroparadol increases protein levels of both ATP‐binding cassette transporters A1 and G1 (ATP‐binding cassette transporter A1 [ABCA1] and ATP‐binding cassette transporter G1 [ABCG1]) according to Western blot analysis. The ABCA1 inhibitor probucol completely abolishes 6‐dihydroparadol‐enhanced cholesterol efflux. Furthermore, increased ABCA1 protein levels in the presence of 6‐dihydroparadol were associated with both increased ABCA1 mRNA levels and increased ABCA1 protein stability. Enhanced ABCG1 protein levels were only associated with increased protein stability. Increased ABCA1 protein stability appeared to be the result of a reduced proteasomal degradation of the transporter in the presence of 6‐dihydroparadol.3 Conclusion
We identified 6‐dihydroparadol from ginger as a novel promoter of cholesterol efflux from macrophages that increases both ABCA1 and ABCG1 protein abundance. This newly identified bioactivity might contribute to the antiatherogenic effects of ginger. 相似文献137.
Chang‐Che Chen Fen‐Pi Chou Yung‐Chyan Ho Wea‐Lung Lin Chin‐Pin Wang Erl‐Shyh Kao An‐Chung Huang Chau‐Jong Wang 《Journal of the science of food and agriculture》2004,84(15):1989-1996
Hibiscus sabdariffa L extract (HSE) is an aqueous extract of Hibiscus sabdariffa L flowers that is used as a local soft drink and medical herb in Taiwan. Oxidation of low‐density lipoprotein (LDL) has been shown to increase the incidence of atherosclerosis. In this study, we determined the antioxidative activity of HSE on LDL oxidation by examining relative electrophoretic mobilities (REM) and thiobarbituric acid‐reactive substances (TBARS). The data revealed an inhibitory effect of HSE on Cu2+‐mediated REM and TBARS. HSE exhibited a remarkable ability to reduce cholesterol degradation and ApoB fragmentation. Overall, HSE showed a high potency to inhibit the production of oxidized LDL induced by copper and, specifically, to reduce serum triglycerides in high‐fructose diet (HFD) fed rats and serum cholesterol in high‐cholesterol diet (HCD) fed animals. The levels of LDL and the ratio of LDL‐cholesterol (LDL‐C) to HDL‐cholesterol (HDL‐C) were reduced by HSE in both hyperlipidaemia models. Based on these findings, we suggest that HSE may be used to inhibit LDL oxidation and to prevent various types of hyperlipidaemia in HFD‐ or HCD‐fed rats. Copyright © 2004 Society of Chemical Industry 相似文献
138.
139.
140.
Fen Zhang Liang Qiu Xiongpeng Xu Zhengqi Liu Hui Zhan Xueying Tao Nagendra P. Shah Hua Wei 《Journal of dairy science》2017,100(3):1618-1628
The aim of this study was to select probiotic Enterococcus strains that have the potential to improve metabolic syndrome (MS). Ten Enterococcus strains isolated from healthy infants were evaluated for their probiotic properties in vitro, and Enterococcus faecium WEFA23 was selected due to its cholesterol removal ability (1.89 ± 0.07 mg/1010 cfu), highest glycodeoxycholic acid-hydrolase activity (1.86 ± 0.01 U/mg), and strong adhesion capacity to Caco-2 cells (17.90 ± 0.19%). The safety of E. faecium WEFA23 was verified by acute oral administration in mice, and it was found to have no adverse effects on general health status, bacterial translocation, and gut mucosal histology. Moreover, the bene?cial effects of E. faecium WEFA23 on high-fat diet-induced MS in rats were investigated, and we found WEFA23 signi?cantly decreased body weight, serum lipid levels (total cholesterol, triacylglycerols, and low-density lipoprotein cholesterol), blood glucose level, and insulin resistance in rats fed with a high-fat diet. This indicated that administration of E. faecium WEFA23 improved almost all key markers of MS, including obesity, hyperlipidemia, hyperglycemia, and insulin resistance. Our results supported E. faecium WEFA23 as a candidate for cholesterol-lowering dairy products and improvement of MS. Our research provided novel insights on Enterococcus as a strategy to combat MS. 相似文献