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Yangxueqingnao particles inhibit rat vascular smooth muscle cell proliferation induced by lysophosphatidic acid 总被引:1,自引:0,他引:1
Cai W Xu Y Chen JZ Huang SR Lu ZY Wang ZK 《Journal of Zhejiang University. Science. B》2005,6(9):892-896
Objective: To observe the effect of Yangxueqingnao particles on rat vascular smooth muscle cell (VSMC) proliferation induced by lysophosphatidic acid (LPA). Methods: The amount of3H-TdR (3H-thymidine) admixed in cultured rat VSMC was measured and mitogen-activated protein kinase (MAPK) activity and lipid peroxidation end product malondialdehyde (MDA)content of the VSMC were assayed. Results: 1×10-9, 1×10-8, 1×10-7 mol/L LPA in a concentration dependent manner, induced the amount of 3H-TdR admixed, MAP kinase activity, and MDA content of the cultured rat VSMC to increase. However, 5%, 10%,and 15% Yangxueqingnao serum preincubation resulted in a decrease of 23.0%, 42.0%, and 52.0% (P<0.01) respectively in the amount of 3H-TdR admixed, a decline in VSMC MAP kinase activity of 13.9% (P<0.05), 29.6% (P<0.01), and 48.9% (P<0.01)respectively, and also, a decrease in MDA content of VSMC of 19.4%, 24.7%, and 43.2% (P<0.01) respectively, in the 1×10-7mol/L LPA-treated VSMC. Conclusions: LPA activates the proliferation and lipid peroxidation of VSMC in a concentration dependent manner. The LPA-induced VSMC proliferation is related to the activity of MAP kinases, enzymes involved in an intracellular signalling pathway. The results of the present study showed that Yangxueqingnao particles can effectively inhibit LPA-induced VSMC proliferation, MAP kinase activation, and reduce lipid peroxidative lesion. 相似文献
23.
陆英中乌索酸的分离制备及HPLC分析(Ⅲ) 总被引:3,自引:2,他引:3
目的:分离制备陆英中的乌索酸,并建立其含量测定方法.方法:采用“醇提凝析法”分离制备乌索酸,HPLC法测定其含量,色谱柱为Symmetry Shield RP18,流动相为甲醇-水(88:12),流速1ml/min,检测波长220nm,柱温25℃.结果:乌索酸在4.6~23.0μg范围内线性关系良好(r=0.9999),平均回收率为99.82%(RSD为0.75%).结论:“醇提凝析法”分离制备乌索酸工艺先进,实用可行;HPLC法测定乌索酸含量准确、可靠,可用于乌索酸含量测定分析。 相似文献
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Phytoremediation is emerging as a potential cost-effective solution for remediation of contaminated soils, and bioavailability
of metal in the soil for plant uptake is an important factor for successful phytoremediation. This study aimed at investigating
the ability of EDTA and citric acid for enhancing soil bioavailability of Cu and phytoremediation by Elsholtzia splendens
in two types of soils contaminated with heavy metals [i.e. mined soil from copper mining area (MS), and paddy soil (PS) polluted
by copper refining]. The results showed that addition of 2.5 mmol/kg EDTA significantly increased the H2O extractable Cu concentration from 1.20 to 15.78 mg/kg in MS and from 0.26 to 15.72 mg/kg in PS, and that shoot Cu concentration
increased 4-fold and 8-fold as compared to the control. There was no significant difference between the treatment with 5.0
mmol/kg EDTA and that with 2.5 mmol/kg EDTA, probably because that 2.5 mmol/kg EDTA was enough for elevating Cu bioavailability
to the maximum level. As compared with the control, citric acid had no marked effect on both soil extractable Cu and shoot
Cu concentration or accumulation. The results indicated that EDTA addition can increase the potential and efficiency of Cu
phytoextraction byE. splendens in polluted soils.
Project supported by the National Natural Science Foundation of China (No. 29977017) and the Science and Technology Ministry
of China (No. 2002CB410804) 相似文献
26.
林松竹 《中国教育科研与探索》2006,(5):17-19
本文进行了硫酸、对甲苯磺酸、氨基磺酸、强酸性阳离子交换树脂、六水三氯化铁、二水二氯化锡、十八水硫酸铝、十二水合硫酸铁铵、一水硫酸氢钠、固体超强酸、杂多酸和沸石分子筛等催化剂催化合成丁酸异戊酯的比较研究。 相似文献
27.
G. N. Raval L. J. Parekh D. D. Patel F. P. Jha R. N. Sainger P. S. Patel 《Indian journal of clinical biochemistry : IJCB》2004,19(2):60-71
Sialic acid, the end moieties of the carbohydrate chains are biologically important and essential for functions of glycoconjugates
and are reported to be altered in cancer patients. Two hundred and twenty five breast cancer (BC) patients, 100 patients with
benign breast disease (BBD) and 100 healthy females (controls) were enrolled for the study. Eight hundred and twenty four
follow-up samples of 225 breast carcinoma patients were also evaluated. The association of sialic acid forms, sialyltransferase
and α-2–6 sialoproteins levels with presence and extent as well as prognosis of breast carcinoma was studied. Serum sialic
acid forms and sialyltransferase revealed significantly elevated levels among untreated breast cancer patients as compared
to the controls, patients with BBD as well as cancer patients in remission. Non-responders showed comparable levels of the
markers with those found in breast cancer patients at the time of diagnosis. Higher levels of sialic acid forms at diagnosis
were associated with poor prognosis. A positive correlation between serum levels of different forms of sialic acids and extent
of malignant disease was observed. The changes in serum proteins with terminal α-2–6 sialic acid correlated well with alterations
in the levels of sialic acid forms and sialyltransferase. Malignant tissues showed elevated levels of sialic acid and sialyltransferase
as compared to surrounding normal tissues.
The results suggested potential utility of these markers in evaluation of clinical outcome. 相似文献
28.
Lakshmi Lavanya Reddy Swarup A. V. Shah Alpa J. Dherai Chandrashekhar K. Ponde Tester F. Ashavaid 《Indian journal of clinical biochemistry : IJCB》2016,31(1):87-92
Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP. 相似文献
29.
Response surface methodology (RSM) was used to optimize the fermentation medium for enhancing pyruvic acid production by Torulopsis glabrata TP19. In the first step of optimization, with Plackett-Burman design, ammonium sulfate, glucose and nicotinic acid were found to be the important factors affecting pyruvic acid production significantly. In the second step, a 23 full factorial central composite design and RSM were applied to determine the optimal concentration of each significant variable. A second-order polynomial was determined by the multiple regression analysis of the experimental data. The optimum values for the critical components were obtained as follows: ammonium sulfate 0.7498 (10.75 g/L), glucose 0.9383 (109.38 g/L) and nicotinic acid 0.3633 (7.86 mg/L) with a predicted value of maximum pyruvic acid production of 42.2 g/L. Under the optimal conditions, the practical pyruvic acid production was 42.4 g/L. The determination coefficient (R^2) was 0.9483, which ensures adequate credibility of the model. By scaling up fermentation from flask to jar fermentor, we obtained promising results. 相似文献
30.