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991.
Binbin Tan Ying Zhang Tiantian Zhang Jinsong He Xueying Luo Xiqing Bian Jianlin Wu Chang Zou Yangzhi Wang Li Fu 《Biomedical chromatography : BMC》2020,34(10):e4922
Recent advances suggest that abnormal fatty acid metabolism highly correlates with breast cancer, which provide clues to discover potential biomarkers of breast cancer. This study aims to identify serum free fatty acid (FFA) metabolic profiles and screen potential biomarkers for breast cancer diagnosis. Gas chromatography–mass spectrometry and our in-house fatty acid methyl ester standard substances library were combined to accurately identify FFA profiles in serum samples of breast cancer patients and breast adenosis patients (as controls). Potential biomarkers were screened by applying statistical analysis. A total of 18 FFAs were accurately identified in serum sample. Two groups of patients were correctly discriminated by the orthogonal partial least squares–discriminant analysis model based on FFA profiles. Seven FFA levels were significantly higher in serum from breast cancer patients than that in controls, and exhibited positive correlation with malignant degrees of disease. Furthermore, five candidates (palmitic acid, oleic acid, cis-8,11,14-eicosatrienoic acid, docosanoic acid and the ratio of oleic acid to stearic acid) were selected as potential serum biomarkers for differential diagnosis of breast cancer. Our study will help to reveal the metabolic signature of FFAs in breast cancer patients, and provides valuable information for facilitating clinical noninvasive diagnosis. 相似文献
992.
Metabolites identification of Huo Luo Xiao Ling Dan in rat urine by UPLC coupled with electrospray ionization time‐of‐flight mass spectrometry 下载免费PDF全文
Fenrong Wang Yun Wu Yu Ai Qiaoxia Bian Wen Ma David Y.‐W. Lee Ronghua Dai 《Biomedical chromatography : BMC》2016,30(3):396-409
Huo Luo Xiao Ling Dan (HLXLD), a Chinese herbal formula, is used in folk medicine for the treatment of arthritis and other chronic inflammatory diseases. However, the in vivo integrated metabolism of its multiple components remains unknown. In this paper, an ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry (UPLC‐Q‐TOF‐MS) method was developed for detection and identification of HLXLD metabolites in rat urine at high and normal clinical dosages. The prototype constituents and their metabolites in urine were analyzed. The mass measurements were accurate within 8 ppm, and subsequent fragment ions offered higher quality structural information for interpretation of the fragmentation pathways of various compounds. A total of 85 compounds were detected in high dosages urine samples by a highly sensitive extracted ion chromatograms method, including 31 parent compounds and 54 metabolites. Our results indicated that phase 2 reactions (e.g. glucuronidation, glutathionidation and sulfation) were the main metabolic pathways of lactones, alkaloids and flavones, while phase I reactions (e.g. hydrogenation and hydroxylation) were the major metabolic reaction for coumarins, paeoniflorin and iridoids. This investigation provided important structural information on the metabolism of HLXLD and provided scientific evidence to obtain a more comprehensive metabolic profile. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Isolation and purification of monosialotetrahexosylgangliosides from pig brain by extraction and liquid chromatography 下载免费PDF全文
Monosialotetrahexosylganglioside (GM1), one of glycosphingolipids containing sialic acid, plays particularly important role in fighting against paralysis, dementia and other diseases caused by brain and nerve damage. In this work, a simple and highly efficient method with high yield was developed for isolation and purification of GM1 from pig brain. The method consisted of an extraction by chloroform–methanol–water and a two‐step chromatographic separation by DEAE–Sepharose Fast Flow anion‐exchange medium and Sephacryl S‐100 HR size‐exclusion medium. The purified GM1 was proved to be homogeneous and had a purity of >98.0% by high‐performance anion‐exchange and size‐exclusion chromatography. The molecular weight was 30.0 kDa by high‐performance size‐exclusion chromatography and 1546.9 Da by electrospray ionization mass spectrometry. The chromogenic reaction by resorcinol–hydrochloric acid solution indicated that the purified GM1 showed a specific chromogenic reaction of sialic acid. Through this isolation and purification program, ~1.0 mg of pure GM1 could be captured from 500 g wet pig brain tissue and the yield of GM1 was around 0.022%, which was higher than the yields by other methods. The method may provide an alternative for isolation and purification of GM1 in other biological tissues. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Li+/Mg2+ Hybrid‐Ion Batteries with Long Cycle Life and High Rate Capability Employing MoS2 Nano Flowers as the Cathode Material 下载免费PDF全文
Yanming Ju Yuan Meng Prof. Yingjin Wei Xiaofei Bian Qiang Pang Dr. Yu Gao Prof. Fei Du Prof. Bingbing Liu Prof. Gang Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):18073-18079
The demand for large‐scale and safe energy storage is increasing rapidly due to the strong push for smartphones and electric vehicles. As a result, Li+/Mg2+ hybrid‐ion batteries (LMIBs) combining a dendrite‐free deposition of Mg anode and Li+ intercalation cathode have attracted considerable attention. Here, a LMIB with hydrothermal‐prepared MoS2 nano flowers as cathode material was prepared. The battery showed remarkable electrochemical properties with a large discharge capacity (243 mAh g?1 at the 0.1 C rate), excellent rate capability (108 mAh g?1 at the 5 C rate), and long cycle life (87.2 % capacity retention after 2300 cycles). Electrochemical analysis showed that the reactions occurring in the battery cell involved Mg stripping/plating at the anode side and Li+ intercalation at the cathode side with a small contribution from Mg2+ adsorption. The excellent electrochemical performance and extremely safe cell system show promise for its use in practical applications. 相似文献
997.
Study on the interaction of plasma protein binding rate between edaravone and taurine in human plasma based on HPLC analysis coupled with ultrafiltration technique 下载免费PDF全文
Dao‐quan Tang Yin‐jie Li Zheng Li Ting‐ting Bian Kai Chen Xiao‐xiao Zheng Yan‐yan Yu Shui‐shi Jiang 《Biomedical chromatography : BMC》2015,29(8):1137-1145
In this work, two high‐performance liquid chromatography (HPLC) assays were developed and validated for the independent determination of edaravone and taurine using 3‐methyl‐1‐p‐tolyl‐5‐pyrazolone and L ‐glutamine as internal standards. In in vitro experiments, human plasma was separately spiked with a mixture of edaravone and taurine, edaravone or taurine alone. Plasma was precipitated with acetonitrile containing 0.1% formic acid. Ultrafiltration was employed to obtain the unbound ingredients of the two drugs. The factors that might influence the ultrafiltration effiency were elaborately optimized. Plasma supernatant and ultrafiltrate containing taurine were derivated with o‐phthalaldehyde and ethanethiol in the presence of 40 mmol/L sodium borate buffer (pH 10.2) at room temperature within 1 min. Chromatographic separations were achieved on an InertSustain C18 column (250 × 4.6 mm, 5 µm). Isocratic 50 mmol/L ammonium acetate–acetonitrile and gradient 50 mmol/L sodium acetate (pH 5.3)–methanol were respectively selected as the mobile phase for the determination of edaravone and taurine. All of the validation data including linearity, extraction recovery, precision, accuracy and stability conformed to the requirements. Results showed that there were no significant alterations in the plasma protein binding rate of taurine and edaravone, implying that the proposed combination therapy was pharmacologically feasible. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Comparative metabolism of four limonoids in human liver microsomes using ultra‐high‐performance liquid chromatography coupled with high‐resolution LTQ‐Orbitrap mass spectrometry 下载免费PDF全文
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