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151.
Small molecular biothiols, cysteine (Cys), homocysteine (Hcy) and glutathione (GSH), play important roles in organisms, and their concentration levels are indicative of some human diseases. Herein we report an organic dye-conjugated β-diketonate-Eu3+ complex, [Eu(NBD-keto)3(DPBT)] (NBD-keto: 7-nitro-2,1,3-benzoxadiazole (NBD)-conjugated to 1,1,1,2,2-pentafluoro-5-phenyl-3,5-pentanedionate through a “O” ether bond; DPBT: 2-(N,N-diethylanilin-4-yl)-4,6-bis(3,5-dimethylpyrazol-1-yl)-1,3,5-triazine), which acts as a unique luminescent probe for detecting and discriminating biothiols. [Eu(NBD-keto)3(DPBT)] itself is not luminescent due to intramolecular interactions between NBD and β-diketonate-Eu3+ moieties. Upon reaction with biothiols, the β-diketonate-Eu3+ complex [Eu(keto)3(DPBT)] is generated, which emits long-lived red emission at 610 nm. Meanwhile, three biothiol-substituted NBD derivatives that exhibit different luminescence behaviors, green emissive (short-lived) NBD-NR (R=Cys or Hcy) at 540 nm and non-luminescent NBD-SR (R=GSH), are also generated. These luminescence response behaviors allow time-gated and steady-state luminescence modes to be combined for detecting total biothiols and discriminating GSH and Cys/Hcy. Using this probe, the quantitative detection and discrimination of GSH and Cys/Hcy in lysis solutions of HeLa cells were realized, which revealed the potential of the probe for biomedical applications. 相似文献
152.
Yixuan Tang Shihui Huang Xingxing Chen Junzhang Huang Qianwen Lin Lei Huang Shuping Wang Qihua Zhu Yungen Xu Yi Zou 《Molecules (Basel, Switzerland)》2022,27(19)
Protein arginine methyltransferases 5 (PRMT5) is a clinically promising epigenetic target that is upregulated in a variety of tumors. Currently, there are several PRMT5 inhibitors under preclinical or clinical development, however the established clinical inhibitors show favorable toxicity. Thus, it remains an unmet need to discover novel and structurally diverse PRMT5 inhibitors with characterized therapeutic utility. Herein, a series of tetrahydroisoquinoline (THIQ) derivatives were designed and synthesized as PRMT5 inhibitors using GSK-3326595 as the lead compound. Among them, compound 20 (IC50: 4.2 nM) exhibits more potent PRMT5 inhibitory activity than GSK-3326595 (IC50: 9.2 nM). In addition, compound 20 shows high anti-proliferative effects on MV-4-11 and MDA-MB-468 tumor cells and low cytotoxicity on AML-12 hepatocytes. Furthermore, compound 20 possesses acceptable pharmacokinetic profiles and displays considerable in vivo antitumor efficacy in a MV-4-11 xenograft model. Taken together, compound 20 is an antitumor compound worthy of further study. 相似文献
153.
154.
We report a method of coupled CE-LIF detection with flow cytometry for high-throughput determination and quantitation of fluorophores in single intact K562/S (KS) cells. The membrane properties of KS cell including fluophore transport rate and apparent permeability coefficient were further quantitatively characterized. The method has advantages for accurate quantitation and unique capacity of high-throughput analysis. The strategy will be useful for the quantitation of fluorophores in the intact cells, such as measurement of multidrug resistance, quantitation of specific protein expression, and quantitative characterization of protein and enzyme functions. 相似文献
155.
Jianjun Zou Dingwei Wu Dawei Xiao Dan Qi Li Liu Li Ding Guangji Wang 《Chromatographia》2009,69(5-6):453-458
A sensitive and specific liquid chromatography–electrospray ionization–tandem mass spectrometry method has been developed and validated for the quantification of huperzine A in human plasma. After the addition of trimetazidine, the internal standard (IS) and sodium hydroxide, plasma samples were extracted using 5 mL ethyl acetate. The compounds were separated on an Agilent Zorbax SB C18 column (100 mm × 2.1 mm ID, dp 3.5 μm) using an elution system of 10 mM ammonium acetate solution–methanol–formic acid (18:82:0.1, v/v) as the mobile phase. The quantification of target compounds was obtained by using multiple reaction monitoring (MRM) transitions: m/z 243.1, 210.1 and 267.2, 166.0 were measured in positive mode for huperzine A and IS. Linearity was established for the range of concentrations 0.01–4.0 ng mL?1 with a coefficient of correlation (r) of 0.9991. The lower limit of quantification (LLOQ) was identifiable and reproducible at 0.01 ng mL?1. The method has been successfully applied to study the pharmacokinetics of huperzine A in healthy male Chinese volunteers. 相似文献
156.
The Role of Processing Solvent on Morphology Optimization for Slot-Die Printed Organic Photovoltaics
Wang Lei Zhan Jun-Zhe Zhong Wen-Kai Zhu Lei Zhou Guan-Qing Hao Tian-Yu Zou Ye-Cheng Wang Zhen-Hua Wei Gang Zhang Yong-Ming Liu Feng 《高分子科学》2023,41(6):842-850
Chinese Journal of Polymer Science - The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics (OPVs). The choice of processing solvent... 相似文献
157.
158.
Five new eclipsed two-dimensional (2D) coordination polymers, [[Cd(2)(TPT)(2)L(2)](GM(1))(3/2)(H(2)O)](infinity) (1) (TPT = terephthalate, L = 3-(2-pyridyl)pyrazole, GM(1) = terephthalic acid), [[Cd(TPT)L](GM(2))(H(2)O)(2)]( infinity) (2) (GM(2) = L = 3-(2-pyridyl)pyrazole), [[Cd(TPT)L](GM(3))(1/2)(H(2)O)](infinity) (3) (GM(3) = mesitylene), [[Cd(4)(TPT)(4)L(4)](GM(4))(7/2)](infinity) (4) (GM(4) = tetramethylbenzene), and [[Cd(TPT)L](GM(5))(1/2)](infinity) (5) (GM(5) = naphthalene), have been synthesized and characterized by X-ray diffraction. All the five complexes take the similar eclipsed 2D open-channel framework with different guest molecules included in the cavities of their channels. TGA analysis indicates that the eclipsed open-channel frameworks are thermally stable up to 300 degrees C. The porous property of the 2D framework of 5 was also investigated by the XRPD technique, which indicated that the guest molecules included in the open-channel frameworks are removable and the framework is maintained after the removal of the guest molecules. Moreover, complexes 1-5 also display strong blue emission in the solid state. 相似文献
159.
Zhou J An L Liu X Zou H Hu F Liu C 《Chemical communications (Cambridge, England)》2012,48(19):2537-2539
One novel 1-D europium thioindate-thioantimonate {[Eu(tepa)](2)[μ(2)-SbS(3)](μ(2)-H(2)O)}[Eu(tepa)In(4)S(9)]·0.25tepa (1, tepa = tetraethylenepentamine) has been solvothermally synthesized. 1 represents the first example of the coordination of a soft Lewis basic 1-D polymeric [In(4)S(9)(6-)](n) ligand to a hard Lewis acidic Eu(3+) ion. The wide-band-gap semiconductor and photoluminescence properties of 1 have been investigated. 相似文献
160.
In the present study the capacity of Radix Paeoniae Rubra aqueous extract (RPRAE) as an antioxidant to protect against carbon tetrachloride (CCl(4))-induced oxidative stress and hepatotoxicity in Wistar rats was investigated. Six groups of rats were used. Radix Paeoniae Rubra aqueous extract (100 or 200 or 300 mg/kg of bw) or bifendate (100 mg/kg of bw) were given daily by gavage to the animals on 28 consecutive days to elucidate the protective effects against CCl(4)-induced hepatotoxicity. The 20% CCl(4)/olive oil was gavage of gastric tube twice a week (on the third and seventh days of each week). The animals of normal control group were given only vehicle. The animals of CCl(4)-treated group were administered with CCl(4) twice a week (on the third and seventh days of each week) and with vehicle on rest of the days. The test materials were found effective as hepatoprotective agents, as evidenced by plasma and liver biochemical parameters. Therefore, the results of this study show that Radix Paeoniae Rubra aqueous extract can protect the liver against CCl(4)-induced oxidative damage in rats, and the hepatoprotective effects might be correlated with its antioxidant and free radical scavenger effects. 相似文献