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51.
In the search of new trypsin inhibitors caffeic acid (1), cinnamic acid (2), gallic acid (3) and eugenol (4) from Cinnamomum zeylanicum, ferulic acid (5) from Impatiens bicolor, vanillin (6) from Melia azedarach and catechol (7) from Allium cepa were isolated through bioassay guided fractionation of the plant extracts. IC (50) values of the compounds 1, 2 and 5 were found to be 0.35?±?0.02?mM, 0.96?±?0.05?mM and 1.22?±?0.06?mM, respectively. Lineweaver-Burk and Dixon plots and their secondary replots showed that 1 was non-competitive inhibitor of this enzyme with K(i) value 0.102?±?0.006?mM.  相似文献   
52.
The leaves of Cinnamomum iners (Reinw. ex Blume-Lauraceae) have been refluxed successively with chloroform and alcohol to get chloroform extract and alcoholic extract. Both the extracts have been assayed for cytotoxicity against human colorectal tumour cells. The chloroform extract exhibited significant cytotoxicity with IC(50) 31?μg mL(-1) (p??200?μg mL(-1). The chloroform extract has been further proceeded for chemical analysis by GC-TOFMS and 178 components were identified including acids, amines, amides, aldehydes, alcohols, esters, benzene derivatives, bicyclic compounds, terpenes, hydrocarbons, naphthalene derivatives, furan derivatives, azulenes, etc. Nine components representing 51.73% of the total chloroform extract were detected as major components. Caryophyllene (14.41%) and Eicosanoic acid ethyl ester (12.17%) are the most prominent components of the chloroform extract. β-Caryophyllene (14.41%) as most abundant compound supports potent cytotoxicity as shown by chloroform extract.  相似文献   
53.
The synthetic standards for cysteine and valine adducts of sulphur mustard have been synthesized using 2-(2-chloroethylthio) ethanol (half-mustard). These adducts have been recognized as biomarkers for exposure to sulphur mustard. The adducts have been fully characterized using 1 H and 13 C NMR spectroscopy and mass spectrometric techniques.  相似文献   
54.
Abstract

A series of structurally related unsymmetrically substituted methylphosphonate diesters have been synthesised and subjected to electron impact (El) mass spectral studies. These studies though aimed at total identification of the compounds, resulted in certain interesting observations and hence are being reported. In order to confirm the observations under electron impact and to support the mechanism of fragmentation we have also performed MSNS experiments in both daughter ion and parent ion modes.  相似文献   
55.
Bacterial infection poses life-threatening challenge to humanity and stimulates to the researchers for developing better diagnostic and therapeutic agents complying with existing theranostic techniques. Nuclear medicine technique helps to visualize hard-to-diagnose deep-seated bacterial infections using radionuclide-labeled tracer agents. Metronidazole is an antiprotozoal antibiotic that serves as a preeminent anaerobic chemotherapeutic agent. The aim of this study was to develop technetium-99m-labeled metronidazole radiotracer for the detection of deep-seated bacterial infections. Radiosynthesis of 99mTc-metronidazole was carried by reacting reduced technetium-99m and metronidazole at neutral pH for 30 min. The stannous chloride dihydrate was used as the reducing agent. At optimum radiolabeling conditions, ~ 94% radiochemical was obtained. Quality control analysis was carried out with a chromatographic paper and instant thin-layer chromatographic analysis. The biodistribution study of radiochemical was performed using Escherichia coli bacterial infection-induced rat model. The scintigraphic study was performed using E. coli bacterial infection-induced rabbit model. The results showed promising accumulation at the site of infection and its rapid clearance from the body. The tracer showed target-to-non-target ratio 5.57 ± 0.04 at 1 h post-injection. The results showed that 99mTc-MNZ has promising potential to accumulate at E. coli bacterial infection that can be used for E. coli infection imaging.  相似文献   
56.

Abstract  

Cyclohexyl N-phenylcarbamate, C13H17NO2 (I), which is a useful target for biotransformations by fungi, has been synthesized and the structure has been solved by X-ray diffraction. The crystals are triclinic, space group P [`1] bar{1} , with a = 5.2581 (2) ?, b = 9.5080 (3) ?, c = 12.6165 (4) ?, α = 70.544 (2)°, β = 89.075 (2)°, γ = 80.447 (2)°, M r = 219.28, V = 585.96 (3) ?3, Z = 2 and R = 0.065. In the title compound the phenyl ring makes a dihedral angle of 30.68(7)° with the carbamate group The molecules are linked into infinite chains via N–H···O hydrogen bonds along the a axis. These hydrogen-bonded chains are further linked by weaker C–H···π interactions. Quantum-mechanical ab initio calculations for the free molecule reproduce well the observed bond lengths and valency angles but show that the crystal packing might be responsible for the rotation of the phenyl ring out of the carbamate plane in the solid state conformation.  相似文献   
57.
58.
The bark and wood of Sonneratia caseolaris (L.) Engl. have been analyzed for chemical profile by GC–TOFMS. Overall thirty-two compounds from bark and twenty-eight compounds from wood have been detected. Sixteen constituents have been found to be common in both the extracts. GC–TOFMS chemical profile may be a significant finger print chemotaxonomic marker as an identity of this plant.  相似文献   
59.
This study was designed to check the potential of secondary metabolites of the selected plants; Citrullus colocynthis, Solanum nigrum, Solanum surattense, Calotropis procera, Agave americana, and Anagallis arvensis for antioxidant, antibacterial, antifungal, and antidiabetic agents. Plant material was soaked in ethanol/methanol to get the crude extract, which was further partitioned via solvent extraction technique. GCMS and FTIR analytical techniques were applied to check the compounds responsible for causing antioxidant, antimicrobial, and antidiabetic activities. It was concluded that about 80% of studied extracts/fractions were active against α-amylase, ranging from 43 to 96%. The highest activity (96.63%) was exhibited by butanol fractions of A. arvensis while the least response (43.65%) was shown by the aqueous fraction of C. colocynthis and the methanol fraction of fruit of S. surattense. The highest antioxidant activity was shown by the ethyl acetate fraction of Anagallis arvensis (78.1%), while aqueous as well as n-hexane fractions are the least active throughout the assay. Results showed that all tested plants can be an excellent source of natural products with potential antimicrobial, antioxidant, and antidiabetic potential. The biological response of these species is depicted as a good therapeutic agent, and, in the future, it can be encapsulated for drug discovery.  相似文献   
60.
A new triterpene named as alysinol 3alpha, 22beta-dihydroxyolean-12-ene [structure: see text] along with known compounds usnic acid, methyl 2,4-dihydroxy-3,6-dimethyl benzoate, 3-hydroxy benzoic acid, stigmasterol, poriferasterol and ursolic acid have been isolated from Alysicarpus monolifer. The structure of [structure: see text] has been established through spectroscopic techniques.  相似文献   
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