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41.
Neil A. Koorbanally Neil R. Crouch Avinash Harilal Bavani Pillay Dulcie A. Mulholland 《Biochemical Systematics and Ecology》2006
We report on the first phytochemical investigation of a member of the African genus Resnova (Hyacinthoideae: Hyacinthaceae). From the dichloromethane extract of the bulbs of both Resnova humifusa and Eucomis montana (Hyacinthoideae: Hyacinthaceae) a novel 3-benzyl-4-chromanone homoisoflavonoid, 5,6-dimethoxy-7-hydroxy-3-(4′-hydroxybenzyl)-4-chromanone, was isolated. A further 11 known homoisoflavonoids were also identified, the 12 in total presenting a clear biosynthetic sequence. Eight of the 12 compounds found were common to both species. 相似文献
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Nucleotide sequences of three soybean chloroplast tRNAsLeu and re-examination of bean chloroplast tRNA2Leu sequence. 总被引:6,自引:3,他引:3 下载免费PDF全文
The nucleotide sequences of soybean chloroplast tRNAsLeu were determined using post-labeling techniques. Comparison of the primary structures of soybean chloroplast tRNAsLeu with their bean, maize and spinach counterparts only show few base differences. Contrary to previously published results (1) a re-examination of bean tRNALeu sequence shows that this tRNA resembles soybean and maize tRNA2Leu in structure. 相似文献
44.
Mohammed A. Khedr Melendhran Pillay Sandeep Chandrashekharappa Deepak Chopra Bandar E. Aldhubiab Mahesh Attimarad 《Journal of biomolecular structure & dynamics》2018,36(8):2163-2178
A series of trisubstituted indolizine analogues has been designed as a result of a fragment-based approach to target the inhibition of mycobacterial enoyl-acyl carrier protein reductase. Anti-tuberculosis (TB) screening of the characterized compounds by a resazurin microplate assay method revealed that ethyl group at second position of indolizine nucleus exhibited activity against susceptible and multidrug-resistant strains of Mycobacterium tuberculosis at concentration of 5.5 and 11.3 μg/mL, respectively. A molecular docking study was also conducted to evaluate the stability of the active compounds, and compound with ethyl substitution at second position of indolizine nucleus showed the highest free binding energy of ΔG ?24.11 (kcal/mol), a low clash score of 3.04, and high lipo score of ?13.33. Indolizine analog with ethyl substitution at second position demonstrated Molecular Mechanics/Generalized Born Surface Area (?23.85 kcal/mol). Two molecular dynamics studies were computed (100 ps and 50 ns) to calculate the relationship between the potential and kinetic energies of the active anti-TB compound with time and temperature. The discovery of this lead may have a positive impact on anti-TB drug discovery. 相似文献
45.
The seasonal fluctuations in the incidence of planktonic organisms and the larval forms of certain crustaceans such as crabs, barnacles and post larvae of prawns in the plankton of the south-west coast of India have been followed for a period of three years from 1963. South-west monsoon period is the least productive period for zooplankton in this area. Brachyuran zoeae, post larvae of prawns and barnacle nauplii occur in the plankton throughout the year with distinct peaks for different groups. The zoeae ofUca annulipes occur in the plankton from September to May with a peak during November–December. The zoeae ofPortunus pelagicus are present in the plankton from September to June and their abundance is in February–March. The post larvae ofMetapenaeus affinis are found in the inshore plankton from November to June with the peak in March. The nauplii ofBalanus amphitrite communis occur in the plankton in all the months of the year, the peak incidence has been during November January. The zoeae ofU. annulipes are found to tolerate better the medium saline conditions. Of the ecological factors, salinity of the ambient water and the availability of planktonic food for the larvae seem to influence the seasonal fluctuations of these crustacean larvae in this locality. 相似文献
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The purpose of this study was to develop a drug-loaded nanosystem that has the ability to achieve flexible yet rate-controlled
release of model drug isoniazid (INH) employing either an aqueous or emulsion-based salting-out approach. Formulation conditions
were aimed at reducing the polymeric size with subsequent rate-modulated INH release patterns from the polymeric nanosystem.
The emulsion-based salted-out nanosystems had particle sizes ranging from 77–414 nm and a zeta potential of −24 mV. The dispersant
dielectric constant was set at 78.5 and a conductivity of 3.99 mS/cm achieved. The reduced nanosystem size of the aqueous-based
approach has demonstrated an intrinsically enhanced exposure of methacrylic acid-ethyl acrylate to zinc sulphate which was
employed as a crosslinking reagent. This resulted in robustly interconnected polymeric supports in which INH was efficiently
embedded and subsequently released. The multi-layer perceptron data obtained showed that the aqueous and emulsion-based salting
out approaches had Power (law) (MSE = 0.020) and Linear (MSE = 0.038) relationships, respectively. Drug release from the nanosystems
occurred in two phases with an initial burst-release in aqueous-based nanosystems (30–100%) and significantly lower bursts
observed in emulsion-based nanosystems (20–65%) within the first 2 h. This was followed by a gradual exponential release phase
over the remaining 12 h. The nanosystems developed demonstrated the ability to control the release of INH depending on the
formulation approach adopted. 相似文献
49.
Amplified fragment length polymorphisms reveal genetic differentiation among strains of Xanthomonas albilineans 总被引:1,自引:0,他引:1
Xanthomonas albilineans, the causative agent of leaf scald disease (LSD), colonizes the vascular system of sugarcane (Saccharum spp. hybrids). In this study X. albilineans strains from 28 countries were differentiated by using two methods of amplified fragment length polymorphism (AFLP). In the manual procedure, AFLP reactions were performed on 57 X. albilineans strains and after selective amplification using radiolabelled primers, the resulting products were separated using polyacrylamide gel electrophoresis. The autoradiographs were analyzed using GelCompar version 4.1 software (Applied Maths) to construct dendograms from similarity matrices. Fluorescent AFLP (FAFLP) was also employed on 52 X. albilineans strains using three fluorescently labelled primer combinations (automated AFLP). The FAFLP data was converted to a binary format using the Genemapper Software 3.7 (Applied Biosystems). Thereafter, dendograms were generated using the NTSYSpc. Software (USA). Distinct AFLP profiles were produced for the majority of the strains and were found to be useful in differentiating X. albilineans strains from various geographical locations. Fingerprints unique to each strain were reproducibly obtained and may be used to create a database for use in the identification of the various X. albilineans strains. It can be also concluded from the results obtained that the FAFLP has considerable technical advantages compared with the manual AFLP and also that the FAFLP is more sensitive than AFLP using radiolabelled primers in differentiating X. albilineans. 相似文献