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71.
Green chillies(Capsicum annum L.) and tamarind (Tamarindus indica) contain appreciable amount of L-asparaginase. The enzyme was purified 400-fold from green chillies, by successive precipitations
with ammonium sulphate and sodium sulphate, Sephadex-gel filtration and affinity chromatography and the purified enzyme was
homogenous on gel electrophoresis. The enzyme exists in two forms, only one having antitumour activity.
The purified enzyme has a molecular weight of 120,000 ±500. The N-terminal and the C-terminal amino acids are alanine and
phenylalanine, respectively. The enzyme has a sharp optimum pH of 8.5 and a temperature optimum of 37‡C. It is stable upto
40‡C. The energy of activation is 3 kilo calories. The Km value for the enzyme is 3.3. mm. The enzyme has little action on D-asparagine, which is a strong inhibitor. The enzyme has
inseparable glutaminase ctivity and is thus an asparaginase—glutaminase. In addition, it possesses urease activity. 相似文献
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74.
Guobin He Debanjan Dhar Hayato Nakagawa Joan Font-Burgada Hisanobu Ogata Yuhong Jiang Shabnam Shalapour Ekihiro Seki Shawn E. Yost Kristen Jepsen Kelly A. Frazer Olivier Harismendy Maria Hatziapostolou Dimitrios Iliopoulos Atsushi Suetsugu Robert M. Hoffman Ryosuke Tateishi Kazuhiko Koike Michael Karin 《Cell》2013
75.
Iqra Ishaaq Muhammad Umer Farooq Syeda Anjum Tahira Rizwana Maqbool Celaleddin Barutçular Muhammad Yasir Saira Bano Zaid Ulhassan Ghassan Zahid Muhammad Ahsan Asghar Sajad Hussain Kocsy Gabor Ulkar Ibrahimova Jianqing Zhu Anshu Rastogi 《Phyton》2022,91(12):2733-2758
Drought is the major detrimental environmental factor for wheat (Triticum aestivum L.) production. The exploration of genetic patterns underlying drought tolerance is of great significance. Here we report the gene actions controlling the phenological traits using the line × tester model studying 27 crosses and 12 parents under normal irrigation and drought conditions. The results interpreted via multiple analysis (mean performance, correlations, principal component, genetic analysis, heterotic and heterobeltiotic potential) disclosed highly significant differences among germplasm. The phenological waxiness traits (glume, boom, and sheath) were strongly interlinked. Flag leaf area exhibits a positive association with peduncle and spike length under drought. The growing degree days (heat-units) greatly influence spikelets and grains per spike, however, the grain yield/plant was significantly reduced (17.44 g to 13.25 g) under drought. The principal components based on eigenvalue indicated significant PCs (first-seven) accounted for 79.9% and 73.9% of total variability under normal irrigation and drought, respectively. The investigated yield traits showed complex genetic behaviour. The genetic advance confronted a moderate to high heritability for spikelets/spike and grain yield/plant. The traits conditioned by dominant genetic effects in normal irrigation were inversely controlled by additive genetic effects under drought and vice versa. The magnitude of dominance effects for phenological and yield traits, i.e., leaf twist, auricle hairiness, grain yield/plant, spikelets, and grains/spike suggests that selection by the pedigree method is appropriate for improving these traits under normal irrigation conditions and could serve as an indirect selection index for improving yield-oriented traits in wheat populations for drought tolerance. However, the phenotypic selection could be more than effective for traits conditioned by additive genetic effects under drought. We suggest five significant cross combinations based on heterotic and heterobeltiotic potential of wheat genotypes for improved yield and enhanced biological production of wheat in advanced generations under drought. 相似文献
76.
Siddiqui S Dai Z Stavis CJ Zeng H Moldovan N Hamers RJ Carlisle JA Arumugam PU 《Biosensors & bioelectronics》2012,35(1):284-290
It is well recognized that label-free biosensors are the only class of sensors that can rapidly detect antigens in real-time and provide remote environmental monitoring and point-of-care diagnosis that is low-cost, specific, and sensitive. Electrical impedance spectroscopy (EIS) based label-free biosensors have been used to detect a wide variety of antigens including bacteria, viruses, DNA, and proteins due to the simplicity of their detection technique. However, their commercial development has been hindered due to difficulty in interpreting the change in impedance upon antigen binding and poor signal reproducibility as a result of surface fouling and non-specific binding. In this study, we develop a circuit model to adequately describe the physical changes at bio functionalized surface and provide an understanding of the detection mechanism based on electron exchange between electrolyte and surface through pores surrounding antibody-antigen. The model was successfully applied to extract quantitative information about the bio surface at different stages of surface functionalization. Further, we demonstrate boron-doped ultrananocrystalline diamond (UNCD) microelectrode array (3 × 3 format, 200 μm diameter) improves signal reproducibility significantly and increases sensitivity by four orders of magnitude. This study marks the first demonstration of UNCD array based biosensor that can reliably detect a model Escherichia coli K12 bacterium using EIS, positioning this technology for rapid adoption in point-of-use applications. 相似文献
77.
Rekha Sapru Dhar Suphla Bajpai Gupta Parvinder Pal Singh Sumeer Razdan Wajid Waheed Bhat Satiander Rana Surrinder Kumar Lattoo Shabnam Khan 《Journal of plant biochemistry and biotechnology.》2012,21(1):77-87
To have better understanding of the processes that occur in Withania somnifera L. Dunal, proteome analyses were initiated on two tissues (seeds & leaves) of this plant. Protein extracts were separated by two-dimensional gel electrophoresis (2-DE) across a broad 3.0?C10.0 immobilized pH gradient (IPG) strip that yielded 434 protein spots. A total of 167 individual spots (82 from seeds and 85 from leaves) were excised from the gel and were characterized by peptide mass fingerprinting. From these analyses, 70 individual proteins from seeds and 74 from leaves were identified by protein sequence database interrogation and were catalogued accordingly to different protein functions. A comparative analysis of the two tissues indicated that some enzymes/proteins involved in housekeeping pathways were common to both, whereas some were exclusively tissue specific with specialized metabolic complement. The knowledge gained by this study towards the tissue specific protein expression in W. somnifera would form the basis for our future endeavor of characterization of proteins to understand the physiology and the associated complex metabolic network during its ontogenetic development. 相似文献
78.
Enrico Gobbato John F. Marsh Tatiana Vernié Ertao Wang Fabienne Maillet Jiyoung Kim J. Benjamin Miller Jongho Sun S. Asma Bano Pascal Ratet Kirankumar S. Mysore Jean Dénarié Michael Schultze Giles E.D. Oldroyd 《Current biology : CB》2012,22(23):2236-2241
Download : Download video (88MB) 相似文献
79.
I.G. Rathish Kalim Javed Shamim Ahmad Sameena Bano M.S. Alam K.K. Pillai Surender Singh Vivek Bagchi 《Bioorganic & medicinal chemistry letters》2009,19(1):255-258
Nineteen new 2-pyrazoline bearing benzenesulfonamide derivatives were synthesized by condensing chalcones with 4-hydrazinonbenzenesulfonamide hydrochloride. Their chemical structures were proved by means of IR, 1H NMR, 13C NMR, mass spectroscopic and elemental analyses data. These compounds were tested at dose of 20 mg/kg for their anti-inflammatory activity in carrageenan-induced rat paw edema model and volume of paw edema was measured at 0, 3 and 5 h. Two compounds 3k and 3l were found to be more active than celecoxib throughout the study (at 3 and 5 h). While two other compounds 3m and 3n showed more potent activity than celecoxib at 5 h. They are devoid of ulcerogenic potential when administered orally at a dose of 60 mg/kg. Compounds (3k–m) showed COX-1 and COX-2 inhibitory activity at 0.05 μM. 相似文献
80.