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101.
Summary The relative efficiency of seven extractants for estimating available Cu in sierozem soils of Haryana was studied. Bulk samples
of 15 soils ranging in neutral normal amm. acetate extractable Cu from 0.12 to 0.20 ppm were subjected to screen-house study.
The quantities of Cu extracted with neutral normal amm. acetate, Morgan’s reagent (pH 4.8)N ammonium acetate (pH 4.8), 0.1N HCl, 0.02M EDTA, critrate-EDTA and DTPA from soils were examined for their correlation with responses of maize in terms of Bray’s percentage
yield and percentage Cu uptake. The highest coefficient of correlation was obtained between Cu extractable with neutral 1N NH4OAc and Bray’s per cent yield and per cent Cu uptake. All other methods showed lower values of correlation. The critical level
of available Cu estimated with use of neutral normal NH4OAc was 0.16 ppm. Below this value, responses to applied Cu can be expected. 相似文献
102.
103.
104.
Abstract Stable reagents were made from nucleoside-phospho-rochloridites and polymeric sec. amines. Treatment of these with tetrazole/CH3CN and transfer of the resulting solution to immobilized oligonucleotide gave 95% chain elongation. 相似文献
105.
106.
Praveen Chandra Verma Laiq ur Rahman Arvind Singh Negi Dharm Chand Jain S. P. S. Khanuja Suchitra Banerjee 《Plant biotechnology reports》2007,1(3):169-174
A protocol for induction and establishment of Agrobacterium rhizogenes-mediated hairy root cultures of Picrorhiza kurroa was developed through optimization of the explant type and the most suitable bacterial strain. The infection of leaf explants
with the LBA9402 strain resulted in the emergence of hairy roots at 66.7% relative transformation frequency. Nine independent,
opine and TL-positive hairy root clones were studied for their growth and specific glycoside (i.e., kutkoside and picroside I) productivities
at different growth phases. Biosynthetic potentials for the commercially desirable active constituents have been expressed
by all the tested hairy root clones, although distinct inter-clonal variations could be noted in terms of their quantity.
The yield potentials of the 14-P clone, both in terms of biomass as well as individual glycoside contents (i.e., kutkoside
and picroside I), superseded that of all other hairy root clones along with the non-transformed, in vitro-grown control roots
of P. kurroa. The present communication reports the first successful establishment, maintenance, growth and selection of superior hairy
root clone of Picrorhiza kurroa with desired phyto-molecule production potential, which can serve as an effective substitute to its roots and thereby prevent
the indiscriminate up-rooting and exploitation of this commercially important, endangered medicinal plant species.
CIMAP Publication No.: 2007-28J 相似文献
107.
Kamaluddin Rishi Muni Singh Malik Zainul Abdin Mather Ali Khan Tanweer Alam Salim Khan Lal Chand Prasad Arun Kumar Joshi 《Journal of Plant Biology》2007,50(4):504-507
To understand the genetic control of grain filling duration (GFD), i.e., the number of days from anthesis to physiological
maturity, we studied the F1, F2, BC1 and BC2 generations of six spring wheat crosses from nine varieties/genotypes. Generation mean analysis for gene effects indicated
that one or more types of epistasis were significant in all crosses. In each pairing, the F1 and F2 means were either intermediate or closer to the mean of the parent having the longer GFD. Our narrow-sense heritability estimate
was reasonably high, at 47.67 (based on diallel analysis). This demonstrated that progress could be made from the selection
in these crosses for either long or short GFD. The two early varieties that had identical maturity durations differed in their
GFD values, indicating that maturity dates are not good criteria when choosing parents for modifying GFD. To utilize favorable
additive × additive effects during this selection, we suggest that a single seed descent (SSD) or bulk popula-tion approach
be adopted. In comparison, dominance effects would prove quite useful in hybrid wheat breeding programs. 相似文献
108.
Nikhilesh S. Chand Anne E. Clatworthy Deborah T. Hung 《Journal of bacteriology》2012,194(23):6537-6547
Pseudomonas aeruginosa is an opportunistic pathogen that is capable of causing both acute and chronic infections. P. aeruginosa virulence is subject to sophisticated regulatory control by two-component systems that enable it to sense and respond to environmental stimuli. We recently reported that the two-component sensor KinB regulates virulence in acute P. aeruginosa infection. Furthermore, it regulates acute-virulence-associated phenotypes such as pyocyanin production, elastase production, and motility in a manner independent of its kinase activity. Here we show that KinB regulates virulence through the global sigma factor AlgU, which plays a key role in repressing P. aeruginosa acute-virulence factors, and through its cognate response regulator AlgB. However, we show that rather than phosphorylating AlgB, KinB''s primary role in the regulation of virulence is to act as a phosphatase to dephosphorylate AlgB and alleviate phosphorylated AlgB''s repression of acute virulence. 相似文献
109.
Lazarus KA Wijayakumara D Chand AL Simpson ER Clyne CD 《The Journal of steroid biochemistry and molecular biology》2012,130(3-5):138-146
Liver Receptor Homolog-1 (LRH-1; NR5A2) belongs to the orphan nuclear receptor superfamily, and plays vital roles in early development, cholesterol homeostasis, steroidogenesis and certain diseases, including cancer. It is expressed in embryonic stem cells, adult liver, intestine, pancreas and ovary. It binds to DNA as a monomer and is regulated by various ligand-dependent and -independent mechanisms. Recent work identified synthetic ligands for LRH-1; such compounds may yield useful therapeutics for a range of pathologic conditions associated with aberrant expression and activity of LRH-1. 相似文献
110.
Verbanac D Jain SC Jain N Chand M Cipčić Paljetak H Matijašić M Perić M Stepanić V Saso L 《Bioorganic & medicinal chemistry》2012,20(10):3180-3185
Xanthones and their thio-derivatives are a class of pleiotropic compounds with various reported pharmacological and biological activities. Although these activities are mainly determined in laboratory conditions, the class itself has a great potential to be utilized as promising chemical scaffold for the synthesis of new drug candidates. One of the main obstacles in utilization of these compounds was related to the difficulties in their chemical synthesis. Most of the known methods require two steps, and are limited to specific reagents not applicable to a large number of starting materials. In this paper a new and improved method for chemical synthesis of xanthones is presented. By applying a new procedure, we have successfully obtained these compounds with the desired regioselectivity in a shorter reaction time (50s) and with better yield (>80%). Finally, the preliminary in vitro screenings on different bacterial species and cytotoxicity assessment, as well as in silico activity evaluation were performed. The obtained results confirm potential pharmacological use of this class of molecules. 相似文献