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331.
We have investigated the clinical, hematological, and molecular genetic characteristics of sickle cell anemia patients from 6 populations of Andhra Pradesh, South India. Of 72 sickle cell chromosomes (HBB*S) 60 belong to characteristic Arab-Indian haplotypes, 6 to variant Arab-Indian haplotypes, 1 to a Bantu haplotype, 2 to a Cameroon haplotype, and 3 to rare haplotypes. This is the first report of a Bantu haplotype in an Indian population. Some information on haplotype characteristics of normal chromosomes (HBB*A) is also presented. The average hemoglobin level was 7.3 g% and mean fetal hemoglobin (HbF) level was 12.6%. The higher HbF levels corroborate earlier observations in sickle cell homozygotes from India. Clinical investigations have revealed splenomegaly and painful crises as the most common features in these patients.  相似文献   
332.
Data obtained on the conversion of -glucose to alcohol using Saccharomyces cerevisiae in batch culture has been analysed kinetically. The effects of different kinetic parameters, e.g. rates of ethanol and biomass formation, rate of -glucose utilization and variation of pH have been studied. Analysis of data was made on the basis of Michaelis-Menten, Leudeking-Piret and simple kinetics. Unsteady rate behaviour in the lag phase was observed and explained.  相似文献   
333.

Background  

Molecular studies of microbial diversity have provided many insights into the bacterial communities inhabiting the human body and the environment. A common first step in such studies is a survey of conserved marker genes (primarily 16S rRNA) to characterize the taxonomic composition and diversity of these communities. To date, however, there exists significant variability in analysis methods employed in these studies.  相似文献   
334.
Data obtained on the conversion of d-glucose to alcohol using Saccharomyces cerevisiae in batch culture has been analysed kinetically. The effects of different kinetic parameters, e.g. rates of ethanol and biomass formation, rate of d-glucose utilization and variation of pH have been studied. Analysis of data was made on the basis of Michaelis-Menten, Leudeking-Piret and simple kinetics. Unsteady rate behaviour in the lag phase was observed and explained.  相似文献   
335.
Existence of variability in morphological traits and growth rate of mycelium of homokaryotic single basidiospores can be exploited for the development of inter-strainal hybrids. We isolated 182 single basidiospores from mushroom bodies of P. sajor-caju, P. florida, P. eous and one wild relative of Pleurotus called Hypsizygus ulmaris. The single spores were isolated using a new technique that is less prone to contamination and more efficient than the common techniques used by earlier workers. All the isolates showed a varied range of cultural morphology. Mating types of all the isolates within the species were identified on the basis of hyphal fusion via anastomosis with the tester strains. Four compatible pairs of isolates with well prominent tuft in the contact zone were selected for dikaryon isolation. Dikaryons were used for spawn preparation and mushroom cultivation. The dikaryotic isolates with their replicates were evaluated for spawn run period, yield and biological efficiency. 42 isolates (10 di- and 32 mono-karyotic isolates) were analyzed with RAPD genetic markers. Phenotypic characters and mating types of all the 42 isolates analyzed genetically were correlated with their genetic polymorphism data. The isolates showed very large diversity both at the phenotypic and the genotypic level. Available phenotypic and genotypic data can further help in the selection of monosporous isolates for developing inter-strainal hybrids which can lead to better prospects for genetic improvement in different species of Pleurotus.  相似文献   
336.
The levels of total and individual polyamine and arginine decarboxylase,the key enzyme of its biosynthesis, varied not only betweensource (flag leaf) and sink (spikelet) organs but also in stagesof panicle development in rice. The polyamine(s) titers increasedby 1.2 and 3-fold (approx.) in source and sink organs, respectively,at the milky stage of panicle development. However, the activityof arginine decarboxylase did not follow the same patttern,decreasing gradually in the source organ. The effects of polyamineon the Hill reaction in isolated chloroplasts and in vivo 14CO2fixation were inhibitory. The degree of inhibition in the variousdevelopmental stages depended on the concentration of the polyamines. (Received May 19, 1988; Accepted August 9, 1988)  相似文献   
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The relative binding affinity in terms of ΔΔG bind-cald value of the antimalarial compound artemisinin-quinine hybrid is primarily derived and is discussed in this article with reference to the ΔG bind-cald values of two known inhibitors Pepstatin-A and KNI-10006 complexed with HAP enzyme. The ΔG bind-cald value for KNI-10006 and Pepstatin-A is -14.10 kcal/mol and -13.09 kcal/mol respectively. The MM-GB/SA scoring results in the relative binding energy (ΔΔG bind-cald) of the hybrid molecule with respect to Pepstatin-A as 2.43 kcal/mol and 3.44 kcal/mol against KNI-10006. The overall binding mode of Art-Qui-OH resembles that of Pepstatin-A binding in HAP active site. We suggest here that the ΔΔG bind-cald value & proposed binding mode of the Art-Qui-OH for HAP enzyme should be considered for further structure-based drug design effort.  相似文献   
340.
Background:Studying protein-protein and protein-DNA interactions are prerequisites for the identification of function and mechanistic role of various proteins in the cell. Protocols for analyzing DNA-based Protein-Protein and Protein-DNA interactions are complicated and need to be simplified for efficient tracking of binding capabilities of various proteins to specific DNA molecules. Here, we demonstrated a simple yet efficient protocol for the identification of DNA coating-based Protein-DNA interaction using antibodymediated immunodetection.Methods:Briefly, we have coated specific DNA in the microtiter plate followed by incubating with protein lysate. Specific protein-DNA and/or protein-protein bind with DNA interactions are identified using specific fluorophore-conjugated antibodies. Antibodies are used to detect a protein that is bound to the DNA.Results:Fluorescent-based detection identifies the specific interaction between Protein-DNA with respect to coated DNA fragments. The protocol uses indirect conjugated antibodies and hence the technique is sensitive for effective identification of Protein-DNA interactions.Conclusion:Based on the results we conclude that the demonstrated protocol is simple, efficient and sensitive for identification of Protein-DNA interactions.Key Words: DNA coating, Lamin A, Protein-DNA interaction.  相似文献   
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