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141.
Archana Singh Garima Malik Rangoli Aggarwal Kunal Pratap Mohan R. Wani Suresh B. Gokhale Vivek T. Natarajan Rajesh S. Gokhale 《Pigment cell & melanoma research》2016,29(4):465-469
Vitiligo is a multifactorial acquired depigmenting disorder. Recent insights into the molecular mechanisms driving the gradual destruction of melanocytes in vitiligo will likely lead to the discovery of novel therapies, which need to be evaluated in animal models that closely recapitulate the pathogenesis of human vitiligo. In humans, vitiligo is characterized by a spontaneous loss of functional melanocytes from the epidermis, but most animal models of vitiligo are either inducible or genetically programmed. Here, we report that acquired depigmentation in water buffalo recapitulates molecular, histological, immunohistochemical, and ultrastructural changes observed in human vitiligo and hence could be used as a model to study vitiligo pathogenesis and facilitate the discovery and evaluation of therapeutic interventions for vitiligo. 相似文献
142.
Pratap K. Das Ranjan Chakrabarti Sandip Bandopadhyay Tushar K. Ray 《Molecular and cellular biochemistry》1989,91(1-2):123-129
A heat-labile, non-dialysable and protease-sensitive endogenous activator (NaAF) capable of stimulating the Na+, K+-ATPase system has been demonstrated. The activator (NaAF) activity was partially enriched (about 10 fold) by dialysis (30 kDa cutoff) under negative pressure and pH 4.8 precipitation. The NaAF has been found to occur in the cytosolic fractions of tissues such as the kidney and brain from two different species (rabbit and pig) tested so far. Also, the factor from one tissue stimulates with equal efficacy the Na+, K+-ATPase systems of other tissues regardless of the species; thus demonstrating universal nature of the activator. Some degree of cross-reactivity was noted between the activating effects of this activator (for the Na+,K+-ATPase) and that for the H+,K+-ATPase recently described (J. Biol. Chem. 262:5664–5670, 1987). The purified NaAF obtained from sephacryl S-300 column chromatography activates the pure renal medullary Na+,K+-ATPase in a dose dependent manner.A preliminary account of this work was published in Fed. Proc. 46(4): 4466, 1987 相似文献
143.
Determining woodpecker diversity in the sub‐Himalayan forests of northern India using call playbacks
ABSTRACT Tropical forests have exceptional woodpecker diversity, but little is known about the abundance and diversity of woodpeckers in the Indian subcontinent, particularly for the Shorea robusta‐dominated moist deciduous forests of northern India. Our objective was to compare the number of woodpecker species and number of individuals detected using playback surveys and visual/aural transect surveys at five sites. Each site was surveyed 5–6 times along a 2000‐m transect, with woodpeckers detected using two methods: (1) visual and aural cues, and (2) playing back calls of 13 species at 400‐m intervals. Both methods involved similar effort per survey (100–110 min). During surveys, we detected 11 species of woodpeckers. More species and more than twice as many individuals were detected during playback surveys than during visual/aural surveys. In addition, species accumulation curves showed that we detected the species known to be present based on previous work faster with playback surveys than with visual/aural surveys at four of the five sites. During field trials, 97% of targeted individuals (N= 269) of 12 species responded to playback, and 83% of the responses occurred within 1 min of broadcast. The number of species of woodpeckers in our study area (11 species) was typical for a structurally diverse, tropical/subtropical moist broad‐leaved forest. Our results demonstrate that playback surveys are more efficient and accurate than visual/aural surveys, and that playback surveys can be useful for assessing and monitoring woodpecker diversity in tropical forests. 相似文献
144.
145.
Pepsinogen polymorphism in the Indian population and its association with duodenal ulcer 总被引:1,自引:0,他引:1
A. Venkateshwari A. Vidyasagar Rupender Prasad Bajrang Pratap N. Pratibha 《Human genetics》1997,101(2):201-204
To date, there have been few studies on pepsinogen polymorphism. The present study examines the polymorphism of pepsinogen
by PAGE in 155 duodenal ulcer cases and 92 control subjects. The Indian population presents a higher frequency of the B phenotype
(associated with absence of the pg 5 fraction) and the C haplotype compared to other populations. Heterozygotes, in particular
AC phenotypic individuals, are found to be associated significantly with the disease compared to control subjects. All the
genes of the multigene complex controlling pepsinogen polymorphism seem to be interacting, thereby leading to such an association.
Thus, studies at the gene level may be helpful in explaining the genetic etiology and heterogeneity of duodenal ulcer disease.
Received: 15 August 1996 / Accepted: 18 July 1997 相似文献
146.
Pratap C. Dutta 《American journal of physical anthropology》1972,36(3):391-396
The biometric data on 72 usable adult skulls excavated at Harappa and dated ca. 2500-1700 bc have been re-examined in the light of the genetic concept of “population.” The original study of the material considered separately and independently the various samples from locally differentiated cultural deposits, Cemetery R37, Area G, Cemetery H, etc., and used the typologic concept of racial analysis, a traditional method now sterile. One of the major findings of the study, postulating hypothetical original races, was that a varying proportions of different racial “types” constituted each sample. The present analysis is designed, first, to identify the particular population responsible for the growth of the true Harappan culture and, secondly, to define some selected physical characters of the population. Fifteen variables provided statistical evidence that the pooled remains of Cemetery R37 and Area G can be considered as a sufficiently homogeneous Harappan population. Further, in the absence of statistically significant differences in separate measurements, the entire material may be regarded as representing the Bronze-Age Harappans. Accordingly, some selected cranio-facial features of the population have been described. 相似文献
147.
Verma Preeti Varshney Ritu Yadav Shiv Pratap Singh Kar Bibekananda Roy Partha Sharma Ashwani K. 《The protein journal》2022,41(3):381-393
The Protein Journal - A class of plant defense and storage proteins, including Putranjiva roxburghii PNP protein (PRpnp), belongs to PNP-UDP family. The PRpnp and related plant proteins contain a... 相似文献
148.
Liliana Losada Janyce A. Sugui Michael A. Eckhaus Yun C. Chang Stephanie Mounaud Abigail Figat Vinita Joardar Suman B. Pakala Suchitra Pakala Pratap Venepally Natalie Fedorova William C. Nierman Kyung J. Kwon-Chung 《PLoS pathogens》2015,11(4)
Invasive aspergillosis (IA) due to Aspergillus fumigatus is a major cause of mortality in immunocompromised patients. The discovery of highly fertile strains of A. fumigatus opened the possibility to merge classical and contemporary genetics to address key questions about this pathogen. The merger involves sexual recombination, selection of desired traits, and genomics to identify any associated loci. We constructed a highly fertile isogenic pair of A. fumigatus strains with opposite mating types and used them to investigate whether mating type is associated with virulence and to find the genetic loci involved in azole resistance. The pair was made isogenic by 9 successive backcross cycles of the foundational strain AFB62 (MAT1-1) with a highly fertile (MAT1-2) progeny. Genome sequencing showed that the F9
MAT1-2 progeny was essentially identical to the AFB62. The survival curves of animals infected with either strain in three different animal models showed no significant difference, suggesting that virulence in A. fumigatus was not associated with mating type. We then employed a relatively inexpensive, yet highly powerful strategy to identify genomic loci associated with azole resistance. We used traditional in vitro drug selection accompanied by classical sexual crosses of azole-sensitive with resistant isogenic strains. The offspring were plated under varying drug concentrations and pools of resulting colonies were analyzed by whole genome sequencing. We found that variants in 5 genes contributed to azole resistance, including mutations in erg11A (cyp51A), as well as multi-drug transporters, erg25, and in HMG-CoA reductase. The results demonstrated that with minimal investment into the sequencing of three pools from a cross of interest, the variation(s) that contribute any phenotype can be identified with nucleotide resolution. This approach can be applied to multiple areas of interest in A. fumigatus or other heterothallic pathogens, especially for virulence associated traits. 相似文献
149.
Raghvendra Pratap Singh Ram Nageena Singh Manish K Srivastava Alok Kumar Srivastava Sudheer Kumar Ramesh Chandra Dubey Arun Kumar Sharma 《Bioinformation》2012,8(21):1042-1046
Methylobacteria are ubiquitous in the biosphere which are capable of growing on C1 compounds such as formate, formaldehyde,
methanol and methylamine as well as on a wide range of multi-carbon growth substrates such as C2, C3 and C4 compounds due to
the methylotrophic enzymes methanol dehydrogenase (MDH). MDH is performing these functions with the help of a key protein
mxaF. Unfortunately, detailed structural analysis and homology modeling of mxaF is remains undefined. Hence, the objective of
this research is the characterization and three dimensional modeling of mxaF protein from three different methylotrophs by using
I-TASSER server. The predicted model were further optimize and validate by Profile 3D, Errat, Verifiy3-D and PROCHECK server.
Predicted and best evaluated models have been successfully deposited to PMDB database with PMDB ID PM0077505, PM0077506
and PM0077507. Active site identification revealed 11, 13 and 14 putative functional site residues in respected models. It may play a
major role during protein-protein, and protein-cofactor interactions. This study can provide us an ab-initio and detail information to
understand the structure, mechanism of action and regulation of mxaF protein. 相似文献
150.
Rakesh Sanabam Bharat Gopalrao Somkuwar Gourshyam Thingnam Sila Moirangthem Pratap Jyoti Handique Sunitibala Huidrom 《Bioinformation》2012,8(17):838-840
The rich wealth of Citrus genetic resources makes India to enjoy a remarkable position in the “Citrus belt of the world”. We have
developed CIBMAN, a unique database on Citrus biodiversity of Manipur which comprises 33 accessions collected through
extensive survey for more than three years. CIBMAN provides integrated access to Citrus species through sophisticated web interface
which has following capabilities a) morphological details, b) socio-economic details, c) taxonomic details and d) geographical
distribution. Morphological variability among Citrus accessions is due to variance in their genome which contributes to diverse
agronomical traits and diverse bioactive compounds of high value. This diverse gene pool can be potential source for genetic
improvement of existing cultivars and rootstocks. Systematic collection, characterization and conservation of the underutilized or
lesser exploited varieties is required for incorporating in breeding program and conserve the germplasm from ever going on
genetic erosion. This database will be useful for scientific validations and updating of traditional wisdom in bioprospecting aspects
especially industrialization of Citrus found in the state. Further, the features will be suited for detailed investigation on potential
medicinal and edible Citrus that make CIBMAN a powerful tool for sustainable management.