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891.
892.
In vitro effects of 28-homobrassinolide (HBl) were evaluated on morphological and biochemical parameters of susceptible (Pusa Ruby) and resistant (PNR-7) cultivars of tomato, 5 days after nematode inoculation. In susceptible cultivar, nematode invasion reduced the plant growth while growth was enhanced after brassinosteroid treatment. In case of resistant plants, nematodes were not able to invade the roots and here also, pre-sowing treatment of seeds with HBl further enhanced the growth of plants. An increase in specific activities of antioxidative enzymes (catalase, ascorbate peroxidase, guaiacol peroxidase, glutathione reductase, glutathione peroxidase and superoxide dismutase) was observed in susceptible plants treated with HBl. In resistant cultivar, nematode inoculation increased the specific activities which were further enhanced with HBl treatment. The results obtained in the present study indicated the ameliorative effects on tomato varieties treated with HBl even after nematode stress. Thus, suggesting a possible role of HBl in lessening the oxidative stress generated during nematode invasion and boosting the resistance capacity of plants. 相似文献
893.
Chirag J. Patel Rong Chen Keiichi Kodama John P. A. Ioannidis Atul J. Butte 《Human genetics》2013,132(5):495-508
Diseases such as type 2 diabetes (T2D) result from environmental and genetic factors, and risk varies considerably in the population. T2D-related genetic loci discovered to date explain only a small portion of the T2D heritability. Some heritability may be due to gene–environment interactions. However, documenting these interactions has been difficult due to low availability of concurrent genetic and environmental measures, selection bias, and challenges in controlling for multiple hypothesis testing. Through genome-wide association studies (GWAS), investigators have identified over 90 single nucleotide polymorphisms (SNPs) associated to T2D. Using a method analogous to GWAS [environment-wide association study (EWAS)], we found five environmental factors associated with the disease. By focusing on risk factors that emerge from GWAS and EWAS, it is possible to overcome difficulties in uncovering gene–environment interactions. Using data from the National Health and Nutrition Examination Survey (NHANES), we screened 18 SNPs and 5 serum-based environmental factors for interaction in association to T2D. We controlled for multiple hypotheses using false discovery rate (FDR) and Bonferroni correction and found four interactions with FDR <20 %. The interaction between rs13266634 (SLC30A8) and trans-β-carotene withstood Bonferroni correction (corrected p = 0.006, FDR <1.5 %). The per-risk-allele effect sizes in subjects with low levels of trans-β-carotene were 40 % greater than the marginal effect size [odds ratio (OR) 1.8, 95 % CI 1.3–2.6]. We hypothesize that impaired function driven by rs13266634 increases T2D risk when combined with serum levels of nutrients. Unbiased consideration of environmental and genetic factors may help identify larger and more relevant effect sizes for disease associations. 相似文献
894.
Abhijit Chakraborty Atul Katarkar Keya Chaudhuri Ashis Mukhopadhyay Jayasri Basak 《Cellular & molecular biology letters》2013,18(4):631-638
Hereditary breast cancer constitutes 5–10% of all breast cancer cases. Inherited mutations in the BRCA1 and BRCA2 tumor-suppressor genes account for the majority of hereditary breast cancer cases. The BRCA1 C-terminal region (BRCT) has a functional duplicated globular domain, which helps with DNA damage repair and cell cycle checkpoint protein control. More than 100 distinct BRCA1 missense variants with structural and functional effects have been documented within the BRCT domain. Interpreting the results of mutation screening of tumor-suppressor genes that can have high-risk susceptibility mutations is increasingly important in clinical practice. This study includes a novel mutation, p.His1746 Pro (c.5237A>C), which was found in BRCA1 exon 20 of a breast cancer patient. In silico analysis suggests that this mutation could alter the stability and orientation of the BRCT domain and the differential binding of the BACH1 substrate. 相似文献
895.
Atul Bhardwaj Jatinder Kaur Sai Kiran Sharma Zhangjian Huang Frank Wuest Edward E. Knaus 《Bioorganic & medicinal chemistry letters》2013,23(1):163-168
The observation that the cyclooxygenase-2 (COX-2) isozyme is over-expressed in multiple types of cancer, relative to that in adjacent non-cancerous tissue, prompted this investigation to prepare a group of hybrid fluorescent conjugates wherein the COX inhibitors ibuprofen, (S)-naproxen, acetyl salicylic acid, a chlororofecoxib analog and celecoxib were coupled via a linker group to an acridone, dansyl or rhodamine B fluorophore. Within this group of compounds, the ibuprofen-acridone conjugate (10) showed potent and selective COX-2 inhibition (COX-2 IC50 = 0.67 μM; SI = 110.6), but its fluorescence emission (λem = 417, 440 nm) was not suitable for fluorescent imaging of cancer cells that over-express the COX-2 isozyme. In comparison, the celecoxib-dansyl conjugate (25) showed a slightly lower COX-2 potency and selectivity (COX-2 IC50 = 1.1 μM; SI > 90) than the conjugate 10, and it possesses a better fluorescence emission (λem = 500 nm). Ultimately, a celecoxib-rhodamine B conjugate (28) that exhibited moderate COX-2 potency and selectivity (COX-2 IC50 = 3.9 μM; SI > 25) having the best fluorescence emission (λem = 580 nm) emerged as the most promising biomarker for fluorescence imaging using a colon cancer cell line that over-expresses the COX-2 isozyme. 相似文献
896.
Hardesh K. Maurya Ruby Verma Saba Alam Shweta Pandey Vinay Pathak Sandeep Sharma Kishore K. Srivastava Arvind S. Negi Atul Gupta 《Bioorganic & medicinal chemistry letters》2013,23(21):5844-5849
Various substituted 5,6-dihydro-8-methoxybenzo[h]quinazolin-2-amine, 1-(3-(4-alkoxyphenyl)-7-methoxy-3,3a,4,5-tetrahydro-2H benzo[g]indazol-2-yl)ethanone, pyrazole and 2,6-diarylpyridine derivatives have been synthesized in good yields by an efficient methodology. The synthesized compounds (4–23) were evaluated for their in vitro anti-tubercular activity against Mycobacterium tuberculosis H37Rv strain. Compounds 6a, 6c, 8a, 19a and 19e exhibited significant anti-tubercular activity at MIC values 50, 100, 50, 25 and 100 μM concentration. In vitro cytotoxicity data using THP-1 cells indicated that most active compound 19a is safe as its MIC value is much lower than the cytotoxic value. 相似文献
897.
Himangshu Sonowal Atul Kumar Jina Bhattacharyya Pabitra Kumar Gogoi Bithiah Grace Jaganathan 《Journal of biomedical science》2013,20(1):71
Background
Mesenchymal Stem Cells (MSC) are important candidates for therapeutic applications due to their ex vivo proliferation and differentiation capacity. MSC differentiation is controlled by both intrinsic and extrinsic factors and actin cytoskeleton plays a major role in the event. In the current study, we tried to understand the initial molecular mechanisms and pathways that regulate the differentiation of MSC into osteocytes or adipocytes.Results
We observed that actin modification was important during differentiation and differentially regulated during adipogenesis and osteogenesis. Initial disruption of actin polymerization reduced further differentiation of MSC into osteocytes and osteogenic differentiation was accompanied by increase in ERK1/2 and p38 MAPK phosphorylation. However, only p38 MAPK phosphorylation was down regulated upon inhibition of actin polymerization which as accompanied by decreased CD49E expression.Conclusion
Taken together, our results show that actin modification is a pre-requisite for MSC differentiation into osteocytes and adipocytes and osteogenic differentiation is regulated through p38 MAPK phosphorylation. Thus by modifying their cytoskeleton the differentiation potential of MSC could be controlled which might have important implications for tissue repair and regeneration. 相似文献898.
Maya Kumari Atul Grover Patade Vikas Yadav Mohammad Arif Zakwan Ahmed 《Genes & genomics.》2013,35(5):661-670
Jatropha curcas L. is gaining importance as a potential energy crop. However, lack of sufficient numbers of molecular markers hinder current research on crop improvement in Jatropha. The expressed sequences tags (EST) sequences deposited in public databases, offers an excellent opportunity to identify simple sequence repeats (SSRs) through data mining, for further research on molecular breeding. In the present study 42,477 ESTs of J. curcas were screened, out of which 5,673 SSRs were identified with 48.8 % simple (excluding mononucleotide repeats) and 52.2 % compound repeat motifs. Amongst these repeat motifs, dinucleotide repeats were abundant (26.5 %), followed by trinucleotide (23.1 %) and tetranucleotide repeats (0.8 %). From these microsatellites, 32 EST-SSR (genic microsatellite) primer pairs were designed. These primers were used to analyze the genetic diversity among 42 accessions collected from different parts of India. Out of the 32 EST-SSR primers, 24 primer pairs exhibited polymorphism among the genotypes, with amplicons varying from one to eight, giving an average of 2.33 alleles per polymorphic marker. Polymorphic information content value ranged from 0.02 to 0.5 with an average of 0.402 indicating moderate level of informativeness within these EST-SSRs markers. The EST-SSR markers developed here will serve as a valuable resource for genetic studies, like linkage mapping, diversity analysis, quantitative trait locus/association mapping, and molecular breeding. The current study also revealed low diversity in the screened Indian Jatropha germplasm. Therefore, the future efforts must be made to broaden the gene pool of Jatropha for the creation of genetic diversity that can be further used for crop improvement through breeding. 相似文献
899.
Venkatraman Ramanujam Sunita Patel Atul K. Srivastava Yogendra Sharma Kandala V. R. Chary 《Biomolecular NMR assignments》2013,7(2):221-224
The sequence specific backbone 1H, 13C and 15N resonance assignments of an intrinsically unstructured βγ-crystallin from Hahella chejuensis are reported. The secondary structure chracterization of the unstructured protein reveals that large fraction of residues exhibits β-strand propensity, as in the case of the Ca2+-bound structured protein. 相似文献
900.
Shiladitya Chattopadhyay Trayambak Basak Mukti Kant Nayak Gourav Bhardwaj Anupam Mukherjee Rahul Bhowmick Shantanu Sengupta Oishee Chakrabarti Nabendu S. Chatterjee Mamta Chawla-Sarkar 《PloS one》2013,8(2)
Rotavirus (RV) being the major diarrhoegenic virus causes around 527000 children death (<5years age) worldwide. In cellular environment, viruses constantly adapt and modulate to survive and replicate while the host cell also responds to combat the situation and this results in the differential regulation of cellular proteins. To identify the virus induced differential expression of proteins, 2D-DIGE (Two-dimensional Difference Gel Electrophoresis) based proteomics was used. For this, HT-29 cells were infected with RV strain SA11 for 0 hours, 3 hours and 9 hours post infection (hpi), differentially expressed spots were excised from the gel and identified using MALDI-TOF/TOF mass spectrometry. 2D-DIGE based proteomics study identified 32 differentially modulated proteins, of which 22 were unique. Some of these were validated in HT-29 cell line and in BALB/c mice model. One of the modulated cellular proteins, calmodulin (CaM) was found to directly interact with RV protein VP6 in the presence of Ca2+. Ca2+-CaM/VP6 interaction positively regulates RV propagation since both CaM inhibitor (W-7) and Ca2+ chelator (BAPTA-AM) resulted in decreased viral titers. This study not only identifies differentially modulated cellular proteins upon infection with rotavirus in 2D-DIGE but also confirmed positive engagement of cellular Ca2+/CaM during viral pathogenesis. 相似文献