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991.
T. Moises S. Wüller S. Saxena J. Senderek A. Krüttgen 《Biochemical and biophysical research communications》2009,387(2):360-364
Neurotrophin receptors of the Trk family promote neuronal survival. The signal transduction of Trk receptors is regulated by endosomal trafficking. Monoubiquitination of receptor tyrosine kinases is an established signal for sorting of internalized receptors to late endosomes. The NGF receptor TrkA is sorted to late endosomes and undergoes ubiquitination, indicating a so far undefined regulatory role of proteasomal activity in the trafficking of TrkA. Surprisingly, we found that proteasomal inhibition alters the trafficking of TrkA from the late endosomal sorting pathway to the recycling pathway. Many neurodegenerative diseases are associated with impaired proteasomal activity. Thus, our study suggests that missorting of neurotrophic receptors might contribute to neuronal death in those neurodegenerative diseases that are known to be associated with impaired proteasomal function. 相似文献
992.
A new species of chewing louse, Myrsidea agarwali, is described from Garrulax lineatus lineatus (Passeriformes: Timaliidae) from the Rampur district (India). A key is provided for the identification of males and females
of Myrsidea from birds of the genus Garrulax. 相似文献
993.
Pritesh Gupta Kakoli DuttSwati Misra Shailendra RaghuwanshiR.K. Saxena 《Bioresource technology》2009,100(18):4074-4076
Cross-linked enzyme aggregates (CLEAs) have emerged as an interesting biocatalyst design for immobilization. Using this approach, a 1,3 regiospecific, alkaline and thermostable lipase from Thermomyces lanuginosa was immobilized. Efficient cross-linking was observed when ammonium sulphate was used as precipitant along with a two fold increase in activity in presence of SDS. The TEM and SEM microphotographs of the CLEAs formed reveal that the enzyme aggregates are larger in size as compared to the free lipase due to the cross-linking of enzyme aggregates with glutaraldehyde. The stability and reusability of the CLEA with respect to olive oil hydrolysis was evaluated. The CLEA showed more than 90% residual activity even after 10 cycles of repeated use. 相似文献
994.
In systems and computational biology, much effort is devoted to functional identification of systems and networks at the molecular-or cellular scale. However, similarly important networks exist at anatomical scales such as the tendon network of human fingers: the complex array of collagen fibers that transmits and distributes muscle forces to finger joints. This network is critical to the versatility of the human hand, and its function has been debated since at least the 16th century. Here, we experimentally infer the structure (both topology and parameter values) of this network through sparse interrogation with force inputs. A population of models representing this structure co-evolves in simulation with a population of informative future force inputs via the predator-prey estimation-exploration algorithm. Model fitness depends on their ability to explain experimental data, while the fitness of future force inputs depends on causing maximal functional discrepancy among current models. We validate our approach by inferring two known synthetic Latex networks, and one anatomical tendon network harvested from a cadaver''s middle finger. We find that functionally similar but structurally diverse models can exist within a narrow range of the training set and cross-validation errors. For the Latex networks, models with low training set error [<4%] and resembling the known network have the smallest cross-validation errors [∼5%]. The low training set [<4%] and cross validation [<7.2%] errors for models for the cadaveric specimen demonstrate what, to our knowledge, is the first experimental inference of the functional structure of complex anatomical networks. This work expands current bioinformatics inference approaches by demonstrating that sparse, yet informative interrogation of biological specimens holds significant computational advantages in accurate and efficient inference over random testing, or assuming model topology and only inferring parameters values. These findings also hold clues to both our evolutionary history and the development of versatile machines. 相似文献
995.
Varshney RK Chen W Li Y Bharti AK Saxena RK Schlueter JA Donoghue MT Azam S Fan G Whaley AM Farmer AD Sheridan J Iwata A Tuteja R Penmetsa RV Wu W Upadhyaya HD Yang SP Shah T Saxena KB Michael T McCombie WR Yang B Zhang G Yang H Wang J Spillane C Cook DR May GD Xu X Jackson SA 《Nature biotechnology》2012,30(1):83-89
Pigeonpea is an important legume food crop grown primarily by smallholder farmers in many semi-arid tropical regions of the world. We used the Illumina next-generation sequencing platform to generate 237.2 Gb of sequence, which along with Sanger-based bacterial artificial chromosome end sequences and a genetic map, we assembled into scaffolds representing 72.7% (605.78 Mb) of the 833.07 Mb pigeonpea genome. Genome analysis predicted 48,680 genes for pigeonpea and also showed the potential role that certain gene families, for example, drought tolerance-related genes, have played throughout the domestication of pigeonpea and the evolution of its ancestors. Although we found a few segmental duplication events, we did not observe the recent genome-wide duplication events observed in soybean. This reference genome sequence will facilitate the identification of the genetic basis of agronomically important traits, and accelerate the development of improved pigeonpea varieties that could improve food security in many developing countries. 相似文献
996.
Swati Misra Shailendra Raghuwanshi Pritesh Gupta R. K. Saxena 《Biotechnology and Bioprocess Engineering》2012,17(2):398-406
The experiment described in this paper synthesizes xylitol acylated products from fermentative derived xylitol and acid anhydrides
of various chain lengths in the presence of Tetrahydrofuran (THF) and acetonitrile using immobilized Pseudomonas aeruginosa (PL) lipase as a biocatalyst (97% residual activity up to five cycles) at 37°C, 200 rpm. This study examines a number of
different acid anhydrides for their highly selective and efficient lipase-catalyzed acylation of primary hydroxyl groups in
xylitol. Of those studied, the best results are obtained with butanoic anhydride, 80.12% after 4 h in acetonitrile followed
by vinyl acetate, which results in 77.79% conversion after 8 h of incubation in THF as analyzed through high performance liquid
chromatography (HPLC). 相似文献
997.
Impact of PGPR inoculation on growth and antioxidant status of wheat under saline conditions 总被引:2,自引:0,他引:2
Two plant growth‐promoting rhizobacterial (PGPR) strains, Bacillus subtilis SU47 and Arthrobacter sp. SU18, were found to tolerate 8% NaCl. Wheat co‐inoculated with these two PGPR strains, and grown under different salinity regimes (2–6 dS m?1), showed an increase in dry biomass, total soluble sugars and proline content. Wheat sodium content was reduced under co‐inoculated conditions but not after single inoculation with either strain or in the control. The activity of antioxidant enzymes in wheat leaves decreased under salinity stress after PGPR co‐inoculation, suggesting these PGPR species could be used for amelioration of stress in wheat plants. Activity of three antioxidant enzymes in wheat grown with both PGPR strains was reduced, most notably that of catalase activity at a salinity of 6 dS m?1, when compared with the control. The results indicate that co‐inoculation with B. subtilis and Arthrobacter sp. could alleviate the adverse effects of soil salinity on wheat growth. 相似文献
998.
Bhoo-Pathy N Hartman M Yip CH Saxena N Taib NA Lim SE Iau P Adami HO Bulgiba AM Lee SC Verkooijen HM 《PloS one》2012,7(2):e30995
Background
The burden of breast cancer in Asia is escalating. We evaluated the impact of ethnicity on survival after breast cancer in the multi-ethnic region of South East Asia.Methodology/Principal Findings
Using the Singapore-Malaysia hospital-based breast cancer registry, we analyzed the association between ethnicity and mortality following breast cancer in 5,264 patients diagnosed between 1990 and 2007 (Chinese: 71.6%, Malay: 18.4%, Indian: 10.0%). We compared survival rates between ethnic groups and calculated adjusted hazard ratios (HR) to estimate the independent effect of ethnicity on survival. Malays (n = 968) presented at a significantly younger age, with larger tumors, and at later stages than the Chinese and Indians. Malays were also more likely to have axillary lymph node metastasis at similar tumor sizes and to have hormone receptor negative and poorly differentiated tumors. Five year overall survival was highest in the Chinese women (75.8%; 95%CI: 74.4%–77.3%) followed by Indians (68.0%; 95%CI: 63.8%–72.2%), and Malays (58.5%; 95%CI: 55.2%–61.7%). Compared to the Chinese, Malay ethnicity was associated with significantly higher risk of all-cause mortality (HR: 1.34; 95%CI: 1.19–1.51), independent of age, stage, tumor characteristics and treatment. Indian ethnicity was not significantly associated with risk of mortality after breast cancer compared to the Chinese (HR: 1.14; 95%CI: 0.98–1.34).Conclusion
In South East Asia, Malay ethnicity is independently associated with poorer survival after breast cancer. Research into underlying reasons, potentially including variations in tumor biology, psychosocial factors, treatment responsiveness and lifestyle after diagnosis, is warranted. 相似文献999.
Moorthy NS Saxena V Karthikeyan C Trivedi P 《Journal of enzyme inhibition and medicinal chemistry》2012,27(2):201-207
A series of 1,2,4-trisubstituted 5-imidazolinone derivatives were synthesized by Erlenmeyer condensation of benzoylglycine (hippuric acid) with different aldehydes in the presence of sodium acetate and acetic anhydride. The derivatives of the compounds were prepared by condensation of some known sulpha drugs with 5-oxazolone derivatives. The anticonvulsant activity of the compounds was determined by the protection of pentylenetetrazole-induced convulsions that was ranged from 10 to 60%. The compounds with p-OCH?, p-OH and o-Cl substitutions in the phenyl ring on 4(th) position of the imidazolinone ring exhibited good anticonvulsant activity. In silico metabolic and toxicity studies showed that all the compounds in the series are not likely to exhibit toxicity except the compounds IIIa, IIIb, VIa and VIb, that is predicted to show 29% mutagenicity and 53% irritation in comparison to the other compounds. The predicted lethal effect and hERG toxicity of the compounds showed that IIa, IVa, Va and Vb might be toxic at higher concentrations. The results successfully establish the synthesized imidazolinone derivatives as novel compounds with anticonvulsant properties, low predicted cardiotoxicity and lethal effects thus can be promising leads for further development as novel anticonvulsants. 相似文献
1000.
Sandeep Singh Tianfu Wu Chun Xie Kamala Vanarsa Jie Han Tina Mahajan Ho Bing Oei Chul Ahn Xin J Zhou Chaim Putterman Ramesh Saxena Chandra Mohan 《Arthritis research & therapy》2012,14(4):R164