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41.
42.
Ashwin A. Raut Anil Kumar Sheo N. Kala Vinod Chhokar Neeraj Rana Vikas Beniwal Sundeep Jaglan Sachin K. Samuchiwal Jitender K. Singh Anamika Mishra 《Genetics and molecular biology》2012,35(3):610-613
Diacylglycerol O-acyltransferase 1 (DGAT1) is a microsomal enzyme that catalyzes the final step of triglyceride synthesis. The DGAT1 gene is a strong functional candidate for determining milk fat content in cattle. In this work, we used PCR-SSCP (polymerase chain reaction-single-strand conformation polymorphism) and DNA sequencing to examine polymorphism in the region spanning exon 7 to exon 9 of the DGAT1 gene in Murrah and Pandharpuri buffaloes. Three alleles (A, B and C) and four novel single-nucleotide polymorphisms were identified in the buffalo DGAT1 gene. The frequencies of the alleles differed between the two buffalo breeds, with allele C being present in Murrah but not in Pandharpuri buffalo. The allele variation detected in this work may influence DGAT1 expression and function. The results described here could be useful in examining the association between the DGAT1 gene and milk traits in buffalo. 相似文献
43.
Ashish T. Baviskar Uttam C. Banerjee Mukesh Gupta Rajveer Singh Sunil Kumar Manish K. Gupta Sanjeev Kumar Satish K. Raut Madhu Khullar Sandeep Singh Raj Kumar 《Bioorganic & medicinal chemistry》2013,21(18):5782-5793
Design, synthesis and anticancer activity of a series of imine-pyrazolopyrimidinones is reported for the first time. Compounds 9d, 9n and 9o in the series show encouraging in vitro anticancer activity with low micromolar IC50 values against prostate (PC3) and breast (MCF7) cancer cell lines. Some notions about structure–activity relationships and plausible mechanism of biological activity are presented. 相似文献
44.
Rosemary J Redfield Wendy A Findlay Janine Bossé J Simon Kroll Andrew DS Cameron John HE Nash 《BMC evolutionary biology》2006,6(1):82-15
Background
Many bacteria can take up DNA, but the evolutionary history and function of natural competence and transformation remain obscure. The sporadic distribution of competence suggests it is frequently lost and/or gained, but this has not been examined in an explicitly phylogenetic context. Additional insight may come from the sequence specificity of uptake by species such as Haemophilus influenzae, where a 9 bp uptake signal sequence (USS) repeat is both highly overrepresented in the genome and needed for efficient DNA uptake. We used the distribution of competence genes and DNA uptake specificity in H. influenzae 's family, the Pasteurellaceae, to examine the ancestry of competence. 相似文献45.
Significant increase in the salivary gland weight was observed after exposure to single therapeutic dose of 3.7 MBq of 131I in mice. Pre-supplementation of antioxidants, O. sanctum leaf extract, turmeric extract and vitamin E for 15 days before 131I exposure demonstrated significant reduction in the salivary gland weight. No major histopathological changes were observed in the salivary gland of experimental animals at 24 h of exposure. Micronuclei index in the bone marrow of polychromatic (PCEs) and normochromatic erythrocytes (NCEs) remained unchanged in all the experimental groups. However, PCE/NCE ratio in the bone marrow decreased significantly in all the 131I exposed animals irrespective of antioxidant supplementation status. The normalization of salivary gland weight by antioxidant pre-supplementation in radioiodine exposed mice is suggestive of the possible ameliorating effect of antioxidants on the salivary gland weight recommending further detailed studies regarding the functional aspect of the salivary gland in higher animals. 相似文献
46.
Parent presence, delayed dispersal, and territory acquisition in the Seychelles warbler 总被引:1,自引:0,他引:1
The presence of parents in the natal territory may play an important,but often overlooked, role in natal dispersal and the consequentacquisition of a territory. Living with parents in a territorymay confer a fitness advantage to subordinates through, forexample, the nepotistic behavior of the parents or indirectbenefits gained by helping to raise nondescendent kin. Whena parent is replaced by a stepparent, such advantages are reducedor disappear and, as a result, subordinates may disperse. Subordinatesthat disperse after parent replacement may be constrained intheir timing of dispersal, which could have negative fitnessconsequences. In the cooperatively breeding Seychelles warbler,we show that when a parent was naturally replaced or experimentallyremoved and subsequently replaced by a stepparent from outsidethe territory, subordinates were more likely to disperse thanwhen both parents remained in the natal territory. Furthermore,subordinates dispersing from territories in which one or bothparents had been replaced were less likely to acquire a breederposition than subordinates dispersing when both parents werestill on the natal territory. Our findings suggest that thepresence of parents in the natal territory may promote delayeddispersal and facilitate the eventual acquisition of a breederposition outside the natal territory. Our results support theidea that the prolonged parental care, which long-lived speciesare able to provide, may have selected for family living. 相似文献
47.
Shiradkar MR Murahari KK Gangadasu HR Suresh T Kalyan CA Panchal D Kaur R Burange P Ghogare J Mokale V Raut M 《Bioorganic & medicinal chemistry》2007,15(12):3997-4008
In the present study, a series of N-{4-[(4-amino-5-sulfanyl-4H-1,2,4-triazol-3-yl)methyl]-1,3-thiazol-2-yl}-2-substituted-amide (1a-d) derivatives were synthesized in good yields and characterized by IR, 1H NMR, mass spectral and elemental analyses. The compounds were evaluated for their preliminary in vitro antibacterial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhosa and then were screened for antitubercular activity against Mycobacterium tuberculosis H37 Rv strain by broth microdilution assay method. The antibacterial data of the tested compounds indicated that most of the synthesized compounds showed better activity against bacteria compared to reference drugs. The in vitro antitubercular activity reports of tested compounds against M. tuberculosis strain H37 Rv showed moderate to better activity. 相似文献
48.
Background and Scope
In eukaryotes, chromatin remodelling complexes are shown to be responsible for nucleosome mobility, leading to increased accessibility of DNA for DNA binding proteins. Although the existence of such complexes in plants has been surmised mainly at the genetic level from bioinformatics studies and analysis of mutants, the biochemical existence of such complexes has remained unexplored.Methods
Histone H1-depleted donor chromatin was prepared by micrococcal nuclease digestion of wheat nuclei and fractionation by exclusion chromatography. Nuclear extract was partially purified by cellulose phosphate ion exchange chromatography. Histone octamer trans-transfer activity was analysed using the synthetic nucleosome positioning sequence in the absence and presence of ATP and its analogues. ATPase activity was measured as 32Pi released using liquid scintillation counting.Key Results
ATP-dependent histone octamer trans-transfer activity, partially purified from wheat nuclei using cellulose phosphate, showed ATP-dependent octamer displacement in trans from the H1-depleted native donor chromatin of wheat to the labelled synthetic nucleosome positioning sequence. It also showed nucleosome-dependent ATPase activity. Substitution of ATP by ATP analogues, namely ATPγS, AMP-PNP and ADP abolished the octamer trans-transfer, indicating the requirement of ATP hydrolysis for this activity.Conclusions
ATP-dependent histone octamer transfer in trans is a recognized activity of chromatin remodelling complexes required for chromatin structure dynamics in non-plant species. Our results suggested that wheat nuclei also possess a typical chromatin remodelling activity, similar to that in other eukaryotes. This is the first report on chromatin remodelling activity in vitro from plants. 相似文献49.
JC Kwong S Ratnasingham MA Campitelli N Daneman SL Deeks DG Manuel VG Allen AM Bayoumi A Fazil DN Fisman AS Gershon E Gournis EJ Heathcote FB Jamieson P Jha KM Khan SE Majowicz T Mazzulli AJ McGeer MP Muller A Raut E Rea RS Remis R Shahin AJ Wright B Zagorski NS Crowcroft 《PloS one》2012,7(9):e44103
Background
Evidence-based priority setting is increasingly important for rationally distributing scarce health resources and for guiding future health research. We sought to quantify the contribution of a wide range of infectious diseases to the overall infectious disease burden in a high-income setting.Methodology/Principal Findings
We used health-adjusted life years (HALYs), a composite measure comprising premature mortality and reduced functioning due to disease, to estimate the burden of 51 infectious diseases and associated syndromes in Ontario using 2005–2007 data. Deaths were estimated from vital statistics data and disease incidence was estimated from reportable disease, healthcare utilization, and cancer registry data, supplemented by local modeling studies and national and international epidemiologic studies. The 51 infectious agents and associated syndromes accounted for 729 lost HALYs, 44.2 deaths, and 58,987 incident cases per 100,000 population annually. The most burdensome infectious agents were: hepatitis C virus, Streptococcus pneumoniae, Escherichia coli, human papillomavirus, hepatitis B virus, human immunodeficiency virus, Staphylococcus aureus, influenza virus, Clostridium difficile, and rhinovirus. The top five, ten, and 20 pathogens accounted for 46%, 67%, and 75% of the total infectious disease burden, respectively. Marked sex-specific differences in disease burden were observed for some pathogens. The main limitations of this study were the exclusion of certain infectious diseases due to data availability issues, not considering the impact of co-infections and co-morbidity, and the inability to assess the burden of milder infections that do not result in healthcare utilization.Conclusions/Significance
Infectious diseases continue to cause a substantial health burden in high-income settings such as Ontario. Most of this burden is attributable to a relatively small number of infectious agents, for which many effective interventions have been previously identified. Therefore, these findings should be used to guide public health policy, planning, and research. 相似文献50.
Candida albicans has the ability to colonize various materials used in prostheses. In this report, we have studied the kinetics of biofilm formation on prosthetic materials and their susceptibility to fluconazole at various stages of development. Results indicated that C. albicans efficiently adheres to and colonizes polystyrene, polyvinylchloride, silicon, and polycarbonate surfaces. Candida albicans biofilm formation was observed to be both strain- and substrate dependent. Adhesion of cells to solid substrates was found sufficient to induce fluconazole resistance. Drug susceptibility at different stages of biofilm growth showed that Candida biofilms on these substrates are highly resistant to fluconazole. The study focuses on the limitations of fluconazole to combat biofilm-related infections and emphasizes the need for better therapeutic strategies against prosthesis-associated C. albicans infections. 相似文献