全文获取类型
收费全文 | 476篇 |
免费 | 23篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 16篇 |
2020年 | 2篇 |
2019年 | 6篇 |
2018年 | 11篇 |
2017年 | 12篇 |
2016年 | 20篇 |
2015年 | 19篇 |
2014年 | 28篇 |
2013年 | 46篇 |
2012年 | 48篇 |
2011年 | 31篇 |
2010年 | 18篇 |
2009年 | 22篇 |
2008年 | 29篇 |
2007年 | 30篇 |
2006年 | 19篇 |
2005年 | 30篇 |
2004年 | 26篇 |
2003年 | 21篇 |
2002年 | 20篇 |
2001年 | 9篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
排序方式: 共有499条查询结果,搜索用时 15 毫秒
21.
Identification of potent inhibitors of Helicoverpa armigera gut proteinases from winged bean seeds 总被引:2,自引:0,他引:2
Giri AP Harsulkar AM Ku MS Gupta VS Deshpande VV Ranjekar PK Franceschi VR 《Phytochemistry》2003,63(5):523-532
Dry mature seeds of winged bean (Psophocarpus tetragonolobus L., DC.) (WB) contain several proteinase inhibitors. Two-dimensional gel analysis of WB seed protein followed by activity visualization using a gel-X-ray film contact print technique revealed at least 14 trypsin inhibitors (TIs) in the range of 28-6 kD. A total of seven inhibitors (WBTI-1 to 7) were purified by heat treatment and gel filtration followed by elution from preparative native gels. Based on their biochemical characterization such as molecular mass, pI, heat stability, and susceptibility to inactivation by reducing agents, WBTI-1 to 4 are Kunitz type inhibitors while WBTI-5 to 7 are classified as Bowman-Birk type serine proteinase inhibitors. Although Kunitz type TIs (20-24 kD) of WB have been reported, the smaller TIs that belong to the Bowman-Birk type have not been previously characterized. Seven major TIs isolated from WB seed were individually assessed for their potential to inhibit the gut proteinases (HGP) of Helicoverpa armigera, a pest of several economically important crops, which produces at least six major and several minor trypsin/chymotrypsin/elastase-like serine proteinases in the gut. WBTI-1 (28 kD) was identified as a potent inhibitor of HGP relative to trypsin and among the other WBTIs; it inhibited 94% of HGP activity while at the same concentration it inhibited only 22% of trypsin activity. WBTI-2 (24 kD) and WBTI-4 (20 kD) inhibited HGP activity greater than 85%. WBTI-3,-5,-6 and-7 showed limited inhibition of HGP as compared with trypsin. These results indicate that WBTIs have different binding potentials towards HGP although most of the HGP activity is trypsin-like. We also developed a simple and versatile method for identifying and purifying proteinase inhibitors after two-dimensional separation using the gel-X-ray film contact print technique. 相似文献
22.
The use of high-throughput DNA sequencing and proteomic methods has led to an unprecedented increase in the amount of genomic and proteomic data. Application of computing technologies and development of computational tools to analyze and present these data has not kept pace with the accumulation of information. Here, we discuss the use of different database systems to store biological information and mention some of the key emerging computing technologies that are likely to have a key role in the future of bioinformatics. 相似文献
23.
24.
Chickpea Defensive Proteinase Inhibitors Can Be Inactivated by Podborer Gut Proteinases 总被引:4,自引:0,他引:4
Ashok P. Giri Abhay M. Harsulkar Vasanti V. Deshpande Mohini N. Sainani Vidya S. Gupta Prabhakar K. Ranjekar 《Plant physiology》1998,116(1):393-401
Developing chickpea (Cicer arietinum L.) seeds 12 to 60 d after flowering (DAF) were analyzed for proteinase inhibitor (Pi) activity. In addition, the electrophoretic profiles of trypsin inhibitor (Ti) accumulation were determined using a gel-radiographic film-contact print method. There was a progressive increase in Pi activity throughout seed development, whereas the synthesis of other proteins was low from 12 to 36 DAF and increased from 36 to 60 DAF. Seven different Ti bands were present in seeds at 36 DAF, the time of maximum podborer (Helicoverpa armigera) attack. Chickpea Pis showed differential inhibitory activity against trypsin, chymotrypsin, H. armigera gut proteinases, and bacterial proteinase(s). In vitro proteolysis of chickpea Ti-1 with various proteinases generated Ti-5 as the major fragment, whereas Ti-6 and -7 were not produced. The amount of Pi activity increased severalfold when seeds were injured by H. armigera feeding. In vitro and in vivo proteolysis of the early- and late-stage-specific Tis indicated that the chickpea Pis were prone to proteolytic digestion by H. armigera gut proteinases. These data suggest that survival of H. armigera on chickpea may result from the production of inhibitor-insensitive proteinases and by secretion of proteinases that digest chickpea Pis. 相似文献
25.
26.
Vidya Athreya Arjun Srivathsa Mahi Puri Krithi K. Karanth N. Samba Kumar K. Ullas Karanth 《PloS one》2015,10(11)
There is increasing evidence of large carnivore presence outside protected areas, globally. Although this spells conservation success through population recoveries, it makes carnivore persistence in human-use landscapes tenuous. The widespread distribution of leopards in certain regions of India typifies this problem. We obtained information on leopard-human interactions at a regional scale in Karnataka State, India, based on systematic surveys of local media reports. We applied an innovative occupancy modelling approach to map their distribution patterns and identify hotspots of livestock/human depredation. We also evaluated management responses like removals of ‘problem’ leopards through capture and translocations. Leopards occupied around 84,000 km2 or 47% of the State’s geographic area, outside designated national parks and wildlife sanctuaries. Their presence was facilitated by extent of vegetative cover- including irrigated croplands, rocky escarpments, and prey base in the form of feral and free-ranging dogs. Higher probabilities of livestock/human attacks by leopards were associated with similar ecological features as well as with capture/removals of leopards. Of the 56 cases of leopard removals reported, 91% did not involve human attacks, but followed livestock predation or only leopard sightings. The lack of knowledge on leopard ecology in human-use areas has resulted in unscientific interventions, which could aggravate the problem rather than mitigating it. Our results establish the presence of resident, breeding leopards in human-use areas. We therefore propose a shift in management focus, from current reactive practices like removal and translocation of leopards, to proactive measures that ensure safety of human lives and livelihoods. 相似文献
27.
Deidre A. Winnier Marcel Fourcaudot Luke Norton Muhammad A. Abdul-Ghani Shirley L. Hu Vidya S. Farook Dawn K. Coletta Satish Kumar Sobha Puppala Geetha Chittoor Thomas D. Dyer Rector Arya Melanie Carless Donna M. Lehman Joanne E. Curran Douglas T. Cromack Devjit Tripathy John Blangero Ravindranath Duggirala Harald H. H. G?ring Ralph A. DeFronzo Christopher P. Jenkinson 《PloS one》2015,10(4)
Type 2 diabetes (T2D) is a complex metabolic disease that is more prevalent in ethnic groups such as Mexican Americans, and is strongly associated with the risk factors obesity and insulin resistance. The goal of this study was to perform whole genome gene expression profiling in adipose tissue to detect common patterns of gene regulation associated with obesity and insulin resistance. We used phenotypic and genotypic data from 308 Mexican American participants from the Veterans Administration Genetic Epidemiology Study (VAGES). Basal fasting RNA was extracted from adipose tissue biopsies from a subset of 75 unrelated individuals, and gene expression data generated on the Illumina BeadArray platform. The number of gene probes with significant expression above baseline was approximately 31,000. We performed multiple regression analysis of all probes with 15 metabolic traits. Adipose tissue had 3,012 genes significantly associated with the traits of interest (false discovery rate, FDR ≤ 0.05). The significance of gene expression changes was used to select 52 genes with significant (FDR ≤ 10-4) gene expression changes across multiple traits. Gene sets/Pathways analysis identified one gene, alcohol dehydrogenase 1B (ADH1B) that was significantly enriched (P < 10-60) as a prime candidate for involvement in multiple relevant metabolic pathways. Illumina BeadChip derived ADH1B expression data was consistent with quantitative real time PCR data. We observed significant inverse correlations with waist circumference (2.8 x 10-9), BMI (5.4 x 10-6), and fasting plasma insulin (P < 0.001). These findings are consistent with a central role for ADH1B in obesity and insulin resistance and provide evidence for a novel genetic regulatory mechanism for human metabolic diseases related to these traits. 相似文献
28.
Ashwini V. Rajwade Ritu S. Arora Narendra Y. Kadoo Abhay M. Harsulkar Prakash B. Ghorpade Vidya S. Gupta 《Molecular biotechnology》2010,45(2):161-170
The objective of this study was to analyze the genetic relationships, using PCR-based ISSR markers, among 70 Indian flax (Linum
usitatissimum L.) genotypes actively utilized in flax breeding programs. Twelve ISSR primers were used for the analysis yielding 136 loci,
of which 87 were polymorphic. The average number of amplified loci and the average number of polymorphic loci per primer were
11.3 and 7.25, respectively, while the percent loci polymorphism ranged from 11.1 to 81.8 with an average of 63.9 across all
the genotypes. The range of polymorphism information content scores was 0.03–0.49, with an average of 0.18. A dendrogram was
generated based on the similarity matrix by the Unweighted Pair Group Method with Arithmetic Mean (UPGMA), wherein the flax
genotypes were grouped in five clusters. The Jaccard’s similarity coefficient among the genotypes ranged from 0.60 to 0.97.
When the omega-3 alpha linolenic acid (ALA) contents of the individual genotypes were correlated with the clusters in the
dendrogram, the high ALA containing genotypes were grouped in two clusters. This study identified SLS 50, Ayogi, and Sheetal
to be the most diverse genotypes and suggested their use in breeding programs and for developing mapping populations. 相似文献
29.
Kasirajan B Maruthamuthu R Gopalakrishnan V Arumugam K Asirvatham H Murali V Mohandass R Bhaskar A 《Bioinformation》2007,2(3):105-106
The knowledge of most plants used in the treatment of asthma, the plant part which is effective in treatment is confined to very few persons who are engaged in folklore medicine. However, this form of medicine is not very popular. Therefore, it is of considerable interest to ethno-botanical community to understand the plants and the parts used for treatment. Here, we describe AsthmaPlantBase, a database containing information of medicinal plants for treatment of asthma.
Availability 相似文献
30.
Anandan R Mathew S Sankar TV Viswanathan Nair PG 《Prostaglandins, leukotrienes, and essential fatty acids》2007,76(3):153-158
The protective effect of PUFA concentrate prepared from fish oil on isoproterenol-induced myocardial infarction in male albino rats was investigated with respect to changes in the levels of diagnostic marker enzymes, cholesterol, triglycerides, free fatty acids, phospholipids, reduced glutathione (GSH) and lipid peroxides (LPO). Administration of PUFA concentrate significantly prevented the isoproterenol-induced elevation in the levels of plasma diagnostic marker enzymes (ALT [93.5%], AST [95.6%], LDH [94.7%] and CPK [96.1%]). PUFA concentrate feeding exerted a significant antilipidemic effect against isoproterenol-induced myocardial infarction by reducing the levels of lipid components in plasma (cholesterol [71.5%], triglycerides [79.7%] and free fatty acids [70.7%] and heart tissue (cholesterol [81.4%], triglycerides [76.3%] and free fatty acids [78.6%]). A tendency to prevent the isoproterenol-induced phospholipids depletion (74.4%) in the myocardium of experimental rats was also observed. The level of lipid peroxidation was also found to be significantly lower in PUFA treated animals (2.72+/-0.15nmol/ml in plasma; 1.18+/-0.08nmol/mg protein in heart tissue) as compared to that of isoproterenol-injected groups (5.77+/-0.43nmol/ml in plasma; 2.14+/-0.15nmol/mg protein in heart tissue) of rats. Also the level of reduced GSH significantly higher in the heart tissue of PUFA administered experimental rats (5.65+/-0.98 microg/g) as compared to myocardial infarction induced control rats (2.39+/-0.18 microg/g). The results of the present study indicate that the overall cardioprotective effect of PUFA concentrate is probably related to its ability to inhibit lipid accumulation by its hypolipidaemic property. 相似文献