全文获取类型
收费全文 | 376篇 |
免费 | 35篇 |
出版年
2022年 | 9篇 |
2021年 | 11篇 |
2020年 | 7篇 |
2019年 | 13篇 |
2018年 | 12篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 15篇 |
2014年 | 17篇 |
2013年 | 24篇 |
2012年 | 22篇 |
2011年 | 31篇 |
2010年 | 11篇 |
2009年 | 12篇 |
2008年 | 23篇 |
2007年 | 13篇 |
2006年 | 15篇 |
2005年 | 16篇 |
2004年 | 17篇 |
2003年 | 7篇 |
2002年 | 15篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 6篇 |
1982年 | 2篇 |
1981年 | 5篇 |
1979年 | 6篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1972年 | 1篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1968年 | 3篇 |
1967年 | 4篇 |
1966年 | 2篇 |
1965年 | 2篇 |
1964年 | 1篇 |
1940年 | 1篇 |
排序方式: 共有411条查询结果,搜索用时 15 毫秒
61.
Dendrobium primulinum is an important epiphytic orchid. A successful protocol for mass multiplication and early in vitro flowering was developed. Immature embryos of 4 week after pollination exhibited about 96% germination within 30 days of culture on MS medium containing sucrose (3%) (w/v), NAA and BA (6 and 9 μM) in combination. Protocorm-like bodies (PLBs) formed from the germinating seeds on the germination medium. Rooted plantlets were formed within 2-3 wk on MS medium containing sucrose (3%), NAA and BA (3 and 12 μM in combination) where about 29 shoot/buds produced per cycle of 4 wk interval. The well rooted plantlets produced 4-5 floral buds per spike when they were maintained on MS medium containing sucrose (3%), fresh apple juice (10%) (v/v) for four wk followed by on MS medium freed of apple juice but enriched with NAA and BA (3 and 12 μM respectively). The hardened plantlets were transferred to community potting mix where the about 80% transplants survived after two months of transfer. 相似文献
62.
Bulbul Chakravarti Dr. Beerelli Seshi Wongrat Ratanaprayul Neville Dalal Lawrence Lin Alpan Raval Deb N. Chakravarti 《Proteomics》2009,9(3):580-597
Aging is a time‐dependent complex biological phenomenon observed in various organs and organelles of all living organisms. To understand the molecular mechanism of age‐associated functional loss in aging kidneys, we have analyzed the expression of proteins in the kidneys of young (19–22 wk) and old (24 months) C57/BL6 male mice using 2‐DE followed by LC‐MS/MS. We found that expression levels of 49 proteins were upregulated (p ≤ 0.05), while that of only ten proteins were downregulated (p ≤ 0.05) due to aging. The proteins identified belong to three broad functional categories: (i) metabolism (e.g., aldehyde dehydrogenase family, ATP synthase β‐subunit, malate dehydrogenase, NADH dehydrogenase (ubiquinone), hydroxy acid oxidase 2), (ii) transport (e.g., transferrin), and (iii) chaperone/stress response (e.g., Ig‐binding protein, low density lipoprotein receptor‐related protein associated protein 1, selenium‐binding proteins (SBPs)). Some proteins with unknown functions were also identified as being differentially expressed. ATP synthase β subunit, transferrin, fumarate hydratase, SBPs, and albumin are present in multiple forms, possibly arising due to proteolysis or PTMs. The above functional categories suggest specific mechanisms and pathways for age‐related kidney degeneration. 相似文献
63.
The soluble expression of heterologous proteins in Escherichia coli remains a serious bottleneck in protein production. Although alteration of expression conditions can sometimes solve the problem, the best available tools to date have been fusion tags that enhance the solubility of expressed proteins. However, a systematic analysis of the utility of these solubility fusions has been difficult, and it appears that many proteins react differently to the presence of different solubility tags. The advent of high-throughput structural genomics programs and advances in cloning and expression technology afford us a new way to compare the effectiveness of solubility tags. This data should allow us to better predict the effectiveness of tags currently in use, and might also provide the information needed to identify new fusion tags. 相似文献
64.
Ankita Deb Bhavana Deshmukh Pranay Ramteke Firoz Khan Bhati Manoj Kumar Bhat 《Translational oncology》2021,14(10)
Resistin, a small secretory molecule, has been implicated to play an important role in the development of insulin resistance under obese condition. For the past few decades, it has been linked to various cellular and metabolic functions. It has been associated with diseases like metabolic disorders, cardiovascular diseases and cancers. Numerous clinical studies have indicated an increased serum resistin level in pathological disorders which have been reported to increase mortality rate in comparison to low resistin expressing subjects. Various molecular studies suggest resistin plays a pivotal role in proliferation, metastasis, angiogenesis, inflammation as well as in regulating metabolism in cancer cells. Therefore, understanding the role of resistin and elucidating its’ associated molecular mechanism will give a better insight into the management of these disorders. In this article, we summarize the diverse roles of resistin in pathological disorders based on the available literature, clinicopathological data, and a compiled study from various databases. The article mainly provides comprehensive information of its role as a target in different treatment modalities in pre as well as post-clinical studies. 相似文献
65.
Thymol, a naturally occurring phenolic compound, has been known for its antioxidant, anti microbial, and anti inflammatory activity. Thymol has also been reported as anti-cancer agent, but its anti-cancer mechanism has not yet been fully elucidated. Thus, we aimed to investigate anticancer activity of thymol on HL-60 (acute promyelotic leukemia) cells. In our study, thymol demonstrated dose dependent cytotoxic effects on HL-60 cells after 24 h of exposure. However, thymol did not show any cytotoxic effect in normal human PBMC. The cytotoxic effect of thymol on HL-60 cells appears to be associated with induction of cell cycle arrest at sub G0/G1 phase, and apoptotic cell death based on genomic DNA fragmentation pattern. Thymol also showed significant increase in production of reactive oxygen species (ROS) activity, increase in mitochondrial H2O2 production and depolarization of mitochondrial membrane potential. On performing Western Blot analysis, thymol showed increase in Bax protein level with a concomitant decrease in Bcl2 protein expression in a dose dependent manner. Our study also showed activation of caspase -9, -8 and -3 and concomitant PARP cleavage, which is the hallmark of caspase-dependent apoptosis. Moreover, to rule out the involvement of other mechanisms in apoptosis induction by thymol, we also studied its effect on apoptosis inducing factor (AIF). Thymol induced AIF translocation from mitochondria to cytosol and to nucleus, thus indicating its ability to induce caspase independent apoptosis. We conclude that, thymol-induced apoptosis in HL-60 cells involves both caspase dependent and caspase independent pathways. 相似文献
66.
67.
Valeria N. Debárbora Atilio J. Mangold Ayelén Eberhardt Alberto A. Guglielmone Santiago Nava 《Experimental & applied acarology》2014,63(2):285-294
Natural infestation of Amblyomma dubitatum in relation to individual specific attributes of Hydrochoerus hydrochaeris such as sex, body mass and body condition was analyzed. The anatomical distribution of A. dubitatum on H. hyrochaeris was also evaluated. Prevalence of adults and nymphs were significantly higher than prevalence of larvae. Non-significant differences in the infestation levels were found among host sex. Multiple regression analysis did not show any statistically significant association among the level of infestation with ticks and body mass and body condition of the host. All parasitic tick stages were collected in all five anatomical areas of the host, but they exhibited significant differences in feeding site preference. Factors associated to the host which determine the high levels of infestation with A. dubitatum could be assigned to a combination of population-level properties of the host as abundance, ubiquity and aggregation, rather than individual specific attributes related to body condition, body mass or sex. 相似文献
68.
Marco O. Bertelli Luis Salvador‐Carulla Daniela Scuticchio Niccolò Varrucciu Rafael Martinez‐Leal Sally‐Ann Cooper Rune J. Simeonsson Shoumitro Deb Germain Weber Rex Jung Kerim Munir Colleen Adnams Leyla Akoury‐Dirani Satish Chandra Girimaji Gregorio Katz Henry Kwok Carolyn Walsh 《World psychiatry》2014,13(1):93-94
69.
Katharigatta N. Venugopala Sandeep Chandrashekharappa Pran Kishore Deb Christophe Tratrat Melendhran Pillay Deepak Chopra Nizar A. Al-Shari Wafa Hourani Lina A. Dahabiyeh Pobitra Borah Rahul D. Nagdeve Susanta K. Nayak Basavaraj Padmashali Mohamed A. Morsy Bandar E. Aldhubiab Mahesh Attimarad Anroop B. Nair Nagaraja Sreeharsha Michelyne Haroun Sheena Shashikanth Viresh Mohanlall Raghuprasad Mailavaram 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):1472
A series of 1,2,3-trisubstituted indolizines (2a–2f, 3a–3d, and 4a–4c) were screened for in vitro whole-cell anti-tubercular activity against the susceptible H37Rv and multidrug-resistant (MDR) Mycobacterium tuberculosis (MTB) strains. Compounds 2b–2d, 3a–3d, and 4a–4c were active against the H37Rv-MTB strain with minimum inhibitory concentration (MIC) ranging from 4 to 32 µg/mL, whereas the indolizines 4a–4c, with ethyl ester group at the 4-position of the benzoyl ring also exhibited anti-MDR-MTB activity (MIC = 16–64 µg/mL). In silico docking study revealed the enoyl-acyl carrier protein reductase (InhA) and anthranilate phosphoribosyltransferase as potential molecular targets for the indolizines. The X-ray diffraction analysis of the compound 4b was also carried out. Further, a safety study (in silico and in vitro) demonstrated no toxicity for these compounds. Thus, the indolizines warrant further development and may represent a novel promising class of InhA inhibitors and multi-targeting agents to combat drug-sensitive and drug-resistant MTB strains. 相似文献
70.
Ian P. Adams Anna Skelton Roy Macarthur Tobias Hodges Howard Hinds Laura Flint Palash Deb Nath Neil Boonham Adrian Fox 《PloS one》2014,9(11)
Internal necrosis of carrot has been observed in UK carrots for at least 10 years, and has been anecdotally linked to virus infection. In the 2009 growing season some growers had up to 10% of yield with these symptoms. Traditional diagnostic methods are targeted towards specific pathogens. By using a metagenomic approach with high throughput sequencing technology, other, as yet unidentified causes of root necrosis were investigated. Additionally a statistical analysis has shown which viruses are most closely associated with disease symptoms. Carrot samples were collected from a crop exhibiting root necrosis (102 Affected: 99 Unaffected) and tested for the presence of the established carrot viruses: Carrot red leaf virus (CtRLV), Carrot mottle virus (CMoV), Carrot red leaf associated viral RNA (CtRLVaRNA) and Parsnip yellow fleck virus (PYFV). The presence of these viruses was not associated with symptomatic carrot roots either as single viruses or in combinations. A sub-sample of carrots of mixed symptom status was subjected to MiSeq sequencing. The results from these tests suggested Carrot yellow leaf virus (CYLV) was associated with symptomatic roots. Additionally a novel Torradovirus, a novel Closterovirus and two novel Betaflexiviradae related plant viruses were detected. A specific diagnostic test was designed for CYLV. Of the 102 affected carrots, 98% were positive for CYLV compared to 22% of the unaffected carrots. From these data we conclude that although we have yet to practically demonstrate a causal link, CYLV appears to be strongly associated with the presence of necrosis of carrots. 相似文献