全文获取类型
收费全文 | 162篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
168篇 |
出版年
2015年 | 3篇 |
2014年 | 5篇 |
2013年 | 3篇 |
2012年 | 3篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2009年 | 3篇 |
2008年 | 4篇 |
2007年 | 7篇 |
2006年 | 5篇 |
2004年 | 3篇 |
1999年 | 1篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 6篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1972年 | 3篇 |
1971年 | 3篇 |
1969年 | 1篇 |
1959年 | 1篇 |
1958年 | 8篇 |
1957年 | 8篇 |
1956年 | 7篇 |
1955年 | 13篇 |
1954年 | 5篇 |
1953年 | 10篇 |
1952年 | 2篇 |
1951年 | 4篇 |
1950年 | 4篇 |
1949年 | 2篇 |
1948年 | 1篇 |
1947年 | 1篇 |
1934年 | 1篇 |
排序方式: 共有168条查询结果,搜索用时 0 毫秒
91.
92.
93.
94.
BERG P 《The Journal of biological chemistry》1956,222(2):1025-1034
95.
96.
97.
Yescas CP MA Segura C L Martínez C VP Álvarez R JA Montemayor T JA Orozco V JE Frías R 《Phyton》2015,84(2):272-279
The scarcity of water in arid and semiarid regions of the world is a problem that every day increases by climate change. The subsurface drip irrigation (SDI) and changes in population density of plants are alternatives that can be used to make a sustainable use of water. Therefore, the objectives of this study were to determine the combination that allows for an increased corn performance and efficient use of water without losing the quality of forage. Three different irrigation levels were applied through a system of a SDI at three different densities of forage maize plants in an arid region. The results demonstrated that by applying different levels of water, either enough or lack of soil moisture is created, which is directly reflected in crop yield, and its determining variables such as green forage and dry matter yield, and nutritional quality. The irrigation level to a 100% of potential evapotranspiration (PET), at a density of 80000 plants/ha, increased yield of green forage to 57664 kg/ha; crude protein was 8.59%, while the rest of the quality parameters decreased. This study allowed to conclude that the irrigation level was the major factor in the response of the crop. 相似文献
98.
Sebastian Anusha Baburajeev CP Chakrabhavi Dhananjaya Mohan Jessin Mathai Shobith Rangappa Surender Mohan Chandra Shardul Paricharak Lewis Mervin Julian E. Fuchs Mahedra M Andreas Bender Basappa Kanchugarakoppal S. Rangappa 《PloS one》2015,10(10)
In this work, we describe the ‘green’ synthesis of novel 6-(adamantan-1-yl)-2-substituted-imidazo[2,1-b][1,3,4]thiadiazoles (AITs) by ring formation reactions using 1-(adamantan-1-yl)-2-bromoethanone and 5-alkyl/aryl-2-amino1,3,4-thiadiazoles on a nano material base in ionic liquid media. Given the established activity of imidazothiadiazoles against M. tuberculosis, we next examined the anti-TB activity of AITs against the H37Rv strain using Alamar blue assay. Among the tested compounds 6-(adamantan-1-yl)-2-(4-methoxyphenyl)imidazo[2,1-b][1,3,4]thiadiazole (3f) showed potent inhibitory activity towards M. tuberculosis with an MIC value of 8.5 μM. The inhibitory effect of this molecule against M. tuberculosis was comparable to the standard drugs such as Pyrazinamide, Streptomycin, and Ciprofloxacin drugs. Mechanistically, an in silico analysis predicted sterol 14α-demethylase (CYP51) as the likely target and experimental activity of 3f in this system corroborated the in silico target prediction. In summary, we herein report the synthesis and biological evaluation of novel AITs against M. tuberculosis that likely target CYP51 to induce their antimycobacterial activity. 相似文献
99.
Studies on the binding site of the galactose-specific agglutinin PA-IL from Pseudomonas aeruginosa 总被引:1,自引:0,他引:1
The binding properties of Pseudomonas aeruginosa agglutinin-I (PA-IL) with
glycoproteins (gps) and polysaccharides were studied by both the
biotin/avidin-mediated microtiter plate lectin-binding assay and the
inhibition of agglutinin-glycan interaction with sugar ligands. Among 36
glycans tested for binding, PA-IL reacted best with two glycoproteins
containing Galalpha1-->4Gal determinants and a human blood group ABO
precursor equivalent gp, but this lectin reacted weakly or not at all with
A and H active gps or sialylated gps. Among the mammalian disaccharides
tested by the inhibition assay, the human blood group Pkactive
Galalpha1-->4Gal, was the best. It was 7.4-fold less active than
melibiose (Galalpha1-->6Glc). PA-IL has a preference for the
alpha-anomer in decreasing order as follows: Galalpha1-->6
>Galalpha1-->4 >Galalpha1-->3. Of the monosaccharides studied,
the phenylbeta derivatives of Gal were much better inhibitors than the
methylbeta derivative, while only an insignificant difference was found
between the Galalpha anomer of methyl- and p -NO2-phenyl derivatives. From
these results, it can be concluded that the combining size of the
agglutinin is as large as a disaccharide of the alpha-anomer of Gal at
nonreducing end and most complementary to Galalpha1-->6Glc. As for the
combining site of PA-IL toward the beta-anomer, the size is assumed to be
less than that of Gal; carbon-6 in the pyranose form is essential, and
hydrophobic interaction is important for binding.
相似文献
100.