全文获取类型
收费全文 | 1442篇 |
免费 | 67篇 |
国内免费 | 1篇 |
出版年
2023年 | 5篇 |
2022年 | 4篇 |
2021年 | 18篇 |
2020年 | 13篇 |
2019年 | 22篇 |
2018年 | 24篇 |
2017年 | 13篇 |
2016年 | 41篇 |
2015年 | 58篇 |
2014年 | 64篇 |
2013年 | 96篇 |
2012年 | 123篇 |
2011年 | 89篇 |
2010年 | 62篇 |
2009年 | 47篇 |
2008年 | 113篇 |
2007年 | 97篇 |
2006年 | 68篇 |
2005年 | 80篇 |
2004年 | 80篇 |
2003年 | 79篇 |
2002年 | 88篇 |
2001年 | 11篇 |
2000年 | 9篇 |
1999年 | 10篇 |
1998年 | 13篇 |
1997年 | 14篇 |
1996年 | 15篇 |
1995年 | 8篇 |
1994年 | 12篇 |
1993年 | 7篇 |
1992年 | 8篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1984年 | 10篇 |
1983年 | 13篇 |
1982年 | 10篇 |
1981年 | 12篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1976年 | 3篇 |
1975年 | 5篇 |
1974年 | 3篇 |
排序方式: 共有1510条查询结果,搜索用时 15 毫秒
991.
Uchida H Kawai Y Kinoshita H Kitazawa H Miura K Shiiba K Horii A Kimura K Taketomo N Oda M Yajima T Saito T 《Bioscience, biotechnology, and biochemistry》2006,70(12):3073-3076
Twenty lactobacilli isolated from human feces were studied for binding to the human blood type B-antigen [Galalpha1-3 (Fucalpha1-2) Gal-] and H-antigen (Fucalpha1-2Gal-] expressed sugar chains in human intestinal mucosa. We found two strains, L. gasseri OLL2755 and L. gasseri OLL2877 that firmly adhere to human B-antigen, and we found L. gasseri OLL2827 bound to the H-antigen. 相似文献
992.
Kojima N Sugino M Mikami A Nonaka K Fujinawa Y Muto I Matsubara K Ohtsuka E Komatsu Y 《Bioorganic & medicinal chemistry letters》2006,16(19):5118-5121
We developed novel amino-modifying reagents, of which an amino group was connected with an aromatic residue by aliphatic linker. It was proved that the insertion of the aromatic residue could increase the reactivity of the amino group on oligonucleotides in comparison with conventional amino-modification. 相似文献
993.
Hirata K Muraoka S Suenaga K Kuroda T Kato K Tanaka H Yamamoto M Takata M Yamada K Kigoshi H 《Journal of molecular biology》2006,356(4):945-954
Aplyronine A, isolated from the sea hare Aplysia kurodai, possesses an exceedingly potent antitumor effect in vivo and it is one of the promising candidates as an anticancer drug. This macrolide is known to depolymerize F-actin and inhibit the polymerization of actin by forming a 1:1 complex with monomeric actin. The first complex structure of actin-aplyronine A was determined via a synchrotron X-ray analysis at a 1.45 A resolution. As expected, aplyronine A binds to a hydrophobic cleft composed of subdomains 1 and 3 of actin by intercalating its aliphatic tail part into the actin molecule as do the other reported F-actin depolymerizing agents. Unexpectedly, this complex structure shows the specific structural features around the trimethylserine moiety, revealed as an important moiety of aplyronine A for cytotoxicity against HeLa cells. Combining this result and our previous one, the moiety should strongly relate to the specific biological activity of aplyronine A; i.e. a potent antitumor effect. 相似文献
994.
995.
Complete genome sequence of the dehalorespiring bacterium Desulfitobacterium hafniense Y51 and comparison with Dehalococcoides ethenogenes 195
下载免费PDF全文
![点击此处可从《Journal of bacteriology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Nonaka H Keresztes G Shinoda Y Ikenaga Y Abe M Naito K Inatomi K Furukawa K Inui M Yukawa H 《Journal of bacteriology》2006,188(6):2262-2274
Desulfitobacterium strains have the ability to dechlorinate halogenated compounds under anaerobic conditions by dehalorespiration. The complete genome of the tetrachloroethene (PCE)-dechlorinating strain Desulfitobacterium hafniense Y51 is a 5,727,534-bp circular chromosome harboring 5,060 predicted protein coding sequences. This genome contains only two reductive dehalogenase genes, a lower number than reported in most other dehalorespiring strains. More than 50 members of the dimethyl sulfoxide reductase superfamily and 30 paralogs of the flavoprotein subunit of the fumarate reductase are encoded as well. A remarkable feature of the genome is the large number of O-demethylase paralogs, which allow utilization of lignin-derived phenyl methyl ethers as electron donors. The large genome reveals a more versatile microorganism that can utilize a larger set of specialized electron donors and acceptors than previously thought. This is in sharp contrast to the PCE-dechlorinating strain Dehalococcoides ethenogenes 195, which has a relatively small genome with a narrow metabolic repertoire. A genomic comparison of these two very different strains allowed us to narrow down the potential candidates implicated in the dechlorination process. Our results provide further impetus to the use of desulfitobacteria as tools for bioremediation. 相似文献
996.
997.
Hashimoto I Wada J Hida A Baba M Miyatake N Eguchi J Shikata K Makino H 《Obesity (Silver Spring, Md.)》2006,14(5):799-811
Objective: Chronic inflammation observed in obesity has been reported to be implicated in the development of atherosclerosis. We screened candidate chemokines that link chronic inflammation and obesity. Research Methods and Procedures: Japanese overweight (n = 39, BMI 28.7 ± 0.65 kg/m2) and normal‐weight (n = 24, BMI 22.3 ± 0.45 kg/m2) subjects were enrolled. Using antibody‐based protein microarray, spot intensities of monocyte chemoattractant protein (MCP)‐4, eotaxin, and eotaxin‐2 correlated with anthropometric parameters. We further measured serum concentration of these chemokines and mRNA levels in adipose tissues obtained from volunteers. Results: Serum MCP‐4 levels showed positive correlation with BMI (r = 0.318, p = 0.014), waist (r = 0.316, p = 0.018), and waist‐to‐hip ratio (WHR) (r = 0.264, p = 0.049). Furthermore, MCP‐4 correlated with homeostasis model assessment of insulin resistance (r = 0.392, p = 0.002), high‐sensitivity C‐reactive protein (hsCRP) (r = 0.350, p = 0.006). In step‐wise multiple regression analyses, hsCRP independently correlated with MCP‐4 levels. The expression of MCP‐4 mRNA in visceral adipose tissue positively correlates with BMI. Serum eotaxin levels correlate with BMI (r = 0.262, p = 0.045) and WHR (r = 0.383, p = 0.003). Serum eotaxin‐2 levels correlated with BMI (r = 0.464, p < 0.001), waist (r = 0.333, p = 0.017), and WHR (r = 0.278, p = 0.048). However, eotaxin and eotaxin‐2 levels did not show significant correlation with hsCRP. Discussion: Serum levels of MCP‐4, eotaxin, and eotaxin‐2, which belong to CC chemokine family and share CC chemokine receptor 3, correlated with BMI. These chemokines, especially MCP‐4, may be critical molecules that link obesity and chronic inflammation. 相似文献
998.
Four species of 1SS-varinats of lysozyme were almost unstructured in water, judged from their near-UV CD and (1) H-(15) N-HSQC spectra. Some preferential structure might exist in such a disordered state, but the population of molecules in such a conformation must have been too small to be detected by spectroscopic methods. Indeed, our previous study showed that the addition of 30% glycerol induced the unstructured 2SS-variant of lysozyme to form a native-like structure. To extend this method to more disordered proteins, we attempted to detect some preferential structure latent in unstructured 1SS-variants by the glycerol-enhanced detection. Only in one molecular species of the four 1SS-variants, 1SS[6-127] containing a single disulfide bridge of Cys6-Cys127, a preferential structure was found in the presence of 50% glycerol. It was detected by near-UV CD measurements and the H/D exchange method combined with the NMR spectroscopy. The glycerol-induced structure in 1SS[6-127] was not localized only in the vicinity of Cys6-Cys127, and largely protected regions distributed themselves among A-, B-, and C-helices and Ile55 and Leu56. It was similar to the glycerol-induced structure in 2SS[6-127, 64-80] containing two disulfide bridges of Cys6-Cys127 and Cys64-Cys80, although the former was less rigid than the latter. The role of A-helix (residues 4-15) is proposed as an origin of excellent potential of Cys6-Cys127 for inducing a tertiary structure in the α-domain. 相似文献
999.
Cytokinin dehydrogenase (CKX) catalyzes the irreversible degradation of cytokinins (CKs). CKs play a role in the regulation of hydrogen peroxide (H(2)O(2)) accumulation while H(2)O(2) is involved in chlorophyll degradation. Here, we elucidated how CKX differentially regulates representative CK levels and indirectly influence H(2)O(2) accumulation in tomato leaves. We induced drought, salt and iron-deficiency stresses in tomato plants and found that chlorosis-inducing stresses (salt and iron-deficiency) induced lower chlorophyll levels as compared to drought stress and control. Protein gel blot analysis detected two CKXs in tomato leaves: a 35 kDa protein (CKX35) found in chlorotic leaves associated with a reduction in representative CK levels and high H(2)O(2) concentrations, and a 37 kDa protein (CKX37) found in green leaves associated with representative CKs and H(2)O(2) at normal levels. In summary, CKX isoforms in the tomato leaf appear to have distinct roles in differentially regulating CK levels and indirectly influencing H(2)O(2) accumulation. 相似文献
1000.
Masakazu Nagashima Hiroshi Takahashi Kenichi Shimane Yuichi Nagase Koichi Wauke 《Arthritis research & therapy》2012,14(5):R224