全文获取类型
收费全文 | 399篇 |
免费 | 30篇 |
国内免费 | 1篇 |
出版年
2021年 | 6篇 |
2020年 | 2篇 |
2019年 | 9篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 11篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 22篇 |
2012年 | 26篇 |
2011年 | 24篇 |
2010年 | 13篇 |
2009年 | 11篇 |
2008年 | 22篇 |
2007年 | 14篇 |
2006年 | 16篇 |
2005年 | 15篇 |
2004年 | 17篇 |
2003年 | 9篇 |
2002年 | 9篇 |
2001年 | 9篇 |
2000年 | 12篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 5篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 12篇 |
1991年 | 10篇 |
1990年 | 9篇 |
1989年 | 9篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 6篇 |
1982年 | 6篇 |
1980年 | 3篇 |
1979年 | 5篇 |
1978年 | 5篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1974年 | 5篇 |
1973年 | 4篇 |
1971年 | 3篇 |
1970年 | 4篇 |
1969年 | 1篇 |
1967年 | 3篇 |
排序方式: 共有430条查询结果,搜索用时 15 毫秒
381.
A Berti M Stefani G Camici G Manao G Cappugi D Degl'Innocenti G Ramponi 《International journal of peptide and protein research》1986,28(1):15-21
Modifications in the muscle acylphosphatase purification procedure enabled us to isolate the enzyme with its sole cysteine in the -SH form; this enzyme form is the most abundant in vivo. Our data demonstrates that the enzyme forms purified by previously reported procedures can be easily derived from a reaction of the SH-enzyme with oxidized glutathione. Probably most, or even all, of these enzyme forms are artifacts due to the purification. The SH-acylphosphatase shows kinetic parameters similar to those reported for the mixed disulfide with glutathione and S-S dimer, except for the specific activity value, which is about twice as much, and the Km, which is reduced. 相似文献
382.
Bruna Muller Cardoso Tatiane Fran?a Perles de Mello Sara Negr?o Lopes Izabel Galhardo Demarchi Daniele Stefani Lopes Lera Raíssa Bocchi Pedroso Diogenes Aparício Cortez Zilda Cristiani Gazim Sandra Mara Alessi Aristides Thais Gomes Verzignassi Silveira Maria Valdrinez Campana Lonardoni 《Memórias do Instituto Oswaldo Cruz》2015,110(8):1024-1034
The herbaceous shrub Tetradenia riparia has been traditionally used
to treat inflammatory and infectious diseases. Recently, a study showed that
T. riparia essential oil (TrEO) obtained in summer has
antileishmanial effects, although these results could be influenced by seasonal
variation. This study evaluated the activity of the TrEO obtained in different
seasons against Leishmania (Leishmania) amazonensis, in vitro and in
vivo. The compounds in the TrEO were analysed by gas chromatography-mass
spectrometry; terpenoids were present and oxygenated sesquiterpenes were the majority
compounds (55.28%). The cytotoxicity and nitric oxide (NO) production were also
tested after TrEO treatment. The TrEO from all seasons showed a 50% growth inhibitory
concentration for promastigotes of about 15 ng/mL; at 30 ng/mL and 3 ng/mL, the TrEO
reduced intracellular amastigote infection, independently of season. The TrEO from
plants harvested in summer had the highest 50% cytotoxic concentration, 1,476 ng/mL
for J774.A1 macrophages, and in spring (90.94 ng/mL) for murine macrophages. NO
production did not change in samples of the TrEO from different seasons. The
antileishmanial effect in vivo consisted of a reduction of the parasite load in the
spleen. These results suggest that the TrEO has potential effects on L. (L.)
amazonensis, consonant with its traditional use to treat parasitic
diseases. 相似文献
383.
Clarissa Hamaio Okino-Delgado Milene Stefani Pereira João Vitor Inácio da Silva Daniela Kharfan Débora Zanoni do Prado Luciana Francisco Fleuri 《Biotechnology progress》2019,35(1):e2734
Brazil is the world's leading orange supplier for juice production purposes. However, the production process generates high amount of wastes, which leads to disposal problems. Orange wastes can be used for lipases production, incorporating the biorefinery concept into juice industries. Thus, the aim of the present study was to investigate the wastes of orange production chain as source of lipases based on different varieties (Pera, Hamlin, Valencia, and Natal), as well as on different fractions of wastes. The mass balance of the juice/wastes (2007–2016 crops) was evaluated, and lipases from different varieties and fraction were biochemically characterized. Overall, the wastes corresponded to approximately 43% of the fruit mass. All the fractions of all varieties showed lipase activity in emulsified olive oil and in p-nitrophenyl substrates. The highest lipase activities were obtained by Natal pulp in emulsified olive oil, Natal frit, and Hamlin peel in p-NPB and Hamlin frit in p-NPL and p-NPP. The bagasse, peel, and frit lipases from the different orange varieties showed optimum pH from 6.0 to 8.0 and optimal temperature from 30 °C to 60 °C. Thus, it is possible concluding that the orange processing for juice production purposes generates a large amount of wastes, which can be destined to profitable purposes as lipases production. Lipases produced by different fractions and varieties are biochemically diverse, enabling the application a wide range of processes. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2734, 2019 相似文献
384.
385.
386.
Matheus D. Baldissera Carine F. Souza Pedro H. Doleski Daniela B. R. Leal Lenita M. Stefani Aline A. Boligon Silvia G. Monteiro 《Molecular and cellular biochemistry》2017,430(1-2):127-137
In waterfowls, overfeeding leads to a hepatic steatosis, also called “foie gras.” We decided to investigate the role of glucose metabolism in steatosis emergence. For this, we measured the expression of genes during the 12 h following the last meal of the overfeeding period. As expected, it showed that the expression of glucose transporter is more precocious in jejunal mucosa, especially for SGLT1, known to be the major transporter at the apical surface. In the liver, GLUT2 and HK1 are upregulated at the same time and seem to work together to import glucose. In peripherals tissues, such as muscle and subcutaneous adipose tissue (SAT), expression of genes of interest occurs later than the one in jejunum and liver. These results are in accordance with the evolution of glycemia. This study allows us to better understand the kinetic treatment of glucose after a meal in overfed ducks. It also will allow researchers to better target their sampling time knowing the optimal point of expression of each gene. 相似文献
387.
388.
R Stefani G P Serra F Loffredo S Spiga 《Archivio italiano di anatomia e di embriologia》1990,95(1):27-43
The epithelial bell which surrounds the clitoris in most mammals arises by fusion of visceral and parietal layers of the prepuce. Adhesion of the epithelia occurs between the squamous cells and a normal connection is formed by desmosomes and other junctions. There is total absence of cornifications. The squamous epithelial double lamina splits occasionally in some patches where the free surfaces are getting back to a normal process of keratinization as in the wall of the vestibule. In the closed pits the keratin scales form squamous granules without sebaceous secretion. Sometimes a similar process occurs in the human prepuce with the same results as described in cat and rabbit. The granules of keratin are different from the smegmaliths as they do not contain sebaceous secretion. 相似文献
389.
M Stefani G Camici G Manao G Cappugi G Liguri D Degl'Innocenti N Landi A Berti 《The Italian journal of biochemistry》1985,34(2):94-108
The use of an affinity chromatography step performed with an immunoadsorbent consisting of anti-horse muscle acylphosphatase antibodies covalently linked to Sepharose 4B allowed us to purify horse heart acylphosphatase in a very rapid and efficient fashion. As in skeletal muscle, also in heart the enzyme is present as both a mixed disulfide with glutathione and a S-S dimer. The abundance of these forms in heart is quite lower than in skeletal muscle. The comparison of the molecular forms so purified with those obtained from horse skeletal muscle showed the same aminoacid composition, tryptic fingerprint, together with strictly similar apparent molecular weight and main kinetic parameters, supporting the conclusion that the acylphosphatase present in heart is the same enzyme as that purified from skeletal muscle. 相似文献
390.