全文获取类型
收费全文 | 113篇 |
免费 | 6篇 |
出版年
2019年 | 1篇 |
2015年 | 2篇 |
2014年 | 2篇 |
2013年 | 5篇 |
2012年 | 8篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 7篇 |
2007年 | 8篇 |
2006年 | 8篇 |
2005年 | 4篇 |
2004年 | 5篇 |
2003年 | 4篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1961年 | 1篇 |
1959年 | 1篇 |
1948年 | 2篇 |
1941年 | 1篇 |
1939年 | 1篇 |
1937年 | 1篇 |
1936年 | 1篇 |
1930年 | 1篇 |
排序方式: 共有119条查询结果,搜索用时 15 毫秒
111.
112.
113.
Gene induction during differentiation of human monocytes into dendritic cells: an integrated study at the RNA and protein levels 总被引:2,自引:0,他引:2
Catherine Angénieux Dominique Fricker Jean-Marc Strub Sylvie Luche Huguette Bausinger Jean-Pierre Cazenave Alain Dorsselaer Daniel Hanau Henri de la Salle Thierry Rabilloud 《Functional & integrative genomics》2001,1(5):323-329
Changes in gene expression occurring during differentiation of human monocytes into dendritic cells were studied at the RNA and protein levels. These studies showed the induction of several gene classes corresponding to various biological functions. These functions encompass antigen processing and presentation, cytoskeleton, cell signalling and signal transduction, but also an increase in mitochondrial function and in the protein synthesis machinery, including some, but not all, chaperones. These changes put in perspective the events occurring during this differentiation process. On a more technical point, it appears that the studies carried out at the RNA and protein levels are highly complementary. 相似文献
114.
115.
A "lactase solution" was prepared from Escherichia coli. The mechanism of its action has been studied and changes in the rate of hydrolysis under various conditions investigated. The hydrolysis of lactose by the enzyme approximates the course of reaction of the integrated Michaelis-Menten equation. One molecule of enzyme combines with one molecule of substrate. E. coli lactase is readily inactivated at pH 5.0, and its optimal activity at 36°C. is reached between pH 7.0 and pH 7.5. The optimal temperature for its action was found to be 46°C. when determinations were carried out after an incubation period of 30 minutes. Its inactivation by heat follows the course of a first order reaction, and the critical thermal increment between the temperatures of 45°C. and 53°C. was calculated to be 56,400 calories per mol. The enzyme is activated by potassium cyanide, sodium sulfide, and cysteine, and irreversibly inactivated by mercuric chloride, silver nitrate, and iodine. After inactivation with copper sulfate partial reactivation is possible, while the slight inhibition brought about by hydrogen peroxide is completely reversible. The possible structure of the active groups of E. coli lactase as compared with other enzymes has been discussed. 相似文献
116.
117.
Sophie La Salle Christopher C Oakes Oana R Neaga Déborah Bourc'his Timothy H Bestor Jacquetta M Trasler 《BMC developmental biology》2007,7(1):104
Background
Formation of haploid spermatozoa capable of fertilization requires proper programming of epigenetic information. Exactly how DNMT3L (DNA methyltransferase 3-Like), a postulated regulator of DNA methyltransferase activity, contributes to DNA methylation pattern acquisition during gametogenesis remains unclear. Here we report on the role of DNMT3L in male germ cell development. 相似文献118.
Aromatase inhibition and experimental antitumor activity of FCE 24304, MDL 18962 and SH 489 总被引:2,自引:0,他引:2
E di Salle G Briatico D Giudici G Ornati T Zaccheo 《Journal of steroid biochemistry》1989,34(1-6):431-434
Human placental aromatase inhibitory properties of FCE 24304, MDL 18962, SH 489 and 4-hydroxyandrostenedione (4-OHA) were compared. The compounds caused time-dependent enzyme inactivation with t1/2 values of 13.9, 13.1, 45.3 and 2.1 min and Ki values of 26.0, 0.7, 2.0 and 29.0 nM respectively. The antitumor activity of FCE 24304, MDL 18962 and SH 489 was studied on the DMBA-induced mammary tumor in rats, at daily s.c. doses of 10 and 50 mg/kg. FCE 24304 induced 30 and 73% regressions of established tumors, associated with 86 and 93% decrease in total ovarian aromatase activity. SH 489 and MDL 18962 did not affect tumor growth. FCE 24304, like 4-OHA, was shown to inhibit LH hypersection in castrated rats. A gonadotropin suppressive effect could contribute to the antitumor activity of aromatase inhibitors in intact DMBA-induced tumor bearing rats. 相似文献
119.
Oxygen consumption (VO2) and carbon dioxide emission (VCO2) have been continuously recorded for 24 consecutive hours in 7 premature infants with a range of gestational age of 29-31 weeks at birth, and placed in incubators within a thermal neutral limit. These infants, submitted to continuous light, were fed every 3-4h through a gastric tube which was left in their stomachs throughout the whole experiment. Variance and spectral analyses performed on VCO2 values sampled on the recordings every 10 min showed ultradian variations, in the 40 min-6 h period range, which represent 20 and even 40% of the mean level. Moreover 5 out of the 7 premature infants show ultradian VCO2, VO2 and respiratory quotient rhythms related to feeding frequency. 相似文献