全文获取类型
收费全文 | 214篇 |
免费 | 12篇 |
专业分类
226篇 |
出版年
2022年 | 2篇 |
2021年 | 6篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 4篇 |
2015年 | 6篇 |
2014年 | 6篇 |
2013年 | 9篇 |
2012年 | 18篇 |
2011年 | 11篇 |
2010年 | 11篇 |
2009年 | 4篇 |
2008年 | 10篇 |
2007年 | 14篇 |
2006年 | 9篇 |
2005年 | 7篇 |
2004年 | 2篇 |
2003年 | 6篇 |
2002年 | 7篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 6篇 |
1996年 | 2篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1979年 | 2篇 |
1977年 | 2篇 |
1973年 | 3篇 |
1972年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1968年 | 3篇 |
1967年 | 4篇 |
1966年 | 2篇 |
1960年 | 1篇 |
1958年 | 1篇 |
1956年 | 1篇 |
1954年 | 1篇 |
1946年 | 1篇 |
排序方式: 共有226条查询结果,搜索用时 0 毫秒
91.
S ummary . The antigenic patterns of the crystal protein inclusions of Bacillus thuringiensis were determined. No specific antigenic patterns associated with previously described subgroups of this species were found. A larger number of categories of crystal antigen than of flagellar antigen or esterase type were found. In some cases isolates indistinguishable in classifications based on flagellar antigens or esterase types could be subdivided by their crystal antigenic pattern. The use of crystal antigens in classification is discussed. 相似文献
92.
93.
Michael W. Pendleton Dorothy K. Washburn E. Ann Ellis Bonnie B. Pendleton 《The Yale journal of biology and medicine》2014,87(1):15-20
The same sherd was analyzed using a scanning electron microscope with energy dispersive spectroscopy (SEM-EDS) and a micro X-ray fluorescence tube attached to a scanning electron microscope (Micro-XRF-SEM) to compare the effectiveness of elemental detection of iron-based pigment. To enhance SEM-EDS mapping, the sherd was carbon coated. The carbon coating was not required to produce Micro-XRF-SEM maps but was applied to maintain an unbiased comparison between the systems. The Micro-XRF-SEM analysis was capable of lower limits of detection than that of the SEM-EDS system, and therefore the Micro-XRF-SEM system could produce elemental maps of elements not easily detected by SEM-EDS mapping systems. Because SEM-EDS and Micro-XRF-SEM have been used for imaging and chemical analysis of biological samples, this comparison of the detection systems should be useful to biologists, especially those involved in bone or tooth (hard tissue) analysis. 相似文献
94.
André M Siqueira Lucas I Coutinho Rafael L Gurgel Willian CS Su Luiz M Carvalho Silvana G Benzecry Aline CC Alencar Márcia AA Alexandre Maria Gra?as C Alecrim Marcus VG Lacerda 《Memórias do Instituto Oswaldo Cruz》2014,109(5):540-545
Plasmodium vivax is the most widespread parasite causing malaria, being
especially prevalent in the Americas and Southeast Asia. Children are one of the
most affected populations, especially in highly endemic areas. However, there are
few studies evaluating the therapeutic response of infants with vivax malaria.
This study retrospectively evaluated the parasitaemia clearance in children
diagnosed with vivax malaria during the first five days of exclusive treatment
with chloroquine (CQ). Infants aged less than six months old had a significantly
slower parasitaemia clearance time compared to the group of infants and children
between six months and 12 years old (Kaplan-Meier survival analysis; Wilcoxon
test; p = 0.004). The impaired clearance of parasitaemia in younger children with
vivax malaria is shown for the first time in Latin America. It is speculated that
CQ pharmacokinetics in young children with vivax malaria is distinct, but this
specific population may also allow the detection of CQ-resistant parasites during
follow-up, due to the lack of previous immunity. 相似文献
95.
Zhande R Zhang W Zheng Y Pendleton E Li Y Polakiewicz RD Sun XJ 《The Journal of biological chemistry》2006,281(51):39071-39080
Protein phosphorylation is an important mechanism that controls many cellular activities. Phosphorylation of a given protein is precisely controlled by two opposing biochemical reactions catalyzed by protein kinases and protein phosphatases. How these two opposing processes are coordinated to achieve regulation of protein phosphorylation is unresolved. We have developed a novel experimental approach to directly study protein dephosphorylation in cells. We determined the kinetics of dephosphorylation of insulin receptor substrate-1/2, Akt, and ERK1/2, phosphoproteins involved in insulin receptor signaling. We found that insulin-induced ERK1/2 and Akt kinase activities were completely abolished 10 min after inhibition of the corresponding upstream kinases with PD98059 and LY294002, respectively. In parallel experiments, insulin-induced phosphorylation of Akt, ERK1/2, and insulin receptor substrate-1/2 was decreased and followed similar kinetics. Our findings suggest that these proteins are dephosphorylated by a default mechanism, presumably via constitutively active phosphatases. However, dephosphorylation of these proteins is overcome by activation of protein kinases following stimulation of the insulin receptor. We propose that, during acute insulin stimulation, the kinetics of protein phosphorylation is determined by the interplay between upstream kinase activity and dephosphorylation by default. 相似文献
96.
97.
Haines RJ Corbin KD Pendleton LC Eichler DC 《The Journal of biological chemistry》2012,287(31):26168-26176
98.
We estimated trends in abundance of harbor seals ( Phoca vitulina richardsii ) using over dispersed, multinomial models and counts obtained during aerial surveys conducted during 1983–2001 in the Ketchikan, Sitka, Kodiak, and Bristol Bay areas of Alaska. Harbor seal numbers increased significantly at 7.4%/yr during 1983–1998 and 5.6%/yr during 1994–1998 in the Ketchikan area, and 6.6%/yr during 1993–2001 in the Kodiak area. Counts were stable (trends not significant) during 1984–2001 (0.7%/yr) and 1995–2001 (-0.4%/yr) in Sitka, and during 1998–2001 (-1.3%/yr) in Bristol Bay. The influence of covariates ( e.g. , survey date, tide height) on trend estimates was significant and varied among areas and across years, demonstrating the need to include covariates in statistical analyses to accurately estimate trend. Our increasing trend estimate for Kodiak represents the first documented increase in harbor seal numbers over a relatively expansive area in the Gulf of Alaska. However, the trend for the Gulf of Alaska stock is equivocal due to the continued decline in Prince William Sound. Similarly, the trend for the Southeast Alaska stock is equivocal based on our increasing (Ketchikan) and stable (Sitka) trend estimates, and a recent decline reported for Glacier Bay. The Bering Sea stock appears stable after a period of possible decline. 相似文献
99.
100.
Roshandel D Thomson W Pye SR Boonen S Borghs H Vanderschueren D Huhtaniemi IT Adams JE Ward KA Bartfai G Casanueva FF Finn JD Forti G Giwercman A Han TS Kula K Lean ME Pendleton N Punab M Wu FC Holliday KL O'Neill TW;EMAS Study Group 《PloS one》2011,6(11):e28031