全文获取类型
收费全文 | 116篇 |
免费 | 7篇 |
出版年
2022年 | 3篇 |
2021年 | 7篇 |
2020年 | 1篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 3篇 |
2012年 | 8篇 |
2011年 | 4篇 |
2009年 | 4篇 |
2008年 | 1篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 8篇 |
1999年 | 6篇 |
1998年 | 10篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 4篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有123条查询结果,搜索用时 31 毫秒
1.
2.
Dahlia Minc-Golomb Gal Yadid Ilan Tsarfaty James H. Resau Joan P. Schwartz 《Journal of neurochemistry》1996,66(4):1504-1509
Abstract: In the CNS, nitric oxide (NO) functions as both neuromodulator and neurotoxic agent. In vivo neuronal expression of NO synthase (NOS) has been attributed to constitutive NOS—both the neuronal and the endothelial types. The other class of NOS—the inducible NOS (iNOS)—is known to mediate toxic effects of NO in various tissues. In this study, we show for the first time that direct intracerebellar injection of endotoxin and cytokine (lipopolysaccharide and interferon-γ) induced in vivo neuronal expression of the iNOS gene, as demonstrated by fluorescent in situ hybridization and immunohistochemical staining analyzed by confocal laser-scanning microscopy. This raises the possibility that neuronal iNOS might contribute significantly to the vulnerability of the brain to various insults. 相似文献
3.
Detecting non-neutral heterogeneity across a region of DNA sequence in the ratio of polymorphism to divergence 总被引:11,自引:4,他引:7
Natural selection, in the form of balancing selection or selective sweeps,
can result in a decoupling of the amounts of molecular polymorphism and
divergence. Thus natural selection can cause some areas of DNA sequence to
have greater silent polymorphism, relative to divergence between species,
than other areas. It would be useful to have a statistical test for
heterogeneity in the polymorphism to divergence ratio across a region of
DNA sequence, one that could identify heterogeneity greater than that
expected from the neutral processes of mutation, drift, and recombination.
The only currently available test requires that a region be arbitrarily
divided into sections that are compared with each other, and the
subjectivity of this division could be problematic. Here a test is proposed
in which runs of polymorphic and fixed sites are counted, where a "run" is
a set of one or more sites of one type preceded and followed by the other
type. The number of runs is smaller than otherwise expected if
polymorphisms are clumped together. By simulating neutral evolution and
comparing the observed number of runs to the simulations, a statistical
test is possible which does not require any a priori decisions about
subdivision.
相似文献
4.
James H. Resau Kosaku Sakamoto John R. Cottrell Eric A. Hudson Stephen J. Meltzer 《Cytotechnology》1991,7(3):137-149
Organ explant culture models offer several significant advantages for studies of patho-physiologic mechanisms like cell injury, secretion, differentiation and structure development. Organs or small explants/slices can be removed in vivo and maintained in vitro for extended periods of time if careful attention is paid to the media composition, substrate selection, and atmosphere. In the case of human tissues obtained from autopsy or surgery, additional attention must be paid to the postmortem interval, temperature, hydration, and cause of death. Explant organ culture has been effectively utilized to establish outgrowth cell cultures and characterize the histiotypic relationships between the various cell types within an organ or tissue.J. Resau is a visiting scientist at the NCI-LMO-DCE in Frederick, MD 21702, U.S.A.K. Sakamoto is a visiting scientist from the Department of Surgery, Gunma University School of Medicine, Maebashi, Japan 相似文献
5.
6.
7.
Janine JH Oosterhof G Jolanda Elving Ietse Stokroos Arie van nieuw Amerongen Henny C van der Mei Henk J Busscher 《Biofouling》2013,29(6):347-353
The integrity of biofilms on voice prostheses used to rehabilitate speech in laryngectomized patients causes unwanted increases in airflow resistance, impeding speech. Biofilm integrity is ensured by extracellular polymeric substances (EPS). This study aimed to determine whether synthetic salivary peptides or mucolytics, including N-acetylcysteine and ascorbic acid, influence the integrity of voice prosthetic biofilms. Biofilms were grown on voice prostheses in an artificial throat model and exposed to synthetic salivary peptides, mucolytics and two different antiseptics (chlorhexidine and Triclosan). Synthetic salivary peptides did not reduce the air flow resistance of voice prostheses after biofilm formation. Although both chlorhexidine and Triclosan reduced microbial numbers on the prostheses, only the Triclosan-containing positive control reduced the air flow resistance. Unlike ascorbic acid, the mucolytic N-acetylcysteine removed most EPS from the biofilms and induced a decrease in air flow resistance. 相似文献
8.
Topol LZ Bardot B Zhang Q Resau J Huillard E Marx M Calothy G Blair DG 《The Journal of biological chemistry》2000,275(12):8785-8793
Down-regulated by mos (Drm)/Gremlin is a highly conserved protein whose properties and expression pattern suggest a role in early development, tissue-specific differentiation, and cell transformation. We have investigated the biosynthesis and processing of Drm expressed endogenously in rat fibroblasts or overexpressed following transient or stable transfection. Analysis of metabolically labeled cells revealed that Drm exists in secreted and cell-associated forms that exhibit similar mobilities in SDS-polyacrylamide gel electrophoresis. Protein analysis indicated that Drm is present in two major species: a slow migrating glycosylated form and a nonglycosylated form. Both forms of Drm are able to undergo phosphorylation. Drm is released into the media within 30 min of synthesis and is detectable for up to 4-5 h, whereas the cell-associated form has a half-life of about 1 h. Confocal immunofluorescent microscopy indicates that Drm is present both on the external surface of expressing cells, as well as within the endoplasmic reticulum and the Golgi. Both glycosylated and nonglycosylated forms of Drm exhibit identical distributions and are able to antagonize bone morphogenetic protein signaling. Like the soluble form, the cell-associated forms are capable of binding (125)I-bone morphogenetic protein-4. These properties are consistent with a role for Drm in interfering with signaling and indicate that Drm may act at the cell surface during tissue development and transformation. 相似文献
9.
10.
Improved tests for heterogeneity across a region of DNA sequence in the ratio of polymorphism to divergence 总被引:15,自引:9,他引:6
The neutral theory of molecular evolution predicts that the ratio of
polymorphisms to fixed differences should be fairly uniform across a region
of DNA sequence. Significant heterogeneity in this ratio can indicate the
effects of balancing selection, selective sweeps, mildly deleterious
mutations, or background selection. Comparing an observed heterogeneity
statistic with simulations of the heterogeneity resulting from random
phylogenetic and sampling variation provides a test of the statistical
significance of the observed pattern. When simulated data sets containing
heterogeneity in the polymorphism-to-divergence ratio are examined,
different statistics are most powerful for detecting different patterns of
heterogeneity. The number of runs is most powerful for detecting patterns
containing several peaks of polymorphism; the Kolmogorov-Smirnov statistic
is most powerful for detecting patterns in which one end of the gene has
high polymorphism and the other end has low polymorphism; and a newly
developed statistic, the mean sliding G statistic, is most powerful for
detecting patterns containing one or two peaks of polymorphism with reduced
polymorphism on either side. Nine out of 27 genes from the Drosophila
melanogaster subgroup exhibit heterogeneity that is significant under at
least one of these three tests, with five of the nine remaining significant
after a correction for multiple comparisons, suggesting that detectable
evidence for the effects of some kind of selection is fairly common.
相似文献