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1.
Reconstructions of the human-African great ape phylogeny by using mitochondrial DNA (mtDNA) have been subject to considerable debate. One confounding factor may be the lack of data on intraspecific variation. To test this hypothesis, we examined the effect of intraspecific mtDNA diversity on the phylogenetic reconstruction of another Plio- Pleistocene radiation of higher primates, the fascicularis group of macaque (Macaca) monkey species. Fifteen endonucleases were used to identify 10 haplotypes of 40-47 restriction sites in M. mulatta, which were compared with similar data for the other members of this species group. Interpopulational, intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of divergence time and branching order incorporating this variation were substantially different from those based on single representatives of each species. We conclude that intraspecific mtDNA diversity is substantial in at least some primate species. Consequently, without prior information on the extent of genetic diversity within a particular species, intraspecific variation must be assessed and accounted for when reconstructing primate phylogenies. Further, we question the reliability of hominoid mtDNA phylogenies, based as they are on one or a few representatives of each species, in an already depauperate superfamily of primates.   相似文献   
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Several chemical compounds not known to interact with tumor necrosis factor (TNF) signal transducing proteins inhibit TNF-mediated activation of vascular endothelial cells (EC). Four structurally diverse agents, arachidonyl trifluoromethylketone, staurosporine, sodium salicylate, and C6-ceramide, were studied. All four agents caused EC apoptosis at concentrations that inhibited TNF-induced IkappaBalpha degradation. However, evidence of apoptosis was not evident until after several (e.g. 3-12) hours of treatment, whereas 2 h of treatment was sufficient to inhibit TNF responses. IL-1-induced IkappaBalpha degradation was unaffected by these treatments. Inhibition of TNF signaling could not be prevented with either of the broad spectrum caspase inhibitors zVADfmk or yVADcmk. The inhibition of p38 kinase with SB203580 prevented the inhibition of TNF signaling by all agents except arachidonyl trifluoromethylketone. No changes in the levels or molecular weights of the adaptor proteins TRADD (TNF receptor-associated death domain), RIP (receptor-interacting protein), or TRAF2 (TNF receptor-associated factor-2) were caused by apoptogenic drugs. However, TNF receptor 1 (TNFR1) surface expression was significantly reduced by all four agents. Furthermore, TNF-dependent recruitment of TRADD to surface TNFR1 was also inhibited. These data suggest that several putative inhibitors of TNF signaling work by triggering apoptosis and that an early event coincident with the initiation of apoptosis, preceding evidence of injury, is loss of TNFR1. Consistent with this hypothesis, cotreatment of EC with the metalloproteinase inhibitor Tapi (TNF-alpha proteinase inhibitor) blocked the reduction in surface TNFR1 by apoptogenic drugs and prevented inhibition of TNF-induced IkappaBalpha degradation without blocking apoptosis. TNFR1 loss could be a mechanism to limit inflammation in response to apoptotic cell death.  相似文献   
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There is currently interest in the metabolism of the various compounds which make up the vitamin E family, especially with regards to the possible use of vitamin E metabolites as markers of oxidative stress and adequate vitamin E supply. A number of vitamin E metabolites have been described to date and we have recently developed a method to extract and quantitate a range of vitamin E metabolites in human urine. During the development of this method a new metabolite of alpha-tocopherol was identified, which we tentatively characterised as 5-(6-hydroxy-2,5,7,8-tetramethyl-chroman-2-yl)-2-methyl-pentanoic acid (alpha-CMBHC).(1) Here we describe the synthesis of alpha-CMBHC as a standard and confirm that it is a metabolite of alpha-tocopherol.  相似文献   
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One of the diseases of veterinary and public health importance affecting the Kafue lechwe (Kobus leche kafuensis) on the Kafue flats is brucellosis, for which only scant information is available. During the 2003 (October), 2004 (December), and 2008 (July-December) hunting seasons in the Kafue flats, we conducted a study to determine the seroprevalence of Brucella spp. in the Kafue lechwe and to evaluate serologic tests for detection of Brucella spp. antibodies in lechwe. The Rose Bengal Test (RBT), competitive enzyme-linked immunosorbent assay (cELISA), and fluorescence polarization assay (FPA) were used. A total of 121 Kafue lechwe were hunted for disease investigations in 2003, 2004, and 2008 in the Kafue Flat Game Management Area. Of these, 21.6%, (95% confidence interval [CI]: 14.2-29.1%) had detectable antibodies to Brucella spp. The Kafue lechwe in Lochnivar National Park had higher antibody results than those in Blue Lagoon National Park (odds ratio=3.0; 95% CI: 0.94-9.4). Infection levels were similar in females (21.6%) and males (21.7%). Results were similar among RBT, FPA, cELISA tests, suggesting that these could effectively be used in diagnosing brucellosis in the Kafue lechwe. Our study demonstrates the presence of Brucella infections in the Kafue lechwe in two national parks located in the Kafue flats and further highlights the suitability of serologic assays for testing the Kafue lechwe. Because the Kafue lechwe is the most hunted wildlife species in Zambia, hunters need to be informed of the public health risk of Brucella spp. infection.  相似文献   
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Our knowledge of the ion channels, receptors and signalling mechanisms involved in pain pathophysiology, and which specific channels play a role in subtypes of pain such as neuropathic and inflammatory pain, has expanded considerably in recent years. It is now clear that in the neuropathic state the expression of certain channels is modified, and that these changes underlie the plasticity of responses that occur to generate inappropriate pain signals from normally trivial inputs. Pain is modulated by a subset of the voltage-gated sodium channels, including Nav1.3, Nav1.7, Nav1.8 and Nav1.9. These isoforms display unique expression patterns within specific tissues, and are either up- or down-regulated upon injury to the nervous system. Here we describe our current understanding of the roles of sodium channels in pain and nociceptive information processing, with a particular emphasis on neuropathic pain and drugs useful for the treatment of neuropathic pain that act through mechanisms involving block of sodium channels. One of the future challenges in the development of novel sodium channel blockers is to design and synthesise isoform-selective channel inhibitors. This should provide substantial benefits over existing pain treatments.  相似文献   
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Background  

A variety of approaches to understanding protein structure and function require production of recombinant protein. Mammalian based expression systems have advantages over bacterial systems for certain classes of protein but can be slower and more laborious. Thus the availability of a simple system for production and rapid screening of constructs or conditions for mammalian expression would be of great benefit. To this end we have coupled an efficient recombinant protein production system based on transient transfection in HEK-293 EBNA1 (HEK-293E) suspension cells with a dot blot method allowing pre-screening of proteins expressed in cells in a high throughput manner.  相似文献   
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Study design

A prospective treatment study with a new brace was conducted Objective. To evaluate radiological and subjective clinical results after one year conservative brace treatment with pressure onto lordosis at the thoracolumbar joint in children with scoliosis and kyphosis.

Summary of background data

Conservative brace treatment of adolescent scoliosis is not proven to be effective in terms of lasting correction. Conservative treatment in kyphotic deformities may lead to satisfactory correction. None of the brace or casting techniques is based on sagittal forces only applied at the thoracolumbar spine (TLI= thoracolumbar lordotic intervention). Previously we showed in patients with scoliosis after forced lordosis at the thoracolumbar spine a radiological instantaneous reduction in both coronal curves of double major scoliosis.

Methods

A consecutive series of 91 children with adolescent scoliosis and kyphosis were treated with a modified symmetric 30 degrees Boston brace to ensure only forced lordosis at the thoracolumbar spine. Scoliosis was defined with a Cobb angle of at least one of the curves [greater than or equal to] 25 degrees and kyphosis with or without a curve <25 degrees in the coronal plane. Standing radiographs were made i) at start, ii) in brace at beginning and iii) after one year treatment without brace.

Results

Before treatment start ??in brace?? radiographs showed a strong reduction of the Cobb angles in different curves in kyphosis and scoliosis groups (sagittal n = 5 all p < 0.001, pelvic obliquity p < 0.001). After one year of brace treatment in scoliosis and kyphosis group the measurements on radiographs made without brace revealed an improvement in 3 Cobb angles each.

Conclusion

Conservative treatment using thoracolumbar lordotic intervention in scoliotic and kyphotic deformities in adolescence demonstrates a marked improvement after one year also in clinical and postural criteria. An effect not obtained with current brace techniques.  相似文献   
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