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1.
A new real-time PCR based method was developed for the species-specific detection, identification and quantification of Fusarium graminearum in planta. It utilizes a TaqMan hybridisation probe targeting the beta-tubulin gene and a plasmid standard. The assay is highly specific giving no product with DNA of closely related species. It is very sensitive, detecting down to five gene copies per reaction, and is able to produce reliable quantitative data over a range of six orders of magnitude.  相似文献   
2.
One of the most complex issues in the cloud computing environment is the problem of resource allocation so that, on one hand, the cloud provider expects the most profitability and, on the other hand, users also expect to have the best resources at their disposal considering the budget constraints and time. In most previous work conducted, heuristic and evolutionary approaches have been used to solve this problem. Nevertheless, since the nature of this environment is based on economic methods, using such methods can decrease response time and reducing the complexity of the problem. In this paper, an auction-based method is proposed which determines the auction winner by applying game theory mechanism and holding a repetitive game with incomplete information in a non-cooperative environment. In this method, users calculate suitable price bid with their objective function during several round and repetitions and send it to the auctioneer; and the auctioneer chooses the winning player based the suggested utility function. In the proposed method, the end point of the game is the Nash equilibrium point where players are no longer inclined to alter their bid for that resource and the final bid also satisfies the auctioneer’s utility function. To prove the response space convexity, the Lagrange method is used and the proposed model is simulated in the cloudsim and the results are compared with previous work. At the end, it is concluded that this method converges to a response in a shorter time, provides the lowest service level agreement violations and the most utility to the provider.  相似文献   
3.
Jasmonates are plant stress hormones that induce suppression of proliferation and death in cancer cells, while being selectively inactive towards non-transformed cells. Jasmonates can overcome apoptotic blocks and exert cytotoxic effects on drug-resistant cells expressing p53 mutations. Jasmonates induce a rapid depletion of ATP in cancer cells. Indeed, this steep drop occurs when no signs of cell death are detectable yet. Experiments using modulators of ATP synthesis via glycolysis or oxidative phosphorylation suggest that the latter is the pathway suppressed by jasmonates. Consequently, the direct effects of jasmonates on mitochondria were evaluated. Jasmonates induced cytochrome c release and swelling in mitochondria isolated from cancer cells but not from normal ones. Thus, the selectivity of jasmonates against cancer cells is rooted at the mitochondrial level, and probably exploits differences between mitochondria from normal versus cancer cells. These findings position jasmonates as promising anti-cancer drugs acting via energetic depletion in neoplastic cells.  相似文献   
4.

Background  

Parkinson's disease (PD) is the second most common neurodegenerative disorder. As there is no definitive diagnostic test, its diagnosis is based on clinical criteria. Recently transcranial duplex scanning (TCD) of the substantia nigra in the brainstem has been proposed as an instrument to diagnose PD. We and others have found that TCD scanning of substantia nigra duplex is a relatively accurate diagnostic instrument in patients with parkinsonian symptoms. However, all studies on TCD so far have involved well-defined, later-stage PD patients, which will obviously lead to an overestimate of the diagnostic accuracy of TCD.  相似文献   
5.

Background

Neuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain.

Methods

We translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles.

Results

Using a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91%) and acceptable specificity (70%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct.

Conclusions

The NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain.  相似文献   
6.
A quantitative TaqMan minor-groove binder real-time PCR assay was developed for the sensitive detection of a ruminant-specific genetic marker in fecal members of the phylum Bacteroidetes. The qualitative and quantitative detection limits determined were 6 and 20 marker copies per PCR, respectively. Tested ruminant feces contained an average of 4.1 × 109 marker equivalents per g, allowing the detection of 1.7 ng of feces per filter in fecal suspensions. The marker was detected in water samples from a karstic catchment area at levels matching a gradient from negligible to considerable ruminant fecal influence (from not detectable to 105 marker equivalents per liter).  相似文献   
7.

Background  

The zebrafish, Danio rerio, is used as a model organism to study vertebrate genetics and development. An effective enhancer trap (ET) in zebrafish using the Tol2 transposon has been demonstrated. This approach could be used to study embryogenesis of a vertebrate species in real time and with high resolution.  相似文献   
8.
The use of strong promoter systems for recombinant protein production generates high product yields, but also overburdens the host cell metabolism and compromises production. Escherichia coli has highly developed regulatory pathways that are immediately responsive to adverse conditions. To gain insight into stress response mechanisms and to detect marker genes and proteins for stress specific monitoring time course analysis of controlled chemostat cultivations was performed using E. coli total microarray and difference gel electrophoresis (Ettan™ DIGE). In order to detect differences and consistencies of stress response as well as the impact of the inducer isopropyl-β-d-thiogalactopyranosid on cells, expression of two recombinant proteins (hSOD and GFPmut3.1) was investigated. Genes involved in aerobic metabolism under control of the ArcB/ArcA two component system were found to be down-regulated, and the interplay of the psp operon, ArcA system and guanosine tetraphosphate is suggested to be involved in stress regulatory mechanisms. A distinct impact of the two recombinant proteins was observed, particularly on levels of known stress regulatory genes and proteins, as well as on the response associated with ArcA and psp. Altogether, 62 genes as well as seven proteins showed consistent expression levels due to recombinant gene expression, and are therefore suggested to be appropriate monitoring targets.  相似文献   
9.
10.
SEPALLATA3: the 'glue' for MADS box transcription factor complex formation   总被引:1,自引:0,他引:1  

Background  

Plant MADS box proteins play important roles in a plethora of developmental processes. In order to regulate specific sets of target genes, MADS box proteins dimerize and are thought to assemble into multimeric complexes. In this study a large-scale yeast three-hybrid screen is utilized to provide insight into the higher-order complex formation capacity of the Arabidopsis MADS box family. SEPALLATA3 (SEP3) has been shown to mediate complex formation and, therefore, special attention is paid to this factor in this study.  相似文献   
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