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11.
This study is focused on the depositional model and paleoenvironmental distribution patterns of orbitolinids-rich microfacies in an Upper Cretaceous carbonate succession in the Kuh-e Mazar anticline in Kerman Province, Central Iran. Twelve microfacies indicating a tidal flat (including intertidal and supratidal) and an inner ramp (consisting of subtidal lagoon and orbitolinid–rudist barrier shoal) belonging to a shallow-water ramp-type carbonate platform were recognised. Generally, the orbitolinid associations in the carbonate ramp are indicative of shallow warm waters with normal salinity. The occurrence and abundance of thick or conical orbitolinids in both shoal and lagoon show that such associations were well adapted to different environmental conditions including different depth, substrate stability and water energy. The slightly discoidal, almost discoidal and discoidal forms were only present in the deeper depths of the environment including the lagoon with muddy and more stable substrates and lower water energy. However, the orbitolinids in the inner part of the carbonate ramp were scarce or almost absent in the deep inner to middle lagoon due to the deep restricted environmental conditions unfavourable for benthic marine life.  相似文献   
12.
Ghafari  R.  Kabutarkhani  F. Hassani  Mansouri  N. 《Cluster computing》2022,25(2):1035-1093
Cluster Computing - Cloud computing is very popular because of its unique features such as scalability, elasticity, on-demand service, and security. A large number of tasks are performed...  相似文献   
13.
Twenty three pyrimidine auxotrophs of Sinorhizobium meliloti Rmd201 were generated by random mutagenesis with transposon Tn5. On the basis of biochemical characters these auxotrophic mutants were classified into car, pyrC and pyrE/pyrF categories. All auxotrophs induced white nodules which were ineffective in nitrogen fixation. Light and electron microscopic studies revealed that the nodules induced by pyrC mutants were more developed than the nodules of car mutants. Similarly the nodules induced by pyrE/pyrF mutants had more advanced structural features than the nodules of pyrC mutants. The nodule development in case of pyrE/pyrF mutants was not to the extent observed in the parental strain. These results indicated that some of the intermediates and/or enzymes of pyrimidine biosynthetic pathway of S. meliloti play a key role in bacteroidal transformation and nodule development.  相似文献   
14.
2,2,7-trimethylguanosine (TMG) binding proteins from human cells were purified through TMG-affinity columns. TMG synthesis was improved and the TMG obtained was shown to be similar to the TMG in the 5' cap of the UsnRNAs. The eluates obtained with TMG-affinity chromatographies were very different from those isolated with m7G-affinity columns, thus suggesting that specific TMG-binding proteins were obtained. The fraction may be enriched with factors associated with import and/or hypermethylation of UsnRNPs.  相似文献   
15.
The three-phase partitioning (TPP) technique was used upstream to isolate/concentrate secreted proteins from Corynebacterium pseudotuberculosis cultured in a complex liquid medium. Several parameters of the TPP technique (15, 30, or 60% ammonium sulfate concentration; 4.0, 5.5, or 7.0 pH; and primary (n) or tertiary (t)-butanol solvent isomer) were varied to determine the optimal recovery of serologically and cellularly immunoreactive extracted proteins. A TPP extraction made with 30% ammonium sulfate and an initial pH of 4.0 gave the best humoral and cellular immunoreactivity of caseous lymphadenitis infected goats. In particular, two immunogenic secreted (16 and 125 kDa) proteins, which had not been found by other extraction methods, were identified.  相似文献   
16.
Ten isoleucine+valine and three leucine auxotrophs of Sinorhizobium meliloti Rmd201 were obtained by random mutagenesis with transposon Tn5 followed by screening of Tn5 derivatives on minimal medium supplemented with modified Holliday pools. Based on intermediate feeding, intermediate accumulation and cross-feeding studies, isoleucine+valine and leucine auxotrophs were designated as ilvB/ilvG, ilvC and ilvD, and leuC/leuD and leuB mutants, respectively. Symbiotic properties of all ilvD mutants with alfalfa plants were similar to those of the parental strain. The ilvB/ilvG and ilvC mutants were Nod-. Inoculation of alfalfa plants with ilvB/ilvG mutant did not result in root hair curling and infection thread formation. The ilvC mutants were capable of curling root hairs but did not induce infection thread formation. All leucine auxotrophs were Nod+ Fix-. Supplementation of leucine to the plant nutrient medium did not restore symbiotic effectiveness to the auxotrophs. Histological studies revealed that the nodules induced by the leucine auxotrophs did not develop fully like those induced by the parental strain. The nodules induced by leuB mutants were structurally more advanced than the leuC/leuD mutant induced nodules. These results indicate that ilvB/ilvG, ilvC and one or two leu genes of S. meliloti may have a role in symbiosis. The position of ilv genes on the chromosomal map of S. meliloti was found to be near ade-15 marker.  相似文献   
17.
Comparative mapping between model plant species for which the complete genome sequence is known and crop species has been suggested as a new strategy for the isolation of agronomically valuable genes. In this study, we tested whether comparative mapping between Arabidopsisand maize of a small region (754 kb) surrounding the DREB1A gene in Arabidopsis could lead to the identification of an orthologous region in maize containing the DREB1A homologue. The genomic sequence information available for Arabidopsis allowed for the selection of conserved, low-copy genes that were used for the identification of maize homologues in a large EST database. In total, 17 maize homologues were mapped. A second BLAST comparison of these genes to the recently completed Arabidopsis sequence revealed that 15 homologues are likely to be orthologous as the highest similarity score was obtained either with the original Arabidopsis gene or with a highly similar Arabidopsis gene localized on a duplication of the investigated region on chromosome 5. The map position of these genes showed a significant degree of orthology with the Arabidopsis region. Nevertheless, extensive duplications and rearrangements in the Arabidopsisand maize genomes as well as the evolutionary distance between Arabidopsis and maize make it unlikely that orthology and collinearity between these two species are sufficient to aid gene prediction and cloning in maize.  相似文献   
18.
Ten aromatic amino acid auxotrophs of Sinorhizobium meliloti (previously called Rhizobium meliloti) Rmd201 were generated by random mutagenesis with transposon Tn5 and their symbiotic properties were studied. Normal symbiotic activity, as indicated by morphological features, was observed in the tryptophan synthase mutants and the lone tyrosine mutant. The trpE and aro mutants fixed trace amounts of nitrogen whereas the phe mutant was completely ineffective in nitrogen fixation. Histology of the nodules induced by trpE and aro mutants exhibited striking similarities. Each of these nodules contained an extended infection zone and a poorly developed nitrogen fixation zone. Transmission electron microscopic studies revealed that the bacteroids in the extended infection zone of these nodules did not show maturation tendency. A leaky mutant, which has a mutation in trpC, trpD, or trpF gene, was partially effective in nitrogen fixation. The histology of the nodules induced by this strain was like that of the nodules induced by the parental strain but the inoculated plants were stunted. These studies demonstrated the involvement of anthranilic acid and at least one more intermediate of tryptophan biosynthetic pathway in bacteroidal maturation and nitrogen fixation in S. meliloti. The alfalfa plant host seems to provide tryptophan and tyrosine but not phenylalanine to bacteroids in nodules.  相似文献   
19.
A new method for detection of temporomandibular disorder based on singular spectrum analysis is presented. In this method the motion data of markers placed on the points of special interest on the faces of several subjects is extracted and analysed. The individuals are classified into a group of healthy subjects and a group of those with temporomandibular disorder by extracting the signal components of the original time series and separating the noise using the proposed technique. The results for both simulated and real data verify the effectiveness of the proposed algorithm.  相似文献   
20.

Background

The Norwegian Knowledge Centre for the Health Services (NOKC) reports 30-day survival as a quality indicator for Norwegian hospitals. The indicators have been published annually since 2011 on the website of the Norwegian Directorate of Health (www.helsenorge.no), as part of the Norwegian Quality Indicator System authorized by the Ministry of Health. Openness regarding calculation of quality indicators is important, as it provides the opportunity to critically review and discuss the method. The purpose of this article is to describe the data collection, data pre-processing, and data analyses, as carried out by NOKC, for the calculation of 30-day risk-adjusted survival probability as a quality indicator.

Methods and Findings

Three diagnosis-specific 30-day survival indicators (first time acute myocardial infarction (AMI), stroke and hip fracture) are estimated based on all-cause deaths, occurring in-hospital or out-of-hospital, within 30 days counting from the first day of hospitalization. Furthermore, a hospital-wide (i.e. overall) 30-day survival indicator is calculated. Patient administrative data from all Norwegian hospitals and information from the Norwegian Population Register are retrieved annually, and linked to datasets for previous years. The outcome (alive/death within 30 days) is attributed to every hospital by the fraction of time spent in each hospital. A logistic regression followed by a hierarchical Bayesian analysis is used for the estimation of risk-adjusted survival probabilities. A multiple testing procedure with a false discovery rate of 5% is used to identify hospitals, hospital trusts and regional health authorities with significantly higher/lower survival than the reference. In addition, estimated risk-adjusted survival probabilities are published per hospital, hospital trust and regional health authority. The variation in risk-adjusted survival probabilities across hospitals for AMI shows a decreasing trend over time: estimated survival probabilities for AMI in 2011 varied from 80.6% (in the hospital with lowest estimated survival) to 91.7% (in the hospital with highest estimated survival), whereas it ranged from 83.8% to 91.2% in 2013.

Conclusions

Since 2011, several hospitals and hospital trusts have initiated quality improvement projects, and some of the hospitals have improved the survival over these years. Public reporting of survival/mortality indicators are increasingly being used as quality measures of health care systems. Openness regarding the methods used to calculate the indicators are important, as it provides the opportunity of critically reviewing and discussing the methods in the literature. In this way, the methods employed for establishing the indicators may be improved.  相似文献   
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