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81.
The giant liver fluke, Fascioloides magna, a liver parasite of free-living and domestic ruminants of Europe and North America, was analysed in order to determine the origin of European populations and to reveal the biogeography of this originally North American parasite on the European continent. The variable fragments of the mitochondrial cytochrome c oxidase subunit I (cox1; 384bp) and nicotinamide dehydrogenase subunit I (nad1; 405bp) were used. Phylogenetic trees and haplotype networks were constructed and the level of genetic structuring was evaluated using population genetic tools. In F. magna individuals originating from all European foci of infection (Italy, Czech Republic and Danube floodplain forests involving the territories of Slovakia, Hungary and Croatia) and from four of five major North American enzootic areas, 16 cox1 and 18 nad1 haplotypes were determined. The concatenated sequence set produced 22 distinct haplotypes. The European fluke populations were less diverse than those from North America in that they contained proportionately fewer haplotypes (eight), while a more substantial level of genetic diversity and a greater number of haplotypes (15) were recorded in North America. Only one haplotype was shared between the European (Italy) and North American (USA/Oregon and Canada/Alberta) flukes, supporting a western North American origin of the Italian F. magna population. Haplotypes found in Italy were distinct from those determined in the remaining European localities which indicates that introduction of F. magna to the European continent occurred more than once. In the Czech focus of infection, a south-eastern USA origin was revealed. Identical haplotypes, common to parasites from the Czech Republic and from an expanding focus in Danube floodplain forests, implies that the introduction of F. magna to the Danube region came from an already established Czech focus of infection.  相似文献   
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83.
Since the early 20th century, barley (Hordeum vulgare) has been a model for investigating the effects of physical and chemical mutagens and for exploring the potential of mutation breeding in crop improvement. As a consequence, extensive and well-characterized collections of morphological and developmental mutants have been assembled that represent a valuable resource for exploring a wide range of complex and fundamental biological processes. We constructed a collection of 881 backcrossed lines containing mutant alleles that induce a majority of the morphological and developmental variation described in this species. After genotyping these lines with up to 3,072 single nucleotide polymorphisms, comparison to their recurrent parent defined the genetic location of 426 mutant alleles to chromosomal segments, each representing on average <3% of the barley genetic map. We show how the gene content in these segments can be predicted through conservation of synteny with model cereal genomes, providing a route to rapid gene identification.  相似文献   
84.
85.

Background

The absence of horns, called polled phenotype, is the favored trait in modern cattle husbandry. To date, polled cattle are obtained primarily by dehorning calves. Dehorning is a practice that raises animal welfare issues, which can be addressed by selecting for genetically hornless cattle. In the past 20 years, there have been many studies worldwide to identify unique genetic markers in complete association with the polled trait in cattle and recently, two different alleles at the POLLED locus, both resulting in the absence of horns, were reported: (1) the Celtic allele, which is responsible for the polled phenotype in most breeds and for which a single candidate mutation was detected and (2) the Friesian allele, which is responsible for the polled phenotype predominantly in the Holstein-Friesian breed and in a few other breeds, but for which five candidate mutations were identified in a 260-kb haplotype. Further studies based on genome-wide sequencing and high-density SNP (single nucleotide polymorphism) genotyping confirmed the existence of the Celtic and Friesian variants and narrowed down the causal Friesian haplotype to an interval of 145 kb.

Results

Almost 6000 animals were genetically tested for the polled trait and we detected a recombinant animal which enabled us to reduce the Friesian POLLED haplotype to a single causal mutation, namely a 80-kb duplication. Moreover, our results clearly disagree with the recently reported perfect co-segregation of the POLLED mutation and a SNP at position 1 390 292 bp on bovine chromosome 1 in the Holstein-Friesian population.

Conclusion

We conclude that the 80-kb duplication, as the only remaining variant within the shortened Friesian haplotype, represents the most likely causal mutation for the polled phenotype of Friesian origin.  相似文献   
86.
The golden jackal, widely distributed in Europe, Asia and Africa, is one of the less studied carnivores in the world and the genetic structure of the European populations is unknown. In the last century jackals strongly declined mainly due to human persecution, but recently they expanded again in eastern Europe. With the aim to determine the genetic structure and the origin of expanding jackals, we analyzed population samples obtained from Bulgaria, Serbia, Croatia (Dalmatia and Slavonia) and individuals sampled in north-eastern Italy. Samples were typed at the hypervariable part of the mitochondrial DNA control-region (mtDNA CR1) and at 15 canine autosomal microsatellite loci (STR), and analyzed using multivariate, Bayesian and landscape genetic methods. The mtDNA CR1 was monomorphic, showing a single haplotype shared among all the populations. The STR loci were variable, with 2–14 alleles and intermediate values of heterozygosity (Ho = 0.47; He = 0.51). Genetic diversity was significantly partitioned (θST = 0.07; P < 0.001) and the populations were partially distinct, perhaps in consequence of recent fragmentations. Jackals from Dalmatia were the most genetically differentiated. Assignment testing and gene flow analyses suggested that jackals colonizing Italy have admixed origins from Dalmatian and Slavonian populations. They are not first generation migrants, suggesting that dispersal towards north-eastern Italy is a stepping-stone process. Golden jackal and wolf colonization patterns might be different, with prevalent short-distance dispersal in jackals versus prevalent long distance dispersal in wolves. The admixed origin of jackals in the Alps ensures abundant genetic variability, which may enhance adaptive fitness and expectancy of population growth. The intersections between Dinaric–Balkan and Eastern Alps are areas of population expansion and admixture, highlighting their conservation, ecological and evolutionary values.  相似文献   
87.
InterPro, an integrated documentation resource of protein families, domains and functional sites, was created in 1999 as a means of amalgamating the major protein signature databases into one comprehensive resource. PROSITE, Pfam, PRINTS, ProDom, SMART and TIGRFAMs have been manually integrated and curated and are available in InterPro for text- and sequence-based searching. The results are provided in a single format that rationalises the results that would be obtained by searching the member databases individually. The latest release of InterPro contains 5629 entries describing 4280 families, 1239 domains, 95 repeats and 15 post-translational modifications. Currently, the combined signatures in InterPro cover more than 74% of all proteins in SWISS-PROT and TrEMBL, an increase of nearly 15% since the inception of InterPro. New features of the database include improved searching capabilities and enhanced graphical user interfaces for visualisation of the data. The database is available via a webserver (http://www.ebi.ac.uk/interpro) and anonymous FTP (ftp://ftp.ebi.ac.uk/pub/databases/interpro).  相似文献   
88.
Determination of anti-citrullinated peptides (anti-CCP) specificity as a predictor of joint erosive changes, correlation between their serum level and radiological damages as well as disease activity score (DAS28). A trial has been conducted on a 211 patient sample fulfilling ACR criteria for rheumatoid arthritis (RA). There was assigned anti-CCP serum level, disease activity score by the formula for DAS28(3)-CRP and assessed radiological changes degree after Steinbrocker score. In 132 patient (62.559%) the serum anti-CCP concentration was positive for RA. Specificity of the test was 100% and sensitivity 65% (Z = 0.731, p = 0.465). There is a medium intensity correlation between variables representing anti-CCP and Steinbrocker score. Pearson's coefficient was 0.479 and Spearman's rank correlation coefficient was 0.614, i.e. statistically significant (p = 0.000). There is no statistically significant correlation between variables representing anti-CCP and DAS28(3)-CRP Anti-CCP are good RA predictor and their concentration correlate with radiological damages degree.  相似文献   
89.
The aim of the study was to assess the role of fruit drinks in daily diet of Osijek inhabitants. A special questionnaire was administered to 199 patients visiting a family physician's office during December 2003. The concentration of vitamin C (L-ascorbic acid) was determined in 42 commercially available fruit drinks. Only 11% (22/199) of study subjects did not take fruit drinks. The mean concentration of vitamin C in all samples was 150.10 +/- 166.83 mg/L. The questionnaire revealed that 89% (177/199) of study subjects using fruit drinks were taking a mean of 0.4 L of fruit drink per day, yielding a mean of 60.04 mg of vitamin C, i.e. 100% of the recommended daily allowance of 60 mg. Study results indicated fruit drinks to be a significant source of vitamin C in daily diet, however, great variation in vitamin C intake according to socioeconomic status of study subjects and type of fruit drink should be noted.  相似文献   
90.
A population genetic analysis based on sequences of the mitochondrial control region in 110 red foxes from five sampling localities in northern Serbia was carried out. The analysis yielded nine different haplotypes. Neither haplotype phylogeny nor their distribution was in accordance with the geographic location of the populations. In particular, the data failed to detect an unequivocal influence of the two big rivers, the Danube and the Tisza, separating the populations studied. Population differentiation was altogether low, without any relationship to the rivers as possible migration barriers. Although the possibility of foxes crossing the rivers over bridges or by swimming, thus keeping up gene flow, cannot be ruled out, it is most probable that the control region sequences are not sensitive enough to resolve small-scale population relationships but rather show patterns determined by stochastic processes such as genetic drift or lineage sorting.  相似文献   
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