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81.
Stroke is a common complex trait and does not follow Mendelian pattern of inheritance. Gene–gene or gene–environment interactions may be responsible for the complex trait. How the interactions contribute to stroke is still under research. This study aimed to explore the association between gene–gene interactions and stroke in Chinese in a large case–control study. Nearly 4,000 participants were recruited from seven clinical centers. Eight variants in five candidate genes were examined for stroke risk. Gene–gene interactions were explored by using Generalized Multifactor Dimensionality Reduction (GMDR). A significant gene–gene interaction was found by GMDR. The best model including MTHFR C677T, ALOX5AP T2354A and NOTCH3 C381T scored 10 for Cross-Validation Consistency and 9 for Sign Test (P = 0.0107). The individuals with combination of MTHFR 677TT, ALOX5AP 2354AA and NOTCH3 381TT/TC had a significantly higher risk of thrombotic stroke (OR 3.165, 95% CI 1.461–6.858, P = 0.003). Our results show that combination of these alleles conferred higher risk for stroke than single risk allele. The gene–gene interaction may serve as a novel area for stroke research. The three-locus combination may change the susceptibility of particular subjects to the disease.  相似文献   
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ABO blood group incompatibility is not a contraindication for allogeneic hematopoietic stem cell transplantation (allo-HSCT). An increasing number of ABO-incompatible HSCT (ABOi-HSCT) procedures have been performed along with advances in donor selection over the years. Currently, whether the recipient-donor ABO incompatibility has detrimental effects on post-HSCT outcomes is a matter of debate. Discrepancies across studies referring to various graft sources, donor types, conditioning regimens, and the use of immunomodulators complicate interpretations of the clinical outcomes of ABOi-HSCT, such as transfusion requirements, graft-versus-host disease (GVHD), disease relapse, overall survival (OS), and non-relapse mortality (NRM). Isohemagglutinins (ISO) targeting red blood cell (RBC) antigens are associated with post-HSCT immunohematological complications, including hemolysis, passenger lymphocyte syndrome (PLS), and pure red cell aplasia (PRCA). Immunohematological events occur frequently and are sometimes difficult to handle in clinical practice. Therefore, it is necessary to form a deeper understanding on the mechanism and a comprehensive management scheme for recipients of ABOi-HSCT. In this review, we summarized literature of the impact of ABO incompatibility on post-HSCT outcomes and outlined important immune-mediated hematological events.  相似文献   
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Incorrect species delimitation will lead to inappropriate conservation decisions, especially for threatened species. The takin (Budorcas taxicolor) is a large artiodactyl endemic to the Himalayan–Hengduan–Qinling Mountains and is well known for its threatened status and peculiar appearance. However, the speciation, intraspecies taxonomy, evolutionary history, and adaptive evolution of this species still remain unclear, which greatly hampers its scientific conservation. Here, we de novo assembled a high-quality chromosome-level genome of takin and resequenced the genomes of 75 wild takins. Phylogenomics revealed that takin was positioned at the root of Caprinae. Population genomics based on the autosome, X chromosome, and Y chromosome SNPs and mitochondrial genomes consistently revealed the existence of two phylogenetic species and recent speciation in takins: the Himalayan takin (B. taxicolor) and the Chinese takin (B. tibetana), with the support of morphological evidence. Two genetically divergent subspecies were identified in both takin species, rejecting three previously proposed taxonomical viewpoints. Furthermore, their distribution boundaries were determined, suggesting that large rivers play important roles in shaping the genetic partition. Compared with the other subspecies, the Qinling subspecies presented the lowest genomic diversity, higher linkage disequilibrium, inbreeding, and genetic load, thus is in urgent need of genetic management and protection. Moreover, coat color gene (PMEL) variation may be responsible for the adaptive coat color difference between the two species following Gloger’s rule. Our findings provide novel insights into the recent speciation, local adaptation, scientific conservation of takins, and biogeography of the Himalaya–Hengduan biodiversity hotspot.  相似文献   
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The abnormal expression of long noncoding RNAs (lncRNAs) plays an important role in the regulation of human cancer progression and drug resistance. The lncRNA OPI5-AS1 is a crucial regulator in some cancers; however, its role in cisplatin resistance of osteosarcoma remains unclear. We found that OIP5-AS1 was significantly upregulated in cisplatin-resistant (CR) osteosarcoma cells MG63-CR and SaOS2-CR compared with the corresponding parental cells. OIP5-AS1 silencing suppressed cell growth in vitro and in vivo, and promoted apoptosis of MG63-CR and SaOS2-CR cells, indicating that knockdown of OIP5-AS1 significantly decreased cisplatin resistance in MG63-CR and SaOS2-CR cells. This conclusion was supported by the decreased expression of the drug resistance-related factors multidrug resistance-associated protein 1 (MRP1) and P-glycoprotein (P-gp) upon OIP5-AS1 silencing. In addition, OIP5-AS1 downregulation suppressed the PI3K/AKT/mTOR signaling pathway. Importantly, we demonstrated that OIP5-AS1 functions as a competing endogenous RNA of miR-340-5p and regulates the expression of lysophosphatidic acid acyltransferase (LPAATβ), which is a target of miR-340-5p. Moreover, downregulation of miR-340-5p partly reversed the inhibitory effect of OIP5-AS1 knockdown on the PI3K/AKT/mTOR pathway and therefore counteracted cisplatin resistance in MG63-CR and SaOS2-CR cells. In conclusion, OIP5-AS1 causes cisplatin resistance in osteosarcoma through inducing the LPAATβ/PI3K/AKT/mTOR signaling pathway by sponging the miR-340-5p. Our results contribute to a better understanding of the function and mechanism of OIP5-AS1 in osteosarcoma cisplatin resistance.  相似文献   
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Synopsis Small fish abundance is usually high in heavily vegetated habitats in Yangtze lakes, China. Visual and swimming barriers created by dense macrophytes beds could reduce feeding efficiency and growth of small fishes. We tested the hypothesis that small fishes in habitats with dense macrophytes would show decreased feeding efficiency and reduced growth rates by comparing feeding efficiency (measured as the relative weight of fore-gut contents), total length, and condition factor of four small young-of-the-year fishes collected in the near-shore (heavily vegetated) and central (less vegetated) areas of Liangzi Lake. Feeding efficiency, total length, or condition factor were each significantly reduced in the near-shore area compared with the central area for Ctenogobius giurinus, Pseudorasbora parva and Carassius auratus auratus. This supports our hypothesis that vegetation abundance may mediate feeding efficiency and growth of small fishes. Although Hypseleotris swinhonis did not show significant decreases in feeding efficiency or growth in the near-shore area, there was not any reversed tendency, i.e. increased feeding rate or growth in the near-shore area compared to the central area. Yibo Cui: Deceased  相似文献   
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Ciliates (protozoa) are ubiquitous components of plankton community and play important roles in aquatic ecosystems in regards of their abundance, biomass, diversity and energy turnover. Based on the stratified samples collected from the northern Beibu Gulf in August 2011, species composition, abundance, biomass, diversity and spatial pattern of planktonic ciliates were studied. Furthermore the main environmental factors controlling ciliate communities were determined. A total of 101 species belonging to 44 genera and 7 orders (i.e., Oligotrichida, Haptorida, Euplotida, Sessilida, Pleurostomatida, Scuticociliatida and Tintinnida) were identified. The variation of ciliate communities was significant at horizontal level, but that was not at vertical level. Based on cluster analysis, ciliate communities were divided into three main groups. Redundancy analysis (RDA) revealed that Group A, existing in the waters with higher concentration of phosphorus and nitrogen, was dominated by Tintinnidium primitivum. Group B in the waters with lower temperature and chlorophyll-a concentration, was dominated by Leegaardiella ovalis. Group C, existing in the waters with higher temperature and chlorophyll-a concentration, was dominated by large Strombidium spp. and Mesodinium rubrum. Combining multiple analytic methods, our results strongly supported that phosphorus, nitrogen and chlorophyll-a were the most significant factors affecting the ciliate communities in the northern Beibu Gulf in summer. Concentration of phosphorus and nitrogen primarily influenced ciliate biomass, implying a potential impact of eutrophication on ciliate growth. The correlation with chlorophyll-a concentration, on one hand indicate the response of ciliates to the food availability, and on the other hand, the ciliates containing chloroplasts or endosymbionts may contribute greatly to the chlorophyll-a.  相似文献   
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