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991.
Anna Lopatina Vjacheslav Krylenkov Konstantin Severinov 《Research in microbiology》2013,164(9):949-958
The diversity and temporal dynamics of bacterial communities in pristine snow around two Russian Antarctic stations was investigated. Taxonomic analysis of rDNA libraries revealed that snow communities were dominated by bacteria from a small number of operational taxonomic units (OTUs) that underwent dramatic swings in abundance between the 54th (2008–2009) and 55th (2009–2010) Russian Antarctic expeditions. Moreover, analysis of the 55th expedition samples indicated that there was very little, if any, correspondence in abundance of clones belonging to the same OTU present in rDNA and rRNA libraries. The latter result suggests that most rDNA clones originate from bacteria that are not alive and/or active and may have been deposited on the snow surface from the atmosphere. In contrast, clones most abundant in rRNA libraries (mostly belonging to Variovorax, Janthinobacterium, Pseudomonas, and Sphingomonas genera) may be considered as endogenous Antarctic snow inhabitants. 相似文献
992.
Mariusz Baumgart Michał Szpinda Anna Szpinda 《Surgical and radiologic anatomy : SRA》2013,35(3):191-203
Purpose
Detailed knowledge on the normative growth of the spine is of great relevance in the prenatal diagnosis of its abnormalities. The present study was conducted to compile age-specific reference data for vertebra C4 and its three ossification centers in human fetuses.Materials and methods
With the use of CT (Biograph mCT), digital image analysis (Osirix 3.9) and statistical analysis (Wilcoxon signed-rank test, Kolmogorov–Smirnov test, Levene’s test, Student’s t test, one-way ANOVA, post hoc RIR Tukey test, linear and nonlinear regression analysis), the normative growth of vertebra C4 and its three ossification centers in 55 spontaneously aborted human fetuses (27 males, 28 females) aged 17–30 weeks was examined.Results
Significant differences in neither sex nor laterality were found. The height and transverse and sagittal diameters of the C4 vertebral body increased logarithmically as: y = ?3.866 + 2.225 × ln(Age) ± 0.238 (R 2 = 0.69), y = ?7.077 + 3.547 × ln(Age) ± 0.356 (R 2 = 0.72) and y = ?3.886 + 2.272 × ln(Age) ± 0.222 (R 2 = 0.73), respectively. The C4 vertebral body grew linearly in cross-sectional area as y = ?7.205 + 0.812 × Age ± 1.668 (R 2 = 0.76) and four-degree polynomially in volume as y = 14.108 + 0.00007 × Age4 ± 6.289 (R 2 = 0.83). The transverse and sagittal diameters, cross-sectional area and volume of the ossification center of the C4 vertebral body generated the following functions: y = ?8.836 + 3.708 × ln(Age) ± 0.334 (R 2 = 0.76), y = ?7.748 + 3.240 × ln(Age) ± 0.237 (R 2 = 0.83), y = ?4.690 + 0.437 × Age ± 1.172 (R 2 = 0.63) and y = ?5.917 + 0.582 × Age ± 1.157 (R 2 = 0.77), respectively. The ossification center-to-vertebral body volume ratio gradually declined with age. On the right and left, the neural ossification centers showed the following growth: y = ?19.601 + 8.018 × ln(Age) ± 0.369 (R 2 = 0.92) and y = ?15.804 + 6.912 × ln(Age) ± 0.471 (R 2 = 0.85) for length, y = ?5.806 + 2.587 × ln(Age) ± 0.146 (R 2 = 0.88) and y = ?5.621 + 2.519 × ln(Age) ± 0.146 (R 2 = 0.88) for width, y = ?9.188 + 0.856 × Age ± 2.174 (R 2 = 0.67) and y = ?7.570 + 0.768 × Age ± 2.200 (R 2 = 0.60) for cross-sectional area, and y = ?13.802 + 1.222 × Age ± 1.872 (R 2 = 0.84) and y = ?11.038 + 1.061 × Age ± 1.964 (R 2 = 0.80) for volume, respectively.Conclusions
The morphometric parameters of vertebra C4 and its three ossification centers show no sex differences. The C4 vertebral body increases logarithmically in height and both sagittal and transverse diameters, linearly in cross-sectional area, and four-degree polynomially in volume. The three ossification centers of vertebra C4 grow logarithmically in both transverse and sagittal diameters, and linearly in both cross-sectional area and volume. The age-specific reference intervals for evolving vertebra C4 may be useful in the prenatal diagnosis of congenital spinal defects. 相似文献993.
Anna Papa Kyriaki Xanthopoulou Aikaterini Tsioka Stella Kalaitzopoulou Spiros Mourelatos 《Parasitology research》2013,112(4):1551-1555
Epidemics of West Nile virus (WNV) occurred for two consecutive years in Greece (in 2010 and 2011). A total of 16,116 adult Culex pipiens mosquitoes collected in two peripheries, Central Macedonia and Thessaly, were tested for WNV infection. WNV lineage 2 was detected in 6/296 mosquito pools, three in each year. The H249P substitution in the NS3 protein, previously associated with increased pathogenicity and thermotolerance, was detected in all six WNV-positive mosquito pools. When 21 individual C. pipiens mosquitoes were tested for the locus CQ11 to distinguish between the two C. pipiens forms, pipiens and molestus, 71.4 % were identified as pipiens, 4.7 % as molestus, and 19 % as hybrid pipiens/molestus, giving the first evidence that both C. pipiens biotypes are present in Greece, with a significant proportion being hybrids. The exact role of the C. pipiens forms and hybrids in the WNV epidemiology, in combination or not with the H249P substitution in the virus genome, remains to be elucidated. 相似文献
994.
Claudio Toma Alex D. Shaw Anna Heath Kerrie D. Pierce Philip B. Mitchell Peter R. Schofield Janice M. Fullerton 《Journal of psychiatry & neuroscience : JPN》2021,46(2):247
BackgroundBipolar disorder is a highly heritable psychiatric condition for which specific genetic factors remain largely unknown. In the present study, we used combined whole-exome sequencing and linkage analysis to identify risk loci and dissect the contribution of common and rare variants in families with a high density of illness.MethodsOverall, 117 participants from 15 Australian extended families with bipolar disorder (72 with affective disorder, including 50 with bipolar disorder type I or II, 13 with schizoaffective disorder–manic type and 9 with recurrent unipolar disorder) underwent whole-exome sequencing. We performed genome-wide linkage analysis using MERLIN and conditional linkage analysis using LAMP. We assessed the contribution of potentially functional rare variants using a gene-based segregation test.ResultsWe identified a significant linkage peak on chromosome 10q11-q21 (maximal single nucleotide polymorphism = rs10761725; exponential logarithm of the odds [LODexp] = 3.03; empirical p = 0.046). The linkage interval spanned 36 protein-coding genes, including a gene associated with bipolar disorder, ankyrin 3 (ANK3). Conditional linkage analysis showed that common ANK3 risk variants previously identified in genome-wide association studies — or variants in linkage disequilibrium with those variants — did not explain the linkage signal (rs10994397 LOD = 0.63; rs9804190 LOD = 0.04). A family-based segregation test with 34 rare variants from 14 genes under the linkage interval suggested rare variant contributions of 3 brain-expressed genes: NRBF2 (p = 0.005), PCDH15 (p = 0.002) and ANK3 (p = 0.014).LimitationsWe did not examine non-coding variants, but they may explain the remaining linkage signal.ConclusionCombining family-based linkage analysis with next-generation sequencing data is effective for identifying putative disease genes and specific risk variants in complex disorders. We identified rare missense variants in ANK3, PCDH15 and NRBF2 that could confer disease risk, providing valuable targets for functional characterization. 相似文献
995.
Constanze A. Jakwerth Adam M. Chaker Ferdinand Guerth Madlen Oelsner Lisa Pechtold Lynn S. zur Bonsen Julia T. Ullmann Susanne Krauss-Etschmann Anna Erb Josephine Kau Mirjam Plaschke Marlene Winkler Alexandra Kurz Antonia Kloss Julia Esser-von Bieren Carsten B. Schmidt-Weber Ulrich M. Zissler 《Clinical and experimental allergy》2021,51(12):1577-1591
996.
997.
Tomasz Cłapa Jakub Michalski Anna Syguda Dorota Narożna Peter van Oostrum Erik Reimhult 《Research in microbiology》2021,172(3):103817
Pseudomonas aeruginosa is a multi-drug resistant (MDR) pathogen. It is classified by WHO as one of the most life-threatening pathogens causing nosocomial infections. Some of its clinical isolates and their subpopulations show high persistence to many antibiotics that are recommended by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Thus, there is a need for non-traditional classes of antibiotics to fight the increasing threat of MDR P. aeruginosa. Ionic liquids (IL) are one such promising class of novel antibiotics. We selected four strains of P. aeruginosa and studied the growth inhibition and other effects of 12 different ILs. We used the well-characterized P. aeruginosa PAO1 (ATCC 15692) as model strain and compared it to three other isolates from chronic lung infection (LES B58), skin burn infection (UCBPP-PA14) and keratitis infection (39016), respectively. The ILs consisted of either 4,4-didecylmorpholinium [Dec2Mor]+ or 4-decyl-4-ethylmorpholinium [DecEtMor]+ cations combined with different anions. We found that the ILs with 4,4-didecylmorpholinium [Dec2Mor]+ cations most effectively inhibited bacterial growth as well as reduced strain fitness and virulence factor production. Our results indicate that these ILs could be used to treat P. aeruginosa infections. 相似文献
998.
999.