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941.
Zabihollah Zamani Ali Shahi-Gharahlar Reza Fatahi Naser Bouzari 《Plant Systematics and Evolution》2012,298(2):499-509
Subgenus Cerasus species are useful genetic resources for cherry breeding programs. A total of 17 morphological traits together with 19 random
amplified polymorphic DNA (RAPD) primers were used to study 39 accessions including 34 wild Cerasus subgenus genotypes belonging to Prunus avium L., P. cerasus L., P. mahaleb L., P. microcarpa Boiss., P. incana Pall., and P. brachypetala Boiss. species, along with an unknown wild Cerasus sample, two advanced cherry cultivars (‘Lambert’ and ‘Bulgar’), and two rootstocks (‘Colt’ and ‘Gisela 6’). Genotypes were
separated into different groups according to their species and collection sites using cluster analysis performed by Ward’s
clustering method based on morphological data. Nineteen RAPD primers from 60 screened produced 304 polymorphic reproducible
bands (98.15% polymorphism). According to the similarity matrix, the lowest similarity was obtained between P. avium and P. microcarpa samples. A dendrogram was prepared by the unweighted pair-group method with arithmetic average (UPGMA), and the accessions
were separated according to their species and geographic origin. In both morphological and molecular results, the advanced
cultivars and rootstocks were separated from wild genotypes, and the unknown genotype was grouped with P. mahaleb accessions. Grouping by morphological characteristics was compared with the results of RAPD analysis, with no significant
correlations between morphological and molecular data being found. This is the first report of molecular (RAPD) genetic diversity
study in wild Cerasus subgenus genotypes from Iran, and the results demonstrate the high potential of RAPD analysis for discrimination of Cerasus subgenus genotypes. 相似文献
942.
The complete mitochondrial genomes of five tiger samples from three subspecies (P. t. sumatrae, P. t. altica, and P. t. tigris) were successfully obtained by using 26 specifically designed Panthera-specific primer sets. The genome organization and gene arrangement of the five tiger samples were similar to each other;
however polymorphic tandem repeat sequences were observed in the control region (CR). This led to a difference in the genome
lengths obtained from these five samples with an average size of 16,994 bp for the five tiger mitochondrial genomes. The nucleotide
base composition was on average as follows: A, 31.8%; T, 27.0%; C, 26.6%; G, 14.6% and exhibited compositional asymmetry.
Most of tiger mitochondrial genome characteristics are similar to those of other common vertebrate species; however, some
distinctive features were observed in the CR. First, the repetitive sequence 2 (RS 2) contained two repeat units of 80 bp
and the first 15 bp of what would be the third repeat motif. The repetitive sequence 3 (RS 3) contained 47–50 repeat motifs
of a shorter 8 bp (ACGTAYAC)n. Second, length heteroplasmy polycystosine (poly-C) stretches was observed at the end of the HV I locus in all tiger samples. 相似文献
943.
Park SM Yan BC Park JH Choi JH Yoo KY Lee CH Baek YY Kim YM Kang IJ Won MH 《Cellular and molecular neurobiology》2012,32(3):423-434
Tetanus toxin (TeT), an exotoxin, has been studied to cause tetanus in mammalian brains, and it can block the release of some
neurotransmitters and affect seizure propagation. In the present study, we investigated neuronal damage/death and glial changes
in the mouse hippocampus after systemic administration (intraperitoneal injection) of TeT 10 and 100 ng/kg. In both the 10
and 100 ng/kg TeT-treated groups, no neuronal death occurred in any subregions of the mouse hippocampus until 24 h post-treatment;
however, there were changes in glia in the hippocampus depending on time course and dosage. The morphology of GFAP-immunoreactive
astrocytes and Iba-1-immunoreactive microglia was apparently changed in the 100 ng/kg TeT treated-group compared to the 10 ng/kg
TeT treated-group. In the 100 ng/kg TeT treated-group, they were increased in size and their immunoreactivity was distinctively
increased from 12 h post-treatment. We also found that their protein levels were increased in the hippocampus at 12 h post-treatment
of 100 ng/kg TeT. In conclusion, these results indicate that the systemic administration of 100 ng/kg TeT induced a distinctive
microglia changes in the mouse hippocampus without any neuronal death/damage. 相似文献
944.
945.
【目的】探讨A型流感病毒PB1-F2蛋白和人类凋亡调节因子1(MOAP-1)之间的相互作用。【方法】构建pACT2-MOAP-1重组质粒,与pGBKT7-PB1-F2质粒共转化酵母AH109,检测转化菌在四缺培养基的生长情况及β半乳糖苷酶报告基因的活性;利用GST pull-down和免疫共沉淀(Co-IP)技术进一步验证PB1-F2与宿主细胞蛋白MOAP-1的相互作用;通过过表达PB1-F2和MOAP-1,检测PB1-F2对MOAP-1蛋白表达水平的影响。【结果】酵母双杂交结果表明,PB1-F2和MOAP-1可以在酵母细胞内特异性结合。GST pull-down和Co-IP实验也进一步证实了这两种蛋白的相互作用,而且PB1-F2可上调外源MOAP-1的蛋白水平。【结论】流感病毒PB1-F2与MOAP-1存在相互作用,PB1-F2可能通过与MOAP-1的相互作用参与调控细胞生长及凋亡过程。 相似文献
946.
947.
948.
Altered distribution of HMGB1 in the periodontal ligament of periostin-deficient mice subjected to Waldo’s orthodontic tooth movement 总被引:1,自引:0,他引:1
949.
950.