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991.
Nina Safar-Hermann Mohammed N. Ismail Han Sun Choi Erich Mstl Elmar Bamberg 《Zoo biology》1987,6(2):189-193
Estrogen concentration in feces was investigated in five different herbivorous species of zoo animals. Using a nonspecific estrogen radioimmunoassay, in four species (red buffalo, yak, Grevy's zebra, and Nubian ibex) pregnancy was revealed by measuring estrogen concentration in feces. In hippopotamus, the levels of fecal estrogens were not different between pregnant and nonpregnant animals. 相似文献
992.
利用南京地区夏季炎热的自然条件,连续两年在高温季节(7—8月)进行实验。第一年(系列Ⅰ)的实验动物为四头装置瘤胃瘘管的空怀母水牛,研究高温初期(27.5~33.4℃)和持续高温期(28.0~35℃)对水牛瘤胃消化代谢的影响。第二年实验(系列Ⅱ)利用三头装置瘤胃瘘管的海仔母水牛重复高温(26~35.3℃)实验。 夏季高温期间,实验水牛的呼吸率、瘤胃温度和直肠温度升高,采食量减少,饮水量增加,瘤胃液流速减缓。高温初期出现瘤胃代谢升高[总挥发性脂肪酸(TVFA)和氨氮(NH_3-N)浓度及乙酸/丙酸(A/P)比率升高]。但在持续高温情况下,水牛的采食和瘤胃代谢均明显抑制。采取瘤胃内降温措施(投入冰袋)或冷水淋浴,均能迅速降低呼吸率、直肠和瘤胃温度,恢复采食和反刍,并缓解瘤胃代谢的抑制。提示动物机体参与调节瘤胃代谢的变化,并为改善水牛夏季的饲养管理提供生理学依据。 相似文献
993.
The advent of next generation sequencing technologies allows one to discover nearly all rare variants in a genomic region of interest. This technological development increases the need for an effective statistical method for testing the aggregated effect of rare variants in a gene on disease susceptibility. The idea behind this approach is that if a certain gene is involved in a disease, many rare variants within the gene will disrupt the function of the gene and are associated with the disease. In this article, we present the rare variant weighted aggregate statistic (RWAS), a method that groups rare variants and computes a weighted sum of differences between case and control mutation counts. We show that our method outperforms the groupwise association test of Madsen and Browning in the disease-risk model that assumes that each variant makes an equally small contribution to disease risk. In addition, we can incorporate prior information into our method of which variants are likely causal. By using simulated data and real mutation screening data of the susceptibility gene for ataxia telangiectasia, we demonstrate that prior information has a substantial influence on the statistical power of association studies. Our method is publicly available at http://genetics.cs.ucla.edu/rarevariants. 相似文献
994.
995.
Previously, we demonstrated that the gastrin releasing peptide (GRP) induces cyclooxygenase-2 (COX-2) expression through a Rho-dependent, protein kinase C (PKC)-independent signaling pathway in fibroblasts (Slice et al., 1999, J Biol Chem 274:27562-27566). However, the specific role of heterotrimeric guanine nucleotide binding regulatory proteins (G-proteins) that are coupled to the GRP receptor in Rho-dependent COX-2 expression has not been elucidated. In this report, we utilize embryonic fibroblasts from transgenic mice containing double gene knock-outs (DKO) for Galpha(q/11) and Galpha(12/13) to demonstrate that COX-2 promoter activation by GRP requires Galpha(q). Furthermore, we show that GRP-dependent COX-2 gene expression, as assessed by a COX-2 reporter luciferase assay, was induced in cells lacking Galpha(12/13) but was blocked in cells that did not express Galpha(q/11). GRP-dependent COX-2 promoter induction in Galpha(q/11) deficient cells was rescued by expression of wild type Galpha(q) but blocked by inhibition of calcium signaling in calcium-free media or in cells treated with 2-aminoethoxydiphenylborate (2-APB). Co-stimulation of transfected Galpha(q/11) deficient cells with GRP and thapsigargin (TG) induced the COX-2 promoter. Activation of endogenous Rho by expression of Onco-lbc or expression of Rho A Q63L resulted in COX-2 promoter activation in Galpha(q/11) deficient cells. Inhibition of Rho by Clostridium botulinum C3 toxin blocked COX-2 promoter induction. Expression of Galpha(q) Q209L in the well-characterized fibroblast cell line, NIH3T3, induced the COX-2 promoter which was blocked by expression of C3 toxin. These results demonstrate that calcium signaling mediated by Galpha(q) and Rho play critical roles in GRP-dependent COX-2 expression in fibroblasts. 相似文献
996.
The regulation of insulin on depression and depression‐like behaviour has been widely reported. Insulin and activation of its receptor can promote learning and memory, affect the hypothalamic‐pituitary‐adrenal axis (HPA) balance, regulate the secretion of neurotrophic factors and neurotransmitters, interact with gastrointestinal microbiome, exert neuroprotective effects and have an impact on depression. However, the role of insulin on depression remains largely unclear. Therefore, in this review, we summarized the potential role of insulin on depression. It may provide new insight for clarifying role of insulin on the pathogenesis of depression. 相似文献
997.
998.
Jianhui Wu Shengjie Liu Qilin Wang Qingdong Zeng Jingmei Mu Shuo Huang Shizhou Yu Dejun Han Zhensheng Kang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(1):43-58
Key message
High-throughput SNP array analysis of pooled extreme phenotypes in a segregating population by KASP marker genotyping permitted rapid, cost-effective location of a stripe rust resistance QTL in wheat.Abstract
German wheat cultivar “Friedrichswerther” has exhibited high levels of adult plant resistance (APR) to stripe rust in field environments for many years. F2:3 lines and F6 recombinant inbred line (RILs) populations derived from a cross between Friedrichswerther and susceptible landrace Mingxian 169 were evaluated in the field in 2013, 2016 and 2017. Illumina 90K iSelect SNP arrays were used to genotype bulked extreme pools and parents; 286 of 1135 polymorphic SNPs were identified on chromosome 6B. Kompetitive Allele-Specific PCR (KASP) markers were used to verify the chromosome region associated with the resistance locus. A linkage map was constructed with 18 KASP-SNP markers, and a major effect QTL was identified within a 1.4 cM interval flanked by KASP markers IWB71602 and IWB55937 in the region 6BL3-0-0.36. The QTL, named QYr.nwafu-6BL, was stable across environments, and explained average 54.4 and 47.8% of the total phenotypic variation in F2:3 lines and F6 RILs, respectively. On the basis of marker genotypes, pedigree analysis and relative genetic distance QYr.nwafu-6BL is likely to be a new APR QTL. Combined high-throughput SNP array genotyping of pooled extremes and validation by KASP assays lowers sequencing costs compared to genome-wide association studies with SNP arrays, and more importantly, permits rapid isolation of major effect QTL in hexaploid wheat as well as improving accuracy of mapping in the QTL region. QYr.nwafu-6BL with flanking KASP markers developed and verified in a subset of 236 diverse lines can be used in marker-assisted selection to improve stripe rust resistance in breeding programs.999.
Jun Ho Hong In Wook Hwang Myung Ho Lim Ho Jang Kwon Han Jun Jin 《Genes & genomics.》2018,40(12):1309-1317
It is well known that dopaminergic genes affect the development of attention deficit hyperactivity disorder (ADHD) in various populations. Many studies have shown that variable number tandem repeats (VNTRs) located within the 3′-untranslated region of DAT1 and in exon 3 of DRD4 are associated with ADHD development; however, these results were inconsistent. Therefore, we investigated the genetic association between two VNTRs and ADHD in Korean children. We determined the VNTRs using PCR. We examined genotype and allele frequency differences between the experimental and control groups, along with the odds ratios, using Chi square and exact tests. We observed a significant association between the children with ADHD and the control group in the 10R/10R genotype of DAT1 VNTRs (p?=?0.025). In addition, the 11R allele of DAT1 VNTRs showed a higher frequency in the control group than in the ADHD group (p?=?0.023). Also, the short repeat (without 11R) and long repeat alleles (including 11R) were associated with ADHD (p?<?0.05). The analysis of DRD4 VNTRs revealed that the 2R allele is associated with ADHD (p?=?0.025). A significant result was also observed in long and short repeats (p?<?0.05). Additionally, ADHD subtypes showed that the DRD4 VNTRs are associated with combined and hyperactive-impulsive subtype groups (p?<?0.05). Therefore, our results suggest that DAT1 VNTRs and DRD4 VNTRs play a role in the genetic etiology of ADHD in Korean children. 相似文献
1000.