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981.
AIM:To investigate the inhibitory effect of oxymatrine (OM) on high glucose-induced rat renal tubular epithelial-mesenchymal transition (EMT). METHODS:The rat renal tubular epithelial NRK52E cells were cultured in vitro. The cells were divided into control group, high glucose group, high glucose+different concentrations of OM groups and high glucose+0.50 g/L OM dynamic observation group. The expression of TGF-β1, Smad7, α-SMA and E-cadherin at mRNA and protein levels was detected by real-time PCR and Western blotting. The viability of NRK52E cells was determined by MTT assay. RESULTS:(1) Compared with control group, the expression of TGF-β1 and α-SMA at mRNA and protein levels in high glucose group gradually increased, and Smad7 protein and E-cadherin mRNA and protein gradually reduced, but the mRNA expression of Smad7 gradually increased. (2) Compared with high glucose group, as increases in OM doses, the expression of TGF-β1 and α-SMA at mRNA and protein levels in high glucose+different concentrations of OM groups gradually reduced, and Smad7 protein and E-cadherin mRNA and protein gradually increased, but the mRNA expression of Smad7 had no significant change. (3) Compared with high glucose group, the expression of TGF-β1 and α-SMA at mRNA and protein levels was significantly reduced, the expression of E-cadherin at mRNA and protein levels significantly increased, and the protein expression of Smad7 significantly increased, but the mRNA expression of Smad7 had no significant change in high glucose+0.50 g/L OM dynamic observation group. CONCLUSION: In NRK52E cells, oxymatrine inhibits high glucose induced EMT by down-regulating TGF-β1 and up-regulating Smad7, thus preventing the fibrosis effect of TGF-β1/Smads signaling. 相似文献
982.
CHEN Jin-ming GAN Jian-xin YU Chun-zhao WANG Shen-hua WU Jun-song YI Jian-hua YANG Jian-xin ZHOU Hai-bo 《园艺学报》2006,22(9):1766-1770
AIM:To evaluate the relationship between RUNX3,cyclin E,P21,biological features and survival in gastric cancer patients.METHODS:RUNX3 was examined using immunohistochemical staining.Cyclin E and P21 were analyzed by flow cytometry.Survival was evaluated by Kaplan-Meier survival curves.RESULTS:The positive-expression rate of RUNX3,cyclin E and P21 in tumor tissue from 56 patients with gastric cancer were 44.6%,64.3% and 32.1%,respectively.RUNX3 expression was correlated with lymph node metastasis and distant metastasis (P<0.05).Cyclin E might be related to depth of invasion,lymph node metastasis and distant metastasis (P<0.05).P21 was correlated with lymph node metastasis (P<0.05).It was revealed that RUNX3 and P21 were correlated (r=0.57,P<0.05),no correlation between RUNX3 and cyclin E was observed (r=0.25,P>0.05).Using Kaplan-Meier survival curves and the Log-rank test,there was correlation between RUNX3,cyclin E and survival (P<0.05).No correlation between P21 and survival was observed (P>0.05).CONCLUSION:RUNX3 may be related with tumorigenesis and tumor progression by affecting P21 expression.The detection of RUNX3 and cyclin E may be helpful in evaluating the clinicopathological parameters and prognosis in gastric carcinoma patients. 相似文献
983.
984.
番木瓜eIF(iso)4E基因克隆及其结构和表达分析 总被引:1,自引:0,他引:1
eIF4E ( eukaryotic translation initiation factor 4E) 家族基因在多种病毒侵染植物过程中起重要作用。应用RT-PCR和RACE方法在番木瓜中克隆了cDNA全长为995 bp的eIF4E异构体基因, 命名为CP-eIF(iso)4E(GenBank登录号为FJ595992) 。其编码的蛋白含有206个氨基酸, 蛋白一级结构中的活性部位位点高度保守, 三维结构中可能的抗性位点位于帽结合区域( cap-binding pocket) 表面。半定量RT-PCR结果表明, CP-eIF ( iso) 4E在番木瓜叶片中表达较弱, 在花瓣中表达最强。 相似文献
985.
以金边虎尾兰为试材,研究了IAA、NAA、6-KT和B9等植物生长调节剂对叶段进行预处理后(处理时间3 h)的扦插效应.结果表明:不同植物生长调节剂对金边虎尾兰叶段生根的影响不同,同一植物生长调节剂的浓度不同,对生根效果的影响也不同.其中,IAA以300mg/L效果最好;NAA以400 mg/L效果最好;6-KT以35 mg/L效果最好;B9以600mg/L效果最好. 相似文献
986.
AIM:To investigate the role of apolipoprotein E(ApoE) in cholesterol efflux mediated by ATP-binding cassette transporter A1(ABCA1) and ATP-binding cassette transporter G1(ABCG1). METHODS:RAW 264.7 cells were seeded in either 6-well or 24-well plates, and then incubated with 20 mg/L low-density lipoprotein receptor gene knockout(LDLr-/-) mouse lipoprotein 20 mg/L ApoE gene knockout(ApoE-/-) mouse lipoprotein or culture medium alone. The changes of intracellular lipid content were measured by transmission electron microscopy and enzymatic colorimetric method. The cholesterol efflux was determined by liquid scintillation. The mRNA and protein levels of ABCA1 and ABCG1 were detected by real-time PCR and Western blotting, respectively. RESULTS:The ApoE-/- mouse lipoprotein increased the content of intracellular cholesterol ester by 60% compared with the control cells. In addition, ApoE-/- mouse lipoprotein treatment decreased the cholesterol efflux to apolipoprotein A-I(ApoA-I) and high-density lipoprotein(HDL) compared with LDLr-/- mouse lipoprotein treatment. ApoE-/- mouse lipoprotein treatment inhibited the mRNA and protein levels of ABCA1 and ABCG1 compared with LDLr-/- mouse lipoprotein treatment. CONCLUSION:Apolipoprotein E plays an important role in the cholesterol efflux of macrophages, which is associated with its regulatory effect on the expression of ABCA1 and ABCG1. 相似文献
987.
AIM: To determine whether interleukin 4 and interleukin 4 receptor α chain are associated with allergic asthma in children and to study the impact of such polymorphism upon plasma IgE.METHODS: Two polymorphism sites of IL-4 and IL-4R were studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).RESULTS: (1)The results showed that the IL-4 promoter -589 was not associated with children allergic asthma, however, the IL-4R α chain 576RR genotype and R allele were significantly increased in the subjects with asthma in children compared with age-matched control subjects (χ2=11.84, P<0.01; χ2=13.03, P<0.01). The IL-4R α chain 576RR genotype was associated with higher plasma IgE. CONCLUSION: These date suggest that the IL-4R α chain R576 is a risk factor of allergic asthma in children in Chinese, and is also related with higher plasma IgE level. 相似文献
988.
AIM: To study the molecular mechanisms of cellular repressor of E1A-stimulated genes (CREG) on the proliferation of human vascular smooth muscle cells (VSMCs) in vitro.METHODS: The pLNCX2-CREG plasmid and the pSM2-siCREG plasmid were transfected into VSMCs to produce the cell clones of over-expression and down-expression of CREG, respectively.BrdU assay and FACS cell cycle analysis were performed to detect the proliferation of the cells.The expression and localization of insulin-like growth factor Ⅱ receptor(IGF2R) in the hVSMCs were detected by Western blotting and immunocytochemistry.The expression and secretion of insulin-like growth factor Ⅱ(IGFII) were measured by RT-PCR and ELISA.Alexa 488-labeled rhIGFII was used to investigate the endocysis of the cells.The blockade of IGFII internalization was conducted by treating the cells with both neutralized antibody of IGF2R and recombinant IGF2R peptide to detect the effect of IGFII on HVSMCs growth.Furthermore, Western blotting and signal pathway inhibitor were used to analysis the activation of PI3K/Akt and ERK on VSMCs proliferation.RESULTS: Compared with the control cells, Western blotting identified that the expression of CREG was increased in VSMCs-CREG cells and was decreased in VSMCs-siCREG cells.Meanwhile, the over-expression of CREG in the cells inhibited the proliferation of VSMCs and enhanced the distribution of IGF2R in cellular membrane.Furthermore, over-expression of CREG also accelerated the endocytosis of IGFII in VSMCs-CREG cells, and attenuated the secretion of IGFII into cell medium.Blockade experiments showed that enhancement of IGFII secretion promoted the proliferation of HVSMCs.PI3K/Akt and ERK signal pathways mediated the effect of IGFII on the VSMCs.CONCLUSION: CREG inhibits the proliferation of VSMCs through interfering with the internalization of IGF2R-IGFII. 相似文献
989.
I. Valpotic M. Frankovic I. Vrbanac 《Comparative immunology, microbiology and infectious diseases》1992,15(4):271-279
We attempted to determine F4(K88)-adhesive and non-adhesive phenotypes of infant (neonatal <3 day old and weaned <4 week old pigs) and adult (>6 month old) swine by ELISA using immobilized F4(K88)ac fimbrial antigen or whole F4(K88) + E. coli cells (strains M1823 and 1476) and isolated small intestinal brush borders or easily-obtainable fecal samples from the same animals. Nineteen of 22 neonates (86%), 17 of 20 weaners (85%), and 26 of 39 adults (67%) were classified identically as F4(K88) receptor-positive or negative by the ELISA. The ELISA with feces from adult swine was found to be almost equally specific (87%) as that with feces from neonatal (90%) and weaned (91%) pigs. However, the sensitivity of the assay was low (38%), indicating that fecal samples from adults contained less receptor-material than necessary for comparable phenotyping. The receptor-positive brush borders from neonates and weaners reacted significantly better (P < 0.02, < 0.001 respectively) with purified F4(K88) antigen than did those from adults. There was good agreement between the average ELISA values for feces from infant and adult swine regardless the source of coating antigen applied. With this assay we can determine F4(K88) phenotypes of infant swine using easily-collected fecal samples rather than isolated brush borders. It was also concluded that tested feces is not an acceptable alternate source of the receptor-material to brush borders from F4(K88)-susceptible adult swine. 相似文献
990.
Rose N Lunazzi A Dorenlor V Merbah T Eono F Eloit M Madec F Pavio N 《Comparative immunology, microbiology and infectious diseases》2011,34(5):419-427
The importance of the domestic pig reservoir for Hepatitis E virus (HEV) was assessed by estimating the seroprevalence and prevalence of HEV contaminated livers in French slaughter-aged pigs. 6565 sera and 3715 livers were randomly sampled from 186 pig farms throughout the country. Taking the sampling design into account, the farm-level seroprevalence was 65% (95% CI 57–74) and 31% (95% CI 24–38) of the slaughter-aged pigs had antibodies against HEV. The individual prevalence of HEV RNA positive livers was 4% (95% CI 2–6) and 24% (95% CI 17–31) of the farms had at least 1 positive liver. Most isolates were of genotype 3f (76.7%) with smaller amounts of 3c (18.6%) and 3e (4.6%). The high prevalence of HEV in pigs and the similarities between HEV subtypes from pigs and humans corroborates the possible zoonotic origin of some HEV autochthonous infections. 相似文献