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91.
AIM: To evaluate the alterations in calcium metabolism of the vascular smooth muscle in the late phase of septic shock and test the hypothesis that nitric oxide might be involved in sepsis-induced vascular hyporeactivity. METHODS: Male Sprague-Dawley rats were subjected to sepsis by cecal ligation and puncture (CLP). 18 hours post CLP, rat aortic rings were employed for measurement of contractile responses by using organ bath technique. RESULTS: In endothelium-denuded aortic rings from CLP rats, concentration-contraction curves to phenylephrine (PE) and KCl were significantly decreased when compared to that from sham control rats. The transient contraction induced by PE in calcium-free Krebs solution and the concentration-dependent contraction to CaCl2 in KCl-depolarized medium were also markedly reduced. The hyporeactivity was partially reversed by treatment with aminoguanidine, a selective inducible nitric oxide synthase inhibitor. CONCLUSION: An impairment in calcium handling in vascular smooth muscle is involved in the vascular hyporeactivity during the late phase of septic shock, in which an excessive nitric oxide production might be the major mechanism. 相似文献
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AIM:To investigate the crosstalk between angiotensin Ⅱ (AngⅡ)-mediated and platelet-derived growth factor (PDGF)-mediated signal transduction in vascular smooth muscle proliferation.METHODS:A model of renal hypertension was made by two kidney/one-clip operation. Level of PDGF receptor β subunit of aorta was measured by Western Blot analysis. The effect of Ang Ⅱ on PDGF receptor β subunit expression was investigated in culture rat aortic vascular smooth muscle cells (VSMC).RESULTS:Systolic blood pressure obviously increased at 8th week after operation, whereas the level of PDGF receptor β subunit of aorta significantly increased by 126.6% (P<0.05) in 2K1C rats compared with control group. The expression of PDGF receptor β subunit in cultured VSMC stimulated by AngⅡ was higher than that of control by 192.74%(P<0.01). The effect of AngⅡ was inhibited remarkably by pretreated with losartan, a kind of specific AngⅡ receptor 1 (AT1) subtype antagonist and U73122, a kind of phospholipase C inhibitor. The effect was partly blocked by PD98059, which inhibit the activity of mitogen-activated, ERK-activating kinase (MEK).CONCLUSION:AngⅡ-induced PDGF receptor β subunit expression is regulated by the AT1 and its downstream signal molecule-PLC and ERK, might participate in the intracellular signal transduction pathway. 相似文献
94.
Asaki ABE Kazumasa OHTSUKI Yoshiki SUZUKI Takiko TAKAHASHI Yasuhiro KONDO 《Animal Science Journal》2002,73(4):309-311
The characteristics of the contraction of vascular smooth muscle were examined in thoracic aorta and ischiadic artery of chickens aged 3, 6, 10 and 18 weeks. High K+ solution induced a sustained contraction in smooth muscle preparations of aorta and ischiadic artery in vitro . The contraction of the ischiadic artery became greater with age, whereas the contraction of the aortic preparation did not. In the ischiadic artery, the magnitude of the contraction divided by the weight of the muscle preparation was constant at all ages studied. However, those in the aortic preparation decreased with age. These results suggest that the changes in the contractile responses of vascular smooth muscle owing to the age of chickens vary widely according to the preparations of blood vessels, and that the functional smooth muscle cells in the thoracic aorta of chicken do not increase with age. 相似文献
95.
AIM: To investigate the role of intracellular free Ca2+ concentration ([Ca2+]i) in the regulation of calcium-activated chloride (ClCa) channels in pulmonary artery smooth muscle cells (PASMCs) of rats under normoxic, acute and chronic hypoxic conditions. METHODS: Acute hypoxia-induced contraction was observed in rat pulmonary artery by using routine blood vascular perfusion in vitro. The fluorescence Ca2+ indicator Fura-2/AM was used to observe [Ca2+]i of rat PASMCs in normal and chronic hypoxic condition. The influences of ClCa channels on PASMCs proliferation were assessed by MTT assay. RESULTS: (1) The ClCa channel blockers niflumic acid (NFA) and indaryloxyacetic acid (IAA-94) produced inhibitory effects on acute hypoxia-evoked contractions in pulmonary artery. (2) Under chronic hypoxic condition, [Ca2+]i was increased. In normoxic condition, [Ca2+]i was (123.63±18.98) nmol/L, and in hypoxic condition, [Ca2+]i was (281.75±16.48)nmol/L (P<0.01). (3) In normoxic condition, [Ca2+]i had no significant change and no effect on ClCa channels was observed (P>0.05). (4) Chronic hypoxic increased [Ca2+]i which opened ClCa channels. The NFA and IAA-94 blocked them and decreased [Ca2+]i from (281.75±16.48)nmol/L to (117.66±15.36)nmol/L (P<0.01). (5) MTT assay showed that in chronic hypoxic condition NFA and IAA-94 decreased the value of absorbing light degree (A value) from 0.459±0.058 to 0.224±0.025 (P<0.01). CONCLUSION: Hypoxia increased [Ca2+]i which opened ClCa channels and had a positive-feedback to [Ca2+]i. This may play an important role in hypoxic pulmonary hypertension. In chronic hypoxic condition, ClCa channel may play a role in the regulation of PASMCs proliferation. 相似文献
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SHANG Dan ZHENG Qi-chang SONG Zi-fang WANG Xie-dan HU Qing-gang GUO Xing-jun 《园艺学报》2007,23(10):1887-1890
AIM: To express human Arresten gene in eukaryotic cell,and to investigate its effect on the proliferation and migration in vitro of rat primary cultured thoracic aortic vascular smooth cells (VSMCs).METHODS: COS-7 cells were transfected with recombinant eukaryotic expression plasmid pSecTag2-AT or control plasmid pSecTag2 mediated by liposome.48 hours after transfection,polymerase chain reaction (RT-PCR) was used to detect the expression of Arresten mRNA in the cells,while Western blotting assay was applied to detect expressed Arresten protein in concentrated supernatants.VSMCs were then co-cultured with the concentrated supernatants;and its proliferation was detected using cell counting kit-8 (CCK-8) in vitro.Migration of VSMCs was assayed by a microchemotaxis chamber and a polycarbonate filter (Transwell's chamber) with pores of 8 μm in diameter.RESULTS: RT-PCR revealed that the genome of Arresten-transferred cells contained a 449bp specific fragment of Arresten gene.Successful protein expression in supernatants was confirmed by Western blotting.CCK-8 assay showed that the proliferation of VSMCs was inhibited significantly by Arresten protein as compared with control group (P<0.01).Transwell's chamber showed that the number of control group,pSecTag2 transfected group and pSecTag2-AT transfected group were 28.70±3.97,26.10±4.53 and 14.00±3.33 (P<0.01).CONCLUSION: Arresten protein expressed in eukaryotic cells inhibits the proliferation and migration of VSMCs effectively in vitro. 相似文献
99.
本试验旨在体外分离培养兔子宫内膜细胞(腺上皮细胞和基质细胞)和平滑肌细胞,并且探讨纯化子宫内膜上皮细胞和基质细胞的方法。用差速离心法和差速贴壁法获得纯化的子宫内膜上皮细胞和基质细胞,用滤网法分离得到子宫平滑肌细胞,分别在添加20%胎牛血清(FBS)、100μg/mL牛胰岛素、63.5 nmol/L雌二醇(E2)、7.14nmol/L孕酮(P4)的DMEM/F12(1∶1)培养液和37℃5%CO2的饱和湿度条件下培养;用免疫组化和免疫荧光法鉴定细胞并检测分离的细胞纯度。结果表明用该方法成功地分离培养了兔子宫内膜上皮细胞和基质细胞,且2种细胞纯度都达98%左右,基质细胞出现蜕膜化;子宫平滑肌细胞的纯度为97%左右,而且出现横纹状的生长。本研究表明子宫内膜细胞和平滑肌细胞能够在体外成功培养;在含20?S、100μg/mL牛胰岛素、63.5 nmol/L E2、7.14 nmol/L P4的DMEM/F12(1∶1)培养液和37℃5%CO2饱和湿度的培养条件下最有利于体外培养的子宫内膜细胞和平滑肌细胞的生长。 相似文献
100.