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251.
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AIM:To investigate the protective effect of insulin like growth factor-1 (IGF-1) against radiation-induced injury in c17.2 neural stem cells.METHODS:c17.2 neural stem cells were cultured in vitro and identified by nestin immunohistochemistry and X-gal staining.The IGF-1 adenoviral vector was transfected into c17.2 neural stem cells.The expression of IGF-1 was detected by IGF-1 immunohistochemistry.Necrosis and apoptosis of c17.2 neural stem cells were induced by radiation at doses of 4 Gy,6 Gy and were detected by flow cytometry and TUNEL test.The effect of IGF transfection on the degree of necrosis and apoptosis in these cells was also observed.RESULTS:c17.2 cells were identified by nestin and X-gal staining.Immunohistochemistry verified the expression of IGF-1 in the c17.2 neural stem cells transfected with adenoviral vector.At the same doses of radiation,the rates of apoptosis and necrosis in c17.2 neural stem cells transfected with IGF-1 were lower than those in the cells without IGF-1 adenoviral vector transfection.CONCLUSION:The rate of necrosis and apoptosis of c17.2 neural stem cells induced by radiation is decreased by transfection of IGF-1 adenoviral vector.IGF-1 shows a protective effect on c17.2 cells. 相似文献
253.
AIM: To investigate the potential of murine epidermal stem cell (ESC) differentiation after seeded in a biodegradable carrier and implanted subcutaneously into syngeneic recipient mice. METHODS: ES cells were induced in vitro to differentiate into ESCs. After stained with a fluorescent dye Hoechst 33342, these ESCs were seeded into a polyglycolic acid (PGA) net containing collagen gel, functioning as a cell carrier, and implanted subcutaneously into 129/J mice, which were syngeneic to these stem cells. RESULTS: The ESCs kept alive in the implant when observed under a fluorescent microscopy 3 weeks or longer after implantation, and could differentiate into hair follicle-like structure, glandular structure, and gave rise to additional structures displaying features resembling native dermis. No apparent rejection or severe side effects were observed at least 10 weeks post-implantation. CONCLUSION: It is feasible to use these ESCs as seed cells in the study to fabricate dermal equivalent having the potential to develop dermal appendages. 相似文献
254.
AIM:To investigate the effects of uremic serum of different molecular weight groups on gene and protein expression of connective tissue growth factor (CTGF) in human renal tubular epithelial cells.METHODS:The serum from 40 chronic renal failure patients and 20 healthy volunteers were collected and uremic serum was segregated to three groups: >10 000 D,5 000-10 000 D,<5 000 D by 10 000 D and 5 000 D molecular weight Centricon Plus 20 Centrifugal Filter Devices.The protein expression of CTGF was examined by Western blotting.The mRNA expression of CTGF was detected by RT-PCR.RESULTS:CTGF gene expression were increased in 2.5%-20% uremic serum groups compared with that in normal control group,and it was the highest in 10% uremic serum groups.CTGF gene expression was increased significantly in molecular weight >10 000 D and 5 000-10 000 D groups,and the highest was in >10 000 D group,but it was no significant difference in <5 000 D group compared with that in normal control group.CTGF protein was increased in different molecular weight uremic serum groups compared with that in normal control group,and gradually increased following the increasing of uremic serum concentration and it was the highest in molecular weight >10 000 D group.CONCLUSION:Human renal tubulointerstitial fibrosis was accelerated significantly by uremic toxin,especially molecular weight >10 000 D uremic toxin through promoting the gene and protein expression of CTGF in renal tubular epithelial cells in patients with chronic renal failure. 相似文献
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256.
ZHOU Dun-hua WEI Jing HUANG Shao-liang FANG Jian-pei BAO Rong WU Yan-feng LI Yang 《园艺学报》2006,22(8):1606-1609
AIM:To study the isolation,expansion and purification of mesenchymal stem cells (MSCs) from human umbilical cord blood (UCB),and investigate some biological identities of MSCs.METHODS:(1) MSCs of UCB,adult bone marrow (BM) and fetus BM were isolated by centrifugation with Ficoll,and the different kinds of MSCs were observed everyday.(2) Surface markers of MSCs were identified by flow cytometry.(3) The level of HGFs (TPO,SCF,FLT-3L,IL-6) secreted by different sources of MSCs was checked by ELISA method.RESULTS:(1) No difference in morphology of the colonies between UCB MSCs and BM MSCs was observed.However,the mononuclear cells needed in culture of UCB MSCs was about 3 times more than that in culture of BM MSCs.The times of UCB MSCs colony formation and confluencing were longer than that of BM in primary culture.(2) After passaged,there was no significant difference in the proliferation rates of 3 kinds of MSCs.Only 4 of 15 UCB samples contained a homogeneous population of MSCs.(3) UCB MSCs shared the same markers with BM MSCs.Neither hematopoietic marker nor immunologic recognition antigens were expressed.(4) The level of hematopoietic growth factors (HGFs) secreted by 3 kinds of MSCs was similar.CONCLUSIONS:(1) MSCs were isolated from UCB,but the amount of MSCs in UCB was smaller than that in BM,and just seldom samples of UCB contained homogeneous MSCs.(2) MSCs from UCB and BM shared the same biological characteristics,such as proliferation ability,surface markers,immunophenotypes and HGFs secretion. 相似文献
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258.
Thaís C.C. Fernandes 《Pesticide biochemistry and physiology》2007,88(3):252-259
The trifluralin is an agent that promotes a cellular damage due to its direct action on the microtubules. This action leads to a decontrol in the cellular division, bringing about polyploid cells. In this work, we show the evidences that the exceeding genetical material of theses polyploidizated cells tends to be eliminated from the nucleus in the form of micronucleus. Our analyses prove this fact, both by the presence of a number of cells carrying micronucleus, and by the evidences of the elimination of the exceeding material itself, after exposition of the Allium cepa root tips tested with several concentration of trifluralin herbicide. It was noticed that the residual concentration induced a number of polyploid cells, micronuclei and mini cells. Inferences about the implications of the elimination of genetic material from micronuclei, such as cell viability and apoptosis, are also presented. 相似文献
259.
将传染性支气管炎病毒(IBV)ZJ971 S1基因亚克隆到绿色荧光蛋白(GFP)表达载体pEGFP—C2中,成功构建重组表达质粒pEGFP—ZJ971-S1。重组质粒在脂质体的介导下转染Vero细胞,借助荧光显微镜在转染后4h观察到S1—GFP融合蛋白的瞬时表达。免疫细胞化学染色(ICC)结果显示,抗ZJ971 S1D蛋白单克隆抗体和鸡抗IBVZJ971全病毒血清特异性识别了S1基因转染细胞,表明S1蛋白在Vero细胞中得到有效表达。荧光显微镜观察和ICC均表明,S1表达蛋白主要分布在转染细胞的胞浆内,而胞核中未见分布,提示IBVS1蛋白内可能存在与病毒装配相关的细胞定位信号。 相似文献
260.
几种黏膜免疫佐剂对鸡小肠IgA分泌细胞的影响 总被引:8,自引:2,他引:8
分别在新城疫Ⅳ系弱毒苗中添加黏膜免疫佐剂乳酸杆菌、CpG DNA、重组IL-2、氟化钠和大豆黄酮,经口免疫鸡后,研究十二指肠、空肠、Peyer’s斑单位面积IgA分泌细胞的变化。首先提纯鸡IgA和制备兔抗鸡IgA血清,然后应用免疫组化技术显示鸡小肠IgA分泌细胞。结果表明,在免疫后第3周、第5周乳酸杆菌组比新城疫组(ND)极显著增加各段小肠IgA分泌细胞的数量(P〈0.01);CpGDNA、重组IL-2和大豆黄酮在整个免疫期内均明显增加鸡小肠黏膜局部IgA分泌细胞数量;NaF对鸡体黏膜局部IgA分泌细胞数量无明显增加。结果表明乳酸杆菌、CpGDNA、重组IL-2和大豆黄酮是有效的口服黏膜免疫佐剂。 相似文献