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排序方式: 共有157条查询结果,搜索用时 31 毫秒
1.
通过对小麦新品种豫麦1O号的观察,认为该品种在上蔡县增产潜力较大。为充分发挥其增产优势,从整地播种,施肥浇水,中、后期管理等方面提出了措施和建议。  相似文献   
2.
AN Xiao-hui  CAI Guo-ping 《园艺学报》2003,19(11):1449-1452
AIM: To confirm the existence of the endothelial progenitor cells in human cord blood and to study its differentiation and development process. METHODS: The mononuclear cells in human cord blood were isolated using lymphocyte separation solution. Then the mononuclear cells were cltured in MCDB131 containing 20% fetal bovine serum. The effects of 5 μmol/L dexamethasone, the extract from bovine brain, insulin and hypoxanine on the proliferation and differentiation of the adherent cells were observed. The morphology of the adherent cells were examined twice daily by inverted phase contrast microscope. CD34 and CD14 expression were determined by FACS. Immunohistochemistry was used to confirm the expression of factor Ⅷ. RESULTS: The proliferative endothelial progenitor cells existed within the CD34-adherent mononuclear cells of human cord blood. Dexamethasone and hypoxanine decreased the number of spindle-shaped cells and caudated cells. Bovine brain extract, insulin and FCS enhanced the number of spindle-shaped cells and caudated cells. CONCLUSION: The existence of endothelial progenitor cells within the CD34 - adherent monouclear cells of the human cord blood was observed and these cells were able to differentiate into endothelial-like cells in vitro.  相似文献   
3.
AIM: To explore the ex vivo expansion characteristics of the endothelial progenitor cells (EPCs). METHODS: CD34+ cells were selected from umbilical cord blood mononuclear cells (MNC) by MiniMACS system, expanded at the same conditions as that for total MNC, coincubation of CD34+ and CD34- from the same donation for EPCs. In addition, we tested the effect of vessel endothelial growth factor (VEGF) and passage on cell differentiation, expansion kinetics and apoptosis. EPCs were determined and quantified by immunocytochemistry and flow cytometry. RESULTS: Coculture of CD34+ and CD34-,total MNC led to a significant increase in the expansion of CD34+ cells compared with CD34 enrichment (P<0.05). There was a trend toward decreased apoptosis in cultures when early passage was performed once the linear cord like structures appeared. There was no significant effect on apoptosis between with VEGF and without VEGF group (P>0.05). These differentiated EPCs were stained positive for CD34+, von Willebrand factor (vWF), KDR, CD31 and incorporate acetylated low-density lipoprotein (LDL). CD34+ and AC133+cells accounted for 68.2%±6.3% (n=6) and 57.2%±9.8% (n=6) of attaching (AT) cells at day 7 of culture, respectively. CONCLUSIONS: Coculture of CD34+ and CD34- or culture of MNC enhances ex vivo expansion of EPCs. Early passage decreases apoptosis rate, VEGF has no significant effect on ex vivo expansion of EPCs.  相似文献   
4.
AIM: To investigate the anti-metastasis effect of weimaining, extracted from fragopyrum cymosum meissn, a Chinese medicine, on murine Lewis lung carcinoma (3LL). METHODS: The anti-metastasis effect of weimaining in vivo was detected in the grafting lung metastasis model of murine Lewis lung carcinoma. The effects of the drug on the expression of CD34 and E-cadherin were investigated by immunohistochemical staining and RT-PCR. RESULTS: Weimaining effectively inhibited the lung metastasis of 3LL at a concentration of 250 mg·kg-1·d-1, significantly suppressed the expression of CD34 and increased the expression levels of E-cadherin protein and mRNA in 3LL cells. CONCLUSIONS: Weimaining inhibits the metastasis of murine Lewis lung carcinoma (3LL) in vivo via increasing the expression of E-cadherin and decreasing microvessel density of tumor tissue.  相似文献   
5.
AIM: To explore the feasibility and biological characterization of long-term regulated expansion of JAK2 transduced human CD34+ cord blood cells in vitro.METHODS: A retrovirus (RV) vector which contains JAK2 catalytic domain and two binding sites for a chemical inducer,dimerization (AP20187),was cloned (designated MGI-F2JAK2).CD34+cells were enriched from cord blood with a MiniMACS system.The purified CD34+ cells were transfected with supernatant from the retrovirus packaging cell line that expressed JAK2.Following transduction,cells were expanded into four groups: AP20187 alone,FL alone,TPO,alone,AP20187+FL+TPO,respectively.The expanded cells were monitored by GFP expression,immunophenotyping,progenitor colony assay,karyotype analysis as well as tumorigenesis in nude mice.RESULTS: The purity of selected CD34+ cells was over 91% and gene transfer rate was 49.32%±6.21%.Only the group of AP20187 +FL+ TPO was obtained a significant sustained outgrowth of the transduced CD34+ cord blood cells.The percentage of GFP+ cells consistently produced a rise to the 90% peak level by the end of 8th week of culture.Flow cytometry analysis showed that the phenotype of the expanded cells was CD33+,CD61+ and Gly-A+ partial positive;CD38+ and HLA-DR+ strong positive,while CD2,CD7 and CD19 were almost negative.Colony assays performed in methycelluos,which can give rise to BFU-E,CFU-GM and CFU-Mix,the CFU-GM was predominantly in all colonies.The tumor was not observed in nude mice and the karyotype analysis was normal from expanded cells.CONCLUSION: The results demonstrate that AP20187-mediated activation of JAK2 signaling is capable of stimulating expansion JAK2 transduced CB CD34+ cells in combination with FL and TPO.This system may have applications for studies in signaling transduction,hematopoiesis,and for gene and cell therapy.  相似文献   
6.
AIM: Humanized-NOD/SCID(hu-NOD/SCID) mouse model was established and the level of immune reconstitution was assessed in this model. METHODS: Mononuclear cells (MNC) and CD34+ cells were isolated or sorted from cord blood(CB). Human CD45, CD19, CD3 markers on cells from NOD/SCID murine peripheral blood(PB), bone marrow(BM), thymus were detected by FCM from 4 to 10 weeks after hematopoietic stem cell transplantation. After 10 weeks, the gene expressions of the human β2M and RAG2 were detected by RT-PCR in PB or bone marrow of mice model. RESULTS: Human CD45, CD19, CD3 cells populations in PB and BM were found by flow cytometry in mice model transplanted with CD34+ cells or CB MNC from 4 to 10 weeks. The highest positivity of human lymphocytes was at 8 week after transplantation. The levels of human cell engraftment in mice transplanted with CD34+ cells were higher than those in mice transplanted with CB MNC. The mRNA of human β2M and RAG2 were found by RT-PCR in BM.CONCLUSION: The higher level of human lymphocyte engraftment is established in NOD/SCID mouse model transplanted with CD34+ compared with CB MNC. The maturation of T lymphocytes could be happened in bone marrow of mice model.  相似文献   
7.
论述了疱疹病毒UL34基因的序列特点、编码蛋白结构特点、基本功能以及它与UL31蛋白、Us3蛋白、动力蛋白、核纤层蛋白的相互作用。表明,UL34基因对病毒的早期包装、成熟和出芽以及对UL31蛋白和核纤层蛋白在感染细胞中的正确定位都具有重要作用。  相似文献   
8.
宁夏小麦品种慢锈基因Lr34/Yr18的分子检测   总被引:1,自引:0,他引:1  
Lr34/Yr18是重要的小麦慢叶锈/慢条锈基因,可用于小麦锈病抗性改良。为了明确Lr34/Yr18基因在宁夏小麦中的分布特点,利用STS标记csLV34对111份宁夏小麦品种中慢锈基因Lr34/Yr18的等位变异进行了分子检测,并且进行了成株期条锈病抗性鉴定。结果表明,20份材料携带Lr34/Yr18基因,占18.0%。不同来源的小麦品种中Lr34/Yr18基因分布频率不同,农家品种中分布频率最高,占90.9%;引进品种中所占比例为14.3%;育成品种中所占比例最低,仅占7.7%。含有Lr34/Yr18基因的品种对条锈病具有较好的抗性,可作为今后宁夏小麦抗锈病育种的重要抗源。  相似文献   
9.
苏玉34(原名DJ703)江苏省大华种业集团有限公司以D5835为母本,D124为父本组配的玉米单交种,于2007年育成,2012年通过江苏省农作物品种审定委员会审定。该品种夏播全生育期96d左右,株高220~250cm,穗位高90~100cm,穗长18~20cm。穗行数16左右,多年多点试验示范结果表明,该品种具有高产、稳产、抗病抗倒能力强,是一个综合性状优良的玉米新品种。  相似文献   
10.
为了探讨新型广谱乳酸菌细菌素格氏乳球菌素LG34在乳品中的应用效果,研究乳品主要成分及乳品添加剂对格氏乳球菌素LG34抑菌活性的影响。采用琼脂扩散法,以格氏乳球菌素LG34为空白对照组,以添加乳品主要成分及添加剂的格氏乳球菌素LG34为实验组。结果表明:乳品主要成分乳糖、干酪素、乳脂肪显著降低了格氏乳球菌素LG34的抑菌活性;乳品添加剂六偏磷酸钠显著降低了格氏乳球菌素LG34的抑菌活性,羧甲基纤维素钠显著提高了格氏乳球菌素LG34的抑菌活性。  相似文献   
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