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111.
Seeds of six soybean lines (Glycine max (L.) Merr. cv. Columbia, D68-127, Norredo, Sooty, T-102, Wilson 5) have been reported to lack the 120 000 dalton soybean lectin. Immunofiffusion and radioimmunoassay using anti-soybean lectin immunoglobulin failed to detect the lectin in seeds of five lines, but D68-127 seeds contained as much soybean lectin as the control line, Harosoy 63. The D68-127 seed lactin could be purified by affinity chromatography on Sepharose-N-caproylgalactosamine, and was indistinguishable from the conventional soybean lectin by the following criteria: electrophoretic migration in acidic and alkaline buffers, subunit molecular weight and composition, analytical isoelectric focusing, gel filtration chromatography.Phosphate buffered saline extracts of roots, hypocotyls, stems, and leaves of 3–66-day-old Norredo and Harosoy 63 plants lacked soybean lectin, as determined by hemagglutination and radioimmunoassay (detection limit: 1.4 μg soybean lectin/g dry weight tissue). Cotyledons of Harosoy 63 (but not Norredo) contained large quantities of the lectin, which diminished as the plants aged. 5-day-old roots and hypocotyls of 20 soybean lines did not contain soybean lectin. Roots of Columbia, Norredo, Sooty, T-102, Wilson 5, and Harosoy 63 (control) were modulated by a variety of strains of Rhizobium japonicum and Rhizobium sp.  相似文献   
112.
Immunological biomarkers that reflect the effects of exposure to environmental contaminants in coastal marine habitats were sought in European flounder (Platichthys flesus) from five locations in the German Bight with different anthropogenic impacts. During a 2-year period of sampling, innate immune responses were monitored from a total of 331 individual flounder of a body length of 18 to 25 cm. From the fish, plasma lysozyme, phagocytosis and respiratory burst activity of head kidney leucocytes were analysed and implemented as part of an integrated biological effects monitoring programme. As the measurements of the parameters applied here varied within wide ranges at some locations, spatial differences could not always be established, but some general trends could be drawn: plasma lysozyme activity was decreased in flounder contaminated with DDT adducts and some PCBs, while cellular functions such as phagocytosis and respiratory burst were stimulated by some chlorinated hydrocarbons. Correlation analysis also revealed connections not only between the parameters applied here and some contaminants but also with some biochemical parameters used as biomarkers in pollution monitoring: in flounder with decreased integrity of hepatocyte lysosomal membranes, immune functions also were impaired, and plasma lysozyme as well as phagocytosis activity of head kidney cells were impaired when the activity of cytochrome P450 1A was induced. The data presented here indicate that innate immune responses may be useful parameters to monitor cellular functions in a battery of biomarkers of different levels of biological organisation. Communicated by H. v. Westernhagen, A. Diamant  相似文献   
113.
目的:评价不同剂量甲强龙对行胸腔镜肺癌根治术患者免疫功能的影响。方法:选择择期行胸腔镜肺癌根治术患者40例,美国麻醉医师学会(American Society of Anesthesiology,ASA)Ⅱ~Ⅲ级,性别不限,年龄65~85岁,采用随机数字表法分为两组(n=20):甲强龙高剂量组(M组)和甲强龙低剂量组(C组)。在麻醉诱导前30 min,M组静脉注射甲强龙1 mg·kg-1,C组静脉注射甲强龙0.5 mg·kg-1。于诱导前(T0)、术毕(T1)、术后24 h(T2)抽取外周静脉血样,采用流式细胞术测定T淋巴细胞亚群CD3~+、CD4~+、CD8~+水平,计算CD4~+/CD8~+比值。结果:与T0时比较,M组T1和T2时CD3~+水平显著降低(P0.05),CD4~+水平、CD4~+/CD8~+比值有所降低,CD8~+水平有所升高,但是差异无统计学意义(P0.05);C组T1和T2时CD3~+、CD4~+、CD8~+水平以及CD4~+/CD8~+比值差异无统计学意义(P0.05)。与C组比较,M组T1和T2时CD3~+水平降低,T2时CD8~+水平显著升高(P0.05)。结论:麻醉诱导前30min静脉注射1 mg·kg~(-1)的甲强龙对行胸腔镜肺癌根治术患者的免疫功能有一定影响,而麻醉诱导前30 min静脉注射0.5 mg·kg~(-1)的甲强龙对患者的免疫功能无明显影响。  相似文献   
114.
Interleukin-31, produced mainly by activated CD4+ T cells, is a newly discovered member of the gp130/IL-6 cytokine family. Unlike all the other family members, IL-31 does not engage gp130. Its receptor heterodimer consists of a unique gp130-like receptor chain IL-31RA, and the receptor subunit OSMRβ that is shared with another family member oncostatin M (OSM). Binding of IL-31 to its receptor activates Jak/STAT, PI3K/AKT and MAPK pathways. IL-31 acts on a broad range of immune- and non-immune cells and therefore possesses potential pleiotropic physiological functions, including regulating hematopoiesis and immune response, causing inflammatory bowel disease, airway hypersensitivity and dermatitis. This review summarizes the recent findings on the biological characterization and physiological roles of IL-31 and its receptors.  相似文献   
115.
为检测生殖系统癌有无HLA-G表达,采用免疫组化LDP法对223例生殖系统癌手术切除标本进行了鼠抗HLA-G单克隆抗体染色,观察了HLA-G在乳腺癌(n=100),卵巢癌(n=30),子宫颈癌(n=30),子宫内膜癌(n=40),前列腺癌(n=20)和睾丸胚胎癌(n=3)中的表达与分布。结果发现,除睾丸胚胎癌外,生殖系统其余部位癌标本可见到40-57.5%的HLA-G阳性表达,HLA-G阳性反应物在癌细胞内呈颗粒状及均质状,主要分布于细胞浆,结果提示,HLA-G表达可能是肿瘤生物学中的普遍现象,生殖系统癌细胞在发生和发展过程中其基因表达有可能出现反分化现象,开始表达HLA-G,从而使癌细胞产生免疫耐受,逃逸宿主的免疫监视。  相似文献   
116.
同时表达多种外源基因的非复制型重组痘苗病毒的构建   总被引:13,自引:5,他引:8  
利用非复制型痘苗病毒载体,构建了能同时表达乙型肝炎(乙肝)病毒SS1、麻疹病毒HA和F及白细胞介素2(IL-2)的非复制型重组痘苗病毒VIHIL2△CKSS1,及其相应的复制型重组豇轩病毒VHFIL2SS1。这两株重组病毒在CEF细胞上连续传至第25代,经Southern,两株病毒均在A24、A27间稳定整合有SS1基因,非复制型重组病毒C、K间基因稳定缺失。经RIA、ELISA及Western  相似文献   
117.
118.
利用PCR技术,从A型产气荚膜梭菌标准株染色体DNA中扩增出α毒素基因,构建了含α毒素基因的重组菌株BL21(DE3)(pXETA02)。经酶切鉴定和序列测定证实,构建的表达质粒pXETA02含有α毒素基因序列。经SDS-PAGE、Western blot分析和ELISA检测,重组菌株表达的α毒素蛋白能够被α毒素单抗识别。表达优化结果表明,以IPTG为诱导剂诱导α毒素表达的优化条件是:培养基pH 7.5,培养温度37℃,IPTG浓度0.8mmol/L,菌体生长密度OD600达到0.8时加入IPTG,诱导时间5h,此时α毒素蛋白表达量为34.83%。以乳糖为诱导剂诱导α毒素表达的优化条件是:培养基pH7.5、培养温度37℃,乳糖浓度0.1g/L,菌体生长密度OD600达到0.8时加入乳糖,诱导时间5h,α毒素蛋白表达量为23.82%。动物实验结果表明,用重组菌株α毒素蛋白免疫的小鼠可以抵抗1MLD的A型产气荚膜梭菌标准株C57-1毒素攻击。  相似文献   
119.
外源基因的引入及表达常会引发宿主动物强烈的免疫应答,导致蛋白产量的下降或引起炎症反应。本研究试图通过在胚胎发育早期接种异源抗原诱导动物产生免疫耐受来解决这些问题。为了诱导鸡产生免疫耐受,将人血清白蛋白(Human serum albumin,HSA)通过胚胎血管微注射的方式接种到发育65—67h的鸡胚血管中,接种剂量为50μg;通过卵黄注射的方式接种到发育3—7d的鸡胚卵黄中,接种剂量为100μg。孵出的小鸡在3周龄时按照常规免疫方法再次接种同种抗原,收集不同时期的血清样本,用酶联免疫吸附试验(Enzyme-linked immunosorbent assay,ELISA)检测血清中抗-HSA抗体水平。结果表明,两种接种方式均能诱导小鸡产生免疫耐受:在65-67h的胚胎中通过血管微注射法接种抗原诱导小鸡产生免疫耐受的比率为64.52%;通过卵黄注射接种抗原诱导小鸡产生免疫耐受的最佳接种时间为发育的第6d,第5、7d接种对后期血清中抗-HSA抗体形成也有一定抑制作用,但是维持耐受的时间较短,第3、4d接种抗原对诱导小鸡免疫耐受的效果不明显[动物学报51(5):845—851,2005]。  相似文献   
120.
A colony bank of yeast dna obtained by cloning HindIII-generated fragments of total yeast nuclear DNA in Escherichia coli K-12 with the vector pBR322, was screened with a radioactive RNA probe enriched for a subset of ribosomal protein mRNAs. The selected recombinant DNA molecules were hybridized with poly(A)-containing mRNA under R-loop conditions. From the DNA-RNA hybrids the respective mRNAs were melted off and translated in vitro in a rabbit reticulocyte cell-free system. The translational products were analyzed by immunoprecipitation with antibodies raised against ribosomal proteins. The identity of the ribosomal protein gene products was further established by electrophoresis on two-dimensional gels. At least 15 recombinant DNA molecules were shown to contain ribosomal protein genes. Four of them, i.e. Y65, Y89, Y113 and Y138, have been characterized preliminarily.  相似文献   
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