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1.
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.  相似文献   
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目的:探讨280例胃食管反流病(GERD)的分布特点及危险因素。方法:对临床诊断和胃镜确诊的280例GERD患者进行临床和风险因子相关性分析。结果:不论汉族还是维族,男性患者比例均明显高于女性;汉族患者高发年龄段早于维族患者(z=-2.939,P=0.003,);汉族和维族患者占反流性食管炎和Barrett食管比例分别为42.4%、81_3%及56.5%、18.8%,其中汉族患者Barrett食管比例较高(X2=14.358,P=0.000);肥胖、习惯性便秘、重体力活动者、饮食习惯不良在维族患者中的比例较高(P〈0.001)。结论:GERD与性别、年龄密切相关,男性多于女性,汉族患者发病年龄高峰旱于维族患者;汉族患者Barrett食管发生比例高于维族患者;肥胖、习惯性便秘、重体力活动、饮食习惯不良可能是GERD尤其是维族人群GERD的危险因素。  相似文献   
4.
Effect of different concentrations of salts on natural and recombinant strains of Bacillus subtilis and Escherichia coli was studied. The recombinant strain of B. subtilis was found to be more osmotolerant than the wild-type strain of this bacterium, whereas the opposite situation was observed for the recombinant and wild-type strains of E. coli. Some salts exerted a bacteriostatic effect on E. coli and B. subtilis. The adaptive capacity of recombinant strains depended on the number of plasmid copies in the cells. The introduction of recombinant bacteria into model ecosystems resulted in the generation of their variants with increased osmotolerance.  相似文献   
5.
A general approach to assessing the anthropogenic impact on lake ecosystems is proposed and exemplified for the case of Lake Shira (Republic of Khakasia, Russia). The impact strength is estimated by applying neural network-based methods to samples of data on interdependent marking features of autochthonous and allochthonous bacteria isolated from the lake in 1997–2001. The proposed combination of analysis methods makes it possible to determine the state of an ecosystem from both small-and large-size samples of data having complex interrelations.  相似文献   
6.
湖南省双季稻生产系统碳效率   总被引:2,自引:0,他引:2  
提高农作物生产系统的碳效率是实现低碳农业的重要途径之一.本文采用2004—2012年农作物产量、农田作物生产系统农资投入等统计数据,利用生命周期法和投入产出法,对湖南省双季稻生产系统碳排放、碳吸收和碳效率特征及其动态进行估算.结果表明:湖南省2004—2012年双季稻生产系统年均碳排放总量为656.4×107kg CE,其中化肥和农药生产运输碳排放占农资投入碳排放总量的大部分,分别约占70.0%和15.9%,碳排放总量年际间持续降低,年均降低率为2.4%,碳排放强度则表现为增长趋势;湖南双季稻生产系统2004—2012年年均碳吸收总量为1547.0×107kg C,也呈现逐年降低的趋势,年降低率为1.2%,单位面积稻田碳吸收强度则表现为增长趋势;碳生产效率呈现缓慢增加的趋势,碳经济效率随着年份递进增加幅度较大,年均增长率为9.9%,碳生态效率则表现为稳定且较低,保持在2.4kg C·kg-1CE左右.表明湖南近几年双季稻生产系统碳综合效率提高缓慢,降低肥料和农药的投入量,提高利用效率是提高双季稻生产系统碳效率的关键.  相似文献   
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目的:探讨烟龄≥15年,日吸烟量≥15支的无症状男性吸烟者的肺功能改变情况。方法:选择男性无症状吸烟者190人及非吸烟者180人,进行肺功能测定,并比较两组人群的肺功能改变情况。结果:吸烟组与非吸烟组比较,肺活量(VC)、用力肺活量(FVC)、第1秒用力呼气容积(FEV1)、Tiffeneau 1秒率(FEV1/VC)结果改变不明显,而Gaensler 1秒率(FEV1/FVC)、最大分钟通气量(MVV)、用力呼气50%肺活量的呼气流量(FEF50%)、用力呼气75%肺活量的呼气流量(FEF75%)、呼出25%~75%肺活量时的平均流量(FEF25%~75%)、肺一氧化碳弥散量(DLCO)结果均有显著降低,有统计学意义。结论:通过对无症状吸烟人群肺功能测定结果进行分析。发现有些吸烟者虽无临床症状,但已经出现了小气道及肺弥散功能的损伤,提醒吸烟者应早期戒烟,关爱自身健康,净化生存环境,提高生活质量。  相似文献   
8.
棉酚(G)及其相关物甲氧基半棉酚(DHG)、半棉酚酮(HGQ)、半棉酚(HG)、杀实夜蛾素(H1-4)等是棉花中重要的抗虫性萜烯类次生物质.利用高效液相色谱法(HPLC)对棉酚及其相关物进行了分离,测定了棉叶中的棉酚含量,讨论了不同的提取方法和测定条件对结果的影响,给出了一套简便、快速的分析测试方法,同时与紫外-可见分光光度法(苯胺法)的结果进行了对比,认为对于棉花的抗虫性的研究来说,HPLC是比较适宜的方法.  相似文献   
9.
In the second half of 2005, a large-scale outbreak of influenza in poultry and wild birds was caused by a highly pathogenic H5N1 influenza virus in Russia. The level of pathogenicity is a polygenic trait, and most individual genes contribute to the influenza A virus pathogenicity in birds, animals, and humans. The full-length nucleotide sequences were determined for H5N1 strains isolated in the Kurgan region (Western Siberia). The structure of viral proteins was analyzed using the deduced amino acid sequences. The receptor-binding site of hemagglutinin (HA) in strains A/chicken/Kurgan/05/2005 and A/duck/Kurgan/08/2005 was typical for avian influenza viruses and contained Glu and Gly at positions 226 and 228, respectively. The structure of the basic amino acid cluster located within the HA cleavage site was identical in all isolates: QGERRRKKR. According to the neuraminidase structure, all H5N1 isolates from the Kurgan region were assigned to the Z genotype. Amino acid residues typical for the avian influenza virus were revealed in 30 out of 32 positions of M1, M2, NP, PA, and PB2, determining the host range specificity. One of the strains contained Lys at position 627 of PB2. Isolates from the Kurgan region were shown to have a remantadine-sensitive genotype. Both strains contained Glu at position 92 of NS1, indicating that the virus is interferon-resistant. Phylogenetic analysis related the Kurgan isolates to subclade 2 of clade 2 of highly pathogenic H5N1 influenza viruses.  相似文献   
10.
Lobova  T. I.  Listova  L. V.  Popova  L. Yu. 《Microbiology》2004,73(1):89-93
A study of the horizontal and vertical distribution of heterotrophic bacteria in brackish Lake Shira in summer periods showed that mesophilic bacteria dominated in all areas of the lake, whereas psychrotolerant bacteria dominated in the metalimnion and hypolimnion of its central part. Nonhalophilic bacteria were mostly mesophilic and dominated in coastal waters. Most psychrotolerant bacteria were able to grow in the presence of 5–10% NaCl. Heterotrophic bacteria isolated in different regions of the lake were identified to a generic level. The isolates were classified into autochthonous and allochthonous microorganisms on the bases of their distribution pattern in the lake water, halotolerance, and ability to grow at low temperatures.  相似文献   
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