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81.
目的:构建携带人SP-B蛋白+1580 SNP不同等位基因的转基因小鼠并进行细菌性肺炎模型的造模。方法:利用受精卵原核注射技术将hSP-B基因整合至小鼠染色体上获得F0代小鼠,将其与mSP-B基因敲除鼠进行交配,逐步去除转基因小鼠体内m SP-B基因。利用PCR技术鉴定小鼠基因型,通过测序确定+1580位点的等位基因。将铜绿假单胞菌经支气管灌注接种至小鼠肺内进行细菌性肺炎造模,对照组注射等量灭菌生理盐水。结果:F2代小鼠只表达人SP-B蛋白而不表达鼠SP-B蛋白,蛋白表达量与人肺内含量相近,即为构建成功的转基因小鼠。3个小鼠家系+1580位点等位基因为T,1个家系为C。细菌接种(1×10~6CFU/mouse)后24小时,小鼠肺泡内炎症渗出明显,大量中性粒细胞浸润,SP-B蛋白含量明显降低,但不同等位基因间在此条件下无明显差异。结果:成功构建只表达人SP-B蛋白的转基因小鼠模型,细菌性肺炎模型造模成功,为今后进一步研究人SP-B蛋白的生理功能及+1580基因多态性与肺疾病的关系提供了有力的工具。 相似文献
82.
Ethanol disrupts the formation of hypochord and dorsal aorta during the development of embryonic zebrafish 总被引:2,自引:0,他引:2
QIAN Linxi WANG Yuexiang JIANG Qiu ZHONG Tao & SONG Houyan Key Laboratory of Molecular Medicine Ministry of Education Shanghai Medical School of Fudan University Shanghai China 《中国科学:生命科学英文版》2005,48(6):608-615
It has been demonstrated that maternal drinking during pregnancy had serious adverse effects on the health of the newborns. Fetal alcohol syndrome (FAS) is the most important developmental abnormality caused by maternal alcohol abuse during pregnancy. Clinically, it is characterized by head and facial ab-normalities, cardiovascular malformation, and perma-nent nervous system damage[1,2]. A lot of experimental models have been developed to study the ethanol’s effects on embryonic development,… 相似文献
83.
Study of the tolerance of Hippochaete ramosissimum to Cu stress 总被引:1,自引:0,他引:1
LIU Dengyi LI Ying CHU Ling WANG Guanglin & WANG Lilong Biodiversity Research Center Anhui Normal University Wuhu China The Provincial Key Laboratory of Conservation Exploitation of Biological Resources in Anhui Wuhu China 《中国科学:生命科学英文版》2005,48(Z1)
We investigated the tolerance of Hippochaete ramosissimum and the changes in physiological metabolism following exposure to copper using pot experiments and analyzing plant physiology and biochemistry. The results showed that Cu tolerance in Hippochaete ramosissimum varied significantly between different populations; the tolerance of plants living in Cu polluted areas for extended periods of time exceeded that of plants living in unpolluted areas. SOD and POD activities in highly Cu tolerant plants increased noticeably following exposure to Cu. This indicates that maintaining and increasing the two kinds of protective enzyme activities are the primary foundations of plant tolerance. However, no change in CAT activity was demonstrated following Cu exposure. In summary, there existed considerable differences in physiological metabolism between different populations of Hippochaete ramosissimum following exposure to Cu. 相似文献
84.
Gene cloning and expression of cadherin in midgut of Helicoverpa armigera and its Cry1A binding region 总被引:1,自引:0,他引:1
WANG Guirong WU Kongming LIANG Gemei & GUO Yuyuan State Key Laboratory of Plant Disease Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Be China 《中国科学:生命科学英文版》2005,48(4):346-356
Bacillus thuringiensis (Bt), a Gram-positive bacte-rium, produces insecticidal crystal proteins during sporulation. Bt has been used as biopesticides to con-trol a number of insect pests from Lepidoptera, Dip-tera and Hymenoptera and also has become so far the leading gene sources of transgenic plants resistant toinsect pests[1,2]. In China, the use of Bt cotton began in 1997 in Hebei, Shandong and Henan provinces, etc. and rapidly increased to more than 2 million ha in 2002, which is effe… 相似文献
85.
CHEN Ruijuan JIANG Jiangang XIAO Xiao & WANG Daowen . The Institute of Hypertension Department of Internal Medicine Tongji Hospital Tongji Medical College Huazhong University of Science & Technology Wuhan China . Departments of Molecular Genetics Biochemistry & Gene Therapy Center University of Pittsburgh Pittsburgh PA USA 《中国科学:生命科学英文版》2005,48(5):495-505
Vascular endothelial cells play crucial roles in regulating cardiovascular function, maintaining car-diovascular homeostasis and preventing the occur-rence of cardiac and cerebral vascular diseases. All these protective effects are fulfilled through various vasoactive products secreted by endothelium including nitric oxide (NO), prostacyclin (PGI2) and endothe-lium-derived hyperpolarizing factor (EDHF). NO, pro-duced from L-arginine by endothelial nitric-oxide synthase (eNOS), is an impor… 相似文献
86.
Construction of a cucumber genetic linkage map with SRAP markers and location of the genes for lateral branch traits 总被引:7,自引:0,他引:7
WANG Gang * PAN Junsong * LI Xiaozun HE Huanle WU Aizhong & CAI Run Agriculture Biology School of Shanghai Jiaotong University Shanghai China 《中国科学:生命科学英文版》2005,48(3):213-220
Cucumber (Cucumis sativus L. 2n = 2x = 14), thatbelongs to Cucurbitaceae family, is one of majorvegetables with a planting area second to that of to-mato in the world[1]. Due to its economical importanceplant breeders and geneticists have paid much atten-tion to the genetic study on this important vegetablecrop, but the research progress in cucumber is muchless than that in tomato. In 1990, Pierce[2] reviewed allthe reported genes of cucumber that had been geneti-cally analyzed since the 1930… 相似文献
87.
绵羊胎儿成纤维细胞体外培养及转基因研究 总被引:2,自引:0,他引:2
目的用增强型绿色荧光蛋白(EGFP)基因转染体外培养绵羊胎儿成纤维细胞,探讨绿色荧光蛋白对绵羊胎儿成纤维细胞生物学特性的影响.方法体外分离培养绵羊胎儿成纤维细胞,经脂质体介导EGFP基因转染第一代成纤维细胞,G418筛选10~12*!d,挑选转基因单克隆细胞,传代培养,进行细胞形态观察、生长曲线以及染色体核型分析,并进行了培养细胞性别鉴定.结果整合有EGFP基因的绵羊胎儿成纤维细胞生物学行为与未转染外源基因的细胞无明显差别,根据荧光强度可直接反应外源基因的表达量.结论 EGFP基因作为体内报告基因可用于转基因细胞的研究,并将整合有EGFP基因的转基因细胞为克隆动物提供核供体奠定了基础. 相似文献
88.
胚胎干细胞的生长是由一个极其复杂的网络系统调控的,本文简要叙述了Oct-4、Nanog、Sox2三个转录因子对胚胎干细胞生长的调控作用,为将来更好的开发利用胚胎干细胞资源奠定理论基础. 相似文献
89.
Considering the great physiological and behavioral similarities with humans, monkeys represent the ideal models not only for
the study of complex cognitive behavior but also for the preclinical research and development of novel therapeutics for treating
human diseases. Various powerful genetic technologies initially developed for making mouse models are being explored for generating
transgenic primate models. We review the latest genetic engineering technologies and discuss the potentials and limitations
for systematic production of transgenic primates.
Supported by Funding from GRA, NIMH and NIA. 相似文献
90.
盐胁迫对扁桃光合特性和叶绿体超微结构的影响 总被引:14,自引:0,他引:14
温室条件下,分别用浓度为150、300、350 mmol/L的NaCl和Na2SO4处理‘石头扁桃’和‘桃扁桃’实生苗植株,处理10 d后分别测定其叶片叶绿素含量、净光合速率、气孔导度、细胞间隙CO2浓度,并观察叶绿体超微结构的变化。研究发现:(1)盐胁迫下,‘石头扁桃’和‘桃扁桃’chl a、chl b均在低浓度盐区含量最高,而在高浓度盐区含量最低,Na2SO4处理区chl a、chl b含量均低于NaCl处理区;(2)‘石头扁桃’和‘桃扁桃’叶片净光合速率随盐浓度的增加而下降,‘石头扁桃’下降的幅度较大;(3)‘桃扁桃’叶片细胞间隙CO2浓度随盐浓度的增加而升高,但‘石头扁桃’叶片细胞间隙的CO2浓度变化没有稳定的规律;(4)2个品种的叶片气孔导度均随盐浓度的增加而降低;(5)盐胁迫后,叶绿体基粒、基质片层扭曲,类囊体肿胀;随盐浓度的增加,形变加剧,叶绿体由椭圆形肿胀成圆形,叶绿体膜解体,且‘石头扁桃’叶绿体对盐胁迫比较敏感。综合分析发现,2种盐胁迫对植物造成伤害的机理不同,‘石头扁桃’的耐盐能力较差。 相似文献