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91.
目的了解玉米紫色植株花色苷色素对小鼠肠道菌群的影响。方法按中华人民共和国卫生部《保健食品检验与评价技术规范》中的动物实验调节肠道菌群功能的检验方法,观察玉米紫色植株色素对小鼠肠道中肠杆菌、乳杆菌、双歧杆菌数量的影响。结果灌服后小鼠肠道乳杆菌、双歧杆菌数量变化差异均无显著性,低剂量组肠扦菌数量明显低于灌服前(P〈0.05),其他组肠杆菌数量变化差异无显著性。结论玉米紫色植株色素对小鼠肠道菌群可能有影响。  相似文献   
92.
发现9种新的人类染色体异常核型,分别为: 46, XX, t(2; 10)(q33; q11); 46, XY, t(10; 12)(q26; q22); 46, XY, t(6; 15)(p23; q23); 46, XY, t(1; 6)(p36; q21); 46, XY, t(1; 19)(p32; p13); 46, XY, t(16; 18)(q22; q21); 46, XY, inv(1)(p36q25); 46, XY, t(13; 17)(q12; q25); 46, XY, t(15; 21)(q26; q11)。异常核型是导致自然流产和不育的原因。 Abstract Nine new kinds of human chromosomal abnormal karyotypes were reported. They were46, XX, t(2; 10)(q33; q11); 46, XY, t(10; 12)(q26; q22); 46, XY, t(6; 15)(p23; q23); 46, XY, t(1; 6)(p36; q21); 46, XY , t(1; 19)(p32; p13); 46, XY, t(16; 18)(q22; q21); 46, XY, inv(1)(p36q25); 46, XY, t(13; 17)(q12; q25) and 46, XY, t(15; 21)(q26; q11). The chromosomal anomalies were the causes of spontaneous abortions and infertilities.  相似文献   
93.
INTRODUCTIONOpioidreceptorsaremembersofthefamilyofG-protein-c0upledreceptorswhichnegativelyregulatetheactivityofadenylylcyclase.Theyareconsideredtomedi-atepharmaco1ogicaleffects,inc1udinganalgesia,sedati0n,euphoria,andrespirat0rydepression.Threemajorsubtypes0f0pioidreceptors,designatedasptK5and6,havebeenwellcharacterizedbypharmac0l0gicalstudies[1],andcDNAsforeachhavebeencloned[2].However,opioidreceptorsarenotexpressednaturallyingreatabundance,theyarerelativelylabileandratherdifficultt0s…  相似文献   
94.
95.
INTroDUCTION.7-aminobutyric acid (GABA), a major in-hibitory neurotransmitter in vertebrate brain, in--duces neuronal inhibition via GABA receptors. Adeficiency of GABAergic inhibition has been hy-pothesized to be a principal factor in the patho-genesis of epilepsy[1]. GABA transporters are im-portant components of the GABAergic system, andfunction in part to terminate the GABA transmis-sion through rapid re-uptake of GABA into thepresynaptic neurons and surrounding gliaJ cells[2…  相似文献   
96.
环境因子对野化培训大熊猫在生境斑块中行为表现的影响   总被引:1,自引:0,他引:1  
采用动物行为观察中的聚焦动物法和生境斑块调查的样方法, 调查和分析了2003年7月至2004年9月卧龙自然保护区大熊猫"祥祥"在野化培训圈中的行为表现及其与环境因子的关系.结果 表明:野化培训大熊猫在生境斑块中的行为表现主要以取食为主,占63.14%,其次是移动行为和休息行为,分别为15.85%和8.91%,爬树行为最少,仅0.23%;且不同月份各种行为类型的分配格局具有相似模式,无显著性差异(P=1.0).分析食物分布对大熊猫行为表现的影响,其取食、吃馍和称重、休息以及饮水等行为在有无竹子分布的斑块之间差异显著(P<0.05),而其它行为不甚明显(P>0.05).从生境结构的环境组成因子来看,野化培训大熊猫的行为表现除与斑块个别组成因子具有较为明显的相关关系之外(P<0.05),与其它环境因子均无显著性相关(P>0.05).据此对产生这种结果的原因进行了探讨,并对今后圈养大熊猫的野化培训提出了建议.  相似文献   
97.
采用淀粉凝胶电泳法,对云南彝、白、哈尼、壮、傣、苗、傈僳、回、拉祜、佤、纳西、瑶、藏、景颇、布朗、普米、怒、阿昌、德昂、基诺、布依、独龙和苦聪人等23个少数民族人群的红细胞腺苷酸激酶(AK1)的多态分布进行了调查。结果,在23个人群中均未检出AK21纯合子。但在彝、回、景颇、布朗、怒和德昂6个民族中检出了AK21杂合子,AK21基因频率在这6个民族中的分布在0.0045-0.0446之间,其中,仅回族的AK21基因达多态水平。 Abstract:The investigation on the distribution of adenylate kinase(AK1)polyorphism in 23 ethnic groups in Yunnan province of China,including the minorities of Yi,Bai,Hani,Zhuang,Dai,Miao,Lisu,Hui,Lahu,Wa,Naxi,Yao,Tibetan,Jingro,Bulang,Pumi,Nu,Achang,Deang,Jino,Buyi,Dulong and Kucong people,was carried out,using starch gel electrophoresis.The results showed that no AK21,homozygote and other variations were found.But AK21 heterozygotes were found in the minorities of Yi,Hui,Jingpo,Bulang,Nu and Deang.The ranges of AK21 gene frequencies were 0.0045-0.0446.  相似文献   
98.
Ion beams have been widely usedinthe semiconduc-tor industryand appliedfor surface modificationof materi-als since the1970s,while nobody had discussed howthese ion beams could be used in genetic modification inbiological science,evenfewpeople paid attentionto bio-logical effects induced byion beamandtheir possible usein genetics.In1986,Yu et al.have discovered the ge-netic effects in rice mediated by low energy ions[1—5].Since thenion beamradiation has been widely usedtoim-prove crops and the performance of...  相似文献   
99.
Establishing non-human primate models of human diseases is an efficient way to narrow the large gap between basic studies and translational medicine. Multifold advantages such as simplicity of breeding, low cost of feeding and facility of operating make the tree shrew an ideal non-human primate model proxy. Additional features like vulnerability to stress and spontaneous diabetic characteristics also indicate that the tree shrew could be a potential new animal model of human diseases. However, basal physiological indexes of tree shrew, especially those related to human disease, have not been systematically reported. Accordingly, we established important basal physiological indexes of domesticated tree shrews including several factors: (1) body weight, (2) core body temperature and rhythm, (3) diet metabolism, (4) locomotor rhythm, (5) electroencephalogram, (6) glycometabolism and (7) serum and urinary hormone level and urinary cortisol rhythm. We compared the physiological parameters of domesticated tree shrew with that of rats and macaques. Results showed that (a) the core body temperature of the tree shrew was 39.59±0.05 °C, which was higher than that of rats and macaques; (b) Compared with wild tree shrews, with two activity peaks, domesticated tree shrews had only one activity peak from 17:30 to 19:30; (c) Compared with rats, tree shrews had poor carbohydrate metabolism ability; and (d) Urinary cortisol rhythm indicated there were two peaks at 8:00 and 17:00 in domesticated tree shrews, which matched activity peaks in wild tree shrews. These results provided basal physiological indexes for domesticated tree shrews and laid an important foundation for diabetes and stress-related disease models established on tree shrews.  相似文献   
100.
Human embryonic stem cells(hESCs)have been successfully differentiated into hematopoietic progenitor cells with colony formation capacity and further into various kinds of blood cells including erythrocytes,megakaryocytes,neutrophils,nature killer cells and T lymphocytes[1 7].Nevertheless,the differentiation efficiency is extremely low.  相似文献   
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