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71.
MacELISA、RPHI和IFAT用于流行性出血热早期诊断的比较   总被引:2,自引:0,他引:2  
比较了IgM捕获ELISA(MacELISA)、反向间接血凝抑制试验(RPHI)和间接免疫荧光抗体试验(IFAT)检测流行性出血热(EHF)病人血清特异性抗体的结果。MacELISA对急性期血清IgM抗体的阳性检出率与RPHI对总抗体的阳性检出率相近,两法都具有较高的敏感性。而IFAT检测IgG抗体的阳性率则较低。总抗体滴度(RPHI)与IgG抗体滴度(IFAT)相关(r=0.542,P<0.01),而与IgM抗体滴度(MacELISA)无明显相关(r<0.1)。但进一步研究发现,3日内血清IgM抗体滴度与总抗体滴度(RPHI)存在相关关系(r=0.701,P<0.01),表明IgM抗体可能也与发病初期RPHI的较高的阳性检出率有关。本工作表明,MacELISA作为一种早期诊断方法具有高度的特异性和敏感性,而RPHI操作简便、快速、敏感性高,但存在一定的非特异性。研究还发现,流行区临床诊断为EHF的病人,IFAT(IgG)和RPHI检测均阳性,而MacELISA(IgM)阴性,提示用RPHI进行血清学诊断时,检查双份血清是必要的。  相似文献   
72.
猴脑线粒体DNA提取及限制性内切酶分析   总被引:2,自引:0,他引:2  
本文用冷碱法从2只恒河猴和1只食蟹猴的脑组织中提取mtDNA,最后的得率大约为0.7μgmtDNA/g脑组织,是肝脏组织得率的1/3左右。与肝脏组织相比较,从脑组织中提取mtDNA有以下优点:1.匀浆方便。2.样品中蛋白杂质少,容易彻底抽提去除蛋白质。3.大分子RNA杂质极少,不经Sepharose-4B柱或RNawe处理,就可得到较纯的样品。加之哺乳动物脑的体积较大,哺乳动物脑组织不失为提取mtDNA的一个有用的组织来源。经16种限制性内切酶分析,并与来自同一个体肝脏组织的mtDNA比较,结果进一步证实,mtDNA无组织特异性。对12岁以上老年猴脑mtDNA的分析表明,在衰老中,动物mtDNA的序列可能没有变化,甲基化程度也无显著增高。  相似文献   
73.
本文分析了钮额果蝇的生活力和B染色体的关系。结果表明,银额果蝇的B染色体在其生长和发育过程中具双重性调节作用。一方面,B染色体以单一的形式存在于单雌系核型中,即1B或2Bs,可刺激生长、发育,增强生活力。另一方面,在单雌系的细胞中存在多条B染色体,并形成核型多态性,这似乎对生长和发育又有一定的抑制作用而减弱其生活力。  相似文献   
74.
白腹锦鸡,红腹锦鸡,中国雉鸡SC组型的比较研究   总被引:1,自引:0,他引:1  
以微铺展—硝酸银染色技术制备三种鸡的SC标本,进行电镜观察。结果表明:三种鸡的SC组非常相似,即2n=82,ZZ/ZW型性别决定,雄性为ZZ。除1号SC和Z-SC为中着丝粒外,其余均为端着丝粒。Z-SC的相对长度有明显的细胞间差异;平均相对长度度介于第3和第4号SC之间。三者SC组型上的差异主要表现在相应SC长度上的不同。并对其亲缘关系及在鸟类进化中的可能地位进行了讨论。此外,在微铺展法制备的锦鸡精母细胞SC标本中还发现了巨大中心粒,这在高等动物尚属首次。  相似文献   
75.
The human neurofilament (H) promoter contains multiple binding sites for nuclear proteins including a Proximal (Prox) site centered around the sequence GGTTGGACC and an adjacent pyrimidine (Pyr) tract site centered around the sequence CCCTCCTCCCC. Surprisingly binding to a probe containing the Prox/Pyr region of the NF(H) promoter was competed in gel shifts by an oligonucleotide containing only an Sp1 binding site (GGGGCGGGG). Supershift assays with a polyclonal anti-Sp1 antisera confirmed that Sp1 was part of the complex formed with the Prox/Pyr probe. However neither bacterially expressed Sp1 516C or vaccinia virus expressed full-length Sp1 778C bound to the Prox or Pyr sequences in DNase I footprints or gel shift assays. Gel shift competitions and supershift assays with probes containing either Prox or Pyr tract sites alone demonstrated targeting of Sp1 to the Prox binding site and identified a non-Sp1 containing complex which contains a Prox binding protein. Adding exogenous Sp1 to a HeLa nuclear extract enhanced the Sp1-containing complex but had no effect on the Prox complex. These studies show that Sp1 can be targeted to a non-Sp1 site in the human NF(H) promoter through protein/protein interactions with a distinct sequence specific DNA-binding protein.  相似文献   
76.
头端延髓腹外侧区注射5—羟色胺对应激性高血粘度...   总被引:3,自引:0,他引:3  
翁可  郭学勤 《生理学报》1992,44(3):244-253
Experiments were carried out on 62 wistar rats. The hyperviscosity and elevation of blood pressure were induced by hanging and restraining the rats with their four limbs tied on a frame. It was found that microinjection of 5-HT (25 micrograms/10 microliters) into the 4th ventricle of the brain or bilateral microinjection of 5-HT (4 micrograms/0.5 microliters/site) into rostral ventrolateral medulla (rVLM) reduced stress-induced hyperviscosity (p < 0.01) and elevation of blood pressure (p < 0.01). The effect of 5-HT injected into the 4th ventricle or rVLM was blocked by bilateral microinjection of cinanserine (4 micrograms/0.5 microliter/site) into rVLM. These results suggest that microinjection of 5-HT into 4th ventricle and rVLM could reduce stress-induced hyperviscosity and elevation of blood pressure and these effects were probably mediated via 5-HT receptors in the rVLM.  相似文献   
77.
NMDA受体在海马CA3区习得性TP保持中的作用   总被引:2,自引:1,他引:1  
梁伟国  许世彤 《生理学报》1992,44(4):333-339
The effect of microinjection of 2-amino-5-phosphonovaleric acid (APV), a selective NMDA receptor antagonist, into the rat hippocampal CA3 area on the synaptic efficacy and related conditioned behavior during the acquisition and consolidation of discrimination learning behavior was examined. The results showed: (1) After population spike (PS) amplitude had just increased to the maximum through training i.e. learning-dependent LTP had just formed, APV 1 microliter (2 mmol/L) was injected into CA3 area, then the rats were trained during the time of efficacy of the drug in every experimental block. The result demonstrated that the PS amplitude could not be maintained at the highest level but decreased to the pre-experiment level after 8 blocks. Correct response percentage of rats could not be consolidated with further training but decreased to less than 10%. (2) After the PS amplitude had kept up at the highest level, APV 1 microliter (2 mmol/L) was injected into CA3 area, then the rats were trained during the time of efficacy of the drug in every experimental block, in which case the PS amplitude also could not be maintained at the highest level but decreased to the pre-experiment level after 14 blocks. Correlatively, when the correct response percentage of rats decreased gradually to less than 10%, the conditioned response of the animals extinguished, but its extinction speed was slower than it was in result (1). These results suggest that the NMDA receptor in CA3 area plays an important role in the maintenance of the learning-dependent long-term potentiation.  相似文献   
78.
X P Liang  L A Babiuk    T J Zamb 《Journal of virology》1991,65(10):5553-5557
The gIII glycoproteins of bovine herpesvirus 1 (BHV-1) and of pseudorabies virus (PRV) are structurally homologous. Both proteins also play preeminent roles in mediating virus attachment to permissive cells. To directly compare the functional relation between these glycoproteins, we constructed a recombinant BHV-1 in which the BHV-1 gIII coding sequence was replaced by the PRV gene homolog. The resultant recombinant virus efficiently expressed PRV gIII and then incorporated it into its envelope. The levels of PRV gIII expression and incorporation were equivalent to those achieved by the wild-type virus for BHV-1 gIII. The recombinant virus was fully susceptible to neutralization by anti-PRV gIII neutralizing antibody. In addition, the virus attachment and penetration functions, as well as the virus replication efficiency, which were lost by deleting the BHV-1 gIII gene, were restored by expressing the PRV gIII homolog in its place. These results demonstrated that PRV gIII and BHV-1 gIII share complementary functions.  相似文献   
79.
Observations were made following 130 spontaneous aggressive incidents in two small breeding groups of captive golden monkeys (Rhinopithecus roxellanae roxellanae). Participants were observed both during the first 10 min following these incidents and during matched control observations. An increased contact rate was observed between opponents following the aggressive incident. Post-conflict contacts were characterized by a number of behavior patterns: open mouth, rapid grooming, embrace, and crouching. Adult males played an important role as mediator in agonistic disputes among females: males intervened in 93.6% of female fights. It is speculated that this intervention behavior is related to the species' organization into one-male units.  相似文献   
80.
Summary Pseudomonas acidovorans DMR-11, capable of oxidizing dimethyl sulfide (DMS), was isolated from peat biofilter. DMS as a sole carbon or energy source was not degraded, but it was co-degraded in the medium containing organic carbon sources. The removal rate of DMS in heat-treated glucose medium was 1.12×10–17 mole/h cell at 30 °C. Dimethyl sulfoxide (DMSO) was the only product of DMS oxidation and was formed stoichiometrically. DMS was reversibly evolved in excess of DMSO. The cell free extract of strain DMR-11 oxidized DMS in presence of NADPH.  相似文献   
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