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121.
Hermansky–Pudlak syndrome (HPS) is a rare recessive disorder characterized by oculocutaneous albinism or ocular albinism, bleeding diathesis, and other symptoms such as colitis and pulmonary fibrosis. Eleven causative genes have been identified for HPS‐1–HPS‐11 subtypes in humans. We have identified 16 newly reported patients including the first HPS‐2 case in the Chinese population. In a total of 40 HPS patients, hypopigmentation was milder in HPS‐3, HPS‐5, and HPS‐6 patients than in HPS‐1 and HPS‐4 patients. HPS‐1 accounted for 47.5% (19 of 40) of HPS cases which is the most common subtype. Exons 11 and 19 were the hotspots of the HPS1 gene mutations. In total, 55 allelic variants were identified in HPS1–HPS6 gene, of which 17 variants were previously unreported. These results will be useful for the evaluation of the relationship between HPS genotypes and phenotypes, and for the precise intervention of HPS patients in the Chinese population.  相似文献   
122.
The B-cell lymphoma-2 (Bcl-2) family contains six antiapoptotic members, each with a hydrophobic pocket in which Bcl-2 homology region 3 (BH3) helices bind. This binding quenches apoptotic signals from activated BH3 family members. Many tumor cells either have increased expression of one of these six proteins or become overexpressed under treatment. Six fusion proteins made up of glutathione-S-transferase and each of the Bcl-2 members are bound individually to six glutathione bead sets, each set being easily distinguished by its different intensity of red fluorescence. The coated bead sets are washed, combined and incubated with green fluorescent Bim-BH3 peptide and a small molecule in 10-μl wells for 1 h. The green fluorescence signal for each bead set is resolved, and selective inhibitors are expected to reduce the signal for individual bead sets. Each 384-well plate is analyzed in 12 min, measuring 200 of 2,000 beads (~10%) of each type per well.  相似文献   
123.
Mitogen-activated protein kinases (MPKs) play important roles in biotic and abiotic stress responses. In the present study, we identified a tomato MPK gene, SlMPK4, a possible homolog of Arabidopsis AtMPK4, and performed functional analysis to examine its possible roles in biotic and abiotic responses. Expression of SlMPK4 was induced by infection with Botrytis cinerea and by exogenous application of jasmonic acid and ethylene precursor 1-amino cyclopropane-1-carboxylic acid. Knockdown of the endogenous SlMPK4 expression through virus-induced gene silencing in tomato plants (TRV-SlMPK4) resulted in increased susceptibility to B. cinerea. Expression of defense-related genes SlPR1a and SlPR1b were up-regulated in the SlMPK4-silenced plants. Furthermore, silencing of the SlMPK4 gene also resulted in reduced tolerance against drought stress, leading to earlier wilting symptom under drought stress condition, as compared with the control plants. These results suggest important roles for SlMPK4 in disease resistance against B. cinerea and tolerance to drought stress.  相似文献   
124.
125.
In this study, a five-generation Chinese family (family F013) with progressive autosomal dominant hearing loss was mapped to a critical region spanning 28.54 Mb on chromosome 9q31.3-q34.3 by linkage analysis, which was a novel DFNA locus, assigned as DFNA56. In this interval, there were 398 annotated genes. Then, whole exome sequencing was applied in three patients and one normal individual from this family. Six single nucleotide variants and two indels were found co-segregated with the phenotypes. Then using mass spectrum (Sequenom, Inc.) to rank the eight sites, we found only the TNC gene be co-segregated with hearing loss in 53 subjects of F013. And this missense mutation (c.5317G>A, p.V1773M ) of TNC located exactly in the critical linked interval. Further screening to the coding region of this gene in 587 subjects with nonsyndromic hearing loss (NSHL) found a second missense mutation, c.5368A>T (p. T1796S), co-segregating with phenotype in the other family. These two mutations located in the conserved region of TNC and were absent in the 387 normal hearing individuals of matched geographical ancestry. Functional effects of the two mutations were predicted using SIFT and both mutations were deleterious. All these results supported that TNC may be the causal gene for the hearing loss inherited in these families. TNC encodes tenascin-C, a member of the extracellular matrix (ECM), is present in the basilar membrane (BM), and the osseous spiral lamina of the cochlea. It plays an important role in cochlear development. The up-regulated expression of TNC gene in tissue repair and neural regeneration was seen in human and zebrafish, and in sensory receptor recovery in the vestibular organ after ototoxic injury in birds. Then the absence of normal tenascin-C was supposed to cause irreversible injuries in cochlea and caused hearing loss.  相似文献   
126.
西瓜枯萎病是一种世界范围的西瓜毁灭性病害,其病原菌为尖孢镰刀菌西瓜专化型(Fusarium oxysporum f.sp.niveum,FON)。研究病原菌生长发育和侵染的机制是解决病害的根本途径。利用荧光蛋白对细胞或细胞器进行标记,是病原菌研究中的重要方法。该研究利用绿色荧光蛋白和红色荧光蛋白对FON的细胞核和过氧化物酶体进行了荧光标记。通过农杆菌介导转化(Agrobacterium tumefaciens-mediated transformation,AtMT),该文将3种不同的荧光定位载体分别导入FON,获得了细胞核红色荧光标记的转化子(潮霉素抗性,含mCherry-H2B融合蛋白),以及过氧化物酶体绿色(潮霉素抗性,含GFP-PTS1融合蛋白)和红色(潮霉素抗性,含DsRED-PTS1融合蛋白)荧光标记的转化子各1种。在标记细胞核的菌株中,菌丝、孢子都可见明亮、圆形的红色荧光点,荧光点与DAPI染色标记的细胞核区域完全重合。在过氧化物酶体标记的菌株中,菌丝、孢子中可见明亮的红色或绿色荧光成小点状分布,符合过氧化物酶体的分布特征,而且在脂类物质诱导的条件下,荧光点的数量明显增加。此外,该文还利用细胞壁荧光染色剂卡氏白对3种荧光蛋白标记菌株进行染色。结果显示,卡氏白染色产生的蓝色荧光与红、绿荧光蛋白的荧光在FON中互不干扰。转化子继代培养和初步分析表明,其表型与野生型无差异,菌株继代后荧光表达稳定、定位明显。该结果为进一步研究FON细胞器动态、生长发育与致病分子机制提供了方法和工具。  相似文献   
127.
A novel nanoparticle-based electrochemiluminescence (ECL) immunosensor was designed for highly sensitive and selective detection of human cardiac troponin I (cTnI), an important Acute Myocardial Infarction (AMI)-related biomarker, by using N-(aminobutyl)-N-(ethylisoluminol)-functionalized gold nanoparticles (ABEI-AuNPs) as labels. ABEI-AuNPs were successfully synthesized via a simple seed growth method. A great number of luminescence molecules ABEI as stabilizers were coated on the surface of the AuNPs, which exhibited better ECL activities than previously reported luminol functionalized gold nanoparticles. ABEI-AuNPs were used as new ECL labels to build bio-probes by conjugation with secondary antibodies, which showed good ECL activity, immunological activity, and stability. Another kind of AuNPs functionalized with streptavidin was modified on the electrode surface for biotinylated antibodies capture through the specific interaction of biotin/streptavidin and enhancing the electrical connectivity. By combining with the novel ECL labels and amplification of AuNPs and biotin-streptavidin system, a high sensitive sandwich-type electrochemiluminescence immunoassay was developed for detecting human cTnI with a low detection limit of 2 pg/mL. The immunosensor showed good precision, acceptable stability and reproducibility and could be used for the detection of cTnI in real samples, which was of great potential application in clinical analysis. Importantly, the sensitive detection would have far more diagnostic value than would absolute measurements during the early stage of AMI.  相似文献   
128.
跨流域调水工程沿线调蓄湖泊生态状况直接决定工程能否顺利实施。基于2018年4和9月高邮湖底栖动物调查数据,对底栖动物区系组成、群落结构及主要影响因子进行了研究。调查期间共鉴定出底栖动物42种,隶属3门7纲22科;软铗小摇蚊(Microchironomus tener)、霍甫水丝蚓(Limnodrilus hoffmeisteri)、齿吻沙蚕(Nephtys sp.)、苏氏尾鳃蚓(Branchiura sowerbyi)、厚唇嫩丝蚓(Teneridrilus mastix)为调查期间优势物种,相对丰度分别为24.0%、17.7%、8.1%、7.2%和6.5%;两次调查期间底栖动物优势物种组成存在较大差异。密度、物种丰度、香浓指数在4月份显著高于9月份;非度量多维标度排序(NMDS)和多响应置换过程(MRPP)从群落层面证实了两次调查期间底栖动物群落结构的差异性。指示物种分析表明,软铗小摇蚊、霍甫水丝蚓和有栉管水蚓(Aulodrilus pectinatus)是造成两次调查底栖动物群落差异的关键物种。基于距离的冗余分析(dbRDA)表明,高邮湖底栖动物群落在4月份主要受硅酸盐和总磷影响;9月份主要受水深和叶绿素a影响。  相似文献   
129.
雌雄异株植物资源分配模式上往往表现出显著的性别二态性,但在叶片光合及功能性状上是否有差异目前仍未有定论,且与发育阶段的关系尚不明确。阐明上述问题,能够进一步了解雌雄异株植物的生理生态特征,并为理解性别对性二态植物生长发育的影响机制提供理论依据。以雌雄异株绒毛白蜡(Fraxinus velutina Torr.)为研究对象,针对不同发育阶段不同性别植株进行光合特征及叶功能性状测定,采用双因素方差分析了不同发育阶段下雌雄植株光合能力及叶功能性状的性别间差异,采用Pearson检验了雌雄植株各叶功能性状之间的相关性,并采用标准化主轴分析(Standardized major axis regression, SMA)分析不同性别植株净光合速率与叶功能性状的相关性。结果表明性别和发育阶段显著影响植物个体的光合能力和叶功能性状。总体而言,雄树在坐果期和果实成熟期均表现出更强的净光合速率(Pn)、更高的比叶面积(SLA)、叶绿素含量(Chl)和叶氮含量(LNC);而雌树在果实膨大期表现出更强Pn、SLA和Chl。雌雄性别内Pn与SLA、Chl和LNC间均呈显著正相关(P<0.05),雄树的S...  相似文献   
130.
Heregulin can regulate the survival of cardiomyocytes, epithelial cells, neuron, glial cells, and other cell types through binding with the ErbB receptors. The aim of this study is to investigate the effects of heregulin (HRG) on the apoptosis of Bone marrow Mesenchymal stem cells (MSCs). We used the MSCs from adult Sprague–Dawley rats and the model of serum deprivation (SD) and hypoxia-induced apoptosis. The apoptosis was detected by TUNEL method. The apoptosis of MSCs significantly increased 12 h or 18 h after SD and hypoxia, but treatment with HRG significantly decreased the apoptosis induced by SD and hypoxia. Tyrphostin AG1478 (ErbB3/4 inhibitor) or Tyrphostin AG825 (ErbB2 inhibitor) could block this effects of HRG. Akt and ERK were activated by HRG under SD and hypoxia conditions, but HRG had no effects on the activation of JNK and p38. HRG also increased the ratio of Bcl-2/Bax and decreased the activation of caspase3 induced by SD and hypoxia. These results suggested HRG could decrease the apoptosis of MSCs induced by SD and hypoxia through the activation of Akt and ERK, the increase of Bcl-2/Bax ratio and the inhibition of caspase3 activation.  相似文献   
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