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111.
目的 分析评价2013年新生儿遗传性耳聋基因检测室间质量评价调查结果,以改进和提高耳聋基因检测质量.方法 2013年5月向全国30家开展新生儿耳聋基因检测实验室发放15个批号质控血片,包括线粒体DNA 12SrRNA 1555A>G(批号201311~201315)、SLC26A4 IVS7-2A>G(批号201321 ~201325)、GJB2 235delC(批号201331 ~ 201335).实验室自愿参加此次调查活动,并按照规定格式上报结果、测定方法、仪器和试剂等相关信息.组织者采用Clinet EQA程序、Microsoft Excel 2007和SPSS 13.0软件对各实验室检测结果进行统计分析,对质控样本的结果采用正确率(回报结果正确实验室数/参加该项目检测实验室总数)进行描述性评价.结果 有24家实验室回报了线粒体DNA 12SrRNA基因1555A>G检测结果,回报率为80.0%(24/30),5个批号的正确率分别为95.8%(23/24)、95.8%(23/24) 、100%(24/24)、95.8% (23/24)和95.8%(23/24),总体批号中正确率为96.7%(116/120).有23家实验室分别回报了SLC26A4基因IVS7-2A>G和GJB2基因235delC质控血片的检测结果,回报率为76.7% (23/30);IVS7-2A>G 5个批号的正确率分别为95.7%(22/23)、95.7%(22/23)、100%(23/23)、95.7%(22/23)和95.7%(22/23),总体批号中正确率为96.5%(111/115);235delC 5个批号的正确率均为100%(23/23).本次调查中约2/3的实验室使用了荧光PCR法,约1/3的实验室使用了微阵列芯片法.结论 本次新生儿遗传性耳聋基因检测室间质量调查结果总体上是满意的,线粒体DNA12SrRNA基因和SLC26A4基因检测部分批号存在着错误的结果.基因检测实验室应加强实验室质量控制意识,及时采取措施纠正检测过程中出现的偏差和错误,提高我国新生儿耳聋检测准确度.  相似文献   
112.
目的 观察重组日本血吸虫 2 6kDaGST抗原 (reSjc2 6GST)免疫役用放养水牛 (简称水牛 )后抗体动态及免疫保护性的效果。 方法 试验组 96头水牛 ,用reSjc2 6GST免疫 3次 ,每次间隔 2wk ,3次剂量分别为 0 2、 0 2和 0 1mg。对照组 90头水牛不作免疫 ;观察 2组水牛免疫前及免疫后 2、 5、 9、 12、 15和 2 0个月的抗体水平及血吸虫感染率的变化。 结果 试验组机体产生特异性抗reSjc2 6GST抗体 ,其抗体水平呈明显的梯形升高趋势。试验组免疫后 2 0个月血吸虫感染率比免疫前下降了 62 2 % ,比同期对照组低 67 7%。 结论 用reSjc2 6GST免疫水牛能产生特异性抗体 ,在免疫后 2 0个月内维持较高水平 ,有一定的抗血吸虫自然感染的保护力。  相似文献   
113.
Sbidian E, Feldmann D, Bengoa J, Fraitag S, Abadie V, de Prost Y, Bodemer C, Hadj‐Rabia S. Germline mosaicism in keratitis–ichthyosis–deafness syndrome: pre‐natal diagnosis in a familial lethal form. Keratitis–ichthyosis–deafness (KID) syndrome is an autosomal dominant congenital ectodermal defect characterized by the association of skin lesions, hearing loss and keratitis. Most of the cases appear to be sporadic. KID syndrome is mostly related to mutations of GJB2 gene encoding connexin‐26. Recently, a lethal form of the disease during the first year of life has been reported in two unrelated Caucasian patients. This rare lethal form is caused by the G45E mutation of GJB2 gene. We here report the first pre‐natal molecular genetic diagnosis of the lethal form of KID syndrome relating to a G45E mutation. In the same family, the occurrence of this condition in three other siblings born to African non‐consanguineous healthy parents lead to perform pre‐natal diagnosis for this last pregnancy. Molecular analysis confirms the diagnosis of the lethal form of KID for the fetus. These results establish the role of germline mosaicism in KID syndrome and warrant careful genetic counseling. Furthermore, analysis of our cases and the literature allowed us to define a characteristic severe neonatal phenotype including facial dysmorphy, severe cornification with massive focal hyperkeratosis of the skin with erythroderma, dystrophic nails, complete atrichia and absence of foreskin.  相似文献   
114.
Many tumor cells are resistant to tumor necrosis factor alpha (TNFalpha)-induced apoptosis. Adenovirus early region 1A (AdE1A) sensitizes the otherwise resistant cells to TNFalpha. AdE1A also stabilizes the p53 protein. The present study demonstrates a correlation between AdE1A-induced sensitization and stabilization of p53 in TNFalpha-induced apoptosis since the N-terminal and CR2 regions, the binding sites for CBP/p300, Rb and 26S proteasome regulatory components, are required for both these actions of AdE1A. TNFalpha does not induce apoptosis and AdE1A fails to sensitize TNFalpha cytotoxicity in p53-negative cells. However, introduction of exogenous p53 overcomes the cellular resistance to TNFalpha toxicity and enhances AdE1A sensitization, demonstrating that AdE1A sensitizes TNFalpha-induced apoptosis by its stabilization of p53. A proteasome inhibitor, lactacystin, enhances TNFalpha cytotoxicity in p53-positive and -negative cells, suggesting that accumulation of cellular proteins other than p53 might also regulate the cellular response to TNFalpha signaling.  相似文献   
115.
Interaction of white spot syndrome virus VP26 protein with actin   总被引:14,自引:0,他引:14  
Xie X  Yang F 《Virology》2005,336(1):93-99
VP26 protein, the product of the WSV311 gene of white spot syndrome virus (WSSV), is one of major structural proteins of virus. In this study, when purified virions were treated with Triton X-100 detergent, VP26 protein was present in both the envelope and the nucleocapsid fraction. We have rationalized this finding by suggesting that VP26 protein might be located in the space between the envelope and the nucleocapsid. By using a fluorescent probe method, we have investigated the interaction between VP26 protein and some proteins of host cells. Three major VP26-binding proteins were purified from crayfish hemocytes by affinity-chromatography, in which the protein with an apparent molecular mass of 42 kDa was identified as actin by mass spectrometry (MS). Moreover, the association of VP26 protein with actin microfilaments was confirmed by coimmunoprecipitation.  相似文献   
116.
三磷酸腺苷对人横纹肌肉瘤细胞系诱导分化作用的研究   总被引:1,自引:2,他引:1  
吕桂芝  林仲翔 《解剖学报》1996,27(4):408-411,T015
为了探讨三磷酸腺苷(ATP0对人横纹肌肉瘤细胞增殖和分化的影响,用ATP作用于人横纹肌肉瘤细胞亚系(RDL6)细胞,观察到ATP可抑制RDL6细胞的增殖,使其生长速度明显减慢,作用第5d时增殖抑制率为81%,流式光度术检测;观察到ATP RDL6细胞S期的细胞数明显增多,说明细胞停滞在S期,用罗氏黄荧光染料传法实,AT家恢复RDL6细胞间隙加接通讯功能的作用。用 光细胞化学方法观察到经ATP处理后  相似文献   
117.
Squamous cell carcinoma (SCC) of the oral cavity is a highly invasive tumour of stratified squamous epithelium that spreads through degradation of the basement membrane (BM) and extracellular matrix (ECM). There are currently no reliable tissue or serum markers to predict whether the tumour has metastasized at the time of diagnosis. Verrucous carcinoma (VC) of the oral cavity is a rare low-grade variant of oral SCC that penetrates into the subepithelial connective tissue. Many matrix metalloproteinases (MMPs), such as MMP-1, -2, -7, -9, -13, and -14, as well as integrin receptors have been implicated in cancer invasion. Integrin alphavbeta6 is induced in SCC and appears to be involved in up-regulation of MMP-9 expression by oral keratinocytes and promotion of their migration. The aim of this study was to investigate whether the pattern of MMP expression or that of alphavbeta6 integrin contributes to the differences in the biological behaviour of oral SCC and VC. The results show that the less aggressive nature of oral VC may be connected to its MMP expression profile. Typically, VCs were devoid of epithelial MMP-3, -7, -9, -12 and -13 expression, compared with SCCs. MMP-19 was expressed by epithelial keratinocytes in hyperproliferative areas of verrucous hyperplasia, VC, and SCC, but was absent in the invasive cancer cell nests of SCC. MMP-26 was expressed by hyperproliferative keratinocytes in VC as well as by invasive cancer cells in SCCs. MMP-10 was expressed widely in the epithelium of all SCC specimens. alphavbeta6 integrin expression was also detected in some cases of epithelial hyperplasia but was significantly more abundant in cancers at the invasive front. The absence of MMP-7, -9 and -12 from epithelial cells may serve as a good prognostic marker of non-invasive oral carcinoma. Blocking the activity of invasion-specific MMPs or alphavbeta6 integrin might offer novel therapeutic modalities in early-stage oral carcinoma.  相似文献   
118.
目的 探讨成人与新生儿心脏连接蛋白 4 3(Cx4 3)表达差异。 方法 应用SP免疫组织化学和图像分析方法 ,观测成人与新生儿心脏Cx4 3的蛋白表达。 结果  1 新生儿心脏Cx4 3在心房和心室均呈斑点状遍布于心肌细胞侧面连接处和细胞质内 ,闰盘处极少。 2 成人Cx4 3表达在心房肌非均质分布于细胞侧面连接处和端闰盘处 ;心室肌典型地排列在闰盘处。 3 图像分析表明 ,心肌细胞Cx4 3分布密度 ,新生儿心房 <心室 ,成人心房 >心室。成人心房、心室均低于新生儿。 结论 新生儿Cx4 3主要分布于心肌细胞侧连接处 ,成人心房和心室存在差异。Cx4 3分布密度新生儿心房 <心室 ,成人心房 >心室 ;成人心脏低于新生儿。提示 ,Cx4 3有增龄变化。  相似文献   
119.
A large proportion of non-syndromic autosomal recessive deafness (NSARD) in many populations is caused by variants of the GJB2 gene. Here, the frequency of GJB2 variants was studied in 406 and 183 apparently unrelated children from Kenya and Sudan, respectively, with mostly severe to profound non-syndromic deafness. Nine (2.2 %) Kenyan and 12 (6.6 %) of the Sudanese children only were carriers of variants within the coding sequence of the GJB2 gene. Variants in the 5'-adjacent region were detected in further 115 individuals. A total of 10 novel variants was recognized, among them four variants in the adjacent 5'-region of the GJB2 coding exon 2 (g.3318-6T>A, g.3318-15C>T, g.3318-34C>T, g.3318-35T>G), a 6 base-pair deletion (g.3455_3460del [p.Asp46_Gln48delinsGlu]), a variant leading to a stop codon (g.3512C>A [p.Tyr65X]), synonymous variants (g.3395C>T [p.Thr26], g.3503C>T [p.Asn62], g.3627A>C [p.Arg104]), and one non-synonymous variant (g.3816C>A [p.Val167Met]). In addition, the previously described variants g.3352delG (commonly designated 30delG or 35 delG), g.3426G>A [p.Val37Ile], g.3697G>A [p.Arg127His], g.3774G>A [p.Val153Ile], and g.3795G>A [p.Gly160Ser] were identified. With the exception of g.3318-34C>T and g.3352delG, all variants occurred heterozygously. For most of the variants identified in the Kenyan and Sudanese study population, a causative association with NSARD appears to be unlikely. Compared to many other ethnic groups, deafness-associated variants of the coding region of GJB2 are rare in Sudan and Kenya, suggesting a role of other genetic, or epigenetic factors as a cause for deafness in these countries.  相似文献   
120.
Genetic testing was completed on 1,294 persons with deafness referred to the Molecular Otolaryngology Research Laboratories to establish a diagnosis of DFNB1. Exon 2 of GJB2 was screened for coding sequence allele variants by denaturing high-performance liquid chromatography (DHPLC) complemented by bidirectional sequencing. If two deafness-causing mutations of GJB2 (encoding Connexin 26) were identified, further screening was not performed. If only a single deafness-causing mutation was identified, we screened for the g.1777179_2085947del (hereafter called del(GJB6-D13S1830); GenBank NT_024524.13) and mutations in the noncoding region of GJB2. Phenotype-genotype correlations were evaluated by categorizing mutations as either protein truncating or nontruncating. A total of 205 persons carried two GJB2 exon 2 mutations and were diagnosed as having DFNB1; 100 persons carried only a single deafness-causing allele variant of exon 2. A total of 37 of these persons were c.35delG carriers, and 51 carried other allele variants of GJB2. Persons diagnosed with DFNB1 segregating two truncating/nonsense mutations had a more severe phenotype than persons carrying two missense mutations, with mean hearing impairments being 88 and 37%, respectively (P < 0.05). The number of deaf c.35delG carriers was greater than expected when compared to the c.35delG carrier frequency in normal-hearing controls (P < 0.05), suggesting the existence of at least one other mutation outside the GJB2 coding region that does not complement GJB2 deafness-causing allele variants.  相似文献   
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