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101.
目的:研究双源CT 冠状动脉血管成像诊断心肌桥的临床价值。方法:选择260 例具有典型心前区不适的患者进行双源CT 冠脉血管成像检查,观察其发生部位,测量其长度和深度并进行分析。结果:260 例受检患者中,62例共70 段存在心肌桥,检出率 达20.76%,高于文献报道的检出率18.2%。所有心肌桥均发生于左前降支,其中近段17 段(24.4%),中段43 段(61.4%),远段10 段 (14.2%)。心肌桥平均长度为15.8± 6.4mm,深度为1.4± 0.85mm。结论:双源CT 冠状动脉血管成像因其便捷无创,不受心率严格 限制且价格低廉可作为心肌桥筛查的理想检查手段。  相似文献   
102.
Fibroblast growth factor ligands and receptors (FGF and FGFR) play critical roles in tumorigenesis, and several drugs have been developed to target them. We report the biologic correlates of FGF/FGFR abnormalities in diverse malignancies. The medical records of patients with cancers that underwent targeted next generation sequencing (182 or 236 cancer-related genes) were reviewed. The following FGF/FGFR genes were tested: FGF3, 4, 6, 7, 10, 12, 14, 19, 23 and FGFR1, 2, 3, and 4. Of 391 patients, 56 (14.3%) had aberrant FGF (N = 38, all amplifications) and/or FGFR (N = 22 including 5 mutations and one FGFR3-TACC3 fusion). FGF/FGFR aberrations were most frequent in breast cancers (26/81, 32.1%, p = 0.0003). In multivariate analysis, FGF/FGFR abnormalities were independently associated with CCND1/2, RICTOR, ZNF703, RPTOR, AKT2, and CDK8 alterations (all P < 0.02), as well as with an increased median number of alterations (P < 0.0001). FGF3, FGF4, FGF19 and CCND1 were co-amplified in 22 of 391 patients (5.6%, P < 0.0001), most likely because they co-localize on the same chromosomal region (11q13). There was no significant difference in time to metastasis or overall survival when comparing patients harboring FGF/FGFR alterations versus those not. Overall, FGF/FGFR was one of the most frequently aberrant pathways in our population comprising patients with diverse malignancies. These aberrations frequently co-exist with anomalies in a variety of other genes, suggesting that tailored combination therapy may be necessary in these patients.  相似文献   
103.
目的:探讨18F-FDG PET显像和131I-全身扫描(131I-WBS)SPECT显像对分化型甲状腺癌(DTC)术后转移灶的临床诊断价值。方法:对57例外科术后拟行131I治疗的DTC患者行18F-FDG PET全身显像和131I-WBS扫描,观察和记录在糖代谢和碘代谢中DTC转移灶的定位及数量变化,并同时测定甲状腺球蛋白(Tg),促甲状腺激素释放激素(TSH)等实验室检查项目。结果:57例DTC患者18F-FDG PET显像发现真阳性20例、假阳性3例、真阴性31例、假阴性3例,其灵敏度为87.0%,特异性为91.2%。而131I-WBS扫描发现真阳性13例、假阳性2例、真阴性34例、假阴性8例,其灵敏度为61.9%,特异性为94.4%。PET显像和131I-WBS扫描共检出阳性病灶73个,其中淋巴结32个,肺5个,纵隔6个,骨26个,其他部位4个。PET显像发现43个阳性病灶(58.9%),而131I-WBS检出30个(41.1%)。当Tg水平〉10μg/L时,随着Tg在血清含量的增高,两种显像方法的对DTC转移灶的阳性检出率亦随之升高。结论:两种检查对DTC术后转移灶的监测和131I的治疗具有良好的互补性,18F-FDG PET显像在Tg阳性和131I-WBS阴性的患者的转移灶检出上更具有优势,有重要的临床指导意义。  相似文献   
104.
猪CFL2b 基因cDNA克隆初步分析   总被引:5,自引:1,他引:4  
利用基因表达谱芯片分析法筛选出与大白猪高肌肉产量-肌纤维形成有关的CFL2b基因.参考人和小鼠CFL2b基因序列,采用SMART-RACE技术结合EST序列拼接技术,从猪骨骼肌肌肉中首次克隆了猪CFL2b的全长cDNA序列(GenBank登录号EU561660,EU561661),Northern杂交检测CFL2b基因 mRNA.结果表明,猪CFL2b基因含有2个转录本,长转录本3 012 bp,短转录本1 466 bp .CFL2b基因在多种真核生物中都有表达,且编码区序列非常保守,开放式读码框501 bp编码了166个氨基酸的蛋白质.氨基酸序列分析表明,猪CFL2基因与人和小鼠氨基酸同源性分别为100%和99.1%.核苷酸序列相似性分别为88.1%和74.9%.  相似文献   
105.
We report here the new ‘creodont’ Lahimia selloumi gen. et sp. nov. from the late Palaeocene of the Ouled Abdoun Basin (Morocco) as the oldest known Hyaenodontidae with Tinerhodon from the Ouarzazate Basin (Morocco). By contrast to Tinerhodon, Lahimia is unexpectedly derived. Most of its specializations, such as the shortening of the anterior dentition (e.g. loss of P1) and the talonid reduction and simplification, are strikingly shared with Boualitomus from the Ypresian of the Ouled Abdoun Basin, and are distinctive from other hyaenodontids, including ‘proviverrines’. They are interpreted as synapomorphies evidencing a precociously specialized early African hyaenodontid lineage. Although Lahimia and Boualitomus remain known only by the lower dentition, their relationships with Koholia are suggested by comparison of their molar occlusal pattern. Lahimia and Boualitomus are referred to the Koholiinae, which is representative of an old African endemic lineage, as initially recognized. This remarkable lineage is characterized by synapomorphies of Lahimia and Boualitomus, and also by a shared original prevallum/postvallid shearing. The discovery of Lahimia provides direct evidence for the antiquity of the African evolution of the Hyaenodontidae. This is in agreement with an African origin of the Hyaenodontidae, and with the probable diphyletism of the ‘Creodonta’. Lahimia and the Koholiinae, as well as the diversity of the first Laurasian hyaenodontid lineages, emphasize our poor knowledge of the striking early African hyaenodontid radiation.  相似文献   
106.
Variation at five polymorphic microsatellite loci was used to investigate genetic diversity and differentiation of two tetraploid Canarian endemics, Bencomia exstipulata and B. caudata. Data were analysed and are discussed in terms of tetrasomic (autotetraploid) and disomic (allotetraploid) inheritance. In both cases, genetic diversity values were similar to those described in other tetraploid plant species. High genetic differentiation between the only two described natural populations of B. exstipulata was detected (FST = 0.411). Bayesian cluster analysis revealed a geographical structure with distinct genetic groups from each island. High genetic differentiation and low genetic diversity of the B. exstipulata population from Tenerife suggest a recent population bottleneck, perhaps caused by the most recent major volcanic eruption, for this natural locality. This may be heightened by possible inbreeding depression and the monoecy of these species. Polymorphic microsatellite loci were also tested across all species in the Bencomia alliance. These reliably amplified the target sequence, suggesting a high degree of conservation of the sequences flanking the microsatellites. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 429–441.  相似文献   
107.
108.
本研究用Vero细胞或Vero/SLAM细胞从我国10个省(直辖市、自治区,下同)2003~2007年风疹暴发和散发病例的咽拭子标本中分离到57株风疹病毒,用RT-PCR方法扩增了57株风疹病毒E1基因1 107个核苷酸的片段,并对该PCR产物进行序列测定和分析.结果提示,在基于WHO基因定型靶序列739个核苷酸片段构建的基因亲缘关系树上,其中55株风疹病毒株属于1E基因型,相对于其他国家的1E基因型,形成一个独立分支;另外2株风疹病毒属于2B基因型.57株风疹病毒大部分核苷酸的突变为无义突变,氨基酸序列高度保守,除了2株风疹病毒在E1蛋白血凝抑制和中和位点区域第212位氨基酸由Thr变为Ser,其他病毒株均无重要抗原位点的改变;所有我国已分离到的1E基因型风疹病毒在E1蛋白第338位氨基酸共享突变位点(Leu338→Phe338),而其他基因型以及其他国家的1E基因型风疹病毒在该位点均未发生突变,提示该氨基酸(Phe338)可能是我国1E基因型风疹病毒所特有.2003~2007年在我国10个省均分离到1E基因型,而2B基因型只在2006年从四川省的越南输入病例中分离到,提示1E为绝对优势基因型,2B基因型为输入基因型.与1979~1984年和1999~2002年我国流行的风疹基因型不同,发生了基因型的更替,近年我国风疹的流行是由1E基因型为主的风疹野病毒的多个传播链引起.  相似文献   
109.
放牧后羊草和芦苇叶组织转化的比较   总被引:8,自引:3,他引:5  
运用组织转化理论与分析方法,对羊草与芦苇在放牧后的叶组织转化进行了比较研究。结果表明,整个生长季内,除5月份外,芦苇的绿叶数大于羊草,羊草的绿叶长大于芦苇;2种禾草的叶片发生率和伸长率均在生长初期最大,以后逐渐降低,萎蔫率正好相反;芦苇叶片寿命短,叶组织转化快、叶组织物质积累呈抛物线型增长,如果不及时利用,会造成资源的浪费,羊草叶片寿命较长,叶组织转化慢。可以通过不同的利用方式和时间来改善羊草草地的质量。  相似文献   
110.
猪CFL2b基因主要在骨骼肌中表达,对肌肉的发育和肌纤维的形成具有一定作用。为了解猪CFL2b基因与肌纤维性状的相关性,利用定向克隆和基因转染技术获得能稳定表达猪CFL2b基因的成肌细胞株,荧光显微镜观察及Western Blotting检测CFL2b基因在成肌细胞中的表达;应用实时定量PCR技术对细胞内肌球蛋白重链基因(MyHC)的表达变化进行检测。结果显示:CFL2b基因对MyHC的表达有明显影响,其中MyHC2x基因和MyHC26基因的表达明显上调,MyHCl/slow的表达变化不明显。表明CFL2b基因与猪的肌纤维性状密切相关,推测猪CFL2b基因的高表达可能导致猪的不良肉质性状,可以考虑将CFL2b基因作为猪肉质性状的候选基因[动物学报54(6):1014—1019,2008]。  相似文献   
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