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101.
102.
FLORÉAL SOLÉ EMMANUEL GHEERBRANT MBAREK AMAGHZAZ BAÂDI BOUYA 《Zoological Journal of the Linnean Society》2009,156(4):827-846
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
103.
MIGUEL ANGEL GONZÁLEZ‐PÉREZ M. DOLORES LLEDÓ CHRISTIAN LEXER MICHAEL FAY MANUEL MARRERO ANGEL BAÑARES‐BAUDET EDUARDO CARQUÉ PEDRO A. SOSA 《Botanical journal of the Linnean Society. Linnean Society of London》2009,160(4):429-441
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
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汉滩病毒M、S基因不同拼接方式在昆虫细胞中融合表达效果比较 总被引:1,自引:0,他引:1
将汉滩病毒囊膜糖蛋白G1与核蛋白(NP)部分片段以不同方式拼 接,构建G1S0.7或S0.7G1嵌合基因,分别插入杆状病毒表达载体pFBD,转化DH10Bac致敏菌, 获得含有嵌合基因的重组穿梭质粒Bacmid,用其转染Sf9细胞,快速筛选出含有G1S0.7或S0.7 G1嵌合 基因的重组杆状病毒,在昆虫细胞中表达外源融合蛋白.利用间接免疫荧光、ELISA和免疫 印迹对表达产物进行检测.结果表明,含G1S0.7嵌合基因之重组杆状病毒可在昆虫细胞中表 达出融合蛋白,该蛋白可被抗汉滩病毒核蛋白及糖蛋白G1特异性单抗所识别,其分子量约97 kD;含S0.7G1嵌合基因之重组杆状病毒在昆虫细胞中表达的融合蛋白,只能被抗汉滩病毒核 蛋白特异性单抗所识别,其分子量约43kD.上述结果提示,G1S0.7嵌合基因可能在昆虫细胞 中表达出完整的具有生物学活性的融合蛋白,S0.7G1嵌和基因的昆虫细胞表达产物不完整 ,且生物学活性不如G1S0.7嵌合基因的表达产物. 相似文献
106.
Three Acid phosphatases (ACP) were isolated and characterized from the lysosomes of blood stream forms of Trypanosoma brucei by a combination of isopynic and differential centrifugation through Ficoll, organic solvent precipitation, ion exchange on DEAE cellulose 52 and size exclusion chromatography on Sephadex G-75 columns. The purified ACP emerged as three distinct peaks (ACP I, ACP II and ACP III) with high specific activities and they moved homogenously on 12% SDS-PAGE each as a single band with relative molecular weight of 36 kDa, 25 kDa and 45 kDa respectively. The purified enzymes were active at an optimum pH and temperature of 5.5 and 40 °C respectively. The enzyme activities appeared to be ACP because their activities were enhanced at low pH values and inhibited by the acid phosphatase inhibitor, sodium fluoride. ACP I and ACP II were sensitive to l-tartrate while ACP III was insensitive to l tartrate. The kinetic analysis of the purified enzyme (ACP I, ACP II and ACP III) determined using para-nitrophenylphosphate as substrate gave KM values of 0.2 mM, 0.15 mM and 0.5 mM. Monofunctional group sulfhydryl group inhibitors; HgCl2, and AgCl2 strongly inhibited the activity of ACP III and millimolar concentrations of dithiothreitol and iodoacetamide activated and inhibited the activity of the ACP III respectively, suggesting the involvement of thiol groups at the active site of the enzyme. Thus, differentiating it from ACP I and ACP II. The implication of these findings in relation to the pathology of trypanosomosis is discussed. 相似文献
107.
Cofilin蛋白功能及活性调节 总被引:2,自引:2,他引:2
Cofilin是普遍存在于真核细胞的一种肌动蛋白结合蛋白. Cofilin的基本功能是在细胞内结合和解聚F肌动蛋白(F-actin),其活性是通过磷酸化、去磷酸化、磷酸肌醇、pH改变等进行调节.cofilin介导了细胞内的信号途径,从而调节肌动蛋白骨架的重组,对肌肉形态发育起到重要作用.目前,在各种有机体中发现了许多特征性的cofilin蛋白同系物.其中鼠和人有2种cofilin蛋白:cofilin-1(non-muscle cofilin)和cofilin-2(muscle cofilin).本文根据目前对cofilin的研究结果,从cofilin蛋白结构、功能、活性调节、在肌肉发育中的作用及相关疾病等方面进行阐述. 相似文献
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109.
Zandbelt MM Vogelzangs J Van De Putte LB Van Venrooij WJ Van Den Hoogen FH 《Arthritis research & therapy》2004,6(1):R33-R38
The presence of anti-alpha-fodrin autoantibodies has been reported to be a highly specific and sensitive test for the diagnosis of Sj?gren's syndrome (SjS). We looked (in Nijmegen) for anti-alpha-fodrin, anti-Ro60, and anti-La autoantibodies in a cohort of 51 patients with rheumatic diseases (primary SjS [21], secondary SjS 6, rheumatoid arthritis [RA] 12, systemic lupus erythematosus [SLE] 6, and scleroderma 6) and in 28 healthy subjects, using ELISA, immunoblotting, and immunoprecipitation. The same samples were analyzed with an alternative anti-alpha-fodrin ELISA in Hanover. The Nijmegen ELISA of the sera from primary SjS showed sensitivities of 43% and 48% for IgA- and IgG-type anti-alpha-fodrin antibodies, respectively. The Hanover ELISA showed sensitivities of 38% and 10% for IgA- and IgG-type anti-alpha-fodrin antibodies, respectively. The ELISAs for alpha-fodrin showed six (Nijmegen) and four (Hanover) anti-alpha-fodrin-positive RA sera. IgA and IgG anti-fodrin antibodies were also present in four patients with secondary SjS. The sensitivities of Ro60 and La-antibodies in the Nijmegen ELISA were 67% and 62%, respectively. Unlike anti-alpha-fodrin antibodies, all anti-Ro60 and anti-La positive sera could be confirmed by immunoblotting or RNA immunoprecipitation. Thus, anti-Ro and anti-La autoantibodies were more sensitive than anti-alpha-fodrin autoantibodies in ELISA and were more frequently confirmed by other techniques. Anti-La antibodies appear to be more disease-specific than anti-alpha-fodrin antibodies, which are also found in RA sera. Therefore, the measurement of anti-alpha-fodrin autoantibodies does not add much to the diagnosis of Sj?gren's syndrome. 相似文献
110.
A Parish M Schwaederle G Daniels D Piccioni P Fanta R Schwab K Shimabukuro BA Parker T Helsten R Kurzrock 《Cell cycle (Georgetown, Tex.)》2015,14(13):2121-2128
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