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101.
目的:探讨原发性口腔鳞癌患者组织和血清中内皮抑素表达及与肿瘤分期、分级的关系。方法:采用免疫组化方法检测36例口腔鳞癌和12例正常口腔粘膜组织中内皮抑素表达情况。ELISA法检测36例口腔鳞癌患者术前血清内皮抑素水平,14例健康者血清做对照。结果:内皮抑素主要见于肿瘤组织细胞质。正常口腔粘膜中内皮抑素表达率为7.15%,口腔鳞癌组织中内皮抑素阳性率为76.44%,其中G1、G2、G3级阳性率分别为47.21%、79.17%、90.90%,病理分级间比较差异有统计学意义(P<0.05)。口腔鳞癌患者血清中内皮抑素水平(49.62±1.72)ng/mL显著高于健康对照者(5.60±0.37)ng/mL(P<0.05),TNM分期III、IV期肿瘤患者血清内皮抑素水平显著高于I和II期(P<0.05)。结论:口腔鳞癌患者组织和血清中内皮抑素表达显著升高,并与肿瘤分期、分级相关,检测内皮抑素表达有助于判断口腔鳞癌恶性程度。  相似文献   
102.
Magnolia grandiflora is an important medicinal,ornamental and horticultural plant species.The chloroplast(cp) genome of M.grandiflora was sequenced using a 454 sequencing platform and the genome structure was compared with other related species.The complete cp genome of M.grandiflora was 159623 bp in length and contained a pair of inverted repeats(IR) of 26563 bp separated by large and small single copy(LSC,SSC) regions of 87757 and 18740 bp,respectively.A total of 129 genes were successfully annotated,18 of which included introns.The identity,number and GC content of M.grandiflora cp genes were similar to those of other Magnoliaceae species genomes.Analysis revealed 218 simple sequence repeat(SSR) loci,most composed of A or T,contributing to a bias in base composition.The types and abundances of repeat units in Magnoliaceae species were relatively conserved and these loci will be useful for developing M.grandiflora cp genome vectors.In addition,results indicated that the cp genome size in Magnoliaceae species and the position of the IR border were closely related to the length of the ycf1 gene.Phylogenetic analyses based on 66 shared genes from 30 species using maximum parsimony(MP) and maximum likelihood(ML) methods provided strong support for the phylogenetic position of Magnolia.The availability of the complete cp genome sequence of M.grandiflora provides valuable information for breeding of desirable varieties,cp genetic engineering,developing useful molecular markers and phylogenetic analyses in Magnoliaceae.  相似文献   
103.
Personalized medicine aims to utilize genomic information about patients to tailor treatment.Gene replacement therapy for rare genetic disorders is perhaps the most extreme form of personalized medicine,in that the patients’ genome wholly determines their treatment regimen.Gene therapy for retinal disorders is poised to become a clinical reality.The eye is an optimal site for gene therapy due to the relative ease of precise vector delivery,immune system isolation,and availability for monitoring of any potential damage or side effects.Due to these advantages,clinical trials for gene therapy of retinal diseases are currently underway.A necessary precursor to such gene therapies is accurate molecular diagnosis of the mutation(s) underlying disease.In this review,we discuss the application of Next Generation Sequencing(NGS) to obtain such a diagnosis and identify disease causing genes,using retinal disorders as a case study.After reviewing ocular gene therapy,we discuss the application of NGS to the identification of novel Mendelian disease genes.We then compare current,array based mutation detection methods against next NGS-based methods in three retinal diseases:Leber’s Congenital Amaurosis,Retinitis Pigmentosa,and Stargardt’s disease.We conclude that next-generation sequencing based diagnosis offers several advantages over array based methods,including a higher rate of successful diagnosis and the ability to more deeply and efficiently assay a broad spectrum of mutations.However,the relative difficulty of interpreting sequence results and the development of standardized,reliable bioinformatic tools remain outstanding concerns.In this review,recent advances NGS based molecular diagnoses are discussed,as well as their implications for the development of personalized medicine.  相似文献   
104.
Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from China, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.  相似文献   
105.
From 2011 to 2012, we collected Scutellonema commune from the rhizosphere soil of coconut(cocos nucifera L.) and Scutellonema magniphasma from the rhizosphere soil of Rosa chinensis in Shenyang, China. S. commune was characterized by rounded scutella, which was varied from two annules anterior to the anus and five annules posterior. The lateral field was not areolated at the level of scutella. S. magniphasma was characterized by varying scutellum, about 7.0 μm in diameter, in position from four annules posterior to four annules anterior to the anus, and areolated at the level of the scutellum.  相似文献   
106.
In order to precisely recognize and karyotype Brassica napus L. chromosomes, C0t-1 DNA was extracted from its genomic DNA, labeled with biotin-1 1-dUTP and in situ hybridized. The hybridized locations were detected by Cy3-conjugated streptavidin. Specific fluorescence in situ hybridization (FISH) signal bands were detected on all individual chromosome pairs. Each chromosome pair showed specific banding patterns. The B. napus karyotype has been constructed, for the first time, on the basis of both Cot-1 DNA FISH banding patterns and chromosome morphology.  相似文献   
107.
The spatial heterogeneity of DTPA-extractable zinc in the cultivated soils of Shenyang suburbs in Liaoning Province of China was investigated, and its map was drawn by the methods of geostatistics combined with geographic information system. The data of soil DTPA-extractable zinc fitted normal distribution after logarithm transformation, and its semivariogram fitted a spherical model. The semivariogram indicated that the spatial dependence of soil DTPA-extractable zinc content was moderate, with the spatial dependence range of 1.69 km and the fractal dimension of 1.96. Stochastic factors contributed to 49.9% of the spatial variability, while structural factors contributed to 50.1% of it. The spatial heterogeneity of soil DTPA-extractable zinc shown by a kriged interpolation map was deeply influenced by stochastic factors such as city pollution, land use pattern and crop distributions. For example, the average content of Zn in vegetable garden soils was 2.5-4 times as much as in their originated soils, an  相似文献   
108.
固化技术在农村河道生态护岸中的应用   总被引:5,自引:0,他引:5  
基于自主开发的固化剂,采用建筑垃圾固化桩(+植被)和土壤整体固化(+植草)技术对上海市田山庄村河道实施了护岸工程,并结合其他生态工程技术对村中污塘进行了生态重建.结果表明:由建筑垃圾制成的固化桩的抗压强度高达73 MPa,具有一定孔隙率,且硬化快、干缩小,符合生态安全性要求,在添加抗冻剂后固化桩可在-18 ℃时使用;固化桩护岸的强度较高、土壤抗侵蚀能力较强、具有较好的水力通透性,其土壤湿度与裸露河岸基本一致,对植物根系生长无明显影响;土壤整体固化后,其表面抗剪切强度比裸露河岸增加了50倍,土壤流失量仅为裸露河岸的5%;在工程实施后第10天,固化面上狗牙根草皮中部分根系开始向固化土中伸展,1个月后60%的根系深入土中,11个月后狗牙根草与固化土融为一体.固化技术与植被重建相结合,既可以满足河岸稳定性的要求,也有助于重建河岸生境.  相似文献   
109.
 在全面调查大盘山国家级自然保护区香果树(Emmenopterys henryi)分布的基础上, 设置了4个海拔段(A1: 550 ~ 650 m, A2: 680 ~ 770 m, A3: 810 ~ 900 m, A4: 970 ~ 1 100 m), 对不同海拔段内香果树的生理生态特性进行研究, 结果显示, 叶绿素a (Chla)、叶绿素b (Chlb)和总叶绿素(Chl(a+b))含量均随着海拔的上升而减小, 高海拔A4与低海拔A1相比, Chla、Chlb和Chl(a+b)含量分别下降了21.32%、31.53%和24.96%, 差异均达到显著水平。分析认为, 主要是由于相对较强的光照以及干旱胁迫的增强所致。同样, 比叶面积(SLA)也随着海拔的上升而减小, A4与A1相比下降了27.55%, 差异达到显著水平。丙二醛(MDA)含量和质膜透性(MP)变化较为一致, 两者均在A3处达到最低水平, 在A4处达到最高, 说明在A3受到的伤害最小而在A4受到的伤害最大; 脯氨酸(Pro)和抗坏血酸(AsA)含量先升高再降低, 在A3处则均达到最高, 与A1相比分别增加了139.33%和10.60%; 酶保护系统中的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性在A1均最小, 随着海拔的升高, 其活性变化则不太一致: SOD活性一直增加, POD、CAT和APX活性虽然都是先增加后减小, 但POD和APX在A3达到最高, CAT则是在A2最高。非酶类保护物质含量的增加和酶活性的增强有利于清除细胞内的活性氧, 维持细胞膜的稳定性, 从而保证植物的正常生长。综合此次实验结果表明, 在中海拔(810~900 m)比较适合香果树的生长, 而高海拔(970~1 100 m)则不适合香果树的生长。  相似文献   
110.
目的评价全自动血培养仪BacT/Aler3D的临床应用情况。方法对BacT/Aler3D全自动血培养仪检测的1853份标本,其检出的阳性率、病原菌种类及阳性检出时间进行了评估。结果1853份血培养分离出病原菌189株,阳性率为10.2%,分离出病原菌23种,最快检出时间为2h,24h以内阳性率为68.5%,48h内阳性率为87.3%,72h以内阳性率为92.3%。结论BacT/Aler3D全自动血培养仪提高血培养的阳性率,检出的细菌种类多,污染机会少,缩短阳性检出时间,而且操作简便,结果快速、准确。  相似文献   
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