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321.
Goh YC Yap CT Huang BH Cronshaw AD Leung BP Lai PB Hart SP Dransfield I Ross JA 《Cellular and molecular life sciences : CMLS》2011,68(9):1581-1592
Heat-shock protein 60 (Hsp60) is a highly conserved stress protein which has chaperone functions in prokaryotes and mammalian
cells. Hsp60 is associated with the mitochondria and the plasma membrane through phosphorylation by protein kinase A, and
is incorporated into lipid membranes as a protein-folding chaperone. Its diverse intracellular chaperone functions include
the secretion of proteins where it maintains the conformation of precursors and facilitates their translocation through the
plasma membrane. We report here that Hsp60 is concentrated in apoptotic membrane blebs and translocates to the surface of
cells undergoing apoptosis. Hsp60 is also enriched in platelets derived from terminally differentiated megakaryocytes and
expressed at the surface of senescent platelets. Furthermore, the exposure of monocytic U937 cells to Hsp60 enhanced their
phagocytic activity. Our results suggests that externalized Hsp60 in apoptotic cells and senescent platelets influences events
subsequent to apoptosis, such as the clearance of apoptotic cells by phagocytes. 相似文献
322.
Sarcobatus Nees., a genus of North American halophytic shrubs, consists of 2 species: S. vermiculatus (Hook.) Torr. ( n = 18, 36), which is widespread in North America, and S. baileyi Cov ( n = 54), endemic to Nevada. Within S. vermiculatus , populations of n = 36 are widely distributed, whereas populations of n = 18 are found only in the Sonoran Desert, northern California, and northwestern Great Plains, locations at the periphery of the species range. Although the chromosome number of n = 18 is apparently a tetraploid, failure to form and n = 27 race intermediate to those of n = 18 and n = 36 suggests than n = 18 S. vermiculatus is of significant age and that it behaves chromosomally as a diploid. Sacrobatus has a long fossil pollen record and endured Pleistocene climatic extremes with little range displacement. 相似文献
323.
Genome-wide association study identifies a common variant associated with risk of endometrial cancer
Spurdle AB Thompson DJ Ahmed S Ferguson K Healey CS O'Mara T Walker LC Montgomery SB Dermitzakis ET;Australian National Endometrial Cancer Study Group Fahey P Montgomery GW Webb PM Fasching PA Beckmann MW Ekici AB Hein A Lambrechts D Coenegrachts L Vergote I Amant F Salvesen HB Trovik J Njolstad TS Helland H Scott RJ Ashton K Proietto T Otton G;National Study of Endometrial Cancer Genetics Group Tomlinson I Gorman M Howarth K Hodgson S Garcia-Closas M Wentzensen N Yang H Chanock S Hall P 《Nature genetics》2011,43(5):451-454
Endometrial cancer is the most common malignancy of the female genital tract in developed countries. To identify genetic variants associated with endometrial cancer risk, we performed a genome-wide association study involving 1,265 individuals with endometrial cancer (cases) from Australia and the UK and 5,190 controls from the Wellcome Trust Case Control Consortium. We compared genotype frequencies in cases and controls for 519,655 SNPs. Forty seven SNPs that showed evidence of association with endometrial cancer in stage 1 were genotyped in 3,957 additional cases and 6,886 controls. We identified an endometrial cancer susceptibility locus close to HNF1B at 17q12 (rs4430796, P = 7.1 × 10(-10)) that is also associated with risk of prostate cancer and is inversely associated with risk of type 2 diabetes. 相似文献
324.
Goudie DR D'Alessandro M Merriman B Lee H Szeverényi I Avery S O'Connor BD Nelson SF Coats SE Stewart A Christie L Pichert G Friedel J Hayes I Burrows N Whittaker S Gerdes AM Broesby-Olsen S Ferguson-Smith MA Verma C Lunny DP Reversade B Lane EB 《Nature genetics》2011,43(4):365-369
Multiple self-healing squamous epithelioma (MSSE), also known as Ferguson-Smith disease (FSD), is an autosomal-dominant skin cancer condition characterized by multiple squamous-carcinoma-like locally invasive skin tumors that grow rapidly for a few weeks before spontaneously regressing, leaving scars. High-throughput genomic sequencing of a conservative estimate (24.2 Mb) of the disease locus on chromosome 9 using exon array capture identified independent mutations in TGFBR1 in three unrelated families. Subsequent dideoxy sequencing of TGFBR1 identified 11 distinct monoallelic mutations in 18 affected families, firmly establishing TGFBR1 as the causative gene. The nature of the sequence variants, which include mutations in the extracellular ligand-binding domain and a series of truncating mutations in the kinase domain, indicates a clear genotype-phenotype correlation between loss-of-function TGFBR1 mutations and MSSE. This distinguishes MSSE from the Marfan syndrome-related disorders in which missense mutations in TGFBR1 lead to developmental defects with vascular involvement but no reported predisposition to cancer. 相似文献
325.
326.
Widschwendter M Fiegl H Egle D Mueller-Holzner E Spizzo G Marth C Weisenberger DJ Campan M Young J Jacobs I Laird PW 《Nature genetics》2007,39(2):157-158
Embryonic stem cells rely on Polycomb group proteins to reversibly repress genes required for differentiation. We report that stem cell Polycomb group targets are up to 12-fold more likely to have cancer-specific promoter DNA hypermethylation than non-targets, supporting a stem cell origin of cancer in which reversible gene repression is replaced by permanent silencing, locking the cell into a perpetual state of self-renewal and thereby predisposing to subsequent malignant transformation. 相似文献
327.
Broderick P Carvajal-Carmona L Pittman AM Webb E Howarth K Rowan A Lubbe S Spain S Sullivan K Fielding S Jaeger E Vijayakrishnan J Kemp Z Gorman M Chandler I Papaemmanuil E Penegar S Wood W Sellick G Qureshi M Teixeira A Domingo E Barclay E Martin L Sieber O;CORGI Consortium Kerr D Gray R Peto J Cazier JB Tomlinson I Houlston RS 《Nature genetics》2007,39(11):1315-1317
To identify risk variants for colorectal cancer (CRC), we conducted a genome-wide association study, genotyping 550,163 tag SNPs in 940 individuals with familial colorectal tumor (627 CRC, 313 advanced adenomas) and 965 controls. We evaluated selected SNPs in three replication sample sets (7,473 cases, 5,984 controls) and identified three SNPs in SMAD7 (involved in TGF-beta and Wnt signaling) associated with CRC. Across the four sample sets, the association between rs4939827 and CRC was highly statistically significant (P(trend) = 1.0 x 10(-12)). 相似文献
328.
通过对华北克拉通不同陆核斜长角闪岩类氧同位素组成测试和分析,表明:(ⅰ) 来自不同陆核的岩石氧同位素数据所构成的演化线都平行于地月演化线,说明这些陆核演化的母体属于太阳系物质;(ⅱ) 不同陆核的氧同位素组成演化线斜率相近,截距不同,说明华北克拉通太古宙不同陆核起源于氧同位素组成不均一的古地幔源. 相似文献
329.
介绍了一种基于尺蠖运动原理的能实现快速转弯的微小机器人系统,并对机器人进行了设计和制作,组装了实验用机器人样机,通过AT89C52单片机及其外围驱动控制电路对机器人行走和位置信号的产生进行控制,并通过二维PSD对微机器人的三维位置进行检测,取得了与理论一致的结果.实现了对该机器人的行走运动和位置检测控制的功能,为对该类机器人的进一步研究提供了一个新的思路. 相似文献
330.
以溯河洄游为特征的青海湖裸鲤是青海湖鱼类的优势种,但其洄游行为还知之甚少.利用高分辨率SHRIMPⅡ离子探针和激光剥蚀高分辨多接收电感耦合等离子体质谱仪(LA-MC-ICP-MS)分别测定了青海湖裸鲤微耳石轮纹中的氧和锶(O-Sr)同位素组成.结果表明,微耳石成长带中较低的δ~(18)O记录了青海湖裸鲤春夏时期所洄游的河水化学信息;将δ~(18)O与~(87)Sr/~(86)Sr同位素组成相结合,微耳石轮纹的同位素组成明确指示了多数个体可能更倾向于固定的河流洄游产卵.这一结果对于认识青海湖裸鲤的洄游习性以及鱼类保护和管理有重要的意义. 相似文献