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排序方式: 共有209条查询结果,搜索用时 93 毫秒
61.
62.
Tenesa A Farrington SM Prendergast JG Porteous ME Walker M Haq N Barnetson RA Theodoratou E Cetnarskyj R Cartwright N Semple C Clark AJ Reid FJ Smith LA Kavoussanakis K Koessler T Pharoah PD Buch S Schafmayer C Tepel J Schreiber S Völzke H Schmidt CO Hampe J Chang-Claude J Hoffmeister M Brenner H Wilkening S Canzian F Capella G Moreno V Deary IJ Starr JM Tomlinson IP Kemp Z Howarth K Carvajal-Carmona L Webb E Broderick P Vijayakrishnan J Houlston RS Rennert G Ballinger D Rozek L Gruber SB 《Nature genetics》2008,40(5):631-637
In a genome-wide association study to identify loci associated with colorectal cancer (CRC) risk, we genotyped 555,510 SNPs in 1,012 early-onset Scottish CRC cases and 1,012 controls (phase 1). In phase 2, we genotyped the 15,008 highest-ranked SNPs in 2,057 Scottish cases and 2,111 controls. We then genotyped the five highest-ranked SNPs from the joint phase 1 and 2 analysis in 14,500 cases and 13,294 controls from seven populations, and identified a previously unreported association, rs3802842 on 11q23 (OR = 1.1; P = 5.8 x 10(-10)), showing population differences in risk. We also replicated and fine-mapped associations at 8q24 (rs7014346; OR = 1.19; P = 8.6 x 10(-26)) and 18q21 (rs4939827; OR = 1.2; P = 7.8 x 10(-28)). Risk was greater for rectal than for colon cancer for rs3802842 (P < 0.008) and rs4939827 (P < 0.009). Carrying all six possible risk alleles yielded OR = 2.6 (95% CI = 1.75-3.89) for CRC. These findings extend our understanding of the role of common genetic variation in CRC etiology. 相似文献
63.
Finberg KE Heeney MM Campagna DR Aydinok Y Pearson HA Hartman KR Mayo MM Samuel SM Strouse JJ Markianos K Andrews NC Fleming MD 《Nature genetics》2008,40(5):569-571
Iron deficiency is usually attributed to chronic blood loss or inadequate dietary intake. Here, we show that iron deficiency anemia refractory to oral iron therapy can be caused by germline mutations in TMPRSS6, which encodes a type II transmembrane serine protease produced by the liver that regulates the expression of the systemic iron regulatory hormone hepcidin. These findings demonstrate that TMPRSS6 is essential for normal systemic iron homeostasis in humans. 相似文献
64.
Identification of the gene responsible for methylmalonic aciduria and homocystinuria, cblC type 总被引:10,自引:0,他引:10
Lerner-Ellis JP Tirone JC Pawelek PD Doré C Atkinson JL Watkins D Morel CF Fujiwara TM Moras E Hosack AR Dunbar GV Antonicka H Forgetta V Dobson CM Leclerc D Gravel RA Shoubridge EA Coulton JW Lepage P Rommens JM Morgan K Rosenblatt DS 《Nature genetics》2006,38(1):93-100
Methylmalonic aciduria and homocystinuria, cblC type (OMIM 277400), is the most common inborn error of vitamin B(12) (cobalamin) metabolism, with about 250 known cases. Affected individuals have developmental, hematological, neurological, metabolic, ophthalmologic and dermatologic clinical findings. Although considered a disease of infancy or childhood, some individuals develop symptoms in adulthood. The cblC locus was mapped to chromosome region 1p by linkage analysis. We refined the chromosomal interval using homozygosity mapping and haplotype analyses and identified the MMACHC gene. In 204 individuals, 42 different mutations were identified, many consistent with a loss of function of the protein product. One mutation, 271dupA, accounted for 40% of all disease alleles. Transduction of wild-type MMACHC into immortalized cblC fibroblast cell lines corrected the cellular phenotype. Molecular modeling predicts that the C-terminal region of the gene product folds similarly to TonB, a bacterial protein involved in energy transduction for cobalamin uptake. 相似文献
65.
de Bakker PI McVean G Sabeti PC Miretti MM Green T Marchini J Ke X Monsuur AJ Whittaker P Delgado M Morrison J Richardson A Walsh EC Gao X Galver L Hart J Hafler DA Pericak-Vance M Todd JA Daly MJ Trowsdale J Wijmenga C Vyse TJ Beck S Murray SS Carrington M Gregory S Deloukas P Rioux JD 《Nature genetics》2006,38(10):1166-1172
The proteins encoded by the classical HLA class I and class II genes in the major histocompatibility complex (MHC) are highly polymorphic and are essential in self versus non-self immune recognition. HLA variation is a crucial determinant of transplant rejection and susceptibility to a large number of infectious and autoimmune diseases. Yet identification of causal variants is problematic owing to linkage disequilibrium that extends across multiple HLA and non-HLA genes in the MHC. We therefore set out to characterize the linkage disequilibrium patterns between the highly polymorphic HLA genes and background variation by typing the classical HLA genes and >7,500 common SNPs and deletion-insertion polymorphisms across four population samples. The analysis provides informative tag SNPs that capture much of the common variation in the MHC region and that could be used in disease association studies, and it provides new insight into the evolutionary dynamics and ancestral origins of the HLA loci and their haplotypes. 相似文献
66.
Zanke BW Greenwood CM Rangrej J Kustra R Tenesa A Farrington SM Prendergast J Olschwang S Chiang T Crowdy E Ferretti V Laflamme P Sundararajan S Roumy S Olivier JF Robidoux F Sladek R Montpetit A Campbell P Bezieau S O'Shea AM Zogopoulos G Cotterchio M Newcomb P McLaughlin J Younghusband B Green R Green J Porteous ME Campbell H Blanche H Sahbatou M Tubacher E Bonaiti-Pellié C Buecher B Riboli E Kury S Chanock SJ Potter J Thomas G Gallinger S Hudson TJ Dunlop MG 《Nature genetics》2007,39(8):989-994
Using a multistage genetic association approach comprising 7,480 affected individuals and 7,779 controls, we identified markers in chromosomal region 8q24 associated with colorectal cancer. In stage 1, we genotyped 99,632 SNPs in 1,257 affected individuals and 1,336 controls from Ontario. In stages 2-4, we performed serial replication studies using 4,024 affected individuals and 4,042 controls from Seattle, Newfoundland and Scotland. We identified one locus on chromosome 8q24 and another on 9p24 having combined odds ratios (OR) for stages 1-4 of 1.18 (trend; P = 1.41 x 10(-8)) and 1.14 (trend; P = 1.32 x 10(-5)), respectively. Additional analyses in 2,199 affected individuals and 2,401 controls from France and Europe supported the association at the 8q24 locus (OR = 1.16, trend; 95% confidence interval (c.i.): 1.07-1.26; P = 5.05 x 10(-4)). A summary across all seven studies at the 8q24 locus was highly significant (OR = 1.17, c.i.: 1.12-1.23; P = 3.16 x 10(-11)). This locus has also been implicated in prostate cancer. 相似文献
67.
The spindle assembly checkpoint guards against chromosomal missegregation but does not induce arrest in oocytes that contain a few achiasmatic chromosomes (univalents). We followed the fate of univalents in oocytes during the first meiotic division, and although these preserved a meiotic kinetochore structure, they were also bi-oriented in a mitotic manner. The hybrid chromosomal configuration attained by univalents allows them to evade the spindle assembly checkpoint and contribute to aneuploidy in oocytes. 相似文献
68.
Mary Esther Gaulden 《Cellular and molecular life sciences : CMLS》1954,10(1):18-20
Zusammenfassung Extranukleares Chromatin, in der Form azentrischer Fragmente oder Teile ungebrochener Chromosomen, welche aus der Kernregion von Heuschreken-Neuroblasten herausragen, unterliegt nicht gleichzeitig mit dem intranuklearen Chromatin den telophasischen Veränderungen. Der oder die für die Telophaseveranderungen vor allem verantwortlichen Faktoren scheinen in der Kernregion der Zelle lokalisiert zu sein. Es werden Belege dafür gegeben, dass die Chromosomen während der Telophase sich bedeutend vergrössern, und es wird die Ansicht vertreten, dass im Spindelmaterial, zum Teil wenigstens, die für die Schwellung der Chromosomen verantwortliche Substanz zu sehen ist.
Work performed for Atomic Energy Commission under Contract No. W-7405-eng-26. 相似文献
Work performed for Atomic Energy Commission under Contract No. W-7405-eng-26. 相似文献
69.
Zusammenfassung Verwundung induziert Regeneration in entfernten Stellen bei männlichen und weiblichen Kaninchcn. Dies gilt für frühe Regenerationsstadien bei männlichen Tieren, während bei Weibchen die Regenerationswirkung mindestens 49 Tage anhält. Es wird vermutet, dass es sich um hormonale Einwirkungen infolge Stress handelt. 相似文献
70.
Zusammenfassung An der isolierten Kaninchenherzvorkammer verursacht Sauerstoffmangel Verminderung der diastolischen Erregbarkeit, Verlängerung der refraktären Phase sowie Herabsetzung der Kontraktionsfähigkeit. Herzmuskelflimmern wurde während dieser Anoxie nicht beobachtet. Sauerstoffzufuhr führte zu einer vollständigen Aufhebung der Anoxieauswirkung auf die absolute Refraktärperiode, zu einer teilweisen Aufhebung dieser Auswirkungen auf die Dauer der refraktären Gesamtpause, die diastolische Erregbarkeit und das Kontraktionsvermögen. 相似文献