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151.
Enhancing Validity and Reliability Through Feedback-Driven Exploration: A Study in the Context of Conjoint Analysis 总被引:1,自引:1,他引:0
Irene Boesch Markus Schwaninger Michael Weber Roland W. Scholz 《Systemic Practice and Action Research》2013,26(3):217-238
This study proposes a research design for the enhancement of validity and reliability in conjoint analysis research. For this purpose, we are applying the concept of feedback-driven exploration to conjoint analysis and assess the proposed research design concerning its benefits and limitations in respect of validity and reliability of results. The article is of interest for the field of preference elicitation through stated preference methods, and for model validation in transdisciplinary research. By applying the principle of feedback-driven exploration, we allow for feedback loops between researchers, industry experts and survey participants in order to strengthen both validity and reliability. A multi-case study of the agricultural markets in Switzerland illustrates the functioning of the proposed research design. We find that feedback-driven exploration significantly increases validity and reliability by enhancing methodological rigor and implementing an error-correcting mechanism. Additionally, a better understanding of the underlying decision processes is supported by the design due to increased interaction between researchers, industry experts and market participants. 相似文献
152.
Molecular pathways driving disease-specific alterations of intestinal epithelial cells 总被引:1,自引:1,他引:0
Rocío López-Posadas Markus F. Neurath Imke Atreya 《Cellular and molecular life sciences : CMLS》2017,74(5):803-826
Due to the fact that chronic inflammation as well as tumorigenesis in the gut is crucially impacted by the fate of intestinal epithelial cells, our article provides a comprehensive overview of the composition, function, regulation and homeostasis of the gut epithelium. In particular, we focus on those aspects which were found to be altered in the context of inflammatory bowel diseases or colorectal cancer and also discuss potential molecular targets for a disease-specific therapeutic intervention. 相似文献
153.
Groesser L Herschberger E Ruetten A Ruivenkamp C Lopriore E Zutt M Langmann T Singer S Klingseisen L Schneider-Brachert W Toll A Real FX Landthaler M Hafner C 《Nature genetics》2012,44(7):783-787
Nevus sebaceous is a common congenital cutaneous malformation. Affected individuals may develop benign and malignant secondary tumors in the nevi during life. Schimmelpenning syndrome is characterized by the association of nevus sebaceous with extracutaneous abnormalities. We report that of 65 sebaceous nevi studied, 62 (95%) had mutations in the HRAS gene and 3 (5%) had mutations in the KRAS gene. The HRAS c.37G>C mutation, which results in a p.Gly13Arg substitution, was present in 91% of lesions. Nonlesional tissues from 18 individuals had a wild-type sequence, confirming genetic mosaicism. The HRAS c.37G>C mutation was also found in 8 of 8 associated secondary tumors. Mosaicism for HRAS c.37G>C and KRAS c.35G>A mutations was found in two individuals with Schimmelpenning syndrome. Functional analysis of HRAS c.37G>C mutant cells showed constitutive activation of the MAPK and PI3K-Akt signaling pathways. Our results indicate that nevus sebaceous and Schimmelpenning syndrome are caused by postzygotic HRAS and KRAS mutations. These mutations may predispose individuals to the development of secondary tumors in nevus sebaceous. 相似文献
154.
Broderick P Chubb D Johnson DC Weinhold N Försti A Lloyd A Olver B Ma YP Dobbins SE Walker BA Davies FE Gregory WA Child JA Ross FM Jackson GH Neben K Jauch A Hoffmann P Mühleisen TW Nöthen MM Moebus S Tomlinson IP Goldschmidt H Hemminki K Morgan GJ Houlston RS 《Nature genetics》2012,44(1):58-61
To identify risk variants for multiple myeloma, we conducted a genome-wide association study of 1,675 individuals with multiple myeloma and 5,903 control subjects. We identified risk loci for multiple myeloma at 3p22.1 (rs1052501 in ULK4; odds ratio (OR) = 1.32; P = 7.47 × 10(-9)) and 7p15.3 (rs4487645, OR = 1.38; P = 3.33 × 10(-15)). In addition, we observed a promising association at 2p23.3 (rs6746082, OR = 1.29; P = 1.22 × 10(-7)). Our study identifies new genomic regions associated with multiple myeloma risk that may lead to new etiological insights. 相似文献
155.
Regulation of flowering time: all roads lead to Rome 总被引:5,自引:0,他引:5
Plants undergo a major physiological change as they transition from vegetative growth to reproductive development. This transition
is a result of responses to various endogenous and exogenous signals that later integrate to result in flowering. Five genetically
defined pathways have been identified that control flowering. The vernalization pathway refers to the acceleration of flowering
on exposure to a long period of cold. The photoperiod pathway refers to regulation of flowering in response to day length
and quality of light perceived. The gibberellin pathway refers to the requirement of gibberellic acid for normal flowering
patterns. The autonomous pathway refers to endogenous regulators that are independent of the photoperiod and gibberellin pathways.
Most recently, an endogenous pathway that adds plant age to the control of flowering time has been described. The molecular
mechanisms of these pathways have been studied extensively in Arabidopsis
thaliana and several other flowering plants. 相似文献
156.
Oxidatively damaged biomolecules impair cellular functions and contribute to the pathology of a variety of diseases. RNA is
also attacked by reactive oxygen species, and oxidized RNA is increasingly recognized as an important contributor to neurodegenerative
complications in humans. Recently, evidence has accumulated supporting the notion that tRNA is involved in cellular responses
to various stress conditions. This review focuses on the intriguing consequences of oxidative modification of tRNA at the
structural and functional level. 相似文献
157.
Cambon-Thomsen A Thorisson GA Mabile L Andrieu S Bertier G Boeckhout M Cambon-Thomsen A Carpenter J Dagher G Dalgleish R Deschênes M di Donato JH Filocamo M Goldberg M Hewitt R Hofman P Kauffmann F Leitsalu L Lomba I Mabile L Melegh B Metspalu A Miranda L Napolitani F Oestergaard MZ Parodi B Pasterk M Reiche A Rial-Sebbag E Rivalle G Rochaix P Susbielle G Tarasova L Thomsen M Thorisson GA Zawati MH Zins M;BRIF workshop group 《Nature genetics》2011,43(6):503-504
158.
Hillmer AM Brockschmidt FF Hanneken S Eigelshoven S Steffens M Flaquer A Herms S Becker T Kortüm AK Nyholt DR Zhao ZZ Montgomery GW Martin NG Mühleisen TW Alblas MA Moebus S Jöckel KH Bröcker-Preuss M Erbel R Reinartz R Betz RC Cichon S Propping P Baur MP Wienker TF Kruse R Nöthen MM 《Nature genetics》2008,40(11):1279-1281
We carried out a genome-wide association study in 296 individuals with male-pattern baldness (androgenetic alopecia) and 347 controls. We then investigated the 30 best SNPs in an independent replication sample and found highly significant association for five SNPs on chromosome 20p11 (rs2180439 combined P = 2.7 x 10(-15)). No interaction was detected with the X-chromosomal androgen receptor locus, suggesting that the 20p11 locus has a role in a yet-to-be-identified androgen-independent pathway. 相似文献
159.
Since the reports three decades ago revealed that viruses are surprisingly abundant and efficiently infective in the ocean, marine viruses have generated a grea... 相似文献
160.
Zenker M Mayerle J Lerch MM Tagariello A Zerres K Durie PR Beier M Hülskamp G Guzman C Rehder H Beemer FA Hamel B Vanlieferinghen P Gershoni-Baruch R Vieira MW Dumic M Auslender R Gil-da-Silva-Lopes VL Steinlicht S Rauh M Shalev SA Thiel C Ekici AB Winterpacht A Kwon YT Varshavsky A Reis A 《Nature genetics》2005,37(12):1345-1350
Johanson-Blizzard syndrome (OMIM 243800) is an autosomal recessive disorder that includes congenital exocrine pancreatic insufficiency, multiple malformations such as nasal wing aplasia, and frequent mental retardation. We mapped the disease-associated locus to chromosome 15q14-21.1 and identified mutations, mostly truncating ones, in the gene UBR1 in 12 unrelated families with Johanson-Blizzard syndrome. UBR1 encodes one of at least four functionally overlapping E3 ubiquitin ligases of the N-end rule pathway, a conserved proteolytic system whose substrates include proteins with destabilizing N-terminal residues. Pancreas of individuals with Johanson-Blizzard syndrome did not express UBR1 and had intrauterine-onset destructive pancreatitis. In addition, we found that Ubr1(-/-) mice, whose previously reported phenotypes include reduced weight and behavioral abnormalities, had an exocrine pancreatic insufficiency, with impaired stimulus-secretion coupling and increased susceptibility to pancreatic injury. Our findings indicate that deficiency of UBR1 perturbs the pancreas' acinar cells and other organs, presumably owing to metabolic stabilization of specific substrates of the N-end rule pathway. 相似文献