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51.
Zusammenfassung Die interne-Bestrahlung in kleinen Dosen vergrössert den 5-Hydroxytryptamin-Inhalt des zentralen Nervensystems der Ratte: Gehirnrinde, Dyencephalus, Hypothalamus, Geruchbulbe, Mittelhirn und Rückenmark. Bei Experimenten mit höheren Dosen (über 500 rad) sinkt der 5-Hydroxytryptamin-Gehalt.
This work has been carried out under a grant from the International Atomic Energy Agency, Vienna; contract No. 95 RB/1-RB/2. 相似文献
This work has been carried out under a grant from the International Atomic Energy Agency, Vienna; contract No. 95 RB/1-RB/2. 相似文献
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Monsuur AJ de Bakker PI Alizadeh BZ Zhernakova A Bevova MR Strengman E Franke L van't Slot R van Belzen MJ Lavrijsen IC Diosdado B Daly MJ Mulder CJ Mearin ML Meijer JW Meijer GA van Oort E Wapenaar MC Koeleman BP Wijmenga C 《Nature genetics》2005,37(12):1341-1344
Celiac disease is probably the best-understood immune-related disorder. The disease presents in the small intestine and results from the interplay between multiple genes and gluten, the triggering environmental factor. Although HLA class II genes explain 40% of the heritable risk, non-HLA genes accounting for most of the familial clustering have not yet been identified. Here we report significant and replicable association (P = 2.1 x 10(-6)) to a common variant located in intron 28 of the gene myosin IXB (MYO9B), which encodes an unconventional myosin molecule that has a role in actin remodeling of epithelial enterocytes. Individuals homozygous with respect to the at-risk allele have a 2.3-times higher risk of celiac disease (P = 1.55 x 10(-5)). This result is suggestive of a primary impairment of the intestinal barrier in the etiology of celiac disease, which may explain why immunogenic gluten peptides are able to pass through the epithelial barrier. 相似文献
54.
TRF2 is a telomere-binding protein that has a role in telomere protection. We generated mice that overexpress TRF2 in the skin. These mice had a severe phenotype in the skin in response to light, consisting of premature skin deterioration, hyperpigmentation and increased skin cancer, which resembles the human syndrome xeroderma pigmentosum. Keratinocytes from these mice were hypersensitive to ultraviolet irradiation and DNA crosslinking agents. The skin cells of these mice had marked telomere shortening, loss of the telomeric G-strand overhang and increased chromosomal instability. Telomere loss in these mice was mediated by XPF, a structure-specific nuclease involved in ultraviolet-induced damage repair and mutated in individuals with xeroderma pigmentosum. These findings suggest that TRF2 provides a crucial link between telomere function and ultraviolet-induced damage repair, whose alteration underlies genomic instability, cancer and aging. Finally, we show that a number of human skin tumors have increased expression of TRF2, further highlighting a role for TRF2 in skin cancer. 相似文献
55.
Resumen El epitelio de transición de cordero contiene actividad de sialidasa. Se demuestra que esta enzima se encuentra en lisosomas de este tejido y posee el pH óptimo ácido característico de enzimas lisosomales.
The technical assistance of MissE. Prado and Mr.L. Iwakawa is acknowledged. This investigation was supported by a grant of the Consejo Nacional de Investigaciones Cientificas y Técnicas of Argentina. 相似文献
The technical assistance of MissE. Prado and Mr.L. Iwakawa is acknowledged. This investigation was supported by a grant of the Consejo Nacional de Investigaciones Cientificas y Técnicas of Argentina. 相似文献
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Peña PV Davrazou F Shi X Walter KL Verkhusha VV Gozani O Zhao R Kutateladze TG 《Nature》2006,442(7098):100-103
58.
Ferres-Marco D Gutierrez-Garcia I Vallejo DM Bolivar J Gutierrez-Aviño FJ Dominguez M 《Nature》2006,439(7075):430-436
Cancer is both a genetic and an epigenetic disease. Inactivation of tumour-suppressor genes by epigenetic changes is frequently observed in human cancers, particularly as a result of the modifications of histones and DNA methylation. It is therefore important to understand how these damaging changes might come about. By studying tumorigenesis in the Drosophila eye, here we identify two Polycomb group epigenetic silencers, Pipsqueak and Lola, that participate in this process. When coupled with overexpression of Delta, deregulation of the expression of Pipsqueak and Lola induces the formation of metastatic tumours. This phenotype depends on the histone-modifying enzymes Rpd3 (a histone deacetylase), Su(var)3-9 and E(z), as well as on the chromodomain protein Polycomb. Expression of the gene Retinoblastoma-family protein (Rbf) is downregulated in these tumours and, indeed, this downregulation is associated with DNA hypermethylation. Together, these results establish a mechanism that links the Notch-Delta pathway, epigenetic silencing pathways and cell-cycle control in the process of tumorigenesis. 相似文献
59.
Oceanography: a phosphate alternative 总被引:1,自引:0,他引:1
Sañudo-Wilhelmy SA 《Nature》2006,439(7072):25-26
60.