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排序方式: 共有2045条查询结果,搜索用时 218 毫秒
941.
942.
Li Y Bögershausen N Alanay Y Simsek Kiper PO Plume N Keupp K Pohl E Pawlik B Rachwalski M Milz E Thoenes M Albrecht B Prott EC Lehmkühler M Demuth S Utine GE Boduroglu K Frankenbusch K Borck G Gillessen-Kaesbach G Yigit G Wieczorek D Wollnik B 《Human genetics》2011,130(6):715-724
Kabuki syndrome (KS) is one of the classical, clinically well-known multiple anomalies/mental retardation syndromes, mainly characterized by a very distinctive facial appearance in combination with additional clinical signs such as developmental delay, short stature, persistent fingerpads, and urogenital tract anomalies. In our study, we sequenced all 54 coding exons of the recently identified MLL2 gene in 34 patients with Kabuki syndrome. We identified 18 distinct mutations in 19 patients, 11 of 12 tested de novo. Mutations were located all over the gene and included three nonsense mutations, two splice-site mutations, six small deletions or insertions, and seven missense mutations. We compared frequencies of clinical symptoms in MLL2 mutation carriers versus non-carriers. MLL2 mutation carriers significantly more often presented with short stature and renal anomalies (p?=?0.026 and 0.031, respectively), and in addition, MLL2 carriers obviously showed more frequently a typical facial gestalt (17/19) compared with non-carriers (9/15), although this result was not statistically significant (p?=?0.1). Mutation-negative patients were subsequently tested for mutations in ten functional candidate genes (e.g. MLL, ASC2, ASH2L, and WDR5), but no convincing causative mutations could be found. Our results indicate that MLL2 is the major gene for Kabuki syndrome with a wide spectrum of de novo mutations and strongly suggest further genetic heterogeneity. 相似文献
943.
Gunari N Brewer LH Bennett SM Sokolova A Kraut ND Finlay JA Meyer AE Walker GC Wendt DE Callow ME Callow JA Bright FV Detty MR 《Biofouling》2011,27(2):137-149
Mixtures of n-octadecyltrimethoxysilane (C18, 1-5 mole-%), n-octyltriethoxysilane (C8) and tetraethoxysilane (TEOS) gave xerogel surfaces of varying topography. The 1:49:50 C18/C8/TEOS xerogel formed 100-400-nm-wide, 2-7-nm deep pores by AFM while coatings with?≥3% C18 were free of such features. Segregation of the coating into alkane-rich and alkane-deficient regions in the 1:49:50 C18/C8/TEOS xerogel was observed by IR microscopy. Immersion in ASW for 48?h gave no statistical difference in surface energy for the 1:49:50 C18/C8/TEOS xerogel and a significant increase for the 50:50 C8/TEOS xerogel. Settlement of barnacle cyprids and removal of juvenile barnacles, settlement of zoospores of the alga Ulva linza, and strength of attachment of 7-day sporelings were compared amongst the xerogel formulations. Settlement of barnacle cyprids was significantly lower in comparison to glass and polystyrene standards. The 1:49:50 and 3:47:50 C18/C8/TEOS xerogels were comparable to PDMSE with respect to removal of juvenile barnacles and sporeling biomass, respectively. 相似文献
944.
945.
Christian Niedworok Katharina R?ck Inga Kretschmer Till Freudenberger Nadine Nagy Tibor Szarvas Frank vom Dorp Henning Reis Herbert Rübben Jens W. Fischer 《PloS one》2013,8(11)
Background
Urothelial bladder cancer is the ninth most common cancer. Despite surgical and chemotherapeutic treatment the prognosis is still poor once bladder cancer progresses to a muscle-invasive state. Discovery of new diagnostic markers and pathophysiologic effectors might help to contribute to novel diagnostic and therapeutic options. The extracellular matrix microenvironment shaped by the extracellular matrix critically affects tumor cell and stroma cell functions. Therefore, aim of the present study was to assess the possible implication of the small leucine-rich proteoglycan biglycan in progression of human urothelial bladder cancer.Methods and Results
For this purpose tumor biopsies of 76 bladder cancer patients with different tumor stages (pTa, pT1-T4) were investigated with respect to biglycan expression and correlated with a long-term (10 years) clinical follow-up. Interestingly, higher biglycan mRNA expression was associated with higher tumor stages and muscle invasiveness. In vitro knock-down of endogenous biglycan in human urothelial carcinoma cells (J82 cells) increased proliferation, whereas addition of recombinant biglycan and overexpression of biglycan inhibited tumor cell proliferation. In line with this growth-inhibitory effect of biglycan, transplantation of J82 cells after knock-down of biglycan resulted in significantly increased growth of subcutaneous xenograft tumors in nude mice in vivo. Furthermore, treatment with two anti-proliferative, multi-receptor tyrosine kinase inhibitors—sunitinib and sorafenib—strongly upregulated biglycan expression. Collectively, the experimental data suggest that high biglycan expression is associated with reduced tumor cell proliferation. In accordance, Kaplan-Meier analysis revealed higher 10-year survival in patients with high biglycan mRNA expression in tumor biopsies.Conclusion
In conclusion, the present data suggest that biglycan is an endogenous inhibitor of bladder cancer cell proliferation that is upregulated in response to anti-proliferative tyrosine kinase inhibitors. In addition, high biglycan expression is associated with favorable prognosis. 相似文献946.
Rossi Sergio Schubert Nadine Brown Darren Gonzalez-Posada Alba Soares Marcelo O. 《Coral reefs (Online)》2020,39(2):433-449
Coral Reefs - Studies over the past decades indicate that octocorals are becoming the dominant group in some areas of the Caribbean. Yet, basic knowledge about the trophic ecology of these... 相似文献
947.
Nadine Ngayila Michel Botineau Michel Baudu Jean-Philippe Basly 《Ecological Indicators》2009,9(2):307-312
Aquatic plants can be a sensitive and cost effective route to understanding the effects of contaminants and assessing ecosystem health. Among the aquatic macrophytes, watermilfoil genus Myriophyllum could be used in ecological surveys as in situ biomonitors of water quality due to its ability to concentrate pollutants in their tissues and reflect the environmental pollution. The objectives of the present study were to evaluate the phytotoxicity of two heavy metals, Cu (essential micronutrient) and Cd (non-essential metal) alone or in mixture at realistic (low) concentration levels to a common European watermilfoil, Myriophyllum alterniflorum. ANOVA Kruskall–Wallis data indicate that effect of pH and mixture on copper or cadmium amounts in plants was statistically non significant. Correlation between variables was assessed using Spearman's rank order correlation. The main correlations were between: (i) time and node length, (ii) fresh mass and dry mass, (iii) chlorophyll A and carotenoids, and (iv) copper and cadmium in the mixture study. In addition to the Spearman correlations, data were analysed using the factor analysis. High positive loadings of mass (fresh weight and dry weight) along the factor 1 axis and high loadings (positive for copper and cadmium treatment, negative for the mixture) of plant growth (time, node length) along the factor 2 axis are evident. In conclusion, statistical estimate of the data revealed no strong significant relationships between the treatment (copper and cadmium in M. alterniflorum) and the somatic or photosynthetic endpoints studied. This lack of significant results could be explained by the low metal concentrations tested and this study failed to reproduce our first conclusions about the correlation between cadmium, chlorophyll A and carotenoids. 相似文献
948.
Nadine Hohmann Wei Weiwei Uta Dahmen Olaf Dirsch Andreas Deutsch Anja Voss-B?hme 《PloS one》2014,9(4)
The liver is a multi-functional organ that regulates major physiological processes and that possesses a remarkable regeneration capacity. After loss of functional liver mass the liver grows back to its original, individual size through hepatocyte proliferation and apoptosis. How does a single hepatocyte ‘know’ when the organ has grown to its final size? This work considers the initial growth phase of liver regeneration after partial hepatectomy in which the mass is restored. There are strong and valid arguments that the trigger of proliferation after partial hepatectomy is mediated through the portal blood flow. It remains unclear, if either or both the concentration of metabolites in the blood or the shear stress are crucial to hepatocyte proliferation and liver size control. A cell-based mathematical model is developed that helps discriminate the effects of these two potential triggers. Analysis of the mathematical model shows that a metabolic load and a hemodynamical hypothesis imply different feedback mechanisms at the cellular scale. The predictions of the developed mathematical model are compared to experimental data in rats. The assumption that hepatocytes are able to buffer the metabolic load leads to a robustness against short-term fluctuations of the trigger which can not be achieved with a purely hemodynamical trigger. 相似文献
949.
Nadine Proven?al Matthew J. Suderman Claire Guillemin Frank Vitaro Sylvana M. C?té Michael Hallett Richard E. Tremblay Moshe Szyf 《PloS one》2014,9(4)
Background
Chronic physical aggression (CPA) is characterized by frequent use of physical aggression from early childhood to adolescence. Observed in approximately 5% of males, CPA is associated with early childhood adverse environments and long-term negative consequences. Alterations in DNA methylation, a covalent modification of DNA that regulates genome function, have been associated with early childhood adversity.Aims
To test the hypothesis that a trajectory of chronic physical aggression during childhood is associated with a distinct DNA methylation profile during adulthood.Methods
We analyzed genome-wide promoter DNA methylation profiles of T cells from two groups of adult males assessed annually for frequency of physical aggression between 6 and 15 years of age: a group with CPA and a control group. Methylation profiles covering the promoter regions of 20 000 genes and 400 microRNAs were generated using MeDIP followed by hybridization to microarrays.Results
In total, 448 distinct gene promoters were differentially methylated in CPA. Functionally, many of these genes have previously been shown to play a role in aggression and were enriched in biological pathways affected by behavior. Their locations in the genome tended to form clusters spanning millions of bases in the genome.Conclusions
This study provides evidence of clustered and genome-wide variation in promoter DNA methylation in young adults that associates with a history of chronic physical aggression from 6 to 15 years of age. However, longitudinal studies of methylation during early childhood will be necessary to determine if and how this methylation variation in T cells DNA plays a role in early development of chronic physical aggression. 相似文献950.
Mélodie Aubart Delphine Gobert Fleur Aubart-Cohen Delphine Detaint Nadine Hanna Hyacintha d’Indya Janine-Sophie Lequintrec Philippe Renard Anne-Marie Vigneron Philippe Dieudé Jean-Pierre Laissy Pierre Koch Christine Muti Joelle Roume Veronica Cusin Bernard Grandchamp Laurent Gouya Eric LeGuern Thomas Papo Catherine Boileau Guillaume Jondeau 《PloS one》2014,9(5)