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排序方式: 共有303条查询结果,搜索用时 15 毫秒
141.
142.
Hemang Parikh Zuoming Deng Meredith Yeager Joseph Boland Casey Matthews Jinping Jia Irene Collins Ariel White Laura Burdett Amy Hutchinson Liqun Qi Jennifer A. Bacior Victor Lonsberry Matthew J. Rodesch Jeffrey A. Jeddeloh Thomas J. Albert Heather A. Halvensleben Timothy T. Harkins Jiyoung Ahn Sonja I. Berndt Nilanjan Chatterjee Robert Hoover Gilles Thomas David J. Hunter Richard B. Hayes Stephen J. Chanock Laufey Amundadottir 《Human genetics》2010,127(1):91-99
Single nucleotide polymorphisms (SNPs) in the KLK3 gene on chromosome 19q13.33 are associated with serum prostate-specific antigen (PSA) levels. Recent genome wide association studies of prostate cancer have yielded conflicting results for association of the same SNPs with prostate cancer risk. Since the KLK3 gene encodes the PSA protein that forms the basis for a widely used screening test for prostate cancer, it is critical to fully characterize genetic variation in this region and assess its relationship with the risk of prostate cancer. We have conducted a next-generation sequence analysis in 78 individuals of European ancestry to characterize common (minor allele frequency, MAF >1%) genetic variation in a 56 kb region on chromosome 19q13.33 centered on the KLK3 gene (chr19:56,019,829–56,076,043 bps). We identified 555 polymorphic loci in the process including 116 novel SNPs and 182 novel insertion/deletion polymorphisms (indels). Based on tagging analysis, 144 loci are necessary to tag the region at an r 2 threshold of 0.8 and MAF of 1% or higher, while 86 loci are required to tag the region at an r 2 threshold of 0.8 and MAF >5%. Our sequence data augments coverage by 35 and 78% as compared to variants in dbSNP and HapMap, respectively. We observed six non-synonymous amino acid or frame shift changes in the KLK3 gene and three changes in each of the neighboring genes, KLK15 and KLK2. Our study has generated a detailed map of common genetic variation in the genomic region surrounding the KLK3 gene, which should be useful for fine-mapping the association signal as well as determining the contribution of this locus to prostate cancer risk and/or regulation of PSA expression. 相似文献
143.
Viviane N. Ngassam Wan-Chih Su Douglas L. Gettel Yawen Deng Zexu Yang Neven Wang-Tomic Varun P. Sharma Sowmya Purushothaman Atul N. Parikh 《Biophysical journal》2021,120(4):586-597
Single giant unilamellar vesicles (GUVs) rupture spontaneously from their salt-laden suspension onto solid surfaces. At hydrophobic surfaces, the GUVs rupture via a recurrent, bouncing ball rhythm. During each contact, the GUVs, rendered tense by the substrate interactions, porate, and spread a molecularly transformed motif of a monomolecular layer on the hydrophobic surface from the point of contact in a symmetric manner. The competition from pore closure, however, limits the spreading and produces a daughter vesicle, which re-engages with the substrate. At solid hydrophilic surfaces, by contrast, GUVs rupture via a distinctly different recurrent burst-heal dynamics; during burst, single pores nucleate at the contact boundary of the adhering vesicles, facilitating asymmetric spreading and producing a “heart”-shaped membrane patch. During the healing phase, the competing pore closure produces a daughter vesicle. In both cases, the pattern of burst-reseal events repeats multiple times, splashing and spreading the vesicular fragments as bilayer patches at the solid surface in a pulsatory manner. These remarkable recurrent dynamics arise, not because of the elastic properties of the solid surface, but because the competition between membrane spreading and pore healing, prompted by the surface-energy-dependent adhesion, determine the course of the topological transition. 相似文献
144.
Ulana Pogribna Xintian Yu Katrina Burson Yuxiang Zhou Robert E. Lasky Ponnada A. Narayana Nehal A. Parikh 《PloS one》2013,8(8)
Objective
To identify perinatal clinical antecedents of white matter microstructural abnormalities in extremely preterm infants.Methods
A prospective cohort of extremely preterm infants (N = 86) and healthy term controls (N = 16) underwent diffusion tensor imaging (DTI) at term equivalent age. Region of interest-based measures of white matter microstructure - fractional anisotropy and mean diffusivity - were quantified in seven vulnerable cerebral regions and group differences assessed. In the preterm cohort, multivariable linear regression analyses were conducted to identify independent clinical factors associated with microstructural abnormalities.Results
Preterm infants had a mean (standard deviation) gestational age of 26.1 (1.7) weeks and birth weight of 824 (182) grams. Compared to term controls, the preterm cohort exhibited widespread microstructural abnormalities in 9 of 14 regional measures. Chorioamnionitis, necrotizing enterocolitis, white matter injury on cranial ultrasound, and increasing duration of mechanical ventilation were adversely correlated with regional microstructure. Conversely, antenatal steroids, female sex, longer duration of caffeine therapy, and greater duration of human milk use were independent favorable factors. White matter injury on cranial ultrasound was associated with a five weeks or greater delayed maturation of the corpus callosum; every additional 10 days of human milk use were associated with a three weeks or greater advanced maturation of the corpus callosum.Conclusions
Diffusion tensor imaging is sensitive in detecting the widespread cerebral delayed maturation and/or damage increasingly observed in extremely preterm infants. In our cohort, it also aided identification of several previously known or suspected perinatal clinical antecedents of brain injury, aberrant development, and neurodevelopmental impairments. 相似文献145.
Talkowski ME Mullegama SV Rosenfeld JA van Bon BW Shen Y Repnikova EA Gastier-Foster J Thrush DL Kathiresan S Ruderfer DM Chiang C Hanscom C Ernst C Lindgren AM Morton CC An Y Astbury C Brueton LA Lichtenbelt KD Ades LC Fichera M Romano C Innis JW Williams CA Bartholomew D Van Allen MI Parikh A Zhang L Wu BL Pyatt RE Schwartz S Shaffer LG de Vries BB Gusella JF Elsea SH 《American journal of human genetics》2011,(4):551-563
Persons with neurodevelopmental disorders or autism spectrum disorder (ASD) often harbor chromosomal microdeletions, yet the individual genetic contributors within these regions have not been systematically evaluated. We established a consortium of clinical diagnostic and research laboratories to accumulate a large cohort with genetic alterations of chromosomal region 2q23.1 and acquired 65 subjects with microdeletion or translocation. We sequenced translocation breakpoints; aligned microdeletions to determine the critical region; assessed effects on mRNA expression; and examined medical records, photos, and clinical evaluations. We identified a single gene, methyl-CpG-binding domain 5 (MBD5), as the only locus that defined the critical region. Partial or complete deletion of MBD5 was associated with haploinsufficiency of mRNA expression, intellectual disability, epilepsy, and autistic features. Fourteen alterations, including partial deletions of noncoding regions not typically captured or considered pathogenic by current diagnostic screening, disrupted MBD5 alone. Expression profiles and clinical characteristics were largely indistinguishable between MBD5-specific alteration and deletion of the entire 2q23.1 interval. No copy-number alterations of MBD5 were observed in 7878 controls, suggesting MBD5 alterations are highly penetrant. We surveyed MBD5 coding variations among 747 ASD subjects compared to 2043 non-ASD subjects analyzed by whole-exome sequencing and detected an association with a highly conserved methyl-CpG-binding domain missense variant, p.79Gly>Glu (c.236G>A) (p = 0.012). These results suggest that genetic alterations of MBD5 cause features of 2q23.1 microdeletion syndrome and that this epigenetic regulator significantly contributes to ASD risk, warranting further consideration in research and clinical diagnostic screening and highlighting the importance of chromatin remodeling in the etiology of these complex disorders. 相似文献
146.
Comparative analysis of hemocyte phagocytosis between six species of arthropods as measured by flow cytometry 总被引:1,自引:0,他引:1
Phagocytosis of pathogens by hemocytes is a rapid-acting immune response and represents a primary means of limiting microbial infection in some species of arthropods. To survey the relative capacity of hemocyte phagocytosis as a function of the arthropod immune response, we examined the extent of phagocytosis among a wide taxonomic range of arthropod species including a decapod crustacean (Litopenaeus vannamei), three ixodid tick species (Amblyomma americanum, Dermacentor variabilis, and Ixodes scapularis), a mosquito species (Aedes aegypti), and a larval moth (Manduca sexta). Injected fluorescent beads were used as a model to elicit phagocytosis and were measured by flow cytometry, a technique provided in detail that may be adapted for use with any species of arthropod. The data indicated that smaller arthropods generally had a higher proportion of phagocytic cells than larger arthropods. 相似文献
147.
Haploid Saccharomyces cerevisiae cells growing on media lacking glucose but containing high concentrations of carbon sources such as fructose, galactose, raffinose, and ethanol exhibit enhanced agar invasion. These carbon sources also promote diploid filamentous growth in response to nitrogen starvation. The enhanced invasive and filamentous growth phenotypes are suppressed by the addition of glucose to the media and require the Snf1 kinase. Mutations in the PGI1 and GND1 genes encoding carbon source utilization enzymes confer enhanced invasive growth that is unaffected by glucose but requires active Snf1. Carbon source does not modulate FLO11 flocculin expression, but enhanced polarized bud site selection is necessary for invasion on certain carbon sources. Interestingly, deletion of SNF1 blocks invasion without affecting bud site selection. Snf1 is also required for formation of spokes and hubs in multicellular mats. To examine glucose repression of invasive growth more broadly, we performed genome-wide microarray expression analysis in wild-type cells growing on glucose and galactose, and snf1 Delta cells on galactose. SNF1 probably mediates glucose repression of multiple genes potentially involved in invasive and filamentous growth. FLO11-independent cell-cell attachment, cell wall integrity, and/or polarized growth are affected by carbon source metabolism. In addition, derepression of cell cycle genes and signalling via the cAMP-PKA pathway appears to depend upon SNF1 activity during growth on galactose. 相似文献
148.
Bianchi Matteo Marom Gil Ghosh Ram P. Rotman Oren M. Parikh Puja Gruberg Luis Bluestein Danny 《Biomechanics and modeling in mechanobiology》2019,18(2):435-451
Biomechanics and Modeling in Mechanobiology - Transcatheter aortic valve replacement (TAVR) has emerged as an effective alternative to conventional surgical valve replacement in high-risk patients... 相似文献
149.
Parikh RY Ramanathan R Coloe PJ Bhargava SK Patole MS Shouche YS Bansal V 《PloS one》2011,6(6):e21401
This study was performed to determine whether extracellular silver nanoparticles (AgNPs) production is a genus-wide phenotype associated with all the members of genus Morganella, or only Morganella morganii RP-42 isolate is able to synthesize extracellular Ag nanoparticles. To undertake this study, all the available Morganella isolates were exposed to Ag+ ions, and the obtained nanoproducts were thoroughly analyzed using physico-chemical characterization tools such as transmission electron microscopy (TEM), UV-visible spectrophotometry (UV-vis), and X-ray diffraction (XRD) analysis. It was identified that extracellular biosynthesis of crystalline silver nanoparticles is a unique biochemical character of all the members of genus Morganella, which was found independent of environmental changes. Significantly, the inability of other closely related members of the family Enterobacteriaceae towards AgNPs synthesis strongly suggests that AgNPs synthesis in the presence of Ag+ ions is a phenotypic character that is uniquely associated with genus Morganella. 相似文献
150.
Dezzutti CS Hendrix CW Marrazzo JM Pan Z Wang L Louissaint N Kalyoussef S Torres NM Hladik F Parikh U Mellors J Hillier SL Herold BC 《PloS one》2011,6(8):e23136