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61.
A novel disorder caused by defective biosynthesis of N-linked oligosaccharides due to glucosidase I deficiency 总被引:11,自引:0,他引:11 下载免费PDF全文
De Praeter CM Gerwig GJ Bause E Nuytinck LK Vliegenthart JF Breuer W Kamerling JP Espeel MF Martin JJ De Paepe AM Chan NW Dacremont GA Van Coster RN 《American journal of human genetics》2000,66(6):1744-1756
Glucosidase I is an important enzyme in N-linked glycoprotein processing, removing specifically distal alpha-1,2-linked glucose from the Glc3Man9GlcNAc2 precursor after its en bloc transfer from dolichyl diphosphate to a nascent polypeptide chain in the endoplasmic reticulum. We have identified a glucosidase I defect in a neonate with severe generalized hypotonia and dysmorphic features. The clinical course was progressive and was characterized by the occurrence of hepatomegaly, hypoventilation, feeding problems, seizures, and fatal outcome at age 74 d. The accumulation of the tetrasaccharide Glc(alpha1-2)Glc(alpha1-3)Glc(alpha1-3)Man in the patient's urine indicated a glycosylation disorder. Enzymological studies on liver tissue and cultured skin fibroblasts revealed a severe glucosidase I deficiency. The residual activity was <3% of that of controls. Glucosidase I activities in cultured skin fibroblasts from both parents were found to be 50% of those of controls. Tissues from the patient subjected to SDS-PAGE followed by immunoblotting revealed strongly decreased amounts of glucosidase I protein in the homogenate of the liver, and a less-severe decrease in cultured skin fibroblasts. Molecular studies showed that the patient was a compound heterozygote for two missense mutations in the glucosidase I gene: (1) one allele harbored a G-->C transition at nucleotide (nt) 1587, resulting in the substitution of Arg at position 486 by Thr (R486T), and (2) on the other allele a T-->C transition at nt 2085 resulted in the substitution of Phe at position 652 by Leu (F652L). The mother was heterozygous for the G-->C transition, whereas the father was heterozygous for the T-->C transition. These base changes were not seen in 100 control DNA samples. A causal relationship between the alpha-glucosidase I deficiency and the disease is postulated. 相似文献
62.
The early MIS 3 (55–40 Kyr BP associated with Middle Palaeolithic archaeology) bird remains from Pin Hole, Creswell Crags, Derbyshire, England are analysed in the context of the new dating of the site’s stratigraphy. The analysis is restricted to the material from the early MIS 3 level of the cave because the upper fauna is now known to include Holocene material as well as that from the Late Glacial. The results of the analysis confirm the presence of the taxa, possibly unexpected for a Late Pleistocene glacial deposit including records such as Alpine swift, demoiselle crane and long-legged buzzard with southern and/or eastern distributions today. These taxa are accompanied by more expected ones such as willow ptarmigan /red grouse and rock ptarmigan living today in northern and montane areas. Finally, there are temperate taxa normally requiring trees for nesting such as wood pigeon and grey heron. Therefore, the result of the analysis is that the avifauna of early MIS 3 in England included taxa whose ranges today do not overlap making it a non-analogue community similar to the many steppe-tundra mammalian faunas of the time. The inclusion of more temperate and woodland taxa is discussed in the light that parts of northern Europe may have acted as cryptic northern refugia for some such taxa during the last glacial. These records showing former ranges of taxa are considered in the light of modern phylogeographic studies as these often assume former ranges without considering the fossil record of those taxa. In addition to the anomalous combination of taxa during MIS 3 living in Derbyshire, the individuals of a number of the taxa are different in size and shape to members of the species today probably due to the high carrying capacity of the steppe-tundra. 相似文献
63.
Vincenzo Forgetta Gary Leveque Joana Dias Deborah Grove Robert Lyons Jr. Suzanne Genik Chris Wright Sushmita Singh Nichole Peterson Michael Zianni Jan Kieleczawa Robert Steen Anoja Perera Doug Bintzler Scottie Adams Will Hintz Volker Jacobi Louis Bernier Roger Levesque Ken Dewar 《Journal of biomolecular techniques》2013,24(1):39-49
As part of the DNA Sequencing Research Group of the Association of Biomolecular Resource Facilities, we have tested the reproducibility of the Roche/454 GS-FLX Titanium System at five core facilities. Experience with the Roche/454 system ranged from <10 to >340 sequencing runs performed. All participating sites were supplied with an aliquot of a common DNA preparation and were requested to conduct sequencing at a common loading condition. The evaluation of sequencing yield and accuracy metrics was assessed at a single site. The study was conducted using a laboratory strain of the Dutch elm disease fungus Ophiostoma novo-ulmi strain H327, an ascomycete, vegetatively haploid fungus with an estimated genome size of 30–50 Mb. We show that the Titanium System is reproducible, with some variation detected in loading conditions, sequencing yield, and homopolymer length accuracy. We demonstrate that reads shorter than the theoretical minimum length are of lower overall quality and not simply truncated reads. The O. novo-ulmi H327 genome assembly is 31.8 Mb and is comprised of eight chromosome-length linear scaffolds, a circular mitochondrial conti of 66.4 kb, and a putative 4.2-kb linear plasmid. We estimate that the nuclear genome encodes 8613 protein coding genes, and the mitochondrion encodes 15 genes and 26 tRNAs. 相似文献
64.
Cullin 4 (Cul4), a member of the evolutionally conserved cullin protein family, serves as a scaffold to assemble multisubunit ubiquitin E3 ligase complexes. Cul4 interacts with the Ring finger-containing protein ROC1 through its C-terminal cullin domain and with substrate recruiting subunit(s) through its N-terminus. Previous studies have demonstrated that Cul4 E3 ligase ubiquitylates key regulators in cell cycle control and mediates their degradation through the proteasomal pathway, thus contributing to genome stability. Recent studies from several groups have revealed that Cul4 E3 ligase can target histones for ubiquitylation, and importantly, ubiquitylation of histones may facilitate the cellular response to DNA damage. Therefore, histone ubiquitylation by Cul4 E3 ligase constitutes a novel mechanism through which Cul4 regulates chromatin function and maintains genomic integrity. We outline these studies and suggest that histone ubiquitylation might play important roles in Cul4-regualted chromatin function including the cellular response to DNA damage and heterochromatin gene silencing. 相似文献
65.
S Weinstein R Emmanuel AM Jacobi A Abraham MA Behlke AG Sprague TI Novobrantseva A Nagler D Peer 《PloS one》2012,7(8):e43343
Mantle cell lymphoma is characterized by a genetic translocation results in aberrant overexpression of the CCND1 gene, which encodes cyclin D1. This protein functions as a regulator of the cell cycle progression, hence is considered to play an important role in the pathogenesis of the disease. In this study, we used RNA interference strategies to examine whether cyclin D1 might serve as a therapeutic target for mantle cell lymphoma. Knocking down cyclin D1 resulted in significant growth retardation, cell cycle arrest, and most importantly, induction of apoptosis. These results mark cyclin D1 as a target for mantle cell lymphoma and emphasize the therapeutic potential hidden in its silencing. 相似文献
66.
Fragmented and scrambled mitochondrial ribosomal RNA coding regions among green algae: a model for their origin and evolution 总被引:3,自引:1,他引:3
Mitochondrial ribosomal RNA coding regions in the only three green algal
taxa investigated to date are fundamentally different in that they are
continuous in Prototheca wickerhamii, but highly fragmented and scrambled
in Chlamydomonas reinhardtii and Chlamydomonas eugametos. To gain more
insight into the mode of evolution of fragmented and scrambled
mitochondrial ribosomal RNA (rRNA) genes within the green algal group, this
work (1) provides additional information on fragmentation patterns of
mitochondrial small- and large-subunit (SSU and LSU) rRNAs that strongly
supports the concept of a gradual increase in the extent of discontinuity
of mitochondrial rRNAs among chlorophycean green algae and (2) reports the
first example of fragmented and scrambled mitochondrial LSU rRNA coding
regions in a green algal taxon outside the Chlamydomonas group. The present
study (1) suggests that the scrambling of the mitochondrial rRNA coding
regions may have occurred early in the evolution of fragmented and
scrambled mitochondrial rRNA genes within the chlorophycean green algal
group, most likely in parallel with the fragmentation events, (2) proposes
recombination as a possible mechanism involved in the evolution of these
mitochondrial rRNA genes, and (3) presents a hypothetical pathway for
converting continuous mitochondrial rRNA genes into the highly fragmented
and scrambled rRNA coding regions of Chlamydomonas through a series of
recombinatorial events between short repeated sequences.
相似文献
67.
Jifeng Tang Samantha J Baldwin Jeanne ME Jacobs C Gerard van der Linden Roeland E Voorrips Jack AM Leunissen Herman van Eck Ben Vosman 《BMC bioinformatics》2008,9(1):374
Background
Simple Sequence Repeat (SSR) or microsatellite markers are valuable for genetic research. Experimental methods to develop SSR markers are laborious, time consuming and expensive. In silico approaches have become a practicable and relatively inexpensive alternative during the last decade, although testing putative SSR markers still is time consuming and expensive. In many species only a relatively small percentage of SSR markers turn out to be polymorphic. This is particularly true for markers derived from expressed sequence tags (ESTs). In EST databases a large redundancy of sequences is present, which may contain information on length-polymorphisms in the SSR they contain, and whether they have been derived from heterozygotes or from different genotypes. Up to now, although a number of programs have been developed to identify SSRs in EST sequences, no software can detect putatively polymorphic SSRs. 相似文献68.
Seppo AM Saari Kirsi H Juuti Joanna H Palojärvi Kirsi M Väisänen Riitta-Liisa Rajaniemi Leena E Saijonmaa-Koulumies 《Acta veterinaria Scandinavica》2009,51(1):40
Background
Demodex gatoi is unique among demodectic mites. It possesses a distinct stubby appearance, and, instead of residing in the hair follicles, it dwells in the keratin layer of the epidermis, causing a pruritic and contagious skin disease in cats. Little is known of the occurrence of D. gatoi in Europe or control of D. gatoi infestation. 相似文献69.
70.
Juan Manuel Herrero-Medrano Hendrik-Jan Megens Martien AM Groenen Mirte Bosse Miguel Pérez-Enciso Richard PMA Crooijmans 《BMC genomics》2014,15(1)