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81.
Nassa G Tarallo R Ambrosino C Bamundo A Ferraro L Paris O Ravo M Guzzi PH Cannataro M Baumann M Nyman TA Nola E Weisz A 《Proteomics》2011,11(1):159-165
Estrogen receptors α (ER-α) and β (ER-β) play distinct biological roles in onset and progression of hormone-responsive breast cancer, with ER-β exerting a modulatory activity on ER-α-mediated estrogen signaling and stimulation of cell proliferation by mechanisms still not fully understood. We stably expressed human ER-β fused to a tandem affinity purification-tag in estrogen-responsive MCF-7 cells and applied tandem affinity purification and nanoLC-MS/MS to identify the ER-β interactome of this cell type. Functional annotation by bioinformatics analyses of the 303 proteins that co-purify with ER-β from nuclear extracts identify several new molecular partners of this receptor subtype that represents nodal points of a large protein network controlling multiple processes and functions in breast cancer cells. 相似文献
82.
The peculiar heme pocket of the 2/2 hemoglobin of cold-adapted Pseudoalteromonas haloplanktis TAC125
Barry D. Howes Daniela Giordano Leonardo Boechi Roberta Russo Simona Mucciacciaro Chiara Ciaccio Federica Sinibaldi Maria Fittipaldi Marcelo A. Mart�� Dar��o A. Estrin Guido di Prisco Massimo Coletta Cinzia Verde Giulietta Smulevich 《Journal of biological inorganic chemistry》2011,16(2):299-311
The genome of the cold-adapted bacterium Pseudoalteromonas haloplanktis TAC125 contains multiple genes encoding three distinct monomeric hemoglobins exhibiting a 2/2 ??-helical fold. In the present work, one of these hemoglobins is studied by resonance Raman, electronic absorption and electronic paramagnetic resonance spectroscopies, kinetic measurements, and different bioinformatic approaches. It is the first cold-adapted bacterial hemoglobin to be characterized. The results indicate that this protein belongs to the 2/2 hemoglobin family, Group II, characterized by the presence of a tryptophanyl residue on the bottom of the heme distal pocket in position G8 and two tyrosyl residues (TyrCD1 and TyrB10). However, unlike other bacterial hemoglobins, the ferric state, in addition to the aquo hexacoordinated high-spin form, shows multiple hexacoordinated low-spin forms, where either TyrCD1 or TyrB10 can likely coordinate the iron. This is the first example in which both TyrCD1 and TyrB10 are proposed to be the residues that are alternatively involved in heme hexacoordination by endogenous ligands. 相似文献
83.
Luca Fontanesi Michela Colombo Lucia Tognazzi Emilio Scotti Luca Buttazzoni Stefania Dall’Olio Roberta Davoli Vincenzo Russo 《Molecular biology reports》2011,38(2):1425-1431
TBC1D1 [TBC1 (tre-2/USP6, BUB2, cdc16) domain family, member 1] is a Rab-GTPase-activating related protein implicated in regulating
the trafficking of glucose transporter 4 (GLUT4 or SLC2A4) storage vesicles to the cell surface in response to insulin and
AMPK-activating stimuli in skeletal muscle. Mutations in the human and mouse TBC1D1 genes confer risk of obesity or leanness. We identified five single nucleotide polymorphisms (SNPs) in the porcine TBC1D1 gene. One of them (FN677935:g.219G>A) was genotyped either by high resolution melting and PCR-RFLP analyses to study allele
frequencies in a few pig breeds and evaluate association with meat production and carcass traits in five groups of sib-tested
pigs of Italian Large White and Italian Duroc breeds. The g.219G>A SNP was associated (P < 0.05) with ham weight, back fat thickness and lean cuts content in Italian Large White and with visible intermuscular fat
in Italian Duroc pigs. 相似文献
84.
Roberta Baronio Samuel A. Danziger Linda V. Hall Kirsty Salmon G. Wesley Hatfield Richard H. Lathrop Peter Kaiser 《Nucleic acids research》2010,38(20):7079-7088
In vitro scanning mutagenesis strategies are valuable tools to identify critical residues in proteins and to generate proteins with modified properties. We describe the fast and simple All-Codon Scanning (ACS) strategy that creates a defined gene library wherein each individual codon within a specific target region is changed into all possible codons with only a single codon change per mutagenesis product. ACS is based on a multiplexed overlapping mutagenesis primer design that saturates only the targeted gene region with single codon changes. We have used ACS to produce single amino-acid changes in small and large regions of the human tumor suppressor protein p53 to identify single amino-acid substitutions that can restore activity to inactive p53 found in human cancers. Single-tube reactions were used to saturate defined 30-nt regions with all possible codon changes. The same technique was used in 20 parallel reactions to scan the 600-bp fragment encoding the entire p53 core domain. Identification of several novel p53 cancer rescue mutations demonstrated the utility of the ACS approach. ACS is a fast, simple and versatile method, which is useful for protein structure–function analyses and protein design or evolution problems. 相似文献
85.
Classical genetic studies discovered loss of genes from the ancient sex chromosome systems of several animals (genetic degeneration), and complete genome sequencing confirms that the heterogametic sex is hemizygous for most sex-linked genes. Genetic degeneration is thought to result from the absence of recombination between the sex chromosome pair (reviewed by [1]) and is very rapid after sex chromosome-autosome fusions in Drosophila [2-4]. Plant sex chromosome systems allow study of the time course of degeneration, because they evolved from a state wholly without sex chromosomes (rather than after a large genome region fused to a preexisting sex chromosome), and, in several taxa, recombination stopped very recently. However, despite increasing genetic and physical mapping of plant nonrecombining sex-determining regions [5-8], it remains very difficult to discover sex-linked genes, and it is unclear whether Y-linked genes are losing full function. We therefore developed a high-throughput method using RNA-Seq to identify sex linkage in Silene latifolia. Recombination suppression between this plant's XY sex chromosome pair started only about 10 million years ago [9]. Our approach identifies several hundred new sex-linked genes, and we show that this young Y chromosome retains many genes, yet these already have slightly reduced gene expression and are accumulating changes likely to reduce protein functions. 相似文献
86.
Roberta Ascrizzi Simonetta Maccioni Gianni Bedini Guido Flamini 《Plant biosystems》2019,153(4):538-543
Two populations of Stachys recta growing in Italy on ultramafic and calcareous soils have been studied for their essential oils. Although the yields were comparable, the composition of the essential oils differed significantly. Plants growing on ultramafic soil produced mainly non-terpene derivatives (55.7%), of which the most abundant ones were 1-octen-3-ol (38.2%) and (E)-3-hexen-1-ol (5.9%); the terpenes α-cadinol (6.1%) and δ-cadinene (5.6%) were also significantly represented. In contrast, the populations living on calcareous soil produced an essential oil dominated by terpenes (93.8%), with germacrene D (18.8%), β-caryophyllene (17.7%), 1,8-cineole (15.9%) and α-pinene (14.2%) among the main components. 相似文献
87.
Ígor B. Cursi Roberta Teixeira Silva Isabella Brasil Succi Andréa R. Bernardes-Engemann Rosane Orofino-Costa 《Mycopathologia》2013,175(1-2):75-82
Background
Onychomycosis by Neoscytalidium constitutes chronic infection of the nails, and its frequency has increased in recent decades. Currently, no effective standard treatment exists and literature data remain scarce. This work aimed to conduct a pilot project of combined treatment for this infection.Methods
Thirty patients were divided into three treatment groups: oral terbinafine plus ciclopirox nail lacquer twice a week; ciclopirox nail lacquer twice a week; and ciclopirox nail lacquer 5 days a week, all associated with nail abrasion when required, for 12 months, with 6 months posttreatment follow-up. Clinical and mycological criteria were used for evaluation.Results
Twenty-five patients completed the study. Significant clinical lesion reduction in disease occurred in all three treatment groups: 21 patients (84 %) entered the study with more than 50 % of diseased nail plate, at the end of treatment, and at 6-month follow-up, 84 and 96 %, respectively, presented less than 25 % nail lesion. Negative microscopy was observed in 36 % of the patients at the end of treatment and in 24 % of the patients at 6-month follow-up. At treatment completion (12 months), culture was negative in 21 patients (84 %) and in 18 (72 %) at follow-up. It was not possible to establish any clinical or mycological statistical differences between groups (p > 0.05). Global medical evaluation upon treatment completion revealed that one patient (4 %) presented complete cure, 8 (32 %) presented partial cure, 16 (64 %) presented therapeutic failure. At the end of follow-up period, 6 patients (24 %) were considered to have recurrence/reinfection.Conclusions
The results obtained at the 6-month period of follow-up showed marked improvement (96 % of clinical improvement and 72 % of negative culture) of the patients treated for onychomycosis caused by Neoscytalidium in the three tested groups with no statistical differences between them. Multicentric studies with greater number of patients enrolled are necessary to confirm these results. 相似文献88.
Jia LG Donnet C Bogaev RC Blatt RJ McKinney CE Day KH Berr SS Jones LR Moorman JR Sweadner KJ Tucker AL 《American journal of physiology. Heart and circulatory physiology》2005,288(4):H1982-H1988
Phospholemman (FXYD1), a 72-amino acid transmembrane protein abundantly expressed in the heart and skeletal muscle, is a major substrate for phosphorylation in the cardiomyocyte sarcolemma. Biochemical, cellular, and electrophysiological studies have suggested a number of possible roles for this protein, including ion channel modulator, taurine-release channel, Na(+)/Ca(2+) exchanger modulator, and Na-K-ATPase-associated subunit. We have generated a phospholemman-deficient mouse. The adult null mice exhibited increased cardiac mass, larger cardiomyocytes, and ejection fractions that were 9% higher by magnetic resonance imaging compared with wild-type animals. Notably, this occurred in the absence of hypertension. Total Na-K-ATPase activity was 50% lower in the phospholemman-deficient hearts. Expression (per unit of membrane protein) of total Na-K-ATPase was only slightly diminished, but expression of the minor alpha(2)-isoform, which has been specifically implicated in the control of contractility, was reduced by 60%. The absence of phospholemman thus results in a complex response, including a surprisingly large reduction in intrinsic Na-K-ATPase activity, changes in Na-K-ATPase isoform expression, increase in ejection fraction, and increase in cardiac mass. We hypothesize that a primary effect of phospholemman is to modulate the Na-K-ATPase and that its reduced activity initiates compensatory responses. 相似文献
89.
Central giant cell lesion of the jaws: study of CCND1 gene amplification and p16INK4a protein levels
Renato Luiz Maia Nogueira Mário Henrique Girão Faria Rafael Lima Verde Osterne Roberta Barroso Cavalcante Ronaldo Albuquerque Ribeiro Cassiano Francisco Weege Nonaka Silvia Helena Barem Rabenhorst 《Journal of molecular histology》2013,44(5):527-534
Central giant cell lesions (CGCLs) are uncommon benign jaw lesions with uncertain etiology and a variable clinical behavior. In neoplasms, alterations in molecules involved in the G1/S checkpoint are frequently found. Loss of p16INK4a expression or overexpression of cyclin D1 may stimulate cell proliferation. The purpose of this study was to analyze CCND1 gene amplification and the expression of p16INK4a in CGCLs. Structural analysis of the CCND1 was performed using chromogenic in situ hybridization. Immmunohistochemistry was used to identify p16INK4a protein levels. Statistical analysis correlated the two biomarkers with clinical behavior and between each other. Twenty-four lesions were included, being 11 aggressive and 13 non-aggressive. Moderate/high-level CCND1 amplification was found in 12 lesions. Also, immunoreactivity for p16INK4a was present in 12 cases, mainly in mononuclear cells. There was a significantly higher level of p16INK4a expression in mononuclear cells of non-aggressive lesions and lesions with moderate/high-level CCND1 amplification in mononuclear cells. It could be speculated that some CGCLs may develop as a true benign neoplasm. The higher expression of p16INK4a in non-aggressive lesions and in cases with moderate/high-level CCND1 amplification may show that these molecules have a role in CGCLs. 相似文献
90.
Summary Endoproteinase(s) was isolated from a freeze-dried powder of larvae of Ostrinia nubilalis using reverse micellar solutions. The inhibition of proteinase was studied in reverse micelles with commercial Bowman-Birk soybean trypsin inhibitor and three trypsin inhibitors recently isolated from ripe cruciferous seeds. 相似文献