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71.
Stella Aronov Saray Dover-Biterman Edith Suss-Toby Michael Shmoish Lea Duek Mordechai Choder 《The Journal of cell biology》2015,209(6):829-842
Association of messenger RNAs with large complexes such as processing bodies (PBs) plays a pivotal role in regulating their translation and decay. Little is known about other possible functions of these assemblies. Exposure of haploid yeast cells, carrying mating type “a,” to “α pheromone” stimulates polarized growth resulting in a “shmoo” projection; it also induces synthesis of “a pheromone,” encoded by MFA2. In this paper, we show that, in response to α pheromone, MFA2 mRNA is assembled with two types of granules; both contain some canonical PB proteins, yet they differ in size, localization, motility, and sensitivity to cycloheximide. Remarkably, one type is involved in mRNA transport to the tip of the shmoo, whereas the other—in local translation in the shmoo. Normal assembly of these granules is critical for their movement, localization, and for mating. Thus, MFA2 mRNAs are transported to the shmoo tip, in complex with PB-like particles, where they are locally translated. 相似文献
72.
Association of the fat mass and obesity‐associated gene risk allele,rs9939609A,and reward‐related brain structures 下载免费PDF全文
73.
Roberto Stella Giancarlo Biancotto Giorgio Arrigoni Federica Barrucci Roberto Angeletti Peter James 《Proteomics》2015,15(13):2332-2341
Despite the ban by the European Union, anabolic steroids might still be illicitly employed in bovine meat production. The surveillance of misuse of such potentially harmful molecules is necessary to guarantee consumers’ health. Analytical methods for drug residue control are based on LC‐MS/MS, but their efficacy can be hindered due to undetectable residual concentrations as a result of low‐dosage treatments. Screening methods based on the recognition of indirect biological effects of growth promoters’ administration, such as the alteration of protein expression, can improve the efficacy of surveillance. The present study was aimed at identifying modifications in the muscle protein expression pattern between bulls treated with an ear implant (Revalor‐XS®) containing trenbolone acetate (200 mg) and estradiol (40 mg), and untreated animals. The analysis of skeletal muscle was carried out using a tandem mass tags shotgun proteomics approach. We defined 28 candidate protein markers with a significantly altered expression induced by steroids administration. A subset of 18 candidate markers was validated by SRM and allowed to build a predictive model based on partial least square discriminant analysis. Our findings confirm the effectiveness of the proteomics approach as potential tool to overcome analytical limitations of drug residue monitoring. 相似文献
74.
Stefano Biffani Corrado Dimauro Nicolò Macciotta Attilio Rossoni Alessandra Stella Filippo Biscarini 《遗传、选种与进化》2015,47(1)
Background
SNP (single nucleotide polymorphisms) genotype data are increasingly available in cattle populations and, among other things, can be used to predict carriers of specific haplotypes. It is therefore convenient to have a practical statistical method for the accurate classification of individuals into carriers and non-carriers. In this paper, we present a procedure combining variable selection (i.e. the selection of predictive SNPs) and linear discriminant analysis for the identification of carriers of a haplotype on BTA19 (Bos taurus autosome 19) known to be associated with reduced cow fertility. A population of 3645 Brown Swiss cows and bulls genotyped with the 54K SNP-chip was available for the analysis.Results
The overall error rate for the prediction of haplotype carriers was on average very low (∼≤1%). The error rate was found to depend on the number of SNPs in the model and their density around the region of the haplotype on BTA19. The minimum set of SNPs to still achieve accurate predictions was 5, with a total test error rate of 1.59.Conclusions
The paper describes a procedure to accurately identify haplotype carriers from SNP genotypes in cattle populations. Very few misclassifications were observed, which indicates that this is a very reliable approach for potential applications in cattle breeding. 相似文献75.
Gianmauro Numico Antonella Cristofano Alessandro Mozzicafreddo Olga Elisabetta Cursio Pierfrancesco Franco Giulia Courthod Antonio Trogu Alessandra Malossi Mariella Cucchi Zuzana Sirotovà Maria Rosa Alvaro Anna Stella Fulvia Grasso Silvia Spinazzé Nicola Silvestris 《PloS one》2015,10(3)
Background
Cancer patients are frequently admitted to hospital due to acute conditions or refractory symptoms. This occurs through the emergency departments and requires medical oncologists to take an active role. The use of acute-care hospital increases in the last months of life.Patients and methods
We aimed to describe the admissions to a medical oncology inpatient service within a 16-month period with respect to patients and tumor characteristics, and the outcome of the hospital stay.Results
672 admissions of 454 patients were analysed. The majority of admissions were urgent (74.1%), and were due to uncontrolled symptoms (79.6%). Among the chief complaints, dyspnoea occurred in 15.7%, pain in 15.2%, and neurological symptoms in 14.5%. The majority of the hospitalizations resulted in discharge to home (60.6%); in 26.5% the patient died and in 11.0% was transferred to a hospice. Admissions due to symptoms correlated with a longer hospital stay and a higher incidence of in-hospital death.Conclusion
We suggest that hospital use is not necessarily a sign of inappropriately aggressive care: inpatient care is probably an unavoidable step in the cancer trajectory. Optimization of inpatient supportive procedures should be a specific task of modern medical oncology. 相似文献76.
Serotonin(4) (5-HT(4)) receptor agonists are putative antidepressants with a rapid onset of action 总被引:6,自引:0,他引:6
Lucas G Rymar VV Du J Mnie-Filali O Bisgaard C Manta S Lambas-Senas L Wiborg O Haddjeri N Piñeyro G Sadikot AF Debonnel G 《Neuron》2007,55(5):712-725
Current antidepressants are clinically effective only after several weeks of administration. Here, we show that serotonin(4) (5-HT(4)) agonists reduce immobility in the forced swimming test, displaying an antidepressant potential. Moreover, a 3 day regimen with such compounds modifies rat brain parameters considered to be key markers of antidepressant action, but that are observed only after 2-3 week treatments with classical molecules: desensitization of 5-HT(1A) autoreceptors, increased tonus on hippocampal postsynaptic 5-HT(1A) receptors, and enhanced phosphorylation of the CREB protein and neurogenesis in the hippocampus. In contrast, a 3 day treatment with the SSRI citalopram remains devoid of any effect on these parameters. Finally, a 3 day regimen with the 5-HT(4) agonist RS 67333 was sufficient to reduce both the hyperlocomotion induced by olfactory bulbectomy and the diminution of sucrose intake consecutive to a chronic mild stress. These findings point out 5-HT(4) receptor agonists as a putative class of antidepressants with a rapid onset of action. 相似文献
77.
Sally H. Vitali S. Alex Mitsialis Olin D. Liang Xiaoli Liu Angeles Fernandez-Gonzalez Helen Christou Xinqi Wu Francis X. McGowan Stella Kourembanas 《PloS one》2009,4(6)
Background
Hypoxia and pressure-overload induce heme oxygenase-1 (HO-1) in cardiomyocytes and vascular smooth muscle cells (VSMCs). HO-1−/− mice exposed to chronic hypoxia develop pulmonary arterial hypertension (PAH) with exaggerated right ventricular (RV) injury consisting of dilation, fibrosis, and mural thrombi. Our objective was to indentify the HO-1 product(s) mediating RV protection from hypoxic injury in HO-1−/− mice.Methodology/Principal Findings
HO-1−/− mice were exposed to seven weeks of hypoxia and treated with inhaled CO or biliverdin injections. CO reduced right ventricular systolic pressure (RVSP) and prevented hypoxic pulmonary arteriolar remodeling in both HO-1−/− and control mice. Biliverdin had no significant effect on arteriolar remodeling or RVSP in either genotype. Despite this, biliverdin prevented RV failure in the hypoxic HO-1−/− mice (0/14 manifested RV wall fibrosis or thrombus), while CO-treated HO-1−/− mice developed RV insults similar to untreated controls. In vitro, CO inhibited hypoxic VSMC proliferation and migration but did not prevent cardiomyocyte death from anoxia-reoxygenation (A-R). In contrast, bilirubin limited A-R-induced cardiomyocyte death but did not inhibit VSMC proliferation and migration.Conclusions/Significance
CO and bilirubin have distinct protective actions in the heart and pulmonary vasculature during chronic hypoxia. Moreover, reducing pulmonary vascular resistance may not prevent RV injury in hypoxia-induced PAH; supporting RV adaptation to hypoxia and preventing RV failure must be a therapeutic goal. 相似文献78.
The 1-deoxy-d-xylulose 5-phosphate synthase gene co-localizes with a major QTL affecting monoterpene content in grapevine 总被引:2,自引:0,他引:2
Juri Battilana Laura Costantini Francesco Emanuelli Federica Sevini Cinzia Segala Sergio Moser Riccardo Velasco Giuseppe Versini M. Stella Grando 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(4):653-669
Muscat flavor is a relevant trait both in winemaking and in fresh grape consumption. From a chemical point of view, it is
strongly related to the accumulation of monoterpenes in berries. However, knowledge of the genetic mechanisms underlying its
regulation is still limited. The objective of this study was to dissect the genetic determinism of aroma in grapevine by applying
the analysis of quantitative trait loci (QTL) and the candidate gene (CG) approach. Two F1 segregating progenies were evaluated through high-resolution gas chromatography–mass spectrometry (HRGC–MS) for the amounts
of individual monoterpenes over 3 and 2 years. In the Italia × Big Perlon cross 34 CGs, chosen according to gene ontology
(GO) terms, were placed on a complete map and tested for linkage with QTLs for linalool, nerol and geraniol levels. Two CGs
mapped within a QTL for linalool content on LG 10. A third one co-localized with a major QTL for the level of the three monoterpenes
on LG 5; this gene encodes 1-deoxy-d-xylulose 5-phosphate synthase (DXS), which is the first enzyme in the plastidial pathway of terpene biosynthesis. Depending
on these findings, we report the first in silico analysis of grapevine DXS genes based on the whole genome sequence. Further research on the functional significance of these associations might help
to understand the genetic control of Muscat flavor.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
J. Battilana and L. Costantini equally contributed to the work. 相似文献
79.
Abrogation of hepatocyte apoptosis and early appearance of liver dysplasia in ethanol-fed p53-deficient mice 总被引:1,自引:0,他引:1
Pani G Fusco S Colavitti R Borrello S Maggiano N Cravero AA Farré SM Galeotti T Koch OR 《Biochemical and biophysical research communications》2004,325(1):97-100
Ethanol consumption represents a major risk factor for cancer development, and a significant fraction of hepatocarcinomas arises in alcoholic liver cirrhosis. Increasing evidence indicates that ethanol acts as a tumor promoter on genetically initiated cells, by increasing the intracellular concentration of reactive oxygen species and promoting tissue necrosis/regeneration and cell proliferation. The tumor suppressor p53 restrains the expansion of carcinogen-initiated cells by inducing cell cycle arrest and apoptosis; accordingly, p53-deficient mice develop spontaneous and chemically induced neoplasms at a much higher frequency than normal mice. In normal mice exposed to a subacute (3 weeks) ethanol intoxication, a significant increase in the number of apoptotic hepatocytes was observed in concomitance with the up-regulation of the mitochondrial superoxide scavenger MnSOD, a reliable indicator of oxidative stress. Cell death occurred in the absence of liver inflammation and necrosis. Ethanol-induced hepatocyte apoptosis was completely abrogated in the p53 null background, suggesting that the tumor suppressor is necessary for hepatocyte death by ethanol. Accordingly, p53 -/- MEF were, unlike wild type cells, completely insensitive up to 0.5M ethanol in the culture medium. Strikingly, marked and widespread signs of dysplasia, with nuclear pleomorphisms and initial loss of normal architecture, heralding malignant transformation, were scored in all the mutant mice exposed to ethanol, but not in the control-fed littermates nor in ethanol-fed normal mice. These observations suggest that p53-dependent apoptosis restrains the tumorigenic effect of ethanol on liver cells, in agreement with the frequent loss of p53 function in HCC, and reveal an unexpected carcinogenic potential of alcohol which appears to be independent from the induction of cirrhosis and hepatocyte regeneration. 相似文献
80.
Liselotte W. Wijsman Anton J. M. de Craen Stella Trompet Jacobijn Gussekloo David J. Stott Nicolas Rodondi Paul Welsh J. Wouter Jukema Rudi G. J. Westendorp Simon P. Mooijaart 《PloS one》2013,8(3)