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991.
Su Yon Jung Mara Z. Vitolins Jenifer Fenton Alexis C. Frazier-Wood Stephen D. Hursting Shine Chang 《PloS one》2015,10(3)
Purpose
Risk factors for obesity and weight gain are typically evaluated individually while “adjusting for” the influence of other confounding factors, and few studies, if any, have created risk profiles by clustering risk factors. We identified subgroups of postmenopausal women homogeneous in their clustered modifiable and non-modifiable risk factors for gaining ≥ 3% weight.Methods
This study included 612 postmenopausal women 50–79 years old, enrolled in an ancillary study of the Women''s Health Initiative Observational Study between February 1995 and July 1998. Classification and regression tree and stepwise regression models were built and compared.Results
Of 27 selected variables, the factors significantly related to ≥ 3% weight gain were weight change in the past 2 years, age at menopause, dietary fiber, fat, alcohol intake, and smoking. In women younger than 65 years, less than 4 kg weight change in the past 2 years sufficiently reduced risk of ≥ 3% weight gain. Different combinations of risk factors related to weight gain were reported for subgroups of women: women 65 years or older (essential factor: < 9.8 g/day dietary factor), African Americans (essential factor: currently smoking), and white women (essential factor: ≥ 5 kg weight change for the past 2 years).Conclusions
Our findings suggest specific characteristics for particular subgroups of postmenopausal women that may be useful for identifying those at risk for weight gain. The study results may be useful for targeting efforts to promote strategies to reduce the risk of obesity and weight gain in subgroups of postmenopausal women and maximize the effect of weight control by decreasing obesity-relevant adverse health outcomes. 相似文献992.
Kim Heang Ly Alexis Régent Elsa Molina Sofiane Saada Philippe Sindou Claire Le-Jeunne Antoine Brézin Véronique Witko-Sarsat Fran?ois Labrousse Pierre-Yves Robert Philippe Bertin Jean-Louis Bourges Anne-Laure Fauchais Elisabeth Vidal Luc Mouthon Marie-Odile Jauberteau 《Arthritis research & therapy》2014,16(6)
Introduction
Giant cell arteritis (GCA) is characterized by intimal hyperplasia leading to ischaemic manifestations that involve large vessels. Neurotrophins (NTs) and their receptors (NTRs) are protein factors for growth, differentiation and survival of neurons. They are also involved in the migration of vascular smooth muscle cells (VSMCs). Our aim was to investigate whether NTs and NTRs are involved in vascular remodelling of GCA.Methods
We included consecutive patients who underwent a temporal artery biopsy for suspected GCA. We developed an enzymatic digestion method to obtain VSMCs from smooth muscle cells in GCA patients and controls. Neurotrophin protein and gene expression and functional assays were studied from these VSMCs. Neurotrophin expression was also analysed by immunohistochemistry in GCA patients and controls.Results
Whereas temporal arteries of both GCA patients (n = 22) and controls (n = 21) expressed nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase B (TrkB) and sortilin, immunostaining was more intense in GCA patients, especially in the media and intima, while neurotrophin-3 (NT-3) and P75 receptor (P75NTR) were only detected in TA from GCA patients. Expression of TrkB, a BDNF receptor, was higher in GCA patients with ischaemic complications. Serum NGF was significantly higher in GCA patients (n = 28) vs. controls (n = 48), whereas no significant difference was found for BDNF and NT-3. NGF and BDNF enhanced GCA-derived temporal artery VSMC proliferation and BDNF facilitated migration of temporal artery VSMCs in patients with GCA compared to controls.Conclusions
Our results suggest that NTs and NTRs are involved in vascular remodelling of GCA. In GCA-derived temporal artery VSMC, NGF promoted proliferation and BDNF enhanced migration by binding to TrkB and p75NTR receptors. Further experiments are needed on a larger number of VSMC samples to confirm these results.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0487-z) contains supplementary material, which is available to authorized users. 相似文献993.
994.
L. Krols Jean-Jacques Martin Gilles David Nicole Van Regemorter Ali Benomar A. Löfgren Giovanni Stevanin Alexandra Dürr Alexis Brice C. Van Broeckhoven 《Human genetics》1997,99(2):225-232
We have previously mapped the gene for autosomal dominant cerebellar ataxia type II (ADCAII) to chromosome 3p12-p21.1 in
a region of 33 cM by using four families of different geographic origin. In this study, we analysed the families with nine
additional simple tandem repeat markers located in the ADCAII candidate region. An extensive clinical evaluation was also
performed in the Belgian family CA-1 on two probably affected and seven at-risk individuals by means of ophthalmological examination
and magnetic resonance imaging. Based on informative recombinants, we were able to reduce the ADCAII candidate region to the
12-cM region between D3S1300 and D3S1285. Furthermore, haplotype analysis among the families suggested that the most likely
location of the ADCAII gene is within the 6.2-cM interval between D3S3698 and D3S1285. Because of the documented anticipation
in ADCAII families, we also analysed family CA-1 with six polymorphic triplet repeat markers located on chromosome 3. None
of these markers showed expanded alleles.
Received: 16 August 1996 / Revised: 7 October 1996 相似文献
995.
Nelson-Rees Walter A. Kniazeff Alexis J. Malley Roberta L. Darby Norman B. 《Chromosoma》1967,23(2):154-161
Somatic chromosomes of a female and male Himalayan thar, Hemitragus jemlahicus (H. Smith) are described. The diploid number is 48, there are 12 atelocentric and 34 telocentric autosomes in both sexes, the X-chromosome is meta- or submetacentric. The morphological appearance of the Y-chromosome is compared with that of other bovid species including recent observations on the goat Capra hircus.Supported by Contract No. PH 43-63-13 between the National Cancer Institute of the National Institutes of Health and the University of California. 相似文献
996.
Alexis Nazareno Campetelli Noelia Edith Monesterolo Gabriela Previtali Verónica Silvina Santander Marina Rafaela Amaiden Carlos Angel Arce Javier Valdez-Taubas César Horacio Casale 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Glucose induces H+-ATPase activation in Saccharomyces cerevisiae. Our previous study showed that (i) S. cerevisiae plasma membrane H+-ATPase forms a complex with acetylated tubulin (AcTub), resulting in inhibition of the enzyme activity; (ii) exogenous glucose addition results in the dissociation of the complex and recovery of the enzyme activity.Methods
We used classic biochemical and molecular biology tools in order to identify the key components in the mechanism that leads to H+-ATPase activation after glucose treatment.Results
We demonstrate that glucose-induced dissociation of the complex is due to pH-dependent activation of a protease that hydrolyzes membrane tubulin. Biochemical analysis identified a serine protease with a kDa of 35–40 and an isoelectric point between 8 and 9. Analysis of several knockout yeast strains led to the detection of Lpx1p as the serine protease responsible of tubulin proteolysis. When lpx1Δ cells were treated with glucose, tubulin was not degraded, the AcTub/H+-ATPase complex did not undergo dissociation, and H+-ATPase activation was significantly delayed.Conclusion
Our findings indicate that the mechanism of H+-ATPase activation by glucose involves a decrease in the cytosolic pH and consequent activation of a serine protease that hydrolyzes AcTub, accelerating the process of the AcTub/H+-ATPase complex dissociation and the activation of the enzyme.General significance
Our data sheds light into the mechanism by which acetylated tubulin dissociates from the yeast H+-ATPase, identifying a degradative step that remained unknown. This finding also proposes an indirect way to pharmacologically regulate yeast H+-ATPase activity and open the question about mechanistic similarities with other higher eukaryotes. 相似文献997.
Alexis Guerin-Laguette Nicholas Cummings Nina Hesom-Williams Ruth Butler Yun Wang 《Mycorrhiza》2013,23(2):87-98
This study compiles the results from an examination of mycorrhizae on root samples from Tuber melanosporum truffières in New Zealand. Samples were taken over 5 years from 328 trees in 43 truffières established with nursery-inoculated trees. Mycorrhizae were analysed using a combination of morphological and molecular techniques, focusing on the identification of Tuber species. Results show that 49% of the trees, and nearly 90% of the truffières, retained T. melanosporum mycorrhizae up to 21 years after planting. Tuber mycorrhizae with spiky cystidia were found on 26.9% of the tested trees: Tuber brumale (5.5%), Tuber maculatum (10.7%), and unidentified Tuber species (10.7%), and were detected in 67% of the truffières tested. T. brumale was found in 28% and T. maculatum in 35% of the truffières. In 56% of the truffières, T. melanosporum was found to occur with spiky Tuber species. The existence of T. brumale and T. maculatum in the same truffière was recorded only once. Forty-four percent of trees examined had Scleroderma-like (SCL) mycorrhizae and 50% of trees hosted other ectomycorrhizal species (OE). For all categories of mycorrhizal species examined, the variation between truffières was greater than variation within each truffière. Overall results indicate that Corylus avellana tends to be more receptive to mycorrhizae of Tuber species than Quercus robur but is not necessarily more productive. In productive truffières, Q. robur appears to host SCL mycorrhizae more often than C. avellana. This is the first study of its scale to analyse the mycorrhizal species associated with T. melanosporum truffières in the Southern Hemisphere. 相似文献
998.
Benoit Maillot Nicolas Lévy Sylvia Eiler Corinne Crucifix Florence Granger Ludovic Richert Pascal Didier Julien Godet Karine Pradeau-Aubreton Stéphane Emiliani Alexis Nazabal Paul Lesbats Vincent Parissi Yves Mely Dino Moras Patrick Schultz Marc Ruff 《PloS one》2013,8(4)
Integration of the HIV-1 cDNA into the human genome is catalyzed by the viral integrase (IN) protein. Several studies have shown the importance of cellular cofactors that interact with integrase and affect viral integration and infectivity. In this study, we produced a stable complex between HIV-1 integrase, viral U5 DNA, the cellular cofactor LEDGF/p75 and the integrase binding domain of INI1 (INI1-IBD), a subunit of the SWI/SNF chromatin remodeling factor. The stoichiometry of the IN/LEDGF/INI1-IBD/DNA complex components was found to be 4/2/2/2 by mass spectrometry and Fluorescence Correlation Spectroscopy. Functional assays showed that INI1-IBD inhibits the 3′ processing reaction but does not interfere with specific viral DNA binding. Integration assays demonstrate that INI1-IBD decreases the amount of integration events but inhibits by-product formation such as donor/donor or linear full site integration molecules. Cryo-electron microscopy locates INI1-IBD within the cellular DNA binding site of the IN/LEDGF complex, constraining the highly flexible integrase in a stable conformation. Taken together, our results suggest that INI1 could stabilize the PIC in the host cell, by maintaining integrase in a stable constrained conformation which prevents non-specific interactions and auto integration on the route to its integration site within nucleosomes, while LEDGF organizes and stabilizes an active integrase tetramer suitable for specific vDNA integration. Moreover, our results provide the basis for a novel type of integrase inhibitor (conformational inhibitor) representing a potential new strategy for use in human therapy. 相似文献
999.
Georgia A. F. Ladbury Magda Gavana Kostas Danis Anna Papa Dimitris Papamichail Spiros Mourelatos Sandra Gewehr George Theocharopoulos Stefanos Bonovas Alexis Benos Takis Panagiotopoulos 《PloS one》2013,8(11)
Introduction
During summer 2010, 262 human cases including 35 deaths from West Nile virus (WNV) infection were reported from Central Macedonia, Greece. Evidence from mosquitoes, birds and blood donors demonstrated that the epidemic was caused by WNV lineage 2, which until recently was considered of low virulence. We conducted a household seroprevalence study to estimate the spread of infection in the population during the epidemic, ascertain the relationship of infection to clinical disease, and identify risk factors for infection.Methods
We used a two-stage cluster design to select a random sample of residents aged ≥18 years in the outbreak epicentre. We collected demographic, medical, and risk factor data using standard questionnaires and environmental checklists, and tested serum samples for presence of WNV IgG and IgM antibodies using ELISA.Results
Overall, 723 individuals participated in the study, and 644 blood samples were available. Weighted seropositivity for IgG antibodies was 5.8% (95% CI: 3.8–8.6; n=41). We estimated that about 1 in 130 (1:141 to 1:124) infected individuals developed WNV neuroinvasive disease, and approximately 18% had clinical manifestations attributable to their infection. Risk factors for infection reflected high exposure to mosquitoes; rural residents were particularly at risk (prevalence ratio: 8.2, 95% CI: 1.1–58.7).Discussion
This study adds to the evidence that WNV lineage 2 strains can cause significant illness, demonstrating ratios of infection to clinical disease similar to those found previously for WNV lineage 1. 相似文献1000.
Elsa Kermorvant-Duchemin Alexis Christophe Pinel Sophie Lavalette Delphine Lenne William Raoul Bertrand Calippe Francine Behar-Cohen José-Alain Sahel Xavier Guillonneau Florian Sennlaub 《PloS one》2013,8(11)
Recent evidence suggests that transient hyperglycemia in extremely low birth weight infants is strongly associated with the occurrence of retinopathy of prematurity (ROP). We propose a new model of Neonatal Hyperglycemia-induced Retinopathy (NHIR) that mimics many aspects of retinopathy of prematurity. Hyperglycemia was induced in newborn rat pups by injection of streptozocine (STZ) at post natal day one (P1). At various time points, animals were assessed for vascular abnormalities, neuronal cell death and accumulation and activation of microglial cells. We here report that streptozotocin induced a rapid and sustained increase of glycemia from P2/3 to P6 without affecting rat pups gain weight or necessitating insulin treatment. Retinal vascular area was significantly reduced in P6 hyperglycemic animals compared to control animals. Hyperglycemia was associated with (i) CCL2 chemokine induction at P6, (ii) a significant recruitment of inflammatory macrophages and an increase in total number of Iba+ macrophages/microglia cells in the inner nuclear layer (INL), and (iii) excessive apoptosis in the INL. NHIR thereby reproduces several aspects of ischemic retinopathies, including ROP and diabetic retinopathies, and might be a useful model to decipher hyperglycemia-induced cellular and molecular mechanisms in the small rodent. 相似文献