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151.
152.
Omar Riah Philippe Courrière Jean-Claude Dousset Nathalie Todeschi Christian Labat 《Cellular and molecular neurobiology》1998,18(3):311-318
1. Nicotine and its main metabolite, cotinine, were reported to have distinct behavioral activities in mammals.2. In this study, cotinine was synthesized without detectable nicotine contamination to compare the ability of nicotine and cotinine to pass the blood–brain barrier (BBB)in rats.3. The alkaloids were extracted from plasma and brain tissues by methanol, identified by thin-layer chromatography, and quantified by high-pressure liquid chromatography and radioimmunoassays.4. Consistently, the three methods showed that the passage of cotinine was time, route of administration, and dose dependent and that nicotine was more efficient than cotinine to pass the BBB.5. The results suggest that these alkaloids may have central activities that probably result from their actions at distinct molecular levels. 相似文献
153.
Jean-Claude Chalchat Raymond-Philippe Garry André Michet Alain Remery 《Phytochemistry》1985,24(10):2443-2444
The essential oils of Pinus sylvestris from French Massif Central are described. Forty-six compounds have been identified by spectral methods. Two chemotypes are recognized. 相似文献
154.
Hussein Akil Amazigh Abbaci Fabrice Lalloué Barbara Bessette Léa M. M. Costes Linda Domballe Sandrine Charreau Karline Guilloteau Lucie Karayan-Tapon Fran?ois-Xavier Bernard Franck Morel Marie-Odile Jauberteau Jean-Claude Lecron 《PloS one》2015,10(3)
Interleukin-22 (IL-22) is a member of the IL-10 cytokine family that binds to a heterodimeric receptor consisting of IL-22 receptor 1 (IL-22R1) and IL-10R2. IL-22R expression was initially characterized on epithelial cells, and plays an essential role in a number of inflammatory diseases. Recently, a functional receptor was detected on cancer cells such as hepatocarcinoma and lung carcinoma, but its presence was not reported in glioblastoma (GBM). Two GBM cell lines and 10 primary cell lines established from patients undergoing surgery for malignant GBM were used to investigate the expression of IL-22 and IL-22R by using quantitative RT-PCR, western blotting and confocal microscopy studies. The role of IL-22 in proliferation and survival of GBM cell lines was investigated in vitro by BrdU and ELISA cell death assays. We report herein that the two subunits of the IL-22R complex are expressed on human GBM cells. Their activation, depending on exogenous IL-22, induced antiapoptotic effect and cell proliferation. IL-22 treatment of GBM cells resulted in increased levels of phosphorylated Akt, STAT3 signaling protein and its downstream antiapoptotic protein Bcl-xL and decreased level of phosphorylated ERK1/2. In addition, IL-22R subunits were expressed in all the 10 tested primary cell lines established from GBM tumors. Our results showed that IL-22R is expressed on GBM established and primary cell lines. Depending on STAT3, ERK1/2 and PI3K/Akt pathways, IL-22 induced GBM cell survival. These data are consistent with a potential role of IL-22R in tumorigenesis of GBM. Since endogenous IL-22 was not detected in all studied GBM cells, we hypothesize that IL-22R could be activated by immune microenvironmental IL-22 producing cells. 相似文献
155.
Alexandra Mangili Julian Falutz Jean-Claude Mamputu Miganush Stepanians Brooke Hayward 《PloS one》2015,10(10)
BackgroundTesamorelin, a synthetic analog of human growth hormone-releasing factor, decreases visceral adipose tissue (VAT) in human immunodeficiency virus (HIV)-infected patients with lipodystrophy.Objectives1) To evaluate the utility of patient characteristics and validated disease-risk scores, namely indicator variables for the metabolic syndrome defined by the International Diabetes Federation (MetS-IDF) or the National Cholesterol Education Program (MetS-NCEP) and the Framingham Risk Score (FRS), as predictors of VAT reduction during tesamorelin therapy at 3 and 6 months, and 2) To explore the characteristics of patients who reached a threshold of VAT <140 cm2, a level associated with lower risk of adverse health outcomes, after 6 months of treatment with tesamorelin.MethodsData were analyzed from two Phase 3 studies in which HIV-infected patients with excess abdominal fat were randomized in a 2:1 ratio to receive tesamorelin 2 mg (n = 543) or placebo (n = 263) subcutaneously daily for 6 months, using ANOVA and ANCOVA models.ResultsMetabolic syndrome (MetS-IDF or MetS-NCEP) and FRS were significantly associated with VAT at baseline. Presence of metabolic syndrome ([MetS-NCEP), triglyceride levels >1.7 mmol/L, and white race had a significant impact on likelihood of response to tesamorelin after 6 months of therapy (interaction p-values 0.054, 0.063, and 0.025, respectively). No predictive factors were identified at 3 months. The odds of a VAT reduction to <140 cm2 for subjects treated with tesamorelin was 3.9 times greater than that of subjects randomized to placebo after controlling for study, gender, baseline body mass index (BMI) and baseline VAT (95% confidence interval [CI] 2.03; 7.44).ConclusionsIndividuals with baseline MetS-NCEP, elevated triglyceride levels, or white race were most likely to experience reductions in VAT after 6 months of tesamorelin treatment. The odds of response of VAT <140 cm2 was 3.9 times greater for tesamorelin-treated patients than that of patients receiving placebo. 相似文献
156.
Blanda Di Luccia Raffaella Crescenzo Arianna Mazzoli Luisa Cigliano Paola Venditti Jean-Claude Walser Alex Widmer Loredana Baccigalupi Ezio Ricca Susanna Iossa 《PloS one》2015,10(8)
A fructose-rich diet can induce metabolic syndrome, a combination of health disorders that increases the risk of diabetes and cardiovascular diseases. Diet is also known to alter the microbial composition of the gut, although it is not clear whether such alteration contributes to the development of metabolic syndrome. The aim of this work was to assess the possible link between the gut microbiota and the development of diet-induced metabolic syndrome in a rat model of obesity. Rats were fed either a standard or high-fructose diet. Groups of fructose-fed rats were treated with either antibiotics or faecal samples from control rats by oral gavage. Body composition, plasma metabolic parameters and markers of tissue oxidative stress were measured in all groups. A 16S DNA-sequencing approach was used to evaluate the bacterial composition of the gut of animals under different diets. The fructose-rich diet induced markers of metabolic syndrome, inflammation and oxidative stress, that were all significantly reduced when the animals were treated with antibiotic or faecal samples. The number of members of two bacterial genera, Coprococcus and Ruminococcus, was increased by the fructose-rich diet and reduced by both antibiotic and faecal treatments, pointing to a correlation between their abundance and the development of the metabolic syndrome. Our data indicate that in rats fed a fructose-rich diet the development of metabolic syndrome is directly correlated with variations of the gut content of specific bacterial taxa. 相似文献
157.
Isabelle Perrault Fadi?F. Hamdan Marlène Rio José-Mario Capo-Chichi Nathalie Boddaert Jean-Claude Décarie Bruno Maranda Rima Nabbout Michel Sylvain Anne Lortie Philippe?P. Roux Elsa Rossignol Xavier Gérard Giulia Barcia Patrick Berquin Arnold Munnich Guy?A. Rouleau Josseline Kaplan Jean-Michel Rozet Jacques?L. Michaud 《American journal of human genetics》2014,94(6):891-897
Epileptic encephalopathies are increasingly thought to be of genetic origin, although the exact etiology remains uncertain in many cases. We describe here three girls from two nonconsanguineous families affected by a clinical entity characterized by dysmorphic features, early-onset intractable epilepsy, intellectual disability, and cortical blindness. In individuals from each family, brain imaging also showed specific changes, including an abnormally marked pontobulbar sulcus and abnormal signals (T2 hyperintensities) and atrophy in the occipital lobe. Exome sequencing performed in the first family did not reveal any gene with rare homozygous variants shared by both affected siblings. It did, however, show one gene, DOCK7, with two rare heterozygous variants (c.2510delA [p.Asp837Alafs∗48] and c.3709C>T [p.Arg1237∗]) found in both affected sisters. Exome sequencing performed in the proband of the second family also showed the presence of two rare heterozygous variants (c.983C>G [p.Ser328∗] and c.6232G>T [p.Glu2078∗]) in DOCK7. Sanger sequencing confirmed that all three individuals are compound heterozygotes for these truncating mutations in DOCK7. These mutations have not been observed in public SNP databases and are predicted to abolish domains critical for DOCK7 function. DOCK7 codes for a Rac guanine nucleotide exchange factor that has been implicated in the genesis and polarization of newborn pyramidal neurons and in the morphological differentiation of GABAergic interneurons in the developing cortex. All together, these observations suggest that loss of DOCK7 function causes a syndromic form of epileptic encephalopathy by affecting multiple neuronal processes. 相似文献
158.
Zonula Occludens (ZO) proteins are ubiquitous scaffolding proteins providing the structural basis for the assembly of multiprotein complexes at the cytoplasmic surface of the plasma membrane and linking transmembrane proteins to the filamentous cytoskeleton. They belong to the large family of membrane-associated guanylate kinase (MAGUK)-like proteins comprising a number of subfamilies based on domain content and sequence similarity. ZO proteins were originally described to localize specifically to tight junctions, or Zonulae Occludentes, but this notion was rapidly reconsidered since ZO proteins were found to associate with adherens junctions as well as with gap junctions, particularly with connexin-made intercellular channels, and also with a few other membrane channels. Accumulating evidence reveals that in addition to having passive scaffolding functions in organizing gap junction complexes, including connexins and cytoskeletals, ZO proteins (particularly ZO-1) also actively take part in the dynamic function as well as in the remodeling of junctional complexes in a number of cellular systems. This article is part of a Special Issue entitled: Reciprocal influences between cell cytoskeleton and membrane channels, receptors and transporters. Guest Editor: Jean Claude Hervé. 相似文献
159.
Chizuru Akatsu Duriya Fongmoon Shuji Mizumoto Jean-Claude Jacquinet Prachya Kongtawelert Shuhei Yamada Kazuyuki Sugahara 《Glycoconjugate journal》2010,27(4):387-399
Glycosaminoglycans (GAGs) like chondroitin sulfate (CS) and heparan sulfate (HS) are synthesized on the tetrasaccharide linkage
region, GlcAβ1-3Galβ1-3Galβ1-4Xylβ1-O-Ser, of proteoglycans. The Xyl can be modified by 2-O-phosphate in both CS and HS, whereas the Gal residues can be sulfated at C-4 and/or C-6 in CS but not in HS. To study the
roles of these modifications, monoclonal antibodies were developed against linkage glycopeptides of shark cartilage CS proteoglycans,
and one was characterized in detail. This antibody bound hexa- and pentasaccharide-peptides more strongly than unsaturated
tetrasaccharide-peptides with the unnatural fourth sugar residue (unsaturated hexuronic acid), suggesting the importance of
the fifth and/or fourth saccharide residue GalNAc-5 and/or GlcA-4. Its reactivity was not affected by treatment with chondro-4-sulfatase
or alkaline phosphatase, suggesting that 4-O-sulfate on the Gal residues and 2-O-phosphate on the Xyl residue were not recognized. Treatment with weak alkali to cleave the Xyl-Ser linkage completely abolished
the binding activity, suggesting the importance of the peptide moiety of the hexasaccharide-peptide for the binding. Based
on the amino acid composition and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analyses, it
was revealed that the peptide moiety is composed of four amino acids, Ser, Pro, Gly, and Glu. Furthermore, the antibody stained
wild-type CHO cells significantly, but much weakly mutant cells deficient in xylosyl- or galactosyltransferase-I required
for the biosynthesis of the linkage region. These results suggest that the antibody recognizes the structure GalNAc(±6-O-sulfate)-GlcA-Gal-Gal-Xyl-Ser-(Pro, Gly, Glu). The antibody will be a useful tool for investigating the significance of the
linkage region in the biosynthesis and/or intracellular transport of different GAG chains especially since such tools to study
the linkage region are lacking. 相似文献
160.
Jean-Claude Rouby 《Biologicals》2010,38(3):354-357
There are different ways to define the concept of ‘low levels’ of extraneous agents in vaccines and vaccine starting materials, based on the amount of extraneous agents as such, the sensitivity of the detection method and the probability approach linked to the sampling method. None of these approaches, however, is entirely satisfactory – a general definition of a ‘low level’ cannot be provided. Since the main point is the safety of medicinal products, the risk analysis approach to ‘low level’ contaminations can be considered as a way to overcome the abovementioned deadlock. But as too many variables impact the risk analysis, it cannot be properly performed either. In practice, seeds are tested to show freedom from extraneous agents, the other raw materials are inactivated through a validated method. However, there are technical and regulatory limits in both cases, and neither testing nor inactivation entirely guarantees freedom from extraneous agents. Despite this unsatisfactory situation, it should be acknowledged that no truly significant disease outbreak linked to an extraneous agent has been identified until today. Regulatory actions are mainly undertaken when a sanitary problem occurs. In the end, companies remain responsible for their products. 相似文献