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51.
Mercedes F. Rivera Ju-Youn Lee Monika Aneja Vishalkant Goswami Liying Liu Irina M. Velsko Sasanka S. Chukkapalli Indraneel Bhattacharyya Hao Chen Alexandra R. Lucas Lakshmyya N. Kesavalu 《PloS one》2013,8(2)
Periodontal disease (PD) and atherosclerosis are both polymicrobial and multifactorial and although observational studies supported the association, the causative relationship between these two diseases is not yet established. Polymicrobial infection-induced periodontal disease is postulated to accelerate atherosclerotic plaque growth by enhancing atherosclerotic risk factors of orally infected Apolipoprotein E deficient (ApoEnull) mice. At 16 weeks of infection, samples of blood, mandible, maxilla, aorta, heart, spleen, and liver were collected, analyzed for bacterial genomic DNA, immune response, inflammation, alveolar bone loss, serum inflammatory marker, atherosclerosis risk factors, and aortic atherosclerosis. PCR analysis of polymicrobial-infected (Porphyromonas gingivalis [P. gingivalis], Treponema denticola [T. denticola], and Tannerella forsythia [T. forsythia]) mice resulted in detection of bacterial genomic DNA in oral plaque samples indicating colonization of the oral cavity by all three species. Fluorescent in situ hybridization detected P. gingivalis and T. denticola within gingival tissues of infected mice and morphometric analysis showed an increase in palatal alveolar bone loss (p<0.0001) and intrabony defects suggesting development of periodontal disease in this model. Polymicrobial-infected mice also showed an increase in aortic plaque area (p<0.05) with macrophage accumulation, enhanced serum amyloid A, and increased serum cholesterol and triglycerides. A systemic infection was indicated by the detection of bacterial genomic DNA in the aorta and liver of infected mice and elevated levels of bacterial specific IgG antibodies (p<0.0001). This study was a unique effort to understand the effects of a polymicrobial infection with P. gingivalis, T. denticola and T. forsythia on periodontal disease and associated atherosclerosis in ApoEnull mice. 相似文献
52.
Ilja I. Brusentsov Alexey V. Katokhin Irina V. Brusentsova Sergei V. Shekhovtsov Sergei N. Borovikov Grigoriy G. Goncharenko Lyudmila A. Lider Boris V. Romashov Olga T. Rusinek Samat K. Shibitov Marat M. Suleymanov Andrey V. Yevtushenko Viatcheslav A. Mordvinov 《PloS one》2013,8(4)
Opisthorchis felineus or Siberian liver fluke is a trematode parasite (Opisthorchiidae) that infects the hepato-biliary system of humans and other mammals. Despite its public health significance, this wide-spread Eurasian species is one of the most poorly studied human liver flukes and nothing is known about its population genetic structure and demographic history. In this paper, we attempt to fill this gap for the first time and to explore the genetic diversity in O. felineus populations from Eastern Europe (Ukraine, European part of Russia), Northern Asia (Siberia) and Central Asia (Northern Kazakhstan). Analysis of marker DNA fragments from O. felineus mitochondrial cytochrome c oxidase subunit 1 and 3 (cox1, cox3) and nuclear rDNA internal transcribed spacer 1 (ITS1) sequences revealed that genetic diversity is very low across the large geographic range of this species. Microevolutionary processes in populations of trematodes may well be influenced by their peculiar biology. Nevertheless, we suggest that lack of population genetics structure observed in O. felineus can be primarily explained by the Pleistocene glacial events and subsequent sudden population growth from a very limited group of founders. Rapid range expansion of O. felineus through Asian and European territories after severe bottleneck points to a high dispersal potential of this trematode species. 相似文献
53.
Zohreh Varasteh Ola ?berg Irina Velikyan Gunnar Lindeberg Jens S?rensen Mats Larhed Gunnar Antoni Mattias Sandstr?m Vladimir Tolmachev Anna Orlova 《PloS one》2013,8(12)
Expression of the gastrin-releasing peptide receptor (GRPR) in prostate cancer suggests that this receptor can be used as a potential molecular target to visualize and treat these tumors. We have previously investigated an antagonist analog of bombesin (D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2, RM26) conjugated to 1,4,7-triazacyclononane-N,N'',N''''-triacetic acid (NOTA) via a diethylene glycol (PEG2) spacer (NOTA-P2-RM26) labeled with 68Ga and 111In. We found that this conjugate has favorable properties for in vivo imaging of GRPR-expression. The focus of this study was to develop a 18F-labelled PET agent to visualize GRPR. NOTA-P2-RM26 was labeled with 18F using aluminum-fluoride chelation. Stability, in vitro binding specificity and cellular processing tests were performed. The inhibition efficiency (IC50) of the [natF]AlF-NOTA-P2-RM26 was compared to that of the natGa-loaded peptide using 125I-Tyr4-BBN as the displacement radioligand. The pharmacokinetics and in vivo binding specificity of the compound were studied. NOTA-P2-RM26 was labeled with 18F within 1 h (60-65% decay corrected radiochemical yield, 55 GBq/µmol). The radiopeptide was stable in murine serum and showed high specific binding to PC-3 cells. [natF]AlF-NOTA-P2-RM26 showed a low nanomolar inhibition efficiency (IC50=4.4±0.8 nM). The internalization rate of the tracer was low. Less than 14% of the cell-bound radioactivity was internalized after 4 h. The biodistribution of [18F]AlF-NOTA-P2-RM26 demonstrated rapid blood clearance, low liver uptake and low kidney retention. The tumor uptake at 3 h p.i. was 5.5±0.7 %ID/g, and the tumor-to-blood, -muscle and -bone ratios were 87±42, 159±47, 38±16, respectively. The uptake in tumors, pancreas and other GRPR-expressing organs was significantly reduced when excess amount of non-labeled peptide was co-injected. The low uptake in bone suggests a high in vivo stability of the Al-F bond. High contrast PET image was obtained 3 h p.i. The initial biological results suggest that [18F]AlF-NOTA-P2-RM26 is a promising candidate for PET imaging of GRPR in vivo. 相似文献
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56.
AbstractIn northern Belarus, we have documented a decline in the local stoat Mustela erminea population following the naturalisation of the American mink Mustela vison. The most likely cause is the reduction in the density and distribution of the main prey of stoats, the riparian voles (the water vole Arvicola terrestris and the root vole Microtus oeconomus), due to excessive predation by mink. Since the stoat population has declined, the number of weasels Mustela nivalis in marshlands has increased and their mean body mass has increased, correlated with the higher number and mean weights of rodents available for weasels in marshland compared with forest habitats. 相似文献
57.
Sushil Kumar Tomar Stefan H. Knauer Monali NandyMazumdar Paul R?sch Irina Artsimovitch 《Nucleic acids research》2013,41(22):10077-10085
Escherichia coli RfaH activates gene expression by tethering the elongating RNA polymerase to the ribosome. This bridging action requires a complete refolding of the RfaH C-terminal domain (CTD) from an α-helical hairpin, which binds to the N-terminal domain (NTD) in the free protein, to a β-barrel, which interacts with the ribosomal protein S10 following RfaH recruitment to its target operons. The CTD forms a β-barrel when expressed alone or proteolytically separated from the NTD, indicating that the α-helical state is trapped by the NTD, perhaps co-translationally. Alternatively, the interdomain contacts may be sufficient to drive the formation of the α-helical form. Here, we use functional and NMR analyses to show that the denatured RfaH refolds into the native state and that RfaH in which the order of the domains is reversed is fully functional in vitro and in vivo. Our results indicate that all information necessary to determine its fold is encoded within RfaH itself, whereas accessory factors or sequential folding of NTD and CTD during translation are dispensable. These findings suggest that universally conserved RfaH homologs may change folds to accommodate diverse interaction partners and that context-dependent protein refolding may be widespread in nature. 相似文献
58.
Irina A. Beschetnova Dmitry N. Kaluzhny Mikhail A. Livshits Anna K. Shchyolkina Olga F. Borisova 《Journal of biomolecular structure & dynamics》2013,31(6):789-799
Abstract Oligonucleotides 3′-d(GT)5-(CH2CH2O)3-d(GT)5-3′ (parGT), containing GT repeats present in the telomeric DNA from Saccharomyces cerevisiae, had been demonstrated to form bimolecular structure, GT-quadruplex (qGT) [O. F. Borisova et al. FEBS Letters 306, 140–142 (1992)]. Four d(GT)5 strands of the GT-quadruplex are parallel and form five G-quartets while thymines are bulged out. The four GT repeats when flanked by guanines, 3′-dG(TG)4G-(CH2CH2O)3- dG(GT)4G-3′ (hp-GT), had been shown to form a novel parallel-stranded (ps) double helix with G·G and T·T base pairs (hp-GT ps-DNA) [A. K. Shchyolkina et al. J. Biomol. Struct. Dynam. 18, 493–503 (2001)]. In the present study the intercalator ethidium bromide (Et) was used for probing the two structures. The mode of Et binding and its effect on thermostability of qGT and hp-GT were compared. The quantum yield (q) and the fluorescence lifetime (τ) of Et:qGT (q = 0.15 ±0.01 and τ = 24 ±1 ns) and Et:hp-GT (q = 0.10 ± 0.01 and τ = 16.5 ± 1 ns) indicative of intercalation mode of Et binding were determined. Et binding to qGT was found to be cooperative with corresponding coefficient ω = 3.9 ± 0.1 and the binding constant K= (6.4 ± 0.1)·10M?1. The maximum number of Et molecules intercalating into GT-quadruplex is as high as twice the number of inerspaces between G-quartets (eight in our case). The data conform to the model of Et association with GT-quadruplex suggested earlier [O. F. Borisova et al. Mol. Biol. (Russ) 35, 732–739 (2001)]. The anticooperative type of Et binding was observed in case of hp- GT ps-DNA, with the maximum number of bound Et molecules, N = 4 ÷ 5, and the association constant K = (1.5 ± 0.1)·105 M?1. Thermodynamic parameters of formation of Et:qGT and EtBr:hp-GT complexes were calculated from UV thermal denaturation profiles. 相似文献
59.
Natalya Semenova Irina Madaeva Tatyana Bairova Sergey Kolesnikov Lubov Kolesnikova 《Chronobiology international》2013,30(10):1399-1408
ABSTRACTA comparative analysis of lipid peroxidation processes and antioxidant defense system in Caucasian menopausal women with/without insomnia depending on the genotype of Clock 3111T/C gene polymorphism was performed. Two hundred and fourteen Caucasian menopausal women divided into control (without insomnia) and main group (with insomnia) were examined. Lipid peroxidation (conjugated dienes, thiobarbituric acid reactants) and antioxidant defense system parameters (?-tocopherol, retinol, reduced and oxidized glutathione, glutathione S-transferase, glutathione peroxidase, glutathione reductase, superoxide dismutase) were determined by spectrofluorophotometer and immunoenzymometric methods. Patients with insomnia carriers of the TT-genotype had a significantly higher thiobarbituric acid reactants level and glutathione peroxidase activity as compared to group with insomnia carriers of the minor 3111C-allele (p < .05). A comparative analysis of the parameters in the women of the main and control groups showed higher conjugated dienes, thiobarbituric acid reactants levels and lower retinol, reduced glutathione levels, glutathione reductase activity in women with insomnia carriers of the TT-genotype (p < .05). The carriers of the minor allele with insomnia had a higher conjugated dienes levels and lower glutathione peroxidase activity as compared to control (p < .05). Thus, lipid peroxidation and antioxidant system parameters in Caucasian menopausal women with insomnia depend on the Clock 3111T/C gene polymorphism. 相似文献
60.
Protein changes and proteolytic degradation in red and white clover plants subjected to waterlogging
Veselin Stoychev Lyudmila Simova-Stoilova Irina Vaseva Anelia Kostadinova Rosa Nenkova Urs Feller K. Demirevska 《Acta Physiologiae Plantarum》2013,35(6):1925-1932
Red (Trifolium pratense L., cv. “Start”) and white clover varieties (Trifolium repens L., cv. “Debut” and cv. “Haifa”) were waterlogged for 14 days and subsequently recovered for the period of 21 days. Physiological and biochemical responses of the clover varieties were distinctive, which suggested different sensitivity toward flooding. The comparative study of morphological and biochemical parameters such as stem length, leaflet area, dry weight, protein content, protein pattern and proteolytic degradation revealed prominent changes under waterlogging conditions. Protease activity in the stressed plants increased significantly, especially in red clover cv. “Start”, which exhibited eightfold higher azocaseinolytic activity compared to the control. Changes in the protein profiles were detected by SDS-PAGE electrophoresis. The specific response of some proteins (Rubisco, Rubisco-binding protein, Rubisco activase, ClpA and ClpP protease subunits) toward the applied stress was assessed by immunoblotting. The results characterized the red clover cultivar “Start” as the most sensitive toward waterlogging, expressing reduced levels of Rubisco large and small subunits, high content of ClpP protease subunits and increased activity of protease isoforms. 相似文献