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21.
Suxia Li Bin Li Haoran Jiang Yao Wang Mingli Qu Haoyun Duan Qingjun Zhou Weiyun Shi 《PloS one》2013,8(4)
Purpose
Macrophages have been shown to play a critical role in the wound healing process. In the present study, the role of macrophages in wound healing after autologous corneal transplantation was investigated by depleting local infiltrated macrophages.Methods
Autologous corneal transplantation model was used to induce wound repair in Balb/c mice. Macrophages were depleted by sub-conjunctival injections of clodronate-containing liposomes (Cl2MDP-LIP). The presence of CD11b+ F4/80+ macrophages, α-smooth muscle actin+ (α-SMA+) myofibroblasts, CD31+ vascular endothelial cells and NG2 + pericytes was examined by immunohistochemical and corneal whole-mount staining 14 days after penetrating keratoplasty. Peritoneal macrophages were isolated from Balb/c mice and transfused into conjunctiva to examine the recovery role of macrophages depletion on wound healing after autologous corneal transplantation.Results
Sub-conjunctival Cl2MDP-LIP injection significantly depleted the corneal resident phagocytes and infiltrated macrophages into corneal stroma. Compared with the mice injected with PBS-liposome, the Cl2MDP-LIP-injected mice showed few inflammatory cells, irregularly distributed extracellular matrix, ingrowth of corneal epithelium into stroma, and even the detachment of donor cornea from recipient. Moreover, the number of macrophages, myofibroblasts, endothelial cells and pericytes was also decreased in the junction area between the donor and recipient cornea in macrophage-depleted mice. Peritoneal macrophages transfusion recovered the defect of corneal wound healing caused by macrophages depletion.Conclusions
Macrophage depletion significantly impairs wound healing after autologous corneal transplantation through at least partially impacting on angiogenesis and wound closure. 相似文献22.
23.
Two star‐shaped tetranuclear Ru(II) complexes containing uncoordinated imidazole groups: synthesis,characterization, photophysical and pH sensing properties
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Tetrapodal ligands H4L1 and H4L2 containing imidazole groups have been synthesized by the reaction of 1,10‐phenanthroline‐5,6‐dione with 1,2,4,5‐tetrakis[(4‐formylphenoxy)methyl]benzene and 1,2,4,5‐tetrakis[(3‐formylphenoxy)methyl]benzene, respectively, in presence of NH4OAc. Two star‐shaped complexes [{Ru(bpy)2}4(μ4‐H4L1)](PF6)8 and [{Ru(bpy)2}4(μ4‐H4L2)](PF6)8 (bpy = 2,2′‐bipyridine) have been prepared by refluxing Ru(bpy)2Cl2·2H2O and each ligand in ethylene glycol. The deprotonated complexes [{Ru(bpy)2}4(μ4‐L1)](PF6)4 and [{Ru(bpy)2}4(μ4‐L2)](PF6)4 have been obtained by the reaction of sodium methoxide with [{Ru(bpy)2}4(μ4‐H4L1)](PF6)8 and [{Ru(bpy)2}4(μ4‐H4L2)](PF6)8, respectively, in methanol. The pH effects on the UV–vis light absorption and emission spectra of both complexes have been studied, and ground‐ and excited‐state ionization constants of both complexes have been derived. The photophysical properties of both complexes are strongly dependent on the solution pH. They act as proton‐induced off–on–off luminescent sensors through two successive deprotonation processes of imidazole groups, with a maximum on–off ratio of 8 in buffer solution at room temperature. Theoretical calculations for the highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LOMO) orbitals of bridging ligand are also presented for plausible explanations of the fluorescence changes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
24.
WEICHAO Zhai DERRICK YONG JEHAN JOMAA EL-JAWHARI RICHARD CUTHBERT DENNIS MCGONAGLE MAY WIN NAING ELENA JONES 《Cytotherapy》2019,21(8):803-819
Regardless of their tissue of origin, multipotent mesenchymal stromal cells (MSCs) are commonly expanded in vitro for several population doublings to achieve a sufficient number of cells for therapy. Prolonged MSC expansion has been shown to result in phenotypical, morphological and gene expression changes in MSCs, which ultimately lead to the state of senescence. The presence of senescent cells in therapeutic MSC batches is undesirable because it reduces their viability, differentiation potential and trophic capabilities. Additionally, senescent cells acquire senescence-activated secretory phenotype, which may not only induce apoptosis in the neighboring host cells following MSC transplantation, but also trigger local inflammatory reactions. This review outlines the current and promising new methodologies for the identification of senescent cells in MSC cultures, with a particular emphasis on non-destructive and label-free methodologies. Technologies allowing identification of individual senescent cells, based on new surface markers, offer potential advantage for targeted senescent cell removal using new-generation senolytic agents, and subsequent production of therapeutic MSC batches fully devoid of senescent cells. Methods or a combination of methods that are non-destructive and label-free, for example, involving cell size and spectroscopic measurements, could be the best way forward because they do not modify the cells of interest, thus maximizing the final output of therapeutic-grade MSC cultures. The further incorporation of machine learning methods has also recently shown promise in facilitating, automating and enhancing the analysis of these measured data. 相似文献
25.
利用75%乙醇对向日葵根化学成分进行提取;再用萃取法将向日葵根化学成分乙醇提取物分为石油醚萃取物浸膏、乙酸乙酯萃取物漫膏、正丁醇萃取物浸膏;最后用常压硅胶色谱从石油醚萃取物漫膏中分离得到1个甾体类化合物A,经质谱、碳核磁共振和氢核磁共振谱鉴定,确定出其结构为β-谷甾醇。 相似文献
26.
Qian Wei Lin Zhao Longyang Jiang Jia Bi Zhaojin Yu Lan Zhao Xinyue Song Mingli Sun Yuzong Chen Minjie Wei 《Journal of cellular physiology》2019,234(7):11888-11899
MiR-137 has been identified as potential hepatocellular carcinoma (HCC) prognostic biomarkers. Highly relevant HCC prognostic biomarkers may be derived from combinations of miR-137 with its target genes involved in the regulation of liver microenvironment. This study aimed at the discovery of such a combination with improved HCC prognosis performance than miR-137 or its target gene alone in a significantly higher number of HCC patients than previous studies. Analysis of the differentially expressed micro RNAs (miRNAs) between cancer and noncancer tissues reconfirmed miR-137 to be among the most relevant prognostic miRNAs and the data of 375 HCC patients and 50 normal cases were from the Cancer Genome Atlas (TCGA) data sets. Target genes were identified by the established search methods and Kaplan–Meier survival analysis of HCC patients was used to evaluate the overall survival (OS) and recurrence-free survival (RFS). Cox proportional hazards regression indicated that the miR-137 and its target gene AFM combination is an independent prognostic factor for the OS and RFS in HCC. In vitro experiments validated that miR-137 could bind to 3′-untranslated region of the AFM and promote the invasion and metastasis of HCC cell lines. The expressions of miR-137 and its liver microenvironment regulatory target gene AFM in combination significantly correlated with HCC progression in a higher number of patients than in previous studies, which suggested their potential as prognostic biomarkers for HCC. 相似文献
27.
Prisco M Santini F Baffa R Liu M Drakas R Wu A Baserga R 《The Journal of biological chemistry》2002,277(35):32078-32085
32D cells are a murine hemopoietic cell line that undergoes apoptosis upon withdrawal of interleukin-3 (IL-3) from the medium. 32D cells have low levels of the type 1 insulin-like growth factor (IGF-I) receptor and do not express insulin receptor substrate-1 (IRS-1) or IRS-2. Ectopic expression of IRS-1 delays apoptosis but cannot rescue 32D cells from IL-3 dependence. In 32D/IRS-1 cells, IRS-1 is detectable, as expected, in the cytosol/membrane compartment. The SV40 large T antigen is a nuclear protein that, by itself, also fails to protect 32D cells from apoptosis. Co-expression of IRS-1 with the SV40 T antigen in 32D cells results in nuclear translocation of IRS-1 and survival after IL-3 withdrawal. Expression of a human IGF-I receptor in 32D/IRS-1 cells also results in nuclear translocation of IRS-1 and IL-3 independence. The phosphotyrosine-binding domain, but not the pleckstrin domain, is necessary for IRS-1 nuclear translocation. Nuclear translocation of IRS-1 was confirmed in mouse embryo fibroblasts. These results suggest possible new roles for nuclear IRS-1 in IGF-I-mediated growth and anti-apoptotic signaling. 相似文献
28.
YONG M.; GUTIERREZ A.; PERERA G.; DURAND P.; POINTIER J.P. 《Journal of Molluscan Studies》2001,67(1):103-112
Conchological, anatomical and genetic characteristics werecompared
among several populations of the Biomphalaria havanensis
complexfrom Cuba and other localities in the Caribbean region. Two
morphometricmeasures (height and diameter) distinguished two closely
similarmorphs of the shell. The reproductive system also separated
thesemorphs, particularly upon comparison of sizes of the penis
sheathand the preputium. The two morphological groups differed in9
to 12 fixed alleles according to population. Further allozymicdata
analyzed in the present work confirmed this difference.The results
strongly support the assumption that the B. havanensis
complexincludes two distinct species: B. havanensis, for
which thetype locality is the swampy area near the vicinity of
Havana,Cuba and Biomphalaria sp. a species which commonly
occurs inCuba and in Dominican Republic. The taxonomic identity of
Biomphalariasp. is discussed. (Received 28 January 2000; accepted 15 August 2000) 相似文献
29.
Mingli Yan Xianjun Liu Chunyun Guan Lili Liu Jianhua Xiang Ying Lu Zhongsong Liu 《Genetica》2014,142(2):169-176
Arabidopsis Transparent Testa Glabra 1 (TTG1) genes were cloned from three diploid Brassica species (B. rapa, B. nigra and B. oleracea) and two amphidiploids species (B. juncea and B. carinata) by homology cloning. TTG1 homologues identified in all the accessions of the investigated species had a coding sequence of 1,014 bp. One copy was obtained from each diploid species and two copies from each amphidiploid species. Combined analysis of the TTG1 sequences cloned in this study with those obtained from public databases demonstrated that three, forty-five and seven nucleotides were specific variations in TTG1 genes from genomes A, B and C, respectively. Primers designed with genome-specific nucleotide variations were able to distinguish among TTG1 genes originating from genomes A, B and C in Brassica. Therefore, the TTG1 gene could serve as a candidate marker gene to detect the pollen flow of Brassica and provide an alternative method for the detection of pollen drift and risk assessment of gene flow in Brassica species. 相似文献
30.
Xiaoqing Guo Liwei Zhang Mingli Wu Na Wang Yanfeng Liu Limian Er Shunping Wang Yang Gao Weifang Yu Hui Xue Zhibin Xu Shijie Wang 《Molecular biology reports》2010,37(1):219-225
DNMT3B is an important enzyme to modulate the methylation status in mammalian cells. The aim of this study is to investigate the correlation of the DNMT3B G39179T polymorphism with the susceptibilities of colorectal adenomatous polyps and adenocarcinoma. This case-control study included 146 colorectal adenomatous polyps, 170 colorectal adenocarcinoma patients, and 157 normal controls. DNMT3B polymorphism was analyzed by polymerase chain reaction-restriction fragment length polymorphism analysis. Family history of colorectal cancer significantly increases the risk of developing colorectal adenomatous polyps and adenocarcinoma. The genotype frequency of DNMT3B polymorphism (T/T and G/T + G/G) in adenocarcinoma patients was significantly different from that in controls (P value = 0.01). Compared with DNMT3B T/T genotype, the G allelotype (G/T + G/G genotype) had lower risk to develop colorectal adenocarcinoma (OR = 0.50, 95% CI = 0.29–0.87); while there was no significant difference between the colorectal adenomatous polyps patients and controls (OR = 0.63, 95% CI = 0.37–1.09), although descending tendency could be found in this polyps group. In the stratification analysis, a significant association was confined to subgroups of age < 55 (OR = 0.31, 95% CI = 0.12–0.84) and males (OR = 0.35, 95% CI = 0.17–0.71). Meanwhile, combined G/T + G/G genotypes were found to have a lower risk in non-drinkers to develop both colorectal adenomatous polyps and adenocarcinoma (OR = 0.54, 95% CI = 0.31–0.96 and OR = 0.48, 95% CI = 0.27–0.84, respectively). This study also showed a distinct difference in the distribution of DNMT3B G39179T SNP in different ethnics. DNMT3B G39179T SNP may be a potential genetic susceptibility factor for adenocarcinoma of the colon, especially in younger Chinese Han non-drinker men. 相似文献