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401.
Alveolar macrophages (AM) which are separated into four fractionated subpopulations (I, II, III and IV), represented differential immunohistochemical staining with antibody against pulmonary surfactant protein A (SP-A). In light microscopy, the least dense AM (fraction I) were intensely stained with antibody to SP-A in numerous granules of the cytoplasm, whereas the most dense cells (fraction IV) showed immuno-reactivity with the antibody in several granules distributed in the spreading and elongating cytosol. By Western blot analysis, antibody to SP-A recognized a triplet of nature molecules of SP-A in AM lysate. However, the antigen of the AM lysate almost disappeared when the cells were cultured for more than two days, which indicate that AM do not synthesize SP-A and have digested intracellular SP-A during the cultivation. Immunoelectron microscopically, AM of fraction IV sometimes had very large vacuoles including lamellar body-like structures, probably pulmonary surfactant immediately after taken up from the alveolar lumen by them, which were heavily deposited with gold particles indicating antigenic site of SP-A. Whereas cells of fraction I contained numerous cytoplasmic vacuoles that were frequently labelled with the immuno-gold particles and were not associated with lamellar body-like structures, which may indicate that the materials in the vacuoles are digesting. The results of this experiments suggest that pulmonary surfactant, layered on the alveolar epithelium, is in part taken up by higher dense AM and is digested during a process of their maturation in the direction of lower dense cells, which undergo an important role of metabolism of pulmonary surfactant by AM subpopulations.  相似文献   
402.
Blood shortages for transfusion are global issues of grave concern. As in vitro manufactured platelets are promising substitutes for blood donation, recent research has shown progresses including different cell sources, different bioreactors, and three-dimensional materials. The first-in-human clinical trial of cultured platelets using induced pluripotent stem cell-derived platelets began in Japan and demonstrated its quality, safety, and efficacy. A novel bioreactor with fluid motion for platelet production has been reported. Herein, we discuss various cell sources for blood cell production, recent advances in manufacturing processes, and clinical applications of cultured blood.  相似文献   
403.
Within the nematode class Chromadorea, the suborder Tylenchina is an ecologically and morphologically diverse assemblage of nematodes that includes free‐living microbivores, fungivores and various types of plant parasites. A recent nematode classification system based largely on SSU rDNA phylogenetic trees classified suborder Tylenchina to include four infraorders: Panagrolaimomorpha, Cephalobomorpha, Tylenchomorpha and Drilonematomorpha, and phylogenetic relationships among species of these infraorders have not always been robustly supported. In this study, we determined the complete mitochondrial genome sequences of three Tylenchina species (Aphelenchus avenae [Aphelenchidae, Tylenchomorpha], Halicephalobus gingivalis, Panagrellus redivivus [Panagrolaimomorpha]) and the partial genome sequence of Acrobeles complexus (Cephalobomorpha) and used these sequences to infer phylogenetic relationships among representatives of the Tylenchina and other nematodes. Phylogenetic analysis of amino acid sequences for 12 protein‐coding genes of 100 nematode species supports monophyly of: Chromadorea, Spiruromorpha, Oxyuridomorpha, Ascarididae + Toxocaridae + Anisakidae, Meloidogynidae + Pratylenchidae + Heteroderidae and Aphelenchoidea. Bayesian and maximum‐likelihood analyses also show the nested position of Diplogasteromorpha within Rhabditomorpha, and Rhigonematomorpha within Ascaridomorpha. These analyses also show non‐monophyly of: clade III, Ancylostomatidae, Panagrolaimomorpha, Tylenchina and Tylenchomorpha. Reconstructed mitochondrial genome phylogeny also revealed that among two main Tylenchomorpha groups, the monophyletic group representing Aphelenchoidea species was sister to the large clade consisting of Ascaridomorpha, Diplogasteromorpha, Rhabditomorpha and Rhigonematomorpha and some Panagrolaimomorpha species, whereas Tylenchoidea species were sister to the most inclusive assemblage containing all infraordinal groups of Chromadorea, except for P. redivivus (Panagrolaimomorpha) and Acrobeles complexus (Cephalobomorpha). The monophyly of Aphelenchoidea (i.e. sister relationship between Aphelenchidae and Aphelenchoididae) recovered in this study indicates that similarity in certain aspects of pharyngeal structure between these two families appears best explained by common ancestry, rather than convergent evolution.  相似文献   
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We determined the complete mitochondrial genome sequence of Rhigonema thysanophora, the first representative of Rhigonematomorpha, and used this sequence along with 57 other nematode species for phylogenetic analyses. The R. thysanophora mtDNA is 15 015 bp and identical to all other chromadorean nematode mtDNAs published to date in that it contains 36 genes (lacking atp8) encoded in the same direction. Phylogenetic analyses of nucleotide and amino acid sequence data for the 12 protein‐coding genes recovered Rhigonematomorpha as the sister group to the heterakoid species, Ascaridia columbae (Ascaridomorpha). The organization of R. thysanophora mtDNA resembles the most common pattern for the Rhabditomorpha+Ascaridomorpha+Diplogasteromorpha clade in gene order, but with some substantial gene rearrangements. This similarity in gene order is in agreement with the sequence‐based analyses that indicate a close relationship between Rhigonematomorpha and Rhabditomorpha+Ascaridomorpha+Diplogasteromorpha. These results are consistent with certain analyses of nuclear SSU rDNA for R. thysanophora and some earlier classification systems that asserted phylogenetic affinity between Rhigonematomorpha and Ascaridomorpha, but inconsistent with morphology‐based phylogenetic hypotheses that suggested a close (taxonomic) relationship between rhigonematomorphs and oxyuridomorphs (pinworms). These observations must be tempered by noting that few rhigonematomorph species have been sequenced and included in phylogenetic analyses, and preliminary studies based on SSU rDNA suggest the group is not monophyletic. Additional mitochondrial genome sequences of rhigonematids are needed to characterize their phylogenetic relationships within Chromadorea, and to increase understanding of mitochondrial genome evolution.  相似文献   
408.
A new macropolycycle, 2,13-dimethyl-1,5,12,16-tetraazapentacyclo[14.6.2.25.12.06.11.017.22]hexacosane (L3), has been prepared by the reaction of 3,14-dimethyl-2,6,13,17-tetraazatricyclo[16.4.0.07.12]docosane (L1) with 1-bromo-2-chloroethane. The macropolycycle readily reacts with anhydrous copper(II) ion to yield [CuL3]2+ in dry methanol but does not with nickel(II) ion, showing a high copper(II) ion selectivity. Crystal structure of [CuL3](ClO4)2 shows that the complex has a distorted square-planar coordination polyhedron with a trans-IV type N-conformation. The Cu-N distances [1.989(3) and 2.015(3) Å] of [CuL3](ClO4)2 are distinctly shorter than those of [CuL1](ClO4)2 and other related macrocyclic copper(II) complexes. The d-d transition band for [CuL3](ClO4)2 is observed at 447 nm, which is ca. 40 nm shorter than that for [CuL1](ClO4)2.  相似文献   
409.
Finding an effective method to regenerate muscle is a growing issue in the orthopedic field. Platelet-rich plasma (PRP) has recently been considered for therapeutic use due to its capacity to induce proliferation of myogenic progenitor cells (MPCs). Adipose-derived stem cells (ASCs) and its extract are regarded as a promising treatment for various disorders within the orthopedic field but their therapeutic relevance in the muscle regeneration is poorly investigated. In this study, rabbit MPCs were cultured from the supraspinatus of rabbit and characterized by myogenic markers. To investigate the paracrine effect of ASCs on MPCs, coculture experiments were performed. In order to see the anabolic effect of ASC-extracts (ASC-ex) in MPCs, cell proliferation assays were performed and compared with the PRP-added condition. Coculture experiment showed ASCs had an anabolic paracrine effect on proliferation of MPCs. PRP had a positive effect on proliferation of MPCs when compared to the control (100?±?7.4% vs 195.2?±?19.2%, p?p?p?p?相似文献   
410.
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