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11.
Bone osteoblasts and osteocytes express large amounts of connexin (Cx) 43, the component of gap junctions and hemichannels. Previous studies have shown that these channels play important roles in regulating biological functions in response to mechanical loading. Here, we characterized the distribution of mRNA and protein of Cx43 in mechanical loading model of tooth movement. The locations of bone formation and resorption have been well defined in this model, which provides unique experimental systems for better understanding of potential roles of Cx43 in bone formation and remodeling under mechanical stimulation. We found that mechanical loading increased Cx43 mRNA expression in osteoblasts and bone lining cells, but not in osteocytes, at both formation and resorption sites. Cx43 protein, however, increased in both osteoblasts and osteocytes in response to loading. Interestingly, the upregulation of Cx43 protein by loading was even more pronounced in osteocytes compared to other bone cells, with an appearance of punctate staining on the cell body and dendritic process. Cx45 was reported to be expressed in several bone cell lines, but here we did not detect the Cx45 protein in the alveolar bone cells. These results further suggest the potential involvement of Cx43-forming gap junctions and hemichannels in the process of mechanically induced bone formation and resorption. 相似文献
12.
Igor Marjanovič Saša Haberl Damijan Miklavčič Maša Kandušer Mojca Pavlin 《The Journal of membrane biology》2010,236(1):97-105
Knowledge of the parameters which influence the efficiency of gene electrotransfer has importance for practical implementation
of electrotransfection for gene therapy as well as for better understanding of the underlying mechanism. The focus of this
study was to analyze the differences in gene electrotransfer and membrane electropermeabilization between plated cells and
cells in a suspension in two different cell lines (CHO and B16F1). Furthermore, we determined the viability and critical induced
transmembrane voltage (ITVc) for both cell lines. In plated cells we obtained relatively little difference in electropermeabilization and gene electrotransfection
between CHO and B16F1 cells. However, significant differences between the two cell lines were observed in a suspension. CHO
cells exhibited a much higher gene electrotransfection rate compared to B16F1 cells, whereas B16F1 cells reached maximum electropermeabilization
at lower electric fields than CHO cells. Both in a suspension and on plated cells, CHO cells had a slightly better survival
rate at higher electric fields than B16F1 cells. Calculation of ITVc in a suspension showed that, for both electropermeabilization and gene electrotransfection, CHO cells have lower ITVc than B16F1 cells. In all cases, ITVc for electropermeabilization was lower than ITVc for gene electrotransfer, which is in agreement with other studies. Our results show that there is a marked difference in
the efficiency of gene electrotransfer between suspended and plated cells. 相似文献
13.
The prevalence of overweight and obesity among Croatian hospitalized coronary heart disease patients
Vrazić H Sikić J Lucijanić T Starcević B Samardzić P Trsinski D Sutalo K Mirat J Zaputović L Bergovec M 《Collegium antropologicum》2012,36(Z1):211-216
The aim of this article was to investigate the prevalence of overweight and obesity using selected anthropometric variables in a sample of hospitalized coronary heart disease (CHD) patients in Croatia (N = 1,298). Prevalence of overweight and obesity in surveyed patient population was high: 48.2% of participants were overweight and 28.6% were obese according to their body mass index; measured through waist-to-hip ratio 54.5% of participants were centrally obese. These data on prevalences of overweight, obesity and central obesity show that although there are some reassuring trends, there is still considerable amount of work to be done if the prevalence of this cardiovascular risk factor is to be reduced further among Croatian CHD patients. While the prevalence of obesity seems to be on the decline, the prevalence of overweight is rising, which may be just an early warning sign of an incoming wave of obesity epidemic in future years. 相似文献
14.
We described the use of a new chemical substance Sodium nucleinate (SN) as an immunomodulatory substance exhibiting antiinflammatory properties. Sodium nucleinate (SN) registrated in Russian Federation as Tamerit, is 2-amino-1,2,3,4-tetrahydrophthalazine-1,4-dione sodium salt dihydrate, derivative of well known chemical substance luminol. To comprehend the mechanisms of SN immunomodulatory activity, we examined the SN modulation of the oxidative burst responses of whole blood human monocytes and polimorphonuclear cells (PMC) stimulated with phorbol 12-myristate 13-acetate (PMA) or E. coli suspension in vitro. SN did not inhibit the proportion of neutrophils and monocytes phagocytosing E. coli. Oxidative burst responses of monocytes stimulated with PMA were strongly inhibited at SN concentration ranging from 10-500 mg/ml, less efficient inhibitor was SN in E. coli stimulated monocytes (inhibition range was from 50-500 mg/ml SN). SN inhibited PMC oxidative burst only in range 100-500 mg/ml SN. In conclusion, we found SN as an efficient inhibitor of oxidative burst in monocytes. Since ROS generation in monocytes/macrophages has been found to be important for LPS-driven production of several proinflammatory cytokines, SN may exsert its antiinflammatory effects through monocyte/macrophage oxidative burst inhibition. 相似文献
15.
Recombinant production of therapeutically active proteins has become a central focus of contemporary life science research. These proteins are often produced in mammalian cells, in order to obtain products with post-translational modifications similar to their natural counterparts. However, in cases where a fast and flexible system for recombinant production of proteins is needed, the use of mammalian cells is limited. The baculoviral insect cell system has proven to be a powerful alternative for the expression of a wide range of recombinant proteins in short time frames. The major drawback of baculoviral systems lies in the inability to perform mammalian-like glycosylation required for the production of therapeutic glycoproteins. In this study we integrated sequences encoding Caenorhabditis elegans N-acetylglucosaminyltransferase II and bovine β1,4-galactosyltransferase I into the backbone of a baculovirus genome. The thereby generated SweetBac virus was subsequently used for the production of the human HIV anti-gp41 antibody 3D6 by integrating heavy and light chain open reading frames into the SweetBac genome. The parallel expression of target genes and glycosyltransferases reduced the yield of secreted antibody. However, the overall expression rate, especially in the recently established Tnao38 cell line, was comparable to that of transient expression in mammalian cells. In order to evaluate the ability of SweetBac to generate mammalian-like N-glycan structures on 3D6 antibody, we performed SDS-PAGE and tested for the presence of terminal galactose using Riccinus communis agglutinin I. The mammalianised variants of 3D6 showed highly specific binding to the lectin, indicating proper functionality. To confirm these results, PNGase A released N-glycans were analyzed by MALDI-TOF-MS and shown to contain structures with mainly one or two terminal galactose residues. Since the presence of specific N-glycans has an impact on antibodies ability to exert different effector functions, we tested the binding to human Fc gamma receptor I present on U937 cells. 相似文献
16.
Majerović M Augustin G Jelincić Z Buković D Kekez T Matosević P Smud D Kinda E Golem AZ 《Collegium antropologicum》2008,32(3):703-707
Radiofrequency ablation (RFA) is one treatment modality for unresectable liver metastases. Patients with hepatic malignancies (n = 24) underwent elective RFA. All tumors were ablated with a curative intent, with a margin of 1 cm, in a single session of RFA. The median diameter of tumor was 3.1 cm (range 1.7-6.9 cm). Studied patients were not candidates for resection due to multifocal hepatic disease, extrahepatic disease, proximity to major vascular structures or presence of cirrhosis with functional hepatic reserve inadequate to tolerate major hepatic resection. Complete tumor necrosis was achieved in 87.5% and tumor recurred in 3 patients (12.5%) with lesions larger than 5 cm. Distant intrahepatic recurrence was diagnosed in another 4 (16.7%). Distant metastases were found in 7 (29.2%) patients. Four of these 7 patients had also distant intrahepatic recurrence of disease. Two and 5-years survival rates were 41.7% (10 patients) and 8.3% (2 patients) respectively. RFA is safe and effective option for patients with unresectable hepatic malignancies smaller than 5 cm without distant metastatic disease. RF ablation resulted in complete tumor necrosis in 87.5% with 2 and 5-years survival rates much higher than with chemotherapy alone or only supportive therapy, when survival is measured in weeks or months. If RFA is unavailable, percutaneous ethanol injection therapy can be done but with inferior survival rates. 相似文献
17.
Joao H. F. Pedra Sukanya Narasimhan Dubravko Rendić Kathleen DePonte Lesley Bell‐Sakyi Iain B. H. Wilson Erol Fikrig 《Cellular microbiology》2010,12(9):1222-1234
Fucosylated structures participate in a wide range of pathological processes in eukaryotes and prokaryotes. The impact of fucose on microbial pathogenesis, however, has been less appreciated in arthropods of medical relevance. Thus, we used the tick‐borne bacterium Anaplasma phagocytophilum– the agent of human granulocytic anaplasmosis to understand these processes. Here we show that A. phagocytophilum uses α1,3‐fucose to colonize ticks. We demonstrate that A. phagocytophilum modulates the expression of α1,3‐fucosyltransferases and gene silencing significantly reduces colonization of tick cells. Acquisition but not transmission of A. phagocytophilum was affected when α1,3‐fucosyltransferases were silenced during tick feeding. Our results uncover a novel mechanism of pathogen colonization in arthropods. Decoding mechanisms of pathogen invasion in ticks might expedite the development of new strategies to interfere with the life cycle of A. phagocytophilum. 相似文献
18.
Studying human impacts on riverine systems is challenging due to the natural diversity and multiple stressors that are co-occurring.
The term stressor(s) refers to variable(s) of anthropogenic landscape changes and local abiotic stream conditions that reflect human activities.
We compared the effects of different stressors and natural (typology) factors on benthic invertebrate assemblages in Slovenian rivers. A total of 270 river sites located in four European ecoregions
were sampled, covering the gradient of human perturbation ranging from (near)natural to highly degraded/polluted. Stressors
commonly affecting running waters were grouped into management-relevant stressor-groups: land use (percentage of urban, intensive and non-intensive agricultural, and natural land use in the catchment and sub-catchment),
eutrophication (in-stream concentrations of phosphorus and nitrogen compounds) and other stressors (e.g., organic pollution, hydromorphological alteration). We compared the effects of the stressor-groups on invertebrate
assemblages using partial Canonical Correspondence Analysis and tested the explanatory power of each stressor-group using
typology variables as covariates. Stressors and typology variables showed high independent effects (40–65%) on invertebrate assemblages despite considerable joint effects from land use and typology. Stressors’ pure effects accounted for 70%, and interactions among the stressor-groups made up the remaining 30% of the total
explained variability. Altogether, this study gives a good perspective on the ability to separate the effects of anthropogenic
stressors from natural causes, as well as to separate effects among groups of stressors. Against this background, we advocate
stressor-specific analyses to provide or improve guidelines for selecting appropriate measures to enhance the river status. 相似文献
19.
Amundsen BH Ericsson M Seland JG Pavlin T Ellingsen Ø Brekken C 《Laboratory animals》2011,45(1):31-37
Non-invasive imaging methods like echocardiography and magnetic resonance imaging (MRI) are very valuable in longitudinal follow-up studies of cardiac function in small animals. To be able to compare results from studies using different methods, and explain possible differences, it is important to know the agreement between these methods. As both self-gated high-field MRI and high-frequency echocardiography (hf-echo) M-mode are potential methods for evaluation of left ventricular (LV) function in healthy mice, our aim was to assess the agreement between these two methods. Fifteen healthy female C57BL/6J mice underwent both self-gated MRI and hf-echo during the same session of light isoflurane anaesthesia. LV dimensions were estimated offline, and agreement between the methods and reproducibility for the two methods assessed using Bland-Altman methods. In summary, hf-echo M-mode had better inter-observer repeatability than self-gated MRI for all measured parameters. Compared with hf-echo, systolic posterior wall thicknesses were significantly higher when measured by MRI, while diastolic anterior wall thicknesses were found to be significantly smaller. MRI measurements of diastolic LV diameter were also higher using MRI, resulting in larger fractional shortening values compared with the values obtained by hf-echo. In conclusion, hf-echo M-mode is easy to apply, has high temporal and spatial resolution, and good reproducibility. Self-gated MRI might be advantageous in cases of abnormal LV geometry and heterogeneous regional myocardial function, especially with improvements in spatial resolution. The moderate agreement between the methods must be taken into account when comparing studies using the two modalities. 相似文献
20.
Prof. Dr. Josip Tišljar M.Sc. Igor Vlahović Dr. Ivo Velić Dr. Dubravko Matičec Dr. Julie Robson 《Facies》1998,38(1):137-151
Summary During the Late Albian, Early and Middle Cenomanian in the NW part of the Adriatic Carbonate Platform (presentday Istria)
specific depositional systems characterised by frequent lateral and vertical facies variations were established within a formerly
homogeneous area, ranging from peritidal and barrier bars to the offshore-transition zone. In southern Istria this period
is represented by the following succession: thin-bedded peritidal peloidal and stromatolitic limestones (Upper Albian); well-bedded
foreshore to shoreface packstones/grainstones with synsedimentary dliding and slumping (Vraconian-lowermost Cenomanian); shoreface
to off-shore storm-generated limestones (Lower Cenomanian); massive off-shore to shoreface carbonate sand bodies (Lower Cenomanian);
prograding rudist bioclastic subaqueous dunes (Lower to Middle Cenomanian); rudist biostromes (Lower to Middle Cenomanian),
and high-energy rudist and ostreid coquina beds within skeletal wackestones/packstones (Middle Cenomanian).
Rapid changes of depositional systems near the Albian/Cenomanian transition in Istria are mainly the result of synsedimentary
tectonics and the establishment of extensive rudist colonies producing enormous quantities of bioclastic material rather than
the influence of eustatic changes. Tectonism is evidenced by the occurrence of sliding scars, slumps, small-scale synsedimentary
faults and conspicuous bathymetric changes in formerly corresponding environments. Consequently, during the Early Cenomanian
in the region of southern Istria, a deepening of the sedimentary environments occurred towards the SE, resulting in the establishment
of a carbonate ramp system. Deeper parts of the ramp were below fair-weather wave base (FWWB), while the shallower parts were
characterised by high-energy environments with extensive rudist colonies, and high organic production leading to the progradation
of bioclastic subaqueous dunes. This resulted in numerous shallowing- and coarsening-upwards clinostratified sequences completely
infilling formerly deeper environments, and the final re-establishment of the shallow-water environments over the entire area
during the Middle Cenomanian. 相似文献