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81.
Machado CM Schenka A Vassallo J Tamashiro WM Gonçalves EM Genari SC Verinaud L 《Cancer cell international》2005,5(1):13
A human malignant continuous cell line, named NG97, was recently established in our laboratory. This cell line has been serially
subcultured over 100 times in standard culture media presenting no sign of cell senescence. The NG97 cell line has a doubling
time of about 24 h. Immunocytochemical analysis of glial markers demonstrated that cells are positive for glial fibrillary
acidic protein (GFAP) and S-100 protein, and negative for vimentin. Under phase-contrast microscope, cultures of NG97 showed
cells with variable morphological features, such as small rounded cells, fusiform cells (fibroblastic-like cells), and dendritic-like
cells. However, at confluence just small rounded and fusiform cells can be observed. At scanning electron microscopy (SEM)
small rounded cells showed heterogeneous microextentions, including blebs and filopodia. Dendritic-like cells were flat and
presented extensive prolongations, making several contacts with small rounded cells, while fusiform cells presented their
surfaces dominated by microvilli. 相似文献
82.
A mucosal IgA-mediated excretory immune system in vivo 总被引:5,自引:0,他引:5
Robinson JK Blanchard TG Levine AD Emancipator SN Lamm ME 《Journal of immunology (Baltimore, Md. : 1950)》2001,166(6):3688-3692
The capacity of mucosal IgA Abs to serve as an excretory immune system in vivo was investigated. Mice expressing a transgenic TCR were immunized intragastrically with the cognate Ag to elicit a vigorous mucosal IgA Ab response. Soon after i.v. challenge, Ag was detected within the epithelial cells of the small intestinal crypts and to a lesser degree within the epithelial cells higher up the villi, paralleling the gradient in expression of the polymeric Ig receptor and the transport of its ligand, oligomeric IgA. Uptake of Ag into the epithelial cells occurred only from the basolateral aspect and only when Ag complexed to IgA Ab could be present in the lamina propria. The results support the concept that local IgA Abs can excrete Ags from the body by transporting them directly through mucosal epithelial cells, using the same mechanism that transports free IgA into the mucosal secretions. 相似文献
83.
84.
Richard Schwameis Christoph Grimm Edgar Petru Camilla Natter Christine Staudigl Wolfgang Lamm Heinz Koelbl Michael Krainer Thomas Brodowicz Alexander Reinthaller Stephan Polterauer 《PloS one》2015,10(8)
Objective
C-reactive protein (CRP) has previously been shown to serve as a prognostic parameter in women with gynecologic malignancies. Due to the lack of valid prognostic markers for uterine leiomyosarcoma (ULMS) this study set out to investigate the value of pre-treatment CRP serum levels as prognostic parameter.Methods
Data of women with ULMS were extracted from databases of three Austrian centres for gynaecologic oncology. Pre-treatment CRP serum levels were measured and correlated with clinico-pathological parameters. Univariate and multivariable survival analyses were performed.Results
In total, 53 patients with ULMS were included into the analysis. Mean (SD) CRP serum level was 3.46 mg/dL (3.96). Solely, an association between pre-treatment CRP serum levels and tumor size (p = 0.04) but no other clinic-pathologic parameter such as tumor stage (p = 0.16), or histological grade (p = 0.07), was observed. Univariate and multivariable survival analyses revealed that CRP serum levels (HR 2.7 [1.1–7.2], p = 0.037) and tumor stage (HR 6.1 [1.9–19.5], p = 0.002) were the only independent prognostic factors for overall survival (OS) in patients with ULMS. Patients with high pre-treatment CRP serum levels showed impaired OS compared to women with low levels (5-year-OS rates: 22.6% and 52.3%, p = 0.007).Conclusion
High pre-treatment CRP serum levels were independently associated with impaired prognosis in women with ULMS and might serve as a prognostic parameter in these patients. 相似文献85.
86.
ML Jones 《Biotechnic & histochemistry》2013,88(3):155-159
The discovery of formaldehyde for preserving tissue structures produced a new dimension in microscopy. Preserving structure and morphology became important; therefore, identifying a proper fixing agent for particular structures, chemical entities, and tissues, also became important. The methods for demonstrating tissue structures evolved and were implemented with careful observation and documentation of the results and outcomes. Formalin was incorporated into many techniques, and provided helpful results in many cases and hindrances in others. The effects of formalin on the outcomes of routine and special staining techniques are reported here. 相似文献
87.
Ksepka DT Benton MJ Carrano MT Gandolfo MA Head JJ Hermsen EJ Joyce WG Lamm KS Patané JS Phillips MJ Polly PD Van Tuinen M Ware JL Warnock RC Parham JF 《Biology letters》2011,7(6):801-803
Divergence dating studies, which combine temporal data from the fossil record with branch length data from molecular phylogenetic trees, represent a rapidly expanding approach to understanding the history of life. National Evolutionary Synthesis Center hosted the first Fossil Calibrations Working Group (3-6 March, 2011, Durham, NC, USA), bringing together palaeontologists, molecular evolutionists and bioinformatics experts to present perspectives from disciplines that generate, model and use fossil calibration data. Presentations and discussions focused on channels for interdisciplinary collaboration, best practices for justifying, reporting and using fossil calibrations and roadblocks to synthesis of palaeontological and molecular data. Bioinformatics solutions were proposed, with the primary objective being a new database for vetted fossil calibrations with linkages to existing resources, targeted for a 2012 launch. 相似文献
88.
Nitric oxide (NO) has been reported to act both as a destructive and a protective agent in the pathogenesis of the injuries
that occur during hypoxia/reoxygenation (H/R). It has been suggested that this dual role of NO depends directly on the isoform
of NO synthase (NOS) involved. In this work, we investigate the role that NO derived from endothelial NOS (eNOS) plays in
cardiac H/R-induced injury. Wistar rats were submitted to H/R (hypoxia for 30 min; reoxygenation of 0 h, 12 h and 5 days),
with or without prior treatment using the selective eNOS inhibitor l-NIO (20 mg/kg). Lipid peroxidation, apoptosis and protein nitration, as well as NO production (NOx), were analysed. The results
showed that l-NIO administration lowered NOx levels in all the experimental groups. However, no change was found in the lipid peroxidation
level, the percentage of apoptotic cells or nitrated protein expression, implying that eNOS-derived NO may not be involved
in the injuries occurring during H/R in the heart. We conclude that l-NIO would not be useful in alleviating the adverse effects of cardiac H/R. 相似文献
89.
Regional pulmonary blood flow in dogs under zone 3 conditions was measured in supine and prone postures to evaluate the linear gravitational model of perfusion distribution. Flow to regions of lung that were 1.9 cm3 in volume was determined by injection of radiolabeled microspheres in both postures. There was marked perfusion heterogeneity within isogravitational planes (coefficient of variation = 42.5%) as well as within gravitational planes (coefficient of variation = 44.2 and 39.2% in supine and prone postures, respectively; P = 0.02). On average, vertical height explained only 5.8 and 2.4% of the flow variability in the supine and prone postures, respectively. Whereas the gravitational model predicts that regional flows should be negatively correlated when measured in supine and prone postures, flows in the two postures were positively correlated, with an r2 of 0.708 +/- 0.050. Regional perfusion as a function of distance from the center of a lung explained 13.4 and 10.8% of the flow variability in the supine and prone postures, respectively. A linear combination of vertical height and radial distance from the centers of each lung provided a better-fitting model but still explained only 20.0 and 12.0% of the flow variability in the supine and prone postures, respectively. The entire lung was searched for a region of contiguous lung pieces (22.8 cm3) with high flow. Such a region was found in the dorsal area of the lower lobes in six of seven animals, and flow to this region was independent of posture. Under zone 3 conditions, neither gravity nor radial location is the principal determinant of regional perfusion distribution in supine and prone dogs. 相似文献
90.