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排序方式: 共有466条查询结果,搜索用时 421 毫秒
111.
112.
Politi EN Lazaris AC Kavantzas N Koutselini H 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2003,25(3):169-176
OBJECTIVE: To investigate the morphometric properties of tumor cells in combination with the expression of 5 immunomarkers, quantitatively evaluated by image analysis, in a series of 60 non-small cell lung carcinomas (NSCLCs) and to assess their prognostic significance. STUDY DESIGN: Tissue sections from 60 NSCLCs were assessed for the expression of p53, Ki-67, bcl-2, bax and FasL using immunohistochemistry and antibodies. Correlations between morphometric features and clinicopathologic variables, including overall survival and the expression of the above markers, were statistically investigated. RESULTS: Major and minor axis nuclear values, as well as nuclear area and perimeter values, were positively interrelated. No statistically significant correlations were observed between nuclear morphometry and any of the clinicopathologic parameters. p53 Accumulation, when quantitatively estimated, displayed a positive correlation with major axis (P = .008), minor axis (P = .06), nuclear perimeter (P = .006) and mainly nuclear area values (P = .003). Bcl-2- and bax-quantified immunostaining demonstrated a weak negative correlation with shape factor values (P = .039 and P = .025, respectively). Univariate and multivariate analysis showed that stage was the only significant predictor of survival in all patients. In univariate statistical analysis there was a trend between worse survival and shape factor values < 0.8 (P = .0791); this trend almost reached statistical significance in the subgroup of squamous cell carcinomas (P = .0570). CONCLUSION: p53 Accumulation, when quantified, appears to be positively linked with nuclear morphometric values. The prognostic significance of shape factor in NSCLC warrants further investigation. 相似文献
113.
Politi EN Lazaris AC Alexopoulou D Lambropoulou S Kavantzas N Koutselini H 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2004,26(4):187-193
OBJECTIVE: To detect argyrophilic nucleolar organizer regions (AgNORs) in ThinPrep (Cytyc Corp., Boxborough, Massachusetts, U.S.A.) liver fine needle aspiration (FNA) specimens and to define the diagnostic value of their quantitative analysis in the evaluation of hepatic lesions. STUDY DESIGN: ThinPrep liquid-based FNA biopsy specimens from 49 malignant and benign liver lesions were resampled, fixed in 95% ethanol and stained with the AgNOR technique in accordance with the 1-step colloid method. The specimens included 11 benign and 38 malignant lesions (23 poorly differentiated hepatocellular carcinomas [HCCs] and 15 poorly differentiated metastatic adenocarcinomas [MCs]). Morphometric analysis was performed using a Zeiss Axiolab microscope (Carl Zeiss GmbH, Jena, Germany) with a mechanical stage fitted with a Sony-iris CCD videocamera (Tokyo, Japan). The videocamera was connected to a Pentium III P/C (Intel Corp., Santa Clara, California, U.S.A.) loaded with the appropriate image analysis software. The measurements were performed with ImageScan software (Jandel Scientific, Erkrath, Germany). The number of AgNORs per nucleus (NN) and the total area per nucleus occupied by AgNORs (AR) were calculated semiautomatically. Statistical analysis was performed using the SPSS software package (Chicago, Illinois, U.S.A.). RESULTS: The least significant deviance test for multiple comparisons revealed that NN differed significantly between the 3 groups of samples examined (P < .0001). The mean NN values in HCCs and MCs were significantly different (P < .0001). Logistic regression model demonstrated that as NN increased, the probability of a MC diagnosis decreased (<4%). AR values were different at a statistically significant level only between benign and malignant specimens (P = .00006), not between HCCs and MCs (P = .933). CONCLUSION: Quantitative analysis of AgNORs in ThinPrep specimens could be a diagnostically useful method in liver disease. 相似文献
114.
Koufaki M Calogeropoulou T Rekka E Chryselis M Papazafiri P Gaitanaki C Makriyannis A 《Bioorganic & medicinal chemistry》2003,11(23):5209-5219
We have synthesized a series of hybrid compounds combining the pharmacophoric redox moieties of vitamin E and key features responsible for the antiarrhythmic properties of the class I antiarrhythmics procainamide and lidocaine. Procainamide analogue (2a) and lidocaine analogues (14a) and (14b) are very strong inhibitors of lipid peroxidation. All analogues tested at 100 or 30 microM enhanced the post ischemic recovery without inducing ventricular fibrillations while there was no evidence in our experiments for drug-induced pro-arrhythmia. In addition, they induced a widening of the QRS intervals. Our data suggest that the efficacy of the new compounds in preventing reperfusion arrhythmias could be attributed to their combined effects involving inhibition of free radical mediated damage coupled with antiarrhythmic properties. 相似文献
115.
Imaging the Brain Marijuana Receptor: Development of a Radioligand that Binds to Cannabinoid CB1 Receptors In Vivo 总被引:2,自引:0,他引:2
S. John Gatley †Ruoxi Lan ‡Nora D. Volkow Naomi Pappas Payton King Christopher T. Wong Andrew N. Gifford Beatrice Pyatt Stephen L. Dewey †§Alexandros Makriyannis 《Journal of neurochemistry》1998,70(1):417-423
Abstract: The major active ingredient of marijuana, (−)-Δ9 -tetrahydrocannabinol, exerts its psychoactive effects via binding to cannabinoid CB1 receptors, which are widely distributed in the brain. Radionuclide imaging of CB1 receptors in living human subjects would help explore the presently unknown physiological roles of this receptor system, as well as the neurochemical consequences of marijuana dependence. Currently available cannabinoid receptor radioligands are exceedingly lipophilic and unsuitable for in vivo use. We report the development of a novel radioligand, [123 I]AM281{ N -(morpholin-4-yl)-5-(4-[123 I]iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1 H -pyrazole-3-carboxamide}, that is structurally related to the CB1-selective antagonist SR141716A [ N -(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1 H -pyrazole-3-carboxamide]. Baboon single photon emission computed tomography studies, mouse brain dissection studies, and ex vivo autoradiography in rat brain demonstrated rapid passage of [123 I]AM281 into the brain after intravenous injection, appropriate regional brain specificity of binding, and reduction of binding after treatment with SR141716A. AM281 has an affinity in the low nanomolar range for cerebellar binding sites labeled with [3 H]SR141716A in vitro, and binding of [123 I]AM281 is inhibited by several structurally distinct cannabinoid receptor ligands. We conclude that [123 I]AM281 has appropriate properties for in vivo studies of cannabinoid CB1 receptors and is suitable for imaging these receptors in the living human brain. 相似文献
116.
Nikolaos Biris Morfis Abatzis John V Mitsios Maria Sakarellos-Daitsiotis Constantinos Sakarellos Demokritos Tsoukatos Alexandros D Tselepis Lambros Michalis Dimitrios Sideris Georgia Konidou Ketty Soteriadou Vassilios Tsikaris 《European journal of biochemistry》2003,270(18):3760-3767
alpha(IIb)beta(3), a member of the integrin family of adhesive protein receptors, is the most abundant glycoprotein on platelet plasma-membranes and binds to adhesive proteins via the recognition of short amino acid sequences, for example the ubiquitous RGD motif. However, elucidation of the ligand-binding domains of the receptor remains controversial, mainly owing to the fact that integrins are conformationally labile during purification and storage. In this study, a detailed mapping of the extracellular region of the alpha(IIb) subunit is presented, using overlapping 20-peptides, in order to identify the binding sites of alpha(IIb) potentially involved in the platelet-aggregation event. Regions alpha(IIb) 313-332, alpha(IIb) 265-284 and alpha(IIb) 57-64 of alpha(IIb)beta(3) were identified as putative fibrinogen-binding domains because the corresponding peptides inhibited platelet aggregation and antagonized fibrinogen association, possibly by interacting with this ligand. The latter is further supported by the finding that the above peptides did not interfere with the binding of PAC-1 to the activated form of alpha(IIb)beta(3). Furthermore, alpha(IIb) 313-332 was found to bind to fibrinogen in a solid-phase binding assay. It should be emphasized that all the experiments in this study were carried out on activated platelets and consequently on the activated form of this integrin receptor. We hypothesize that RAD and RAE adhesive motifs, encompassed in alpha(IIb) 313-332, 265-284 and 57-64, are capable of recognizing complementary domains of fibrinogen, thus inhibiting the binding of this ligand to platelets. 相似文献
117.
118.
ARB: a software environment for sequence data 总被引:15,自引:2,他引:13
Ludwig W Strunk O Westram R Richter L Meier H Yadhukumar Buchner A Lai T Steppi S Jobb G Förster W Brettske I Gerber S Ginhart AW Gross O Grumann S Hermann S Jost R König A Liss T Lüssmann R May M Nonhoff B Reichel B Strehlow R Stamatakis A Stuckmann N Vilbig A Lenke M Ludwig T Bode A Schleifer KH 《Nucleic acids research》2004,32(4):1363-1371
119.
Visualization by live-cell microscopy of disruption of ND10 during herpes simplex virus type 1 infection 下载免费PDF全文
ND10 structures are disrupted during herpes simplex virus type 1 (HSV-1) infection by viral regulatory protein ICP0. The significance of this effect remains controversial, partly because of a report that high-level expression of the major ND10 promyelocytic leukemia (PML) protein precludes ND10 disruption yet does not inhibit HSV-1 infection. Here we demonstrate dramatic reorganization of ND10 during HSV-1 infection by live-cell microscopy, even in the presence of overexpressed PML. 相似文献
120.
Kostarelos K Emfietzoglou D Papakostas A Yang WH Ballangrud AM Sgouros G 《Journal of liposome research》2005,15(1-2):15-27
Liposomes have been widely used delivery systems, particularly relevant to the development of cancer therapeutics. Numerous liposome-based drugs are in the clinic or in clinical trials today against multiple tumor types; however, systematic studies of liposome interactions with solid or metastatic tumor nodules are scarce. This study is describing the in vitro interaction between liposomes and avascular human prostate (LNCaP-LN3) tumor spheroids. The ability of fluorescently labelled liposomal delivery systems of varying physicochemical characteristics to penetrate within multicellular tumor spheroids has been investigated by confocal laser scanning microscopy. A variety of liposome characteristics and experimental parameters were investigated, including lipid bilayer composition, duration of liposome-spheroid interaction, mean liposome size, steric stabilization of liposomes. Electrostatic binding between cationic liposomes and spheroids was very efficient; however, it impeded any significant penetration of the vesicles within deeper layers of the tumor spheroid. Small unilamellar liposomes of neutral surface character did not bind as efficiently but exhibited enhanced penetrative transport capabilities closer to the tumor core. Polymer-coated (sterically stabilised) liposomes exhibited almost no interaction with the spheroid, indicating that their limited diffusion within avascular tissues may be a limiting step for their use against micrometastases. Multicellular tumor spheroids were used as models of solid tumor interstitium relevant to delivery systems able to extravasate from the microcapillaries or as models of prevascularized micrometastases. This study illustrates that interactions between liposomes and other drug delivery systems with multicellular tumor spheroids can offer critically important information with respect to optimizing solid or micrometastatic tumor delivery and targeting strategies. 相似文献