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71.
Bánkfalvi Á Piffkó J Öfner D Dreier R Böcker W Werner K 《Pathology oncology research : POR》1996,2(1-2):71-77
Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic
digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in
immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating
methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the
microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity
in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced
in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2
antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully
for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory
molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar
organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized
AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric
study group as the standardized method for AgNOR analysis in archival material. 相似文献
72.
Piffkó J Bánkfalvi Á Öfner D Tötsch M Berens A Joos U Böcker W Schmid KW 《Pathology oncology research : POR》1996,2(1-2):37-42
Formalin fixed and paraffin embedded samples from 36 squamous cell carcinomas of the larynx and the oral cavity (pT2N0M0, R0) surrounded by non-tumorous mucosa were studied immunohistochemically using a panel of four different anti-p53 antibodies
(CM1, PAbl801, D07, PAb240), a monoclonal anti-mdm2 antibody and MIB1, following wet autoclave antigen retrieval. P53 immunoreactivity
was detected in 11/14 laryngeal and in 9/22 oral carcinomas. All p53 positive oral, and all but one laryngeal tumors revealed
mdm2 positivity as well, whereas in p53 negative tumors 4/12 and 1/3 mdm2 immunopositive cases were demonstrated, respectively.
MIB1 labeling indices of the tumors ranged between 18% – 64% in p53 positive cases, and 10% – 53% in p53 negative ones. The
difference was not statistically significant. Close spatial coexpression of p53, mdm2 and MIB1 immunoreactivity was observed
at the invasive front of the carcinomas and in the basal and suprabasal layers of the non-tumorous epithelium in all p53 positive
cases. However, the MIB1 expression was similarly increased at the invasive margins in carcinomas lacking immunohistochemically
detectable p53 alterations. Our results strongly suggest that p53 overexpression does not necessarily correspond to increased
rate of proliferation, but rather to mdm2 overexpression and is largely dependent on the anatomical site in case of small
and localized squamous cell carcinomas of the head and neck region. 相似文献
73.
Michael Gottsauner-Wolf Johanna Schedimayer-Duit Gerold Porenta Marianne Gwechenberger Kurt Huber Dietmar Giogar Peter Probst Heinz Sochor 《European journal of nuclear medicine and molecular imaging》1996,23(12):1613-1618
Measurement of global left ventricular function is important in the follow-up of cardiac patients and is a good prognostic indicator in acute cardiac situations. We compared quantitative measurements of global left ventricular function made with radionuclide angiography (RNA) and contrast cardiac ventriculography (CVG) to visual semiquantitative estimates from two-dimensional echocardiographic images (2D-echo). Three hundred and thirty-nine consecutive patients who underwent RNA were assessed with 2D-echo within 3 months. In addition, 92 of these patients also underwent CVG (correlation of ejection fraction between CVG and RNA:r=0.82;P<0.0001). The RNA mean ejection fractions in the four 2D-echo groups (0=normal, 1=slightly, 2=moderate, or 3=severe reduced left ventricular function) differed markedly (P<0.0001); however, there was overlapping among the groups (2D-echo score/RNA ejection fraction: 0=57.3%±12.8%; 1=46.0%±12.9%; 2=29.6%±12.2%; and 3=24.6%±11.5%) and the difference between 2D-echo scores 2 and 3 was not significant. 2D-echo showed a good concordance in RNA classes (0=505; 1=35%–49%; 2=21%–34%; and 3=520% ejection fraction) 0 (133/166; 80%) and 3 (18/30; 60%) but low concordance in classes 1 (27/82; 33%) and 2 (21/61; 34%). For accurate assessment of global left ventricular ejection fraction, visual semiquantitative judgement of a 2D echocardiographic image is limited in comparison to CVG or RNA, especially in patients with a slight or moderate reduction in left ventricular ejection fraction. 相似文献
74.
75.
Kurt Krejcy Gunther Krumpl Hannes Todt Gerhard Raberger 《Naunyn-Schmiedeberg's archives of pharmacology》1992,346(2):213-218
Summary The aim of the present study was to investigate the dose-dependent antiarrhythmic efficacy of lidocaine against electrically induced tachycardias in conscious, chronically instrumented postinfarction dogs. Programmed electrical stimulation (PES) was performed in 16 dogs 8 to 21 days after a 4 h occlusion of the left anterior descending coronary artery (LAD). Infusion of saline in 8 control animals with sustained ventricular tachycardia (SVT) inducible at baseline did not affect subsequent inducibility. In the treatment group 7 of 8 animals responded with SVT and one exhibited ventricular fibrillation at baseline. After an initial bolus of 1 mg/kg lidocaine intravenously (i.v.), the drug was infused at infusion rates of 40, 80 and 120 g/kg/min (i.v.). During 80 g/kg/min lidocaine (mean plasma level 3.5 g/ml) 7 out of 8 animals displayed an antiarrhythmic response; both the lower and the higher infusion rate were associated with a smaller antiarrhythmic efficacy (3 of 8 animals responded to 40 g/kg/min and 4 of 8 to 120 g/kg/min). Licocaine did not affect ventricular refractory periods, but induced an increase in intraventricular conduction time at all infusion rates, from 66.2 ms at baseline to 67.7 ms (p<0.05), 67.7 ms (p<0.05), 70.0 ms (p<0.01) respectively.In conclusion the present study demonstrates that lidocaine is of considerable value in the management of PES-induced ventricular arrhythmias in the postinfarction phase. However there is only a small optimal therapeutic plasma level range, where lidocaine exhibits its antiarrhythmic efficacy against this type of arrhythmia; this makes a carefully titration of the drug necessary both in the experimental and in the clinical setting.
Send offprint requests to K. Krejcy at the above address 相似文献
76.
Kurt W. Pontasch John Cairns Jr. 《Archives of environmental contamination and toxicology》1991,20(1):103-112
A study was conducted to determine if contaminant-induced changes in macroinvertebrate communities in laboratory stream microcosms could be used to predict responses of these organisms in a natural stream receiving the same contaminant. Test organisms were transferred to the artificial streams in rock-filled containers previously colonized for 30 days upstream of the effluent outfall. The microcosms were exposed for 20 days to concentrations of the effluent that reflected those at field sites where macroinvertebrates were collected.The stream microcosms maintained most taxa at or above initial densities. However, adult insect emergence from the microcosms must be monitored during such studies. The relative sensitivity of species and the effluent concentrations causing changes in insect density were similar in the microcosms and the field. Mayflies were the most sensitive group, and densities in the microcosms were significantly (P 0.05) reduced at 1.0% or 10.0% effluent concentration depending on species. Conversely, chironomids densities were increased by exposure to the effluent. The mayflies responded at lower concentrations than acute tests withDaphnia magna would have predicted. 相似文献
77.
Kurt Freund MD DSc Robin Watson MEd Robert Dickey MD 《Sexual abuse : a journal of research and treatment》1991,4(1):93-105
The rationale for dividing the clinical spectrum of DSM-III-R male heterosexual gender identity disorder into three types was examined. The DSM-III-R category of fetishism for female attire, was included in the analysis. There were 266 male participants divided into three groups: 172 fetishists for female attire or gender identity patients, 52 androphiles, and 42 gynephiles. A 16 item questionnaire was used to examine the groups. A three factor scale ("Fetishism", "Gender Dysphoria" and "Androphilia") was derived from the questionnaire. Only the Gender Dysphoria Factor Scale successfully differentiated between all four conditions, supporting the notion that the three types of gender identity disorder represent a continuum of degree of severity of gender dysphoria. Defining two of the three types of gender identity disorder in terms of the patients' self-reports on fetishism, as DSM-III-R does, is therefore unnecessary. 相似文献
78.
Kurt Schneider Melvin R. Kinlow A. N. Galloway Don L. Ferro 《Child & youth care forum》1982,11(4):298-311
The effects of implementing the Teaching-Family Model in two community-based group homes were assessed through a series of pre-post measures. Data analysis indicates substantial positive change in youth social skills, program quality, youth and staff satisfaction levels, social climate, and staff accountability for care of the children.Requests for reprints, samples of the Staff Accountability Scale, and other forms or the questionnaires in this study should be addressed to Kurt Scheider at The Maryville Academy, 1150 North River Road, Des Plaines, IL 60016 相似文献
79.
80.
Petra Heinm?ller Christof Gross Kurt Beyser Claudia Schmidtgen Gerd Maass Michele Pedrocchi Josef Rüschoff 《Clinical cancer research》2003,9(14):5238-5243
PURPOSE: For the first time a large number (563) of non-small cell lung cancer (NSCLC) samples was used to compare three different technologies for the assessment of HER2 status. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were used for tumor tissue samples, and ELISA for serum samples. The results were compared with other tumor entities, mainly breast. EXPERIMENTAL DESIGN: Samples (563) from patients suffering from primary advanced or metastatic NSCLC were evaluated. RESULTS: HER2 overexpression was demonstrated using IHC in 20% (83 of 410) of the specimens, whereas 2% (7 of 378) were positive by FISH and 6% (31 of 511) showed elevated serum HER2 levels (>15 ng/ml) by ELISA. Sixty-six specimens were positive by IHC only and 13 by ELISA only, whereas none of the specimens was positive only by FISH. Concordance between all of the techniques was seen for only 3 specimens. Of 7 IHC 3+ specimens, 4 showed gene amplification by FISH, and 3 were positive by ELISA (>15 ng/ml), whereas of 76 IHC 2+ cases only 2 were amplified by FISH, and 4 were positive by ELISA. HER2 positivity by at least one of the three techniques was most common in adenocarcinomas, at 29% (42 of 143). CONCLUSION: Gene amplification and HER2 protein overexpression at the 3+ level appear to be uncommon in NSCLC. The concordance between FISH and IHC 3+ disease was good in this study, in addition, ELISA would have detected several patients without IHC/FISH-positive disease. 相似文献