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31.
Zusammenfassung Es wird über Versuche berichtet, in denen bei freier und artefiziell behinderter Ausatmung Beziehungen zwischen Atemzeitvolumen und alveolärem CO2-Druck aufgestellt wurden. Unter Stenoseatmung werden für gleiche Änderungen des Atemzeitvolumens größere Differenzen des alveolären CO2-Druckes benötigt. Die Verschiebungen werden als Folge der bei erschwerter Atmung erhöhten Atemarbeit gedeutet und nicht auf eine Änderung der Erregbarkeit des Atemzentrums zurückgeführt. Die alveoläre Hypoventilation bei obstruktiven Ventilationsstörungen kann daher — so wird weiter gefolgert — ihren Ursprung in der vermehrten Atemarbeit haben, ohne daß zwingend eine andere pathogenetisch wirksame Ursache diskutiert werden muß. Auf die Bedeutung von Veränderungen des Atemwiderstandes bei der experimentellen Prüfung atemwirksamer Pharmaka wird hingewiesen.Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
32.
The content of dissolved oxygen was determined by four independent methods in a series of non-aqueous or heterogenous systems. The Lex-O2-Content Analyzer represents a fast and simple apparatus that employs a coulometric oxygen assay with Hersch cell detection. A comparison of the results with different methods demonstrates the reliability of the Lex-O2 in the determination of oxygen dissolved in heterogeneous or non-aqueous systems. Therefore, this apparatus can be recommended for the measurement of oxygen in oxygenator or perfusion fluids, as well as in blood substitutes or other oxygen transporting systems.  相似文献   
33.
Between 1983 and 1993, 41 patients underwent a first-stage Belt-Fuqua operation for penile hypospadias repair and 39 completed the second stage. Minor complications were observed after the first stage. The primary success rate following the second stage was 82%. Major complications noted after the second stage consisted mainly of fistula formation. The surgical technique is described and alternative methods are discussed.  相似文献   
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35.
BACKGROUND: The main manifestations of GAPO syndrome are growth retardation (G), alopecia (A), pseudoanodontia (P), and optic atrophy (O). CASES: This syndrome has been described in 21 patients from 16 different families. Four cases are from Turkey and have been presented by Sayli and Gül. The purpose of our study is to document the cases from Turkey and discuss the ophthalmological and neuro-ophthalmolgical findings of these and other reported GAPO cases. OBSERVATIONS: All patients in the literature and our 4 cases have severe growth retardation with delayed bone age in infancy, characteristic facial appearance (high and bossed forehead, midface hypoplasia), alopecia or severe hypotrichosis, and pseudoanodontia. Optic atrophy was present in 1 of our cases and in 5 previous cases. Glaucoma was present in 5 cases, including 2 of ours. Buphthalmia and keratopathy secondary to glaucoma were also observed. White eyelashes, seen only in our cases, may be a sign of "early senility." CONCLUSIONS: Optic atrophy is not a constant finding in GAPO syndrome. Glaucoma may accompany the ocular findings. This syndrome has been attributed to either ectodermal dysplasia or the accumulation of extracellular connective tissue matrix, due to an enzyme deficiency involved in its metabolism. Current studies show that an elastin defect and secondary changes in collagen may be important in the pathogenesis of the disease.  相似文献   
36.
F Oztürk  E Kurt  U U Inan  L Emiro?lu  S S Ilker 《Cornea》1999,18(4):466-471
PURPOSE: To investigate the effects of topical acetylcholine and topical administration of propolis, a natural beehive product, on corneal epithelial wound healing. METHODS: The whole corneal epithelium was debrided in 42 eyes of 21 rats by mechanical scraping with a dulled scalpel blade. Animals were divided into three groups. Group 1 received topical 1% water extract of propolis (WEP), group 2 received topical acetylcholine (ACh), and group 3 (control group) received topical phosphate-buffered saline, 6 times a day for 3 days, starting immediately after debridement. The area of the corneal epithelial defect was stained with fluorescein, photographed, and then measured every 12 h. The mean epithelial defect area and the mean percentage of epithelial defect remaining at each follow-up were compared between the groups. RESULTS: The mean epithelial defect area and the mean percentage of epithelial defect remaining at each time were significantly smaller (p < 0.001, p < 0.05, respectively) in the ACh and propolis groups as compared with control groups. There was no statistically significant difference between the propolis or ACh groups at any time (p > 0.05). At 72 h, the mean percentage of defect remaining was 2.58% in the ACh group, 1.3% in the propolis-treated group, and 8.68% in the control group. CONCLUSIONS: This study demonstrated that ACh and propolis facilitated corneal epithelial wound healing of rats. Although the mechanisms of the effect of propolis on wound healing and its clinical use still remain to be determined, ACh may have a place in the treatment of corneal epithelial injuries.  相似文献   
37.
Purpose. A QSAR study based on electrotopological state (E-state) indices was conducted for a series of flavone HIV-1 integrase inhibitors to guide drug design. Methods. E-state indices formulated to encode electronic and topological information for each skeletal atom in a molecule (Kier and Hall Pharm. Res. 7:801–807 (1990)) were calculated using the Molconn-X program, and partial least squares (PLS) multivariate regression was used to derive QSAR models. Results. Predictive models with correlation coefficients (r2) of 0.98 (3 PLS components) and 0.99 (5 PLS components) and corresponding cross-validated correlation coefficients (c.v. r2) of 0.51 and 0.73, were obtained for inhibition of cleavage and integration, respectively, with one molecule omitted from the analysis. Conclusions. E-state indices at C6, C3, C5, C5, and O4 were found to be more important for prediction of activity than those for any of the other 12 flavone skeletal atoms that are common to the molecules in the data set.  相似文献   
38.
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   
39.
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   
40.
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   
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