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951.
Karyotypic evolution in Ph-positive chronic myeloid leukemia in relation to management and disease progression 总被引:1,自引:0,他引:1
Birgitta Swolin Aleksander Weinfeld Jan Westin Johan Waldenström Bengt Magnusson 《Cancer Genetics and Cytogenetics》1985,18(1):65-79
In a prospective study of 32 patients with chronic myeloid leukemia the frequency of chromosome abnormalities in addition to the Philadelphia chromosome (Ph) increased when the disease progressed. Before metamorphosis, 10 patients (31%) had developed additional abnormalities. Such abnormalities were present in three of them at the time of diagnosis; in the other seven, they were detected late in the chronic phase. New clonal abnormalities heralded or accompanied a more malignant phase of the disorder, usually a blastic leukemia. During metamorphosis, 78% of the patients had additional abnormalities, which in 68% of these cases comprised at least one of +8, +22q- or i(17q). Clones with additional abnormalities disappeared in eight cases, either spontaneously or in association with cytostatic therapy during the chronic or blastic phase. Involvement of chromosome #8, usually in the form of a trisomy, was found in 7 of 12 patients treated with busulfan, but was not found in any of the 10 hydroxyurea-treated patients, of whom 8 were splenectomized early during the chronic phase. Cells from the spleen, obtained by fine needle aspiration or splenectomy were cytogenetically examined in 18 cases during the chronic phase, but abnormalities in addition to the Ph were noted in only one patient, who was examined in the late chronic phase. The same abnormalities were present in bone marrow cells of this patient. 相似文献
952.
Frits Ørskov Ida Ørskov Doyle J. Evans Jr. R. Bradley Sack David A. Sack Torkel Wadström 《Medical microbiology and immunology》1976,162(2):73-80
106 enterotoxigenicEscherichia coli strains from children and adults from many parts of the world were serotyped for O and H antigens. Some OH types,i.e. O6H16, O8H9, O15H11, O25H42, O78H11 and O78H12, were found repeatedly from different geographical locations. Some of these OH serotypes were only found rarely among more than 20000E. coli strains collected over many years from different locations and sources. It is suggested that these special OH serotypes represent clones which have been selected to the special conditions in the small intestine and selected to carry the plasmids necessary to provoke diarrhoea. 相似文献
953.
Matthias Wicklmayr Günther Dietze Bernulf Günther Richard Schifmann Ingolf Böttger Reinhard Geiger Hans Fritz Hellmut Mehnert 《Inflammation research》1980,10(4):339-343
The influence of synthetic bradykinin (BK) on disturbed protein and carbohydrate metabolism was studied in chemical and manifest maturity-onset diabetics, in surgical patients and in alloxan diabetic rats. BK,mixed with insulin and injected subcutaneously twice daily in alloxan diabetic rats lowered the morning blood glucose concentration in a dose-dependent way, whereas in a control group treated with insulin only no decrease was seen. Accelerated local blood flow or enhanced vascular permeability as a cause of increased glucose uptake could be ruled out by control experiments using papaverine and eledoisin. Better metabolic control in the BK/insulin-treated group was also indicated by lower arterial levels of free fatty acids and of -hydroxybutyrate, normalized hepatic glycogen content and better growth of body weight. In healthy man an intravenous infusion of BK (80 g/h) did not influence normal fasting blood glucose concentrations, whereas elevated glucose levels in maturity-onset diabetics were continuously reduced within 100 min by 12.2±1.4%. A comparable diabetic group receiving saline alone showed no spontaneous drop of blood glucose concentration. An improvement of pathological carbohydrate metabolism by infusion of BK i.v. could also be demonstrated using the intravenous glucose tolerance test in chemical and manifest maturity-onset diabetics and in surgical patients: in all groupsk values of the glucose tolerance test were significantly increased by BK. This effect was neither due to stimulated insulin release nor to changed glucose pool or to increased renal glucose loss, which was even reduced by BK. Interestingly, normalk values in healthy volunteers were not further improved by BK. A stimulated protein breakdown, which occurs after surgery due to peripheral insulin resistance, can also be restricted by intravenous infusion of BK: in surgical patients urinary nitrogen excretion was reduced by 50% during infusion of BK and was accelerated again after cessation of the infusion. These results indicate that BK can improve the efficacy of exogenous insulin in insulin-deficient animals and depressed insulin sensitivity in maturity-onset diabetics and surgical patients. 相似文献
954.
Arne Burkhardt Ingeborg R. Bos Thomas Löning Jan -Olaf Gebbers Herwart F. Otto Gerhard Seifert 《Virchows Archiv : an international journal of pathology》1979,384(2):223-244
Summary Non-epithelial mesenchymal and neuroectodermal cells occur between the keratinocytes in the stratified squamous epithelium of the oral mucosa. These cells cannot be classified adequately by light microscopy. In the present study the oral mucosa of the lip, cheek and tongue of 50 mice were studied by light and electron microscopy. 3,025 mononuclear interepithelial cells were documented and analysed.Monocytogenic macrophages, plasma cells and mast cells were not found interepithelially and cannot be regarded as a regular constituent of the epithelium. Only a few neuroectodermal cells — in mice these are exclusively Merkel cells, with no melanocytes — were localized in the epithelium. The majority of the interepithelial cell population is made up of lymphocytes (22.8%) and Langerhans cells (56.8%). They are an integral constituent of the epithelium. Lymphocytes with rounded and indented nuclei can be identified. The larger and dendritic Langerhans cells are a specific cell of squamous epithelium and also occur in the oral mucosa. Not all cells which feature the cytological characteristics of Langerhans cells contain Langerhans or Birbeck granules. Accordingly these granules cannot be considered an exclusive identification characteristic. Two types of Langerhans cells can be differentiated. 80.9% have the more or less typical appearance known from the epidermis and were termed macrophagocytoid Langerhans cells. The nuclei are irregularly indented and moderately heterochromatic. 19.1% possessed conspicuous large, spherical, euchromatic nuclei and an electron-lucent cytoplasm. These were termed reticuloid Langerhans cells. About 20% of the interepithelial cell population could not be identified, neither as typical lymphocytes nor as Langerhans cells. These were small to medium sized cells with deeply indented cerebriform strongly heterochromatic nuclei. They are similar to the Sézary cells or mycosis fungoides cells of epidermotropic human T-cell lymphomas. The lymphocytic nature of these cells has been confirmed. It seems likely that differentiation of lymphocytes to cerebriform cells occurs within the epithelium. It is further discussed whether cerebriform cells are precursors of Langerhans cells, a conclusion suggested morphologically by transitional forms. This would imply that Langerhans cells originate from lymphocytes, and that the cerebriform cell is an intermediate step of differentiation. The microenvironment of the squamous epithelium may play a role in the process of differentiation, which could explain the epitheliotropy of lymphocytes. The possibility is considered that Langerhans cells and interdigitating reticulum cells of the T-cell area of lymph nodes are identical. The close functional cooperation of Langerhans cells, lymphocytes, and interdigitating reticulum cells in immunological defenses against external antigens is discussed.The authors wish to express their sincere appreciation to Miss P. Starck and Miss I. Brandt for invaluable technical assistance in this project. 相似文献
955.
W. Schröter E. Schulz R. Bonn 《Journal of molecular medicine (Berlin, Germany)》1970,48(16):1013-1014
Zusammenfassung Bei 16 von 17 Patienten mit Osteomyelofibrose wurden in den Erythrocyten erhöhte Konzentrationen an reduziertem Glutathion nachgewiesen. Die Bestimmung des Glutathions kann als differentialdiagnostisch wertvolles Kriterium für die Charakterisierung der Osteomyelofibrose angesehen werden.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
Summary In 16 of 17 patients with osteomyelofibrosis the concentration of erythrocyte reduced glutathione was increased. It is concluded that the determination of erythrocyte glutathione is of differential diagnostic value in the characterization of osteomyelofibrosis.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
956.
Decrease and gain of gene expression are equally discriminatory markers for prostate carcinoma: a gene expression analysis on total and microdissected prostate tissue 总被引:8,自引:0,他引:8 下载免费PDF全文
957.
958.
Incidence of chromosomal imbalances in advanced colorectal carcinomas and their metastases 总被引:6,自引:0,他引:6
Knösel T Petersen S Schwabe H Schlüns K Stein U Schlag PM Dietel M Petersen I 《Virchows Archiv : an international journal of pathology》2002,440(2):187-194
Comparative genomic hybridization (CGH) was used to screen 54 advanced colon carcinomas. i.e., 24 primary tumors and 30 metastases, for chromosomal alterations. Using a sensitive statistical method for the determination of DNA imbalances and histograms for analysis of the incidence of changes, we identified the DNA over-representation of chromosome 20q as the most common alteration being present in 100% of cases. High incidence deletions were observed on 18q21-18q23 (96%), 4q27-4q28 (96%), 4p14 (87%), 5q21 (81%), 1p21-1p22 (72%), 21q21 (74%), 6q16 (72%), 3p12 (66%), 8p24-8p21 (66%), 9p21 (64%), 11q22 (64%), and 14q13-14q21 (64%). Further frequent over-representation was found on 7q12-7q11.2 (75%), 16p11-16p12 (70%), 19p13 (70%), 9q34 (67%), 19q13 (67%), 13q34 (64%), 13q13 (64%), 17q21 (59%), 22q11 (61%), 8q24 (57%), and 1q21 (57%). Pronounced DNA gains and losses being defined as regions in which the ratio profiles exceeded the values of 1.5 and 0.5, respectively, frequently colocalized with peaks of incidence curve. The use of difference histograms for the comparison of tumor subgroups as well as case-by-case histogram for the analysis of 15 paired tumor samples identified several of the above alterations as relevant for tumor progression and metastasis formation. The study identified additional loci and delineates more precisely those that have been previously reported. For comparative purposes, we have made our primary data (ratio profiles, clinicopathological parameters, histograms) available at the interactive web site http://amba.charite.de/cgh, where the incidence of changes can be determined at individual loci and additional parameters can be applied for the analysis of our CGH results. 相似文献
959.
Peter Gross Will W. Minuth Markus Ketteler Eberhard Frömter Rita Böhm 《Pflügers Archiv : European journal of physiology》1988,412(4):434-441
The ionic conductive properties were studied of epithelia of collecting duct principal cells which had been grown in primary tissue culture from renal cortex/capsule explants. When pretreated with aldosterone (10–6 mol/l) and bathed on either surface with isotonic HCO
3
–
-free Ringer's solution, the transepithelial voltage,V
te, varied between –21 and –72 mV (apical surface negative) while the transepithelial resistance,R
te, ranged from 0.4 to 1.5 kcm2. By 10:1 step-changes in Na+ concentration the apical cell membrane was shown to have a high conductivity for sodium, inhibitable by amiloride, 10–6 mol/l. However, contrary to observations in natural collecting duct under control conditions, amiloride never reversed the polarity ofV
te even at 10–4 mol/l. Both the apical and the basolateral cell membranes were conductive for potassium and both conductivities were inhibitable by Ba2+ (5 mmol/l). 10:1 reduction of apical Cl– concentration strongly hyperpolarizedV
te with a monophasic time course suggesting the presence of a paracellular shunt conductance for Cl–. In addition there may be a small Cl– conductance present in the apical cell membrane since apical application of the chloride channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPAB) at 10–7 mol/l produced a minute but significant hyperpolarization. On the other hand, 10:1 reduction of basolateral Cl– concentration caused a biphasic change inV
te (initial depolarization, followed by repolarization) which indicates the presence of a large Cl– conductance in the basolateral cell membrane. The latter was not inhibitable by 10–7 mol/l NPPAB. Higher concentrations of this and of an other Cl– channel blocker produced non-specific effects. In conclusion, our studies of a pure principal cell epithelium confirm findings described for the intact cortical collecting duct and add new information concerning chloride conductivity and related blocking agents.Dedicated to Prof. Dr. H. Sitte, Homburg, FRG, upon his 60th birthday. 相似文献
960.
H. Schön W. Zeller N. Henning 《Journal of molecular medicine (Berlin, Germany)》1963,41(22):1108-1109
Zusammenfassung Es wird über erste Ergebnisse einer Therapie der Hyperlipoproteidämie mit einer Retardpräparation des ß-Pyridyl-carbinol (Ronicol retard®) berichtet. Neben einer ausgeprägten Senkung der Gesamtesterfettsäuren und des Cholesterins im Serum wurde ein Rückgang der Leberepithelverfettung erreicht. Als Wirkungsmechanismus wird neben der bekannten Hemmung der Acylierung durch Nicotinsäure eine Hemmung der Fettmobilisierung (Hemmung einer adrenalinsensiblen Fettgewebslipase) diskutiert.Versuchspräparat der Firma Hoffman-La Roche AG; inzwischen als Ronicol-retard im Handel. 相似文献