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991.
Tissue cages implanted subcutaneously were used to infect rabbits with erythrogenic toxin (ET) producing streptococci. The in-vivo production of ET was followed during the infection by immunoprecipitation analyses of the tissue cage fluid (TCF). ET types A and C were mainly detected during the first week of infection, but, as late as 4 weeks after the inoculation, ET was occasionally found in TCF. The nonspecific mitogenic activity of ET on human lymphocytes was also used as a biological marker to recognize ET in TCF. Mitogenic activity was detected in 90% of samples during the first week. In order to characterize the mitogenic material released by growing streptococci, TCF was electrofocused in polyacrylamide gel. The eluates of sliced gels were checked for mitogenic activity and compared with a purified ET preparation containing ET types A and C. It could be verified that ET type A was produced under in-vivo conditions by strains NY-5 and SF130, while ET type C was produced by strain T18. Differences between production of toxins in vitro and in vivo might be of significance for the understanding of the pathogenetic mechanisms in streptococcal infection.  相似文献   
992.
Summary Red cell concentrations of hemoglobin (MCHC), H+, Na+, K+, Mg++, Cl were measured in femoral venous blood of six untrained (UT), six endurance trained (TR) and three semitrained (ST) subjects during graded increasing work (4, 8, 12, 18 and 24 mkp/s, 10–15 min on each step) on a bicycle ergometer. Before exercise no significant differences were detected for the measured variables when comparing UT and TR. During exercise MCHC, [Na+], [K+] and [Mg++] remained constant indicating lack of water shift into the erythrocytes in spite of a marked acidosis (lowest pHBlood value 7.225). This lack resulted from an elevated extracellular osmolality. [H+]Ery and [Cl]Ery maximally increased by 2.0×10–8 eq/kg H2O and 10 meq/l, respectively. The change was markedly greater in UT than in TR at equal load. However, if [H+]Ery and [Cl]Ery were related to pH of whole blood, differences between groups almost disappeared and the ions were distributed as predictable from in vitro experiments (Fitzsimmons and Sendroy, 1961). Behaviour of H+ and Cl may be of importance for oxygen dissociation under in vivo conditions.Supported by Bundesinstitut für Sportwissenschaften, Köln  相似文献   
993.
The relationship between the arterial blood pressure and the volume of the arteries within a segment of an extremity is nonlinear. The present paper shows how the flow and volume pulsations of the arteries within a limb segment can be simulated taking this property into account. An electrical model was constructed comprising one resistor and two voltage dependent ‘capacitors’, the latter corresponding to the pressure dependent elasticity, or compliance, of the arteries. Adequate simulations were obtained over a wide pressure range, which is impossible with linear models. The nonlinear, i.e. pressure dependent, relationship between the volume and pressure of arteries, observed under static conditions, must also be taken into consideration when studying pulsatile events with models whether mathematical or physical.  相似文献   
994.
Summary An outbreak of aseptic meningitis in association with ECHO virus type 4 is described. This virus was isolated in 8 out of 12 cases with this syndrome from stool specimens and in two cases also from spinal fluids and furthermore from healthy family contacts. Neutralizing antibodies in the patients sera could not be demonstrated with the conventional tube tests while complement fixing antibodies with increasing titer against ECHO-4 occurred. There is an extensive heterotypic complement fixing antibody response in patients sera within the ECHO virus group between this group and the Coxsackie or the poliomyelitis group as well as beetwen the Coxsackie and the poliomyelitis groups.The choice of tissue for isolation of enteroviruses is discussed. Trypsinized human embryonic kidney seems to provide a suitable medium for this group of viruses.A rubella-like exanthem was seen in about two thirds of the virus positive patients. Some cases had diphasic course.  相似文献   
995.
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   
996.
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   
997.
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   
998.
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   
999.
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.
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   
1000.
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