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91.
Mouse keratinocyte stem cells originate from the bulge of hair follicle, and, according to definition, possess a clonogenic activity in vitro. We have investigated seven inbred (C57BL/6, C3H, DBA/2, BALB/c, FVB) and outbred (SENCAR, CD-1) mouse strains and found that three genetically distinct subsets of mouse strains differ significantly in the frequency of clonogenic activity in vitro. The analysis of keratinocyte colonies in two reciprocal backcross [C57BL/6 x (BALB/c x C57BL/6); BALB/c x (BALB/c x C57BL/6)] and intercross [(BALB/c x C57BL/ 6)F2] of BALB/c and C57BL/6 mice allowed us to identify two subpopulations of clonogenic keratinocytes able to produce small (less than 2 mm2) and large (more than 2 mm2) colonies. We conducted linkage analysis and found that small colonies associated with mouse chromosomes 1, 6, 7, 8, and 9; but large colonies--with the chromosome 4. We defined locus on the chromosome 9 that associated with small colonies as keratinocyte stem cell locus 1 (Ksc1), and locus on the mouse chromosome 4 associated with large colonies-keratinocyte stem cell locus 2 (Ksc2). Ksc1 and loci on chromosomes 6 and 7 are close if not equal to loci associated with sensitivity to skin carcinogenesis. We conclude that two subpopulations of stem cells able to produce small and large colonies regulated by different genes and genes regulating small colonies might be responsible for sensitivity to skin carcinogenesis.  相似文献   
92.
Repeated administration of the anxiolytic tofisopam (grandaxin) reduced anxiety and improved both visual and verbal short-term memory in young male and female humans. The expression of these effects depends on the daytime (morning versus evening) and on the sex of volunteers. Valerian extract did not produce significant effect on the anxiety states and short-time memory.  相似文献   
93.
Morphofunctional immune disorders were revealed in vasopressin-deficient Brattleboro rats with diabetes insipidus during ontogeny. We observed a permanent decrease in the number of blood lymphocytes, increase in neutrophil count, reduced activity of macrophages, early involution of the thymus and spleen, and suppression of antibody production. These changes reflect impaired general resistance of these animals.  相似文献   
94.
BACKGROUND: Lung fibroblasts may have a pivotal role in airway inflammation as they are involved in continuous cycles of mediator secretion, proliferation, activation and cross-talk with recruited inflammatory cells. The role of fibroblasts as intermediate participants in the inflammatory network suggests that they could represent an important target for drugs commonly used in asthma; thus, we investigated the effects of triamcinolone acetonide (TAA) on primary human lung fibroblasts. METHODS: The in vitro activity of increasing concentrations (10(-9) to 10(-7) M) of TAA in fibroblast cultures was evaluated as regards the following parameters: proliferation, extracellular matrix (ECM) release, cytokine/chemokine secretion and surface antigen expression. RESULTS: All concentrations of TAA decreased fetal calf serum (FCS)-induced fibroblast proliferation, whereas in the presence of FCS plus basic fibroblast growth factor TAA was only effective at 10(-8) and 10(-7) M. TAA failed to decrease ECM, whereas at 10(-8) and 10(-7) M it decreased IL-6 and IL-8 secretion to different extents. In the presence of IFN-gamma the drug was able to reduce VCAM-1 expression at all of the tested concentrations; on the other hand, in TGF-beta 1-driven cultures a decrease in CD54 expression was detected with TAA at 10(-8) and 10(-7) M. CONCLUSIONS: TAA acts on some functional properties of human lung fibroblasts that make these cells active participants in the inflammatory network. The ability of TAA to inhibit lung fibroblast proliferation may prevent or even reverse some of the histological changes that characterize airway remodeling in chronic inflammatory diseases; moreover, IL-6, IL-8 and surface molecule decreases by TAA may suggest a direct anti-inflammatory effect of the drug by suppression of resident lung cell function.  相似文献   
95.
96.
Electrophysiological mechanisms of the action of cardiocyclide, nibentan, and sotalol--antiarrhythmic agents of class III--was studied in dogs with experimental myocardial infarction induced by a two-step occlusion of the coronary artery. Cardiocyclide exhibited the properties typical of the class III antiarrhythmics by prolonging the ventricular repolarization and increasing the effective refractory periods in the atrium and ventricles. The degree of manifestation of these antiarrhythmic effects of cardiocyclide is independent of the induced heart rate, which is related to the ability of this drug to block the slow activation component (IKs) of the delayed rectified potassium current. Nibentan elongates the QT interval and increases the effective atrial and ventricular refractory periods, but the effect was dependent of the stimulation frequency. Sotalol, which also exhibited the properties of a class III antiarrhythmogen possessing beta-blocking activity, produced more pronounced inhibiting action upon the sinus node function and conduction (in comparison with the analogous effects of cardiocyclide). This is probably related to the ability of sotalol to block the cardiac adrenoreceptors. The effect of sotalol is also frequency-dependent, which is related to the blocking of rapid activating component (IKr) of) of the delayed rectified potassium current. On the background of isoproterenol infusion, cardiocyclide completely retained the electrophysiological and antiarrhythmic effects. The efficacy of nibentan and sotalol with respect to the repolarization and refractoriness significantly decrease under the conditions of sympathetic nervous system activation. The ability of sotalol to suppress the sinus node function and conduction on the background of isoproterenol infusion is retained.  相似文献   
97.
98.

Background  

Low grade fibromyxoid sarcomas (LGFMS) are very rarely seen. They commonly arise from deep soft tissues of the lower extremities. Very few cases of intra-abdominal location have been reported.  相似文献   
99.
The trial enrolled 38 patients with chronic HCV-infection and Sjogren's syndrome (mean age 44.3 +/- 13.7 years). Biopsy of the minor salivary glands (MSG) was made in 20 patients. Polymerase chain reaction was used to study 20 MSG biopsies, 38 samples of native saliva for HCV-RNA. Saliva samples were also studied for Herpes virus DNA (EBV, CMV, HHV-VI type). All the patients with VHC appeared to have signs of xerostomia, 24 (63.2%) patients had xerophthalmia. MSG pathohistological changes were found in 19 (95%) patients. In the majority of cases (86.9%) they were characterized by mild infiltration and advanced fibrosis. HCV-RNA was found in the saliva of 23 (57.5%) patients, in MSG tissue--in 9 (39.1%) patients. HCV-RNA detection in the saliva did not depend on the degree of viremia, viral RNA in MSG correlated with viral load. EBV and HHV-VI, HHV-VI only and EBV were detected only in 7 (18.4%), 10 (26.3%) and 6 (15.8%) patients, respectively. Xerostomia occurred with the same rate (26.1 and 31.3%) in patients with and without herpes viruses in the saliva. Detection rate for HCV-RNA in the saliva was not related with viremia degree. Sjogren's disease symptoms in CHC patients did not depend on the presence or absence of DNA of herpes viruses in the saliva.  相似文献   
100.
AIM: To study the time of nuclear magnetic resonance (NMR) of spin-lattice serum relaxation (T1) in the dynamics of an infectious process in patients with different forms of erysipelas. MATERIALS AND METHODS: 37 patients with different clinical forms of erysipelas were examined in the acute period of the disease and in the early period of convalescence. RESULTS: A statistically significant increase in T1 NMR was ascertained in patients with bullous hemorrhagic erysipelas as compared with those with erythematous form. CONCLUSION: Pronounced changes in the functional status of serum in patients with hemorrhagic forms of erysipelas are of great importance in the development of the local hemorrhagic syndrome.  相似文献   
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