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21.
目的 探讨舒喘灵气雾剂对毛细支气管炎的治疗效果。方法 选择106例住院毛细支气管炎患儿随机分为两组,对照组给予常规治疗,治疗组在常规治疗的基础上给予舒喘灵气雾剂,每天3次吸入。疗程结束后,观察毛细支气管炎改善情况。结果 治疗组有效率90%,对照组有效率17.4%,两组对比P<0.01,差异显著。结论 舒喘灵气雾剂对毛细支气管炎治疗效果佳,副作用小,值得推广。  相似文献   
22.
冒青  陆韦  潘焕  杨平  何英 《遵义医学院学报》2002,25(4):329-329,331
目的 评价莪术油治疗毛细支气管炎的疗效。方法 毛细支气管炎患儿 110例 ,随机分为治疗组 6 0例和对照组 5 0例 ,6d为 1疗程 ,比较两组治愈率 ,临床指标对比观察 (咳喘 ,肺部罗音消失时间 ,住院时间 )。结果 总治愈率治疗组 96 .7% ,对照组 80 % ,两组比较有显著性差异 (P <0 .0 5 )。结论 莪术油治疗毛细支气管炎疗效满意。  相似文献   
23.
Objective: Effective material exchange between blood and tissue depends on the heterogeneity of microvascular flow. The objective was to address inconsistencies between intravital studies regarding this dependency. We tested the hypothesis that heterogeneity of red blood cell velocity (VRBC) in capillary beds varies with the strength of metabolic stimulus and with capillary bed geometry. Methods: We used videomicroscopy to measure VRBC in a bed of 10–24 capillaries at the surface of extensor digitorum longus (EDL) muscle in anesthetized rats. The coefficient of variation (CV = standard deviation/mean; an index of spatial heterogeneity) was computed in the same bed before and after (i) 1, 2, 4, or 8 Hz supramaximal muscle contraction or (ii) adenosine superfusion (10?7–10?3 M). Beds with or without arteriolar—venular capillary shunts were used. Results: Although control VRBC differed between beds (shunt: 232 μm/s; no shunt: 130 μm/s), the percentage increases in postcontraction VRBC did not (range: 111–326%). In both beds, control CV varied greatly (overall range: 28–117%) and 2–8 Hz muscle contractions reduced CV significantly by 25%. Similar results were obtained for adenosine. In confirmatory experiments using the rat cremaster muscle, contractions (4 Hz) and adenosine (10?4 M) also reduced CV. Based on all data, CV = 63–0.022 VRBC (r = 0.82, P < 0.001). Conclusions: The heterogeneity of VRBC decreased with metabolic stress, regardless of capillary bed geometry. We propose that both the large variability in control CV and the relatively shallow dependence of CV on velocity could be responsible for the present inconsistencies between intravital studies.  相似文献   
24.
Summary Muscle force recovery from short term intense exercise was examined in 16 physically active men. They performed 50 consecutive maximal voluntary knee extensions. Following a 40-s rest period five additional maximal contractions were executed. The decrease in torque during the 50 contractions and the peak torque during the five contractions relative to initial torque were used as indices for fatigue and recovery, respectively. Venous blood samples were collected repeatedly up to 8 min post exercise for subsequent lactate analyses. Muscle biopsies were obtained from m. vastus lateralis and analysed for fiber type composition, fiber area, and capillary density. Peak torque decreased 67 (range 47–82%) as a result of the repeated contractions. Following recovery, peak torque averaged 70 (47–86%) of the initial value. Lactate concentration after the 50 contractions was 2.9±1.3 mmol·l−1 and the peak post exercise value averaged 8.7±2.1 mmol·l−1. Fatigue and recovery respectively were correlated with capillary density (r=−0.71 and 0.69) but not with fiber type distribution. A relationship was demonstrated between capillary density and post exercise/peak post exercise blood lactate concentration (r=0.64). Based on the present findings it is suggested that lactate elimination from the exercising muscle is partly dependent upon the capillary supply and subsequently influences the rate of muscle force recovery. Dr. Tesch was on leave from Department of Clinical Physiology, Karolinska Hospital, Stockholm, Sweden  相似文献   
25.
Background: The presence of efferent fibers in the anteromedial eye of liphistiid spiders kept in natural daily cycles of illuminance has been reported. However, this report is limited to innervation by the efferent fiber and daily rhabdomal changes, and there have been no detailed ultrastructural accounts of the eye. Methods: The fine structure of this eye was examined by electron microscopy. Results and conclusions: The eye consists of a cornea, a lens, a vitreous body, and a retina. The retina contains 13 or 14 receptor cells and glial cells. The rhabdoms are distal to the nuclei of the receptor cells. In the distal region of the receptive segment, the rhabdomeres lie in the center of the cell. In the middle region, anisomorphic rhabdoms formed by microvilli from adjacent cells are at the cell periphery. In the proximal region, the rhabdomeres are situated in the center of the cell. The ocellar nerve of the eye runs toward the protocerebrum and enters the posterior part of the first optic ganglion of the secondary eyes. Pigmented cells and nonpigmented cells are observed. The pigmented cells are located in the most lateral of the eye and cover the whole eye. The nonpigmented cells are located in the receptor cell bodies and extend to the origin of the ocellar nerve. They wind to form capillaries filled with electron-dense material. These structures are discussed in comparison with those of other spiders and other chelicerates. © 1994 Wiley-Liss, Inc.  相似文献   
26.
For highly diffusive solutes the kinetics of blood–tissue exchange is only poorly represented by a model consisting of sets of independent parallel capillary–tissue units. We constructed a more realistic multicapillary network model conforming statistically to morphometric data. Flows through the tortuous paths in the network were calculated based on constant resistance per unit length throughout the network and the resulting advective intracapillary velocity field was used as a framework for describing the extravascular diffusion of a substance for which there is no barrier or permeability limitation. Simulated impulse responses from the system, analogous to tracer water outflow dilution curves, showed flow-limited behavior over a range of flows from about 2 to 5 ml min–1 g–1, as is observed for water in the heart in vivo. The present model serves as a reference standard against which to evaluate computationally simpler, less physically realistic models. The simulated outflow curves from the network model, like experimental water curves, were matched to outflow curves from the commonly used axially distributed models only by setting the capillary wall permeability–surface area (PS) to a value so artifactually low that it is incompatible with the experimental observations that transport is flow limited. However, simple axially distributed models with appropriately high PSs will fit water outflow dilution curves if axial diffusion coefficients are set at high enough values to account for enhanced dispersion due to the complex geometry of the capillary network. Without incorporating this enhanced dispersion, when applied to experimental curves over a range of flows, the simpler models give a false inference that there is recruitment of capillary surface area with increasing flow. Thus distributed models must account for diffusional as well as permeation processes to provide physiologically appropriate parameter estimates. © 2000 Biomedical Engineering Society. PAC00: 8719-j, 8710+e  相似文献   
27.
Summary A female patient is described in whom the diagnosis of idiopathic hypereosinophilic syndrome (HES) with heart disease and peripheral neuropathy was made at the age of 32 years. Although prednisone induced a prompt and longstanding complete hematological remission, progressive and eventually intractable heart failure developed, and the patient died 6 years later. Endomyocardial biopsy at diagnosis showed infiltration with intact and disintegrated eosinophils and Charcot-Leyden crystals. Echocardiographic follow-up (including Doppler-Echocardiography) revealed mitral regurgitation with thickening and impaired motility of the posterior mitral leaflet, as well as progressive dilated cardiomyopathy. At autopsy, a diffuse interstitial fibrosis with patchy prominence in an eccentric hypertrophic and highly dilated heart was found. There were no significant endocardial thickening and no mural thrombi. In contrast to the findings of the initial endomyocardial biopsy, autopsy revealed no eosinophilic infiltrate.In this case, eosinophil-induced heart disease manifested as dilated cardiomyopathy, without endocardial fibrosis as originally described by Löffler. We speculate, that eosinophils have been deposited predominantly in the myocard at an early stage of disease, and — activated locally — secreted their granule proteins producing an initial damage to capillary endothelial cells and myocytes. After prednisone-induced clearance of eosinophils from blood and tissues, progressive, self-perpetuating interstitial fibrosis of the myocard and loss of myocytes eventually resulted in end-stage dilated cardiomyopathy.Abkürzungsverzeichnis HES idiopathic hypereosinophilic syndrome - UBBC unsaturated vitamin B12 binding capacity - ECP eosinophil cationic protein - MBC major basic protein - EDD end-diastolic diameter of the left ventricle - LA left atrium diameter - LVEDP left ventricular end-diastolic pressure - NIH National Institutes of Health  相似文献   
28.
Summary Simultaneous right heart catheterization and radionuclide ventriculography were performed in 27 patients with a wide range of chronic obstructive pulmonary disease. Central hemodynamics and radionuclide studies were done at rest and during exercise. In the resting state the right ventricular ejection fraction (RVEF) was in the normal range (43.3±6%). During exercise a significant (p<0.001) decrease of RVEF to 38.8±6.7% occurred. The pumonary artery mean pressures were 19.9±3.8 at rest. During exercise a significant (p<0.001) increase to 41±9.8 mm Hg occurred. There was a linear relationship between pulmonary pressures and RVEF during exercise in patients with pulmonary artery pressures not exceeding 35 mm Hg. In patients with right ventricular end-diastolic wall thickness 6 mm a curvilinear relationship between these parameters could be observed with a flattening of the curve at higher pressures (>35 mm Hg) and lower ejection fractions (<35% RVEF). Radionuclide venticulography cannot substitute for right heart catheterization. Echocardiography is useful for interpretation of right ventricular ejection fractions in advanced chronic obstructive pulmonary disease.Abbreviations CI Cardiac index (l/min/m2) - CO Cardiac output (l/min) - COPD Chronic obstructive pulmonary disease - FEV1 Forced expiratory volume in the first second (ml) - HR Heart rate (B/min) - PAd Pulmonary artery diastolic pressure (mm Hg) - PAP Pulmonary artery mean pressure (mm Hg) - PAs Pulmonary artery peak pressure (mm Hg) - PVR Pulmonary vascular resistance (dyn·s·cm–5) - PwP Pulmonary capillary wedge pressure (mm Hg) - RAP Right arterial pressure (mm Hg) - Raw Airway resistance (cm H2/l/s) - RNV Radionuclide ventriculogram - RV Residual volume (l) - RVEF Right ventricular ejection fraction (%) - RVEDVI Right ventricular enddiastolic volume index (ml/m2) - RVEDVI SVI RVEF (ml/m2) - RVESVI Right ventricular endsystolic index (m2/m2) - SVI Stroke volume index (ml/m2) - TLC Total lung capacity (l) - VC Vital capacity (l)  相似文献   
29.
Summary Muscle fiber type composition and capillary supply in rat diaphragm were investigated after 14 weeks of endurance training: body weight and muscle fiber area were significantly decreased, the muscle fiber type composition, capillary to fiber ratio and number of capillaries around each fiber type were unchanged, and the capillary density and number of capillaries around each fiber relative to fiber type areas were significantly increased. These small fiber areas and increased capillary supplies in the trained rats would facilitate oxygen transport to all parts of the muscle fiber during exercise. It is concluded that the changes observed in the trained rat diaphragm appear to enhance the capacity for oxidative metabolism.  相似文献   
30.
舌粘膜及粘膜下血管网的构筑及其临床意义   总被引:5,自引:0,他引:5  
本研究应用手术显微镜和扫描电镜观察了人舌粘膜的微血管构筑。舌深动脉长支和舌背动脉终支在舌粘膜下形成一完整的致密动脉网,跨越界沟和舌正中线,成为一整体。由动脉网发出微动脉支进入舌粘膜内,形成粘膜内的毛细血管网和各种乳头毛细血管丛。另外,还讨论了舌粘膜下馓血管构筑和舌瓣设计与临床舌诊的关系。  相似文献   
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