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71.
Objectives The aims of the study were to assess the correlation between the plasma concentration of ophthalmic timolol and cardiovascular parameters, and the influence of timolol on advanced haemodynamic variables, such as stroke (SI), cardiac (CI) and systemic vascular resistance (SVRI) indices and arterial pulse wave velocity (PWV).Methods Twenty-five glaucoma or ocular hypertensive patients were treated with 0.5% aqueous and 0.1% hydrogel formulations of timolol using a randomised, double-masked, crossover, multicentre design. All the patients were subjected to passive head-up tilt, electrocardiography, exercise test and measurement of plasma concentration of timolol. In the analysis, the data on the two treatments were combined, and the Spearman correlation coefficients between the plasma level of timolol and physiological effects were calculated.Results During the head-up tilt test before rising the bed up, the resting heart rate (HR; R=–0.52, P=0.001) and PWV (R=–0.34, P=0.04) were inversely correlated with timolol level. In the upright position, ophthalmic timolol effectively suppressed the rise in HR (R=–0.36, P=0.03). The SI did not change with timolol concentration, while CI diminished as timolol concentration rose (R=–0.39, P=0.02). The SVRI correlated with timolol concentration (R=0.38, P=0.02). In the exercise test, correlation between HR and plasma level of timolol steadily grew stronger as the load increased, reaching R=–0.60 (P<0.0001) at the maximum load. Systolic and diastolic arterial pressures were not associated with the timolol concentration.Conclusion The plasma concentration of ophthalmic timolol correlates with several haemodynamic effects. As HR decreases, SVRI increases and blood pressure is kept unchanged.  相似文献   
72.

Background

BCG vaccine is considered to have immunoprophylactic potential in leprosy. However controversy exists about the extent of prophylaxis it provides. In view of this, a study was undertaken to see the evolution of disease in established cases of leprosy who were already vaccinated with BCG and to compare it with the cases of leprosy who were not vaccinated with BCG.

Methods

114 newly diagnosed cases of leprosy were studied. Patients were divided into two groups-BCG vaccinated and non-vaccinated. Clinical diagnosis of leprosy was confirmed by bacteriological and histopathological studies in each case. All patients were given standard anti leprosy treatment and were evaluated monthly for a minimum period of one year.

Results

All the cases were males in the age group of 20 to 50 years. 25.4% of cases had received BCG vaccine and 74.6% were not vaccinated for the same. No significant difference was observed in the incidence of different types of leprosy in vaccinated and non-vaccinated groups. 25.9% cases in non-vaccinated group developed lepra reaction as compared to 13.8% in vaccinated group. The incidence of deformities and disabilities in vaccinated group was only 10.3% as against 18.8% in non-vaccinated group. The rate of bacillary clearance appeared faster in vaccinated group.

Conclusions

Although there is no significant difference in the pattern of different types of leprosy in BCG vaccinated and non-vaccinated cases, there is reduction in the incidence of reactions as well as deformities and disabilities in BCG vaccinated cases as compared to non-vaccinated cases.Key Words: BCG Vaccine, Leprosy  相似文献   
73.
Uusitalo H  Rantakokko J  Vuorio E  Aro HT 《BONE》2005,36(1):142-149
The present study was carried out to determine whether immobilization-induced (Im) osteopenic bone possesses the same reparative capacity as normal healthy bone. Furthermore, the effects of mechanical loading versus immobilization on bone defect healing were studied. Three-week cast-immobilization was used to induce local osteopenia in mice. A standardized metaphyseal bone defect of the distal femur was created unilaterally both in immobilization-induced (Im) osteopenic mice and in nonimmobilized (Mo) age-matched control animals. After creation of the bone defect, the animals in both groups were further divided into two groups: 3-week cast-immobilization (Im-Im and Mo-Im) groups, and unrestricted weight-bearing (Im-Mo and Mo-Mo) groups. The healing process was followed up to 3 weeks using RNA analysis, histomorphometry, biomechanical testing, and pQCT measurements. At 3 weeks of healing without immobilization, bone mineral density (BMD), as well as bone bending stiffness and strength were higher in normal (Mo-Mo) than in osteopenic (Im-Mo) bone. Although the levels of mRNAs characteristic to chondrocytes (Sox9 and type II collagen), hypertrophic chondrocytes (Type X collagen), osteoblasts (type I collagen and osteocalcin), and osteoclasts (cathepsin K) during the bone defect healing exhibited similarities in their expression profiles, mechanical loading conditions also caused characteristic differences. Mechanical loading during healing (Mo-Mo group) induced stronger expression of cartilage- and bone-specific genes and resulted in higher BMD than that seen in the cast-immobilized group (Mo-Im). In biomechanical analysis, increased bending stiffness and strength were also observed in animals that were allowed weight-bearing during healing. Thus, our study shows that bone healing follows the same molecular pathway both in osteopenic and normal bones and presents evidence for reduced or delayed regeneration of noncritical size defects in immobilization-induced osteopenic bone.  相似文献   
74.
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
75.
Computed tomographic appearance of the bulging annulus   总被引:6,自引:0,他引:6  
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76.
Differential CT diagnosis of extruded nucleus pulposus   总被引:1,自引:0,他引:1  
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77.
OBJECTIVES: To give an overview of telemedical applications in ophthalmology and to provide background information on new tele-ophthalmological applications. METHODS: We carried out a literature review, a database search and an Internet search. RESULTS: According to published research, the cost-efficiency of telemedicine in ophthalmology has not been established. It has been found to have educational benefits and patients have been satisfied with the possibility of obtaining specialist care without having to travel. CONCLUSIONS: Most studies have been pilot studies and telemedicine is still seldom the primary mode of operation. Technical problems have not been significant, but many open questions about organizational and operational issues remain. Further studies should be directed towards solving these problems and establishing technical standards.  相似文献   
78.
PURPOSE: To evaluate intraocular pressure (IOP) after phacoemulsification and intraocular lens (IOL) implantation in nonglaucomatous eyes with and without exfoliation. SETTING: Department of Ophthalmology, Helsinki University Central Hospital, Helsinki, Finland. METHODS: One hundred ninety-six eyes that had phacoemulsification with IOL implantation were examined. Eyes with a history of intraocular disease or surgery that could affect IOP were excluded. The study comprised the remaining 160 eyes: 23 with exfoliation (EXF group) and 137 without exfoliation (non-EXF group). Follow-up data were available for 136 eyes. The same surgeon performed all surgeries. Patients were examined on the first postoperative day and after 1 week, 4 months, and 1.0 to 2.7 years. RESULTS: One day postoperatively, IOP rose in the EXF group from a mean preoperative level of 16.3 mm Hg +/- 2.7 (SD) to 21.0 +/- 8.5 mm Hg, a 28.4% increase (P =.0061). In the non-EXF group, mean IOP rose from 16.2 +/- 3.4 mm Hg to 20.5 +/- 5.7 mm Hg, a 29.9% increase (P =.001). In 4 eyes (17.4%) in the EXF group and 8 eyes (5.8%) in the non-EXF group, IOP increased to 30 mm Hg or higher at 1 day. After this, significant IOP decreases occurred in both the EXF and non-EXF group, respectively, as follows: 14.2 +/- 3.0 mm Hg (12.0% decrease from preoperative value; P =.001) and 15.0 +/- 2.9 mm Hg (5.9%; P =.001) 1 week postoperatively; 12.8 +/- 2.7 mm Hg (20.2%; P =.0002) and 13.8 +/- 2.7 mm Hg (13.2%; P =.001) after 4 months; and 12.3 +/- 2.6 mm Hg (23.2%; P =.0001) and 12.7 +/- 2.7 mm Hg (21.2%; P =.001) after 1.0 to 2.7 years. There was no significant difference between the 2 groups. CONCLUSION: After phacoemulsification with IOL implantation, IOP decreased significantly and remained lower than preoperatively in eyes with and without exfoliation. One day postoperatively, transient pressure peaks were more common in eyes with exfoliation. One eye without exfoliation developed glaucoma.  相似文献   
79.
80.
This study evaluated the accuracy of the interpretation of the chest film in delineating localised abnormalities of ventilation and perfusion, as well as the overall severity of airways obstruction, exercise tolerance, and clinical condition in children with cystic fibrosis. Radiographic findings in various regions of the chest film were compared with the functional values obtained with regional lung function tests which evaluated the arrival and disappearance of boluses of radioactive nitrogen given by inhalation and infusion. While the more severely affected areas on the chest radiograph were found to correlate with similar regions on the lung function tests, as did overall scores, errors occurred in some cases if the x-ray film alone was used as a judge of regional physiological derangement. In addition the degree of airways obstruction, the exercise tolerance on a cycle ergometer, and clinical grading, each correlated significantly with the radiographic score. We conclude that the chest radiograph is a good indicator of the overall severity of the lung disease and that it correlates well with exercise tolerance and clinical condition in cystic fibrosis.  相似文献   
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