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81.
This study was design to reach a better understanding of muscle strength, motor function and activity of daily living in patients of limb-girdle muscular dystrophy. Forty-eight patients diagnosed as cases of limb-girdle muscular dystrophy were included in this study. Manual muscle testing was used to evaluate muscle strength. The Brooke and Vignos scales were used to grade upper and lower extremities function, respectively, and the ability of daily living activity was measured by Barthel index. Our patients showed progressive symmetrical limb-girdle muscular weakness. Upon regression analysis we found that mean muscle strength was inversely related to disease duration (years) as follows: mean muscle strength = 0.6052 + (0.6309/disease duration). According to the Brooke functional scale, 89.6% of our patients were graded as 1-3 and 10.4% were graded as 5. On the Vignos functional scale, 79.1% of patients fell into the grades 1-5, one person (2.1%) in grade 6 and 18.8% in grade 9 category. The average Barthel index was 85.3 +/- 20.7. Mean muscle strength was significantly correlated with the average Barthel, Vignos and Brooke functional scales. Our study could offer the strength and functional performance of limb-girdle muscular dystrophy on natural history. The muscle strength declined in Taiwanese patients of limb-girdle muscular dystrophy in a typical pattern. Regression analysis showed that the strength was inversely related to disease duration. These findings demonstrate that most of our patients suffered from mild or moderate physical disability.  相似文献   
82.
The results of transcatheter valvotomy in pulmonary atresia with intact ventricular septum (PA-IVS) patients are presented with an attempt to identify the predictive factors for pulmonary valvotomy alone as definitive treatment. Between June 1995 and December 1997, 14 PA-IVS neonates with tripartite right ventricle underwent an attempted pulmonary valvotomy. For perforation of the pulmonary valve, a guidewire was used in 4, and a radiofrequency guidewire in 10 patients. Two outcome groups were identified. Group I included those in whom transcatheter treatment achieved a definitive success; group II patients required surgery despite an initial successful valvotomy. The attempt failed in 3 patients, 1 of whom had pericardial effusion. Perforation of the pulmonary valve was achieved in 11 patients: 2 with a guidewire and 9 with a radiofrequency guidewire. A subsequent balloon valvuloplasty was performed in these 11 patients. After valvuloplasty, mean right ventricular pressure decreased from 124 +/- 24 to 60 +/- 15 mm Hg (p <0.01). One died of heart failure and infection 10 days later, despite successful weaning from prostaglandin E1. Group I patients (n = 6) were treated with transcatheter valvotomy alone. Group II patients (n = 4) required right ventricular outflow patch. Significant differences between the 2 groups (group I vs II) were identified in tricuspid valve Z value (0.52 +/- 0.37 vs -1.25 +/- 0.48, p <0.05), pulmonary valve Z value (-3.47 +/- 0.59 vs -5.43 +/- 0.94, p <0.05), and ratio of right-to-left ventricular area on the apical 4-chamber view (0.73 +/- 0.06 vs 0.49 +/- 0.03, p <0.05). There were no significant differences in hemodynamic characteristics between the 2 groups. After a follow-up period ranging from 7 to 35 months (mean 18 +/- 10.3), the most recent echocardiograms in the 10 patients showed a mean pressure gradient across the pulmonary valve of 17 +/- 15 mm Hg. All 10 patients had an oxygen saturation of >92%. Transcatheter valvotomy using a radiofrequency guidewire is a safe and effective treatment in selected patients with PA-IVS. Transcatheter valvotomy can be a definitive treatment in PA-IVS patients with a tricuspid valve Z value > or = -0.1, pulmonary valve Z value > or = -4.1 and ratio of right-to-left ventricular area > or = 0.65.  相似文献   
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84.
Digital beam attenuator technique for compensated chest radiography   总被引:1,自引:0,他引:1  
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.  相似文献   
85.
Summary Numerous revascularization procedures are used for the treatment of vasculogenic impotence. In an animal model we created three different types of bypasses: inferior epigastric artery to dorsal penile artery, to dorsal artery and to dorsal vein (anastomotic arteriovenous fistula), and to dorsal vein alone. Epigastro-dorsal anastomoses remained fully patent without anticoagulants in 3 of 4 animals. With erection the flow in the inferior epigastric artery and the retrograde flow in the dorsal artery (towards the cavernous artery) increased significantly. In the 4 studies incorporating an anastomotic arteriovenous fistula we could not establish a clear reason to incorporate the artery; runoff was demonstrated only to the venous system. Arterial bypass to the dorsal vein with a simulated emissary vein increased outflow resistance as well as improved intracorporeal pressure during erection of the corpora in 4 animals. As resting pressure was also elevated, the penile smooth muscle might be at risk for further degeneration with this procedure.Part of this paper was presented at the 10th Symposium of the Association for Experimental Urology of the German Urological Society, June 21–23, 1990, Munich, FRG  相似文献   
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In the not too distant past, the physician caring for the impotent patient had few therapeutic options. With the recent advances in penile pharmacotherapy, vascular surgery, and prosthetics, several possibilities for treatment are now available. Before a decision is made, however, numerous factors must be taken into consideration: age, manual dexterity, cause of erectile dysfunction, psychological attitude, and social considerations. Clearly, the choice of therapy for impotence must now be made on an individual basis after a careful diagnostic evaluation and in-depth consultation with the patient. Only then can the treatment that offers the highest likelihood of success, both functional and emotional, be chosen.  相似文献   
89.
The increasing popularity of inhaling cocaine vapor prompted the present study, to determine cocaine's fate during this process. The free base of [3H]cocaine (1 microCi/50 mg) was added to a glass pipe, which was then heated in a furnace to simulate freebasing. Negative pressure was used to draw the vapor through a series of glass wool, ethanol, acidic, and basic traps. Air flow rate and temperature were found to have profound effects on the volatilization and pyrolysis of cocaine. At a temperature of 260 degrees C and a flow rate of 400 mL/min, 37% of the radioactivity remained in the pipe, 39% was found in the glass wool trap, and less than 1% in the remainder of the volatilization apparatus after a 10-min volatilization. Reducing the air flow rate to 100 mL/min reduced the amount of radioactivity collected in the glass wool trap to less than 10% of the starting material and increased the amount that remained in the pipe to 58%. GC/MS analysis of the contents of the glass wool trap after volatilization at 260 degrees C and a flow rate of 400 mL/min revealed that 60% of the cocaine remained intact, while approximately 6 and 2% of the starting material was recovered as benzoic acid and methylecgonidine, respectively. As the temperature was increased to 650 degrees C, benzoic acid and methylecgonidine accounted for 83 and 89% of the starting material, respectively, whereas only 2% of the cocaine remained intact. Quantitation of cocaine in the vapor during the course of volatilization revealed high concentrations during the first two min and low concentrations for the remaining time.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
90.
OBJECTIVE: Outer hair cells (OHCs) of the inner ear rapidly convert electrical gradients into mechanical force, enhancing cochlear sensitivity and frequency selectivity. We investigated the effect of chlorpromazine, an antipsychotic medication that alters membrane biomechanics, on OHC electromotility. STUDY DESIGN: Isolated guinea pig outer hair cells were perfused with chlorpromazine under whole-cell patch-pipette recording conditions. Electromotile responses were measured. RESULTS: A dramatic, reversible, dose-dependent depolarization of voltage at peak capacitance (V(pkCm)) was seen with chlorpromazine treatment. The gain of the electromotile response was maximal near V(pkCm) both before and after chlorpromazine application. Unlike the 3 other agents that alter electromotility (salicylate, lanthanides, membrane tension), chlorpromazine did not change peak capacitance (Cm(pk)), which varies directly with maximal electromotile gain. CONCLUSION: Chlorpromazine changes the membrane voltage at which OHCs exhibit maximal electromotile gain, without changing the magnitude of electromotile responses. SIGNIFICANCE: Chlorpromazine may diminish hearing thresholds or otoacoustic emissions in large doses.  相似文献   
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