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21.
William Davies Mohammad Jazayeri Patrick Tchou 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1988,2(3):283-286
Summary Encainide is a type Ic antiarrhythmie agent. During encainide therapy, mild Q-T interval prolongation can be seen, usually associated with prolongation of the Q-R-S interval. The present case report describes an unusual and marked prolongation of the Q-T interval with no Q-R-S interval prolongation in a patient who was treated with encainide for atrioventricular nodal reentrant tachycardia. The drug metabolite profile in this patient's serum indicated an unusual elevation of the 3-methoxy-O-demethyl encainide metabolite, versus O-demethyl encainide. This elevated metabolite level suggests that 3-methoxy-O-demethyl encainide has a significant effect on prolongation of repolarization. An abnormal metabolism of encainide may be the underlying mechanism by which some patients would manifest an unusual prolongation of Q-T interval during encainide therapy. 相似文献
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24.
Mohammad Diab Jiann-Jiu Wu Frederic Shapiro David Eyre 《American journal of medical genetics. Part A》1994,49(4):402-409
There is growing evidence that a spectrum of chondrodysplasias are caused by mutations in the gene coding for type II collagen. The basic molecular defect in diastrophic dysplasia has not been defined, but it appears not to be in collagen type II. Cartilage contains other tissue-specific collagens, types IX, X, and XI, but no mutations have yet been found in their genes in clinical disease. Type IX collagen is hypothesized to play a role in the regulation of type II collagen fibril organization and structure in cartilage extracellular matrix. In this study, we have examined iliac crest growth cartilage from a patient with diastrophic dysplasia. Although collagen fibrils were markedly increased in diameter on transmission electron microscopy, type II collagen appeared to be normal biochemically. Type XI collagen was also normal. However, type IX collagen appeared abnormal on sodium dodecyl sulfate polyacrylamide gel electrophoresis with a pronounced excess of the COL1 domain of the molecule in pepsin extracts. The findings point to an abnormality in structure or metabolism of type IX collagen in diastrophic dysplasia. © 1994 Wiley-Liss, Inc. 相似文献
25.
Quantification of hydroxyl radical and its lack of relevance to myocardial injury during early reperfusion after graded ischemia in rat hearts. 总被引:4,自引:0,他引:4
To elucidate the pathophysiological role of the hydroxyl radical (.OH) during the postischemic reperfusion of the heart, we measured the .OH product in the coronary effluent from isolated perfused rat heart during a 30-minute reperfusion period after various ischemic intervals of 5, 10, 15, 20, 30, and 60 minutes. Salicylic acid was used as the probe for .OH, and its derivative, 2,5-dihydroxybenzoic acid (2,5-DHBA), was quantified using high-performance liquid chromatography with ultraviolet detection. 2,5-DHBA was negligible in the effluent from nonischemic hearts, but a significant amount was detected from the hearts rendered ischemic for 10 minutes or longer. The peak of 2,5-DHBA was seen within 90 seconds after the onset of reperfusion in every group. The accumulated amount of 2,5-DHBA was maximal in the group with 15-minute ischemia (6.73 +/- 1.04 nmol/g wet heart wt after 30 minutes of reperfusion); it decreased as the ischemic time was prolonged and was 2.38 +/- 0.84 nmol/g wet wt after 30 minutes of reperfusion in the group with 60-minute ischemia. In the model of 15-minute ischemia/30-minute reperfusion, there was no correlation between the accumulated amount of 2,5-DHBA and functional recovery (+/- dP/dt, heart rate, and coronary flow), lactate dehydrogenase release, and morphological damage. Although treatment with 0.5 mM deferoxamine, an iron chelator, significantly decreased 2,5-DHBA (from 6.73 +/- 1.04 to 2.29 +/- 0.80 nmol/g wet wt after 30 minutes of reperfusion, p less than 0.01), it failed to reduce the postischemic myocardial injury in the group with 15-minute ischemia. The results suggest that .OH production is influenced by the preceding ischemic interval and that .OH does not exert an immediate direct effect on postischemic damage during early reperfusion in the isolated perfused rat heart, although a possibility remains that the small portion of .OH trapped by salicylic acid may not be intimately associated with myocardial injury. 相似文献
26.
Despite the controversy of airway responsiveness to beta2-agonist drugs in asthma, in a previous study we showed increased responsiveness of asthmatic airways to isoprenaline. Therefore, in the present study of airway sensitivity to other beta2-agonists, salbutamol and its relationship to histamine responsiveness was reexamined. The threshold bronchodilator concentrations of inhaled salbutamol required for a 20% increase in forced expiratory flow in 1 sec (FEV1), (PC20) was measured in 20 normal and 19 asthmatic adults. Airway responsiveness to histamine, as the concentration that caused a 20% decrease in FEV1, was also measured in 11 normal and 12 asthmatic subjects; and the correlation between PC20 salbutamol and PC20 histamine was evaluated. Sensitivity to salbutamol was greater in asthmatics (PC20 = 7.24 mg/L) than in non-asthmatics (PC20 = 124.25 mg/L, p < 0.001). Airway responsiveness to histamine in asthmatics (PC20 = 0.18 g/L) was also significantly greater than in normal subjects (PC20 = 19.46 g/L, p < 0.001). There was a significant correlation between PC20 salbutamol and histamine (Rs = 0.6052, p < 0.005). Maximum response to both salbutamol and histamine and slope of concentration-response curves of both agents were significantly greater in patients with asthma than in normal subjects (p < 0.001 and p < 0.005 for maximum response and slope, respectively). The increased sensitivity of asthmatics to inhaled salbutamol suggests that they also may be more sensitive to their endogenous adrenaline, which may thus dilate and stabilize their airways. 相似文献
27.
Duane retraction syndrome has been reported in association with structural abnormalities of the eye, including epibulbar dermoid, keratoconus, iris dysplasia, heterochromia iridis, persistent fetal vasculature, cataract, choroidal coloboma, microphthalmia, and optic nerve dysplasia. A novel association, that of bilateral Duane syndrome with bilateral aniridia, is the subject of this report. 相似文献
28.
S. Kumar N. H. Dar M. Ashraf S. C. Sharma V. Maheshwari 《Indian journal of otolaryngology and head and neck surgery》2004,56(1):37-39
We report a cast of ossifying fibroma of the nose, arising from the bony septum and extending into the nasophaynx in a 2 yrs.
old child presenting with features of obstructed nose. 相似文献
29.
Sedigheh Sadat Tavafian Ahmadreza Jamshidi Kazem Mohammad Ali Montazeri 《BMC musculoskeletal disorders》2007,8(1):21
Background
Different interventions can reduce the burden of the chronic low back pain. One example is the use of a 'Back School Programme'. This is a brief therapy that uses a health education method to empower participants through a procedure of assessment, education and skill development. This study aimed to evaluate to what extent the programme could improve quality of life in those who suffer from the condition. 相似文献30.
Mohammad H. Ebrahimzadeh MD Mohammad T. Rajabi MD 《The Journal of foot and ankle surgery》2007,46(6):429-433
Long-term clinical and functional outcomes for patients undergoing foot and ankle amputations are not well documented. We attempted to document long-term outcomes for patients who required lower extremity amputations as a result of wounds suffered during wartime. For this study, 27 Iranian soldiers who had wounds requiring amputation of the foot and ankle were selected for follow-up. The participants' wartime medical records were reviewed, a clinical examination was performed, and each participant completed a questionnaire. Postamputation follow-up averaged 17.5 years. The most prevalent (66.6%) cause of injury was a land mine. The prevalences of different clinical symptoms reported by the amputees at the time of the last follow-up were as follows: 11 (40.7%) with phantom sensation, 6 (22.2%) with phantom pain, 12 (44.4%) with stump pain, 12 (44.4%) with back pain, 9 (33.3%) with contralateral knee pain, and 4 (14.8%) with ipsilateral knee pain; 20 (74%) reported treatment for psychological conditions. In regard to social conditions, 13 (48.1) were currently employed, or had been employed, for a number of years after the amputation; 26 (96%) had children, and all of the patients were married. The results of this observational study indicate that individuals have significant long-term pain and discomfort after war-related lower extremity amputation. Although all 27 (100%) of the amputees were able to maintain satisfactory family functioning, only 13 (48.1%) of the study participants were able to remain productively employed after undergoing amputation, and 20 (74%) reported long-term psychological problems in addition to their physical pain. 相似文献