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D G Ray R Subramanyan T Titus J Tharakan J Joy C G Venkitachalam K G Balakrishnan 《International journal of cardiology》1992,36(3):273-281
Balloon angioplasty was performed in 46 patients (age 2-40 yr) with discrete native coarctation of aorta. Patients with associated patent ductus arteriosus, aberrant subclavian artery and aneurysms were excluded. The peak systolic gradient across the coarcted segment decreased from 52.1 +/- 18.5 mmHg to 18.6 +/- 14.8 mmHg (p less than 0.001), and the diameter of the coarcted segment increased from 3.6 +/- 1.7 mm/m2 to 9.1 +/- 3.2 mm/m2 (p less than 0.001). Follow-up haemodynamic and angiographic studies performed in 21 patients at 13.1 +/- 6.9 months after angioplasty, showed good results in 15 patients. Four patients undergoing haemodynamic study and 4 other patients undergoing noninvasive evaluation were graded as having bad results at follow-up. In 5 of these patients the poor results were due to primary failure of angioplasty in relieving the gradient, and three developed re-coarctation after initial fall in the trans-coarctation gradient. Four risk factors were identified on univariate analysis, which were associated with significantly larger residual gradients at follow-up: (1) size of isthmus/size of coarcted segment ratio less than 3.0; (2) size of post-coarctation descending aorta/size of isthmus ratio greater than 1.75; (3) size of coarcted segment after angioplasty/size of coarcted segment before angioplasty ratio less than 2.0; and (4) size of balloon/size of coarcted segment ratio less than 3.0. The presence of one or more risk factors was associated with bad late results. On multivariate analysis the ratio of balloon size/coarcted segment size was found to be the sole independent predictor of the late outcome (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
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Benefits of glucose and oxygen in multidose cold cardioplegia. 总被引:3,自引:0,他引:3
N E Doherty J F Turocy G A Geffin D D O'Keefe J S Titus W M Daggett 《The Journal of thoracic and cardiovascular surgery》1992,103(2):219-229
We tested the effects of glucose and oxygen in cardioplegic solutions on myocardial protection in the isolated perfused working rat heart. Recovery from 2 hours' hypothermic (8 degrees C) cardioplegic arrest was examined in 93 hearts. Cardioplegic solution, which was delivered every 15 minutes, was supplemented with glucose 28 mmol/L as a substrate or sucrose 28 mmol/L as a nonmetabolizable osmotic control; it was equilibrated with either 98% oxygen or 98% nitrogen, both with 2% carbon dioxide. Four combinations of hyperkalemic cardioplegic solution were studied: nitrogen-sucrose, nitrogen-glucose, oxygen-sucrose, and oxygen-glucose. During hypothermic arrest, oxygenation of cardioplegic solution greatly reduced myocardial lactate production and prevented ischemic contracture as indicated by coronary vascular resistance. Glucose increased lactate production modestly but significantly only when the cardioplegic solution was nitrogenated. Although end-arrest myocardial adenosine triphosphate and creatine phosphate were greatly increased by oxygenation of cardioplegic solution (p less than 0.005), we could not detect improved preservation of these high-energy phosphates by glucose. Averaged over reperfusion, percent recovery of cardiac output for the nitrogen-sucrose, nitrogen-glucose, oxygen-sucrose, and oxygen-glucose solutions was 32.3% +/- 6.1%, 45.9% +/- 4.6%, 44.5% +/- 4.6%, and 62.2% +/- 4.5%, respectively. Oxygenation of the glucose solution or addition of glucose to the oxygenated solution significantly improved recovery of cardiac output. The benefits of glucose and oxygen were additive, so that the oxygen-glucose cardioplegic solution provided the best functional recovery. We conclude that the addition of glucose to the fully oxygenated multidose cold cardioplegic solution improves functional recovery without increasing lactate production during arrest. 相似文献
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According to current research findings, women are more likely than men to suffer from depression, eating disorders, and multiple personality disorder. The authors review recent advances in the understanding of female psychology, family systems theory, and psychoanalytic theory to show how women's unique developmental challenges and complex social conditions interact to determine the form and expression of these disorders. After discussing contributing factors, the authors suggest appropriate approaches to diagnosis and treatment. They conclude that therapists of both genders must appreciate the complex causes of these disorders to be most helpful to their female patients. 相似文献
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导数光谱系数倍率法测定多组分体系感冒清胶囊中盐酸吗啉胍的含量 总被引:1,自引:0,他引:1
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12). 相似文献
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CONTEXT: The knowledge of variations of the tympanic membrane (TM) perforations with the climatic changes in the West African subregion would help clinicians in its prevention and management. OBJECTIVE: To analyze the pattern of clinical presentations and associated features of TM perforation in adults in West Africa. DESIGN: A prospective study. SETTING: Tertiary referral centre, University hospital. PATIENTS OR OTHER PARTICIPANTS: Thirty-five (35) consecutive adults with TM perforations during a 1-year period had clinical evaluation of each TM using head mirror, video otoscopy, and micro-otoscopy. MAIN OUTCOME MEASURES: Clinical presentations and associated features of TM perforations. RESULTS: Thirty-five patients, 20 (57%) men and 15 (43%) women, with 42 perforated TMs were examined. Twenty-eight (80%) patients had unilateral perforations. Infection was responsible for 90.5% of cases, and trauma was responsible for the rest. Locations of perforations were central (29; 69.1%), anteroinferior (4; 9.5%), posteroinferior (4; 9.5%), anterosuperior (3; 7.1%), and posterosuperior (2; 4.8%). The sizes of the perforations ranged from 1.2 to 83.2%. Large sizes of 25% and more were found to occur in humid and wet seasons, and also, clinical presentations of otorrhea (65.6%), otalgia (51.5%), tinnitus (37.1%), and ear itching (34.4%) seemed to worsen. CONCLUSION: Most TM perforations result from infection and are preventable via appropriate health education. Posterosuperior perforation is rare, and this is probably one of the factors making choleasteatoma uncommon in West Africa. Approximately 83.3% of TM perforations measure more than 25% in size and appear during the wet humid season of the year. These findings are important for both local and foreign otolaryngologists who may be practicing in this subregion of the world. 相似文献