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Journal of the American Oil Chemists' Society - 1 相似文献
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OBJECTIVE: To identify and examine the indications, outcomes and potential risks of strabismus surgery in visually mature patients. DESIGN: Case series. SETTING: University-based referral practice in Edmonton. PATIENTS: A total of 222 patients (115 females and 107 males) aged 9 to 69 (mean 29) years who underwent strabismus surgery for various types of strabismus (as grouped by original diagnosis). All patients were followed for at least 6 weeks postoperatively. OUTCOME MEASURES: Previous surgery and deviation in prism dioptres (delta) (distance and near), sensory status (measured by the Titmus stereotest at near) and the presence of symptoms (diplopia, abnormal head posture or asthenopia), recorded preoperatively, 6 weeks postoperatively and at the last postoperative visit. RESULTS: The patients were followed for an average of 14 months postoperatively. At the last postoperative visit 187 patients (84%) were aligned to within 15 delta of orthotropia. Overall, 116 patients (52%) demonstrated some degree of stereopsis postoperatively, compared with 78 (35%) preoperatively. A total of 116 patients (52%) had symptoms preoperatively, including diplopia, abnormal head posture or asthenopia; 88 (76%) of the 116 had complete resolution of their symptoms. Six patients (4%) without diplopia preoperatively were found to have this symptom postoperatively. CONCLUSIONS: The findings suggest that most visually mature patients under-going strabismus surgery can expect functional benefits, including improvement of alignment, preservation and occasionally restoration of sensory fusion, and elimination of diplopia, abnormal head posture and asthenopia. 相似文献
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LH Carvalho CJ Fontes AA Fernandes HC Marinuzzi AU Krettli 《Canadian Metallurgical Quarterly》1997,19(2):47-59
The present review offers a new look at capillary isoelectric focusing (cIEF) by centering on the most troublesome aspects of the technique, namely: 1) how to modulate the slope of the pH gradient, for increasing resolution (equivalent to pH gradient engineering, as easily available in immobilized pH gradients); and 2) how to keep proteins in solution at (and in the proximity of) the pl value. A simple solution is offered in the first case: addition, to the standard 2-pH-units interval, of separators or spacers, i.e., of amphoteric molecules (either single or in combination) able to locally flatten the pH and increment resolution. Examples of the separation of fetal and glycated hemoglobins are provided. In the second case, a unique solubilization power (while maintaining full protein integrity and enzyme activity) is obtained if class I solubilizers are used. They consist of mixtures of sugars (e.g., sucrose and sorbitol) at ca. 1 M concentration, with zwitterions (up to 1 M) such as the class of nondetergent sulfobetaines, but also taurine and some of the Good's buffers (e.g., CAPS). In these solvents, the protein exists in a state of superhydration and its solubility is greatly augmented. The review ends with an excursus on the use of isoelectric buffers in zone electrophoretic separations. Such isoelectric buffers offer unique advantages: They permit very-high-voltage gradients (up to 1000 V/cm) and thus minimize analysis times (down to a few min in 30-35 cm long capillaries). This results in a marked increase in resolution, due to minimal diffusion-driven peak spreading. Such buffers are finding unique applications for generating peptide maps of tryptic digests of proteins and also in the analysis of oligonucleotides. 相似文献
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Early surgery in patients with mitral regurgitation due to flail leaflets: a long-term outcome study
LH Ling M Enriquez-Sarano JB Seward TA Orszulak HV Schaff KR Bailey AJ Tajik RL Frye 《Canadian Metallurgical Quarterly》1997,96(6):1819-1825
BACKGROUND: The optimal timing for surgery in patients with mitral regurgitation is disputed. Because of the frequency of left ventricular dysfunction, which is difficult to predict, early surgery has been recommended, but its potential benefits have not been demonstrated. METHODS AND RESULTS: The outcomes of 221 patients (mean age, 65 +/- 13 years; 71% males) with flail leaflets diagnosed with two-dimensional echocardiography between 1980 and 1989 who were eligible for operation were analyzed. Group I comprised 63 patients who had early mitral valve surgery (within 1 month after diagnosis). Group II comprised 158 patients initially treated conservatively (80 of whom were operated on later). Group I patients were younger (P=.009), had more symptoms (P<.0001), and were more frequently in atrial fibrillation (P=.023) than group II patients. There was no difference in ejection fraction between the groups. The early surgery strategy was followed by an improved overall survival rate (P=.028) and a lower incidence of cardiovascular deaths (P=.025), congestive heart failure (P=.046), and new chronic atrial fibrillation (P=.032), as confirmed by multivariate analysis (adjusted risk ratios of 0.31, 0.18, 0.38, and 0.05, respectively; all P<.02). CONCLUSIONS: In patients with mitral regurgitation due to flail leaflets, the strategy of early surgery versus conservative management is associated with an improved long-term survival rate, decreased cardiac mortality, and decreased morbidity after diagnosis. This outcome advantage suggests that early surgery is a reasonable treatment option to be considered in low-risk candidates with repairable valves and severe mitral regurgitation. 相似文献