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PURPOSE: Cryotherapy and indirect laser retinal photoablation are both effective in the treatment of retinopathy of prematurity (ROP). We describe the safety, efficiency, and effectiveness of combined cryotherapy and diode laser photocoagulation to treat threshold ROP. METHODS: Records of patients developing threshold ROP from January 1, 1996 through December 31, 1998, were retrospectively reviewed to identify those treated with combined cryotherapy and photocoagulation and followed up for at least 45 days postoperatively. Diode laser was used to ablate posterior avascular retina, and cryotherapy was used for anterior retina. Data reviewed included ocular and systemic complication rates, treatment duration, number of laser burns, most recent fundus examination, visual acuity, and refraction. RESULTS: In 13 patients, 23 eyes received combined treatment. No intraoperative complications occurred. Mean duration of anesthesia and treatment was 35 +/- 8 minutes/eye. A mean of 117 +/- 84 laser burns/eye were applied. In 20 of 23 eyes (87.0%), anatomic outcome was favorable at last examination. In 13 of 16 eyes (81.3%), functional (visual acuity) outcome was favorable (visual acuity better than 20/200) at 1 year. At 6 months or later, 14 of 16 eyes (87.5%) measured were myopic, of which 5 (31.3%) were highly myopic (> 6 diopters). CONCLUSIONS: The effectiveness of treating ROP with combined cryotherapy and diode laser photocoagulation compares with that of either modality alone. By decreasing the number of laser applications, combined therapy may be faster and technically easier for eyes with very posterior ROP. This may decrease the number of complications seen when either excessive cryotherapy or laser retinal photoablation is used. 相似文献
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We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder. 相似文献
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J Saunders M Cassidy S B Freedman E A Harley L L Iversen C Kneen A M MacLeod K J Merchant R J Snow R Baker 《Journal of medicinal chemistry》1990,33(4):1128-1138
Recent clinical studies on Alzheimer's patients have implied that only agents displaying high efficacy at the cortical muscarinic receptor have yielded encouraging results. This paper describes the design, synthesis, and biochemical characterization of novel quinuclidine-based muscarinic agonists which can readily penetrate into the central nervous system and which are capable of displaying high efficacy at cortical sites. With use of a biochemical assay capable of measuring receptor affinity and predicting cortical efficacy, it has been discovered that an oxadiazole ring and related heterocycles can function as bioisosteric replacements for the ester moiety found in several known muscarinic ligands. Within this series there exist compounds which span the efficacy range from high-efficacy agonist through partial agonists to antagonists with affinity comparable or superior to that of classical quaternary ammonium ligands. Consistent with recent molecular biology studies, structure-activity trends are interpreted in terms of separate binding sites for agonists and antagonists with H-bonding interactions characterizing agonist behavior and lipophilic binding characterizing antagonist behavior. Thus the aminooxadiazole moiety has structural features which are optimized for an agonist profile. 相似文献
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A novel series of non-quaternary oxadiazoles acting as full agonists at muscarinic receptors 总被引:2,自引:2,他引:0
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S B Freedman E A Harley S Patel N R Newberry M J Gilbert A T McKnight J K Tang J J Maguire N T Mudunkotuwa R Baker 《British journal of pharmacology》1990,101(3):575-580
1 A novel series of non-quaternary oxadiazole-based muscarinic agonists demonstrated high affinity for muscarinic receptors. 2. These agonists possessed high efficacy in the nanomolar range at muscarinic receptors in the superior cervical ganglion, atrium and ileum but did not show selectivity across the tissue preparations. 3. Two amino oxadiazoles, one from a quinuclidine series (L-660,863) and one from a 1-azanorbornane series (L-670,207) possessed a high ratio of potency for displacing the binding of [3H]-N-methyl-scopolamine ([3H]-NMS) to potency for displacing the agonist [3H]-oxotremorine-M cortex. 4. The two azanorbornane derivatives L-670,548 and L-670,207 stimulated the turnover of phosphatidylinositol in the cortex with a potency higher than that obtained with any other known muscarinic agonist (ED50 0.26 and 0.18 microM respectively). 5. The maximum response obtained with L-670,207 was greater than that observed for carbachol but was comparable to that of the natural ligand acetylcholine. 6. These oxadiazole muscarinic agonists are among the most potent and efficacious non-quaternary muscarinic agonists ever described. 相似文献
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Charles S Cornford Jan Harley Nigel Oswald 《The British journal of general practice》2004,54(505):584-588
BACKGROUND: The '2-week rule' for the referral of patients with potential cancers is an important but controversial development. AIMS: To investigate the 2-week rule for women with breast problems from the perspective of the patients and of healthcare professionals. DESIGN OF STUDY: Qualitative study using semi-structured interviews. SETTING: Patients referred to two breast care units and professionals from primary and secondary care in Teesside and Hartlepool. METHOD: Semi-structured interviews with a purposive sample of 12 patients referred under the 2-week rule and 20 professionals. RESULTS: All women experienced considerable worries in the time leading up to diagnosis. This affected relationships with others, and they used selective telling to help maintain control over their own anxiety and prevent anxiety in others. They were not aware of the 2-week rule as a new initiative, but wanted quick referral to assure them that they did not have cancer. Patients felt they needed more information about breast symptoms and the referral process. Comments about communication with professionals, both good and poor, were frequent in their accounts, which contrasted with the absence of such concerns in the accounts of the professionals. The professionals thought that the 2-week rule was advantageous in reducing anxiety, but thought that disadvantages included longer waits for patients referred outside the rule and increased pressure on hospital services. Cultural changes, including increased patient assertiveness and 'breast awareness', were considered important contextual factors. General practitioners (GPs) were concerned about missing diagnoses in patients statistically unlikely to have carcinomas. CONCLUSION: Differences in emphasis were apparent, with patients wanting to be assured that they did not have cancer, specialists concerned both about increased workload and the impact on patients with cancers, and GPs anxious about missing diagnoses. The 2-week rule compromises professional autonomy, which partially accounts for the anger directed against it. There is a need for patients to have more information, and they place great value on good communication. All patient responders experienced significant distress while waiting to be seen. 相似文献
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