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61.
Clinically significant contact lens induced corneal warpage is seen in a small proportion of soft and rigid contact lens wearers. Previous studies using the keratometer have found no correlation between the fit of the lens and the induced topographic changes. In this study, using computer-assisted topographic analysis, seven eyes (four patients) with rigid contact lens-induced corneal warpage were noted to have topographic abnormalities that correlated with the decentered resting position of the contact lens on the cornea. The warpage topography for each of these corneas was characterized by a relative flattening of the cornea underlying the resting position of the contact lens. Lenses that rode high, for example, produced flattening superiorly and resulted in a relatively steeper contour inferiorly that simulated the topography of early keratoconus patients who had not worn contact lenses. After discontinuing contact lenses the corneal topography returned to a normal pattern in five eyes. Two eyes retained asymmetry that is not characteristic of normal corneas. Up to 6 months was required for the corneas to return to a stable topography after contact lens wear was discontinued.  相似文献   
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Elevation of prostaglandins and protein in the aqueous humor is an immediate response to Yag-laser anterior capsulotomy. There was a significant correlation between prostaglandins and thromboxane to the elevation of intraocular pressure. The elevation of protein concentration was proportional to the elevation of prostaglandin F1, but not to thromboxane. The biochemical changes in the aqueous humor were more severe as laser power was increased above 3 mj. While the role of prostaglandins in the elevation of intraocular pressure is uncertain, the present data recommend the selection of laser power below 3 mj to avoid pressure rise instead of inhibition of all prostaglandin synthesis by medication.  相似文献   
64.
Single-agent chemotherapy of metastatic breast cancer is the treatment of choice in patients with slow tumor progression and asymptomatic disease. In this patient group, the choice of drugs is based more on good tolerability than on efficacy. By contrast, symptomatic or rapidly progressing disease requires the use of highly active regimens where more weight is put on reliable antitumor activity. While anthraycline-based combination regimens have set the standard of effective treatment, the addition of docetaxel (and to a lesser extent paclitaxel) has improved tumor response, but failed to induce a consistent prolongation of survival. Based on retrospective analyses, it is hypothesised that the combined use of anthracyclines and taxanes in first-line therapy may be most beneficial in defined subgroups: after adjuvant chemotherapy, in patients with HER-2 gene amplification, possibly also in patients with rapidly progressing visceral disease.  相似文献   
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Antegrade interlocking nailing of humeral shaft fractures   总被引:5,自引:0,他引:5  
The results of 39 humeral shaft fractures (37 patients) treated with antegrade locked nailing using a Russell–Taylor nail were reviewed. There were 30 acute fractures, 6 fractures malaligned in a hanging cast or brace, and 3 pathological fractures. Patient age ranged from 26 to 80 years (average, 59.7 years) and average follow-up was 25.7 months (range, 6–48 months). Fracture union was achieved in 92.3% of our cases, while shoulder function was excellent or good in 87.2% of cases. Antegrade locked nailing offers a dependable solution for the treatment of humeral shaft fractures, especially in polytrauma patients and cases of segmental or pathological fractures. Far less satisfactory results were obtained in comminuted fractures of the proximal third in the humerus, especially in osteoporotic patients, and we therefore advocate caution with the use of intramedullary nailing in this type of fracture. Certain technical aspects such as avoiding nailing the fracture in distraction, properly countersinking the tip of the nail, and achieving adequate fixation stability have been found to be of paramount importance to reduce the incidence of delayed union/non-union rate and to obtain better functional results from the shoulder joint.  相似文献   
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本文作者比较了不同时期的纸质病案的使用率,讨论了旧病案的缺点,如难于保存,占用空间及实用价值不大.作者提出了改进保存病案的办法.  相似文献   
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Conclusion In the year 2003 there is no “one best bariatric operation” for every severely obese patient. The choice of operation must be tailored to each individual patient’s needs and wishes. For the superobese patient, the patient diagnosed with intestinal metaplasia of the stomach, and for those patients who do not wish to undergo the severe dietary restrictions imposed by the RNY-GB, the BPD-DS is a valuable surgical option.  相似文献   
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