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The severely of skin loss and the options of resurfacing is determined by taking into account the following factors. 1) The size & location of the defect, 2) The depth of the defect and the quality of the tissue bed, 3) The extent of exposed vital structures, 4) The associated bone and other tissues injuries, 5) The availability of donor skin flap. The size of the defect is the most important factor in choosing a resurfacing option. The size can be categorized into small, medium and large. A small defect is one that is less than 5 cm2 in size, a medium defect is between 5 to 15 cm2, and a large defect is greater than 15 cm2. Local flaps are usually sufficient to cover small defects <5 cm2. These are advancement flaps or rotation and transposition flaps. Regional flaps are indicated to resurface these medium‐sized defects 5 to 15 cm2. The donor is within the same region of the hand, from one of the digits or from dorsum and palmar surfaces of the hand. It is usually based on vascular or NV pedicles. Large defects >15 cm2 will need larger flaps for coverage. These large flaps are pedicled distant flaps and free flaps. In these severe injuries, there is usually associated bone and soft tissues injuries. These injuries can be reconstructed as a single stage combined reconstruction or multi‐staged reconstructions. The resurfacing should always be given priority.  相似文献   
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The visual acuity, the difference in sensitivity of the two eyes to light (brightness ratio), and contrast sensitivity were assessed in 28 patients with chronic open angle glaucoma and compared with those of 41 normal controls of similar ages and visual acuity. The results obtained were related to the results of Tübingen visual field analysis in patients with glaucoma. Twenty-four of the 28 glaucoma patients (86%) had a significant disparity in brightness ratio between the two eyes. This was found to match the frequency of visual field loss. Moreover, there was a significant relationship between the interocular differences in brightness sense and the difference in the degree of visual field loss between the two eyes. Of the glaucoma patients 39% had sum contrast sensitivities outside the normal range for age-matched normal controls. No significant correlation was found between the interocular difference in brightness sense and the visual acuity or the interocular difference in sum contrast sensitivity. It is concluded that, in the presence of a normal visual acuity, the brightness ratio test warrants evaluation as a potential screening test for chronic open angle glaucoma.  相似文献   
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This study compares the efficacy of omeprazole and ranitidine at reducing gastric secretion in obstetric patients. Sixty-five women scheduled to undergo elective Caesarean section under general anaesthesia were randomly allocated to receive either omeprazole 40 mg or ranitidine 150 mg orally at 2200 hours the night before and at 0600 hours on the morning of surgery. Intragastric pH and volume were measured immediately after induction of anaesthesia and on completion of surgery. All patients had gastric aspirates less than 25 ml. None of the omeprazole group had an aspirate of pH less than 3.5. Six patients (19%) in the ranitidine group had aspirates of pH less than 3.5, a significant difference from the omeprazole group (p less than 0.05). Of these six, two (6%) had aspirates of pH less than 2.5. Hence this study showed that omeprazole was more effective and consistent than ranitidine at maintaining gastric pH greater than 3.5.  相似文献   
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We present a patient with an asymptomatic painless medial elbow swelling of one year's duration, which was diagnosed as a ganglion originating from a non-united avulsion fracture of the medial epicondyle with a pseudarthrosis. Medial elbow ganglia are unusual lesions typically arising from the medial aspect of the ulnohumeral joint capsule, often in combination with symptoms of cubital tunnel syndrome. To our knowledge, a ganglion arising from a pseudarthrosis has not been reported in the literature, and should be considered in the differential diagnoses of lesions encountered over the site of fracture non-union in proximity to a joint.  相似文献   
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Tiaw KS  Goh SW  Hong M  Wang Z  Lan B  Teoh SH 《Biomaterials》2005,26(7):763-769
Ultra-thin polycaprolactone (PCL) produced by bi-axial stretching was previously shown to have significant advantage for membrane tissue engineering. However, the permeability of the membrane needs to be enhanced. In this study, ablation experiments using femtosecond laser and excimer laser were carried out to modify the PCL surface. The use of the femtosecond laser produces neat drilled-through holes while the excimer laser is employed to produce blind-holes on the membrane. The modified surface of the membrane was studied and analyzed for different laser parameters (such as pulse energy and pulse repetition rate and characterized using several techniques that include optical microscopy, scanning electron microscopy and water contact angle measurements). Results showed that the morphological surface changes with different laser parameters, and the water contact angle decreases as the surface of the membrane is modified. The decrease in water contact angle suggests that surface of the membrane had become more hydrophilic than the non-laser treated membrane. The present study demonstrated that laser surface modification on the PCL can be achieved with high degree of success and precision. This paved the way for further enhancement in membrane tissue engineering.  相似文献   
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