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排序方式: 共有2267条查询结果,搜索用时 175 毫秒
1.
David Simon Koray Tascilar Sara Unbehend Sara Bayat Andreas Berlin Anna-Maria Liphardt Timo Meinderink Juergen Rech Axel J Hueber Georg Schett Arnd Kleyer 《Journal of bone and mineral research》2020,35(9):1695-1702
The impact of primary hand osteoarthritis (HOA) on bone mass, microstructure, and biomechanics in the affected skeletal regions is largely unknown. HOA patients and healthy controls (HCs) underwent high-resolution peripheral quantitative computed tomography (HR-pQCT). We measured total, trabecular, and cortical volumetric bone mineral densities (vBMDs), microstructural attributes, and performed micro–finite element analysis for bone strength. Failure load and scaled multivariate outcome matrices from distal radius and second metacarpal (MCP2) head measurements were analyzed using multiple linear regression adjusting for age, sex, and functional status and reported as adjusted Z-score differences for total and direct effects. A total of 105 subjects were included (76 HC: 46 women, 30 men; 29 HOA: 23 women, six men). After adjustment, HOA was associated with significant changes in the multivariate outcome matrix from the MCP2 head (p < .001) (explained by an increase in cortical vBMD (Δz = 1.07, p = .02) and reduction in the trabecular vBMD (Δz = −0.07, p = .09). Distal radius analysis did not show an overall effect of HOA; however, there was a gender-study group interaction (p = .044) explained by reduced trabecular vBMD in males (Δz = −1.23, p = .02). HOA was associated with lower failure load (−514 N; 95%CI, −1018 to −9; p = 0.05) apparent in males after adjustment for functional status. HOA is associated with reduced trabecular and increased cortical vBMD in the MCP2 head and a reduction in radial trabecular vBMD and bone strength in males. Further investigations of gender-specific changes of bone architecture in HOA are warranted. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research. 相似文献
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O Koray Coskunfirat Omer Ozkan 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(12):1336-1341
Reversed flaps from the forearm have been firmly established for hand coverage. Each has its own advantages and disadvantages. The reversed anterior interosseous flap is one option with special advantages in hand reconstruction. From January 2002 to July 2003 we used this flap in five consecutive male patients aged between 36 and 59. The defects were located on the first web space (2), on the dorsal side of the thumb (1), on the first metacarpal bone (1), and on the volar side of the wrist (1). Flap size was between 6 x 3 cm and 11 x 7 cm. All flaps healed without any problem and no complication was observed during the postoperative period. The major advantage of this flap is the preservation of the main arteries of the upper limb. Other advantages are as follows: good texture and colour for hand reconstruction, satisfactory rotation arc, and availability of composite and fascial flaps. Besides its advantages, the major disadvantages are unsightly donor area scar and the need for meticulous technique. As a conclusion, we found this flap very useful in hand reconstruction for coverage of small and moderate sized soft tissue defects of the hand. 相似文献
4.
Omer Ozkan O Koray Co?kunfirat Ozlenen Dogan H Ege Ozgenta? 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(5):556-562
Reverse-flow flaps are currently particularly used for the reconstruction of defects of the distal part of the extremities. Despite their common usage there have been many reports of postoperative complications, especially resulting in partial or total flap necrosis. There is insufficient knowledge of flap haemodynamics, physiology and wound healing properties in reverse-flow flaps. Development of the proper experimental models is needed to investigate these issues. The purpose of this study was to describe a new reverse-flow flap model in the rat. A total of 20 adult Wistar rats weighing 200-250 g were used in this experiment. In five rats, the vascular anatomy of the auricle of the rat was determined by anatomic dissection and microangiography. In the experimental group (N=5), 1x1 cm reverse-flow composite flaps were harvested as a semi-island shape, based on the distal course of the medial branch of the anterior auricular artery. In the control group, consisting of five rats, the flap was designed and raised based on the proximal course of the medial auricular artery, again in a semi-island shape. In the remaining five animals, a square-shaped composite tissue of the whole layer of the auricle, 1x1 cm in size, was harvested dividing all the bases circumferentially. The composite tissue was replaced in situ. While the former was considered a conventional antegrade-flow flap subgroup, the latter was designated as a graft subgroup. All flaps were replaced in situ. The survival of the flap was evaluated on postoperative day 7 by direct observation and microangiography. The skin island of all the reverse-flow flaps and conventional antegrade-flow flaps survived completely giving a success rate of 100%, whereas all grafts in the control group underwent complete necrosis. Microangiographic studies revealed the vascularity of the reverse-flow and antegrade-flow flaps, identifying the course of the auricular arteries. In conclusion, with its evident advantages of easy to design and harvesting, reliable survival pattern and consistent vascular structure, our new flap model will provide a means for future studies on flap haemodynamics, physiology in reverse-flow flaps. 相似文献
5.
T. Aköz B. Erdoğan M. Görgü M. R. Kapucu O. Girgin 《European journal of plastic surgery》1998,21(6):308-310
Camptodactyly is a flexion deformity of the proximal interphalangeal joint. Because of unsatisfactory results, treatment is
not recommended for mild deformities, and in severe deformities surgery has been disappointing. A specially designed external
fixator providing gradual distraction was used in a severe case. With this mildly aggressive method, an acceptable result
was obtained.
Received: 5 June 1997/Accepted: 2 February 1998 相似文献
6.
Cemal Şenyuva Akın Yücel Yagmur Aydın Ihsan Okur Zeki Güzel 《Aesthetic plastic surgery》1997,21(4):233-239
Extracorporeal septoplasty is a radical solution for the severely deviated nose. The major problems associated with this
procedure are fixation of the septal cartilage graft and dorsal irregularities. Extracorporeal septoplasty was performed in
combination with open rhinoplasty in 17 patients with severe nasal deformities. In this technique septum was totally removed
through the columellar incision of open rhinoplasty, corrected outside, and replaced as a free ``L' shaped cartilage graft.
The cartilage graft was fixated to the upper lateral cartilages to restore the natural relations of the anatomical structures.
Additional rhinoplastic manipulations were also performed. The follow-up period was up to 18 months. The overall result was
successful in all patients. Nasal deviation did not recur and secondary revisions were not needed for any patient during follow-up. 相似文献
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8.
H H Vincent E Ak?ahuseyin M C Vos F J van Ittersum W A van Duyl M A Schalekamp 《Nephrology, dialysis, transplantation》1990,5(12):1031-1037
In continuous arteriovenous haemofiltration (CAVH) or haemodiafiltration (CAVHD), it is important to obtain an adequate blood flow through the haemofilter to minimise the risk of excessive haemoconcentration and clotting. In this study we determined the resistance to blood flow of the extracorporeal device as well as the hydraulic permeability of the filter membrane is intensive care patients treated with CAVHD. Data were obtained for CAVH catheters and Scribner shunts and for a polyacrylonitrile (AN-69) plate filter, an AN-69 capillary filter and a polysulphone (PS) capillary filter. In accordance with recent literature we also predicted the resistance to flow by using Poiseuille's law and a formula for the estimation of blood viscosity. Although with all three filters an adequate blood flow was usually obtained, the resistance to blood flow was 2-3 times greater than the predicted value. With continued use of the filter, resistance to blood flow remained largely unchanged. When, in the laboratory, the AN-69 capillary filter was perfused with saline and with a viscous sucrose solution, the resistance to flow was only 1.4 time the predicted value, a difference that might result from small deviations of the capillary diameter. When perfused with blood, the resistance was 2.6 times greater than the predicted value. This was largely explained by gross underestimation of blood viscosity in these patients. By combining laboratory data on filter resistance during saline perfusion and a more accurate estimation of blood viscosity, a reasonably accurate prediction of blood flow rate would be feasible. In the clinic the hydraulic permeability of the filters decreased with time.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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10.
Lipid peroxidation, erythrocyte superoxide-dismutase activity and trace metals in young male footballers 总被引:6,自引:0,他引:6
Metin G Atukeren P Alturfan AA Gulyasar T Kaya M Gumustas MK 《Yonsei medical journal》2003,44(6):979-986
Physical training is known to induce oxidative stress in individuals subjected to intense exercise. In this study, we investigated plasma malondialdehyde (MDA) levels and erythrocyte superoxide dismutase (SOD) activity of 25 young male footballers and a control group of similar age. Red blood cell (RBC) count, haemoglobin (Hb) and haematocrit (Hct) values, and copper (Cu) and zinc (Zn) levels were also examined. The maximal oxygen uptake (VO2max) of all subjects was determined in order to establish their functional capacity. The main finding of the present study was that plasma MDA levels, one of the most commonly used markers of lipid peroxidation, of this group of footballers aged under 21 decreased slightly when compared with those of the control group (p < 0.001). In contrast, erythrocyte SOD activity was higher in the footballer group than in the controls (p < 0.001). Footballers who are under regular training showed an improved antioxidant activity in comparison to sedentary controls. Plasma copper concentration, RBC count and Hb concentration of the footballer group were all significantly lower than those of the control group, (p < 0.001, p < 0.01, p < 0.01, respectively). Investigating the footballers' data with Spearman's correlation analyses, the correlation coefficients (r) between Zn/Cu ratio and SOD was positive (r=0.44; p < 0.05); and between VO2max and SOD (r=0.42; p < 0.05) were both positive. On the basis of statistical analysis, we suggest that regular exercise may be beneficial in cases of oxidative damage by reducing the amount of lipid peroxidation and increasing the activity of the antioxidant enzyme SOD. 相似文献