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991.
Internal fixation of children's fractures of the lower extremity   总被引:1,自引:0,他引:1  
Lower grade fractures are by definition stable and almost always treated with casting or functional splinting. The best kind of fixation for the higher grade fractures, however, differs between adults and children. Appropriate treatments are discussed, and case-study illustrations are provided. Background on the anatomy of the tibia and femur is included.  相似文献   
992.
Femoral rotary osteotomies according to Sugioka and A. M. Sokolovsky in adults are mostly indicated in case of idiopathic aseptic necrosis of the femoral head. As an indication for child and adolescent operations can serve multiplanar deformations of the femur proximal end following early treatment of congenital dislocations. Perthes disease, in some cases--pathological femur subluxations as well as juvenile epiphysiolysis. 30 adults and 24 children and adolescents aged 3.5-17 years have been operated on. In the majority of cases good and satisfactory results have been achieved. The peculiarity of the rotary osteotomy technique application in childhood is the severance of the greater trochanter with the zone of growth.  相似文献   
993.
Among diseases due to cerebral parasitism, that caused by Sparganum mansoni, the larva of Spirometra mansoni, is very rare. We have encountered two such cases. A computed tomography scan in both revealed a nodular high density contrast enhanced area against an extensive low density background area. Neither calcification nor cyst formation was recognized. These computed tomography scan findings were thought to be characteristic for cerebral sparganosis mansoni and were difficult to differentiate from those of a cerebral tumor. In both cases, definitive diagnosis was achieved by identification of the worm after excision of the lesion. The best treatment for cerebral sparganosis mansoni is surgical excision of the lesion, and in the two cases presented the postoperative outcome was good.  相似文献   
994.
Leg length equalization during total hip replacement   总被引:9,自引:0,他引:9  
S T Woolson 《Orthopedics》1990,13(1):17-21
A method of equalization of leg lengths during total hip replacement surgery was developed which utilizes the concept of equalizing the vertical dimensions of the resected femoral head and neck segment and the remaining hip joint cartilage space, which are removed during the procedure, with the vertical dimensions of the femoral and acetabular prostheses, which are implanted into that void. This was accomplished by determining the dimensions of the prostheses from careful preoperative templating technique and by using a simple arithmetic formula to determine the level of the femoral neck osteotomy. The level of the osteotomy was made by a measurement from the top of the dislocated head of the femur to the medial femoral neck calcar. The radiologic postoperative leg length differences of a consecutive series of 84 patients undergoing primary total hip replacement using this method were determined. The average discrepancy was 2.8 mm. Seventy-five patients (89%) were found to have a postoperative leg length discrepancy of 6 mm (1/4 inch) or less. Six patients (7%) had a discrepancy of 7 to 13 mm, and only three patients (4%) had more than 13 mm (1/2 inch) leg length difference. Using this technique only two patients (2.5%) with unilateral hip replacements had leg lengthening of more than 6 mm.  相似文献   
995.
996.
The work has analyzed results of 91 transaortal endarterectomies and 66 prostheses of renal arteries with the autovein. A preliminarily arterialized autovein is proposed as an autotransplant. The arterialization is achieved by inclusion of the autovein in the peripheral arterial system where the vein is gradually transformed and within 10-12 weeks its structure and biomechanical properties become closer to those of the artery of the musculo-elastic type. Preliminary arterialization excludes dilatatory changes of the autovenous transport.  相似文献   
997.
A child with unilateral dysplasia of the superior articular facet of the axis is described. This congenital anomaly, due to incomplete ossification, may be a cause of torticollis, although no signs of instability were noted.  相似文献   
998.
Although smoking-cessation rates have continued to increase, the vast majority of smokers who quit eventually relapse. Between 1974 and 1985, over 1.3 million smokers quit during each of those years. However, 75% to 80% of those individuals resumed smoking within six months. This article describes the dynamic phenomenon of smoking relapse within the context of cyclical episodes of smoking and quitting during an individual's lifetime. Theories of the determinants of smoking relapse are reviewed and methods designed to prevent relapse are described. Smoking relapse is discussed in terms of three aspects of tobacco addiction: (1) biological-addiction mechanisms, (2) conditioning processes, and (3) cognitive-social learning factors. The major determinants of smoking relapse are reviewed, including nicotine withdrawal, stress, weight gain, social influences, conditioning factors, causal attributions, and environmental variables. A trans-theoretical-developmental model is explored in the longitudinal investigation of the natural history of slips (lapses) and relapse episodes. Relapse prevention interventions are described that emphasize self-awareness, self-regulation, self-efficacy, affect regulation, social support, and lifestyle balance. Recent developments in pharmacological adjuncts to treatment are also examined. It is concluded that innovative relapse prevention methods need to be designed for hard-core smokers with histories of cessation failures, substance abuse and/or psychiatric impairment. These and other recommendations for future research on smoking relapse and relapse prevention are discussed.  相似文献   
999.
Interindividual variations in the immunosuppressive effect of Cyclosporine have been observed in clinical organ transplantation. Searching for an in vitro correlate we investigated a possible relation between inhibition of alloresponsiveness by CsA and the HLA phenotypes of the responder or stimulator in mixed lymphocyte reactions. Peripheral blood mononuclear cells from 28 healthy volunteers were used as responder or stimulator cells (gamma-irradiated) and the inhibitory effect of graded amounts of CsA was determined in 130 criss-cross combinations. Sensitivity of alloresponsiveness to the drug was expressed as the dose causing 50% inhibition (ED50) and was read from the inhibition curves generated after four-parameter logistic curve fitting. ED50 ranged from 0.35 ng/ml to 33.4 ng/ml and correlated only weakly with the magnitude of the response (r = 0.12). In MLC with HLA DR4-positive responder cells, ED50 was significantly lower (Pc = 0.0035, Kruskal Wallis) when compared with MLC with responder cells of other DR haplotypes. For HLA DR5-positive responder cells ED50 was significantly higher (Pc = 0.042) when compared with DR5-negative responder cells. No significant correlation between ED50 and any particular haplotype of the stimulator cells could be observed. Sensitivity to CSA did not differ in MLC with 1 or 2 mismatches in the HLA-DR locus. In summary, we found that sensitivity of in vitro alloreactivity was different for particular HLA DR phenotypes, which may have important implications for the immunosuppressive therapy of transplanted patients with cyclosporine.  相似文献   
1000.
In fetal rats whose dams were fed a low-protein diet, 35S sulfate uptake into the growth plate of the long bone and rib was higher than in the control group. The elution pattern of guanidine-HCl extract in gel chromatography revealed that the malnourished group had more high molecular weight proteoglycans in the dissociative condition and a larger aggregated portion in the associative condition than did the control group; however, the same chondroitin-sulfate chain size existed. Calcium content did not differ in both groups. Aggregated proteoglycan or a high molecular weight proteoglycan that existed in the malnourished group probably played an inhibitory role in calcification. Prenatal protein-energy malnutrition may delay the change of proteoglycan character, which could affect mineralization of fetal bones.  相似文献   
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