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41.
The anteversion angle of femoral neck in 40 children, aged 18 months to 14 years (4.6 years on average), with congenital dislocation of hip was measured pre-operatively on X-ray films according to the way of Dr. Hu's method, and from the proximal femur exposed during operation. The mean value of them was 64.6 degrees and 44 degrees respectively, being statistically significant (P less than 0.01). The method of direct measurement of the anteversion angle during operation was described. The factors affecting the diversity of the measured angle value with different methods were discussed. It seems that the calculation formula used in Hu's method should somehow be corrected and a revision is put forward. 相似文献
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Lei Wang Moyi Sun Yuegui Jiang Lianjia Yang Delin Lei Chao Lu Yinghua Zhao Pu Zhang Yaowu Yang Jianhu Li 《Journal of oral and maxillofacial surgery》2006,64(4):636-641
PURPOSE: Perineural invasion is a frequent occurrence in salivary adenoid cystic carcinoma (ACC) and may prevent complete surgical resection. Studies have indicated that nerve growth factor (NGF) and its high-affinity receptor tyrosine kinase A (TrkA) may play a role in perineural invasion in several malignancies in which perineural invasion is observed. The present study was conducted to investigate the expression of NGF and TrkA in salivary ACC and to examine the effects of NGF on adhesion, migration and invasion capacities of a salivary ACC cell line (SACC-83) in vitro. PATIENTS AND METHODS: Expression of NGF and TrkA was explored using immunohistochemistry in paraffin-embedded tissues of 32 cases of salivary ACC. The effects of NGF on in vitro adhesion, migration, and invasion capacities of the SACC-83 cell line were examined using an MTT assay and a modified Boyden chamber assay respectively. RESULTS: In ACC specimens, 31 (96.9%) and 32 (100%) tumors showed immunoreactivity for NGF and TrkA respectively. Significant correlations were found between NGF/TrkA expression levels and perineural invasion (P < .05). In cell adhesion assay, the percent adherences of SACC-83 cells co-cultured with 25 ng/ml NGF at 1.5 hours and 5, 25 ng/ml NGF at 6 hours were significantly higher than that co-cultured with 0 ng/ml NGF (P < .05). However, high concentration of NGF (500 ng/ml) resulted in a significant inhibition of invasion (P < .05). CONCLUSION: Overexpression of NGF and TrkA in human salivary ACC tissues may constitute a reason for perineural invasion in salivary ACC. 相似文献
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A new axial skin flap based on the middle cutaneous branch of the medial plantar artery was evaluated in 33 fresh cadaver legs. The vascular pedicle of the skin flap is based on the middle cutaneous artery, its venae comitantes, and segments of the great saphenous vein, if necessary. The middle cutaneous artery is the largest cutaneous branch, arising from the medial plantar artery 2.5 cm distal to its origin. The diameter of its origin is 1.2 mm, and its pedicle is 2 cm long. The midline of the flap runs from the first web space to the heel tip. The upper and lower borders of the flap are 3 to 4 cm on either side of this line. The upper border is medial to the extensor hallucis tendon, and the lower border is medial to the abductor hallucis. Distally, the border begins 2 cm proximal to the metatarsalphalangeal joint; proximally, the border is at the middle of the medial malleolus. The flap diameter can be up to 8 × 12 cm. The middle cutaneous branch of the medial plantar artery was found in all cadaver specimens, except for one with a common trunk. The new flap design leaves the major blood supply to the foot and the plantar aponeurosis intact. It is easy to harvest and may be used either as an island flap or free flap. © 1995 Wiley-Liss, Inc. 相似文献
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The levels of SO2, NOx and CO to which each population group living in Kun District of Baotou City was exposed 总被引:2,自引:0,他引:2
Y X Zhang 《中华预防医学杂志》1988,22(3):152-156
48.
神经肽Y(NPY)是广泛分布于中枢神经系统和外周神经各部位的神经肽类物质。本实验观察NPY在体外对几种免疫细胞活性的直接作用。结果表明,NPY对小鼠T淋巴细胞丝裂原反应性和NK细胞的杀伤活性均无明显影响(P>0.05),对巨噬细胞分泌溶菌酶有明显抑制作用(P<0.05);而对B淋巴细胞丝裂原反应性则有明显的促进作用(P<0.05)。上述结果提示,NPY对部分免疫细胞功能的影响因细胞种类而异。 相似文献
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