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991.
颈椎前路手术后邻近节段运动变化的生物力学研究 总被引:6,自引:0,他引:6
目的利用压敏片(PSF)技术,测量颈椎前路手术后关节突关节内压力的变化,探讨颈前路手术后远期邻近节段退变的生物力学发病机制。方法10具新鲜成人颈椎尸体标本(C2~T1),行前路C4,5椎间盘切除、C4,5椎间植骨钢板内固定术。将压敏片置于关节突关节内,在脊柱三维运动试验机上测量0载荷和2N·m载荷下,后伸、左右侧弯、左右旋转过程中关节突关节内压力的变化。结果颈椎前路手术后,邻近节段关节突关节内的压力增加,以后伸和左右旋转时最为明显,差异有显著性意义(P<0.05)。结论颈椎前路短节段植骨融合术后,邻近节段关节突关节内压力明显增加,可诱发邻近节段关节突关节的退变,从而引起相应的病症。 相似文献
992.
N.D. Stafford L.T. Condon M.J.C. Rogers A.W. MacDonald S.L. Atkin 《Clinical otolaryngology》2003,28(4):314-319
The expression of somatostatin receptors 1 and 2 in benign, pre‐malignant and malignant laryngeal lesions The role of chemotherapy in squamous cell carcinoma of the larynx has not been clearly defined. Whilst toxic chemotherapy regimes may confer a marginal improvement in survival, surgery and radiotherapy remain the mainstay of treatment. Somatostatin is a naturally occurring peptide, which exerts antiproliferative and antiangiogenic effects via five membrane‐bound receptor subtypes. The expression of somatostatin receptor subtypes (SSTRs) 1 and 2 was studied in benign, pre‐malignant and malignant laryngeal specimens. Epithelial expression of SSTR1 was detected in 4/6 (67%) Reinke's oedema, 5/6 (83%) pre‐malignant and 8/12 (67%) malignant specimens, with virtually no stromal or vascular expression. High levels of epithelial SSTR2 expression were noted in all Reinke's oedema specimens, compared with low‐to‐moderate levels in only 2/6 (33%) pre‐malignant and 3/12 (25%) malignant specimens (P < 0.01). This ‘loss’ of epithelial SSTR2 expression may provide a growth advantage in pre‐malignant and malignant laryngeal lesions. Vascular expression of SSTR2 was ubiquitous in all groups, with scant stromal expression. Overall, most (>80%) pre‐malignant and malignant laryngeal specimens expressed at least one of the two SSTR subtypes studied. Somatostatin analogues may have a therapeutic role in squamous cell carcinoma of the larynx. 相似文献
993.
Fred Poordad Robert Gish Adil Wakil Richard Garcia-Kennedy Paul Martin Francis Y. Yao 《American journal of transplantation》2003,3(11):1413-1417
Non-alcoholic fatty liver disease (NAFLD) is an increasingly recognized clinico-pathologic entity typically associated with obesity, type II diabetes and hyperlipidemia. It has been noted to recur after orthotopic liver transplantation (OLT). We report four patients who developed de novo NAFLD within 3 months of OLT without the typical predisposing factors of diabetes mellitus or obesity. Three of the four patients underwent OLT for hepatitis C-related cirrhosis, and the other for alcoholic cirrhosis. Examination of the liver explants revealed no evidence of steatosis. No surreptitious alcohol use or a drug-induced process could be identified in these patients. Treatment of recurrent hepatitis C infection in one patient with interferon and ribavirin led to sustained suppression of the viral RNA to undetectable levels, but no improvement in histology or liver enzymes. All four patients had histologic evidence of preservation injury on the initial post-OLT biopsies, but the significance of this finding in relationship to the development of NAFLD is unknown. NAFLD can develop without any of the known predisposing conditions after transplantation, and this raises further questions about the pathogenesis of this condition . 相似文献
994.
995.
Joseph I. Pascal 《American journal of ophthalmology》1948,31(10):1330-1331
996.
997.
Phrabhakaran Nambiar Norliza Ibrahim Yeti Rosalina Muslim Tandjung P. Shanmuhasuntharam 《Oral Radiology》2008,24(1):10-15
Objectives We conducted a study to determine the numbers of susuks (charm needles) and their distribution in the craniofacial region of susuk wearers, and the sex, racial affiliation, and age of the wearers. In addition, we sought to determine whether the presence
of susuks posed any potential hazard to patients undergoing magnetic resonance imaging (MRI).
Methods We studied various radiographs of 33 susuk wearers (age range, 33–69 years) and investigated the most common sites of insertion in the craniofacial region. A susuk was also suspended inside a 1.5-T MRI machine to determined whether it was attracted by the machine’s magnet.
Results The largest number of susuks that we observed in the craniofacial region was 39 pins, and susuks were particularly numerous in Malay Muslim women. Other sites with susuks were the maxillofacial region (except the temporomandibular region) and the forehead. The susuks showed no ferromagnetic characteristics.
Conclusions As susuks are made from gold, they are generally biocompatible with human tissue and do not cause problems to their wearers. Gold and
the other minor metal constituents found in susuks have no ferromagnetic characteristics and therefore pose no hazard to patients undergoing MRI. 相似文献
998.
Taking advantage of two large, population-based, and longitudinal datasets collected after the 1999 floods in Mexico (n = 561) and the September 11, 2001 terrorist attacks in New York (n = 1267), we examined the notion that resilience may be best understood and measured as one member of a set of trajectories that may follow exposure to trauma or severe stress. We hypothesized that resistance, resilience, recovery, relapsing/remitting, delayed dysfunction, and chronic dysfunction trajectories were all possible in the aftermath of major disasters. Semi-parametric group-based modeling yielded the strongest evidence for resistance (no or mild and stable symptoms), resilience (initially moderate or severe symptoms followed by a sharp decrease), recovery (initially moderate or severe symptoms followed by a gradual decrease), and chronic dysfunction (moderate or severe and stable symptoms), as these trajectories were prevalent in both samples. Neither Mexico nor New York showed a relapsing/remitting trajectory, and only New York showed a delayed dysfunction trajectory. Understanding patterns of psychological distress over time may present opportunities for interventions that aim to increase resilience, and decrease more adverse trajectories, after mass traumatic events. 相似文献
999.
目的:观察阿托伐他汀对系膜增殖性肾炎(MsPGN)大鼠肾组织细胞外基质(ECM)和纤溶酶原激活剂抑制物-1(PAI-1)表达的影响,探讨其肾脏保护作用的机制。方法:采用抗胸腺细胞血清诱发的MsPGN大鼠模型,将SD大鼠随机分为正常对照组、肾炎模型组、小剂量阿托伐他汀治疗组(8mg·kg^-1·d^-1)和大剂量阿托伐他汀治疗组(16mg·kg^-1·d^-1)。治疗12d后。检测各组大鼠血总胆固醇(CHOL)、甘油三酯(TG)、血肌酐(Scr)和24h尿蛋白,以及肾组织Ⅳ型胶原(Col Ⅳ)、纤维结合蛋白(FN)和PAI-1的表达。结果:阿托伐他汀治疗组大鼠24h尿蛋白、肾组织Col Ⅳ、FN和PAI-1 mRNA的表达明显下降。肾组织病理改变明显改善,与模型组相比有统计学差异(P〈0.05),且呈剂量依赖关系。其中肾炎模型组尿蛋白(30.34±0.62)mg/d。阿托伐他汀小剂量治疗组(21.17±0.79)mg/d,大剂量治疗组(9.77±0.54)mg/d。同时,各组血脂水平无明显差异(P〉0.05)。结论:阿托伐他汀可显著改善MsPGN大鼠肾脏病变,抑制肾组织ECM成分和PAI-1的表达。 相似文献
1000.
计算机辅助精液分析男性不育患者精子运动参数与精子活力的相关性 总被引:2,自引:1,他引:1
目的探讨计算机辅助精液分析精子运动参数在评价男性不育患者精子活力中的价值。方法按《WHO人类精液及精子-宫颈黏液相互作用实验检验手册》标准,采用国产WLJY-9000伟力彩色精子质量检测系统对276例男性不育患者的精液进行平均直线运动速度、平均曲线运动速度、运动的前向性、运动的直线性、运动的摆动性、平均路径速度、精子活力及分级等进行检测并分析其相关性。结果276名男性不育患者的平均精子活力为(48.93±19.10)%,分级为A级(32.11±17.25)%、B级(17.03±8.91)%、C级(10.14±5.99)%。平均直线运动速度、平均曲线运动速度、运动的前向性、运动的直线性、运动的摆动性、平均路径速度与精子活力的相关系数分别为0.60(P〈0.01)、0.59(P〈0.01)、0.51(P〈0.01)、0.55(P〈0.01)、0.52(P〈0.01)、0.67(P〈0.01)。结论计算机辅助精液分析精子运动参数平均直线运动速度、平均曲线运动速度、平均路径速度是反映精子活力的有效指标,精子运动参数对男性不育的诊断和生育能力的评估具有实用意义。 相似文献