我国医疗器械数字化技术发展中存在的主要问题及原因

本文提出了我国医疗器械产业中数字化技术发展中存在的主要问题，并分析了问题产生的原因。     

Magnetic Resonance Imaging of the Breast: Current Practice and Future Developments

Over the past decade, there has been a dramatic increase in the use of magnetic resonance imaging (MRI) of the breast. MRI has proven to be a key tool in the detection and diagnosis of breast cancer and it plays a very important role in the evaluation of response to therapy. Breast MRI is highly sensitive and is able to detect lesions, which are occult on mammography and ultrasound. With the introduction of contrast agents, advances in surface coil technology and focused work in optimal scan protocols, breast MRI has continued to evolve as a valuable adjunctive breast imaging tool. This review will give a summary of current criteria and techniques that may be used in the detection, diagnosis and excision of breast lesions.     

Screw angulation affects bone-screw stresses and bone graft load sharing in anterior cervical corpectomy fusion with a rigid screw-plate construct: a finite element model study

Background contextAnterior corpectomy and reconstruction with bone graft and a rigid screw-plate construct is an established procedure for treatment of cervical neural compression. Despite its reliability in relieving symptoms, there is a high rate of construct failure, especially in multilevel cases.PurposeThere has been no study evaluating the biomechanical effects of screw angulation on construct stability; this study investigates the C4–C7 construct stability and load-sharing properties among varying screw angulations in a rigid plate-screw construct.Study designA finite element model of a two-level cervical corpectomy with static anterior cervical plate.MethodsA three-dimensional finite element (FE) model of an intact C3–T1 segment was developed and validated. From this intact model, a fusion model (two-level [C5, C6] anterior corpectomy) was developed and validated. After corpectomy, allograft interbody fusion with a rigid anterior screw-plate construct was created from C4 to C7. Five additional FE models were developed from the fusion model corresponding to five different combinations of screw angulations within the vertebral bodies (C4, C7): (0°, 0°), (5°, 5°), (10°, 10°), (15°, 15°), and (15°, 0°). The fifth fusion model was termed as a hybrid fusion model.ResultsThe stability of a two-level corpectomy reconstruction is not dependent on the position of the screws. Despite the locked screw-plate interface, some degree of load sharing is transmitted to the graft. The load seen by the graft and the shear stress at the bone-screw junction is dependent on the angle of the screws with respect to the end plate. Higher stresses are seen at more divergent angles, particularly at the lower level of the construct.ConclusionThis study suggests that screw divergence from the end plates not only increases load transmission to the graft but also predisposes the screws to higher shear forces after corpectomy reconstruction. In particular, the inferior screw demonstrated larger stress than the upper-level screws. In the proposed hybrid fusion model, lower stresses on the bone graft, end plates, and bone-screw interface were recorded, inferring lower construct failure (end-plate fractures and screw pullout) potential at the inferior construct end.     

后腹腔镜治疗肾上腺肿瘤35例临床分析

目的总结后腹腔镜技术治疗肾上腺肿瘤的临床经验.方法采用后腹腔镜切除肾上腺肿瘤35例,男12例,女23例.年龄25岁～72岁,平均49.8岁.左侧15例,右侧20例.其中嗜铬细胞瘤5例,原发性醛固酮增多症10,柯兴氏病2例,神经节细胞瘤2例,无功能性腺瘤16例.腰部取3个套管针穿刺入路,用自制的水囊扩张器扩张后腹腔,用超声刀将肿瘤切除.结果 35例手术均成功,无中转开放手术病例.术中出血量10～500 ml,平均74 ml.病人均未输血.手术时间45～200 min,平均90 min.结论后腹腔镜手术切除肾上腺肿瘤手术效果确切,手术时间短,术中出血少,损伤小,术后恢复快,可以替代绝大多数肾上腺肿瘤开放手术.     

Brain natriuretic peptide enhances the endothelium-independent cAMP and vasorelaxant responses of calcitonin gene-related peptide in rat aorta

Calcitonin gene-related peptide (CGRP) causes vasorelaxation in rat aorta involving endothelium/nitric oxide (NO)-dependent elevations of both cAMP and cGMP levels. When endothelium is removed, preincubation with exogenous NO uncovers and potentiates direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP. This enhancing effect of NO potentially involves elevation of cGMP and inhibition of Type III (cGMPinhibitable) phosphodiesterase, causing accumulation of cAMP. However, NO may have other actions. The aim of the present study was to determine if brain natriuretic peptide (BNP), which elevates cGMP levels independent of NO, could enhance cAMP accumulations and vasorelaxations induced by CGRP in rat aortic rings denuded of endothelium. When added separately, neither CGRP (100 nM) nor BNP (10 nM) altered cAMP levels. When added in combination, CGRP (100 nM) and BNP (10 nM) significantly elevated cAMP levels (from control of 0.95 ± 0.08 to 1.53 ± 0.09 pmol/mg protein) at 2 min. BNP (10 nM) elevated cGMP levels 10-fold at 2 min and this response was not altered by co-administration of CGRP (100 nM).Pretreatment with BNP at concentrations as low as 1 nM in endothelium-denuded aortic rings greatly enhanced the direct vasorelaxant effects of CGRP (100 nM) (from control of 0% to 57.6 ± 6.8% relaxation of phenylephrineprecontractions). Our findings indicate that BNP enhances direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP in rat aorta, thus supporting the concept that cGMP inhibits cAMP metabolism and enhances CGRP-induced responses in aortic smooth muscle cells.     

Cardiokymograph system with a capacitance transducer and its preliminary application in the measurement of heart wall movement

A novel cardiokymograph system is introduced. The new system features a capacitance transducer with increased sensitivity and can be used in multichannel measurements. The novelty of this technique is the injection of a current into the patient coupled with the use of a capacitive displacement transducer and the possibility of multichannel monitoring. It provides for the possibility of removing breath noise when some signal processing technique, such as adaptive filtering, is used. Further investigation is needed to demonstrate clinical significance and pathologies.     

帕金森病相关致病基因的研究进展

近年来，帕金森病(PD)的遗传学研究取得了较大的进展，迄今为止已经确定了PARK1-PARK10等10个单基因与PD的发生有关。其中三个基因产物与家族性PD有关，它们分别是a-synuclein(PARK1)、parkin(PARK2)和泛素蛋白C末端羟化酶-L1(PARK5)，它们均参与Lewy小体．的形成，在PD的发病过程中扮演重要的角色。虽然另外几个基因对应的蛋白或对应蛋白的功能未知，但已经在染色体上找到相应的位置。PD遗传学的研究将有助于PD的早期诊断．并且有可能为PD的治疗提供新的靶点。本文概述了PD相关基因的最新研究进展。     

肾动脉狭窄支架植入术的临床疗效观察

目的探讨肾动脉狭窄支架植入术的临床疗效.方法1997年1月～2004年12月,我院行支架介入治疗肾动脉狭窄27例.对27例术前、术后及随访期内血压、肾功能以及生活质量进行评估,并与同期单纯药物治疗肾动脉狭窄27例进行比较.结果介入组27例植入支架40枚,手术成功24例(88.9%,24/27),失败3例(11.1%,3/27),手术并发症5例(18.5%,5/27).术后在血压下降(包括收缩压舒张压)肌酐下降,肾小球滤过率增加方面,介入组获益率明显优于药物组,两组比较差异均有显著性,术后随访6个月～8年6个月,中位数为1年9个月,介入组有19例能比较健康的生活和工作,药物组仅12例能维持生活和工作.结论支架介入治疗较单纯药物治疗肾动脉狭窄疗效显著.     

明胶降解物对大鼠真皮成纤维细胞增殖及Ⅰ型胶原蛋白分泌的影响

目的 探讨组织工程心瓣膜常用人工基质材料--明胶发生降解后的产物对大鼠真皮成纤维细胞增殖及Ⅰ型胶原蛋白分泌的影响. 方法 利用酶组合技术制备明胶降解物（gelatin hydrolysate, GH）,采用超滤的方法分离出低分子量明胶降解物组分（gelatin hydrolysate fraction, GHF）,用于5只SD大鼠真皮成纤维细胞的体外培养.采用CCK-8活细胞计数试剂盒（Cell Counting Kit-8）检测细胞的增殖情况,ELISA试剂盒检测细胞I型胶原蛋白的分泌情况. 结果 ①GHF对细胞增殖作用的浓度效应：在0.125～1.0 mg/ml浓度范围内,GHF对细胞的促增殖作用呈现先增强后减弱的趋势,在0.25 mg/ml时,细胞增殖率最大,达到（47.54±16.35）%;②GH与GHF对细胞增殖影响比较：GH与GHF均具有促进细胞增殖的作用,且在浓度为0.25 mg/ml时,促细胞增殖作用无显著差异[（27.04±15.21）% vs （39.22±15.55）%, P=0.177];③GH与GHF对细胞分泌Ⅰ型胶原蛋白影响比较：GHF组第3天时Ⅰ型胶原分泌量为（28.06±5.60）pg/105,与空白对照的（18.24±4.52）pg/105相比,有显著差异（P=0.006）,而GH组直至第6天时Ⅰ型胶原蛋白分泌量,与空白对照相比,无统计学意义（P=0.103）. 结论 分子量大小不同的明胶降解物GH与GHF均具有促进大鼠真皮成纤维细胞增殖的作用,且分子量较小的GHF还具有促进细胞I型胶原分泌的功能.