远端半针Ilizarov外固定器结合微创截骨术治疗膝内翻畸形

 目的 探讨远端半针Ilizarov外固定器结合微创截骨术矫治膝内翻畸形的临床疗效。方法 回顾性分析2002年2月至2010年5月收治的31例膝内翻畸形患者的病例,男8例,女23例;年龄18~69岁,平均35.6岁;单侧6例,双侧25例,共56膝。术前膝内翻角度为7.7°~38.2°,平均17.0°±8.8°。根据美国膝关节关节协会评分（knee society score, KSS）为34~100分,平均（86.2±18.5）分。确定成角旋转中心与截骨矫形的位置,在胫骨畸形交点处用微创截骨器截骨,腓骨在头下截骨。安装术前已组装好的Ilizarov外固定器,通过调整伸缩内、外侧支架螺杆的长度渐进矫正内翻畸形。采用X线检查及膝关节KSS临床评分,结合行走时自我感觉及有无并发症等4项内容综合评价临床疗效。结果 患者佩戴Ilizarov外固定器的时间为9~20周,平均12周;随访时间14~50.4个月,平均30.5个月。末次随访时膝内翻角度为-3°~2.4°,平均1.7°±0.9°;膝关节KSS评分为75~100分,平均（96.1±7.7）分,其中优49例,良6例,可1例,优良率为98.2%（55/56）。11例患者术后早期发生轻度针道感染,经常规换药后感染控制;3例术后发生针道松动,经更换针道后恢复固定强度。结论 远端半针Ilizarov外固定器结合微创截骨术矫治膝内翻畸形具有微创、安全、动态矫形及符合美学要求的特点,临床效果满意。     

Ilizarov技术治疗创伤性膝关节屈曲挛缩畸形

 目的 探讨采用Ilizarov 技术治疗创伤性膝关节屈曲挛缩畸形的疗效。 方法回顾性分 析 2006 年1 月至2010 年12 月采用Ilizarov 技术治疗6 例创伤后膝关节屈曲挛缩畸形男性患者的资料, 年龄9~43 岁, 平均24.5 岁;术前膝关节屈曲畸形35°~85°, 平均47.6°;膝关节活动度0°~70°, 平均 15.8°。其中5 例为膝关节陈旧性骨折伴马蹄足畸形, 畸形角度为25°~37°, 平均31.8°;1 例为股骨髁上骨 折。采用环型外固定架逐渐矫正屈膝和马蹄足畸形, 其中4 例因膝关节骨性结构严重破坏且软组织条 件差, 在膝关节恢复伸直位后行膝关节融合术;另2 例膝关节恢复伸直位后, 白天松开螺母活动膝关 节, 睡觉时将膝关节固定在伸直位, 1 个月后去除外固定架改长腿支具保护3 个月。 结果 术后随访 12~22个月, 平均18 个月。6 例患者膝关节屈曲角度由术前47.67°±18.63°恢复到屈曲9.33°±3.50°。5 例 伴马蹄足畸形患者踝关节跖屈角度由术前31.80°±4.65°恢复到术后3.00°±4.47°。4 例患者术后膝关节成 功融合, 2 例膝关节活动度分别为30°和75°。术后6 例患者均可拄手杖行走。术后2~4 个月, 4 例患者出 现针道感染, 经口服抗生素及使用双氧水清洁针道后约2 周感染控制。 结论 采用Ilizarov 技术可有效 治疗创伤后膝关节屈曲畸形。对膝关节骨性结构损伤且软组织条件较差的患者可行膝关节融合术。     

腓骨截骨与运动疗法联合治疗内翻型膝骨关节炎效果分析

目的探讨腓骨截骨与运动疗法联合治疗内翻型膝骨性关节炎的疗效评估。 方法回顾性收集2016年1月至2018年1月岳阳市中心医院骨关节科，采用腓骨截骨与运动疗法治疗膝骨性关节炎伴内翻膝的患者30例，男性5例，女性25例，平均年龄（62±7）岁。于术后4个月、8个月进行随访比较术前及术后的疼痛视觉模拟评分（VAS）、美国特种外科医院（HSS）膝关节评分，膝关节步态改变。 结果30例患者获得随访，随访时间（1.4±0.3）年。HSS评分由术前（50.2±7.8）分增至术后4个月（78.2±6.3）分，术后8个月（82.1±5.5）分；VAS评分由术前（6.8±1.2）分降至术后4个月（3.2±1.1）分，术后8个月（2.5±0.8）分。术后2次随访HSS评分均明显升高、VAS评分均显著降低（P<0.05）。关节角度参数术前屈伸角度-5°~45°，内外翻转角度-8°~18°，内外旋转角度-5°~20°；8个月时屈伸角度-4°~58°，内外翻转角度-7°~13°，内外旋转角度-3°~10°。术后随访发现膝关节屈伸、内外翻、内外旋各角度与正常相比逐步改善，具有统计学意义（P<0.05）。 结论腓骨截骨与运动疗法治疗膝骨性关节炎伴内翻膝早期疗效满意，应用步态分析得出的量化指标为骨性关节炎的诊治及评估提供客观依据,值得临床应用及参考。     

Ilizarov技术矫治复杂僵硬性马蹄内翻足

 目的 探讨Ilizarov技术矫治复杂僵硬性马蹄内翻足的临床疗效。方法 回顾性分析2005年7月至2011年7月28例（41足）僵硬性马蹄内翻足患者的病例,男18例（26足）,女10例（15足）;年龄3~45岁,平均15.3岁;左足8例,右足7例,双足13例。根据Diméglio畸形分级：Ⅲ级31足,Ⅳ级10足。23足采用有限软组织松解、18足配合有限截骨后均安装Ilizarov外固定牵伸器。比较术前及末次随访时踝关节跖屈及背伸角度、踝关节活动度、正侧位X线片上患足距跟角的变化。结果 28例患者均获得随访,随访时间5~38个月,平均25个月。术后外固定支架佩戴2~14个月,平均5.1个月;去除支架后所有患足均获跖行步态,外形接近正常,无足短缩。足背伸角度：术前-45.0°±12.0°,末次随访9.5°±5.5°;跖屈角度：术前67.0°±14.0°,末次随访45.5°±7.8°;正、侧位X线片距跟角：术前分别为6.5°±4.5°和5.5°±11.0°,末次随访分别为22.5°±5.5°和40.6°±8.5°。1足术后发生急性血管痉挛性缺血,予减缓牵伸速度后缓解;5足发生针道感染,予更换针道及换药后感染控制。去支架后3个月,1足出现畸形复发,予二次矫形;3足畸形残留,5足趾屈曲挛缩,均给予二次软组织矫形术,未再复发。结论 Ilizarov技术矫治复杂僵硬性马蹄内翻足疗效确切,能最大程度保留足外形和功能,避免足短缩,不影响足发育。     

伸直位骨性强直膝的全膝关节置换术

 目的 探讨伸直位骨性强直膝全膝关节置换术的手术方法与临床疗效。方法 2000 年6月至2007 年6 月, 对10 例伸直位骨性强直膝患者施行全膝关节置换术。男4 例, 女6 例;年龄29~63岁, 平均49 岁。双膝关节置换2 例, 单膝关节置换8 例。强直性脊柱炎3 例, 类风湿关节炎2 例, 血友病性关节炎1 例, 创伤性关节炎3 例, 化脓性关节炎1 例。膝关节均处于伸直位骨性强直畸形, 活动度0°, 美国特种外科医院(the Hospital for Special Surgery, HSS)膝关节评分(32.5±10.26)分。结果 全部病例随访3~10 年, 平均5.3 年。末次随访时HSS 膝关节评分提高至(87.75±6.45)分, 与术前比较差异有统计学意义(t=18.668, P=0.000)。关节活动度提高至97.08°±11.57°, 与术前比较差异有统计学意义(t=29.063, P=0.000)。术后发生皮肤坏死2 例、下肢深静脉栓塞1 例、假体周围骨折1 例、假体深部感染翻修1 例。术后X线复查未见假体松动。结论 采用髌旁内侧入路、股四头肌切开、二次截骨加软组织松解的全膝关节置换术可矫正伸直位骨性强直膝关节畸形, 配合正确的康复锻炼, 患者的膝关节功能和生活质量能得到明显提高。     

Ilizarov外固定器治疗肥大性骨不连

 目的 探讨采用Ilizarov外固定器治疗肥大性骨不连的疗效。方法 回顾性分析2008年6月至2010年12月,采用Ilizarov环型外固定器直接牵张治疗肥大性骨不连患者的病例,男10例,女2例;年龄22～62岁,平均46.5岁;肱骨中段1例,股骨髁上2例,胫骨中段3例,胫骨中下1/3交界处6例;患肢畸形成角10°～35°,平均25°,其中2例为双平面畸形,10例为单平面畸形;肢体短缩2～6 cm,平均3.5 cm。所有患者术前均拍摄双下肢全长X线片。对骨断端尽量不切开,局部不植骨,直接安装预构的Ilizarov外固定器。对局部留存内固定物者,采用微创的方法取出,尽量保护骨断端血供。术后第7天开始进行矫形延长,断端处每天延长0.25 mm。在恢复肢体长度的同时,矫正成角畸形,对双平面畸形,先矫正冠状面畸形,再矫正矢状面畸形。结果 12例骨不连患者均通过断端直接牵张成骨而获得骨性愈合, 骨断端无需植骨。骨性愈合时间6～12个月,平均8个月。成角畸形和肢体不等长全部获得矫正。畸形矫正时间15～35 d,平均24 d。畸形矫正10°～30°,平均23°。患肢延长2.0～5.5 cm,平均3.0 cm。随访6～18个月,平均14个月,所有患者获得的矫形均未丢失。结论 肥大性骨不连断端间纤维骨痂有活跃的成骨潜能,采用Ilizarov外固定器治疗肥大性骨不连可取得满意的疗效。     

标准型股骨髁、胫骨托与高切迹胫骨聚乙烯垫组合TKA治疗严重膝关节骨性关节炎并膝内、外翻畸形

目的探讨采用标准型股骨髁、胫骨托与高切迹胫骨聚乙烯垫组合全膝关节置换术（TKA）治疗严重膝关节骨性关节炎并膝内、外翻畸形的临床疗效。方法采用标准型股骨髁、胫骨托与高切迹胫骨聚乙烯垫组合TKA治疗20例（25膝）严重膝关节骨性关节炎并膝内、外翻畸形,其中2例保留后交叉韧带,18例不保留后交叉韧带。结果本组20例术后获得平均12（5~60）个月随访。术前膝关节活动范围15°~85°,术后0°~130°。膝内、外翻畸形得到矫正。术前KSS评分（11.50±1.61）分,术后（91.35±1.23）分。结论采用标准型股骨髁、胫骨托与高切迹胫骨聚乙烯垫组合TKA治疗严重膝关节骨性关节炎并膝内、外翻畸形术中通过软组织平衡技术的应用,操作方便,假体稳定性及关节活动度好。早期临床疗效满意,远期疗效有待进一步随访观察。     

组合式外固定器治疗合并患肢短缩的足踝部畸形

背景：传统的足踝部畸形的矫正需要通过手术来完成,术后需要“静态”的维持。Ilizarov技术遵循的“张力-应力法则”和“牵拉组织再生技术”,在一定程度上打破了传统的矫形模式。目的：探讨Ilizarov技术治疗合并患肢短缩的足踝部畸形的临床疗效。方法：回顾分析2006年8月至2012年10月采用Ilizarov技术治疗的17例下肢及足踝部畸形患者的临床资料。其中男10例,女7例,年龄20~37岁,平均27.5岁。脊髓灰质炎后遗症导致患肢短缩合并足踝负重位外翻畸形患者5例,先天性马蹄内翻足合并患肢短缩7例,高弓足合并患肢短缩3例,跟腱挛缩、仰趾畸形合并患肢短缩2例。所有患者在有限手术重建足踝部软组织平衡或者截骨矫正畸形后安装Ilizarov组合式外固定支架,同时做胫骨的延长。结果：17例患者佩戴Ilizarov支架的时间是16~44周,足踝部矫形支架在3~6个月矫形满意、骨融合确实后单独拆除,骨延长支架根据需要继续佩戴。所有患者都获得随访,随访时间6~48个月,患肢延长2~6 cm,延长段骨矿化满意,足踝部矫形满意。足踝功能参照AOFAS评分：术前（43±5.1）分,术后（76±7.2）分。结论：对于各种原因导致的合并下肢短缩的足踝部畸形的矫治,Ilizarov技术灵活的器械组合可同时完成多方向的畸形矫正,在矫正畸形的同时实施骨延长术。     

Ilizarov技术结合矫形支具治疗复杂膝关节畸形的临床研究

[目的]研究、探讨在矫治膝关节畸形中,矫形支具与Ilizarov外固定器结合方法、优点与临床疗效.[方法] 2005年5月～ 2012年12月本科采用Ilizarov技术结合矫形支具治疗膝关节畸形患者36例36膝,其中男23例,女13例,左20例,右16例;年龄6～56岁,平均28岁;脊髓灰质炎后遗症膝反屈畸形17例,术中行腘绳肌紧缩后临时用组合式外固定器固定于屈膝20°位,术后2周拆除股骨外固定做大腿支具并用螺纹牵伸杆跨膝关节继续固定;小腿延长致膝关节屈曲畸形10例,直接做大腿支具跨膝关节固定,后侧用螺纹牵伸杆连接,可逐渐矫正屈膝畸形;膝内翻畸形合并外侧副韧带松弛8例,行胫骨截骨矫形,同期行外侧副韧带重建并用组合式外固定器固定膝关节,术后2周拆除股骨外固定改为大腿支具并用螺纹牵伸杆跨膝关节继续固定;血管瘤致屈膝畸形1例,采用股骨外固定器结合小腿支具牵拉矫正屈膝畸形.[结果] 36例患者中,32例获得8～60个月随访,平均19个月,所有膝关节畸形均获满意矫正,下肢负重力线恢复满意,截骨端愈合时间60 ～ 150 d,平均120 d;外固定针道感染5例,经局部换药处理好转;采用HSS评分系统进行评分,优18膝,良10膝,可4膝,优良率为87.5％.[结论]遵循Ilizarov技术原理,采用Ilizarov外固定器联合矫形支具的方法治疗合并有软组织因素的复杂膝关节畸形,可以获得满意的矫形结果及良好的膝关节功能;具有创伤小、固定灵活、制作简单等优点.     

膝关节表面置换术治疗膝关节骨性关节炎合并内翻及屈曲挛缩畸形的疗效分析

目的探讨膝关节骨性关节炎合并屈曲挛缩、内翻畸形患者行膝关节表面置换术中软组织平衡及截骨技术和早期临床疗效。方法笔者自2008-02—2015-05对98例(145膝)膝关节内翻并屈曲挛缩畸形行膝关节表面置换术,通过分析患者术前畸形程度、术中截骨和软组织松解情况、术后畸形矫正程度和膝关节功能恢复的情况。结果术后内翻矫正136膝,仍有内翻残留9膝(3°~6°);膝关节活动度:伸直0°121膝,伸直受限10°18膝,11°~15°4膝;膝关节屈曲度数90°~120°,HSS评分78~94分,临床及X线片检查未见明显松动迹象。结论膝关节表面置换术治疗晚期膝关节骨性关节炎合并屈曲挛缩、膝内翻畸形是目前临床疗效较好的方法。术中准确截骨和正确的软组织平衡以及合理的术后康复锻炼是矫正膝关节内翻和屈曲挛缩畸形的关键。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.