髋臼前柱钢板内固定的解剖学研究

目的研究髋臼前柱钢板内固定技术中螺钉的最佳进钉点、方向和长度,预防发生螺钉穿入关节内的严重并发症。方法取成年男性半骨盆标本20个,分别测量髋臼前、后缘到髂前下棘、髂耻隆起和耻骨结节的距离,确定和制作髋臼前柱系列断面,分别测量各断面上各进钉点的安全进钉角度,将测量数据输入到SPSS10.0软件进行统计学分析。结果髋臼前缘到髂前下棘、髂耻隆起和耻骨结节的距离分别为(25.4±1.4)mm,(11.8±0.7)mm和(37.4±1.5)mm,后缘到髂前下棘和髂耻隆起的距离分别为(15.5±0.9)mm和(29.1±1.6)mm。在各断面距离骨盆界线0.5cm点、1.0cm点和1.5cm点上螺钉的安全进钉角度的最大值分别为(8.2±2.2)°、(14.9±3.4)°和(26.1±4.5)°。结论在前柱髋臼区使用钢板内固定时,可以采用3种方法避免螺钉穿入关节内。第一种方法是使用短螺钉,螺钉方向随意;第二种方法是使用长螺钉紧贴骨盆界线进钉,方向平行于四方区;第三种方法为根据不同的进钉点选择不同的进钉角度和长度。     

髋臼后柱拉力螺钉内固定的临床解剖学研究

目的研究髋臼后柱拉力螺钉内固定螺钉的最佳进钉点、方向和长度。方法取12个骨盆标本,其中男7个,女5个。於双侧髋臼中部垂直于前后柱表面截骨,逆行法沿后柱中心打入一克氏针,其从髂窝的穿出点为P点,作参考线AB,其中A为骶髂关节最前缘,B为髂前下棘基底下缘,由P点向AB作垂线,与AB相交于D点,然后测量以下数值:1.测量AB、AD、PD的距离;2.测量仰卧位时后柱克氏针与水平面的夹角α,与矢状面的夹角β;3.测量髋臼后柱截面的半径;4.测量后柱克氏针在骨皮质内的长度。结果PD是AB的中垂线。PD的距离男性为1.62±0.23cm,女性为1.51±0.10cm;夹角α男性为24.3±2.0°,女性为24.0±1.3°;夹角β男性为25.9±3.1°,女性为14.7±2.0°;后柱截面半径男性为10.18±1.24mm,女性为8.57±0.82mm;后柱克氏针长度男性为11.6±0.8cm,女性为10.2±0.5cm。结论髋臼后柱拉力螺钉内固定是可行的。     

髋臼前柱骨折经皮逆行拉力螺钉固定的三维重建模型研究

目的 探讨髋臼前柱骨折经皮逆行拉力螺钉固定的应用解剖学基础.方法 收集82例164个成人半骨盆CT扫描数据,重建骨盆三维模型.男80个,女84个年龄18～80岁,平均(49.1±18.4)岁.在髋臼前柱置入虚拟三维圆柱体,模拟逆行拉力螺钉固定,计算其最大直径、长度、方向以及置入点(A)到耻骨联合(B)和耻骨上支上缘(C)的垂直距离.在相同的三维重建模型上,垂直髋臼前柱前侧面进行模拟截骨,测量截骨面的直径.找出最小的截骨面,用圆盘法测量其直径.结果 虚拟三维圆柱体的平均最大直径为(8.16±1.21)mm,最大长度为(109.39±8.95)mm,与水平面、冠状面和矢状面的夹角分别为39.66°±3.92°、20.81°±4.58°和42.66°±3.23°,AB和AC的长度分别为(18.42±4.82)mm和(17.76±2.63)mm.虚拟三维圆柱体的最大直径、长度以及AB的长度在男、女之间的差异有统计学意义.截骨面的平均最小直径和最小截骨面的圆盘直径均明显大于虚拟三维圆柱体的平均最大直径.结论 所有男性髋臼前柱可容纳6.5 mm的螺钉,但部分女性无法使用6.5 mm的螺钉,且男、女的进针点不同.螺钉的直径不能仅靠截骨面的直径确定.     

顺行拉力螺钉固定髋臼后柱骨折进钉的解剖学参数研究

目的 探讨顺行拉力螺钉固定髋臼后柱骨折的进钉参数,为进钉瞄准器的研制提供应用解剖学基础.方法 收集40例正常成人(男20例,女20例)骨盆的螺旋CT扫描数据,重建骨盆三维模型.经髂前上棘(A)和髂后上棘(B)的骨性最突出点的连线中点M做一平面(γ)垂直于AB,在髋臼后柱的γ截面上模拟置人虚拟圆柱体,该圆柱体从髂翼内侧的穿出点(O)即为拉力螺钉的入钉点.在弓状缘上取点D,使OD成为入钉点与弓状缘之间的最短距离,连结OD,G点为骶髂关节最前缘,连结DG.测量OD、DG的距离、置入拉力螺钉的长度、拉力螺钉与冠状面的夹角(α)及与矢状面的夹角(β). 结果 OD距离平均为(13.62±2.19)mm,DG距离平均为(15.27±4.01) mm,能置入拉力螺钉的长度平均为(116.65±7.19) mm,α夹角平均为15.47°±4.01°,β夹角平均为6.65°±2.93°.男、女性在DG距离、β夹角、置入拉力螺钉的长度方面差异均有统计学意义(P＜0.05),而在OD距离及α夹角方面差异均无统计学意义(P＞0.05). 结论 根据髋臼后柱顺行拉力螺钉置钉的解剖学参数,术中置入合适长度的拉力螺钉是可行的,可作为研发进钉瞄准器的应用解剖学依据.     

髋臼后柱骨折经皮逆行拉力螺钉固定的三维重建模型研究

目的 为髋臼后柱骨折经皮逆行拉力螺钉固定提供应用解剖学基础. 方法 收集60个正常成人骨盆的螺旋CT扫描数据,重建骨盆三维模型.模拟逆行拉力螺钉固定,在髋臼后柱置入虚拟三维圆柱体.计算其最大直径、长度、置入角度以及置入点(A)到坐骨结节远端(B)的距离.同时在相同的三维重建骨盆模型上,垂直髋臼内侧面对后柱进行重切,每间隔1 cm取一个截骨面,测量每个截骨面的内外径和上下径. 结果 男性半骨盆58个,女性半骨盆62个.虚拟三维圆柱体的平均最大直径为(13.16±1.45)mm,虚拟三维圆柱体与水平面、冠状面和矢状面的夹角分别为72.02°±6.05°、14.71°±6.98°和8.61°±3.96°,置入点位于坐骨结节内外侧缘的中线上,AB间距离为(15.18±1.97)mm.平均最小内外径和上下径分别为20.11 mm、19.19 mm,明显大于虚拟三维圆柱体的平均最大直径.虚拟三维圆柱体的直径、长度、与矢状面的夹角在男女之间的差异有统计学意义(P＜0.001). 结论 髋臼后柱可容纳7.3 mm的拉力螺钉,但男女的进针角度不同.螺钉的直径不能仅仅靠截骨面的直径确定.     

经皮逆行髋臼前柱螺钉内固定的计算机辅助应用解剖学研究

[目的]测量经皮逆行髋臼前柱螺钉内固定的应用解剖参数。[方法]收集本院2015年6月~2016年1月完整骨盆CT扫描数据男女各15例(男女各30侧半骨盆),应用Mimics计算机辅助外科软件,重建骨盆三维模型。模拟手术逆行置入髋臼前柱虚拟螺钉,调整好螺钉位置后测量螺钉长度、进钉点、进钉方向;通过软件的重切割功能,制作35层髋臼前柱系列截面,测量截面中螺钉所通过位置(即钉道)的直径。[结果]髋臼前柱可置入螺钉的最大工作长度男女分别为(119.79±8.71)mm、(104.10±5.84)mm;进钉点(P)到耻骨上支上缘(A)、耻骨联合(B)的垂直距离男性分别为(19.69±2.79)mm、(18.80±3.35)mm,女性分别为(18.27±2.13)mm、(22.92±3.34)mm;螺钉与冠状面、矢状面、横切面的夹角男性依次为(16.18±5.37)°、(41.76±4.78)°、(43.30±5.55)°,女性依次为(17.16±5.53)°、(43.12±3.90)°、(41.36±4.59)°;螺钉长度和PB男女之间的差异具有统计学意义(P<0.05),进钉方向和PA男女之间的差异无统计学意义(P>0.05)。前柱钉道最狭窄处位于第5层,该层截面中钉道直径男女分别为(11.43±1.24)mm、(8.75±0.95)mm,男女之间差异具有统计学意义(P<0.05)。[结论]作者建议国人男性使用直径为6.5 mm的螺钉,女性使用直径为5.5 mm的螺钉;进钉点男女稍有不同,在螺钉经过耻骨上支的中部和髂窝平面处两个狭窄地方时,应加强监视。     

髋臼前柱螺钉固定解剖学研究及导向器的设计

目的为经髋臼前柱螺钉固定提供解剖学依据。方法对22只成人尸体骨盆标本,共44侧髋臼进行解剖学研究,观测髋臼前柱横断面形状,测量髋臼前柱螺钉固定在髂骨翼外侧面的进针点、进针方向、钉道直径、进针点至闭孔沟的距离。结果髋臼前柱横断面呈近似直角三角形,钉道直径10.5±0.8mm;螺钉进针点位于髂骨翼后外侧面坐骨大切迹和髂前上棘连线上方9.2±2.4mm,距坐骨大切迹38.5±3.8mm;螺钉进针方向于水平面与中心线夹角为40.7±3.8°,矢状面向尾端成角54.2±5.5°。钉道长度84.1±6.2mm。并设计出髋臼前柱螺钉固定导向器。结论髋臼前柱可接受1枚直径6.5mm、长70mm的螺钉,螺钉进针点位于髂骨翼后外侧面坐骨大切迹和髂前上棘连线上方10mm,距坐骨大切迹40mm。螺钉进针方向于水平面与中心线夹角40°,矢状面向尾端成角55°。髋臼前柱螺钉固定导向器将提高前柱螺钉固定的安全性。     

髋臼在前柱投影的解剖学研究

目的探讨髋臼前柱的解剖学结构和螺钉放置的安全角度范围.方法取20具骨盆标本,在X线透视下确定髋臼上缘距髂前下棘顶点和髋臼下缘距髂外血管鞘外缘与骨盆缘交点的距离,CT垂直扫描前柱,测量距髋臼上缘0.5～4.0 cm(每0.5 cm测1次)的CT断面上前柱宽、髋臼宽.根据髋臼在前柱表面的投影,将前柱分为髋臼区、相对危险区和危险区,并测量距骨盆缘1 cm处φ2.5 cm螺钉进钉的安全角度.结果髋臼上缘在髂前下棘顶点上(1.1±0.1)cm,髋臼下缘在髂外血管鞘外缘与骨盆缘交点下(1.7±0.2)cm,距髋臼上缘0.5、1.0、1.5、2.0、2.5、3.0、3.5、4.0 cm的CT断面上,前柱平均宽分别为(55.7±4.8)、(54.4±2.0)、(50.5±3.7)、(41.3±3.0)、(39.1±4.6)、(35.2±5.7)、(31.7±5.6)、(30.8±3.4)mm;髋臼宽分别为(28.2±6.2)、(34.7±5.5)、(36.8±5.2)、(34.8±2.7)、(37.0±4.2)、(33.2±5.1)、(29.6±5.7)、(28.0±3.9)mm;距髋臼上缘0.5 cm断面进钉安全角度应＜87°±8°;距髋臼上缘1.0cm断面进钉的安全角度应＜76°±7°;距髋臼上缘1.5 cm断面进钉的安全角度应＜69°±7°;距髋臼上缘2.0 cm断面进钉的安全角度应＜63°±7°.结论髋臼中心部不能放置螺钉,中心部以上可以放置螺钉,进钉角度应＜63°±7°.     

髋臼螺钉固定安全性的解剖学研究

目的:探讨髋臼在其前、后柱上的投影和螺钉放置的安全范围。方法:取10具骨盆标本:在X线片透视下,(1)前柱测量:测量髋臼上缘投影与髂前下棘间的垂直距离和髋臼投影上缘与髂外血管鞘交点的垂直距离。(2)后柱测量:测量髋臼在其后柱投影上缘与坐骨大切迹顶点的垂直距离,下缘投影与坐骨棘的垂直距离。结果:(1)前柱:髋臼投影上缘在髂前下棘以远(1.97±0.10)cm,投影下缘在髂外血管鞘与前柱交点以远(1.48±0.06)cm。2、后柱:髋臼投影上缘在坐骨大切迹顶点以远(1.49±0.07)cm,投影下缘在坐骨棘以远(1.50±0.08)cm。结论:前柱利用髂前下棘和髂外血管鞘与前柱交点为标志,后柱利用坐骨大切迹顶点、坐骨棘和坐骨大孔缘为标志,能限定出髋臼在其前、后柱的投影,即螺钉固定危险区。     

髋臼后柱逆行经皮拉力螺钉固定的应用解剖

目的为临床应用髋臼后柱逆行经皮拉力螺钉内固定提供解剖学基础。方法取6具成人骨盆标本,行后柱逆行拉力螺钉固定。分别测量螺钉与水平面的夹角、与矢状面的夹角、钉长,以及使用三维CT重建图像测得拉力螺钉的最大直径等。结果对于髋臼后柱骨折,拉力螺钉与水平面的夹角为29.7°±2.3°、与矢状面的夹角为8.0°±2.5°,最窄处直径为(9.0±1.0)mm,平均钉长为(11.7±0.5)cm。结论髋臼后柱骨折逆行经皮拉力螺钉固定是安全、可行的。     

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.