直肠癌保肛手术中侧方清扫保留盆腔自主神经124例的疗效评价

目的探讨直肠癌保肛手术中侧方淋巴结清扫和保留盆腔自主神经的临床疗效。方法回顾性分析124例直肠癌保肛手术患者经侧方淋巴结清扫和保留盆腔自主神经后的排便、排尿、性功能及术后生存情况。结果112例患者（90．3％）于术后3d内拔除尿管,平均导尿时间为（58．3±2．1）h。最大尿意尿量为（401．2±23．1）ml,残余尿量为（28．2±2．2）ml。19例术后发生大便失禁,11例经排便训练后基本恢复,2例自行缓解。术后问卷调查98例患者的性功能显示：62．3％的患者可以正常勃起,57．1％的患者有正常的性功能。保留自主神经患者的5年生存率为61．2％。结论直肠癌保肛手术中侧方淋巴结清扫和保留盆腔自主神经能良好保留肛门功能并减少术后排尿及性功能障碍的发生,不影响生存率。     

超声刀联合双吻合器在开放直肠癌低位前切除术中的应用

目的探讨超声刀联合双吻合器在开放直肠癌低位前切除术中的临床应用价值。方法40例拟行直肠癌低位前切除的患者随机分为应用超声刀联合双吻合器20例作为研究组,应用高频电刀联合单吻合器20例作为对照组。比较两组的保肛成功率,同时观察保肛成功病例两组间手术时间、术中出血量、术后第1个24h引流量、术后并发症、肠功能恢复时间及住院时间的差异。结果研究组保肛成功19例（95％）,对照组保肛成功14例（70％）,两组相比P=0．037;33例保肛成功患者中,研究组手术时间（102．5±14．6m）较对照组（114．7±17．5m）明显缩短（P=0．032）;研究组手术出血量（62．5±19．3m1）较对照组（91．3±26．5m1）显著减少（P=0．001）;术后第1个24h引流量研究组和对照组分别为33．6±15．0ml、65．7±25．9ml（P〈0．001）;术后首次排气时间分别为2．4±0．6天、2．9±0．4天（P=0．004）;术后平均住院天数研究组较对照组也显著缩短（P=0．014）;两组术后并发症差异无显著性（P=0．674）。结论开放直肠癌低位前切除术中应用超声刀联合双吻合器是直肠癌手术向微创手术理念和快速康复外科理念发展的尝试．在开放盲肠痛手术领域具有广泛的府用前景。     

腹腔镜下肾切除术转手助腹腔镜与转开放手术的疗效比较

目的对困难腹腔镜下肾切除手术进行探索，并观察转手助腹腔镜与转开放手术的术中与术后临床指标，为临床应用提供参考。方法1999年12月至2006年11月行各类腹腔镜下肾切除手术273例，23例因出血、粘连、肿瘤侵犯周围脏器等原因改变手术方式。其中转手助腹腔镜手术组12例，男8例，女4例，年龄19-73岁，平均52岁，左侧7例，右侧5例；转开放手术组11例，男6例，女5例，年龄32-68岁，平均48岁，左侧5例，右侧6例。观察2组改变手术方式后的手术时间、出血量、切口长度、术后起床活动时间、肛门排气时间、住院时间等指标。结果转开放组1例死亡，其余病例均顺利完成。转手助腹腔镜组改变手术方式后手术时间为（40．1±12．5）min，术中出血量（377±311）ml，切口长度（6．2±2．7）cm，肛门排气时间（2．2±0．6）d，下床活动时间（2．2±1．1）d，术后住院时间（5．4±1．6）d；转开放手术组改变手术方式后手术时间（80．2±37．6）min，术中出血量（854士306）ml，切口长度（19．8士2．5）cm，肛门排气时间（2．5±0．5）d，下床活动时间（4．2±0．8）d，术后住院时间（10．2±2．9）d。与转开放组相比，转手助腹腔镜组在改变手术方式后手术时间、出血量、切口长度、下床活动时间、术后住院时间方面均有明显优势（P〈0.01）。结论腹腔镜下肾切除手术遇到困难时，转手助腹腔镜手术可作为一项安全合理的选择，较转开放手术出血少、创伤小，恢复快。     

腹腔镜全直肠系膜切除治疗低位直肠癌(附198例临床资料报告)

目的探讨腹腔镜全直肠系膜切除治疗低位直肠癌的可行性和安全性。方法回顾分析198例腹腔镜全直肠系膜切除治疗低位直肠癌病例资料。结果全组无手术死亡,无中转开腹。平均手术时间（211.5±69.2）min,中位出血量80（50～200）mL,平均切除淋巴结数为（11.5±6.4）枚,平均肛门排气时间（2.8±1.4）d,平均可下地行走时间（1.6±0.9）d,平均术后住院时间（11.8±6.4）d。术后并发症发生率为20.71%,最常见为肠梗阻（占并发症的24.4%）。中位随访时间为26.1（13.6～45.2）个月,随访率86.9%。33例出现术后复发转移,其中吻合口复发2例,盆腔局部复发3例,腹腔广泛转移4例,远处转移24例。死亡共37例,其中死于肿瘤相关因素28例,死于非肿瘤相关因素9例。5例带瘤生存。结论腹腔镜全直肠系膜切除治疗低位直肠癌不仅具有疼痛轻、恢复快等优点,在技术上也是安全可行的,而最终的结果仍有待于大量的、长期的前瞻性随机对照研究。     

腹腔镜手术治疗老年良性妇科疾病的价值

目的探讨腹腔镜手术在老年妇科良性疾病中的应用价值及安全性。方法比较2001年1月～2006年12月27例腹腔镜手术（腹腔镜组）与25例开腹手术（开腹组）的临床资料。结果腹腔镜组手术时间（20．0±7．9）min明显短于开腹组（44．0±7．2）min（t=-11．419，P：0．000）；腹腔镜组术中出血量（21．9±20．0）m1明显少于开腹组（62．6ml±29．4）（t=-5．875，P：0．000）；腹腔镜组术后病率3例明显少于开腹组12例（，：8．606，P：0．001）；腹腔镜组术后排气时间（13．9±2．9）h明显短于开腹组（23．4±4．3）h（t=-9．404，P=0．000）；腹腔镜组住院时间（7．6±0．9）d明显少于开腹组（10．2±1．2）d（t=-8．882，P=0．000）。结论重视老年患者术前合并症的治疗，术中术后加强监护，腹腔镜是老年妇科疾病手术治疗理想的术式。     

腹腔镜与开放性离断式肾盂成形术的疗效比较

目的比较腹腔镜与开放性离断式肾盂成形术治疗肾盂输尿管连接部梗阻（UPJO）的手术疗效。方法采用经腹腔途径腹腔镜下离断式肾盂成形术38例（A组）。男21例，女17例。年龄8～67岁，平均34岁。病变位于左侧23例，右侧15例。重度肾积水21例，中度17例。经腹膜后开放性离断式肾盂成形术40例（B组）。男18例，女22例。年龄9～63岁，平均32岁。左侧26例，右侧14例。重度肾积水22例，中度18例。对2组的手术时间、术中出血量、术后恢复、临床疗效及并发症进行比较研究。结果A组手术均获成功，无中转开放手术者，手术时间（137．1±30．5）min，术中出血量（143．8±45．2）ml，术后止痛药应用时间（O．8±0．2）d，术后住院时间（7．1±1．2）d，恢复工作时间（24．3±5．6）d。术后发生漏尿1例，经B超引导下肾盂穿刺造瘘3d后痊愈。术后随访6～36个月，吻合口无狭窄，肾积水减轻，中度肾积水12例、轻度积水15例、肾积水消失11例。B组手术时间（135．2±34．6）min，术中出血量（245．3±80．9）ml，术后止痛药应用时间（1．5±0．5）d，术后住院时间（10．3±2．6）d，恢复工作时间为（43．2±11．4）d。发生漏尿2例，分别引流5d和8d治愈；切口感染2例，经换药加抗生素治疗2周后好转；1例腹膜后血肿形成者经再次手术清除腹膜后血肿、止血后于术后第21天出院。术后随访6～36个月，1例吻合口狭窄伴重度积水，其余肾积水减轻（中度肾积水9例、轻度积水16例、肾积水消失14例）。2组手术时间比较差异无统计学意义（P＞0．05），术中出血量、术后止痛药应用时间、术后住院时间、恢复工作时间比较差异均有统计学意义（P＜0．01）。结论腹腔镜与开放性离断式肾盂成形术相比，手术时间相当，前者出血少、创伤小、痛苦轻、并发症少、术后恢复快，术后长期疗效相当。     

3种手术方法治疗肾上腺肿瘤的比较

目的比较小切口腹腔镜与后腹腔镜、开放性手术治疗肾上腺肿瘤的临床价值。方法2003年1月-2006年7月我院对95例肾上腺肿瘤分别采用小切口腹腔镜手术（n=12）,后腹腔镜手术（n=23）,开放性手术（n=60）,比较3组术中、术后情况。结果后腹腔镜手术组手术时间（142.6±41.3）min明显长于小切口腹腔镜组（72.9±13.7）min和开放手术组（96.7±40.9）min（q=7.140,P〈0.05;q=6.827,P〈0.05）;开放手术组术中出血量（232.0±89.2）ml明显多于小切口腹腔镜组（125.0±58.4）ml和后腹腔镜手术组（119.6±63.5）ml（q=5.947,P〈0.05;q=8.055,P〈0.05）;开放手术组术后肠功能恢复时间（4.1±0.8）d明显长于小切口腹腔镜组（2.7±1.2）d和后腹腔镜手术组（2.7±0.9）d（q=7.106,P〈0.05;q=9.163,P〈0.05）;开放手术组术后住院时间（12.6±3.2）d明显长于小切口腹腔镜组（6.7±2.7）d和后腹腔镜手术组（6.3±1.4）d（q=9.383,P〈0.05;q=12.919,P〈0.05）。3组术后复发无统计学意义（χ^2=0.621,P=0.733）。结论与开放手术相比,小切口腹腔镜和后腹腔镜手术具有创伤小、出血少、恢复快等优点;小切口腹腔镜为巨大肾上腺肿瘤切除提供了微创手术的新方式。     

超低位直肠癌腹腔镜辅助下经肛门拖出吻合术（附21例报告）

目的探讨腹腔镜下经肛门拖出式保肛手术在超低位直肠癌治疗中的应用。方法对21例行经肛门拖出式腹腔镜超低位直肠癌保肛手术病人的临床资料进行回顾性分析。结果本组平均手术时间为（200±40）min，平均出血量为（40±10）ml。术中发现吻合口瘘1例；术后发生吻合口瘘2例，吻合口狭窄2例，术后出血4例，盆腔感染4例。术后随访21例，随访时间为5～50月。行超低位吻合的13例6个月内排便正常，行结肠肛管吻合的8例9个月内排便正常。本组无局部复发病例，发生肝转移2例。结论腹腔镜下经肛门拖出式超低位直肠癌保肛手术确实可行，对于中、早期及组织学分型好的超低位直肠癌病人是较好的选择。     

腹腔镜与开腹全子宫切除术的比较

目的 探讨腹腔镜全子宫切除（total laparoscopic hysterrectomy,TLH）的临床价值. 方法回顾分析我院2005年11月～2006年10月38例TLH与40例开腹全子宫切除术的临床资料,比较2种手术方式手术时间、术中出血量、术后病率、肠功能恢复、住院日情况. 结果 腹腔镜组手术时间（85.8±13.8）min明显短于开腹组（99.9±9.3 ）min（t=-5.293,P=0.000）;腹腔镜组出血量（105.8±32.4）ml明显少于开腹组（166.0±67.4）ml （t=-4.930, P=0.000）;腹腔镜组术后病率3例明显少于开腹组15例（χ^2=9.270, P=0.002）;腹腔镜组术后排气时间（26.2±4.2）h明显短于开腹组（40.5±4.9）h （t=-13.601, P=0.000）;腹腔镜组术后住院时间（6.8±0.9）d明显短于开腹组（10.6±0.8）d （t=-19.612, P=0.000）.术后6个月随访开腹组2例切口愈合不良,2例阴道残端肉芽增生,腹腔镜组1例阴道残端肉芽增生,余无并发症. 结论腹腔镜全子宫切除较开腹全子宫切除的优势明显,如果腹腔镜下操作技巧熟练,腹腔镜全子宫切除是一种理想的术式.     

完全经肛腔镜下全直肠系膜切除术五例

目的：初步探讨完全经肛腔镜下进行直肠癌根治术的可行性。方法回顾性分析2014年7月在中山大学附属第六医院行完全经肛门腔镜下直肠癌根治术5例患者的临床资料。结果5例患者中4例女性，1例男性，年龄（46．8±8．0）岁，均顺利完成手术，无一例中转腹腔镜辅助或开腹手术。手术时间（115．0±29．2） min，第5例仅45 min即完成手术；术中出血（24．0±15．2） ml；术后排气时间（1．6±0．5） d；术后住院时间（6．0±0．7） d；术后标本淋巴结获取（15．6±3．5）枚；无术后感染及吻合口并发症的发生。结论完全经肛腔镜下手术可以达到直肠癌根治的目的，并且具有手术时间短、术后恢复快和住院时间短的优点，是中低位直肠癌手术的新选择。     

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.