安氏Ⅱ类错[牙合]畸形对青春期面部骨轮廓发育的影响

目的：研究安氏Ⅱ类错[牙合]畸形对青春期面部骨轮廓发育的影响。方法：收集安氏Ⅱ类错[牙合]畸形的成人患者和青少年患者共362例。摄取头颅定位侧位片及头颅定位正位片。对面高、面宽等19项测量项目做比较分析及t检验。结果：①安氏Ⅱ类青少年患者与正常[牙合]青少年相比，下颌基骨长度、下颌长度较小，但无统计学差异。②安氏Ⅱ类成年患者与正常牙A成年人相比，下颌基骨长度、下颌长度有显著性差异。③安氏Ⅱ类患者下颌骨在青春发育期有向前、向上旋转的趋势。结论：安氏Ⅱ类错[牙合]畸形患者经过青春期发育，使面部畸形程度更加严重。本研究得出安氏Ⅱ类错[牙合]畸形对青春期面部骨轮廓发育的影响，对正颌外科和正畸治疗具有参考意义。     

Frankel Ⅲ矫治器对混合牙列期安氏Ⅲ类错的疗效

目的:研究经Frankel Ⅲ型矫治器矫治1年后的青少年面部硬组织变化。方法:选取安氏Ⅲ类错患者25例,在生长快速期使用Frankel Ⅲ型矫治器矫治1年,于治疗前后拍摄X线头颅侧位片,另收集128例同龄安氏Ⅲ类错患者的X线头颅侧位片资料作为对照组,进行头影测量分析。结果:经过Frankel Ⅲ型矫治器治疗1年,患者下颌骨长度发育受到抑制,减小后面高的增长,ANB角增加,SNB角减小,下颌相对于颅底的位置向后移动;下颌平面及平面发生顺时针方向的旋转。结论:经Frankel Ⅲ型矫治器矫治1年,下颌生长会受到抑制,向后下方旋转生长。     

改良颊侧多曲簧矫治器纠正早期安氏Ⅲ类错伴下颌偏斜

目的:通过头颅定位后前位片测量,探讨改良颊侧多曲簧活动矫治器纠正早期安氏Ⅲ类错且伴下颌功能性偏斜,改善早期功能性下颌偏斜。方法:混合牙列早期安氏Ⅲ类错且伴有下颌功能性偏斜患者20例,采用改良颊侧多曲簧活动矫治器的方法,矫治前后头颅定位后前位片P-A测量分析,用统计软件处理数据。结果:改良颊侧多曲簧活动矫治器矫正早期安氏Ⅲ类错且伴有下颌功能性偏斜后,下颌骨两侧结构不对称性有明显改善,下颌骨两侧综合长度差亦减小(P<0.01),两侧下颌体长度差明显减小(P<0.01)。结论:由于早期安氏Ⅲ类错且伴有单侧后牙反,导致的功能性下颌偏斜,采用改良颊侧多曲簧活动矫治器,可以使下颌骨的不对称得到一定的改善,是早期纠正下颌功能性偏斜的有效手段。     

双垫功能矫治器及直丝弓固定矫治器联合治疗安氏Ⅱ类1分类错畸形的效果研究

目的:双垫矫治器(Twin block矫治器)及直丝弓固定正畸联合矫治安氏Ⅱ类1分类错畸形的效果。方法:选择11例(男5例,女6例)10～13岁以下颌后缩为主的安氏Ⅱ类错畸形患者应用Twinblock及直丝弓固定正畸联合矫治。每位患者治疗前拍摄头颅侧位片、曲面断层X线片。对Twin block及直丝弓固定正畸联合矫治前后头颅侧位X线片进行测量。结果:SNA、ANB、OJ、UI\SN减小,SNB、LI\MP、Sn-A’-UL、LL-B’-Pos增大,下颌升支、下颌体长及下颌综合长度均有增长,差异均有显著性。结论:Twinblock矫治器治疗恒牙早期安氏Ⅱ类1分类错畸形,能明显减小前牙覆、覆盖,增加上颌弓宽度,促进下颌生长,有效改善患者下颌后缩的面型。联合固定正畸可达到良好的治疗效果。     

青少年骨性Ⅱ类错前后平面的测量分析

目的:探讨分析青少年骨性Ⅱ类错不同垂直骨面型患者前、后平面的特点。方法:选取青少年骨性Ⅱ类错畸形患者共158例,按垂直生长型将其分为高、低及均角三组,采用Winceph8.0软件对每例患者的头颅侧位定位片进行前、后平面及其相关颌骨指标的定点测量,结果进行统计学分析。结果:前、后平面倾斜度,下颌支角(Go-A)和下颌支倾斜角(RAM-I)均为高角组均角组低角组(P0.05)。结论:青少年骨性Ⅱ类错不同垂直骨面型前后平面存在差异,高角者前后平面更为陡峭,颌骨也表现出相应的形态特征。     

骨性安氏Ⅲ类错患者不同垂直骨面型下颌联合高度差异的临床研究

目的:比较不同的垂直骨面型的骨性安氏Ⅲ类错患者下颌联合高度的差异。方法:在未做过正畸治疗的115例患者的头颅侧位片上测量下中切牙-下颌平面角(incisor mandibular plane angle,IMPA)以及下颌联合高度(symphysis height,LH),比较不同垂直骨面型的骨性安氏Ⅲ患者的下颌牙槽代偿和下颌联合高度的差异。结果:下颌联合高度和下中切牙-下颌平面角在不同垂直骨面型的安氏Ⅲ类患者中存在明显差异。在骨性安氏Ⅲ错中,下颌联合高度(LH)与下颌平面角呈正相关,下中切牙-下颌平面角(IMPA)与下颌平面角呈负相关。结论:骨性安氏Ⅲ类错患者长面型的趋势导致下颌联合变长,下前牙代偿性舌倾随着长面型的趋势加重。     

自锁托槽结合平面导板在安氏Ⅱ类2分类错畸形中的应用研究

目的:通过临床验证自锁矫治体系的作用效果,为临床高效、合理地选择矫治体系提供参考。方法:临床选取不需拔牙的安氏Ⅱ类2分类错畸形患者20例,随机分为两组,每组10例。实验组接受自锁矫治系统,对照组接受直丝弓矫治系统,均戴入上颌平面导板打开咬合。矫治前后分别拍摄X线头颅定位片,制取记存石膏模型。选取X线硬组织和石膏模型指标分析测量,配对t检验,比较两种方法矫治前后牙颌组织的变化有无统计学差异。结果:两种方法矫治前后上、下牙弓宽度和牙弓长度均增加,但两组间差异无统计学意义(P>0.05);两种方法基骨弓宽度均略有增加,两组间的差异有显著性(P<0.05);两种方法上颌基骨弓长度治疗前后未见明显增加,下颌基骨弓长度治疗前后均有明显增加,上下前牙唇倾度均有明显改善,但两组间,无明显差异。治疗完成时间实验组比对照组缩短,两组间有显著性差异。结论:自锁系统能够扩展牙弓和基骨弓宽度,唇倾前牙,有利于三维方向解除闭锁,在扩展基骨弓宽度上,略优于直丝弓,配合平面导板,可防止托槽脱落、快速打开咬合,缩短治疗时间,特别适合用于安氏II类2分类错畸形的矫治。     

用Alabama分析法比较安氏Ⅰ类错中国人与美国白人颅颌面结构差异

目的:研究中国安氏Ⅰ类错成人与美国安氏Ⅰ类错白人牙颌颅面形态结构的差异。方法:从西安市11所大学2098名新生中选取符合标准的101名(男53名、女48名)安氏Ⅰ类错样本。拍摄头颅定位X线片,用第四军医大学口腔医学院头影测量软件测量,用Alabama分析法与美国安氏Ⅰ类错白人颅颌面测量结果进行比较分析。结果:中国西安地区安氏Ⅰ类错成人上下颌突度大,面型较突;平面倾斜度、上下中切牙倾斜度及下中切牙至NB线距均较大;Y轴相对SN平面夹角增大,生长方向为后下。结论:与美国安氏Ⅰ类错白人比较,中国西安地区安氏Ⅰ类错成人颅面结构呈现颌骨突度大、下切牙唇倾及下颌趋向后下等特征。     

安氏Ⅲ类错的下颌形态研究

目的:采用几何形态测量法来探讨骨性Ⅲ类错下颌形态的特征。方法:随机选取恒牙初期骨性Ⅲ类与Ⅰ类错患者头颅侧位片各30张,描记下颌的16个标志点,数字化后采用Procrustes重叠法、薄板曲线法、欧式距离矩阵法和常规头影测量法,以骨性Ⅰ类错患者作为对照组,对骨性III类错与Ⅰ类错进行两组间t检验从而对其下颌形态进行比较。结果:Ⅲ类错与Ⅰ类错相比,下颌形态有差异(P<0.05),Ⅲ类错组髁状突长度、升支高度、下颌体长度增加,颞颌关节、颏部都靠前,下切牙舌倾。结论:III类错的下颌形态有其自身特点,并影响Ⅲ类错的形成。     

Pancherz分析法评价不拔牙方法治疗发育高峰期安氏Ⅱ类1分类错畸形的临床疗效

目的:评价不拔牙方法治疗生长发育高峰期安氏Ⅱ类1分类错畸形的临床疗效。方法:对22例10~14岁安氏Ⅱ类1分类错患者进行快速扩弓,运用直丝弓矫治技术完成不拔牙矫治。采取Pancherz二类错矫正分析方法结合传统测量项目分析治疗前后头颅侧位片,用SPSS 17.0统计软件对18项测量数据进行统计分析。结果:患者治疗后,下颌骨发生明显前移,SNB角平均增加了2.30°,ANB角平均减小2.14°。下颌骨长度平均增加了2.67m,覆盖减小5.95mm,上中切牙明显内收。磨牙关系均调整为中性关系,下颌平面未发生明显旋转。结论:上下联合扩弓结合直丝弓矫治技术,能保留全口牙列,改善下颌后缩面型,是治疗轻中度拥挤的安氏Ⅱ类1分类错畸形的有效方法之一。     

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.