栓钉式游离牵引钩与传统游离牵引钩的机械力学对比

背景:游离牵引钩是直丝弓矫治器滑动法移动牙齿的一种常用装置。传统的游离牵引钩的缺点是固位力不足,加力后牵引钩容易在弓丝上滑动,从而不能达到整体移动牙齿的目的。目的:研发一种新型栓钉式游离牵引钩,检测其静态抗移位性能,并与传统牵引钩对比。方法:设计并生产一种由开口的箱状体、牵引钩和栓钉组成的新型游离牵引钩。30个新型牵引钩和30个AO游离牵引钩分别安置于0.019×0.025英寸不锈钢方丝上,分别放到多用途加载机上进行加载,测量每个牵引钩在弓丝上移位所需的力值。比较两种牵引钩的抗移位性能。结果与结论:移动新型牵引钩所需的力值(22.37±9.06)N明显大于移动AO游离牵引钩所需的力值(4.96±0.70)N(P<0.01)。与传统的游离牵引钩相比较,栓钉式牵引钩具有结构更合理,固位原理更先进,以及优异的抗移位性能。     

氨溴索对机械通气患者呼吸力学及氧化应激的影响

目的 研究氨溴索针剂对慢性阻塞性肺疾病(COPD)并呼吸衰竭患者机械通气过程中呼吸力学及氧化应激的影响。方法 COPD并呼吸衰竭的机械通气患者，在机械通气过程中分别采用氨溴索针剂和必漱平针剂治疗，监测气道峰压(PIP)、平台压(Pplat)、平均气道压(Pm)、内源性呼气末正压(PEEPi)、静态顺应性(Cs)、动态顺应性(Cd)和吸气阻力(Ri)变化，并检测了血清丙二醛(MDA)、谷胱甘肽(GSH)含量，超氧化物歧化酶活性(SOD)及总抗氧化能力(TAO)水平。结果 氨溴索治疗显著降低患者Ri、PIP、Pplat、Pm、PEEPi水平，显著增高Cs、Cd水平，并使血清MDA含量显著降低，SOD、GSH及TAO水平显著提高。结论 氨溴索治疗对COPD并呼吸衰竭的机械通气患者呼吸力学状态具有明显改善作用，并能减轻患者氧化应激水平，对呼吸机相关性肺损伤具有保护作用。     

新型游离微型穿支皮瓣与传统游离皮瓣修复手指皮肤缺损比较

目的:观察并对比新型游离微型穿支皮瓣与传统游离皮瓣修复手指皮肤缺损的效果,及对患者美容满意度的影响。方法:选取我院2014年1月～2018年1月收治的手指皮肤缺损患者94例,采用随机数字表法分为对照组与观察组,各47例。对照组采用传统游离皮瓣修复术治疗,观察组采用新型游离微型穿支皮瓣修复术治疗。对比两组并发症发生情况,修复前后手功能、疼痛评分,修复效果及患者对修复的满意度。结果:观察组并发症总发生率明显低于对照组(P0.05);修复前两组手功能、疼痛评分对比,差异无统计学意义(P0.05);修复后观察组手功能评分高于对照组,疼痛评分低于对照组(P0.05);观察组修复总有效率高于对照组,对修复满意度高于对照组,差异有统计学意义(P0.05)。结论:采用新型游离微型穿支皮瓣修复术修复手指皮肤缺损并发症发生率较低,可显著改善患者手指功能评分与疼痛评分,提高修复效果及患者对美容的满意度。     

新生儿呼吸衰竭机械通气撤机时的肺力学研究

目的探讨新生儿机械通气撤机时肺力学指标的范围及临床意义。方法通过Bicore-CP 100呼吸功能监测仪测定32例机械通气撤机时的新生儿在CPAP模式、脱机拔管前及拔管后20 min等条件下的肺力学指标范围,根据拔管48 h内是否重新插管并分为撤机成功组与失败组。结果成功组的呼吸力学范围为:气道阻力(Rawmean)(93.7±14.3)cmH2O/(L.s)、呼吸系统顺应性(Crs)(0.65±0.09)ml/(cmH2O.kg)、患者呼吸功(WOBp)(1 589±133.2)g.cm/(min.kg);失败组为:Rawmean(98.6±15.5)cmH2O/(L.s)、Crs(0.57±0.08)ml/(cmH2O.kg)、WOBp(1 782±148.6)g.cm/(min.kg)。Crs与WOBp两组差异有显著性。Crs(0.65±0.09)ml/(cmH2O.kg),脱机成功率95.4%。撤机后拔管前两组平均WOB为(1 768±186.4)g.cm/(min.kg),Crs为(0.624±0.11)ml/(cmH2O.kg),脱机成功率为81.25%。结论肺力学的检测对新生儿呼吸机的撤离具有指导作用,特别是呼吸系统顺应性和呼吸功的检测更具有实质意义。     

早产儿呼吸衰竭同步机械通气治疗的呼吸力学评价

目的　探讨同步间歇性指令通气 (SIMV )在早产儿机械通气中的临床意义。方法　 4 2例机械通气的早产儿随机分成两组 ,SIMV组 2 4例 ,间歇性指令通气 (IMV)组 18例 ,观察两组呼吸机参数、呼吸力学参数变化 ,以及并发症的发生率及镇静剂的使用次数。结果　上机 2 h后吸气峰压 (PIP)、呼气潮气量 (VTexp)、呼吸系统顺应性 (Crs)、气道阻力 (Raw) ,12 h后吸氧浓度 (Fi O2 ) SIMV组均明显优于 IMV组 ,2 4 h氧合指数(OI) SIMV组明显少于 IMV组 ;镇静剂的使用次数 SIMV组少于 IMV组 ,两组差异均有显著性 (P<0 .0 5或P<0 .0 1) ;并发症的发生率两组差异无显著性 (P均 >0 .0 5 )。结论　早产儿呼吸衰竭机械通气时使用 SIMV模式较 IMV能更快降低 Fi O2 、PIP、OI,较快改善肺功能 ,减少镇静剂和肌松剂的使用率。     

早产儿机械通气不同脱机模式的呼吸力学评价

目的 :从呼吸力学的角度评价低出生体重儿机械通气不同脱机模式的优劣及临床意义。方法 :通过 BicoreCP- 10 0呼吸监测仪测定 2 1例早产儿在 IMV、SIMV、CPAP模式、脱机拔管前及拔管后 2 0 min等条件下的呼吸力学的变化。结果 :CPAP 3cm H2 O时 WOBp明显高于 SIMV、IMV组 ,有显著性差异 ;脱机后 WOBp明显降低 ,与 3组比较 ,有显著性差异。 CPAP模式下 0、1、2、4 h WOBp明显改变 ,4 h与 0 h有显著性差异。结论 :不同脱机模式下 WOBp存在差异 ,早产儿呼吸机的撤离以低频率的 SIMV、IMV模式较为适宜 ,而 CPAP模式不适合早产儿呼吸机的撤离。     

正压机械通气与膈肌起搏联合通气对呼吸衰竭患者呼吸力学的影响

目的 观察正压机械通气与膈肌起搏联合通气对呼吸衰竭(呼衰)患者呼吸力学的影响.方法 采用自身前后对照研究方法,以20例中枢性呼衰患者先使用常规正压机械通气30 min作为对照组,后改用正压机械通气与膈肌起搏联合通气30 min作为试验组,观察两种通气方式下患者的呼吸力学变化.结果 与对照组比较,试验组平均气道压(Paw,cm H2O,1 cm H2O=0.098 kPa)、平台压(Pplat,cm H2O)明显降低(Paw:6.1±1.3比7.3±1.8;Pplat:10.4±2.5比12.1±2.6,均P＜0.05),峰食道压力(PPEAK ES,cm H2O)、峰食道压力与基准食道压力差(dPES,cm H2O)负值明显增加(PPEAK ES:-8.3±1.9比-3.2±1.4;dPES:-11.2±2.6比-8.2±2.2,均P＜0.05),吸气末屏气期间的跨肺压(Ptp plat,cm H2O)、呼吸系统静态顺应性(Cst,ml/cm H2O)明显增加(Ptp plat:23.6±3.8比15.6±3.1 Cst:52.7±8.2比48.3±7.2,均P＜0.05),气道阻力(Raw,cm H2O·L-1·s-1)、肺部阻力(RL,cm H2O·L-1·s-1)无明显改变(Raw:2.1±0.5比2.3±0.4; RL:2.9±0.6比3.1±0.5,均P＞0.05),患者呼吸功(WOBp,J/L)明显增加、机械呼吸功(WOBv,J/L)明显降低(WOBp:0.18±0.03比0;WOBv:0.31±0.07比0.53±0.11,均P＜0.05).结论 正压机械通气与膈肌起搏联合通气进行呼吸支持可明显降低呼衰患者气道压力,增加胸腔内压负值和跨肺压,提高肺顺应性,并能降低机械通气作功,但对气道阻力无明显影响.

Abstract：

Objective To observe the effects of combining positive pressure ventilation with diaphragm pacing on respiratory mechanics in patients with respiratory failure. Methods Twenty patients with central respiratory failure were studied with cohorts. The effects on respiratory mechanics were respectively observed in patients in control group, in whom ventilation by positive pressure only, and patients in experimental group in whom ventilation was instituted by combining positive pressure ventilation with diaphragm pacing. Results Compared with control group, mean airway pressure (Paw, cm H2O,1 cm H2O= 0. 098 kPa) and plateau pressure (Pplat, cm H2O) were significantly decreased in experimental group (Paw: 6. 1±1.3 vs. 7. 3±1.8; Pplat: 10. 4±2.5 vs. 12. 1±2. 6, both P＜0. 05), while the nagative value of peak esophageal pressure (PPEAK ES, cm H2O), the nagative value of the difference between peak and basic esophageal pressure (dPES, cm H2O), transpulmonary pressure at end of inspiration hold (Ptp plat,cm H2O), static compliance (Cst, ml/cm H2O) were significantly increased in experimental group (PPEAKES:-8.3±1.9 vs. -3.2±1.4; dPES: -11.2±2.6 vs. -8. 2±2. 2; Ptp plat: 23.6±3.8 vs. 15.6±3.1; Cst:52. 7±8. 2 vs. 48. 3 ±7. 2, all P ＜ 0. 05 ). No differences were found in airway resistance (Raw,cm H2O · L-1 · s-1) and lung resistance (RL, cm H2O · L-1 · s-1) between experimental group and control group (Raw: 2.1±0.5 vs. 2.3±0.4; RL: 2.9±0.6 vs. 3.1±0.5, both P＞0.05). Work of breath by patient (WOBp, J/L) was significantly increased and work of breath by ventilator (WOBv, J/L) was significantly decreased in experimental group compared with control group (WOBp: 0. 18± 0. 03 vs. 0;WOBv: 0.31±0.07 vs. 0.53±0.11, both P＜0.05). Conclusion Compared with positive pressure ventilation, positive pressure ventilation combined with diaphragm pacing can decrease the Paw, increase intrathoracic negative pressure, transpulmonary pressure, and Cst, and decrease WOBv, while there is no effect on Raw and RL.     

从细胞力学的角度探讨手法力学刺激所致细胞应力效应

推拿治疗对机体的作用在本质上是力学刺激,但一直缺少微观探讨,给临床、科研带来不便,严重制约推拿学的发展。其中手法在细胞层面的研究明显滞后。基于单细胞分析的细胞组学研究给这一难题的解决带来转机,同时机械力对细胞生物学行为的影响是目前细胞生物学领域研究的重要课题,将其引入推拿学领域具有重要意义,有助于从细胞力学层面研究手法治病的作用机制。     

镇静对机械通气患者呼吸力学及氧代谢的影响

目的探讨镇静对机械通气病人呼吸力学、肺内分流率、氧代谢的影响。方法60例机械通气患者随机分为对照组和镇静组,镇静组给予丙泊酚,维持患者镇静水平于RamsayⅢ～Ⅳ级;对照组给予同等剂量的生理盐水,用药前及2h后抽取肺动脉混合静脉血和动脉血行血液气体分析,同时记录心率、血压、呼吸频率、气道阻力。两组间比较采用t检验。结果用药后两组患者的氧合指数、血压、血乳酸、肺静态总顺应性和肺内分流率差异无统计学意义;心率、呼吸频率、氧摄取率和气道阻力镇静组低于对照组（P〈0．05）;混合静脉血氧分压镇静组高于对照组（P〈0．05）。结论镇静可以降低机械通气患者的氧摄取率和气道阻力;对氧合指数、肺静态总顺应性和肺内分流率无影响。     

长托宁雾化吸入对机械通气病人呼吸力学的影响

[目的]观察盐酸戊乙奎醚（长托宁）雾化吸入对气管插管覆机械通气病人的呼吸力学指标的影响。[方法]选择49例气管插管及机械通气病人，将病人随机分为两组，观察组雾化吸入长托宁，对照组雾化吸入盐酸氨溴索，记录雾化前及雾化后10min、30min、60min呼吸力学指标的变化。[结果]雾化后观察组气道峰压、呼吸阻力与对照组相比明显降低（P〈0．05），肺顺应性明显高于对照组（P〈0．05）。[结论]长托宁雾化吸入用于气管插管度机械通气病人，可有效降低病人的气道峰压、呼吸阻力。同时改善肺顺应性。     

Effect of hemodialysis on traditional and innovative cardiac markers

The diagnostic approach to acute coronary syndrome (ACS) is challenging in patients with impaired renal function since most serum biomarkers are commonly increased in this clinical setting. Cardiac troponin T (cTnT), creatine kinase isoenzyme MB (CK MB), myoglobin, and ischemia modified albumin (IMA), were assayed in 45 patients prehemodialysis (pre-HD) and posthemodialysis (post-HD), and results were adjusted for hemoconcentration. The pre-HD values of serum IMA and cTnT were above the respective diagnostic thresholds (IMA<85 K units/L; cTnT <0.03 ng/mL) in six (13%) and 27 (60%) patients undergoing chronic HD, respectively. A significant (105.0 vs. 79.0 K units/L, P<0.0001) and variable (+38%; 95% confidence interval [CI], 12-65%) increase of serum IMA was observed post-HD, whereas the other biomarkers significantly decreased (cTnT: 0.029 vs. 0.044 ng/mL, P=0.016; CK-MB: 2.33 vs. 2.50 microg/L, P<0.0001; myoglobin: 128.1 vs. 148.7 microg/L, P<0.0001). Biomarkers of myocardial injury, especially cTnT and IMA, might be used in HD patients, provided that an appropriate diagnostic interpretation is guarantee, according to individual baseine value, metabolism, and time of sampling. Moreover, IMA might be reliably applied to stratify the long-term risk of these patients, but not for diagnosing an ACS during or immediately post-HD.     

Torsional stability of intramedullary compression nails: tibial osteotomy model

BACKGROUND: Studies comparing intramedullary compression nailing to conventional dynamized intramedullary nailing contend that better clinical outcomes of intramedullary compression techniques result from greater rotational stability of fracture or osteotomy sites. However, there appears to be no experimental evidence that rotational stability is improved with intramedullary nail compression. This study evaluated the effect of intramedullary nail compression on cadaveric and composite tibial fragment rotation above and below a mid-tibial transverse osteotomy. METHODS: Twelve composite and four matched pairs of human cadaveric tibiae were randomized into either a compression group or a non-compressed dynamized group. A bi-axial servo-hydraulic testing machine applied 5Nm of internal and external torque (2Nm/s) under constant axial loads of 375N and 750N. Rotation along each tibia and at the osteotomy site was recorded from the trajectories of infrared emitting diodes rigidly attached along the tibial shaft. FINDINGS: In comparison to dynamized nails, intramedullary nail compression significantly reduced the rotation at the osteotomy site in both human (8.9 degrees reduction; P=0.007) and composite tibiae (2.5 degrees reduction; P=0.039) under 750N of axial load. A similar result was noted for simulated half-body weight loads (375N) for both composite (3.0 degrees reduction; P=0.009) and human tibiae (10.5 degrees reduction; P=0.003). INTERPRETATION: Intramedullary nail compression more effectively reduced tibial fragment rotation about a mid-tibial osteotomy than conventional dynamized intramedullary nails because intramedullary nails created more osteotomy site compression than the application of body weight to tibiae instrumented with dynamized intramedullary nails.     

Cancer patients' satisfaction with care in traditional and innovative ambulatory oncology clinics

This study examined the effects of environmental changes, such as rearranging the seating area, playing soft music, and displaying scenes of nature, on aspects of patient satisfaction, ranging from satisfaction with the physical environment and wait times to continuity of care, confidentiality, and trust in providers. Patients receiving care in a new, innovative cancer center had significantly higher satisfaction scores on the physical environment and wait time subscales than the patients receiving care in an older, traditional center. However, the 2 centers did not differ on any of the other satisfaction subscales. Implications of these findings are discussed.     

Neuromuscular reeducation versus traditional programs for stroke rehabilitation

This study compares long-term effectiveness of traditional functional retraining (TFR) with neuromuscular retraining techniques (NRT) after cerebrovascular accident (CVA). Groups of post-CVA patients from two different rehabilitation programs were matched according to early prognostic indicators. In one program NRT was emphasized while in the other the emphasis was restricted to TFR of spontaneously acquired upper extremity dexterity. Follow-up was possible in 19 of the TFR group and 20 of the NRT group who survived eight months after CVA. At least eight months post-CVA patients/families completed a telephone questionnaire regarding current functional abilities. With the single exception of self-feeding, no statistically significant differences in skill levels were found. NRT patients showed a slightly greater independence in feeding than the patients in functional retraining. It was also noted that rehabilitation hospitalization was significantly longer in the NRT group (28.57 days vs 68.3 days). The reason for this is not clear. If choice of therapeutic techniques was a contributing factor to increased lengths of stay, however, this would have major cost/effectiveness implications for program planning.     

Point system versus legal system: an innovative approach to clinical evaluation

Faced with increasing attendance and tardiness problems in an undergraduate student nursing clinical setting, the authors implemented a "point system" policy to objectively evaluate student performance. The authors discuss the policy, based on area hospital attendance point systems, and its impact.     

Single bolus versus split dose gadolinium administration in extra-cellular volume calculation at 3 Tesla

Background

Diffuse myocardial fibrosis may be quantified with cardiovascular magnetic resonance (CMR) by calculating extra-cellular volume (ECV) from native and post-contrast T1 values. Accurate ECV calculation is dependent upon the contrast agent having reached equilibrium within tissue compartments. Previous studies have used infusion or single bolus injections of contrast to calculate ECV. In clinical practice however, split dose contrast injection is commonly used as part of stress/rest perfusion studies. In this study we sought to assess the effects of split dose versus single bolus contrast administration on ECV calculation.

Methods

Ten healthy volunteers and five patients ( 4 ischaemic heart disease, 1 hypertrophic cardiomyopathy) were studied on a 3.0 Tesla (Philips Achieva TX) MR system and underwent two (patients) or three (volunteers) separate CMR studies over a mean of 12 and 30 days respectively. Volunteers underwent one single bolus contrast study (Gadovist 0.15mmol/kg). In two further studies, contrast was given in two boluses (0.075mmol/kg per bolus) as part of a clinical adenosine stress/rest perfusion protocol, boluses were separated by 12 minutes. Patients underwent one bolus and one stress perfusion study only. T1 maps were acquired pre contrast and 15 minutes following the single bolus or second contrast injection.

Results

ECV agreed between bolus and split dose contrast administration (coefficient of variability 5.04%, bias 0.009, 95% CI −3.754 to 3.772, r² = 0.973, p = 0.001)). Inter-study agreement with split dose administration was good (coefficient of variability, 5.67%, bias −0.018, 95% CI −4.045 to 4.009, r² = 0.766, p > 0.001).

Conclusion

ECV quantification using split dose contrast administration is reproducible and agrees well with previously validated methods in healthy volunteers, as well as abnormal and remote myocardium in patients. This suggests that clinical perfusion CMR studies may incorporate assessment of tissue composition by ECV based on T1 mapping.     

Attitudes of doctors toward community medicine: Differences between graduates from innovative and traditional medical schools

Background: As the importance of community medicine in undergraduate medical curricula is increasingly emphasized, it is important to measure the long‐term impact of these courses on graduates’ attitudes towards community medicine.

Purpose: To compare the attitudes of general practitioners from a community‐oriented medical school with those from a traditional undergraduate background.

Methods: We developed a valid and reliable 35 item questionnaire assessing six key areas of community medicine.

Results: We found general practitioners from the community‐oriented medical school had more positive attitudes towards community medicine overall, and towards holistic and collaborative care. General practitioners, who were younger and female, had more positive attitudes on some dimensions.

Conclusions: This study provides some evidence to support the notion that medical educators have the potential to reinforce, or shape, the attitudes that students bring to medical school.