双联滑移齿轮轴向排列最小宽度的剖析

本文阐述了双联滑移齿轮在适当传动出情况下,轴向移动一个齿轮宽度就可以进行变速的可行性及适用场合。而一般书籍介绍,双联滑移齿轮的变速轴向至少移动二个齿宽。     

用线切割机床加工椭圆齿轮的编程方法

介绍了在数控线切割机床上加工椭圆齿轮时，齿的位置和齿形的确定方法。提出了用线切割加工椭圆齿轮时用非标准模数优于用标准模数的观点。     

齿轮式髓内针拔取器的研制与应用

髓内针固定术是临床上治疗股骨干骨折常用术式,当需拔取时,现仍多用打拔器,其支点为髋臼。因颈干角平均为127°,因此其支点与力点形成26°±分力,故拔取力量极为不足,经常遇到拔取困难,尤其对已固定多年或髓内针发生一定程度弯曲时,更难予以拔取或根本无力拔取,使手术处于极为被动局面。为此我们研制了齿轮式髓内针拔取器,经临床应用,功能极佳,报告如下:1　结构齿轮式髓内针拔取器　主要由①立柱、②齿条、③扳手、④托板、⑤挂钩、⑥支点固定帽等组成。图1,2。图1、齿轮式髓内针拔取器示意图图2、齿轮式髓内针拔取器实物照2　使用方法　病…     

游离齿突小骨及寰枢椎不稳

游离齿突小骨(Os odontoideum)是齿突畸形中最常见的一种，常导致寰枢椎不稳，引起脊髓压迫，严重者可导致瘫痪．本文综述了游离齿突小骨的发生原因、导致寰枢椎不稳的客观测量指标、齿突周围反应性软组织增生以及脊髓压迫程度等方面．以协助诊断、指导治疗。     

肛管血供分布的局部解剖学

近期推测肛裂是一缺血性溃疡，由于内括约肌（IAS）痉挛和肛管后正中线血供不良所致。Kloster－112llfell曾对直肠下动脉的局部解剖进行1”研究．发现有两种不同的血供分布：在回SK病例．胆管前后止中线有直肠下动脉分支充分供应．而另85／的后上中线处血供不良。作者观察肚膜下间隙和齿线上下方lAS的后、外侧和前象限的小动脉密度。自尸体整块切下直肠和胆管．沿前中线剖开标本．定位齿线．在齿线上下方各Icm间距横切肛管全长．分别固定在特种蜡中．切片厚IOpm．取每一蜡块的第25切片固定在玻片上．用HE染色。从每。张切片观察一张切…     

肛内乳头状囊性汗腺瘤1例

1病案 患者女,28岁,因“肛门疼痛伴坠胀不适半个月”于2010年5月1日以“肛裂、肛乳头肥大、直肠肿物”诊断收入院。T：36．8℃,P：80次／分,R：20次／分,BP：14．7／9．3kPa。专科检查：肛门截石位6点肛缘凹陷,齿线处肛管皮肤见裂口,肛乳头增生肥大。肛门指诊齿线上2．5cm处直肠黏膜下触及直径约1．5cm半球形肿物,质韧囊性,表面光滑,     

Dens双螺钉固定齿突骨折

齿突骨折占颈椎骨折的10％～15％．其中AndersonⅡ型(通过齿突基底部)的骨折占齿突骨折的2／3。此型骨折常出现明显的寰枢椎不稳，易引起神经症状，且不愈合率高，常需内固定治疗。如采用寰枢椎后路融合术，将影响40％～50％一的颈椎旋转动度。而采用齿突螺钉直接内固定，不但可以保留     

1例枢椎齿突骨折经口咽前路齿突截骨矫形后路复位内固定融合术手术配合

对1例枢椎齿突骨折C1-2、脱位伴不全瘫的患者，行经口咽前路齿突截骨矫形、后路复位内固定融合术．术前予心理支持、口腔准备及呼吸训练，术中熟练地配合．术中及术毕保持正确体位。结果手术顺利．术后3个月复查．内固定无松动移位，植骨融合良好，四肢运动感觉正常。提示优质的手术配合是手术成功的重要环节。     

单枚螺钉前路固定AndersonⅡ型齿状突骨折

目的 回顾分析18例齿突骨折前路螺钉固定术，探讨手术的安全性和疗效。方法 1998年12月至2004年2月，前路螺钉固定治疗创伤性AnclersonⅡ型齿突骨折脱位18例，男15例，女3例，平均42．2岁。所有病例术前均行颅骨牵引，受伤后平均5d内行前路齿突螺钉固定手术，术后颈围保护6周。进行了定期的临床和X线检查随访。结果 平均随访15．8个月。得到随访的17例骨折全部骨性愈合，无术中及术后并发症，无内固定螺钉松动，移位或断裂。结论 前路螺钉固定治疗齿突骨折既可提供良好的稳定性又能保留寰枢关节活动性，骨折愈合率较高，并发症低，是治疗AidersonⅡ型齿突骨折较好的方法。     

寰椎后弓椎板钩联合枢椎椎弓根螺钉固定治疗Ⅱ型齿突骨折

目的评估寰椎后弓椎板钩联合枢椎椎弓根螺钉固定植骨融合治疗Ⅱ型齿突骨折的疗效。方法2004年3月-2007年3月对13例Ⅱ型齿突骨折患者以寰椎后弓椎板钩联合枢椎椎弓根螺钉固定自体髂骨植骨融合术进行治疗，其中6例伴脊髓受损症状。结果术中未发生椎动脉和脊髓损伤；平均随访时间为18个月（6—32个月）；未发生内固定物松动、断裂。所有患者寰枢椎均融合。6例脊髓受损患者术前JOA评分为10．1分（9．2～11．8分），术后2周JOA评分为15．6分（15．2～16．8分）。结论寰椎后弓椎板钩联合枢椎椎弓根螺钉固定植骨融合术治疗Ⅱ型齿突骨折是一种安全有效的方法。     

A pilot survey of Southeastern firefighters: Safety practices,use of protective gear,and injury

IntroThere were over 60 firefighter line of duty deaths and roughly 30,000 injuries in the United States in 2016. Modern thermoprotective gear has reduced the risks firefighters face from both thermal and inhalation injury, but must be used properly to be effective. The purpose of this study is to examine gear use and associated injury in firefighters.MethodsSurveys were distributed with questions about demographics, gear usage, and maintenance practices. If previously injured, firefighters described the injury, treatment, and recovery.ResultsOf the 50 surveys distributed, 37 were returned (72%). A majority of respondents (70%) reported wearing incomplete gear. Those who reported injury were more likely to have omitted gear (81% vs 45%). For all respondents, the items most commonly omitted were hood (58%), gloves (22%), and earflaps (22%). Regular cleaning of gear was not practiced by 39% of burned respondents and 46% had not had their gear sized within 2 years. Serious burns were reported by 41% of respondents. Mean burn size was 7% total body surface area (TBSA), and 11% reported self-treating their burns, including 63.5% who continued to work despite suffering a 2nd or 3rd degree burn injury. Only 17% were treated at a burn center, and this group missed anywhere from two shifts to 8 months of work.ConclusionsFirefighters risk injury by omitting gear and not adhering to National Fire Protection Association (NFPA) guidelines on gear sizing, maintenance, and station wear. Firefighters also frequently self-treat serious burns despite unique considerations regarding re-injury. National trends related to gear use and injury risk should be studied further, and standards should be developed for ensuring safe return to work.     

Skateboard and in-line skate fractures: a report of one summer's experience.

During a 5 month period, 26 skateboarding and 10 in-line skating fractures were seen at our institution. The radius was the most commonly injured bone in both groups. Forty-two percent of skateboard fractures required reduction and another 16% required operative intervention. Epiphyseal fractures occurred in 42% of the skateboard riders who were skeletally immature. A greater proportion of high-energy fracture patterns was recorded in contrast to earlier reports. Also, a trend towards injuries occurring on the street, as opposed to home, has been noted. Skateboard riders continue to shun protective gear and hitting a surface irregularity is the most common cause of fall. In-line skaters, on average, wear more protective gear and are more likely to continue riding after their injury. Routine protective gear and avoidance of street riding should be encouraged. Instructions stressing balance and control as opposed to showmanship are recommended. Caution is given to first time in-line skaters, as this appears to be an injury-prone period.     

斑块磨削和改良Nesbit技术治疗阴茎硬结症

目的 :探讨斑块磨削和改良Nesbit技术治疗阴茎硬结症的疗效。　方法 :11例阴茎硬结症病人行斑块磨削和改良Nesbit技术治疗 ,并进行随访。　结果 :11例均获得了满意的治疗效果。 9例术前无勃起功能障碍者术后均获得了满意的性生活 ;8例伴有阴茎勃起时弯曲者中 ,2例由于斑块范围过大 ,术中矫正不彻底 ,仍残留有轻微弯曲 ;5例伴有勃起疼痛的病人术后均获改善 ,仅 1例有轻微的间歇疼痛 ;但以上情况均不影响性生活。　结论 :斑块磨削和改良Nesbit技术治疗阴茎硬结症操作方便 ,近期治疗效果好 ,术后并发症少 ,复发率低 ,远期疗效需进一步观察     

Experience in treatment of Peyronie＇s disease by plaque thinning with carbide burs and improved Nesbit technique

Objective: To study the efficacy of plaque thinning with carbide burs and improved Nesbit technique in the treatment of Peyronie's disease. Methods: Follow-up studies were made on 11 patients with Peyronie's disease treated by plaque thinning with carbide burs and improved Nesbit technique. Results: Satisfactory results were obtained in all the cases. Nine cases without previous ED could now complete the sexual intercourse. Of the 8 cases with penile curvature, only 2 were not completely corrected and of the 5 cases with erectile pain, only 2 still had slight intermittent pain during erection. However, in these patients with residual curvature and slight intermittent pain, their sexual life was not affected. Conclusion: Plaque thinning with carbide burs and improved Nesbit technique for the treatment of Peyronie' s disease have many advantages, including easy manipulation, good short-term results, few complications and rare recurrence, but its long-tern results are not yet clear.     

Impact of dedicated skate parks on the severity and incidence of skateboard- and rollerblade-related pediatric fractures

Dedicated skate parks have led to an increase in pediatric fractures referred to the authors' unit. The authors performed a prospective analysis of all patients presenting to their unit with fractures sustained while Rollerblading or skateboarding over a 5-month period. Epidemiologic data, user experience, wearing of protective gear, place of injury, and mechanism of injury were collected. Fracture type and its treatment were also recorded. The findings indicated that the use of skate parks is associated with a significant increase in the severity of fracture. This was not related to mean length of experience, age, or sex. The use of skate parks had an increased relative risk of 8.35 for fractures requiring manipulation or invasive orthopedic treatment. Only 5% of children were wearing some form of limb/joint protective gear. The authors believe there should be closer supervision and training of children and more emphasis on limb protective gear. The current high incidence of significant skate park injuries will otherwise continue, with implications for the well-being of these children and the burden on the healthcare system.     

Antichemical protective gear prolongs time to successful airway management: a randomized, crossover study in humans

BACKGROUND: Airway management is the first step in resuscitation. The extraordinary conditions in mass casualty situations impose special difficulties in airway management, even for experienced caregivers. The authors evaluated whether wearing surgical attire or antichemical protective gear made any difference in anesthetists' success of airway control with either an endotracheal tube or a laryngeal mask airway. METHODS: Fifteen anesthetists with 2-5 yr of residency and wearing either full antichemical protective gear or surgical attire intubated or inserted laryngeal masks in 60 anesthetized patients. The study was performed in a prospective, randomized, crossover manner. The duration of intubation/insertion was measured from the time the device was grasped to the time a normal capnography recording was obtained. RESULTS: Endotracheal tubes were introduced significantly (P < 0.01) faster when the anesthetist wore surgical attire (31 +/- 7 vs. 54 +/- 24 s for protective gear), but the mean times necessary to successfully insert laryngeal masks were similar (44 +/- 20 s for surgical attire vs. 39 +/- 11 s for protective gear). Neither performance failure nor incidences of hypoxemia were recorded. CONCLUSIONS: This first report in humans shows to what extent anesthetists' wearing of antichemical protective gear slows the time to intubate but not to insert a laryngeal mask airway compared with wearing surgical attire. Laryngeal mask airway insertion is faster than tracheal intubation when wearing protective gear, indicating its advantage for airway management when anesthetists wear antichemical protective gear. If chances for rapid and successful tracheal intubation under such chaotic conditions are poor, laryngeal mask airway insertion is a viable choice for airway management until a proper secured airway is obtainable.     

基于动载荷的齿轮传动系统瞬态弹流润滑分析

综合考虑了齿轮传动系统振动影响、润滑流体的可压缩性 ,以及滑动速度和曲率半径随时间和坐标的变化 ;进行了动载荷下的直齿轮传动弹流润滑数值分析 ,获得了齿轮传动沿啮合线的中心油膜及摩擦系数的分布 ,并给出了 7个特殊啮合点上的压力分布及油膜形状 .     

The Helmholtz Total Artificial Heart Labtype

Abstract: To perform the first experimental tests for validation of a new gear unit concept, the pump chamber, diaphragm, and pusher plate design of an orthotopic electromechanical total artificial heart (TAH) (Helmholtz Labtype) was manufactured. In its early stage of development, it provides some of the most important features of the conceptual final artificial heart. The new gear unit transforms a uniform unidirectional rotational motor movement into translatory pusher plate movements, with resting phase in the end–diastolic position, and the angled pump chamber orientation determines the available space for the motor and gear unit. Furthermore, this labtype provides flexibility with regard to use of different types of structural parts for experimental investigations. The first in vitro test results, obtained with specially designed circulatory mockloops that simulate physiological preload and afterload conditions, are presented. They comprise pressure and flow generation, motor performance, efficiency, and energy consumption. The results prove the feasability of the new gear unit concept for an electromechanical artificial heart and allow a reliable determination of the necessary performance of the future brushless DC motor for the first in vivo TAH model.     

Antichemical Protective Gear Prolongs Time to Successful Airway Management: A Randomized, Crossover Study in Humans

Background: Airway management is the first step in resuscitation. The extraordinary conditions in mass casualty situations impose special difficulties in airway management, even for experienced caregivers. The authors evaluated whether wearing surgical attire or antichemical protective gear made any difference in anesthetists' success of airway control with either an endotracheal tube or a laryngeal mask airway.

Methods: Fifteen anesthetists with 2-5 yr of residency and wearing either full antichemical protective gear or surgical attire intubated or inserted laryngeal masks in 60 anesthetized patients. The study was performed in a prospective, randomized, crossover manner. The duration of intubation/insertion was measured from the time the device was grasped to the time a normal capnography recording was obtained.

Results: Endotracheal tubes were introduced significantly (P < 0.01) faster when the anesthetist wore surgical attire (31 +/- 7 vs. 54 +/- 24 s for protective gear), but the mean times necessary to successfully insert laryngeal masks were similar (44 +/- 20 s for surgical attire vs. 39 +/- 11 s for protective gear). Neither performance failure nor incidences of hypoxemia were recorded.