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41.
Résumé L'utilisation de matériaux d'ostéosynthèse biodégradables a l'avantage d'éviter la réintervention pour extraire le matériel. Les biomatériaux de polymères polyglycolides ont été expérimentés sur plus de 3 600 animaux de laboratoire avant leur introduction en pratique clinique. Depuis 1984 nous les avons utilisés comme matériau d'ostéosynthèse dans près de 1 700 cas parmi lesquels 880 cas de fracture malléolaire, 226 cas d'ostéotomie en chevron pour hallux valgus, 65 cas de fracture de la tête radiale et 54 cas de fracture de l'olécrane. Parmi les 800 premiers cas traités par broches biodégradables nous avons obtenu des résultats favorables et sans incidents dans 91 pour cent des cas. Il y eut 7 cas de fixation défaillante nécessitant une réintervention. Il y a eu 7 cas d'infection superficielle et 3 cas d'infection profonde. Nous avons observé la formation d'une collection séreuse sous-cutanée sans influence sur le résultat radiologique ou clinique dans 52 cas (6,5 %). Au vue de ces résultats et compte tenu des avantages économiques et psychologiques des matériaux biodégradables (pas de réintervention), on peut penser que l'usage de biomatériaux rivalise favorablement avec l'usage de matériaux conventionnels dans certains types d'ostéosynthèse.
Utilization of biodegradable implants in the surgical treatment of fractures and osteotomies
Summary The utilization of biodegradable implants instead of metals in orthopaedic surgery abolishes the need to remove the fixation material. For this study biodegradable rods and screws of self-reinforced polyglycolide, polylactide and lactide-glycolide copolymer were developed and manufactured. The clinical introduction of these implants was preceded by thorough experimental studies with 3 600 animals. From November 1984 the developed biodegradable method of osteofixation was used in 1 700 operations. These included 880 displaced malleolar fractures, 226 chevron-osteotomy for hallux valgus, 65 displaced fracture of the radial head, 54 displaced frature of the olecranon and other fresh fractures or orthopaedic operations. In the first 800 cases operated on using self-reinforced polyglycolide rods the postoperative course was uneventful (91%). Because of failure in the fixation reoperation was needed in 7 cases. A superficial wound infection was observed in 7 cases, deep infection in 3 and transient fluid accumulation in 52 cases (6,5%). Fluid accumulation did not influence the radiological or clinical end-result. The advantages of biodegradable fixation are many-sided. There is a costbenefit and clinical capacity is free for other use, and psychological advantages must be emphasised because removal of implants is not needed. The over all results of this study were considered favourable.
  相似文献   
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The kinetics of inhaled methyl ethyl ketone (MEK) at a concentration of 200 ppm for four hours were studied in volunteers after swallowing ethanol at a dose of 0.8 g/kg. Ethanol was given either before or at the end of the exposure to MEK. The blood concentrations of MEK, 2-butanol, and 2,3-butanediol were monitored during and after the exposure. MEK concentrations in exhaled air and MEK and 2,3-butanediol concentrations in urine were also measured. Ethanol inhibited the primary oxidative metabolism of MEK and caused an increase in the blood concentrations of MEK and 2-butanol after ingestion. Ethanol ingestion, through higher blood MEK concentrations, also increased the elimination of MEK in the urine and exhaled air. Ethanol taken before exposure to MEK reduced the serum concentration of 2,3-butanediol initially but there was an increase about eight hours after the exposure. Urinary excretion of 2,3-butanediol followed the same pattern. Prior ingestion of ethanol thus seemed to interfere with the metabolism of 2,3-butanediol during and after exposure to MEK.  相似文献   
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本文采用RP-HPLC方法对紫苏油及其习用品白苏油、野苏油甘油酯进行了定性定量分析。利用HPLC分析油脂也为中药材真伪鉴别提供了一条有效途径。  相似文献   
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Within the scope of the symposium “Rescue Medicine in Germany” (held at the Reisensburg near Ulm in 2002), the need for a standardized data acquisition set for prehospital cardiac arrest patients was identified. Therefore, the working group “Emergency Medicine” of the German Society of Anesthesiology and Intensive Care Medicine (DGAI) created a nationwide data acquisition system for primary medical care in prehospital cardiac arrest patients treated with cardiopulmonary resuscitation procedures. The system is in full accordance with the “Utstein style.” Integration of this data acquisition system, for example into the “Dortmund protocol,” is providing a standardized data web base of all acquired prehospital data analyze and to compare processing and structural quality. As additional modules for this nationwide data web base system, an inhospital module “further clinical treatment” and a “long-term follow-up” module are currently in the developmental process.  相似文献   
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Learning and exams are closely interconnected. Test elements should accompany the learning process and not only serve to complete the training period. Examinations should be oriented toward the ideas learned and the forms of instruction used. However, the significance of examinations during the training period for emergency medical technicians is hardly ever addressed in the literature. All of the procedures that serve to evaluate the students’ performance are subsumed under the term “assessments.” This contribution presents the tasks of assessments and their requirements for occupational training of certified emergency medical technicians. It also offers a suggestion to develop a modern testing concept.  相似文献   
49.
During the past decade, RGD-peptides have become a popular tool for the targeting of drugs and imaging agents to alphavbeta3-integrin expressing tumour vasculature. RGD-peptides have been introduced by recombinant means into therapeutic proteins and viruses. Chemical means have been applied to couple RGD-peptides and RGD-mimetics to liposomes, polymers, peptides, small molecule drugs and radiotracers. Some of these products show impressive results in preclinical animal models and a RGD targeted radiotracer has already successfully been tested in humans for the visualization of alphavbeta3-integrin, which demonstrates the feasibility of this approach. This review will summarize the structural requirements for RGD-peptides and RGD-mimetics as ligands for alphavbeta3. We will show how they have been introduced in the various types of constructs by chemical and recombinant techniques. The importance of multivalent RGD-constructs for high affinity binding and internalization will be highlighted. Furthermore the in vitro and in vivo efficacy of RGD-targeted therapeutics and diagnostics reported in recent years will be reviewed.  相似文献   
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微小切口胆囊切除术2260例效果观察   总被引:1,自引:0,他引:1  
目的 总结微小切口胆囊切除术治疗胆道系统疾病的经验。方法 对2002-2004年连续收治的2260例胆囊、胆道系统疾病实施微小切口手术的临床观察资料进行回顾性分析。结果 本组2260例微小切口胆囊切除术的患者无一例因手术原因死亡;术后无残留小胆囊;无胆汁漏及腹腔脓肿,亦无伤口全层裂开及切口疝形成。结论 该术式损伤小、局部显露清楚、不易发生副损伤,可同时行胆总管探查术,特殊情况下可随时改变手术方式。  相似文献   
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