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61.
Development of rotary blood pump technology: past, present, and future   总被引:5,自引:0,他引:5  
Even though clinical acceptance of a nonpulsatile blood flow was demonstrated almost 45 years ago, the development of a nonpulsatile blood pump was completely ignored until 20 years ago. In 1979, the first author's group demonstrated that completely pulseless animals did not exhibit any abnormal physiology if 20% higher blood flows were provided to them. However, during the next 10 years (1979-1988), minimum efforts were provided for the development of a nonpulsatile, permanently implantable cardiac prosthesis. In 1989, the first author and his team at Baylor College of Medicine initiated a developmental strategy of various types of nonpulsatile rotary blood pumps, including a 2-day rotary blood pump for cardiopulmonary bypass application, a 2 week pump for ECMO and short-term circulatory assistance, a 2 year pump as a bridge to transplantation, and a permanently implantable cardiac prosthesis. Following the design and developmental strategy established in 1989, successful development of a 2-day pump (the Nikkiso-Fairway cardiopulmonary bypass pump) in 4 years (1989-1993), a 2 week pump (Kyocera gyro G1E3 pump) in 6 years (1992-1998), and a bridge to transplant pump (DeBakey LVAD-an axial flow blood pump) in 10 years (1988-1998) was made. Currently, a permanently implantable centrifugal blood pump development program is successfully completing its initial Phase 1 program of 5 years (1995-2000). Implantation exceeded 9 months without any negative findings. An additional 5 year Phase II program (2000-2005) is expected to complete such a device that will be clinically available.  相似文献   
62.
Kim WG  Na MH  Kim JH 《Artificial organs》2000,24(9):729-733
An effective in vitro protocol for the investigation of thrombogenicity can provide many advantages in the development of mechanical circulatory assist devices. Strict avoidance of air contact with blood recently was proposed for reliable in vitro evaluation. This study was performed to confirm the necessity of avoidance of air contact for the in vitro test of thrombogenicity in a rotary pump. Two sets of mock circuits with the same rotary blood pumps, reservoirs, and connecting tubes were made. In one system, blood came in contact with air while the other did not. The test blood was heparinized at the dose of 1 IU per 1 ml of blood. The tests were terminated at an activated coagulation time of 1.5 times the control value. The levels of hematocrit, platelet, factors VIII and XII, fibrinogen, thromboxane B2, and plasma-free hemoglobin were measured during the procedures. After the experiments, the thrombi formed were observed, measured, and compared with those formed in in vivo circumstances. The tests were repeated 12 times. There were no statistically significant differences between the 2 groups in hematologic parameters and the amounts of thrombi formed. The thrombi observed in both groups showed the same pathologic findings as those formed in vivo with the exception of intermittent multiple air bubbles found in thrombi of the air-contact group. In conclusion, the effect of air contact in the in vitro investigation of thrombogenicity was negligible while the proposed in vitro test models of thrombogenesis in the mechanical circulatory assist device proved to be reliable.  相似文献   
63.
Research of the distributed artificial heart is important not only to acquire the means of individual organ perfusion but also to clarify the characteristics of the organ and the mechanism of blood distribution. To investigate the distributed artificial heart, the miniature undulation pump was developed. The outer diameter and the thickness of the developed pump were 38 mm and 11 mm, respectively. The priming volume of the pump was 3.2 ml. The total size including the motor unit was 38 mm in diameter and 32 mm in length. The total weight was 67.5 g. The total volume was 27.5 ml. The pump was driven with pulse width modulation by using a 1 chip motor controller. More than 5 L/min of continuous output could be obtained. The results showed that the developed miniature undulation pump system had enough performance for individual organ perfusion.  相似文献   
64.
目的:对晚期上皮性卵巢癌患者行手术及术中皮下埋藏腹腔化疗泵联合化疗,并对其疗效进行评价,以期对治疗提供帮助。方法:1995年8月~1997年8月收治的卵巢癌患者中24例行手术及术中皮下埋藏化疗泵,术后采用CAP方案联合化疗。顺铂50~70mg/m^2腹腔灌注,阿霉素40~60mg/m^2、环磷酰胺600~800mg/m^2静脉注射,平均4~5周为一疗程,总疗程6~12个。结果:Ⅲ期患者总有效率为77.8%;3年生存率50.0%,5年生存率25.0%。结论:彻底的手术加腹腔泵灌注腹腔化疗及静脉化疗是治疗晚期上皮性卵巢癌的有效途径,可提高患者的生活质量及生存率。  相似文献   
65.
甘精胰岛素强化治疗2型糖尿病的研究   总被引:2,自引:0,他引:2  
目的 观察甘精胰岛素治疗2型糖尿病患者的降糖效果和安全性。方法 2 7例2型糖尿病伴高血糖(FPG≥1 1mmol/L)患者随机分为A、B 2组进行强化胰岛素治疗,A组为甘精胰岛素治疗组(n =1 3) ;B组为胰岛素泵治疗组(n =1 4 )。2组治疗目标末梢血糖值为空腹≤7.0mmol/L和餐后2h血糖≤1 1 .1mmol/L。结果 2组患者都达到目标血糖值,血糖达标时间无差异,低血糖发生率无差别(P均>0 .0 5 )。结论 甘精胰岛素强化治疗可以良好地控制高血糖,且低血糖发生率低。  相似文献   
66.
便携式输液设备的研制   总被引:2,自引:0,他引:2  
本文介绍一种由8031单片机控制的便携式输液设备,阐述了其原理和组成,它可以自动控制输液速度和输液量,具有报警功能,成本低但性能好,可以广泛应用于临床输液以及药品成分分析等场合。  相似文献   
67.
目的评价胰岛素泵连续皮下输注(CSII)和静脉连续胰岛素输注(CVII)在糖尿病酮症治疗中的疗效差异。方法120例糖尿病酮症患者分为两组,CSII组和CVII各60例,观察两组不同方法的治疗效果。结果两组治疗后血糖明显下降,尿酮体均能恢复正常,CSII组优于CVII组,差异有统计学意义(P<0 05);CSII组平均胰岛素用量为(42.5±6.3)U/d明显少于CVII组(57.8±6.6)U/d(P<0 05);CSII组尿酮体恢复正常所需时间为(18.5±5.9)h明显短于CVII组(39.8±8.4)h(P<0 01);CSII组低血糖发生率为(0.41±0.13)次/例,显著低于CVII组的(0.96±0.45)次/例(P<0 05)。两组均无死亡病例。结论CSII模拟胰岛素的生理分泌模式,能更快、更有效地纠正代谢紊乱,控制高血糖,提高生活质量。  相似文献   
68.
化学发光仪中,碱泵系统提供的碱性辅助试剂是被测物反应结束后产生化学发光的必要条件,碱泵加量精度下降,会影响测量结果的准确性。质量控制的方法分为,碱泵加液量精度测试和碱泵系统清洗以及碱泵的修复。  相似文献   
69.
盐酸昂丹司琼渗透泵片的制备与体外释放   总被引:4,自引:1,他引:4  
郑杭生  毕殿洲 《药学学报》2005,40(12):1080-1084
目的制备盐酸昂丹司琼渗透泵型控释片剂(OND-OPT)并考察体外释药特性。方法以锅包衣法制备OND-OPT。通过释放度试验筛选处方并考察OND-OPT的释放特性;通过均匀设计试验建立持续释药时间与衣膜厚度、衣膜中PEG含量和释药孔孔径的关系;考察OND-OPT的释药机制。结果释药孔朝向对不含HPMC的制剂释药有明显影响,而对含HPMC的制剂释药无影响。持续释药时间与衣膜厚度和衣膜中PEG含量有关,与释药孔孔径无显著关系。OND-OPT主要以渗透泵机制释放药物。结论通过调节衣膜厚度和衣膜中PEG含量,OND-OPT可以实现理想的药物控制释放。  相似文献   
70.
胰岛素泵在肝移植术后糖代谢异常的应用研究   总被引:1,自引:0,他引:1  
目的探讨肝移植围手术期糖代谢异常的不同处理方法。方法肝移植手术后糖代谢异常患者27例,随机分为连续皮下胰岛素输注组(Continuous subcutaneous insulin infusion,CSII)与多次皮下注射胰岛素组(Multiple daily subcutaneous injection,MDSI)。对两组患者住院期间的血糖控制情况、血糖达标时间、院内感染率、伤口愈合时间、胰岛素用量、低血糖的发生率以及术后半年的糖代谢状态进行比较。结果两组患者血糖均可以达到目标值,CSII组较MDSI组每天胰岛素用量少,血糖达标时间短,切口愈合时间短,院内感染率低。两组患者术后半年的糖代谢状态无显著差异。结论对肝移植术后糖代谢异常的控制,胰岛素泵较传统的多次皮下注射胰岛素更有优势。  相似文献   
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