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51.
The fourth-generation centrifugal blood pump 总被引:1,自引:0,他引:1
The NEDO Gyro permanently implantable (PI) centrifugal blood pump has been developed as a simple, durable, centrifugal blood
pump without a complex magnetic suspension system. In vitro studies were performed using a Gyro PI pump with the transparent
pump housing in a mock circuit. These studies revealed that the impeller transfers to a floating or a top contact condition,
which was dependent on the revolutions per minute (RPM). This pump can be easily converted from a left ventricular assist
device (LVAD) to a right ventricular assist device (RVAD) by simply adding a spacer between the pump and the actuator. In
order to optimize the impeller suspension for the LVAD and RVAD, spacers of the proper thickness are inserted between both
of the pumps and the actuators to regulate the magnetic force. Two Gyro PI pumps were implanted in a bovine model in a 3-month
biventricular assist device (BVAD) animal study. This experiment was electively terminated 90 days after implantation. All
of the parameters, including pump flow rate, power consumption, and plasma free hemoglobin, were in acceptable ranges. No
thrombus formation was observed in either pump. Antithrombogenesis and effectiveness were demonstrated in this animal study.
The NEDO Gyro PI pump is ready to move on to the 3-month preclinical system evaluation.
Received: February 28, 2002 / Accepted: May 30, 2002
Acknowledgment The New Energy and Industrial Technology Development Organization (NEDO) under the Ministry of Economy, Trade and Industry
of Japan financially supported this project.
Correspondence to:S. Ichikawa 相似文献
52.
目的分析应用Orthofix-微型器治疗第一掌骨基底部Bennett骨折的临床疗效。方法收集2009年1月~2013年1月我院31例采用Orthofix-微型器治疗的第一掌骨基底部Bennett骨折患者。记录患者年龄、性别等基线资料,以及术后上肢臂、肩、手功能调查量表(Disabilities of the arm,shoulder and hand,DASH)评分,随访终末期采用指总关节活动度(Total action movement,TAM)评分。结果随访6~24个月,平均14.4月,手术时间为18~40分钟,平均29.1分钟,术中出血量10~30m L,平均14.5m L。术后3月、术后6月及终末期DASH评分之间比较,差异均有统计学意义(0.05)。随访终末期,其中26例解剖复位,5例骨折对线良好,TAM评分优22例,良7例,差2例。随访期间未发生桡神经浅支损伤、钉道感染等并发症。结论 Orthofix-微型外固定器治疗Bennett骨折操作简单、疗效满意。 相似文献
53.
刘秀珍 《生物医学工程学杂志》2007,24(6):1256-1259
为提高诊断X线机的诊断质量,促进放射防护工作的开展,根据"国际辐射单位和测量委员会"(International Commission on Radiological Units and Measurements,ICRU),"国际放射防护委员会"(International Commission on Radiation Protection,ICRP)关于辐射对人体的损害之划分标准,作者对岛津制作所90年代中期生产的XEB150L-20型500mA X线机按照国家规定的要求及有关标准,分别对辐射空气释动能率,半价层,输入量重复性,输出量线性,高对比分辨率,光野与照射野一致性及X线管的焦点等参数进行了测试。分析了测试的数据与结果,并进行了简要的评价。 相似文献
54.
Platteau P Laurent E Albano C Osmanagaoglu K Vernaeve V Tournaye H Camus M Van Steirteghem A Devroey P 《Human reproduction (Oxford, England)》2003,18(6):1200-1204
BACKGROUND: A pen device, similar to an insulin pen, has been recently marketed for the administration of follitropin beta in cartridges. A randomized controlled trial was performed to compare the efficacy and convenience of this pen device delivering follitropin beta with a conventional syringe delivering follitropin alpha. METHODS: A total of 200 patients needing IVF/ICSI treatment and willing to self-inject were enrolled in the study. All subjects had ovarian stimulation according to a long protocol and were randomized to the pen or the conventional syringe group during down-regulation by means of a computer-generated randomization list using random numbers. Patients were asked to fill in a daily local tolerance book after each injection. On the day of hCG the patients scored a Visual Analogue Scale (VAS) for pain and convenience. RESULTS: The average duration, total dose of recombinant FSH and number of cumulus oocyte complexes retrieved were 10.8/12.0 days (P = 0.001), 1880/2226 IU (P < 0.001) and 15.2/13.1 respectively in the pen device and conventional syringe groups; the presence of pain after the daily injection was significantly higher in the conventional syringe group (P = 0.027); the visual analogue scale score was similar for pain but significantly more convenient for the pen device (P < 0.001). The live birth rate per embryo transfer was 32.9 and 34.4% respectively in the pen device and conventional syringe groups. CONCLUSIONS: Self-injection with the pen device is safe and easy, more convenient and less painful for the patient, requires less FSH and shortens the treatment duration. 相似文献
55.
目的:总结抓髌骨器治疗髌骨骨折的体会。方法:髌骨内侧小切口,清理关节内瘀血,手指探入,协助整复,引导爪钩,固定骨折,早期进行功能锻炼。结果:共治疗各类型骨折43例;骨折全部于手术后6-8周愈合,优良率97.7%。结论:抓髌器治疗髌骨骨折具有创伤小、愈合快、功能恢复好,不需再次手术等优点,是治疗髌骨骨折首选方法。 相似文献
56.
Mohammad Sotoudeh Shila Jalali Shunichi Usami John Y-J. Shyy Shu Chien 《Annals of biomedical engineering》1998,26(2):181-189
The objective of this study is to design a new apparatus to allow the control of the magnitude and frequency of dynamic stretch applied uniformly to cells cultured on a silicon elastic membrane. The apparatus is designed to produce equi-biaxial dynamic stretches with area changes ranging from 0% to 55% and frequencies ranging from 0 to 2 Hz. Homogeneous finite strain analysis using triangles of markers was performed to compute the symmetric two-dimensional Lagrangian strain tensor on the membrane. Measurements of strain in both static and dynamic conditions showed that the shear component of the strain tensor (Erc) was near zero, and that there was no significant difference between radial (Err) and circumferential (Ecc) components, indicating the attainment of equi-biaxial strain. Bovine aortic endothelial cells were transiently transfected with a chimeric construct in which the luciferase reporter is driven by TPA-responsive elements (TRE). The transfected cells cultured on the membrane were stretched. The luciferase activity increased significantly only when the cells were stretched by 15% or more in area. Cells in different locations of the membrane showed similar induction of luciferase activities, confirming that strain is uniform and equi-biaxial across the membrane. © 1998 Biomedical Engineering Society.
PAC98: 8780+s, 8745-k, 8722-q 相似文献
57.
Zhu P Liu X Luo H Gu Z Cheng J Xu R Lian S Wu S Wang J 《Human reproduction (Oxford, England)》1999,14(4):970-975
Thirty-four women bearing a levonorgestrel-releasing intrauterine device, 20 micrograms/day (LNG-IUD-20), for 12-15 months were recruited. Endometrial biopsies were collected during the late proliferative phase of the cycle (on cycle days 10-12) before (control) and after the use of the IUD for 12 months, and assayed for oestrogen receptors (ER) and progesterone receptors (PR). An immunohistochemical technique with the peroxidase-antiperoxidase detection system (PAP method) was employed. D75 and JZB39 were the primary antibodies for ER and PR respectively. The immunostaining semiquantitative analysis was performed with a computerized microscope image processor, and expressed as 'grey value'. Both endometrial ER and PR populations were significantly lower after insertion of the IUD (P < 0.01) than in control biopsies. The intensity of nuclear staining and the percentage of positively stained cells for ER and PR in women with LNG-IUD were each about 50% of those in control biopsies. The results suggested that LNG released locally from the IUD has a depressive action on the ER and PR, which may contribute to the contraceptive effectiveness of this type of IUD and also to the possible causes of LNG-IUD-induced irregular bleeding and amenorrhoea. 相似文献
58.
Takeshi Komoda MD Thorsten Drews MD Hans B. Lehmkuhl MD Roland Hetzer MD PhD 《Journal of artificial organs》2006,9(1):29-33
The Eurotransplant (ET) allocation algorithm, newly implemented in 2000, gives priority for heart transplantation (HTx) to
patients with high urgency (HU) status, but now this status is rescinded upon ventricular assist device (VAD) implantation
and only regained if severe complications occur during mechanical circulatory support (MCS). We studied the effects of this
change on the patients in our institute who were waiting for HTx with MCS. The median duration of MCS until HTx in adult patients
gradually increased from 3.1 months in 1994, reaching a peak of 16.7 months in 2000, and then gradually decreased to 6.0 months
in 2003. Among the patients with VAD implantation as a bridge to HTx, two patients were on MCS for more than 1 year (the longest
duration of MCS being 1.6 years) at the end of 1999, and this figure increased to nine patients and a maximum MCS duration
of 3.7 years at the end of 2003. These data imply that the patients in whom a complication occurred in the early phase of
MCS and who had overcome this complication underwent HTx early with HU status, and those who were stable during MCS waited
a long time for HTx. Furthermore, the number of patients in the latter group is increasing. The new allocation algorithm imposes
on patients with MCS waiting for HTx who are relatively young and free from complications and serious coexisting disease,
very long-term MCS without an end to VAD bridging, which is almost equivalent to destination therapy.
Part of this paper was presented at the 42nd JSAO Conference (Tokyo, October 5–7, 2004) 相似文献
59.
Simulation study of the Hemopump as a cardiac assist device 总被引:2,自引:0,他引:2
A dynamic model was developed for a Hemopump that withdraws blood from the left ventricle and discharges it to the aorta through
a miniature axial-flow pump. Incorporation of the Hemopump model in a previously established model for the canine circulatory
system enabled the effects of the Hemopump on various haemodynamic variables of the circulatory system to be studied, and
the benefit of the Hemopump to the failing heart was investigated. In addition, the influence of the physiological status
of the right ventricle on the Hemopump performances was examined, and the synchronous and non-synchronous operations of the
Hemopump were compared. Results verified that the Hemopump assists the failing heart by increasing the oxygen supply, while
reducing the oxygen consumption of the heart through a reduction in the workload of the left ventricle. These beneficial effects
were enhanced when the pump's rotation speed was increased. When pump speed was increased from 17000 to 23000 revolutions
min−1, the oxygen supply increased 101%, and the oxygen consumption decreased 60%. However, when the pump rotation speed was too
high, the inflow to the pump could be impaired and the pump performance could be negatively affected. Predications from the
model were in good agreement with the results previously obtained in animal experiments and in vitro measurements. 相似文献
60.
Fertility outcome after ectopic pregnancy and use of an intrauterine device at the time of the index ectopic pregnancy 总被引:3,自引:0,他引:3
Bernoux A Job-Spira N Germain E Coste J Bouyer J 《Human reproduction (Oxford, England)》2000,15(5):1173-1177
Fertility after ectopic pregnancy (EP) was investigated in a non-selected population taking into account intrauterine device (IUD) use at the time of the EP. Between January 1992 and June 1996, 647 women listed in the EP register of Auvergne (France) were followed up. The analysis included only the 328 women who were seeking to become pregnant: 23 women using IUD at the time of the index EP (IUD users) and 305 IUD non-users. Among IUD users, there was no recurrence of EP, and the 1 year cumulative rate was 87% [95% confidence interval (CI): 73-100%] for intrauterine pregnancies and 86% (95% CI: 72-100%) for deliveries. Among IUD non-users, the 2 year cumulative rate for recurrence of EP was 28% (95% CI: 17-39%), and the 1 year cumulative rates were 60% (95% CI: 53-66%) for intrauterine pregnancies and 44% (95% CI: 38-56%) for deliveries. The adjusted intrauterine pregnancy rate of IUD users was not significantly different from that of IUD non-users. However, IUD non-users had more miscarriages, so their delivery rate was lower. 相似文献