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91.
研究深低温停循环(DHCA)与逆行脑灌注(RCP)时脑组织自由基的变化。健康杂种犬14只,随机等分为DHCA组和RCP组,在停循环前(A点)、DHCA/RCP30分(B点)、DHCA/RCP60分(C点)DHCA/RCP90分(D眯)和复温再灌注30分(E点)取脑皮层lg,检测丙二醛(MDA)和超氧化物歧化酶(SOD)水平。结果见两组在A点MDA和SOD无差别。在B、C、D、E点,DHCA组MDA 相似文献
92.
为了探讨常温体外循环下采用缺血预调行心肌保护的研究,通过建立犬的常温体外循环全心缺血预调模型,旨在探讨心内直视手术缺血预调保护心肌的可能性。预调组采用升主动脉阻断5分钟,放开10分钟,反复三次的方式预调心脏;对照纽简单并行循环45分钟,而后两组均接受30分钟缺血和60分钟再灌注。结果显示,预调组室颤发生率低(16.7 VS 83.3%P=0.04),无再灌注心律失常(0 VS66.7%P=0.03),心肌ATP消耗减慢(4.69 1.050 VS 2.35±0.86μmol/g wet wt P<0.01),乳酸积累减少(4.49±0.86 VS 9.80 5.53mg/g wet wtP<0.05),心肌细胞超微结构损伤轻。结论:常温体外循环下应用缺血预调保护犬的心肌是可行而有效的。 相似文献
93.
Duncan W. Blake Roger G. Evans John Ludbrook Oscar U. Petring 《Clinical and experimental pharmacology & physiology》1994,21(5):383-396
1. Eight conscious rabbits were repeatedly subjected to progressive reduction in central blood volume by gradually inflating a thoracic inferior vena caval-cuff so cardiac index (CI) fell at a constant 8.5% of baseline/min. 2. Caval-cuff inflations were performed after 10 min exposure to 100, 21, 12–14 and 8–10% O2, with and without the addition of 3–4% CO2, in randomized order. 3. The haemodynamic response to progressive reduction in central blood volume was biphasic. In Phase I, systemic vascular conductance index (SVCI) fell linearly, supporting mean arterial pressure (MAP). When CI had fallen to a critical level, Phase II occurred in which SVCI rose abruptly, MAP plummeted and respiratory drive progressively increased. 4. During Phase I, there were independent linear relationships between Pao2 (but not Pao2) and the rates at which SVCI and MAP changed during the progressive fall of CI. The higher the level of Pao2, the greater was the rate of fall of SVCI and the less the rate of fall of MAP. 5. There was an inverted U-shaped effect of Pao2, on the level of CI at which Phase II occurred: (a) during hyperoxia (100% O2), Phase II occurred later than during normoxia (21% O2); and (b) across the normoxic and hypoxic gas mixtures (21–8% O2, with and without added CO2), there was an independent linear relationship between Pao2 (but not Pao2 or Pao2×Pao2) and the level of CI at which Phase II occurred. That is, the lower the level of Pao2, the later was the onset of Phase II. This interaction is best explained by an increased level of central sympathetic vasoconstrictor drive during hypoxia. 相似文献
94.
下腰痛患者后路手术并发症的防治 总被引:30,自引:0,他引:30
目的:分析下腰痛患者后路手术并发症出现的原因,探讨防治办法。方法:回顾分析我科自1988~1998年6月间采用后路手术治疗下腰痛,即腰椎间盘突出症和/或腰椎管狭窄症患者570例的临床资料。结果:33例发生术后并发症,发生率5.79%,早期(术后2周以内)并发症18例,晚期并发症15例,但无一例并发神经根损伤。结论:除了术中操作技能外,术前严格掌握手术适应证,术后及时观察、早期功能锻炼,都有利于并发症的防治。 相似文献
95.
Yasuhiro Yamaoka Takatomo Mine Hiroshi Tanaka Yoichiro Ishida Tosihiko Taguchi 《Knee surgery, sports traumatology, arthroscopy》2007,15(11):1346-1349
An avulsion fracture of the tibial tubercle is a common injury in traffic accident. If the fracture is closed, then a comparatively
good prognosis can be expected through reinforcement of the bone via osteosynthesis and the use of artificial ligaments. In
this case, an open wound was observed in the tibial tubercle, and the wound was so polluted that the healing process was significantly
delayed. It was therefore difficult to provide simultaneous surgical treatment and so three operations were required to perform
the reconstruction of the extensor mechanism. The reconstruction of extensor mechanism and the frame fixation between the
patella and tibia was performed. Six months after the injury, the patient was able to walk without aid, had a range of movement
from 5°to 130°, and did not show any indications of ADL disorder. Using this method of frame fixation between the patella
and tibia proved to be an effective technique for the reconstruction of the open knee extension mechanism injury. 相似文献
96.
Tadeusz F. Wisniewski 《European Journal of Trauma》2004,30(2):120-123
AbstractBackground: Posterior acromioclavicular dislocation is rare.
Dislocation associated with fracture of the clavicle and
simultaneous entrapment of the lateral end of the clavicle by
trapezius muscle has not been reported. Posterior dislocation
occurs frequently owing to forceful move of the scapula
anteriorly and superiorly or from direct force applied to the
lateral end of the clavicle and this may be associated with
clavicular fracture. In acute dislocations, open reduction,
internal joint stabilization and soft tissues reconstruction
have been recommended.Case Study: Acute posterior dislocation occurred in a 32-year-old man.
The lateral end of the clavicle was displaced posteriorly and
inferiorly, and firmly entrapped in trapezius muscle. The
clavicular fracture was undisplaced. The coracoclavicular
ligaments were stretched but intact. Open reduction was secured
with two smooth Kirschner wires. The disrupted soft tissues were
repaired. The clavicular fracture was not explored. Shoulder
movement started at 6 weeks. Wires were removed. 10 years later
he had pain-free, unrestricted shoulder movement, and the
radiographs showed wellreduced, essentially normal
acromioclavicular joint.Conclusion: Open reduction, internal joint stabilization and soft
tissue reconstruction will result in return and long lasting
unrestricted pain-free function of the shoulder. 相似文献
97.
98.
Two-level posterior lumbar interbody fusion for degenerative disc disease: improved clinical outcome with restoration of lumbar lordosis 总被引:2,自引:0,他引:2
Akira Hioki MD Kei Miyamoto MD PhD Hirotaka Kodama MD PhD Hideo Hosoe MD PhD Hirofumi Nishimoto MD Hirofumi Sakaeda MD PhD Katsuji Shimizu MD DMSc 《The spine journal》2005,5(6):600-607
BACKGROUND CONTEXT: Although posterior lumbar interbody fusion (PLIF) for degenerative lumbar diseases is routine, there are few reports on double-level PLIF. PURPOSE: To evaluate the clinical outcomes of double-level PLIF. STUDY DESIGN/SETTING: A retrospective study of operated cases in Gifu, Japan. PATIENT SAMPLE: Nineteen patients (8 men and 11 women, 59.5+/-10.2 years) who underwent double-level PLIF between 1996 and 2001. OUTCOME MEASURES: Operation time, blood loss, complications, the Japanese Orthopaedic Association (JOA) score for back pain and lumbar sagittal alignment were evaluated. METHODS: Patients were examined retrospectively at follow-ups of 3.6+/-1.7 years. Primary diseases were spondylolisthesis, spinal canal stenosis, degenerative scoliosis and herniated intervertebral disc. Fusion areas were L3 to L5 in 15 cases and L4 to S1 in 4 cases. RESULTS: The mean JOA score increased from an initial score of 12.9+/-3.5 to 21.3+/-4.9 at the final follow-up. There was a positive correlation (R=0.718, p<.001) between the increase in lordotic angle and the increase in the JOA score. Several parameters suggested that the surgical invasiveness was not minimal. CONCLUSION: Double-level PLIF provided satisfactory results and preserved lumbar spine lordosis. 相似文献
99.
JH-2000血液透析机研制 总被引:3,自引:0,他引:3
详细阐述国产JH-2000血液透析机的基本原理、组成和性能. 相似文献
100.