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101.
瞬间反应式二次谐波显像评价正常犬肝脏超声学造影的实验研究 总被引:2,自引:1,他引:1
目的:评价瞬间反应二次谐波显像(Transient response second harmonec imaging,TRSHI)对正常肝脏声学造影的增强效果及动态变化规律,并与常规连续二次谐波显像进行对比分析。方法:6只健康杂种犬 经外周静脉注射氟碳声学造影剂,分别用常规二次谐波显像和瞬间反应式二次谐波显像扫描肝脏。造影效果评价使用视觉评分和视频密度分析。结果:常规二次谐波显像有4次I级增强、4 相似文献
102.
103.
目的 总结可吸收内固定材料自身增强聚丙交脂(SR-PLLA)的临床应用体会。方法 采用波兰进口SR-PLLA螺钉、棒、线治疗四肢松质骨骨折22例,随访摄片观察骨折愈合情况,检查关节活动功能。结果 术后有两侧出现并发症,一例局部少量积液,经2次穿刺抽液加压包扎痊愈;一例患者过早去除石膏功能锻炼,螺钉松动滑出,经手术复位石膏外固定治愈,无感染或过敏等情况发生。结论 掌握可吸收材料的生物力学特点,并选择适当的病例,可以最大限度地发挥可吸收内固定材料的优势。 相似文献
104.
We have previously isolated a drug-resistant, [PC3(R)], variant of human prostate PC3 cell line, which showed significant resistance (>10-fold) to adriamycin. No known mechanisms of drug resistance were found; however, resistant cells expressed more bcl2, c-myc, and ms oncogenes compared to the sensitive cells. In this study, we found that buthionine sulfoximine (BSO), an inhibitor of gamma-glutamyl-cysteine synthetase, decreased glutathione levels by 80-90% in both cell lines. BSO treatment down-modulated Ras protein only in PC3(R) cells and caused a 4-fold sensitization of PC3(R) cells to adriamycin without affecting PC3(W) cells. Farnesol treatment also inhibited expression of Ras protein and concomitantly reversed adriamycin resistance in PC3(R) cells, indicating that altered levels of ras expression plays an important role in drug resistance in PC3(R) cells. 相似文献
105.
A 23-year-old male involved in a high-speed collision acquired, among other injuries, a wide fracture distraction at C2/C3. Reduction was delayed by an enlarging vertebral artery pseudo-aneurysm at the site of injury which was successfully treated by proximal endovascular occlusion with a detachable polymer-filled balloon. A traumatic arachnoid cyst or pseudomeningocele was also demonstrated at the injury site but intervention was not required. The treatment and outcome of these three uncommon injuries in the literature is reviewed and discussed. Given the severity of the injury, the absence of severe long-term neurological disability is notable. 相似文献
106.
107.
Our previous studies have demonstrated that supraspinal GABAergic receptors are differentially involved in the antinociception induced by morphine and beta-endorphin given intracerebroventricularly (i.c.v.) in the tail-flick and hot-plate tests. These two models employed a phasic, thermal nociceptive stimulus. The present study was designed to examine the possible involvement of supraspinal GABAergic receptors in opioid-induced antinociception in the formalin test. Morphine (1 microg) and beta-endorphin (1 microg) given i.c.v. displayed the almost complete inhibitory effects against the hyperalgesic response in both phases. Muscimol (75-100 ng) and baclofen (5-10 ng) injected i.c.v. produced the hypoalgesic response in the both phases. The hypoalgesic response induced by muscimol and baclofen observed during the second phase was more pronounced than that observed during the second phase. Baclofen (2.5 ng), at the dose which did not affect the hyperalgesic response, resulted in a significant reversal of the i.c.v. administered beta-endorphin-induced hypoalgesic response observed during the second, but not the first, phase. However, the hypoalgesic response induced by i.c.v. administered morphine was not changed by the same dose of muscimol or baclofen injected i.c.v. Our results indicate that, at the supraspinal level, GABA(B)receptors appear to be involved in the modulation of antinociception induced by supraspinally administered beta-endorphin, but not morphine, in the formalin test model. 相似文献
108.
Chiu HJ Tsai SJ Chen JY Lin CY Bai YM Song HL Lai HC Hong CJ 《Psychiatry research》1999,87(2-3):245-248
We investigated the association between schizophrenic psychosis and an intronic polymorphism of the presenilin-1 (PS1) gene in a Chinese population. Schizophrenic and control groups had similar PS1 genotype distributions and allele frequencies, indicating that this polymorphism may not be involved in the development of schizophrenia. 相似文献
109.
110.
Goodman SB Song Y Chun L Regula D Aspenberg P 《The Journal of bone and joint surgery. British volume》1999,81(6):1069-1075
We implanted bone harvest chambers (BHCs) bilaterally in ten mature male New Zealand white rabbits. Polyethylene particles (0.3+/-0.1 microm in diameter, 6.4 x 10(12) particles/ml) were implanted for two, four or six weeks bilaterally in the BHCs, with subsequent removal of the ingrown tissue after each treatment. In addition to the particles, one side also received 1.5 microg of recombinant transforming growth factor beta1 (TGFbeta1). At two weeks, the bone area as a percentage of total area was less in chambers containing TGFbeta compared with those with particles alone (7.8+/-1.3% v 16.9+/-2.7% respectively; 95% confidence interval (CI) for difference -14.0 to -4.30; p = 0.002). At four weeks, the percentage area of bone was greater in chambers containing TGFbeta compared with those with particles alone (31.2+/-3.4% v 22.5+/-2.0% respectively; 95% CI for difference 1.0 to 16.4; p = 0.03). There were no statistical differences at six weeks, despite a higher mean value with TGFbeta treatment (38.2+/-3.9% v 28.8 +/-3.5%; 95% CI for difference -4.6 to 23.3; p = 0.16). The number of vitronectin-receptor-positive cells (osteoclast-like cells) was greater in the treatment group with TGFbeta compared with that with particles alone; most of these positive cells were located in the interstitium, rather than adjacent to bone. TGFbeta1 is a pleotropic growth factor which can modulate cellular events in the musculoskeletal system in a time- and concentration-dependent manner. Our data suggest that there is an early window at between two and six weeks, in which TGFbeta may favourably affect bone ingrowth in the BHC model. Exogenous growth factors such as TGFbeta may be a useful adjunct in obtaining osseointegration and bone ingrowth, especially in revisions when there is compromised bone stock and residual particulate debris. 相似文献