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71.
The objective of this study is to compare the effects of three different anesthetic combinations on the electroretinogram in the same animals under similar laboratory conditions. Thiopental–isoflurane (TI), medetomidine–ketamine (MK), and xylazine–ketamine (XK) were used on each of 12 healthy miniature schnauzer dogs (MS) with a period of at least 3 weeks in between subsequent anesthesia protocols, using the Dog Standard Protocol. The scotopic ERGs consisted of scotopic low stimulus strength (S) responses designated S1, S2, S3, S4, and S5, at 1, 5, 10, 15, and 20 min after dark adaptation, respectively, and scotopic standard stimulus strength (S-ST) responses. The photopic ERGs consisted of a photopic single flash (P) response and 31 Hz flicker (P-FL) responses. For S-ST (2.5 cd s/m2), the amplitude of the a-wave using TI was significantly lower than that using MK (adjusted P = 0.05) and XK (adjusted P = 0.03), and the implicit time of the a-wave was significantly shorter than that using MK (adjusted P = 0.04). For P (2.5 cd s/m2), the amplitude of the b-wave using XK was significantly higher than that using MK (adjusted P = 0.01). The implicit times of the b-wave using TI was significantly longer and shorter than that of MK for S1, S2 and P-FL and for S4 and S-ST, respectively, and than that of XK for S2 and P-FL and for S5 and S-ST, respectively. The results of the present study showed that TI affected both the amplitude and the implicit time of the a-wave for S-ST and the implicit time of the b-wave relatively more so than was the case when using XK or MK. Therefore, it appears that either XK or MK could be advantageous to use rather than TI for clinical studies.  相似文献   
72.
针对医学图像的模糊特点,结合模糊连接度,提出一种新的用模糊聚类分析检测圆弧的方法,它可以精确提取出圆弧.首先把曲线按一定长度进行分段处理,分别拟合出各段的圆心坐标和半径,通过模糊关系把具有一定相似性的聚为一类,把同一类中连续的段合在一起组成新段,再进行拟合,然后再对此段两端一定范围内寻找,直至找到最佳的圆弧.这种方法已应用到股骨头轮廓圆弧的提取.  相似文献   
73.
Abstract Background: Primary shoulder hemiarthroplasty is an established treatment modality for complex fractures of the proximal humerus. Long-term functional outcome is often disappointing. However, little is known about social implications particularly in the elderly. Methods: A single-institution case series of consecutive geriatric patients (age > 70 years) treated with shoulder hemiarthroplasty for complex fractures of the proximal humerus between 1994 and 1997 was analysed. Postoperative morbidity, long-term function, radiological outcome and social implications were evaluated. Results: Seventy-seven patients fulfilled the study criteria. Median age at the time of operation was 80 years (range 70–93 years). Systemic and local postoperative complications were observed in 8% including 2 patients (3%) with revision surgery. Postoperative mortality was 1%. Forty-eight patients (62%) were available for follow-up (median 49 months, range 25–80 months), 22 (29%) died from causes unrelated to hemiarthroplasty before follow-up and 7 patients (9%) did not attend follow-up examination. Median Constant-Murley score was 41 points (range 17–77 points). Long-term results concerning pain were satisfying. The Oxford shoulder score ranged from 14 to 40 (median 30). Forty-one patients (85%) still lived in their original environment and managed their daily life independently despite poor shoulder function. Four patients (8%) lived in a retirement home and 3 (6%) in a nursery home. Eighty percent of our patients were still able to use public transportation, do the daily shopping and wash their whole body by themselves. Conclusion: Most patients managed their daily life independently despite poor shoulder function.  相似文献   
74.
目的:较大样本观察晕可消胶囊治疗椎-基底动脉缺血性眩晕疗效及其对红细胞膜流动性的影响。方法:符合入选标准的门诊病例203例随机分为观察组(晕可消组)102例,对照组(维脑路通组)101例,治疗10d后行疗效评定并以荧光偏振法检测红细胞膜流动性的变化。结果:观察组疗效优于对照组,并显著改善了红细胞膜的流动性。结论:晕可消胶囊具有改善红细胞膜流动性作用,用于治疗椎-基底动脉缺血性眩晕疗效肯定,值得推广。  相似文献   
75.
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77.
陈莉 《护理学杂志》2007,22(10):47-48
对81例患者行乳房内聚丙烯酰胺水凝胶(PAHG)取出术。结果手术均获成功,手术时间1.5~5.5h,平均2.6h。术中出血量90~1080ml,平均645.0ml。住院时间7~15d,平均8.9d。无血肿、感染等并发症,MRI复查PAHG清除率均达95.0%。提出术前加强心理护理并完善术前准备,术中密切监测生命体征和出入量,及时补充血容量,保证手术野照明,充分灌洗手术腔隙,减少PAHG在体内残留等措施是保证手术成功的重要环节。  相似文献   
78.

Background  

The telomeric region of mouse chromosome 12 has previously shown frequent allelic loss in murine lymphoma. The Bcl11b gene has been identified and suggested as a candidate tumor suppressor gene within this region. In this study, we aimed to elucidate whether Bcl11b is mutated in lymphomas with allelic loss, and whether the mutations we detected conferred any effect on cell proliferation and apoptosis.  相似文献   
79.
80.
刺鼠信号蛋白对自体移植皮片中酪氨酸酶的活性影响   总被引:2,自引:0,他引:2  
目的 检测刺鼠信号蛋白对自体移植皮片中酪氨酸酶的活性影响,进一步认识自体移植皮片过度色素沉着的原因。方法 建立过度色素沉着的自体移植皮片的动物模型;利用免疫组织化学方法分别检测刺鼠信号蛋白作用前后自体移植皮片中酪氨酸酶的表达,并与对照治疗组及正常皮肤相比较。结果 酪氨酸酶的表达定位于表皮基底部黑色素细胞的胞浆,在大部分组织中呈阳性表达,经刺鼠信号蛋白作用后酪氨酸酶在自体移植皮片中的表达明显减少,与在其他各对照组中的表达差异有极显著意义(P<0.01)。结论 刺鼠信号蛋白在自体移植皮片中能竞争性拮抗α-MSH的黑色素合成,使皮片着色能力降低,从而证明皮片移植后表皮细胞中α-MSH的表达上调是皮片呈过度色素沉着的重要原因。  相似文献   
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