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81.
40例电视胸腔镜手术体会 总被引:2,自引:0,他引:2
目的 探讨电视胸腔镜(VATS)手术的优点、适应证和手术技巧。方法 回顾总结VATS手术40例。病种有原发性自发性气胸20例,多发性肺大疱3例,Ⅰ期肺癌3例等。手术方式有肺大疱切除23例,肺叶切除术3例(辅助小切口),肺楔形切除4例,纵隔肿瘤切除术3例,结核瘤切除1例,活检3例,胸膜粘连术3例,射频消融1例,纤维板剥脱术1例。结果 本组病例手术时间平均65分钟,失血量少于100ml,中转开胸2例,术后胸液总量平均150ml。胸管置留时间1~7天,平均住院时间7.8天,无气胸、良性肿瘤和结核复发,恶性胸水明显减少或消失,无持续漏气、二次开胸止血和手术死亡等并发症。结论 VATS手术适应证范围较广,微创出血少,美观,恢复快,只要掌握了手术技巧,操作便捷,并发症少,疗效满意。 相似文献
82.
目的 观察自体角膜缘上皮移植联合贝复舒对角膜缘上皮修复的作用。方法 随机选择翼状胬肉患者98例(98只眼),治疗组为自体角膜缘上皮移植联合贝复舒,对照组为翼状胬肉切除联合贝复舒。术后每日观察角膜上皮缺损区的修复情况,并随诊观察复发情况。结果 治疗组角膜缘上皮平均修复时间为3.1天,对照组4.2天,有显著差异性。随诊6个月发现对照组有一例复发,均未发现感染。结论 自体角膜缘上皮移植联合贝复舒可使角膜缘上皮修复时间快于翼状胬肉切除联合贝复舒。复发率均较低,表明自体角膜缘上皮移植联合贝复舒治疗翼状胬肉可以加快角膜缘上皮修复,减少复发及感染的机会。 相似文献
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A method has been derived for calculating the mean absorption time of an oral drug and its interconversion metabolite which is generated from the drug systemically and presystemically. The method evolves from the convolution integral and requires plasma AUC and AUMC values after separate intravenous administration of the drug and its interconversion metabolite and oral administration of the drug. It can also be used to calculate the mean input time of a drug undergoing reversible metabolism and administered by any other extravascular route. Results of a simulation study using both errorless and errant data indicate that, when the absorption rate constant of a drug or its interconversion metabolite is not much larger than the apparent elimination rate constant, the proposed method performs satisfactorily. However, when the absorption rate constant of a drug or its interconversion metabolite is much larger than the apparent elimination rate constant, the proposed method appears to be inaccurate. 相似文献
86.
Little is known about whether patients with photosensitive disorders exhibit a different ultraviolet erythema time course from subjects with a normal response to sunlight. We have described the application of an instrument for ambulatory monitoring of the development of ultraviolet erythema by a reflectance method in a group of patients with chronic actinic dermatitis (CAD) and in a group of normal subjects. Investigations of the time course have been reported previously but the techniques used relied upon manual measurement. Consequently sampling frequencies have been considerably lower than the one-minute sample rate used here. We have not demonstrated any difference in the rate at which erythema develops and peaks between patients with CAD and subjects with a normal response to sunlight. 相似文献
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把分段线性函数和斜波脉冲函数进行统一处理,定义成新的函数,使得新的函数既保持了原先两种函数的基本特性,又获得微分和积分递推算法。应用中具有方便,快速计算的优点。 相似文献
89.
T.G. van Kooten J.M. Schakenraad H.C. van der Mei A. Dekker C.J. Kirkpatrick H.J. Busscher 《Medical engineering & physics》1994,16(6):506-512
In this study, human umbilical vein and human saphenous vein endothelial cells were seeded on glass and exposed to fluid shear in a parallel-plate flow chamber. Cell retention, morphology and migration were studied as a function of shear stress and of adhesion time prior to exposure to shear. Three-hour and 24-h adhesion times gave rise to comparable cell retention values after 2 h of flow for both cell types. Cell retention decreased from 85 to 20% as shear stress increased from 88 to 264 dynes cm−2 (8.8 to 26 Pa). Mean spreading areas decreased after the onset of flow, but subsequently stabilized to plateau values, which were smaller at higher shear stresses. Shape factors increased faster to higher values as cells were exposed to higher shear stresses, without any obvious preference in orientation of the cells with respect to the direction of flow. Migration was unidirectional with flow and linear with time. Migration was faster for cells which had adhered for 24 h than for cells which had adhered for 3 h and was accompanied by the presence of fibrillar structures left behind on the surface upstream of migrating cells. It is concluded that after 3 h adhesion to glass, cells have adhered with an adhesion strength that does not substantially increase during the next 21 h. However, during this time changes in cell-substratum interactions seem to occur judging by the differences in, e.g., migration rates. 相似文献
90.
用机械分离法从豚鼠前庭感觉上皮中分离出不同种类的前庭感觉毛细胞(VHC)。VHC主要可分为Ⅰ型和Ⅱ型细胞。两种细胞形态虽有所差异,但一般均有四形或瓶形胞体,胞核位于细胞基部,胞颈和纤毛变化较大。细胞的活性可通过1%中性红染色鉴定,发现在室温下,1h内大约90%以上的分离VHC可维持其正常形态和活性。并参照对外毛细胞形态的研究提出活性VHC的鉴别标准。此项工作为进一步研究VHC的感觉机制和某些疾病的发生机理打下了基础。 相似文献