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991.
就米非司酮配伍采米前列醇序贯用药终止7周内早孕118例进行临床观察,发现完全流产率92.37%,不全流产率5.93%,持续妊娠率1.69%。临床证明该方法方便、安全有效、副作用极小,但个别孕妇产生不全流产,引起出血过多及出血时间延长。不全流产率有随孕妇年龄、孕龄、孕次增加而增加的趋势。 相似文献
992.
Urs Brägger Urs Häfeli Beat Huber Christoph H. F. Hämmerle Niklaus P. Lang 《Clinical oral implants research》1998,9(4):218-224
In most of the studies on long-term radiographic evaluations of crestal bone levels adjacent to dental implants, no baseline radiographs taken immediately post-surgically had been obtained.The aim of this study was to test the reproducibility of a simple radiographic method for linear measurements of changes in bone levels and to evaluate changes in crestal bone levels adjacent co non-submerged ITI® implants 1 year following the surgical procedure. From 128 patients enrolled in a clinical and radiographic longitudinal study 40 patients also had radiographs taken immediately postsurgically. They were, however, not obtained as “identical” images. The radiographs were mounted onto slides and projected on a screen. Mesially and distally from 57 implants triplicate linear measurements of the distance implant shoulder to bone crest were taken, using known dimensions of the implants as internal reference distances. The median difference of 213 (out of 228 possible) duplicate measurements was 0.00 mm (ranging from ?1.72 mm to +1.47 mm when comparing the second co the third reading). Some 81% of the double measurements were within ±0.5 mm and the precision was 0.30 mm. In the immediate postoperative radiographs the median mesial bone level was located at 2.07 mm (distally 2.19 mm) from the implant shoulder. A statistically significant amount of bone loss in the first year was observed mesially (median=?0.78 mm) and distally (0.85 mm)(Wilcoxon matched pairs signed rank test ±0.001). No statistically significant influence of the implant location, the implant length, type of the implant (screw; cylinder) was observed (Kruskal-Wallis P>0.05).The age of the patients was not correlated significantly to the amount of bone loss observed. In conclusion, methodological limitations existed when evaluating linear bone changes in non-identical radiographs using reference dimensions of the implants. The amount of postsurgical bone loss estimated in other studies was confirmed when using an immediate postoperative radiograph as a baseline. 相似文献
993.
用高速离心、分段盐析、亲和层析、超滤和阴离子交换层析法,从牛胎盘中分离纯化出一种肝细胞生长因子。结果表明,此因子的最终得率为0.005mg/g牛胎盘,其分子量约为99000u,它能强烈刺激原代培养大鼠肝细胞的DNA合成。提示利用自制的亲和层析凝胶,通过此提纯流程可以得到一种肝细胞生长因子。 相似文献
994.
作者通过对1例冲动症案例的分析,结合文献报道,初步阐述了冲动症的概念范围、临床特征与诊断标准。并讨论了其与强迫症、性心理障碍、正常性犯罪之间的区别和责任能力的评定。 相似文献
995.
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997.
采用酶动力学及聚丙烯酰胺凝胶电泳方法研究了NaHSO3、NaN3、KSCN、DDC对酪氨酸酶的抑制作用。NaHSO3、NaN3、KSCN为非竞争性抑制作用,随着抑制剂浓度增加,酶活性逐渐减弱。当NaHSO3、NaN3、KSCN的浓度分别达到1.2mmol/L12。5mmol/L12.5mmol/L时,酶活性的抑制率为100%、50%、24%。DDC对酪氨酸酶的抑制作用为竞争性抑制作用,其浓度达4mmol/L时,酶活性100%受到抑制。 相似文献
998.
A. C. W. Chan S. C. S. Chung A. P. C. Yim J. Y. W. Lau E. K. W. Ng A. K. C. Li 《Surgical endoscopy》1997,11(5):438-440
Background: The lack of depth perception and spatial orientation in video vision are the drawbacks of laparoscopic surgery. The advent of a three-dimensional camera system enables surgeons to regain binocular vision and may be advantageous in complex laparoscopic procedures. Methods: We prospectively studied two groups of surgeons (with and without experiences in laparoscopic surgery) who performed a designated standardized laparoscopic task using a two-dimensional camera system (Olympus OTV-S4) vs a three-dimensional camera system (Baxter-V. Mueller VS7700) and compared their time performances. Results: The results suggested that only experience in laparoscopic surgery had significant effect on individual's performance. We could not demonstrate any superiority of the 3D system over the 2D system. However, two-thirds of the surgeons commented that the depth perception did improve. Conclusions: With further refinement of the technology, the 3D system may improve its potential in laparoscopic surgery. 相似文献
999.
OBJECTIVES: This study examined the morbidity and mortality from bicycling injuries in Wuhan, China. METHODS: Police department data for the year 1993 complemented by data from emergency room interviews were analyzed. RESULTS: The death rate from bicycling injuries was estimated as 2.2 per 100000 population, more than seven times the rate for the United States. At least 79% of the fatalities and 17% of the emergency room cases sustained head injuries, the majority (71%) of which resulted from contact of the head with the concrete or asphalt road. None of the patients was wearing a helmet at the time of injury, and helmet use among the general bicyclist population was nonexistent. CONCLUSIONS: Bicycle-related head injury is an important public health issue in China. The effectiveness of safety helmets in developing countries needs to be evaluated. 相似文献
1000.
为了探索单疱病毒性角膜炎的发病机制和快速诊断HSK。方法应用多聚酶链反应对感染的HSK的20只纯新西兰白兔和60例HSK患者的角膜进行了单疱病毒-1-DNA检测。结果急性感染期的5只兔角膜和12只人角膜均阳性;用稳定期45d的兔角供体行部分穿透性角膜移植术,术后50d10只兔角膜中7只阳性,稳定期6个月-6年的18只人角膜片,12只阳性;30例临床可疑HSK角膜刮取物,26例阳性;5只未感染HSK 相似文献