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941.
肿瘤合并颈动脉切除术的探讨   总被引:3,自引:2,他引:3  
肿瘤固着于颈动脉在临床实践中并非少见,如能将肿瘤与受累动脉一并切除,仍不无救治机会。通过体外或体内对患侧颈动脉压迫训练,促使大脑侧枝循环的建立,并采用脑血管造影或/和经颅多普勒血流检测仪(TCD)检测证实合格后,可将肿瘤及受累段颈动脉作整块切除。本文报告1987~1995年间,我们按上述方法给7位患者施行本术,取得较好的效果,无手术死亡及脑血管并发症。  相似文献   
942.
为了探讨正常及在噪声暴露过程中耳蜗毛细胞感受器电位非线性特性的变化规律,采用玻璃微电极在体毛细胞胞内记录的实验方法,记录了7只豚鼠(7耳)正常状态和白噪声暴露后耳蜗外毛细胞(OHC)胞内交流感受器电位输入-输出曲线(I-O曲线)。正常豚鼠耳蜗OHC交流感受器电位幅度在刺激声强度较低时呈线性增长,声强达到50~70dBSPL时幅度增长变慢,在80~100dBSPL时,幅度不再随刺激强度的增加而继续增加,出现饱和现象。测试耳在用100dBSPL时白噪声暴露10~20分钟后,感受器电位幅度普遍下降,I-O曲线的线性段延长,非线性段缩短,但高强度感受器电位幅度增大,出现“幅度重振现象”,与临床上观察的响度重振现象具有相似的特点。从而推测OHC感受器电位非线性特性减弱,发生幅度重振,可能是临床上主观响度重振现象的客观来源之一。  相似文献   
943.
用数字滤波及相关函数处理技术对10名(20耳)学龄前儿童短声诱发的TEOAE信号进行二次处理。结果表明:通过数字滤波及相关处理后的TEOAE信号比原始记录的TEOAE信号波形更加清晰,易于辨认,有效地提高了TEOAE信号的信噪比及识别率。  相似文献   
944.
寒冷损伤对新生犬循环血容量的影响   总被引:8,自引:0,他引:8  
为探讨寒冷损伤对新生儿发病机理,采用新生犬作为动物模型,用吲哚花菁绿颜料稀释法测定冷伤时的血容量。结果:血浆容量由正常的74±14ml/kg下降到低温时的49±9ml/kg。复温后,血浆容量继续下降至39±17ml/kg(P<0.01)。低温时存在不同程度的血压下降,代谢性酸中毒及颈动脉血流降低等循环障碍的表现。提示:对寒冷损伤新生儿应予扩容纠酸等综合治疗。  相似文献   
945.
946.
Transforming growth factor-α (TGF-α) is a potent mitogenic polypeptide. It is secreted by a variety of transformed cells and tumors, modifying tumor growth through autocrine or paracrine mechanism. In the present study, serum levels of TGF-α were determined by enzyme-linked immunosorbent assay (ELISA) in 27 normal females, 116 patients with benign ovarian tumors, and 42 patients with epithelial ovarian cancers (10 with stage I, 7 with stage II, 19 with stage III, and 6 with stage IV). The ELISA assay could detect a minimum level of serum TGF-α concentration at 10 pg/ml. Serum samples were obtained from normal females and from patients with benign or malignant ovarian tumors before initial surgery. The detectable rates were 11% (3/27) in normal females, 28% (32/116) in benign ovarian tumors, and 62% (26/42) in ovarian cancers. The detectable rates in serous and endometrioid ovarian cancers were 71 and 70%, respectively, which were higher than the rate of 33% in mucinous type. However, there was no obvious relationship between the detectability of serum TGF-α and the stages of ovarian cancers. The mean concentration of TGF-α in ovarian cancer was 159.8 pg/ml, which was significantly higher than 27.7 pg/ml in benign ovarian tumors (P< 0.001) as well as 15 pg/ml in normal females (P< 0.001). The mean concentrations of serum TGF-α in stages I to IV ovarian cancers were 133.5, 96.2, 194.8, and 178.3 pg/ml, respectively. The mean concentration of serum TGF-α in any two stages of ovarian cancers was not statistically different. In conclusion, measurement of serum TGF-α can be used as a supplementary tumor marker to differentiate a malignant ovarian tumor from a benign one. However, the concentration of serum TGF-α has no special relation with the stage of ovarian cancer itself. Because of the small number of stage I ovarian cancers with detectable TGF-α in the present investigation, it would probably not be feasible to differentiate a stage I ovarian cancer from a benign ovarian tumor based only on the level of TGF-α in serum.  相似文献   
947.
AIM—To investigate the immunogenicity and safety of existing recommendations for hepatitis B vaccination in preterm infants.METHODS—Recombinant hepatitis B vaccine (H-B-VAX II, 5 µg per dose) was given to 85 preterm infants divided into two groups, using two different schedules. Forty four group A infants with birthweights of < 2000 g received three doses at 1, 2, and 7 months of age. Forty one group B infants with birthweights of ?2000 g received three doses at 0, 1, and 6 months of age.RESULTS—After vaccination, 42 infants from group A (95%) and 37 infants from group B (90%) developed protective levels of antibody. The final seropositive rate and the geometric mean concentration of hepatitis B surface antibody between the two groups were not significantly different. The immune response of preterm infants to hepatitis B vaccines was similar to that of term infants in a previous study.CONCLUSIONS—Preterm infants can be given hepatitis B vaccines using one of the above two different schedules, at a cutoff birthweight of 2000 g.  相似文献   
948.
卵巢上皮性癌155例的治疗与预后   总被引:11,自引:0,他引:11  
目的:探讨卵巢上皮性癌的治疗与影响预后的因素。方法:对1970年1月至1992年12月在我院治疗的155例卵巢上皮性癌进行回顾性分析。全部手术切除标本经病理检查诊断并按FIGO分期标准进行分期,42例行2次手术,4例行3次手术。除6例外,余149例均于手术后行化疗,32例于第2次术后再次行化疗,9例因复发再次化疗。结果:2年、5年、10年的生存率分别为Ⅰ期92.4%、87.0%、70.6%;Ⅱ期91.9%、63.6%、47.8%;Ⅲ期59.9%、38.2%、19.2%;Ⅳ期25.0%、25.0%、0.0%(P<0.001)。6例未化疗者均在术后2年内死亡。结果表明,预后与临床分期、细胞分化、残留癌灶大小有关。5年生存率中,Ⅰ期为87.0%和Ⅲ期为38.2%(P<0.001);G1的5年生存率为95.9%,G3为11.8%(P<0.001);无残留癌灶者为97.6%,残留癌灶>2cm者为21.2%(P<0.001)。结论:在卵巢上皮性癌初次手术时残留癌灶<2cm,并于术后尽早开始化疗,可提高生存率。  相似文献   
949.
Purpose: Using different micropipettes for zona drilling and blastomere aspiration for embryo biopsy is prevalent at centers of preimplantation genetic diagnosis. The purpose of our study was to simplify the technique by using only one micropipette. Methods: In this animal model, ICR mouse embryos at the four-cell stage (n=446) were randomly allocated into two groups: a biopsied group (n=224) for blastomere aspiration and a control group (n=222) without micromanipulation. We used a drilling/biopsy micropipette to drill a hole in the zona by expulsion of acidified Tyrode’s solution and to aspirate the blastomere by gentle suction with the same micropipette and pull it out of the zona. One blastomere was biopsied from each embryo. Results: In all, 222 (99.1%) intact blastomeres were successfully biopsied from 224 embryos. Only two blastomeres were damaged during aspiration. The capacity for blastocyst development (92.4 vs 93.7%) was not different between the two groups, but the percentages of embryos hatching (51.8 vs 18.0%) and hatched (29.9 vs 8.1%) were significantly higher in the biopsied group than in the control group. Conclusions: This simplified technique of embryo biopsy is safe and highly efficient for obtaining blastomeres for preimplantation genetic diagnosis and may also facilitate hatching of the blastocysts.  相似文献   
950.
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