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101.
Between 1969 and 1995, 180 patients underwent complete resection of lung metastases during initial thoracotomy at our institute, involving the resection of 917 pulmonary nodules at 202 thoracotomy procedures. The overall postmetastasectomy 5- and 10-year survival rates were 46% and 30%, respectively. Of 111 patients who underwent segmentectomy and/or local excision, 57 had multiple metastases, 39 of whom were treated by Nd:YAG laser after 1986, and 18 by conventional procedures before 1985. The average number of tumors resected per patient treated with the Nd:YAG laser was significantly greater than that of those treated with conventional procedures. However, the survival curve of the laser-treated group was better than that of the laser-nontreated group. Moreover, slightly better survival was achieved in patients operated on after 1992 compared with those operated on before 1991. We conclude that the laser technique may be warranted to afford complete resection of metastases and adequate pulmonary reservation in combination with a selected approach for thoracotomy under the exact detection of tumor localization using the most recent high-quality computed tomography (CT) scan. Furthermore, a one-stage operation to control synchronous intra- and extrapulmonary malignamcies may become a possible option in combination with selective adjunctive therapy.  相似文献   
102.
本文报道准分子激光冠脉成形术(ELCA)8例,均为男性,年龄平均61岁。心梗4例(2例有梗塞后心绞痛),4例仅表现为心绞痛。冠脉造影显示LAD狭窄6支,LCX狭窄4支,RCA狭窄4支。按ACC/AHA分型B型5例,C型3例。均用ELCA+PTCA。根据血管直径选用1.3mm(能量密度14.5mJ)和1.6mm(能量密度21.0mJ)激光导管,频率20Hz。1例导引钢丝未能通过狭窄,ELCA失败,另1例二次心梗,经旁路移植后仍有心绞痛发作,心功能较差,其ELCA虽获成功,但因病情严重死亡。8例中ELCA成功7例,手术成功6例。  相似文献   
103.
The broad background of scattered light observed in spectra of cell suspensions is reduced by factors of up to 20 by immersion refractometry allowing for improved spectroscopic determination of the absorption properties of cells in the 325-820 nm range. Refractive-index matched spectra of E. coli C1a exhibit a set of resonant features near 422, 561, and 582 nm. Exposure wavelengths are chosen based on this spectrum and cell viability is investigated in E. coli suspensions exposed to 350, 400, 422, 440, and 700 nm radiation delivered in nanosecond pulses with total doses from 500 millijoules to 60 Joules. We observe a loss in cell viability for doses greater than 1 Joule at 422 nm and for all doses at other wavelengths; exposures of less than 1 Joule at 422 nm enhance growth. Excluding exposures at wavelengths within the resonant feature, longer wavelengths are less effective at reducing the viability of E. coli C1a. This indicates the occurrence of at least two absorption processes.  相似文献   
104.
All-Union Surgical Research Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Malinovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 12, pp. 653–657, December, 1991.  相似文献   
105.
目的总结冠心病患者行冠状动脉旁路移植术(CABG)和激光心肌血运重建术(TMLR)中的治疗难点、围术期处理要点,以提高冠心病患者的外科治疗效果。方法1997年5月~2006年1月,1405例冠心病患者中在体外循环下行CABG825例,其中单纯CABG666例,CABG+心瓣膜手术98例,CABG+室壁瘤手术55例,CABG+左心房粘液瘤摘除术2例,CABG+室间隔穿孔修补术2例,CABG+升主动脉成形术1例,CABG+纵隔内肿瘤切除术1例;非体外循环下CABG(OPCAB)500例;单纯TMLR30例,CABG+TMLR50例。结果每例移植旁路血管2.9±1.0支。住院死亡42例(3.0%),死亡原因包括出血、心肌梗死、低心排血量综合征、肾功能衰竭、多器官功能衰竭等。术后发生并发症70例,包括出血、低心排血量综合征、心肌梗死、肾功能不全等,均经积极的对症处理后治愈或好转。术前心绞痛(CCS)为~级的1177例患者中,术后1154例(98.0%)改善为0~级。术后随访857例(62.9%),随访时间8.3±2.9个月。随访6个月时788例(91.9%)无心绞痛发作,复查超声心动图提示:左心室射血分数0.66±0.10,较术前提高7.9%,生活质量较术前大为提高。结论CABG已成为治疗冠心病最有效的常规手术,只要能正确掌握适应证,有效地加强围术期管理,便可以扩大手术适应证范围,降低手术死亡率和并发症发生率,提高手术疗效。  相似文献   
106.
阐述了AGFALR5200激光相机的工作原理、日常使用保养。  相似文献   
107.
Objective  To assess the safety and efficacy of a modified fetoscopic laser ablation technique for the management of severe twin–twin transfusion syndrome (TTTS) in a large series of pregnancies.
Design  Prospective cohort study.
Setting  Tertiary referral fetal medicine unit.
Population  Women with pregnancies complicated by severe TTTS (Quintero stage III or IV), before 26 weeks of gestation.
Methods  Fetoscopic laser ablation of placental anastomoses was performed. The sonoendoscopic approach was used to identify the placental vascular equator and to photocoagulate crossing vessels.
Main outcome measures  Overall survival, fetal and perinatal mortalities, gestational age at delivery, birthweight, operating time and recurrence of TTTS.
Results  A total of 77 women underwent the procedure. The mean gestational age at treatment was 20 (range 16–26) weeks. On average, four vessels were ablated during each procedure, with a mean operative time of 15 (range 5–25) minutes. None of the women required a repeat fetoscopic laser treatment for recurrence of the TTTS. There was at least one survivor in 74% (57/77) of pregnancies, and the overall survival rate was 57% (88/154).
Conclusions  Fetoscopic laser ablation is a safe and effective form of treatment in the management of severe TTTS. The technique of identifying the common villous district of the placenta by ultrasound and photocoagulating any vessels crossing the vascular equator appears to be an acceptable alternative to both the nonselective and highly selective methods described so far. This approach is associated with a short operating time, low likelihood of TTTS recurrence or fetal anaemia and with survival results that are equivalent to previously reported techniques.  相似文献   
108.
This report describes a technique in which deep-seated CNS neoplasms, the volume and shape of which had been determined and stereotactically localized by computer reconstruction of CT data, were vaporized with a carbon dioxide laser attached to a stereotactic frame. The clinical results with 6 patients treated by this technique are presented.  相似文献   
109.
(1)目的 探讨鼻内窥镜下Nd:YAG激光治疗变应性鼻炎的方法。(2)方法 应用鼻内镜下Nd:YAG激光凝固中务甲前1/3端治疗变应性鼻炎126例。(3) 结果 随访1年,显效109例(86.5%),有效13例(10.3%),无效4例(3.2%),总有效率96.8%。(4)结论 鼻内镜下Nd:YAG激光凝固中鼻甲前1.3端治疗变应性鼻炎,具有视野清楚,操作简便,疗效好等优点,值得临床应用。  相似文献   
110.
目的:检测荷瘤鼠乳腺癌组织的双光子荧光光谱。方法:乳腺癌荷瘤鼠腹腔注射血卟啉(HpD)。以飞秒激光照射小鼠的癌组织部位及周围正常组织部位。观察HpD双光子荧光光谱。结果:小鼠的癌组织部位可观察到外源性HpD双光子荧光光谱,而正常组织部位未观察到明显的双光子荧光光谱。结论:结论:飞秒激光外源性血卟啉双光子荧光诊断可作为癌症诊断的新方法。  相似文献   
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