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101.
The SOS chromotest is a simple short-term genotoxicity assay measuring the induction of gene sfiA in Escherichia coli K-12. The recent availability of SOS tester strains with additional mutations in DNA repair or protection systems allows testing of DNA damaging compounds for genotoxic specificity. E. coli PQ300 differs from the standard SOS tester strain PQ37 in that it contains an additional mutation in gene oxyR that renders it more sensitive to oxidative genotoxins. The generation of reactive oxygen intermediates (ROI) by hydroperoxides (H2O2, t-butyl hydroperoxide, cumene hydroperoxide), gamma-radiation, glucose oxidase, and xanthine oxidase resulted in a more vigorous SOS response in strain PQ300 compared to strain PQ37. PQ300 was also more sensitive than PQ37 for the detection of reducing agents such as ascorbic acid, cysteine, and glutathione, which also alter the redox status of the bacterial cells. However, intercalating agents (adriamycin, bleomycin, and mitomycin C) and the UV- and radiomimetic compound 4-nitroquinoline-1-oxide whose DNA damaging potential are known also to involve ROI did not show significant differences between strains PQ37 and PQ300. It is concluded that the oxyR-deficient strain PQ300 is useful for detecting certain classes of genotoxins that change the oxidative/antioxidative balance of tester bacteria in the SOS chromotest.  相似文献   
102.
马显杰  夏炜  张辉  鲁开化  郭树忠  韩岩 《中国美容医学》2006,15(7):787-788,i0004
目的:探讨烧、创伤后,足背瘢痕挛缩所致仰趾畸形的治疗。方法:术中将足背瘢痕切除,彻底松解挛缩,将弓弦状伸肌腱切除部分或切断,切除部分挛缩的跖趾关节背侧关节囊,使关节复位,克氏针外固定,在拇指内侧或小趾侧,以跖趾关节处为蒂设计逆行皮瓣,转移覆盖外露的跖趾关节,供区及瘢痕切除后创面行全厚或断层皮片修复。结果:本组7例,均采用逆行皮瓣修复,畸形完全纠正,无继发畸形。结论:应用拇指及小趾侧方逆行皮瓣转移,治疗仰趾畸形可达到满意效果。  相似文献   
103.
104.
Introduction: Chronic groin pain is the most common long-term complication after open inguinal hernia repair. Traditional surgical management of the associated neuralgia consists of injection therapy followed by groin exploration, mesh removal, and nerve transection. The resultant hernia defect may be difficult to repair from an anterior approach. We evaluate the outcomes of a combined laparoscopic and open approach for the treatment of chronic groin pain following open inguinal herniorrhaphy. Methods: All patients who underwent groin exploration for chronic neuralgia after a prior open inguinal hernia repair were prospectively analyzed. Patient demographics, type of prior hernia repair, and prior nonoperative therapies were recorded. The operation consisted of a standard three trocar laparoscopic transabdominal preperitoneal hernia repair, followed by groin exploration, mesh removal, and nerve transection. Outcome measures included recurrent groin pain, numbness, hernia recurrence, and complications. Results: Twelve patients (11 male and 1 female) with a mean age of 41 years (range 29–51) underwent combined laparoscopic and open treatment for chronic groin pain. Ten patients complained of unilateral neuralgia, one patient had bilateral complaints, and one patient complained of orchalgia. All patients failed at least two attempted percutaneous nerve blocks. Prior repairs included Lichtenstein (n=9), McVay (n=1), plug and patch (n=1), and Shouldice (n=1). There were no intraoperative complications or wound infections. With a minimum of 6 weeks follow up, all patients were significantly improved. One patient complained of intermittent minor discomfort that required no further therapy. Two patients had persistent numbness in the ilioinguinal nerve distribution but remained satisfied with the procedure. Conclusions: A combined laparoscopic and open approach for postherniorrhaphy groin pain results in good to excellent patient satisfaction with no perioperative morbidity. It may be the preferred technique for the definitive management of chronic neuralgia after prior open hernia repair.  相似文献   
105.
跨矢状窦脑膜瘤术中矢状窦的处理   总被引:1,自引:1,他引:0  
目的总结跨矢状窦脑膜瘤术中矢状窦的处理方法.方法对26例跨矢状窦脑膜瘤及受累矢状窦进行切除,依具体情况重建或不重建矢状窦.结果该组病人无手术死亡,手术后均未加重原有神经功能障碍,无脑血液回流障碍,7例重建矢状窦者未发现有矢状窦内血栓形成.结论矢状窦旁脑膜瘤的治疗除肿瘤切除外,对受累上矢状窦处理是否彻底对预防术后复发是至关重要的.对受累矢状窦应按具体情况按一定的原则进行积极处理.  相似文献   
106.
Summary The aim was to develop a model for study of nerve regeneration in nerve roots above the level of the dorsal root ganglion and to investigate the use of freeze-thawed muscle autografts for repair of nerve roots at this level.Four adult sheep were used for the experiment. A laminectomy was performed at the lumbosacral junction and the S2 root identified. Both the dorsal and ventral S2 roots were divided unilaterally within the dura and a freeze-thawed muscle graft was inserted into the nerve gap.When assessed at 6 months an action potential was recordable from the ventral root in one sheep. Histological examination of the nerve roots showed evidence of regeneration across the graft in the ventral roots of all the sheep and the dorsal roots of some.This preliminary work indicates a capacity for regeneration of the cauda equina and that freeze-thawed muscle can support this. It provides a useful model for further study of nerve root repair.  相似文献   
107.
肩肱皮瓣修复颈部瘢痕挛缩畸形疗效分析   总被引:1,自引:0,他引:1  
目的:探讨颈部瘢痕挛缩畸形的有效外科治疗手段。方法:采用瘢痕广泛松解、双侧或单侧肩肱皮瓣转移,同时用全厚皮片移植修复供瓣区创面。结果:本组21例中,17例手术一次性完成,4例分两次完成。不但改善了患者的上肢功能,还可进一步改善患者颈部的活动度。结论:瘢痕广泛松解、双侧或单侧肩肱皮瓣转移,同时用全厚皮片移植修复供瓣区创面是颈部瘢痕挛缩畸形的有效外科治疗手段。  相似文献   
108.
BACKGROUND AND OBJECTIVES: Inguinal hernia repair is one of the most frequently performed pediatric surgical operations. Several pediatric laparoscopic inguinal hernia repair techniques have been introduced. But debate is unresolved regarding the feasibility of laparoscopy for treating pediatric inguinal hernias. METHODS: A retrospective cohort study enrolled 33 patients who underwent congenital inguinal hernia repair by either the new laparoscopic flip-flap technique or conventional open repair. Patients were divided into 2 groups according to the type of surgery: Group A included those who underwent the new laparoscopic technique, and Group B included those who underwent conventional open repair. RESULTS: Group A comprised 15 patients (mean age, 39 months), and group B comprised 18 (mean age, 44 months). Mean operative time was 47.5 minutes for Group A versus 27.5 minutes for Group B. Intraoperative complications for Group A included 1 case (7%) of vas deferens injury, and 3 cases (20%) in which the flaps were torn during suturing. In Group B, no intraoperative complications were encountered. In both groups, the mean postoperative hospital stay was 5.5 hours. Postoperative follow-up of 3 months revealed recurrence in 4 patients in Group A (27%), while there were no recurrences in Group B. CONCLUSION: Our preliminary experience shows unsatisfactory outcomes with laparoscopic flip-flap hernia repair in children. In spite of advancement in the application of laparoscopy in pediatric surgery, conventional open hernia repair is still the gold standard for children, in our experience. Future studies with more numbers and longterm follow-up should be conducted.  相似文献   
109.
Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the development of AD.  相似文献   
110.
目的 探讨吻合血管的胸脐皮瓣移植修复足踝部大面积软组织缺损的临床效果.方法 对18例足踝部大面积软组织缺损(其中11例伴胫前或胫后血管节段损害)采用胸脐皮瓣游离移植修复创面.创面面积12cm×6cm~32cm×12cm.结果 移植皮瓣全部成活,3例足跟部缺损的病人术后因长期磨擦形成足跟部慢性溃疡;3例皮瓣臃肿,需再次手术整形.其余病例外观和足踝部功能恢复满意.结论 胸脐皮瓣为腹壁下动脉供血,血运丰富,血管解剖恒定,血管蒂长,可切取面积大且易于切取,适宜修复足踝部软组织缺损,尤其适用于缺损面积大、胫前或胫后血管之一长节段损害者.  相似文献   
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