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991.
992.
OBJECTIVE: Avoidance of potential iatrogenic nerve injury during insertion of Ilizarov fine wires into areas of high anatomic risk by using a modified nerve stimulation technique. INDICATIONS: Application of the Ilizarov ring fixator to areas of high anatomic hazard, in situations where anatomic topography may be distorted by previous surgery, trauma, or congenital anomalies. CONTRAINDICATIONS: Use of systemic muscle relaxants. Caution in patient with cardiac pacemaker. SURGICAL TECHNIQUE: Preliminary experiments showed that a standard nerve-stimulating device can deliver a negatively charged, monophasic square pulse of current through Ilizarov wires. During the application of an Ilizarov frame to potentially hazardous anatomic regions, providing no systemic muscle relaxants are used, a voltage field sufficient to cause nerves in close proximity to the Ilizarov wire to depolarize is produced. Identification of a distal muscle twitch provoked by the stimulation may indicate a potential for iatrogenic nerve injury. RESULTS: Results show that with the nerve stimulator set at 2.5 mA (pulsed at a frequency of 2 Hz), peripheral nerves are stimulated if they lie within 5 mm of the wires. Should a distal muscle twitch occur, wires should be repositioned so that equivalent stimulation produces no twitch. The technique was used during Ilizarov frame application in ten patients, with only a single occurrence of distal muscle twitches in a lower-leg frame. Following repositioning of the Ilizarov wire in this case, no further twitches were observed, indicating that no Ilizarov wire was inserted close to peripheral nerves. No neurologic impairment was present postoperatively.  相似文献   
993.
Malignancy has long been described as a risk factor for venous thrombembolism (VTE) with its associated complications such as pulmonary embolism. Several reports have described possible associations and explanations at a molecular level to this thrombophilic phenomenon. In addition, therapy for a malignancy may also pose an additional risk factor for VTE. In this report, we review the pathophysiology and clinical relevance of gynecological malignancies, their multimodal treatment, and VTE. A critical discussion of current national and international guidelines to prophylaxis and treatment is presented.  相似文献   
994.
目的:探讨急诊外伤性胃肠穿孔的CT征象及诊断价值。方法:收集18例经手术证实的外伤性胃肠道穿孔的临床资料及CT征象,分析与总结胃肠道破裂穿孔CT扫描的各种有价值的表现。结果:18例外伤急诊患者中,胃、十二指肠、空回肠与结肠穿孔各1,2,12,3例,其中空回肠为多处破裂,CT主要征象为腹腔散在积液征、游离气腹征、肠系膜与肠壁增厚模糊征、造影剂外溢征。结论:CT扫描在外伤性胃肠道穿孔急诊患者的检查中有定性诊断价值,综合分析各种征象,会明显提高CT的诊断正确率。  相似文献   
995.
It's all about sex: gender, lung development and lung disease.   总被引:1,自引:0,他引:1  
Accumulating evidence suggests that gender affects the incidence, susceptibility and severity of several lung diseases. Gender also influences lung development and physiology. Data from both human and animal studies indicate that sex hormones might contribute to disease pathogenesis or serve as protective factors, depending on the disease involved. In this review, the influence of gender and sex hormones on lung development and pathology will be discussed, with specific emphasis on pulmonary fibrosis, asthma and cancer.  相似文献   
996.
OBJECTIVE: Prospectively to compare lymphatic drainage after ultrasonic dissection, an electrocoagulation technique and sharp dissection in the groin during surgery for recurrent sapheno-femoral incompetence. DESIGN: Prospective, randomised study comparing three surgical techniques. METHODS: Thirty-six consecutive patients undergoing surgery for recurrent sapheno-femoral incompetence were randomised. Twelve patients underwent dissection with ultrasound, 12 with electrocoagulation and 12 controls had sharp dissection with ligation of scar and lymphatic tissue using absorbable suture material. RESULTS: The mean drain output per patient was 13.5 ml in the ultrasonic group, 15.4 ml in the electrocoagulation group and 8.3 ml in the suture ligation group. Six minor cases of lymphatic leakage occurred in the ultrasonic group. This resulted in no clinical problem. There were no other significant differences between the three groups. CONCLUSIONS: There is no detectable advantage for the use of ultrasound or electrocoagulation in recurrent saphenous high ligation compared to sharp dissection.  相似文献   
997.
Results of total and subtotal colon resections in children.   总被引:2,自引:0,他引:2  
AIM: The treatment of long-segment neuronal intestinal malformations confronts the paediatric surgeon with the problems of diagnosis, suitable surgical methods and postoperative care. The evidence based only on ganglion cells is inadequate to decide about the required extent of resection and does not exclude hypoganglionosis and disseminated dysganglionosis. For the surgical treatment, pouch procedures as well as the usual resection techniques according to Rehbein, Soave, and Duhamel are discussed. Since studies with greater numbers of patients are rare, we present here our own results. METHODS: 48 patients with long segment intestinal malformations were treated in our hospital between 1990 and 2000. A total of 35 patients were examined 1.5-6 years after definitive surgical therapy. Rehbein's anterior resection was performed in all cases. RESULTS: Our findings showed that the surgical treatment with Rehbein's technique offers good results, both with respect to complications as well as to the postoperative course, although a 4 cm long aganglionic segment remains in situ. We found that results were better after ascendorectostomy (n = 22) compared to ileorectostomy (n = 11). Earlier publications of this group (13) show that the histology of the proximal resection margin is decisive for the prognosis. Hypo- and aganglionic segments should be completely resected while short IND segments of the colon or terminal ileum may remain in situ. However, the additional effect of the aganglionic segment of the distal rectum and the decreased peristaltic flow of the pre-anastomotic bowel has to be taken into account. Further investigations are required to find out whether a combination of Soave's endorectal pull-through with a remaining neuronal dysplastic segment proximal to the resection margin may give better results or if the frequency of postoperative enterocolitis and incontinence increased in cases of long segment intestinal neuronal malformations. Accurate diagnosis of myenteric plexus is decisive for an optimal treatment and therefore, considering our results, it is essential that in case of newborns getting to hospital with colon obstruction and suspicion of neuronal intestinal malformation full thickness biopsies from the distal and proximal colon may be taken simultaneously with the enterostomy. Generally ileostomy is performed in patients suspected of long-segment neuronal intestinal malformations. Mucosa suction biopsies from the distal and proximal stoma side are less informative compared to full thickness biopsies.  相似文献   
998.
999.
1000.
Using fura-2 loaded neural tumour cells, SK-N-SH, we demonstrate that receptor-mediated activation of phosphoinositide hydrolysis not only causes the release of Ca2+ from intracellular stores but also causes a concomitant influx of extracellular Ca2+. Thapsigargin (TG), a sesquiterpene lactone, causes a sustained elevation of intracellular Ca2+ and depletion of the inositol 1, 4, 5-trisphosphate-sensitive intracellular Ca2+ stores. In the absence of extracellular Ca2+, the increase in intracellular Ca2+ concentration ([Ca2+]i) was transient, suggesting that thapsigargin activates both intracellular mobilization and the influx of Ca2+ from extracellular space. These results are consistent with the proposal that the depletion of the inositol 1, 4, 5-trisphosphate-sensitive intracellular Ca2+ pool serves as a signal for Ca2+ influx.  相似文献   
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