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81.
Nasopharyngeal carcinoma (NPC) is a head and neck cancer rare throughout most of the world but common in certain geographic areas, such as southern Asia. While environmental factors and genetic susceptibility play important roles in NPC pathogenesis, the Epstein-Barr virus in particular has been implicated in the molecular abnormalities leading to NPC. There is upregulation of cellular proliferation pathways such as the Akt pathway, mitogen-activated protein kinases, and the Wnt pathway. Cell adhesion is compromised due to abnormal E-cadherin and beta-catenin function. Aberrations in cell cycle are due to dysregulation of factors such as p16, cyclin D1, and cyclin E. Anti-apoptotic mechanisms are also upregulated. There are multiple abnormalities unique to NPC that are potential targets for novel treatments. 相似文献
82.
83.
The authors have shown that exogenous nitric oxide (NO) protects innervated skeletal muscle against reperfusion injury. This study further evaluated the effects of exogenous NO donor on denervated skeletal muscle. Forty-eight denervated rat cremaster muscles underwent 3 hr of ischemia, followed by 90 min of reperfusion, and received systemic infusion of 100 nmol/min s-nitroso-n-acetylcysteine (SNAC) or an equal amount of phosphate-buffered saline (PBS). Results showed that the average diameter in 10 to 20 microm arterioles was between 107 percent and 123 percent of baseline in the SNAC group, and between 55 percent and 84 percent in the PBS group during 90 min of reperfusion. These values in 21 to 40 microm and 41 to 70 microm arteries were between 100 percent and 110 percent in the SNAC group, and between 70 percent and 90 percent in the PBS group from 20 to 90 min of reperfusion. Compared to the PBS group, the SNAC group had a statistically significantly greater vessel diameter in both 10 to 20 microm (p<0.001) and 21 to 40 microm arterioles (p<0.01) during 90 min of reperfusion, and in 41 to 70 microm arteries (p<0.02) from 20 to 90 min of reperfusion. The overall blood flow of the muscle in the SNAC group increased from 37 percent of baseline at 10 min to 108 percent at 40 min of reperfusion, and remained above baseline thereafter. In contrast, this value in the PBS group was only between 27 percent and 68 percent of baseline during 90 min of reperfusion. The blood flow was statistically significantly (p<0.03) greater in the SNAC group than in the PBS group from 40 to 90 min of reperfusion. Among the conclusions were: (1) NO donor SNAC improves the microcirculation of denervated skeletal muscle during early reperfusion; and (2) this protection against reperfusion injury is independent of innervation in skeletal muscle. 相似文献
84.
Wang F Wera G Knoblich GO Chou LB 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2002,23(5):406-410
The risks of thromboembolism following operative treatment of ankle fractures are deep vein thrombosis (DVT) and pulmonary embolism (PE). These are potentially life-threatening complications. Many orthopedic surgeons fail to appreciate the potential complications of thromboembolic events because of their rare and delayed occurrence in foot and ankle operations. The purpose of this report is to describe the potential for DVT and PE following ankle operations. We present three cases in which patients who underwent operative treatment of ankle fractures subsequently developed PE. We also review the literature on the prevalence of thrombosis, risk factors, methods of prophylaxis, and use of prophylaxis in surgical procedures of the lower extremity. 相似文献
85.
儿童颈椎间盘钙化的诊断和治疗 总被引:2,自引:0,他引:2
目的 探讨儿童颈椎间盘钙化诊断和治疗的有效方法。方法 回顾性分析13例儿童的颈椎间盘钙化,其中上感后颈痛5例,外伤后偶然发现2例,突发颈部疼痛3例,突发斜颈3例。所有患者均经颈椎正、侧位X片证实。伴有疼痛症状应用非甾体抗炎镇痛药类药物,对于颈部症状较重则予预围外固定或短暂牵引后颈围外固定3-4周。结果 13例患儿共发现14个椎间隙的颈椎间盘钙化。经对症处理后临床症状均消失,所有的钙化均于5个月内完全消失。结论 儿童颈椎间盘钙化是一良性自限性疾病,正确认识其病理生理过程,可避免不必要的手术创伤。 相似文献
86.
OBJECTIVE: We evaluated the cardiovascular injury induced by ischemia and reperfusion (I/R) of the liver by measuring changes in blood levels of cardiac troponin I (cTNI), an index of cardiovascular injury, as well as levels of selected indicators of an inflammatory response. MATERIALS AND METHODS: Ischemia was induced in the rat liver by clamping the common hepatic artery and portal vein for 40 minutes, after which flow was restored, and the liver reperfused for 90 minutes. Blood samples were collected prior to ischemia and after reperfusion. cTNI as well as levels of tumor necrosis factor alpha (TNFalpha), hydroxyl radical (.OH), nitric oxide (NO), and alanine transferase (ALT) were measured. RESULTS: I/R of the liver induced a significant increase in ALT (P<.001). Increased cTNI levels (P<.05) were associated with inflammatory responses, such as elevated levels of TNFalpha (P<.001), . OH (P<.001), and NO (P<.001). After administration of 3-aminobenzamide, a poly(ADP-ribose) polymerase (PARP) inhibitor, liver and heart injuries were significantly attenuated (P<.05). CONCLUSIONS: I/R-induced liver injury was associated with cardiovascular injury, perhaps resulting from inflammatory responses triggered by elevated levels of reactive radical species of nitric oxide, superoxide, and peroxynitrite, by which PARP was activated. 3-Aminobenzamide, significantly attenuated I/R-induced liver and heart injuries. 相似文献
87.
BACKGROUND: Endoscopic thoracic sympathectomy or sympathicotomy of the lower part of the stellate ganglion is an efficient method for the treatment of craniofacial hyperhidrosis, but postoperative compensatory sweating may be troublesome in some patients. Needlescopic thoracic sympathetic block by clipping may achieve a similar effect as well as providing a possible reverse operation for patients who suffer from intolerable postoperative compensatory sweating. METHODS: Between January 1998 and June 2000, we collected a total of 28 patients with craniofacial hyperhidrosis. There were 15 men and 13 women with a mean age of 39.2 years (ranges, 19-50). All patients were placed under single-lumen intubated anesthesia in a semisitting position. Two ports were needed. We used a 2-mm 0 degrees thoracoscope and endo clips to perform a sympathetic block by clipping the lower third of the stellate ganglion at the second intercostal space. RESULTS: The operation was usually accomplished within 20 min (ranges, 15-30). All patients were discharged within 4 h after the operation. There were no surgical complications or surgical mortality cases. All patients achieved improvement of craniofacial hyperhidrosis without recurrent symptoms after a mean of 25.3 months (range, 12-41) of follow-up. Twenty-five patients (85.7%) developed compensatory sweating of the trunk and lower limbs. One of these patients could not tolerate this postoperative sweating; he therefore underwent a reverse operation and obtained improvement of the compensatory sweating 18 days after removal of the endo clips. CONCLUSION: Needlescopic thoracic sympathetic block by clipping is a safe and effective method for the treatment of craniofacial hyperhidrosis; compensatory sweating may be improved after a reverse operation and removal of the endo clips. 相似文献
88.
BACKGROUND/AIM: Uremic patients are at an increased risk of being affected by tuberculosis (TB). Periodical tuberculin skin tests were suggested to detect TB-infected patients. These were replaced by chest radiographs in endemic areas like Taiwan. However, almost 50% of the TB incidence in dialysis patients was extrapulmonary. In this study, we tried to investigate the value of tuberculin tests in dialysis patients in endemic areas. METHODS: The patients were recruited from our dialysis unit. Purified protein derivative (PPD) and control tests with antigens for Candida and toxoid were performed using the Mantoux method. PPD with >10-mm induration will be considered positive. Skin anergy meant that the indurations of all antigens were less than 5 mm. A follow-up was done 12 months after the tests. RESULTS: A total of 177 patients were evaluated. Anergy was found in 40 patients (22.6%). A positive predictor of anergy was age >45 years (p = 0.03), while a negative predictor was prealbumin >20 mg/dl (p = 0.04). Fifty-three patients (30%) had positive PPD tests. Seven of the positive PPD patients (13.2%) developed active TB during the following years. Among the 40 patients with skin anergy, 6 (15%) were found to have active TB. Of the 48 patients (21.1%) with indurations of the PPD tests between 5 and 10 mm, none was found to have active TB. CONCLUSION: Although anergy will influence the sensitivity of PPD tests, these tests in combination with anergy tests could help to establish the diagnosis of TB in uremic patients, even in TB-endemic areas. 相似文献
89.
Effect of pretreatment with ketorolac on propofol injection pain 总被引:2,自引:0,他引:2
Huang YW Buerkle H Lee TH Lu CY Lin CR Lin SH Chou AK Muhammad R Yang LC 《Acta anaesthesiologica Scandinavica》2002,46(8):1021-1024
BACKGROUND: : Pain on injection is still a major problem with propofol. We performed this study to compare different doses of intravenous (i.v.) ketorolac with and without venous occlusion and its effect on the incidence and the severity of the pain after propofol injection. METHODS: We conducted a prospective, randomized and double-blind study of 180 patients (20-60 years of age.) scheduled to undergo elective surgery. Six groups of patients were generated: group A received normal saline (NS) 2 ml i.v.; groups B, C, D received ketorolac 10 mg in 2 ml NS with venous occlusion (VO) and a subsequent propofol injection at either 30, 60 or 120 s; groups E and F received ketorolac 15 mg and 30 mg in 2 ml NS and propofol was injected after 60 s. The pain perception was assessed during injection of propofol in all patients. RESULT: : The incidence of propofol-associated injection pain was for A: 46.7%; B: 43.4%; C: 23.3%; D:16.7%; E: 20%, and F: 10%. The incidence of pain following propofol injection was reduced by i.v. ketorolac 10 mg with venous occlusion for 120 s. Furthermore, i.v. ketorolac 15 mg and 30 mg but not 10 mg following propofol injection after 60 s without venous occlusion revealed significant pain reduction when compared to saline group. There was no difference in venous sequelae at 7 days postoperatively between the groups. CONCLUSION: Our results suggested that pretreatment with i.v. 15 and 30 mg ketorolac reduces pain following propofol injection. Moreover, pretreatment with i.v. ketorolac 10 mg with venous occlusion for 120 s achieves the same pain relief effect. 相似文献
90.
S.-S. Wang N.-K. Chou S.-C. Huang C.-H. Wang Y.-S. Chen W.-J. Ko 《Transplantation proceedings》2010,42(3):938-939