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51.
Malignant peripheral nerve sheath tumor is a rare neurogenic tumor that usually presents in geriatic patients. Typically, it is found in the trunk and extremities and rarely presents in the head and neck region. It may mimic a carotid body tumor when it presents in the neck. We report the first case of malignant peripheral nerve sheath tumor of the vagus nerve in an adolescent boy. He presented with an asymptomatic lateral neck lump that was thought to be a benign schwannoma on preoperative imaging. We describe the diagnostic dilemma and management difficulties in this patient and review the literature.  相似文献   
52.
高位腰椎间盘突出症   总被引:2,自引:0,他引:2  
目的:通过147例高位腰椎间盘突出症的回顾性研究,旨在提高对本症的认识,减少漏诊,误诊,方法:回顾性分析报告147例高位腰椎间盘突出,结果:治疗腰1,210例,腰2。3 32例,腰3,4 105例,其中双间隙突出34例,跳跃性突出27例,伴椎管狭窄31例。瘫痪3例,非手术治疗34例,手术113例,优47例,良8例,差92例,重点讨论了高位腰椎及椎间盘和神经根的解剖特点和临床三大特征及诊断治疗,提出对不同程度的病人用不同治疗方式以及手术中需要注意的六个问题。  相似文献   
53.
PURPOSE: We examined the association of diabetes and domains of sexual dysfunction in a population based sample of men residing in Olmsted County, Minnesota. MATERIALS AND METHODS: A cohort of 2,115 white men 40 to 79 years old as of January 1, 1990 was randomly selected from the Olmsted County population. Men who had a history of prostate or bladder surgery, urethral surgery or stricture, or medical or other neurological condition that could affect normal urinary function were excluded from analysis. Diabetes itself was not used as an exclusionary criterion, although those with end stage organ failure as a result of diabetes were excluded. A previously validated male sexual function index was included in the questionnaires administrated to the cohort in 1996, which consisted of 11 questions on the 5 sexual function domains of sexual drive, erectile function, ejaculatory function, sexual problem assessment and sexual satisfaction. The baseline questionnaire also included whether they had ever been diagnosed by a physician as having diabetes. Only men with regular sexual partners were included. RESULTS: Individuals with diabetes at baseline had significantly greater dysfunction in all 5 sexual function domains. In multivariate adjusted analyses diabetes was significantly associated with all sexual dysfunction domains. The associations remained significant after adjusting for numerous predictors of sexual dysfunction. CONCLUSIONS: The presence of diabetes at baseline was significantly associated not only with erectile dysfunction but with all aspects of sexual dysfunction, including sexual drive, ejaculatory function, sexual problems and sexual satisfaction in this population based sample of men residing in Olmsted County.  相似文献   
54.
Background Trocar incisions are important sources of pain the first days after laparoscopic cholecystectomy. Radially expanding trocars may cause less pain than conventional cutting trocars. Methods In a patient- and observer-blinded trial, 80 patients were randomized to undergo laparoscopic cholecystectomy using either radially expanding trocars (radial group) or conventional cutting trocars (cutting group). Two 10-mm and two 5-mm trocars were used in both treatment groups. All the patients received standardized anesthetic and analgesic treatment. The primary outcome was incisional pain. Pain was registered during mobilization using a visual analog scale (VAS) and a verbal rating scale (VRS) before and 6 h after the operation, and at postoperative days 1 and 2. The needs for a fascial incision to retract the gallbladder, active surgical hemostasis, and supplementary requirements of opioids during the hospital stay were registered. In addition, 2 days after the operation, the incidence and severity of suggilations at the trocar incisions were measured. Results Data from 77 patients were available for statistical analysis. In the radial group, 23 patients needed fascial incision for gallbladder retraction compared with 11 patients in the cutting group (p = 0.006). No significant intergroup differences in VAS or VRS pain scores or any other variable were found. Conclusions The use of radially expanding trocars has no effect on incisional pain after laparoscopic cholecystectomy.  相似文献   
55.
BACKGROUND: Reoperations after intertrochanteric fractures are often necessitated by fracture displacement following mobilization of the patient. The biomechanical complexity of the fracture, the position of the implant, and the patient's characteristics are known to influence postoperative outcome. We investigated the importance of an intact lateral femoral wall as a factor in postoperative fracture displacement after fixation with a sliding compression hip screw. METHODS: Two hundred and fourteen consecutive patients with an intertrochanteric fracture were treated with a 135 degrees sliding compression hip screw with a four-hole side-plate between 2002 and 2004. The fractures were classified on preoperative radiographs according to the AO/OTA classification system. The status of the greater and lesser trochanters, the integrity of the lateral femoral wall, and the position of the implant were assessed postoperatively. Reoperations due to technical failure were recorded for six months postoperatively. RESULTS: Only 3% (five) of 168 patients with an intact lateral femoral wall postoperatively underwent a reoperation within six months, whereas 22% (ten) of forty-six patients with a fractured lateral femoral wall were operated on again (p < 0.001). Multivariate logistic regression analyses combining demographic and biomechanical parameters showed a compromised lateral femoral wall to be a significant predictor of a reoperation (p = 0.010). Seventy-four percent (thirty-four) of the forty-six fractures of the lateral femoral wall occurred during the operative procedure itself. A fracture of the lateral femoral wall occurred in only 3% (three) of the 103 patients with an AO/OTA type-31-A1.1, A1.2, A1.3, or A2.1 intertrochanteric fracture compared with 31% (thirty-one) of the ninety-nine with an AO/OTA type 31-A2.2 or A2.3 fracture (p < 0.001). CONCLUSIONS: A postoperative fracture of the lateral femoral wall was found to be the main predictor for a reoperation after an intertrochanteric fracture. Consequently, we concluded that patients with preoperative or intraoperative fracture of the lateral femoral wall are not treated adequately with a sliding compression hip-screw device, and intertrochanteric fractures should therefore be classified according to the integrity of the lateral femoral wall, especially in randomized trials comparing fracture implants.  相似文献   
56.
ObjectiveTo evaluate the effect of body mass index (BMI) on the outcomes of patients with urinary tract carcinoma treated with radical surgery.Materials and methodsData were collected from 10 Canadian centers on patients who underwent radical cystectomy (RC) (1998–2008) or radical nephroureterectomy (RNU) (1990–2010). Various parameters among subsets of patients (BMI<25, 25≤BMI<30, and BMI≥30 kg/m2) were analyzed. Kaplan-Meier and multivariate analyses were performed to assess the effect of BMI on overall survival, disease-specific survival, and recurrence-free survival (RFS).ResultsAmong the 847 RC and 664 RNU patients, there was no difference in histology, stage, grade, and margin status among the 3 patient subsets undergoing either surgery. However, RC patients with lower BMIs (<25 kg/m2) were significantly older (P = 0.004), had more nodal metastasis (P = 0.03), and trended toward higher stage (P = 0.052). RNU patients with lower BMIs (<25 kg/m2) were significantly older (P = 0.0004) and fewer received adjuvant chemotherapy (P = 0.04) compared with those with BMI≥30 kg/m2; however, there was no difference in tumor location (P = 0.20), stage (P = 0.48), and management of distal ureter among the groups (P = 0.30). On multivariate analysis, BMI was not prognostic for overall survival, disease-specific survival, and RFS in the RC group. However, BMI≥30 kg/m2 was associated with more bladder cancer recurrences and worse RFS in the RNU group (HR = 1.588; 95% CI: 1.148–2.196; P = 0.0052).ConclusionsIncreased BMI did not influence survival among RC patients. BMI≥30 kg/m2 is associated with worse bladder cancer recurrences among RNU patients; whether this is related to difficulty in obtaining adequate bladder cuff in patients with obesity requires further evaluation.  相似文献   
57.
An ion exchange method has been developed to separate no-carrier-added 64Cu from irradiated Ni target. The target is first dissolved in nitric acid and the solution is evaporated to dryness and the residue is dissolved in an ethanol–HCl solution. Cu, Co and Ni in ethanol–HCl solution are then absorbed on an anion exchange column. Co and Ni are removed from the column by eluting with 72% ethanol–0.3 mol/l HCl. Finally, the 64Cu is eluted with water. For separating Ni from Co isotopes and recovering the 64Ni target, the eluate of 72% ethanol–0.3 mol/l HCl is evaporated to dryness, the residue is dissolved in a concentrated HCl solution, and loaded to an another column, Ni is eluted by 9 mol/l HCl, while Co remains on the column. The procedure developed has been successfully applied for the production of no-carrier-added 64Cu from enriched 64Ni generated by the reaction 64Ni(p, n)64Cu using a cyclotron. The decontamination of Co in Cu fraction is higher than 99% and recoveries of 64Cu and 64Ni are higher than 95%.  相似文献   
58.
OBJECTIVE: The final outcome of patients with small cell lung cancer (SCLC) is poor with an overall 5-year survival rate of less than 10%. Therefore, the question of surgery in patients with a technically-operable solitary tumor has been raised. The purpose of this study was to identify the proportion of patients with operable SCLC and to assess the prognosis of different treatment strategies. For patients who were operated, we compared the resection specimens from patients with more than 5-year survival with those with shorter survival to see whether the specimens belonged to different subclasses of SCLC. METHODS: In Norway all clinical and pathologic departments submit reports on cancer patients to the Cancer Registry. The Registry also has a law-regulated authority to collect supplemental information regarding diagnosis, treatment and outcome for all cancer patients from the hospitals in charge. All reports on patients diagnosed as having SCLC in limited disease or unknown stage during the time interval 1993-1999 were reviewed. Patients with a T2-tumor, in whom a pneumonectomy would have to be performed, were classified as potentially operable. Five-year relative survival was calculated for patients diagnosed in 1993-1997. RESULTS: During the actual period 2442 individuals with SCLC were identified. The majority was treated with conventional chemotherapy or concurrent chemoradiotherapy while 38 underwent surgical therapy. Following reclassification of 697 patients reported to have limited disease or unknown stage 180 were judged to be in stage I. In addition to the 38 resected patients 14 were considered fit for surgery technically and medically while 97 were found to be potentially operable treatment modalities apart from surgery yielded a 5-year survival rate <7%. For stage I (N=96) the rate was 11.3% in conventionally treated patients compared to 44.9% for those who underwent surgical resection. By pathological review of surgical specimens a diagnosis of SCLC was confirmed in all patients treated by surgery in the groups with long and short survival. CONCLUSION: This investigation demonstrates that patients with SCLC having a peripherally located tumor should be referred to surgery, as long time survival is far better than for conventionally treated patients.  相似文献   
59.
The treatment of gastroesophageal reflux (GERD) has improved dramatically in recent years. The new endoluminal treatments may bring a relatively simple, minimally invasive therapy that can be simultaneously applied in patients with GERD undergoing diagnostic upper endoscopy. Although the initial results are promising, these new techniques are generating some controversy and require further evaluation with randomized studies and longer follow-ups to define their precise role in the long-term management of the gastroesophageal reflux disease.  相似文献   
60.
To determine whether reactive oxygen molecules could directly and reversibly increase the transfer of albumin across an endothelial barrier, we measured albumin transfer across monolayers of endothelium cultured on micropore filters before and after exposure to xanthine and xanthine oxidase. Xanthine and xanthine oxidase increased endothelial albumin transfer in a dose-dependent fashion. Parallel phase contrast and fluorescence microscopy demonstrated retraction of adjacent cells from one another and disruption of the actin filaments. The oxidant- induced increases in albumin transfer and changes in cell shape were reversed by removing xanthine oxidase and then incubating the monolayers for 3 1/2 hours in tissue culture media enriched with fetal bovine serum. However, incubation in tissue culture media without serum resulted in progressive injury and cell death. Hence, the brief exposure to oxidants initiated a progressive injury process that was reversed by incubation in serum. Because intracellular and extracellular calcium are important determinants of cell shape, and because some oxidized membrane lipids act as calcium ionophores, we asked whether oxidants altered endothelial calcium homeostasis. Xanthine-xanthine oxidase increased release of 45Ca++ from preloaded cells. The calcium antagonist lanthanum chloride prevented xanthine- xanthine oxidase increases in endothelial albumin transfer and prevented the changes in cell shape; chelation of extracellular calcium inhibited lysis of endothelium by xanthine-xanthine oxidase; and the calcium ionophore A23187 increased endothelial albumin transfer and mimicked the oxidant-induced changes in cell shape. Lanthanum chloride inhibited these effects of A23187. These data suggest that oxygen radicals can reversibly increase endothelial permeability to macromolecules, that this is associated with reversible changes in endothelial cell shape and actin filaments, and that the changes in cell shape are related to oxidant-induced changes in endothelial calcium homeostasis.  相似文献   
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