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51.
ABSTRACT: We report our initial experience with the modular AneuRx Stent Graft System for the treatment of infrarenal abdominal aortic aneurysm (AAA) in National Taiwan University Hospital. From July 2002 to October 2003, 5 patients were recruited for stent graft repair. Patients were all male, and aged from 62 to 82 years. The stent grafts were deployed via the opened femoral arteries under fluoroscopic guidance. Endograft deployment was successful in all 5 patients. The average procedure time was 139 +/- 23 min, and mean blood loss was 310 +/- 167 mL. All patients had a smooth postoperative course. Type II endoleak was noted in 3 patients initially, which sealed spontaneously in 2 of them. One patient developed graft limb thrombosis 1 month after operation, which was treated by femoral-femoral bypass. Treatment was successful in all patients with no mortality during 1-year postoperative follow-up.  相似文献   
52.
OBJECTIVE: To investigate the influence of inserting a Fuji pressure sensitive film between the tibiofemoral joint of knee prosthesis on actual contact characteristics. DESIGN: A finite element analysis was used to investigate the alteration of contact characteristics of the tibiofemoral joint due to inserting a pressure sensitive film between the contacting surfaces. BACKGROUND: The discrepancy between actual contact behaviors of tibiofemoral joint of knee prosthesis and the measurement using Fuji pressure sensitive film was not discussed extensively. The change of direct contact circumstance of the tibiofemoral joint due to inserting a pressure sensitive film was not well reported. METHOD: A two-dimensional finite element model of the tibiofemoral joint of knee prosthesis in the sagittal plane was constructed. Four different radii of the femoral component were used to investigate the conformity effect. Two-layers of plane strain element were used to model the pressure sensitive film. The influence of inserting a pressure sensitive film on the actual contact characteristics was analyzed by comparing the results of the change in contact radius. RESULTS: Inserting a pressure sensitive film between contacting surfaces would disturb the original contact behaviors, especially in the lowest conformity design. The maximum difference of contact radius between the model simulating actual contact circumstance and the model with inserting a pressure sensitive film between contacting surface was 77% in the lowest conformity condition at the smallest load. CONCLUSIONS: This study proposes a quantitative analysis of contact characteristics in the tibiofemoral joint of knee prosthesis between the models with and without inserting a pressure sensitive film into the contact surface. The measurement of contact area in artificial tibiofemoral joints by using Fuji pressure sensitive film is always overestimated its true contact area by 14-77%. RELEVANCE: This study revealed the measurement of contact characteristics of artificial tibiofemoral joints by using Fuji pressure sensitive film which depends on not only the applied load, but also the conformity and material properties of the contact surface. Therefore, the information of the conformity and material properties of the contact surface should be provided as well as the applied load wherever a measurement of contact characteristics using Fuji pressure sensitive film is analyzed and interpreted.  相似文献   
53.
Biliary drainage is a radical method to relieve cholestasis, a cause of acute cholangitis, and takes a central part in the treatment of acute cholangitis. Emergent drainage is essential for severe cases, whereas patients with moderate and mild disease should also receive drainage as soon as possible if they do not respond to conservative treatment, and their condition has not improved. Biliary drainage can be achieved via three different routes/procedures: endoscopic, percutaneous transhepatic, and open methods. The clinical value of both endoscopic and percutaneous transhepatic drainage is well known. Endoscopic drainage is associated with a low morbidity rate and shorter duration of hospitalization; therefore, this approach is advocated whenever it is applicable. In endoscopic drainage, either endoscopic nasobiliary drainage (ENBD) or tube stent placement can be used. There is no significant difference in the success rate, effectiveness, and morbidity between the two procedures. The decision to perform endoscopic sphincterotomy (EST) is made based on the patient’s condition and the number and diameter of common bile duct stones. Open drainage, on the other hand, should be applied only in patients for whom endoscopic or percutaneous transhepatic drainage is contraindicated or has not been successfully performed. Cholecystectomy is recommended in patients with gallbladder stones, following the resolution of acute cholangitis with medical treatment, unless the patient has poor operative risk factors or declines surgery.  相似文献   
54.
The purpose of this study is to assess the beneficial effects of a far-infrared-emitting collar (FIRC) on the management of neck disorders. A neck disorder is generalized as neck muscle pain and its relative mental disorders because the etiologies of the neck’s multidimensional syndrome are either muscle impairment or psychiatric distress. This is the first study to determine the efficacy of a FIRC by evaluating objective physical evidence and psychometric self-reports using a parallel-arm randomized sham-controlled and single-blinded design. In this trial, 60 participants with neck disorders were observed at baseline and post-intervention. Compared to the placebo group after a 30-min intervention, the FIRC demonstrated a statistically significant biological effect in elevating skin temperature and promoting blood circulation with p-values 0.003 and 0.020, respectively. In addition, FIRC application significantly reduced neck muscle tension, relieved pain, ameliorated fatigue, improved depression, and decreased anxiety. The FIRC could therefore be a potential treatment for neck disorders.  相似文献   
55.
56.
A novel mutation of isocitrate dehydrogenase-1 (IDH1) was recently found in a large percentage of secondary human gliomas. Unlike previously discovered prognostic molecular characteristics, IDH1 mutations were found across gliomas of many different grades and histologies. Further studies have illuminated its utility as a prognostic marker in low-grade and high-grade gliomas and its ability to aid the differentiation and diagnosis of various tumors with histologic ambiguity. As a metabolic enzyme, its inhibitory actions and neomorphic activity present a unique avenue in the understanding of these tumors and potentially a novel mechanism through which they may be treated.  相似文献   
57.
OBJECTIVES: We previously demonstrated that sphingosine kinase (SPK) increases the level of extracellular sphingosine-1-phosphate and promotes neovascularization in a mouse matrigel model. In this study, we tested the hypothesis that SPK gene transfer using a novel adenoviral 'gutless' vector (AGV) can enhance arteriogenesis in a rabbit hindlimb ischemia model. METHODS: Thirty-five male New Zealand white rabbits were randomized to the AGV-SPK group (n=13), AGV-null group (n=13), and control group (n=9). On day 10, after the induction of unilateral hindlimb ischemia, gene vectors or buffer were introduced and the effect examined on day 30, using calf blood pressure, quantitative angiographic analysis, and histology. RESULTS: Calf systolic blood pressure ratios of the ischemic limb to the normal limb on day 30 were 0.77+/-0.13 in control groups, including the AGV-null group, and 0.91+/-0.14 in the AGV-SPK group (P<0.05). Angiographic vessel counts were significantly increased (8.0+/-2.1 at baseline and 11.8+/-3.2 on day 30, P<0.001) in the AGV-SPK group. Histologic analysis showed that microscopic total vessel counts on day 30 were 3.5+/-1.8/field in the control and AGV-null group and 5.4+/-1.0/field in the AGV-SPK group. Arterioles (AGV-SPK; 3.0+/-0.8 versus control and AGV-null; 2.1+/-1.1, P<0.05) were significantly increased in the AGV-SPK group. CONCLUSIONS: This study shows that SPK promotes arteriogenesis, as evidenced by the maximal improvement in the blood pressure restoration and collateral vessel counts. SPK may be an important angiogenic target to improve perfusion in ischemic tissues.  相似文献   
58.
OBJECTIVE: To determine the relations between left atrial appendage function, spontaneous echo contrast, and thromboembolism in patients with different modes of permanent pacemakers. PATIENTS AND METHODS: 88 patients with pacemaker implantation and 25 healthy controls in sinus rhythm had transoesophageal echocardiographic examination of the left atrial appendage. Left atrial size, appendage area, peak filling and emptying velocities of the atrial appendage, and the presence or absence of spontaneous echo contrast and thromboembolism were determined. The results in 63 patients with ventricular pacing (group 1, subdivided into subgroup 1A: 42 patients with sinus rhythm, and subgroup 1B: 21 patients with atrial fibrillation) were compared with those in 25 patients with synchronous pacing (group 2), and 25 normal control subjects (group 3). RESULTS: Patients with ventricular pacing had two distinct appendage flow patterns: well defined biphasic filling and emptying waves in subgroup 1A, and irregular very low filling and emptying waves in subgroup 1B. The ejection fraction of the left atrial appendage in subgroup 1A was significantly better than that in subgroup 1B (mean (SD) 40.6 (12.0)% v 7.6 (5.0)%, P < 0.0001). The spontaneous echo contrast was observed in 90% of subgroup 1B patients but in only 19% in subgroup 1A (P < 0.05) and was not found in groups 2 and 3 (P < 0.0001). There was a trend for increased prevalence of spontaneous echo contrast in subgroup 1A v group 2 (P = 0.053). Thrombi were detected in two cases, and cardiogenic embolism occurred in one case in subgroup 1B. All patients with spontaneous echo contrast had ventricular pacing. Multivariate analysis showed that atrial fibrillation was associated with occurrence of spontaneous echo contrast in patients with ventricular pacing (P = 0.005). CONCLUSIONS: The left atrial appendage ejection fraction was lower with ventricular pacing than with synchronous pacing. With ventricular pacing there was a trend towards increased prevalence of left atrial spontaneous echo contrast in patients in sinus rhythm, and a significantly increased prevalence in patients with atrial fibrillation.  相似文献   
59.
Two epidemiological surveys of the prevalence of bronchial asthma in schoolchildren in Taipei, Taiwan, were conducted in 1974 and 1985. The same questionnaire and school, and schoolchildren of the same age (7-15 years), were studied in these two surveys. Bronchial asthma was defined as at least three paroxysmal, recurrent attacks of wheezing and dyspnea in the previous 12 months. A total of 23,678 children were studied in 1974 and 147,373 children in 1985. Data from other Asian Pacific countries were also reviewed.

The results: 1) The questionnaire was able to differentiate asthmatics from nonasthmatics on the basis of differences in methacholine challenge, intracutaneous skin testing, total eosinophil count, total serum IgE, and RAST between the two groups. 2) The prevalence of childhood asthma increased from 1.30% in 1974 to 5.07% in 1985, with boys dominating in both studies. 3) The increase in asthma prevalence could not be explained by air pollution or exposure to new allergens. 4) The prevalence of childhood asthma in the Asian Pacific countries are generally comparable to those of Western countries, and the present study and studies from Japan and New Guinea showed an increasing tendency.

Thus childhood asthma is a major problem in the Asian Pacific countries as well as in Western countries.  相似文献   
60.
We present the short- and intermediate-term results of transcatheter closure of patent ductus arteriosus with Gianturco coils in adolescents and adults. During a 5-year period, 55 patients (44 females, 11 males) with ages ranging from 14 to 72 years (median, 23) underwent attempted transcatheter closure of patent ductus with the Gianturco coils. The diameter of the narrowest segment of the ductus ranged from 0.8 to 7.6 mm (3.9 +/- 1.3 mm). The 55 patients were divided into three groups. Group I consisted of nine patients with a ductal diameter < or = 3 mm, group II consisted of 27 patients with a ductal diameter > 3 mm but < or = 4 mm, and group III consisted of 19 patients with a ductal diameter > 4 mm. Four- to five-loop Gianturco coils were used, which were deployed via retrograde aortic route. Multiple-coil technique was generally applied in group II patients. Balloon occlusion technique in combination with multiple-coil technique was generally used in group III patients. Deployment of coil was successful in 51 patients (93%) but failed in 4. The success rate of coil deployment in group I, II, and III were 100% (9/9), 96% (26/27), and 84% (16/19), respectively. A mean of 1.9 +/- 0.7 coils was deployed per patient. Of the four patients with unsuccessful coil deployment, three underwent surgery and one received implantation with Amplatzer duct occluder. Distal embolization of 21 coils occurred in 10 patients (3 in group II and 7 in group III), from whom 20 coils were retrieved with a gooseneck snare and 1 coil was removed during surgery. The mean diameter of ductus in the 10 patients with distal embolization was significantly larger than that in those without (5.2 +/- 1.4 vs. 3.7 +/- 1.1 mm; P < 0.01). Among the 51 patients with successful coil deployment, immediate complete closure was achieved in 20 (39%), while trivial to mild leak was present in 31 (61%). No significant complications were encountered. After a follow-up period ranging from 5 to 42 months, four patients had a small residual shunt and three underwent a second intervention with complete occlusion. None had left pulmonary artery stenosis documented with Doppler echocardiography. Transcatheter closure of ductus with the Gianturco coils is safe and feasible in the majority of adolescents and adults. Taking high embolization rate in patients with a ductus diameter > 4 mm into consideration, controlled-release coils, Buttoned device, or Amplatzer duct occluder can be a better choice.  相似文献   
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