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31.
以家犬驱虫为中心的棘球蚴病控制措施在新疆两县的应用   总被引:1,自引:1,他引:1  
目的 通过新疆呼图壁县和温宿县区域试验,验证以家犬(包括牧犬)驱虫为中心的棘球蚴病控制措施的可行性和控制效果。 方法 1987-1990年在新疆呼图壁县和1990-1994年在新疆温宿县分别建立棘球蚴病控制试验区,采用消灭病原以阻断循环链的控制策略,即“犬犬驱虫、 月月投药”的措施,对试验区所有家犬用吡喹酮药饵剂型进行预防性驱虫。实施控制措施后,每年在试验区检测犬的细粒棘球绦虫和绵羊的棘球蚴感染率,以评价驱虫效果。 结果 经过连续3~4年实施“犬犬驱虫、月月投药”措施,呼图壁县和温宿县的家犬细粒棘球绦虫平均感染率分别从实施前的18.5%和14.7%降为0;两县新生绵羊的棘球蚴平均感染率比控制模式实施前降低了85%以上。 结论 以家犬驱虫为中心的策略,即“犬犬驱虫,月月投药”的措施对控制家犬的棘球绦虫病和绵羊的棘球蚴病是有效可行的。  相似文献   
32.
PV Isolation Using Bipolar/Unipolar RF Energy . Background: Electrical disconnection of the pulmonary veins (PV) plays an important role in the ablation of paroxysmal atrial fibrillation (AF). Antral ablation using a conventional steerable ablation catheter often is technically challenging and time consuming. Methods: Eighty‐eight patients (mean age 58 ± 11 years) with symptomatic paroxysmal AF underwent ablation with a circular mapping/ablation decapolar catheter (PVAC). Ablation was performed in the antral region of the PVs with a power‐modulated bipolar/unipolar radiofrequency (RF) generator using 8–10 W delivered simultaneously through 2–10 electrodes, as selected by the operator. Seven‐day Holter monitor recordings were performed off antiarrhythmic drugs at 3‐, 6‐, and 12‐month follow‐up, and patients were requested to visit the hospital in the event of ongoing palpitations. All follow‐up patients were divided into 2 groups: Group 1 with a follow‐up of less than 1 year and group 2 patients completing a 1‐year follow‐up. Results: Overall, 338 of 339 targeted PVs (99%) were isolated with the PVAC with a mean of 24 ± 9 RF applications per patient, a mean total procedure time of 125 ± 28 minutes, and a mean fluoroscopy time of 21 ± 13 minutes. Freedom from AF off antiarrhythmic drugs was found in 82 and 79% of group 1 and group 2 patients, respectively. No procedure‐related complications were observed. Conclusion: PV isolation by duty‐cycled unipolar/bipolar RF ablation can be effectively and safely performed with a circular, decapolar catheter. Twelve‐month follow‐up data compare favorably with early postablation results, indicating stable effects over time. (J Cardiovasc Electrophysiol, Vol. 21, pp. 399–405, April 2010)  相似文献   
33.
Comparison of Radiofrequency Versus Conventional Catheter Ablation. Introduction: Radiofrequency (RF) catheter ablation has been established as an effective and curative treatment for atrial flutter (AFL). Approved methods include a drag‐and‐drop method, as well as a point‐by‐point ablation technique. The aim of this study was to compare the acute efficacy and procedural efficiency of a multipolar linear ablation catheter with simultaneous energy delivery to multiple catheter electrodes against conventional RF for treatment of AFL. Methods: Patients presenting to our department with symptomatic, typical AFL were enrolled consecutively and randomized to conventional RF ablation with an 8‐mm tip catheter (ConvRF) or a duty‐cycled, bipolar‐unipolar RF generator delivering power to a hexapolar tip‐versatile ablation catheter (T‐VAC) group. For both groups, the procedural endpoint was bidirectional cavotricuspid isthmus block. Results: Sixty patients were enrolled, 30 patients each assigned to ConvRF and T‐VAC groups. Total procedure time (40.2 ± 15.8 min vs 60.5 ± 12.7 min), energy delivery time (8.5 ± 3.7 min vs 14.7 ± 5.2 min), radiation dose (14.5 ± 3.5 cGy/cm2 vs 31.7 ± 12.1 cGy/cm2), and the minimum number of RF applications needed to achieve block (4.2 ± 2.4 vs 8.9 ± 7.2) were significantly lower in the T‐VAC group. In 7 patients treated with the T‐VAC catheter, bidirectional block was achieved with less than 3 RF applications, versus no patients with conventional RF energy delivery. Conclusion: The treatment of typical AFL using a hexapolar catheter with a multipolar, duty‐cycled, bipolar‐unipolar RF generator offers comparable effectiveness relative to conventional RF while providing improved procedural efficiency. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1109‐1113)  相似文献   
34.
Background: Complications of transcatheter closure of atrial septal defects (ASDs) include pericardial effusion, tamponade, and even death. Transthoracic echocardiography in the adult is often limited by poor acoustic windows that lead to incomplete device assessment. Advances in multislice computed tomography (MSCT) provide an alternative modality to assess the anatomy of the Amplatzer Septal Occluder (ASO) device.
Objective: The purpose of this study was to determine the feasibility of MSCT in providing anatomic information in patients with persistent or recurrent symptoms after transcatheter closure of ASDs with ASO devices.
Methods: A retrospective analysis of adult patients who underwent ASO device implantation with subsequent MSCT imaging as a result of symptoms from June 2006 to May 2007 was performed. Data analysis included age, gender, size of ASO device, relationship of the device to surrounding structures, symptoms, and the length of time between device implantation and onset of symptoms.
Results: Eleven patients were identified with a mean age of 41 years. Patients presented with symptoms 1 week to 2.4 years after implantation. ASO size ranged from 8 to 36 mm. MSCT provided detailed information in all 11 cases regarding anatomic location of the device with respect to surrounding structures. Nonobstructive coronary plaque disease was identified in one patient. Two patients had pericardial effusions.
Conclusions: Cardiac symptoms after ASO implant deserve thorough investigation. MSCT is feasible in the assessment of such patients and offers a unique assessment of the device to surrounding anatomic structures and should be considered as a useful adjunct to echocardiography in symptomatic patients.  相似文献   
35.
磷脂酶A2在中性粒细胞肺内聚集损伤中的作用   总被引:2,自引:0,他引:2  
磷脂酶A2在中性粒细胞肺内聚集损伤中的作用刘松殷凯生朱荣刘立杨玉探讨急性肺损伤(ALI)时,磷脂酶A2(PLA2)在多核中性粒细胞(PMN)肺内聚集和活化以及所造成损伤中的作用。材料与方法体重160~245g健康SD大鼠36只,随机分空白对照组(Ⅰ组...  相似文献   
36.
Molecular Genetic Basis of Hypertrophic Cardiomyopathy:   总被引:5,自引:1,他引:5  
Genetics of SCD in HCM. Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disease caused by mutations in sarcomeric proteins. The disease is characterized by left ventricular hypertrophy in the absence of an increased external load, and myofibrillar disarray. A large number of mutations in genes coding for the β-myosin heavy chain (β-MyHC), cardiac troponin T (cTnT), cardiac troponin I, α-tropomyosin, myosin binding protein C (MyBP-C), and myosin light chain 1 and 2 in patients with HCM have been identified. Genotype-phenotype correlation studies have shown that mutations carry prognostic significance. The Gly256Glu, Val606Met, and Leu908Val mutations in the μ-MyHC are associated with a benign prognosis. In contrast, Arg403Gln, Arg719Trp, and Arg453Cys mutations are associated with a high incidence of sudden cardiac death (SCD). Mutations in cTnT are associated with a mild degree of hypertrophy, but a high incidence of SCD. Mutations in MyBP-C are associated with mild hypertrophy and a benign prognosis. However, it has become evident that factors other than the underlying mutations, such as genetic background and possibly environmental factors, also modulate phenotypic expression of HCM.  相似文献   
37.
Summary. Background: Acquired hemophilia A (AHA) is a severe life‐threatening autoimmune disease due to the development of autoantibodies that neutralize the procoagulant activity of factor VIII (FVIII). In rare cases, AHA occurs in the postpartum period as a serious complication of an otherwise normal pregnancy and delivery. Due to its rarity, little is known about the features of the antibody response to FVIII in AHA. Objectives: Our study wanted to (i) determine the epitope specificity and the immunoglobulin (Ig) subclasses of anti‐FVIII autoantibodies in plasma samples from a large cohort of AHA patients, and (ii) compare the epitope specificity of anti‐FVIII autoantibodies in plasma samples from postpartum AHA and other AHA patients. Patients/Methods: Seventy‐three plasma samples from patients with postpartum AHA (n = 10) or associated with malignancies (n = 16) or autoimmune diseases (n = 11) or without underlying disease (n = 36) were analyzed with three multiplexed assays. Results and Conclusions: Our results showed a stronger response against the A1a1‐A2a2‐B fragments of FVIII and more specifically against the A1a1 domain in patients with postpartum AHA than in the other AHA groups (P < 0.01). Moreover, although IgG4 was the predominant IgG subclass in all groups, anti‐A1a1‐A2a2‐B and anti‐A1a1 domain autoantibodies of the IgG1 and IgG3 subclasses were more frequently detected in postpartum AHA than in the other AHA groups. These findings support the involvement of the Th1‐driven response in the generation of autoantibodies in women with postpartum AHA compared with the other groups of AHA patients in whom production of Th2‐driven IgG4 was predominant.  相似文献   
38.
Background: Neointimal formation and vascular remodeling are major mechanisms contributing to coronary restenosis after percutaneous transluminal coronary angioplasty. Intracoronary γ- and β-radiation have been shown to inhibit neointimal formation in balloon-injured porcine coronary arteries. However, the effects of Intracoronary radiation (ICR) dose and dose rate on vascular remodeling versus inhibition of neointimal formation have not been evaluated. Methods and Results: Forty-one Hanford Miniature swine were subjected to oversized balloon injury in the left anterior descending and right coronary artery. A spiral centering catheter with perfusion capabilities was placed in the injured segment for circumferentially uniform radiation dose delivery to the vessel wall. Each artery was randomly afterloaded with a dummy wire or an active wire with the 32P source encapsulated in either a short (3 mm) or long (27 mm) segment at the distal end of the wire. The 3-mm source wire was used to deliver 650, 1,300, and 1,900 cGy while the 27-mm source wire was used to deliver 1,200 and 3,500 cGy of β-radiation to the adventitia (~ 0.5 mm into the vessel wall). The dose rate for ICR varied from 2.5 to 140 cGylsec, depending on the mCi strength of the 32P source at the time of endovascular radiation. One month later, repeat coronary angiography and intravascular ultrasound (IVUS) to measure the external elastic lamina (EEL) area were done. The animals were sacrificed and the coronary vasculature was perfusion fixed. Morphometric, quantitative coronary angiographic, and IVUS analyses were carried out in a blinded fashion. A significant reduction in percent area stenosis (PAS) and neointimal area (NA) was observed on morphometry in coronary arteries treated with 3,500 cGy of β-radiation. The PAS and NA was 44%± 13% and 0.96 ± 0.25 mm2 in the control groups versus 19%± 14% and 0.30 ± 0.23 mm2 in the 3,500-cGy group (P < 0.02). There was no significant difference on morphometry between the control and the other four β-radiationtreated groups. There was no significant improvement in the change in minimum lumen diameter (ΔMLD) between the control and the five radiation-treated groups. Further analysis of angiographic data revealed that the apparent lack of beneficial effect on angiography was due to significant reductions in lumen diameter in the subgroups of arteries subjected to ICR at a dose rate > 50 cGylsec with the 3-mm source wire only. The ΔMLD was -1.39 ± 0.49, –1.79 ± 0.64, and -1.79 ± 0.39 mm in the 650-, 1,300-, and 1,900-cGy groups treated with a dose rate > 50 cGylsec versus -0.56 ± 0.95 in control (P < 0.05). This reduction in lumen diameter on angiography was associated with a significant reduction in vessel (EEL) area especially in the groups treated with the 3 mm source at a dose rate > 50 cGylsec. The EEL area was 8.8 ± 1.7, 9.9 ± 1.7, and 8.9 ± 0.6 mm2 in the 650, 1,300, and 1,900 cGy groups treated at a dose rate > 50 cGylsec compared to 11.7 ± 1.6 mm2 in control arteries (P < 0.001). Conclusions: Endovascular β-radiation at high doses (3,500 cGy to adventitia) and dose rate < 50 cGylsec inhibits restenosis after balloon injury in the porcine model of coronary restenosis. This dose and dose rate is associated with a neutral effect on vascular remodeling. While lower doses of ICR did not worsen the PAS, a reduction in MLD and EEL area were observed. However, this adverse effect on angiographic restenosis and vascular remodeling appears to be largely limited to the subgroups treated at dose rates > 50 cGylsec.  相似文献   
39.
Pain is one of the most troublesome complications of tonsillectomy. The pain appears as throat pain, otalgia, or both, and continues until mucosal recovery on the tonsillar fossae is complete. Some surgical and hemostasis techniques may increase pain. Analgesics, antibiotics, steroids, and local and topical anesthetics are used to relieve posttonsillectomy pain, but none has the desired effectiveness. The pain reliever must not increase bleeding and must have minimal side effects. Sucralfate, a basic amino salt of sucrose octasulfate, binds to the matrix protein of a peptic ulcer and produces a protective barrier. Tonsillectomy leaves two large ulcerous wounds, and sucralfate may bind those wounds as it does peptic ulcers. In this controlled study, the efficacy of sucralfate on posttonsillectomy throat pain, otalgia, analgesic requirement, degree of strength, bleeding, body temperature, and mucosal recovery is investigated in 80 patients. Sucralfate is found to significantly reduce throat pain and analgesic requirement after surgery. (Otolaryngol Head Neck Surg 1998;119:700-4.)  相似文献   
40.
Metastatic Carcinoma Simulating Linitis Plastica of the Colon   总被引:2,自引:0,他引:2  
Reported herein is the case of a 70-year old woman with metastatic breast carcinoma presenting as linitis plastica of the ascending colon. The breast tumor was diagnosed nine years previously. The clinical, roentgenographic and pathologic features of colonic linitis plastica and the preoperative diagnostic difficulties are discussed. There is no difference in the morphologic features of primary and secondary linitis plastica. The latter may result from anaplastic carcinoma of the stomach, gallbladder or breast.  相似文献   
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