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981.
Background  Left ventricular ejection fraction (LVEF) is a significant predictor of morbidity and death. The nuclear summed rest score (SRS) measures myocardial perfusion defects and provides prognostic information, but its effects on long-term outcomes are not fully established. Moreover, information regarding the potential interaction between these 2 covariates is limited. The purpose of this study was to determine whether the mortality risk associated with LVEF is the same across all values of SRS in a population undergoing evaluation for ischemic heart disease. Methods and Results  We examined 3,187 patients who underwent cardiac catheterization and perfusion single photon emission computed tomography imaging with a maximum follow-up of 8.1 years and median follow-up of 3.1 years. Cox proportional hazards modeling showed that increasing nuclear SRS and decreasing LVEF were independently associated with a higher long-term mortality rate, with a clinically significant interaction between them (P=.032). Patients with a normal LVEF and a high SRS (greater perfusion abnormality) have a prognosis similar to those with a reduced LVEF. Conclusions  Resting perfusion studies provide prognostic information for long-term survival and significantly impact the interpretition of mortality risk associated with changes in LVEF. Patient prognostication, risk stratification, and future research using these variables should take this interaction into account. Supported by a grant from the Tom & Lynn Royster Foundation. Durham, NC, and a National Institutes of Health Research Fellowship Grant (T5 GM08679-04), Bethesda, Md.  相似文献   
982.
电视胸腔镜辅助胸壁小切口肺叶切除术   总被引:13,自引:0,他引:13  
目的比较电视胸腔镜辅助胸壁小切口与胸部单纯小切口肺叶切除术的临床效果. 方法 64例按手术先后顺序编号,按照随机数字表分为2组,电视胸腔镜辅助胸壁小切口(A组)和单纯小切口开胸手术(B组)进行肺叶切除术. 结果 A组切口长度(5.3±0.6)cm比 B组(8.9±0.5)cm显著缩短(t=-24.360,P=0.000);A组术中出血量(279.7±74.0)ml显著少于B组(331.7±42.5)ml(t=-3.330,P=0.002);A组手术当日引流量(162.5±47.4)ml显著少于B组(202.0±49.2)ml(t=-3.220,P=0.002);A组并发症5例,B组11例(χ2=4.099,P=0.043);A组术后住院(8.0±2.2)d显著短于B组(9.7±1.9)d(t=-3.280,P=0.002);2组手术时间无统计学差异(t=-1.130,P=0.262).57例随访6~12个月,术后6个月A组1例Ⅲa期鳞癌局部复发,B组2例Ⅲa期小细胞肺癌、1例腺癌术后7~8个月远处转移、局部复发,上述4例均于1年内死亡.3例死于与手术无关的其他疾病,余50例无局部复发、远处转移. 结论电视胸腔镜辅助胸壁小切口比单纯微创小切口进行肺叶切除术创伤小、并发症少、恢复快.  相似文献   
983.
The purpose of this study is to evaluate the relationship between the magnitude of knee laxity and posterior instability at different knee flexion angles and clinical disability in isolated posterior cruciate ligament (PCL) deficient patients. Knee laxity at 20° and 70° of knee flexion were evaluated using KT-2000 arthrometer, and the posterior instability at 20°, 45° and 90° of flexion were evaluated using stress radiography. We assessed the differences in the knee laxity and the tibial translation between isolated PCL deficient knees and normal knees, and between the patients with giving-way during activities of daily living (ADL) and without giving-way. There were statistical differences in the knee laxity and the tibial translation at all knee flexion angles between the PCL deficient knees and normal knees. The magnitude of the knee laxity at 20° of flexion measured with KT-2000 arthrometer was significantly larger in the patients with giving-way than those in the patients without giving-way although there was no significant difference in the tibial translation at 70° between the two groups. The tibial translation in both medial and lateral compartments at 20° and 45° measured with stress radiography were significantly larger in the patients with giving-way than those in the patients without giving-way although there was not significant difference at 90° between the two groups. These results suggested that the magnitude of the knee laxity and the posterior tibial translation at shallow knee flexion angles would be related to giving-way during ADL in isolated PCL deficient patients.  相似文献   
984.
This in vitro biomechanical study used cadaveric specimens to compare the rotator cuff repair fixation provided by BioCorkscrew and Bioknotless RC suture anchors. Three cm wide by 1-cm long full-thickness supraspinatus defects were repaired using either two BioCorkscrew suture anchors with combined vertical and horizontal mattress sutures (n = 7) or three Bioknotless RC suture anchors with simple sutures (n = 7). Therefore, the BioCorkscrew suture anchor group had two sutures per anchor (four total sutures), while the Bioknotless RC suture anchor group had one suture per anchor (three total sutures). Two-phase cyclic (5–100 N, 1,000 cycles and 5–180 N, 2,000 cycles) and load to failure tests (31 mm/s) were performed. Non-parametric statistics were used to compare group differences (P < 0.05). All of the BioCorkscrew group specimens (seven of seven) completed the two phase cyclic test regimen without failure or gapping ≥ 5 mm, compared to only three of seven of the Bioknotless RC group (Fisher’s Exact test = 0.03). Groups did not differ for repair site gapping during the 5–100 N cyclic test phase (Fisher’s Exact test = 0.77), however more of the Bioknotless RC group displayed gapping ≥ 5 mm during the 5–180 N cyclic test phase than the BioCorkscrew group (P = 0.02). The BioCorkscrew group also displayed greater yield load during load to failure testing (492.2 ± 204 N vs. 296.4 ± 155 N, P = 0.03). In this in vitro biomechanical study, the BioCorkscrew group with combined vertical and horizontal mattress sutures displayed greater cyclic test survival, less repair site gapping, and superior yield load compared to the Bioknotless RC group with simple sutures. These results in human cadaveric rotator cuff-humerus specimens suggest better immediate post-operative repair site strength and a reduced need for post-operative restrictions. Clinical studies are needed to determine how these rotator cuff repair modes withstand the forces of early rehabilitation and activities of daily living that potentially influence patient outcomes.  相似文献   
985.
Wernicke脑病的MRI诊断价值   总被引:1,自引:0,他引:1  
目的探讨Wernicke脑病的MRI表现,以提高诊断水平。方法搜集7例经临床证实的Wernicke脑病的MRI资料进行回顾性分析。结果双侧丘脑、第三脑室周围广泛对称性异常信号(6例),导水管周围、桥脑被盖异常信号(7例),乳头体、丘脑下部、穹隆及四脑室周围异常信号(2例),上述病变呈长T1长T2信号,FLAIR序列呈高信号,2例DWI序列呈高信号,脑室壁模糊,2例静注Gd-DTPA增强后病变区域对比增强,1例可见侧脑室周围小血管放射状强化。结论Wernicke脑病具有典型的MRI表现,对临床诊断及治疗有重要意义。  相似文献   
986.
抗心磷脂抗体与脑血管病关系的研究   总被引:2,自引:0,他引:2  
目的:探讨抗心磷脂抗体(aCL)与脑血管病(CVD)的关系。方法:检测266例缺血性脑血管病(ICVD)患者和73例脑出血(CH)患者血清aCL。结果:ICVD患者aCL阳性率高于对照组(P<0.01),且IgG型aCL比IgM型aCL阳性率升高(P<0.01)。CH患者aCL阳性率高于对照组(P<0.01)。ICVD组aCL阳性率与CH组比较无显著性差异(P>0.05),ICVD组、CH组和对照组不同性别间aCL阳性率无显著性差异(P>0.05)。结论:aCL可作为CVD危险性增加的指标,对CVD的预测有一定意义,包括ICVD和CH患者,aCL阳性率男女性别之间无差异。  相似文献   
987.
The purpose of this work was to describe the posterior ankle impingement syndrome related to the posterolateral tubercle of the talus bone and to present a retrospective analysis of our results after arthroscopic plasty of the tubercle in 15 ankles with a mean 3-year follow-up. Fifteen cases of posterior ankle impingement (PAI) underwent arthroscopic excision of an impinging bone spur. All the patients (13) were retrospectively evaluated at an average of 36 months after index surgery. There were seven women (bilateral in two of them) and six men. Ten were involved in different kinds of sport and three were professional ballet dancers. Preoperative symptoms included pain localized in the posterior ankle, limitation of motion, weakness and swelling. All patients had failed a course of conservative therapies. Surgery was performed through posterolateral and posteromedial portals as described by van Dijk. After soft tissue debridement, partial resection of the posterolateral process was performed until there was complete plantar flexion without bone impingement. Postoperatively, all patients followed the same rehabilitation protocol. Improvement in their impingement symptoms was recorded in all of them according to AOFAS score. One of them (7%) still had occasional discomfort. The results suggest that arthroscopic bone decompression of the posterolateral tubercle in cases of PAI resistant to non-surgical therapies is an effective treatment.  相似文献   
988.
989.
990.
Microcystic adnexal carcinoma is a rare cutaneous neoplasm characterized by slow but locally aggressive growth, which normally does not lead to systemic metastasis. Frequent local recurrences are reported, which are most likely due to insufficient operative technique. We present the fourth case of cervical ipsilateral metastatic microcystic adnexal carcinoma in an otherwise healthy woman. The patient presented with a previously diagnosed but not completely resected microcystic adnexal carcinoma in the area of the right posterior scalp and two palpable ipsilateral lymph nodes. The tumor was resected using intraoperative snap frozen histological evaluation of the resection borders. In the same procedure two lymph nodes were resected from the right neck. The lymph nodes were histologically assessed and showed infiltration by small strains of tumor cells. After exclusion of a second primary tumor, e.g., mammary carcinoma, as the cause for cervical lymph node metastases, we performed a modified radical neck dissection with resection of the sternocleidomastoid muscle and the accessory nerve, which was histologically proven to be perineurally infiltrated by tumor cells. In this second procedure the histological evaluation of the specimen showed no sign of remaining tumor infiltration. After exclusion of distant metastasis the patient was irradiated with 60 Gy. The patient is well 1 year after the initial treatment without signs of recurrence.  相似文献   
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