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281.
Exercise cross-sectional echocardiography in ischemic heart disease.   总被引:3,自引:0,他引:3  
We performed cross-sectional echocardiograms at rest, during supine bicycle exercise, and after sublingual nitroglycerin administration in 28 patients suspected of having ischemic heart disease. Technically adequate exercise cross-sectional echocardiograms were obtained in 20 patients (71%). Ten patients had new areas of reversible segmental dysynergy, and all 10 had significant stenoses of coronary arteries supplying areas of the heart corresponding to the location of reversible dysynergy. Six of these 10 patients also underwent exercise thallium-201 perfusion scanning, and all six had reversible perfusion defects in the area that demonstrated reversible dysynergy on exercise cross-sectional echocardiography. At least two of the remaining 10 patients who did not have reversible segmental dysynergy on exercise cross-sectional echocardiography probably experienced myocardial ischemia that we did not detect. We conclude that exercise cross-sectional echocardiography is technically difficult but feasible. The mechanical consequences of exercise-induced regional myocardial ischemia can be detected noninvasively by real-time, two-dimensional, cross-sectional echocardiography.  相似文献   
282.
The opportunistic pathogens, Acanthamoeba and Balamuthia, are the causative agents of the fatal central nervous system (CNS) infection granulomatous amoebic encephalitis. We report an infection of Acanthamoeba in an HIV+ individual. In the present case, multiple lesions were observed in the skin, brain, lung, liver, and bone. A polymerase chain reaction (PCR) assay specific for Acanthamoeba was positive on tissue from a brain biopsy that had been embedded in paraffin. This report demonstrates the need for the consideration of Acanthamoeba infections in HIV+ individuals with skin lesions and multiple lesions throughout the body with CNS involvement. The results of the present study demonstrate that opportunistic amoebic infections can be diagnosed by PCR from paraffin-embedded biopsy material.  相似文献   
283.
OBJECTIVES/HYPOTHESIS: Detection of complications after mandibular fracture repair is generally based on the clinical examination. However, postoperative evaluation of the patient often includes imaging of the repaired mandible. At our institution, the majority of patients with mandibular fracture have had at least one panoramic mandible radiograph taken postoperatively. The purpose of this study was to assess whether these radiographic studies contributed to detection of complications and thereby had an impact on the clinical course of the patient. STUDY DESIGN: Retrospective review. METHODS: The available medical records over a 5-and-a-half-year period of all patients who were treated at our institution for a fractured mandible were reviewed. Patients included in the study were those who were followed for at least 2 months and two postoperative visits. RESULTS: Our series of 289 patients included 25 patients with complications. Of these patients, 24 had postoperative panoramic radiographs. All of the complications were discovered based on history and physical examination. In six of the patients with complications, the panoramic radiograph was suspicious for a complication. There were five false-positive studies of the 240 postoperative studies performed in patients without complications. No complications were diagnosed based on radiography. CONCLUSIONS: After surgical treatment of mandibular fractures, panoramic radiographs add little to the physical examination and history toward the detection of complications. We believe that panoramic radiographs need not be used routinely, but may be reserved for patients who have complaints or physical findings suggestive of complications.  相似文献   
284.
Wang Z  Childress AR  Wang J  Detre JA 《NeuroImage》2007,36(4):1139-1151
To explore the multivariate nature of fMRI data and to consider the inter-subject brain response discrepancies, a multivariate and brain response model-free method is fundamentally required. Two such methods are presented in this paper by integrating a machine learning algorithm, the support vector machine (SVM), and the random effect model. Without any brain response modeling, SVM was used to extract a whole brain spatial discriminance map (SDM), representing the brain response difference between the contrasted experimental conditions. Population inference was then obtained through the random effect analysis (RFX) or permutation testing (PMU) on the individual subjects' SDMs. Applied to arterial spin labeling (ASL) perfusion fMRI data, SDM RFX yielded lower false-positive rates in the null hypothesis test and higher detection sensitivity for synthetic activations with varying cluster size and activation strengths, compared to the univariate general linear model (GLM)-based RFX. For a sensory-motor ASL fMRI study, both SDM RFX and SDM PMU yielded similar activation patterns to GLM RFX and GLM PMU, respectively, but with higher t values and cluster extensions at the same significance level. Capitalizing on the absence of temporal noise correlation in ASL data, this study also incorporated PMU in the individual-level GLM and SVM analyses accompanied by group-level analysis through RFX or group-level PMU. Providing inferences on the probability of being activated or deactivated at each voxel, these individual-level PMU-based group analysis methods can be used to threshold the analysis results of GLM RFX, SDM RFX or SDM PMU.  相似文献   
285.
建立参附注射液中5种重金属及有害元素(铅、镉、砷、汞、铜)的测定方法。样品经微波消解,采用石墨炉原子吸收法测定铅、镉、铜;采用原子荧光法测定砷、汞。5种重金属及有害元素的回收率为94.8%~111.5%。该方法简便、准确、可较好的用于参附注射液中重金属及有害元素的测定。  相似文献   
286.
A field test was performed in El Salvador to evaluate the usefulness of the Shape&Roll prosthetic foot, a foot developed for low-income countries, involving 12 participants. Quantitative gait parameters were measured with a Direct Ultrasound Ranging System (DURS). Qualitative information was obtained from questionnaires administered before and after a three-week trial. The results indicate that the Shape&Roll foot widened the speed range of all participants. According to the questionnaires, the Shape&Roll foot eases walking, enabling participants to walk significantly longer distances. The participants rated its roll-over as very natural and smooth, resulting in a self-perceived reduced walking effort. Handling inclined and uneven surfaces was also rated superior to their current Solid Ankle Cushioned Heel (SACH)-like feet.  相似文献   
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