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131.
Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT 总被引:1,自引:0,他引:1
Lipton MJ; Farmer DW; Killebrew EJ; Bouchard A; Dean PB; Ringertz HG; Higgins CB 《Radiology》1985,157(3):735-740
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics. 相似文献
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A new needle-wire system has been developed for localization of nonpalpable breast lesions. The curved-end wire, which is made of a tough pseudoelastic alloy, eliminates many of the pitfalls of this procedure for both the radiologist and the surgeon. Advantages of this new system include the ability to anchor the needle during filming, the ability to easily reposition the needle if necessary, the option of injecting dye, the inability to transect the wire during surgery, and the option of leaving both the needle and wire in place in the subject to allow easier dissection during biopsy. 相似文献
134.
Letter: False-positive gram stains of cerebrospinal fluid 总被引:1,自引:0,他引:1
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BACKGROUND: The heat shock response (HSR) attenuates NF-kappaB mediated activation of the acute inflammatory response by inhibiting IkB degradation. The HSR also confers a protective phenotype upon cells through production of heat shock proteins (HSP). However, the exact conditions that induce the HSR and stimulate the production of protective HSP are poorly defined. Consequently, we hypothesized that the inhibition of NF-kappaB activation through the HSR is dependent both on the degree of cellular injury and the length of the recovery period from the heat shock. METHODS: RAW 264.7 murine macrophages were heated to 43 degrees C for 15 (mild heat shock), 45 (moderate heat shock), or 90 min (severe heat shock), allowed to recover at 37 degrees C for 0 to 24 h, and then exposed to 100 ng/ml of Escherichia coli (055:B5) lipopolysaccharide (LPS). Cellular viability, HSP expression, and the activation of NF-kappaB after LPS exposure were determined by alamarBlue assay, immunoblot, and electrophoretic mobility shift assay, respectively. RESULTS: Transient attenuation of NF-kappaB activation and IkappaB preservation was observed only with moderate heat shock and 1 h of recovery. Mild heat shock had no effect on LPS-induced NF-kappaB activation or IkappaB degradation. Severe heat shock completely inhibited NF-kappaB activation and preserved IkappaB protein levels. Heat shock proteins were detectable 30 min after moderate heat shock, with maximal and sustained levels 2 to 24 h after heat shock. CONCLUSION: The attenuation of NF-kappaB activation after heat shock is both dose- and time-dependent. 相似文献
138.
Camp R Feezor R Kasraeian A Cendan J Schell S Wilkinson E Copeland E Lind S 《The breast journal》2005,11(6):394-397
While sentinel lymph node biopsy (SLNB) has virtually replaced axillary dissection as the initial diagnostic procedure for invasive breast cancer, the role of SLNB in ductal carcinoma in situ (DCIS) remains controversial. The purpose of this study was to review our experience with SLNB in DCIS. All patients with DCIS or DCIS with microinvasion (DCISM) who underwent SLNB from June 1997 to April 2002 at the University of Florida were included for analysis. The indications for SLNB were at the discretion of the treating surgeon. Lymphatic mapping involved a sequential dermal-peritumoral radiocolloid injection and dynamic lymphoscintigraphy followed by an intraoperative assessment of radioactivity with a handheld gamma probe. All sentinel lymph nodes (SLNs) with radioactive counts>or=10% of the ex vivo counts of the most radioactive SLN were removed. Pathologic analysis consisted of slicing the SLN at 2 mm intervals for permanent section. All paraffin blocks of the SLNs were step sectioned in 4 microm sections (92 microm spacing) through the entire lymph node. Slides were then stained with an immunohistochemical stain for cytokeratin (AE1/AE3) and evaluated by microscopy. Nodal metastases were classified using the 6th edition of the American Joint Committee on Cancer (AJCC) staging manual. From April 1998 to April 2002, 43 patients with DCIS underwent SLNB at the University of Florida. Seven patients (16%) with multifocal or extensive DCIS (five patients) or DCISM (two patients) who underwent SLNB had a positive sentinel node. Two of the three patients considered positive by immunohistochemistry alone had either DCISM or invasive disease. Four (80%) of the five patients with extensive DCIS and a positive sentinel node were ultimately determined to have invasive or microinvasive disease. While SLNB remains controversial in DCIS, our data suggest that patients with extensive DCIS should undergo SLNB at the initial procedure to avoid the need for a second operation. Data from clinical trials are needed to determine the impact of SLNB results on overall survival in patients with DCIS. 相似文献
139.
Mental health of Cambodian refugees 2 decades after resettlement in the United States 总被引:11,自引:1,他引:10
Context Little is known about the long-term mental health of trauma-exposed refugees years after permanent resettlement in host countries. Objective To assess the prevalence, comorbidity, and correlates of psychiatric disorders in the US Cambodian refugee community. Design, Setting, and Participants A cross-sectional, face-to-face interview conducted in Khmer language on a random sample of households from the Cambodian community in Long Beach, Calif, the largest such community in the United States, between October 2003 and February 2005. A total of 586 adults aged 35 to 75 years who lived in Cambodia during the Khmer Rouge reign and immigrated to the United States prior to 1993 were selected. One eligible individual was randomly sampled from each household, with an overall response rate (eligibility screening and interview) of 87% (n = 490). Main Outcome Measures Exposure to trauma and violence before and after immigration (using the Harvard Trauma Questionnaire and Survey of Exposure to Community Violence); weighted past-year prevalence rates of posttraumatic stress disorder (PTSD) and major depression (using the Composite International Diagnostic Interview version 2.1); and alcohol use disorder (by the Alcohol Use Disorders Identification Test). Results All participants had been exposed to trauma before immigration. Ninety-nine percent (n = 483) experienced near-death due to starvation and 90% (n = 437) had a family member or friend murdered. Seventy percent (n = 338) reported exposure to violence after settlement in the United States. High rates of PTSD (62%, weighted), major depression (51%, weighted), and low rates of alcohol use disorder were found (4%, weighted). PTSD and major depression were highly comorbid in this population (n = 209; 42%, weighted) and each showed a strong dose-response relationship with measures of traumatic exposure. In bivariate analyses, older age, having poor English-speaking proficiency, unemployment, being retired or disabled, and living in poverty were also associated with higher rates of PTSD and major depression. Following multivariate analyses, premigration trauma remained associated with PTSD (odds ratio [OR], 2.08; 95% CI, 1.37-3.16) and major depression (OR, 1.56; 95% CI, 1.24-1.97); postmigration trauma with PTSD (OR, 1.65; 95% CI, 1.21-2.26) and major depression (OR, 1.45; 95% CI, 1.12-1.86); and older age with PTSD (OR, 1.76; 95% CI, 1.46-2.13) and major depression (OR, 1.47; 95% CI, 1.15-1.89). Conclusion More than 2 decades have passed since the end of the Cambodian civil war and the subsequent resettlement of refugees in the United States; however, this population continues to have high rates of psychiatric disorders associated with trauma. 相似文献
140.