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81.
Objective: To study the diagnostic value of T2^*-weighted first-pass perfusion imaging in breast tumors. Methods: We analyzed the magnetic resonance imaging (MRI) information along with the pathological and immunohistochemistry results. Magnetic resonance imaging was performed in 28 patients with breast tumor. The time to signal intensity curves were generated according to the T2^*-weighted first-pass perfusion imaging. The curve's maximal signal intensity drop rate and maximal signal intensity decrease time were analyzed and compared with the pathological diagnoses after surgery. Results: Malignant breast lesions showed higher maximal signal intensity drop rate (44.69% ± 17.07 vs. 17.22% ±7.49, P 〈 0.001) than benign lesions, but there was no significant difference of maximal signal decrease time between those two lesions (23.94 s ± 4.92 vs. 20.02 s ± 6.83, P 〉 0.05). Conclusion: The T2^*-weighted first-pass perfusion imaging has enough sensitivity and specificity in breast tumor diagnosis.  相似文献   
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T-2 toxin is one of the mycotoxins, a group of type A trichothecenes produced by several fungal genera including Fusarium species. In the present study, we have investigated the apoptotic effects of T-2 toxin on chondrocytes and the relationship between T-2 toxin induced chondrocyte apoptosis and its influence on Bcl-2/Bax protein and mRNA expression. We have also examined the inhibitory effects of selenium on chondrocyte apoptosis induced by T-2 toxin. We have combined morphological and biological techniques to establish the relevance of apoptosis in human chondrocyte death induced by T-2 toxin. Treatment with T-2 toxin caused accelerated apoptosis in a concentration dependent manner. The apoptosis induced by T-2 toxin involved an increased Bax/Bcl-2 ratio. Bcl-2 mRNA expression remained unchanged in chondrocyte apoptosis induced by T-2 toxin treatment, while Bax mRNA expression increased following treatment with T-2 toxin. Selenium could partly block the apoptosis of chondrocytes induced by T-2 toxin through decreasing the Bax/Bcl-2 ratio. These results suggest that, under our experimental conditions, apoptosis of chondrocytes can be induced by T-2 toxin (1-20ng/mL) via the Bcl-2 and Bax proteins, and the Bax/Bcl-2 ratio may play a critical role in governing the susceptibility to apoptosis induced by T-2 toxin in human chondrocytes.  相似文献   
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Abstract We report a case of SMV injury in a critically ill patient. The patient was a 19-year-old woman involved in a motor vehicle collision. Her injuries included grade II splenic and renal lacerations, devascularized and lacerated right and transverse colon, a transected transverse mesocolon, a massive shear injury of her abdominal wall, and two partial SMV transections. At initial damage control laparotomy, the SMV was ligated, the devascularized bowel resected and a temporary abdominal closure applied. At re-operation, a mesocaval shunt using saphenous vein was employed. The shunt failed and the patient required a saphenous vein jump graft. Although visceral vascular injuries are rare, ligation of the SMV in a damage control situation is acceptable. This case study is the first to discuss appropriate treatment when interruption to a patient's collateral visceral venous drainage limits the surgeon’s ability to ligate. In these situations, bypass shunts may be successful.  相似文献   
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后循环又称椎基底动脉系统,由椎动脉、基底动脉和大脑后动脉(posterior cerebral artery,PCA)组成,主要向脑干、小脑、丘脑、枕叶、部分颞叶等结构供血。后循环缺血(posterior circulation ischemia,PCI)是常见的缺血性脑血管病。与前循环缺血一样,PCI也可按缺血程度和持续时间的不同分为短暂性脑缺血发作(transient ischemic attack,TIA)和脑梗死。其同义词包括椎基底动脉系统缺血、后循环TIA和脑梗死、椎基底动脉疾病、椎基底动脉血栓栓塞性疾病。  相似文献   
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For persons battling HIV/AIDS a stable place to live may decide the length and quality of life itself. It is nearly impossible for a person on the streets to engage in a needed continuous AIDS treatment regimen when the very basic question of where that person will rest his or her head when darkness comes in just a few hours is unresolved. When danger lurks on the streets, when cold numbs the limbs, when tiredness overwhelms the mind, when fear breaks the spirit, a place to call home would make all the difference.  相似文献   
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OBJECTIVES: This study sought to characterize epileptic phenotypes in children with nonspecific mitochondrial disease (MD) and to evaluate MD diagnostic approaches. METHODS: A retrospective analysis of the medical, electroencephalogram, and laboratory records of 142 patients with epilepsy was performed. The patients were evaluated for MD, and 124 patients were included in the final cohort. The MD criteria used included an oral glucose lactate stimulation test (OGLST) and urine organic acid/plasma amino acid (UOA/PAA) assays as metabolic indicators of modified Walker criteria, as suggested by Bernier et al. (Neurology 59:1406-1411, 2002). RESULTS: Twenty-two patients were classified as having definite MD (9), probable MD (5), possible MD (6), or pyruvate dehydrogenase (PDH) deficiency (3), including one patient which showed a respiratory chain (RC) defect and PDH deficiency. Seven out of eight patients in whom significant RC defects were observed showed complex I defects. In 14 patients, epileptic seizures start at infantile ages. Of 17 patients who substantially presented generalized seizures, 4 patients started with partial seizures. Five patients consistently presented only partial seizures. The OGLST and UOA/PAA assays were useful for a more precise diagnosis of MD, although low positive predictive value of the OGLST was regrettable. No patient was classified as definite MD by Walker's original criteria, but the use of our revised MD criteria resulted in the classification of nine additional patients as definite MD. CONCLUSIONS: MD manifested considerable diverse epileptic phenotypes and should be considered in the differential diagnosis of epilepsy in children with unexplained encephalomyopathy and progressive and fluctuating clinical courses.  相似文献   
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