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991.
Paraneoplastic thrombocytosis has been reported in different types of solid tumors, including ovarian epithelial cancer, and found to be associated with a worse outcome. Although the effect of cancer on increasing platelet counts is well documented, the effect of cancer on platelet functions is not well known. We compared in vitro aggregation response of platelets isolated from 34 patients with ovarian cancer to those of platelets from 19 patients with benign ovarian tumors. Aggregation studies were conducted in a light transmission aggregometer, using both a high and a low dose of ADP and collagen. We evaluated platelet preactivation by measuring the plasma concentration of β-thromboglobulin (β-TG) and platelet factor-4 (PF-4) as markers of platelet α granule secretion, using ELISA. We found that ovarian cancer is not associated with an enhanced aggregation response of platelets to ADP or collagen, and plasma concentration of β-TG and PF-4 is not higher in patients with ovarian cancer compared to those in patients with benign ovarian tumors.  相似文献   
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Left coronary artery compression syndrome is an uncommon entity and characterized by compression of the LMCA in-between the aorta and an enlarged main pulmonary arterial trunk. It is usually associated with a congenital cardiac defect. Cardiac 64-slice MDCT provides a non-invasive and an accurate method for assessing the degree of dynamic LMCA compression throughout the cardiac cycle, its angulation relative to the left sinus of Valsalva and depiction of pulmonary pathology, making it a valuable tool in the workup of patients suspected of left coronary artery compression.  相似文献   
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Cell-type-specific signatures of microRNAs on target mRNA expression   总被引:11,自引:0,他引:11       下载免费PDF全文
Although it is known that the human genome contains hundreds of microRNA (miRNA) genes and that each miRNA can regulate a large number of mRNA targets, the overall effect of miRNAs on mRNA tissue profiles has not been systematically elucidated. Here, we show that predicted human mRNA targets of several highly tissue-specific miRNAs are typically expressed in the same tissue as the miRNA but at significantly lower levels than in tissues where the miRNA is not present. Conversely, highly expressed genes are often enriched in mRNAs that do not have the recognition motifs for the miRNAs expressed in these tissues. Together, our data support the hypothesis that miRNA expression broadly contributes to tissue specificity of mRNA expression in many human tissues. Based on these insights, we apply a computational tool to directly correlate 3' UTR motifs with changes in mRNA levels upon miRNA overexpression or knockdown. We show that this tool can identify functionally important 3' UTR motifs without cross-species comparison.  相似文献   
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OBJECTIVE: To analyze the clinical behavior of patients with stage II-IV low-grade serous carcinoma of the ovary seen at our institution who underwent primary surgery followed by platinum-based chemotherapy. METHODS: Patients with stage II-IV low-grade serous carcinoma of the ovary from 1978 to 2003 were identified using existing databases. Clinicopathologic information was obtained from medical records. Progression-free survival and overall survival were estimated by the method of Kaplan and Meier. The log-rank test was used to compare differences between survival curves. Univariable and multivariable analyses were performed using Cox proportional hazards regression. RESULTS: We identified 112 eligible patients. Median age was 43 years.; 90% had stage III disease. Preoperative serum CA 125 was elevated in 86% of patients. The most common sites of extraovarian disease were omentum, fallopian tubes, pelvic peritoneum, and uterus. Response rate to platinum-based chemotherapy in 10 evaluable patients (15% of patients with gross residual disease) was 80%, and 42 patients underwent second-look surgery: microscopically negative findings, 2 (5%); microscopically positive disease, 13 (33%); macroscopically positive disease, 24 (62%); and insufficient information, 3 (7%). Median progression-free survival and overall survival times were 19.5 and 81.8 months. Persistent disease after primary chemotherapy was the only factor associated with shorter overall survival time (hazard ratio 3.46, 95% confidence interval 2.00-5.97, P<.001). CONCLUSION: Metastatic low-grade serous carcinoma of the ovary is characterized by young age at diagnosis and prolonged overall survival. Segregating women with this diagnosis in future clinical trials is warranted.  相似文献   
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Stroke is an increasingly prevalent clinical condition and second leading cause of death globally. The present study evaluated the therapeutic potential of Indian Ginseng, also known as Withania somnifera (WS), supplementation on middle cerebral artery occlusion (MCAO) induced mitochondrial dysfunctions in experimental model of ischemic stroke. Stroke was induced in animals by occluding the middle cerebral artery, followed by reperfusion injury. Ischemia reperfusion injury resulted in increased oxidative stress indicated by increased reactive oxygen species and protein carbonyl levels; compromised antioxidant system; in terms of reduced superoxide dismutase and catalase activity, along with reduction in GSH levels and the redox ratio, impaired mitochondrial functions and enhanced expression of apoptosis markers. Ischemia reperfusion injury induced mitochondrial dysfunctions in terms of (i) reduced activity of the mitochondrial respiratory chain enzymes, (ii) reduced histochemical staining of complex-II and IV, (iii) reduced in-gel activity of mitochondrial complex-I to V, (iv) mitochondrial structural changes in terms of increased mitochondrial swelling, reduced mitochondrial membrane potential and ultrastructural changes. Additionally, an increase in the activity of caspase-3 and caspase-9 was also observed, along with altered expression of apoptotic proteins Bcl-2 and Bax in MCAO animals. MCAO animals also showed significant impairment in cognitive functions assessed using Y maze test. WS pre-supplementation, on the other hand ameliorated MCAO induced oxidative stress, mitochondrial dysfunctions, apoptosis and cognitive impairments. The results show protective effect of WS pre-supplementation in ischemic stroke and are suggestive of its potential application in stroke management.

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