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991.
992.
Tse KP Su WH Yang ML Cheng HY Tsang NM Chang KP Hao SP Yao Shugart Y Chang YS 《Human molecular genetics》2011,20(14):2889-2896
Copy number variations (CNVs), a major source of human genetic polymorphism, have been suggested to have an important role in genetic susceptibility to common diseases such as cancer, immune diseases and neurological disorders. Nasopharyngeal carcinoma (NPC) is a multifactorial tumor closely associated with genetic background and with a male preponderance over female (3:1). Previous genome-wide association studies have identified single-nucleotide polymorphisms (SNPs) that are associated with NPC susceptibility. Here, we sought to explore the possible association of CNVs with NPC predisposition. Utilizing genome-wide SNP-based arrays and five CNV-prediction algorithms, we identified eight regions with CNV that were significantly overrepresented in NPC patients compared with healthy controls. These CNVs included six deletions (on chromosomes 3, 6, 7, 8 and 19), and two duplications (on chromosomes 7 and 12). Among them, the CNV located at chromosome 6p21.3, with single-copy deletion of the MICA and HCP5 genes, showed the highest association with NPC. Interestingly, it was more specifically associated with an increased NPC risk among males. This gender-specific association was replicated in an independent case-control sample using a self-established deletion-specific polymerase chain reaction strategy. To the best of our knowledge, this is the first study to explore the role of constitutional CNVs in NPC, using a genome-wide platform. Moreover, we identified eight novel candidate regions with CNV that merit future investigation, and our results suggest that similar to neuroblastoma and prostate cancer, genetic structural variations might contribute to NPC predisposition. 相似文献
993.
Yang J Yang W Hirankarn N Ye DQ Zhang Y Pan HF Mok CC Chan TM Wong RW Mok MY Lee KW Wong SN Leung AM Li XP Avihingsanon Y Rianthavorn P Deekajorndej T Suphapeetiporn K Shotelersuk V Baum L Kwan P Lee TL Ho MH Lee PP Wong WH Zeng S Zhang J Wong CM Ng IO Garcia-Barceló MM Cherny SS Tam PK Sham PC Lau CS Lau YL 《Human molecular genetics》2011,20(3):601-607
994.
995.
996.
Yin J Li X Jing J Li J Mukai D Mahon S Edris A Hoang K Shung KK Brenner M Narula J Zhou Q Chen Z 《Journal of biomedical optics》2011,16(6):060505
We have developed a miniature integrated optical coherence tomography (OCT) ultrasound (US) probing system for intravascular imaging applications. In the OCT probe, the light coming out of a single mode fiber is focused by a gradient-index lens and then reflected by a right-angle prism from the side of the probe into the sample. It was combined with a 35 MHz PMN-PT side-viewing ultrasound transducer to obtain the ultrasound image as well. The OCT and ultrasound probes were integrated as a single probe to obtain OCT and ultrasound images simultaneously. The integrated probe has an outer diameter of 0.69 mm which, to our knowledge, is the smallest integrated OCT-US probe reported. Fast data acquisition and processing was implemented for real-time imaging. In vitro OCT and US images of human coronary artery with pathology, as well as in vivo images of normal rabbit abdominal aorta, were obtained using the integrated OCT-US probe to demonstrate its capability. 相似文献
997.
Wang Liangjie Yang Cindy Lai Hung Or Terry Cho Tsun Chen Gang Zhou Jian Li James Chun Tsun Lau Allan Sik Yin 《Chinese medicine》2011,6(1):1-14
Background
Interstitial pulmonary fibrosis is characterized by an altered cellular composition of the alveolar region with excessive deposition of collagen. Lung inflammation is also common in pulmonary fibrosis. This study aims to test the inhibition of 5-lipooxygenase (5-LOX) by boswellic acid (BA) extract in an experimental model of pulmonary fibrosis using bleomycin (BL).Methods
Boswellic acid extract (1 g/kg) was force-fed to rats seven days prior to administration of BL or gamma irradiation or both. BL (0.15 U/rat) in 25 μl of 0.9% normal saline (NS) or 0.9% NS alone was administered intratracheally. Rats were exposed to two fractionated doses of gamma irradiation (0.5 Gy/dose/week) with a gamma cell-40 (Cesium-137 irradiation units, Canada) during the last two weeks of the experiment. BA was administered during BL or irradiation treatment or both. After the animals were sacrificed, bronchoalveolar lavage was performed; lungs were weighed and processed separately for biochemical and histological studies.Results
In rats treated with BL, levels of transforming growth factor-β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) were significantly elevated (P = 0.05 and P = 0.005). Hydroxyproline was highly and extensively expressed. Immunoreactive compounds were abundantly expressed, represented in the levels of macrophages infiltrate, accumulation of eosinophils and neutrophils in the lung as well as the aggregation of fibroblasts in the fibrotic area. The levels of lipoxygenase enzyme activity were significantly increased (P = 0.005). Antioxidant activities measured in BL-treated rats deteriorated, coupled with the elevation of both levels of plasma lipid peroxide (LP) content and bronchoalveolar lavage lactate dehydrogenase activity. BA-treated rats had reduced number of macrophages, (P = 0.01), neutrophils in bronchoalveolar lavage (P = 0.01) and protein (P = 0.0001). Moreover, the hydroxyproline content was significantly lowered in BA-treated rats (P = 0.005). BA extract inhibited the TGF-ß induced fibrosis (P = 0.01) and 5-LOX activity levels (P = 0.005). Histologically, BA reduced the number of infiltrating cells, ameliorated the destruction of lung architecture and attenuated lung fibrosis.Conclusion
BA attenuates the BL-induced injury response in rats, such as collagen accumulation, airway dysfunction and injury. This study suggests that the blocking of 5-LOX may prevent the progression of fibrosis. 相似文献998.
999.
CD44(+)/CD24(-) cells have been associated with breast cancer stem/progenitor cell features. However, the status of this phenotype cells in normal, benign and malignant breast tissues has not been studied, and the clinical correlation of this subpopulation in breast cancer is not fully understood. The present study sought to identify these cells in a series of normal, benign, and malignant breast tissues and explore their correlation to the molecular subtypes of breast carcinoma and conventional pathological features. Double-staining immunohistochemistry (DIHC) of CD44 and CD24 was performed on 30 normal breast tissues, 30 breast fibroadenomas (FA), 60 breast invasive ductal carcinomas (IDC), and 3 breast cancer cell lines (MCF-7, MDA-MB-468, and MDA-MB-231). In the normal breast tissues and FAs, three phenotypes were observed including CD44(+)/CD24(+), CD44(+)/CD24(-), and CD44(-)/CD24(-) cells. In the IDCs, CD44(-)/CD24(+) cells were detected, in addition to the three aforementioned phenotypes. The strong positive rate (+++, incidence >60%) of CD44(+)/CD24(-) was significantly increased from normal breast tissue, FAs to IDCs (0.0%-->6.7%-->21.7%). However, the CD44(+)/CD24(-) cells didn't correlate with ages of patients, lymph node metastasis, tumor size, molecular subtypes, and the expression of ER, PR, HER-2, PS2, Bcl-2, nm23. The proportion of CD44(+)/CD24(-) cells in MCF-7, MDA-MB-468, and MDA-MB-231 was about 1, 5, and 80%, respectively. The results indicate that the CD44(+)/CD24(-) cells are transit progenitors and have no association with the molecular subtypes and clinicopathological parameters in the IDCs. 相似文献
1000.
尹绍清 《中国健康心理学杂志》2011,19(7):860-861
目的 了解大学生攻击行为的特点及影响因素.方法 采用内容分析法对大学生攻击行为进行调查.结果 大学生攻击行为发生在相互认识的同学间的比例为75.56%,发生在男生与男生之间的比例为62.22%,发生于23时之后的比例为80%;宿舍是大学生攻击行为发生的主要场所,占71.11%;大学生攻击行为主要表现为躯体性攻击和心理性攻击,大学生对攻击行为的应对方式存在较大问题;酗酒是影响大学生攻击行为发生的一个重要因素.结论 攻击行为对大学生生理和心理造成不同程度的伤害,性别、时间、地点及是否酗酒影响大学生攻击行为的发生. 相似文献