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101.
猞猁(Lynxlynx)是内蒙古赛罕乌拉国家级自然保护区内的顶级捕食者,在维持该地区生态平衡和调节猎物数量上具有重要地位。分析猞猁粪便样品残留物不仅能明确其猎物构成,了解与同域分布其他捕食者的关系,还能为制定物种保护措施和栖息地管理策略提供科学参考。本研究在2006至2008年间利用样线法在该区域收集到35份猞猁粪便样品。通过相对出现频率法对粪样进行食性分析,发现猞猁的主要食物组成以蒙古兔(Lepus tolai,30.85%)和植物(28.72%)较多;年度(χ~2=18.696,P <0.001)和季节性(χ~2=74.695,P <0.001)食物构成均存在显著差异。结果表明,蒙古兔在猞猁的食物组成中占最重要地位;猞猁的食物构成与季节有关,寒冷季节捕食大型猎物,而温暖季节捕食的小型猎物更常见。  相似文献   
102.
Fan  Fangcheng  Yang  Mengzhu  Geng  Xiwen  Ma  Xiaoli  Sun  Haiji 《Neurochemical research》2019,44(8):1841-1850
Neurochemical Research - Restraint water-immersion stress (RWIS) consists of psychological and physical stimulation, and it has been utilized in the research of gastric mucosal damage. It has been...  相似文献   
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Plant Molecular Biology Reporter - Glycyrrhiza is a widely used traditional Chinese herb with medicinal value. Recently, however, Glycyrrhiza biodiversity has faced an unprecedented threat due to...  相似文献   
105.
A better understanding of breast cancer pathogenesis would contribute to improved diagnosis and therapy and potentially decreased mortality rates. Here, we found that the MORC family CW-type zinc finger 4 (MORC4) overexpression in breast cancer tissues is associated with poor survival, and the short-interfering RNA knockdown of MORC4 suppresses the growth of breast cancer cells by promoting apoptosis. To investigate the mechanisms associated with MORC4 upregulation, microRNAs potentially targeting MORC4 were analyzed, with miR-193b-3p identified as the regulator and a negative correlation between miR-193b-3p and MORC4 expression determined in both breast cancer cell lines and tissues. Further analysis verified that MORC4 silencing did not affect miR-193b-3p expression, although altered miR-193b-3p expression attenuated MORC4 protein levels. Moreover, dual-luciferase reporter assays verified miR-193b-3p binding to the 3′ untranslated region of MORC4. Furthermore, restoration of miR-193b-3p expression in breast cancer cells led to decreased growth and activation of apoptosis, which was consistent with results associated with MORC4 silencing in breast cancer cells. These results identified MORC4 as differentially expressed in breast cancer cells and tissues and its downregulation by miR-193b-3p, as well as its roles in regulating the growth of breast cancer cells via regulation of apoptosis. Our findings offer novel insights into potential mechanisms associated with breast cancer pathogenesis.  相似文献   
106.
KDM6B, also known as JMJD3, is a member of the family of histone lysine demethylase (KDMs), which is closely related to many types of cancers. However, its role and the underlying mechanisms in ovarian cancer remain unknown. Here we show that KDM6B is elevated in epithelial ovarian cancer and its expression level is closely related with metastasis and invasion. In addition, survival analysis showed that high expression of KDM6B was associated with low overall survival in ovarian cancer patients. Overexpression of KDM6B in epithelial ovarian cancer cells promoted proliferation, epithelial-mesenchymal transition (EMT), migration and invasion in vitro, and enhanced metastatic capacities in vivo. On the contrary, silencing KDM6B in invasive and metastatic ovarian cancer cells inhibited these processes. Mechanistically, we found that KDM6B exerts its function by modulating the transforming growth factor-β1 (TGF-β1) expression, and TGF-β1 signal pathway inhibitor LY2157299 significantly inhibited KDM6B-induced proliferation, migration, metastasis, and EMT in ovarian cancer cells. Our findings, for the first time, reveal the pivotal role of KDM6B in the invasion and metastatic behavior of epithelial ovarian cancer. Thus, targeting KDM6B may be a useful strategy to interfere with these behaviors of epithelial ovarian cancer.  相似文献   
107.
Oxidative stress has been implicated in the development of cerebral ischemia/reperfusion (I/R) injury. Glaucocalyxin B (GLB), one of five ent-kauranoid diterpenoids, was reported to possess neuroprotective activity. However, the effect of GLB on oxygen-glucose-deprivation/reperfusion (OGD/R)-induced cell injury in PC-12 cells has not been explored. PC-12 cells was treated with various concentrations of GLB (0, 2.5, 5 and 10 μM), and cell viability was detected using the MTT assay. PC-12 cells were pretreated with the indicated concentration of GLB (2.5-10 μM, 2 hours pretreatment), and were maintained under OGD for 3 hours, followed by 24 hours of reoxygenation. Cell viability was assessed using the MTT assay. The levels of superoxide dismutase, malondialdehyde, and glutathione peroxidase were detected using commercially available ELISA Kits. Intracellular reactive oxygen species level was measured using the fluorescent probe 2′,7′-dichlorofluorescein diacetate. The levels of Bcl-2, Bax, p-Akt, Akt, p-mTOR, mTOR were detected using Western blot. Our results revealed that GLB significantly protected PC12 cells against OGD/R-induced cell injury. In addition, GLB efficiently inhibited oxidative stress and cell apoptosis in OGD/R-stimulated PC-12 cells. Mechanistic studies revealed that pretreatment with GLB could induce the activation of Akt/mTOR signaling pathway resulting in protection of OGD-treated PC12 cells. In conclusion, our data indicate for the first time that GLB protects against OGD/R-induced neuronal injury in PC-12 cells. The mechanism of the protective effect of GLB is partially associated with activation of the Akt/mTOR signaling pathway. Thus, GLB may be a potential agent for protection against cerebral I/R injury.  相似文献   
108.
The inhibitor of growth 4 (ING4) is known as a tumor suppressor. The expressions of ING4 were markedly reduced in human renal clear cell carcinoma (ccRCC) tissues. However, the role of ING4 in renal cell carcinoma (RCC) remains unknown. The aim of the current study was to detect the ING4 expression level and its potential role in human RCC cell lines. Our results showed that ING4 was lowly expressed in human RCC cell lines compared with that in proximal tubular cell line. Ectopic overexpression of ING4 inhibited the proliferation, migration, and invasion properties, and as well as prevented epithelial-mesenchymal transition (EMT) phenotype of RCC cells. In addition, ING4 overexpression induced cell apoptosis and autophagy in RCC cells. Furthermore, ING4 overexpression suppressed the activation of PI3K/Akt pathway in RCC cells. The activator of PI3K/Akt, insulin-like growth factor 1, abolished the effects of ING4 on RCC cells. These findings indicated that ING4 presented anticancer activity in RCC cells. The effects of ING4 on RCC cells were mediated by regulating the PI3K/Akt pathway. These findings suggested that ING4 could be used for gene therapy of RCC.  相似文献   
109.
Accumulating evidence suggested that transient receptor potential melastatin 2–antisense RNA (TRPM2-AS) played crucial roles in the progression of human cancers. However, the role of TRPM2-AS was still unknown in osteosarcoma. The aim of this study was to explore the clinical significance of TRPM2-AS in osteosarcoma patients, and determine the role of TRPM2-AS on osteosarcoma cell proliferation and apoptosis. In our results, we identified a novel oncogenic long noncoding RNA TRPM2-AS, which was overexpressed in osteosarcoma tissues and cells, and correlated with advanced Enneking stage, large tumor size and high histological grade in osteosarcoma cases. Survival analysis indicated that osteosarcoma patients with high TRPM2-AS expression had an obviously shorter overall survival time than those with low TRPM2-AS expression. Loss-of-function studies suggested that suppression of TRPM2-AS expression inhibited osteosarcoma cell proliferation and induced cell apoptosis through upregulating cleaved caspase-3 and cleaved caspase-9 expression. In conclusion, TRPM2-AS acts as an oncogenic long noncoding RNA and predicts poor prognosis in osteosarcoma.  相似文献   
110.
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