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1.
Metabolic Brain Disease - Bupleurum chinense DC. (Chaihu) is a traditional Chinese medicine (TCM) used in the treatment of anxiety. But the anxiolytic mechanisms of bupleurum are still unclear.... 相似文献
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A Well-Balanced Positivity-Preserving Quasi-Lagrange Moving Mesh DG Method for the Shallow Water Equations
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A high-order, well-balanced, positivity-preserving quasi-Lagrange moving
mesh DG method is presented for the shallow water equations with non-flat bottom
topography. The well-balance property is crucial to the ability of a scheme to simulate perturbation waves over the lake-at-rest steady state such as waves on a lake or
tsunami waves in the deep ocean. The method combines a quasi-Lagrange moving
mesh DG method, a hydrostatic reconstruction technique, and a change of unknown
variables. The strategies in the use of slope limiting, positivity-preservation limiting,
and change of variables to ensure the well-balance and positivity-preserving properties are discussed. Compared to rezoning-type methods, the current method treats
mesh movement continuously in time and has the advantages that it does not need to
interpolate flow variables from the old mesh to the new one and places no constraint
for the choice of a update scheme for the bottom topography on the new mesh. A selection of one- and two-dimensional examples are presented to demonstrate the well-balance property, positivity preservation, and high-order accuracy of the method and
its ability to adapt the mesh according to features in the flow and bottom topography. 相似文献
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Melatonin induces apoptosis of colorectal cancer cells through HDAC4 nuclear import mediated by CaMKII inactivation
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Melatonin induces apoptosis in many different cancer cell lines, including colorectal cancer. However, the precise mechanisms involved remain largely unresolved. In this study, we provide evidence to reveal a new mechanism by which melatonin induces apoptosis of colorectal cancer LoVo cells. Melatonin at pharmacological concentrations significantly suppressed cell proliferation and induced apoptosis in a dose‐dependent manner. The observed apoptosis was accompanied by the melatonin‐induced dephosphorylation and nuclear import of histone deacetylase 4 (HDAC4). Pretreatment with a HDAC4‐specific siRNA effectively attenuated the melatonin‐induced apoptosis, indicating that nuclear localization of HDAC4 is required for melatonin‐induced apoptosis. Moreover, constitutively active Ca2+/calmodulin‐dependent protein kinase II alpha (CaMKIIα) abrogated the melatonin‐induced HDAC4 nuclear import and apoptosis of LoVo cells. Furthermore, melatonin decreased H3 acetylation on bcl‐2 promoter, leading to a reduction of bcl‐2 expression, whereas constitutively active CaMKIIα(T286D) or HDAC4‐specific siRNA abrogated the effect of melatonin. In conclusion, the present study provides evidence that melatonin‐induced apoptosis in colorectal cancer LoVo cells largely depends on the nuclear import of HDAC4 and subsequent H3 deacetylation via the inactivation of CaMKIIα. 相似文献
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人体蠕形螨的生物学研究 总被引:4,自引:0,他引:4
用透明胶带法观察蠕形螨在人体面部的寄生、逸出及其在体外的存活能力。结果表明:毛囊蠕形螨(Demod-exfoliculorum,D.f.)主要以颚体朝向毛囊底部寄生,且常常有多条群居现象,而皮脂蠕形螨,(Demodexbrevis,D.b.)一般为单条独居生活。两种人体蠕形螨昼夜均可主动爬出毛囊口出现在皮肤表面,D.f.以白天1000~1800为逸出高峰;D.b.则以夜间2200~200逸出最多。此外,蠕形螨在体外有较强的活动力和存活力。透明胶带法在人体蠕形螨的流行病学调查和生物学研究方面具有较高的应用价值 相似文献
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赤芍总苷对沙土鼠全脑缺血再灌注损伤的保护作用 总被引:3,自引:0,他引:3
OBJECTIVE: To study the protective effects of the total paeony glycoside (TPG) against global cerebral ischemia-reperfusion injury in gerbils. METHODS: Gerbils models of global cerebral ischemia-reperfusion injury were prepared by bilateral common carotid artery ligation for 12 min followed by 24-hour reperfusion. The effects of TGP on brain edema index, superoxide dismatase (SOD) activity and malonaldehyde (MDA) concentration of the cerebral tissue homogenate and pathology of the brain were examined 24 h after model establishment. RESULTS: Compared with the model group, TPG at the doses of 200 and 400 mg/kg could significantly relieve brain edema, enhance SOD activity and lower MDA concentration in the gerbils. Pathological examination showed that the gerbils with TPG treatment had milder injury of the cells in the hippocampal CA1 region. CONCLUSIONS: TPG has obvious protective effects against global cerebral ischemia-reperfusion injury. 相似文献
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外伤性延迟性脾破裂的诊断和治疗(附21例报告) 总被引:1,自引:0,他引:1
目的探讨外伤性延迟性脾破裂的发病规律、临床特点、诊断和治疗方法。方法结合国内外资料及本组病例进行回顾性分析。结果明确诊断16例,误诊为肝破裂2例,宫外孕破裂2例,脾肿瘤1例。21例均手术治疗,行脾切除14例,其中保留副脾2例;脾切除加自体脾组织网膜内移植术3例;脾缝合修补术3例;脾部分切除术1例。死亡1例,原因有就诊晚、失血性休克。结论本病由于腹腔内出血与受伤时间间隔长,容易误诊。诊断除依靠病史、临床表现外,应及时进行腹腔穿刺、B超及CT检查。治疗以脾切除为主,可根据病情、脾破裂的程度以及是否有合并伤等情况采取保脾手术。 相似文献