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51.
对国人颅骨径的测量已不少见,但多为依据骨骼人类学性别特征进行性别鉴定、或未经性别鉴定的材料,而对已知生前性别者的测量并不甚多,为了积累国人体质材料,并为人类学、解剖学及法医学等研究提供参考依据,我们按《人体骨骼测量方法》(吴汝康等,1965)和《人体测量手册》(邵象清,1985)等所列标准为主要依据,对青岛出土、已知性别(据墓碑记载)、多为汉族、较完整的312例(男154,女158)成人颅骨进行了十四项径的直线测量,对所测数据进行了统计学处理和性别差异检验。现将主要结果列于上页表。  相似文献   
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张掖东大山地区的植被   总被引:2,自引:0,他引:2       下载免费PDF全文
东大山位于甘肃省河西走廊张掖县的东北部,为龙首山山脉的一个组成部分,是龙首山的西段,最高峰海拔3600多米,山地南坡和北坡山脚均与辽阔的戈壁滩相接,海拔高度北坡山脚大致为2000米,南坡山脚大致为1800米。降水量因山地不同、海拔高度不同而相差很大,海拔2200米以下年降水量只有150—190毫米,而海拔2400—3600米处则可达到300—400毫米以上。  相似文献   
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浙江金衢盆地小麦—杂草群落的研究   总被引:9,自引:1,他引:8  
用模糊图论中的最大树法,对金衢盆地的小麦-杂草群落进行了分类研究,结果表明,该区小麦-杂草群落分成4个类型,即潮土田上的小麦(Triticum aestivum)-野燕麦(Auena fatua)-春蓼(Polygonum persicaria)一荠菜(Caspsella bura-pas-toria)-猪殃殃(Galium aparine var.teneruml)群落,低丘岗地上的小麦-猪殃殃-野燕麦-波斯婆婆纳(Veronica persica)群落,水稻土田上的小麦-看麦娘(Alopecurusaequalis)-雀舌草(Stellaria alsine)-牛繁缕(Malachium aquaticum)-春蓼群落及烂浸田上的小麦-翅茎灯心草(Juncus alatus)-春蓼-看麦娘-扬子毛茛(Ranunculus sieboldii)群落。分析表明,土壤类型、pH、地形地貌、耕作制度、栽培措施是影响该区小麦-杂草群落结构及分布的主要因素。  相似文献   
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For the first time, a 3D Prussian blue analogue (PBA) with well‐defined spatial organization is fabricated by using a nickel hydroxide array as a precursor. The nickel hydroxide arrays are synthesized in titanium foil and reacted with K3[Fe(CN)6]. The plate‐like morphology of the nickel hydroxide is perfectly preserved and combined with abundant PBA nanocubes. After phosphidation at 350 °C, the obtained sample demonstrated excellent hydrogen evolution reaction (HER) activity in both acid and alkaline solutions to reach a current density of 10 mA cm?2 with an overpotential of only 70 and 121 mV, respectively. With an overpotential of 266 mV, it can reach a larger current density of 500 mA cm?2 in acid. The efficient HER activity of the obtained sample is mainly ascribed to its structural advantage with various active metal sites derived from the nickel hydroxide and PBA precursor. In addition, long‐term stability measurements have verified the good performance of the obtained sample in acid and alkaline solutions. An increment of overpotential of only 8 and 9 mV is observed, in the acid and alkaline solutions respectively. Beyond these assets, it is supposed that the strategy to synthesize 3D PBA arrays from nickel hydroxide can be extended to other metal–organic frameworks arrays for more electrochemical applications.  相似文献   
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Hydrogen peroxide (H(2)O(2)), a representative ROS, has been used to study the apoptosis of cancer cells to oxidative stress. In this study, we exploited the cellular and molecular mechanisms involved in H(2)O(2)-induced apoptosis in human gastric carcinoma MGC803 cells. Exposure of cells to H(2)O(2) might cause significant viability loss and the increase in apoptotic rate. Treatment with 0.4 mmol/L H(2)O(2) up-regulated Bax but down-regulated Bcl-2 in a time-dependent manner, while Bcl-xL expression remained unchanged. Our results also showed that the levels of Fas and Fas-L were increased, the pro-caspase-3 and pro-caspase-9 were down-regulated in H(2)O(2)-treated MGC803 cells. Under H(2)O(2) stress, we found that the protein p53 also participated in MGC803 cells apoptosis. Taken together, the present study indicated that Fas-mediated cell surface death receptor pathway and mitochondria-mediated pathway may participate in regulating the MGC803 cells apoptosis under oxidative stress.  相似文献   
57.
Curcumin, an active ingredient from the rhizome of the plant, Curcuma longa, has antioxidant, anti-inflammatory and anti-cancer activities. It has recently been demonstrated that the chemopreventive activities of curcumin might be due to its ability to inhibit cell growth and induce apoptosis. In the present study, we have investigated the effects of curcumin on growth and apoptosis in the human ovarian cancer cell line Ho-8910 by MTT assay, fluorescence microscopy, flow cytometry and Western blotting. Our data revealed that curcumin could significantly inhibit the growth and induce apoptosis in Ho-8910 cells. A decrease in expression of Bcl-2, Bcl-X(L) and pro-caspase-3 was observed after exposure to 40 microM curcumin, while the levels of p53 and Bax were increased in the curcumin-treated cells. These activities may contribute to the anticarcinogenic action of curcumin.  相似文献   
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To assess the potential zoonotic transmission of giardiasis from dogs in China, a total of 205 fecal specimens from dogs were screened for Giardia duodenalis using PCR and sequence analysis of the triosephosphate isomerase gene. The prevalence of G. duodenalis in dogs was 13.2% (27/205). The potentially zoonotic assemblage A and the dog-specific assemblage C was identified in 25 (12.2%) and two (1.0%) dogs, respectively. All assemblage A isolates belonged to sub-assemblage AI, genotype AI-1. Likewise, one subtype was found in assemblage C. The high occurrence of potentially zoonotic G. duodenalis subtype AI-1 in dogs that are in close contact with humans is of public health concern.  相似文献   
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