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71.
In this study, the fractionation and distribution of phosphorus (P) in the core sediments of the Shanmei reservoir were investigated by using the chemical extraction method in directions for the first time in order to understand its bio-availability, adsorption characteristics, potential release and environmental significance. The results of the study showed that P in the sediments mainly consisted of inorganic phosphorus (IP) and that IP mainly consisted of non-apatite phosphorus (NAIP). The horizontal and temporal distributions of the P fractions were different from each other, but the vertical distribution was similar, which indicated a trend of stabilization after falling. The content of total phosphorus (TP), IP, organic phosphorus (OP), NAIP, apatite phosphorus (AP), and bio-available phosphorus (BAP) in the sediments during the three seasons ranged from 193.85 to 1664.05 mg·kg?1, 126.90 to 1127.70 mg·kg?1, 43.74 to 669.29 mg·kg?1, 57.62 to 937.07 mg·kg?1, 32.58 to 250.71 mg·kg?1, and 41.06 to 871.82 mg·kg?1, respectively. NAIP contents in the sediments accounted for more than 50% of TP. Using an analysis from three aspects, the eutrophication risk index (ERI) could be used to assess the potential release of P in the sediments, and there was a high release risk of P in the sediments in the Shanmei reservoir.  相似文献   
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73.
Haemocyte types of the scallop (Chlamys farreri) were identified by Giemsa stain and flow cytometry (FCM). Additionally, the activities of peroxidase (POD), phenoloxidase (PO) and alkaline phosphatase (ALP) in haemocytes were analysed by immunocytochemical and biochemical methods. The results indicate that there were two types of haemocytes in the scallop, hyalinocytes and granulocytes, and that POD, PO and ALP were more abundant and more active in granulocytes than in hyalinocytes.  相似文献   
74.
目的:观察白介素-6(IL-6)对N-甲基-D-天冬氨酸(NMDA)激发的神经元放电活动的影响及其可能的作用机制。方法:用含IL-6、NMDA和JAK抑制剂ACA90的人工脑脊液(ACSF)灌流小脑脑片,利用离体脑片神经元单位放电细胞外记录技术,记录药物对小脑间位核神经元放电的影响。用Western blot法测定间位核神经元NMDA受体亚单位1(NRI)的磷酸化水平。结果:单独用12.5μmol/L和25μmol/LNMDA灌流,神经元放电频率均较基础放电频率增加;用不同浓度IL-6(50,100,200μg/ml)联合NMDA作用后,神经尤的放电频率出现浓度依赖性地降低;AG490可部分阻断IL-6对NMDA兴奋神经元放电的抑制作用。与单独NMDA处理组比较,用IL-6联合NMDA处理神经元后,神经元的NR1磷酸化水平出现浓度依赖性地降低。AG490可阻断IL-6所致的神经元NR1磷酸化水平的降低。结论:IL-6可抑制NMDA激发的小脑间位核神经元的放电兴奋活动;并同时下调神经元的NR1磷酸化水平。  相似文献   
75.
Oxidative stress plays a critical role in the pathophysiology of cardiac failure, including the modulation of neovascularization following myocardial infarction (MI). Redox molecules thioredoxin (Trx) and glutaredoxin (Grx) superfamilies actively maintain intracellular thiol-redox homeostasis by scavenging reactive oxygen species. Among these two superfamilies, the pro-angiogenic function of Trx-1 has been reported in chronic MI model whereas similar role of Grx-1 remains uncertain. The present study attempts to establish the role of Grx-1 in neovascularization and ventricular remodeling following MI. Wild-type (WT) and Grx-1 transgenic (Grx-1(Tg/+)) mice were randomized into wild-type sham (WTS), Grx-1(Tg/+) Sham (Grx-1(Tg/+)S), WTMI, Grx-1(Tg/+)MI. MI was induced by permanent occlusion of the LAD coronary artery. Sham groups underwent identical time-matched surgical procedures without LAD ligation. Significant increase in arteriolar density was observed 7 days (d) after surgical intervention in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Further, improvement in myocardial functional parameters 30 d after MI was observed including decreased LVIDs, LVIDd, increased ejection fraction and, fractional shortening was also observed in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Moreover, attenuation of oxidative stress and apoptotic cardiomyocytes was observed in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Increased expression of p-Akt, VEGF, Ang-1, Bcl-2, survivin and DNA binding activity of NF-κB were observed in the Grx-1(Tg/+)MI group when compared to WTMI animals as revealed by Western blot analysis and Gel-shift analysis, respectively. These results are the first to demonstrate that Grx-1 induces angiogenesis and diminishes ventricular remodeling apparently through neovascularization mediated by Akt, VEGF, Ang-1 and NF-κB as well as Bcl-2 and survivin-mediated anti-apoptotic pathway in the infarcted myocardium.  相似文献   
76.

Background

This study compared the performance of endoscopic ultrasonography (EUS) and multislice spiral computed tomography (MSCT) in the preoperative staging of gastric cancer.

Methodology/Principal Findings

A total of 610 patients participated in this study, all of whom had undergone surgical resection, had confirmed gastric cancer and were evaluated with EUS and MSCT. Tumor staging was evaluated using the Tumor-Node-Metastasis (TNM) staging and Japanese classification. The results from the imaging modalities were compared with the postoperative histopathological outcomes. The overall accuracies of EUS and MSCT for the T staging category were 76.7% and 78.2% (P=0.537), respectively. Stratified analysis revealed that the accuracy of EUS for T1 and T2 staging was significantly higher than that of MSCT (P<0.001 for both) and that the accuracy of MSCT in T3 and T4 staging was significantly higher than that of EUS (P<0.001 and 0.037, respectively). The overall accuracy of MSCT was 67.2% when using the 13th edition Japanese classification, and this percentage was significantly higher than the accuracy of EUS (49.3%) and MSCT (44.6%) when using the 6th edition UICC classification (P<0.001 for both values).

Conclusions/Significance

Our results demonstrated that the overall accuracies of EUS and MSCT for preoperative staging were not significantly different. We suggest that a combination of EUS and MSCT is required for preoperative evaluation of TNM staging.  相似文献   
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78.
Postconditioning has regenerated interest as a mechanical intervention against cerebral ischemia/reperfusion injury, but its molecular mechanisms remain unknown. We previously reported that hypoxic postconditioning (HPC) ameliorated neuronal death induced by transient global cerebral ischemia (tGCI) in hippocampal CA1 subregion of adult rats. This study tested the hypothesis that p38-mitogen-activated protein kinase (p38 MAPK)/mitogen- and stress-response kinase 1 (MSK1) signaling pathway plays a role in the HPC-induced neuroprotection. Male Wistar rats were subjected to 10 min ischemia induced by applying the four-vessel occlusion method. HPC with 120 min was applied at 24 h after reperfusion. Immunohistochemistry and Western blot were used to detect the expression of phosphorylation of p38 MAPK and MSK1, as well as cleaved caspase-3. We found that HPC induced a significant increase of phosphorylated p38 MAPK and MSK1 in neurons of hippocampal CA1 region and a significant decrease in glial cells after tGCI as well. Furthermore, HPC attenuated caspase-3 cleavation triggered by tGCI in CA1 region. Moreover, p38 MAPK inhibition by SB203580 significantly decreased the phosphorylation of MSK1, increased cleaved caspase-3 expression, and abolished the neuroprotection of HPC. These findings suggested that p38 MAPK/MSK1 signaling axis contributed to HPC-mediated neuroprotection against tGCI, at least in part, by regulating the activation of caspase-3.  相似文献   
79.
记述了中国台湾蹦蝗属Sinopodisma Chang, 1940 3个新种。新种黄氏蹦蝗Sinopodisma huangi sp. nov. 同素木蹦蝗S. shirakii (Tinkham, 1936) 近似,但前胸背板的眼后带下缘具长方形黑斑和体较大,体长雄性为21.3~21.8 mm,雌性29.3 mm。 新种徐氏蹦蝗Sinopodisma xui sp. nov. 近似黄氏蹦蝗Sinopodisma huangisp. nov.,不同之处为前胸背板沿中隆线缺黑色纵带纹,后缘中央具浅的凹陷,前胸背板黑色眼后带下方具倾斜纹, 腹板中隔长等于最狭处。新种杨氏蹦蝗Sinopodisma yangi sp. nov. 近似台湾蹦蝗formosana (Shiraki, 1910),不同之处为体较细,黑色眼后带在前胸背板下缘具长方形突出带,向后到达腹部未端,腹板中隔长为最狭处的1.2 倍。列出了产于台湾的蹦蝗属8个种的检索表。  相似文献   
80.
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