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Search Results: 1 - 10 of 158379 matches for " 黄庆国 "
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取代芳烃化合物对水生生物的急性毒性与其分子轨道能级的定量关系

科学通报 , 1995,
Abstract: 定量结构-活性相关(QSARs)常被用来研究同系列有机化合物的某些生物毒性与其分子结构之间的定量相关关系.成熟的QSAR方程可以用来预测未知活性化合物的生物活性,这对于有毒化合物的初步筛选,降低毒性评价工作的昂贵费用都有着重要的意义.本文以“受体学说”和“线性自由能相关理论”为基础,将有机污染物的前线分子轨道能作为一种参数引入QSAR方法,研究了卤代苯、苯胺、苯酚等取代芳烃化合物对水生生物的急性毒性与其理化参数的定量关系.
永冻覆岩层下综采工作面坚硬顶板弱化处理技术
,肖洪天,赵军
煤炭科学技术 , 2015,
Abstract: 针对卡洼掌煤矿工作面上覆岩层为永冻岩层,为了保证在该条件下坚硬顶板综采工作面安全生产,在开切眼内向顶板钻孔进行工作面断顶爆破,同时在工作面运输巷和回风巷向顶板布置扇形钻孔进行拉槽截断爆破,在永冻覆岩层下实施了工作面顶板爆破预裂弱化试验,并通过综采工作面安装的KJ27在线监测系统,对顶板弱化处理后的采场矿山压力显现进行监测。监测结果表明:采场顶板初次来压和周期来压步距分别为19、15m,周期来压步距较顶板弱化前降低50%,避免了工作面大面积悬顶的威胁,防止工作面顶板事故的发生。
羧甲基-β-环糊精的合成及对卤代芳烃的增溶研究
高士祥,王连生,
环境化学 , 2015,
Abstract: 本文报道了羧甲基-β-环糊精的一种简便合成方法,并研究了羧甲基-β-环糊精对卤代芳烃类化合物的增溶作用.羧甲基-β-环糊精能与水以任意比例互溶,其水溶液对卤代芳烃有明显的增溶作用.增溶作用的大小主要与卤代芳烃的疏水性及分子的几何形状与环糊精空腔的匹配程度有关.
环糊精对多环芳烃的增溶作用
高士祥,王连生,
环境化学 , 2015,
Abstract: 本文研究了β-环糊精(β-CD)对六种PAH的增溶作用,β-CD的存在使PAH在水中的溶解度显著增加.增溶作用主要是由于PAH与β-CD形成包合物而引起的,增溶作用的大小与包合物分子的大小和lgKow有关.分子结构与β-CD空腔匹配程度好,lgKow大的化合物,增溶作用强.
美国图书馆与信息科学学院信息科学专业本科课程设置的典型分析与启示
,
图书情报工作 , 2009,
Abstract: ?概述美国图书情报学专业课程设置的研究情况,重点选取5所居于2006年美国top10图书馆与信息科学学院信息科学专业,以其本科课程设置情况为研究对象,从专业必修课、专业选修课、专业预修课程和公共选修课等角度进行比较分析,概括了其课程设置的4大特色;并探讨了这些特色对于我国图书情报教育的启示。
胃空肠储袋侧-端吻合术(附66例报告)
Gastric Jejunum-Pouch Side-End Anastomosis : 66 Case Reports
 [PDF]

曹永宽, 干伟, 周均, 龚加, 王培红,, ,, 宋亚宁
Hans Journal of Surgery (HJS) , 2014, DOI: 10.12677/HJS.2014.34012
Abstract:
目的:介绍一种胃空肠吻合的新术式——胃空肠储袋侧-端吻合术。方法:在传统Billroth II式胃空肠吻合术基础上,成都军区总医院胃肠外科设计了在输入袢与输出袢交汇处增加空肠侧-侧吻合形成空肠储袋,其顶端与胃后壁吻合的新术式——胃空肠储袋侧-端吻合术。本文回顾性分析自2012年3月至2014年2月实施66例胃空肠储袋侧-端吻合术患者的临床资料。其中,51例实施手辅助腹腔镜远端胃癌D2根治术,8例不能切除胃癌行上腹部正中小探查切口、胃空肠储袋侧-端吻合术+小弯侧血管神经结扎切断术,7例良性幽门梗阻行手辅助腹腔镜高选择性迷走神经切断+远端半胃切除术。结果:手术切口6.5~8 cm(平均7.1 cm),手术时间70~205 min(平均165.6 min),术中出血量50~300 ml(平均174.5 ml),肛门排气时间2~5天(平均3.7天),术后饮食恢复时间3~7天(平均4.6天),术后住院时间6~13天(8.3天)。术后2 h腹腔血管出血1例,再手术止血治愈。无胃瘫,无围手术期死亡。随访1~12个月,患者自述无反酸和反流性食管炎症状出现,胃镜复查见轻度吻合口炎3例,胃内胆汁返流明显者2例。结论:胃空肠储袋侧-端吻合术,操作简单,手术安全,且预防反流性胃炎的临床效果良好;空肠储袋具有贮存和收集胆汁等消化液的功能,有利于患者术后早期恢复。
Objectives: To introduce a simple new operation of gastrojejunostomy, gastric jejunum-pouch side-end anastomosis was to be reported. Method: Gastric jejunum-pouch side-end anastomosis, which was designed by the gastrointestinal ward of the Chengdu Army General Hospital, was jejunal pouch with the stomach wall anastomosis, such as Billroth II gastrojejunostomy. The clinical data of 66 cases of gastric jejunum-pouch anastomosis were analyzed retrospectively from March 2012 to February 2014. Among them, 51 cases are hand assisted laparoscopic D2 radical distal gastrectmy; 8 cases on small and medium-sized probe incision and gastric jejunum-pouch anastomosis, plus the little side vascular nerve ligation amputation; 7 cases on laparoscopic highly selective vagus nerve cut plus distal gastrectomy. Results: Incision length 6.5 - 8 cm (7.1 cm on average), operation time 70 - 205 min (mean 165.6 min), intraoperative blood loss 50 - 300 ml (174.5 ml), anal exhaust time 2 - 5 days (mean 3.7 days), postoperative diet recovery time 3 - 7 days (mean 4.6 days), postoperative hospital stay 6 - 13 days (mean 8.3 days). Abdominal vascular hemorrhage after 2 h in 1 case was cured by surgical hemostasis. In all 66 cases, there was no gastric parplysis, and no perioperative death. During 1 - 12 months after operation, no reflux and reflux esophageal inflammation shape were complained of by patients, but the light anastomotic inflammation in 3 cases and gastric bile reflux significantly in 2 cases were checked out by gastroscope review. Conclusions: Gastric jejunum-pouch side-end anastomosis was a simple and safe operation; and the clinical effect to prevent reflux gastritis was good. Jejunum-pouch to be of the function of storage and collection of the digestive juice, such as bile and ect., might be beneficial to patients for early postoperative recovery.

疼痛表情对秒下及秒上时距知觉的影响
顺航,刘培朵,,陈有,希庭
- , 2018,
Abstract: 摘要: 采用二分法和泛化法范式,在秒下及秒上呈现时距探究疼痛表情对时距知觉的影响。结果发现,使用二分法,疼痛表情在秒上秒下都显著延长了个体的主观时距,但使用泛化法,疼痛表情仅在秒上产生影响。根据时间分段综合模型和范式特点,该实验结果反映疼痛表情对时距知觉的影响在秒上秒下的作用机制可能不同,在秒下主要是通过唤醒影响,在秒上则可能由唤醒和注意共同调节。
Abstract: The aim of the current study was using a temporal generalization task and a temporal bisection task to explore whether facial pain could affect subsecond (200~800 ms) and suprasecond (1400- 2600 ms) time perception. Twenty six participants (fifteen males) participated in bisection task, which consisted of two blocks with different stimulus durations (200~800 ms vs. 1400~2600 ms), the order of them was counterbalanced across participants. In the block with 200~800 ms durations, the block consisted of a learning phase which used a “short” (200 ms) and a “long” (800 ms) anchor duration, a traing phase and a test phase involving seven probe durations (400, 600, 800, 1000, 1200, 1400 and 1600 ms). The participants were initially presented with the “short” and “long” anchor durations in the form of a light brown rectangle randomly. Then they were trained to press D/K keys to indicate whether the presentation duration of the rectangle was more closer to “short” or “long” anchor duration. A feedback was given after each response. In the test phase, participants were told that the rectangle would be replaced by faces and no feedback presented. Each participant completed 140 trials presented randomly. In another block, the material and the procedure were similar to 200~800 ms condition, except using 1400 ms and 2600ms as “short” and “long” standard duration and 1400,1600,1800,2000,2200,2400,2600 ms as comparison durations. To verify whether the effect of facial pain on time perception was stable. Other twenty six participants (nine males) took part in generalization task, which used a basically same procedure and materials as the time bisection task, without the standard durations was replaced to 500 ms in 200~800 ms condition and 2000 ms in 1400~2600 ms condition, as the demand was changed to judge whether the present duration was "same" or "different" to the standard duration. In temporal bisection task, the results pertaining to PSE revealed a significant main effect of duration , a significant main effect of facial expression, and a significant duration × face interaction, Subsequent Simple-effects Analysis showed that, in subsecond range, the PSE on facial pain was significantly lower than facial neutral, and in suprasecond range, the PSE on facial pain was also significantly lower than facial neutral. The analysis of WR just found a significant main effect of
人组织型纤溶酶原激活剂(t-PA)组合突变体FrGGI在CHO细胞中的高效表达
,培堂,刘士辉
生物工程学报 , 1997,
Abstract: 为了得到t—PA组合突变体FrGGI在CHO细胞中的高效表达,将表达质粒筛选基因启动子上游的增强子(enhancer)去除.构建了FrGGI真核表达质粒pZLFrGGI。酶切线性化后.采用大剂量DNA电击介导法,转染dhfr基因缺陷型中国仓鼠卵巢细胞系(CHO-dhfr-)。氨甲喋呤(MTX)筛选转染细胞,混合加压.挑选克隆。在1×10-7mol/L MTX压力下。获得表达水平达1 500~2500Iu/106细胞·24h的细胞株。此细胞株表达水平稳定,形态良好.倍增时间约为36h.且有进一步提高表达水平的潜能,有望发展为工程细胞株。
一株D型肉毒梭菌的分离和鉴定
王荫椿,,
微生物学报 , 1987,
Abstract: 从我国东海地区的海泥培养物中,分离出一株厌氧性芽孢杆菌。经细菌学、毒素血清学.细菌代谢产物的气相色谱分析及DNA中G+ct001%测定,鉴定为D型肉毒梭菌,编号为D85501。与国际参考菌株D359对照,D85 501菌株具有D型肉毒梭菌的总特性,还有自身的特点,是D型肉毒梭菌中的一新株,是我国分离的首株D型肉毒梭菌。
西藏羌塘中部古特提斯洋残片?————来自果干加年山变质基性岩地球化学证据
,李才,小朋,

中国科学 地球科学 中国科学 地球科学 , 2007,
Abstract: ?羌塘中部果干加年山发现一套N-MORB型变质基性岩,岩石主要为具有残余堆晶结构的辉长岩和玄武岩.岩石呈近东西向分布,以角度不整合产在上三叠统望湖岭组之下.地球化学分析表明,SiO2含量在45.18%~53.42%之间,TiO2含量在1%~2.67%之间,Al2O3含量在16.75%~21.52%之间,CaO含量在7.03%~11.13%之间,K2O含量在0.05%~0.38%;稀土元素配分曲线呈弱亏损型至平坦型,微量元素比值蛛网图与洋中脊玄武岩的类似,结合其地球化学特征认为,变质基性岩原岩可能形成于大洋中脊或成熟的弧后盆地环境,推测其为古特提斯洋的残片.
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