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    题名 作者 年代 出处 被引量
1美国公共行政重建运动:从“狂热”的反国家主义到90年代“适度”的反国家主义(上)显示文摘里查德.J.斯蒂尔曼(RichardJ.Stiuman II) 闻道 1999北京行政学院学报1999,,4:28
2黑龙江五大连池火山群地壳电性结构显示文摘对1997年在黑龙江五大莲池火山群观测的7条大地电磁测深剖面资料进行重新处理,对全部测点的实、虚感应矢量和视电阻率曲线等参数的分布特征进行了详细分析,应用NLCG二维反演方法对3条近东西向剖面数据进行了反演,获得的深部电性结构结果显示:五大莲池火山群中的笔架山-老黑山-火烧山火山链上的火山规模明显大于南、北格拉球火山链和东、西焦得布火山链,该带火山活动有从南西向北东推移的规律;以笔架山-老黑山-火烧山火山链为中心在地下约几百米深度到20km左右,存在一个北北东走向、上宽下窄、北宽南窄似铆钉的状体,该块体随着深度的增加其电阻率值从上千欧姆米逐渐减小到小于1欧姆米;在深度约20km以下铆钉的主体仍然显示有向深处延伸的趋势,推测一直穿过地壳与上地幔连接;在深度4~8km左右火烧山、老黑山和笔架山东、西两侧存在低阻块体;结合S波速度、小震活动以及地热研究结果分析,推测笔架山-老黑山-火烧山火山链在地壳内随着深度增大存在不同凝固程度的岩浆系统。詹艳 赵国泽 王继军 肖骑彬 汤吉 Rokityansky II 2006岩石学报2006,22,6:24
3Delayed gastric emptying following pancreaticoduodenectomy:Incidence,risk factors,and healthcare utilization显示文摘AIM To characterize incidence and risk factors for delayed gastric emptying(DGE) following pancreaticoduodenectomy and examine its implications on healthcare utilization. METHODS A prospectively-maintained database was reviewed. DGE was classified using International Study Group of Pancreatic Surgery criteria. Patients who developed DGE and those who did not were compared. RESULTS Two hundred and seventy-six patients underwent pancreaticoduodenectomy(PD)(> 80% pyloruspreserving, antecolic-reconstruction). DGE developed in 49 patients(17.8%): 5.1% grade B, 3.6% grade C. Demographic, clinical, and operative variables were similar between patients with DGE and those without. DGE patients were more likely to present multiplecomplications(32.6% vs 4.4%, ≥ 3 complications, P < 0.001), including postoperative pancreatic fistula(POPF)(42.9% vs 18.9%, P = 0.001) and intra-abdominal abscess(IAA)(16.3% vs 4.0%, P = 0.012). Patients with DGE had longer hospital stay(median, 12 d vs 7 d, P < 0.001) and were more likely to require transitional care upon discharge(24.5% vs 6.6%, P < 0.001). On multivariate analysis, predictors for DGE included POPF [OR = 3.39(1.35-8.52), P = 0.009] and IAA [OR = 1.51(1.03-2.22), P = 0.035].CONCLUSION Although DGE occurred in < 20% of patients after PD, it was associated with increased healthcare utilization. Patients with POPF and IAA were at risk for DGE. Anticipating DGE can help individualize care and allocate resources to high-risk patients.Somala Mohammed George Van Buren II Amy Mc Elhany Eric J Silberfein William E Fisher 2017World Journal of Gastrointestinal Surgery2017,9,3:13
4A new cyamodontoid placodont from Triassic of Guizhou, China显示文摘A new cyamodontoid placodont is named (Pse-phochelys polyosteoderma gen. et. sp. nov.) and described based on a three-dimensionally preserved specimen. The material comes from the Wayao Member of the Falang Formation (Carnian, Late Triassic) in Guizhou Province, southwestern China. The skull of Psephochelys shows a unique combination of characteristics observed in Psepho-derma and Placochelys, and the carapace is diagnostic of a new taxon as well. The ventral dermal armor of Psephochelys differs from all other known cyamodontoids in that it comprises irregular marginal osteoderms in loose contact with each other, and gastralia between them. The cranial suture pattern is in part difficult to analyze due to apparent co-ossification of elements, or poor delimitation of sutures. This affects primarily the demarcation of the nasal from the prefrontal, and the relation between the anterior part of the parietal, posterior ends of the frontals, and postfrontals. However, the postfrontal appears to enter theLI Chun & O. RieppelInstitute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China The Field Museum, Chicago, II 60605-2496, USA 2002Chinese Science Bulletin2002,47,5:10
5强脉冲离子注入中的脉冲能量效应研究显示文摘在脉冲离子束流密度为15-120A/cm2、脉宽为50-150ns、加速电压为150-260kV范围内,在1×104cm-2的低注量水平上,研究了高功率Cn++H+混合离子束注入45号钢样品的强脉冲能量效应.摩擦磨损和微观硬度测量以及SEM和X射线衍射分析表明,上述低注量强脉冲离子束注入可以改变材料表面的微观结构和力学特性,而且强烈依赖于单个脉冲离子束的功率密度和能量密度,在相同离子注量条件下,普通C++H+离子注入对45号钢样品表面微硬度和摩擦系数未见明显影响.直接证明了强脉冲能量效应在离子注入中是相对独立于注入元素掺杂效应的又一可利用的重要效应.基于一维导热模型,讨论了强脉冲能量效应以及脉冲离子束功率密度对离子束材料表面改性的作用。赵渭江 颜莎 乐小云 韩宝玺 薛建明 王宇钢 Remmev G E Opekounov M S Isakov I F Grushin II 2000核技术2000,23,10:8
6幔源包体和中国东部现代弧后地热标志显示文摘利用矿物学、岩石学、组构,显微构造和红外光谱的综合分析方法,研究了福建省明溪石榴石和尖晶石-石榴石二辉橄榄岩包体。根据Bertrand和Mecier温度计、Nickel和Green压力计方法,利用TEMPEST最新程序分别计算了包体平衡温度和压力,其变化范围为:1300K,1.9GPa(60km)至1500K 2.6GPa(80km)。由包体温压资料推断的明溪地区地热与实测地表热流量(70mW/m^2)一致。地热特征、包体矿物显微构造和优选方位与现代伸展弧后环境的岩石圈减薄作用是一致的。金振民 H.W.Green II R.S.Borch 金淑燕 T. N. Tracy T.E.Young 1993中国科学(B辑)1993,23,4:8
7Pancreatic function testing: Here to stay for the 21st century显示文摘The diagnosis of Chronic Pancreatitis (CP) is based on the detection of abnormal structure or function of the diseased pancreas. The pancreatic function tests more accurately determine the presence of CP than tests of structure, especially for early stage disease. The function tests can be divided into two categories: non- invasive and invasive. The invasive 'tube' tests can reliably detect mild, early CP, but are only available at a few referral centers and tend to be poorly tolerated by patients. The non-invasive tests are easy to obtain, but tend to perform poorly in patients with early, mild disease. Therefore, no one test is useful in all clinica situations, and a detailed understanding of the rational, pathophysiologic basis, strengths, and limitations of various tests is needed. This review highlights the role of various pancreatic function tests in the diagnosis of CP including fecal fat analysis, fecal elastase, feca chymotrypsin, serum trypsin, the secretin stimulation test, the cholecystokinin (CCK) stimulation test, the combined secretin-CCK stimulation test, the intraducta and endoscopic secretin stimulation tests, and the functional magnetic resonance imaging of the pancreas after secretin stimulation.John G Lieb II Peter V Draganov 2008World Journal of Gastroenterology2008,14,20:8
8Pancreatic endometrial cyst mimics mucinous cystic neoplasm of the pancreas显示文摘Pancreatic cysts include a variety of benign, premalignant, and malignant lesions. Endometrial cysts in the pancreas are exceedingly rare lesions that are difficult to diagnose pre-operatively. This report describes the findings in a 43-year-old patient with a recent episode of acute pancreatitis who presented with a large cyst in the tail of the pancreas. Imaging demonstrated a loculated pancreatic cyst, and cyst fluid aspiration revealed an elevated amylase and carcinoembryonic antigen. The patient experienced an interval worsening of abdominal pain, fatigue, diarrhea, and a 15-pound weight loss 3 mo after the initial episode of pancreatitis. With concern for a possible pre-malignant lesion, the patient underwent a laparoscopic distal pancreatectomy with splenectomy, which revealed a 16cm×12cm×4cm lesion. Final histopathology was consistent with an intra-pancreatic endometrial cyst. Here we discuss the overlapping imaging and laboratory features of pancreatic endometrial cysts and mucinous cystic neoplasms of the pancreas.Michael A Mederos Nicole Villafane Sadhna Dhingra Carlos Farinas Amy Mc Elhany William E Fisher George Van Buren II 2017World Journal of Gastroenterology2017,23,6:7
9Photocatalytic degradation of paraquat using nano-sized Cu-TiO_2 /SBA-15 under UV and visible light显示文摘Photocatalytic degradation of paraquat using mesoporous-assembled Cu-TiO2 /SBA15 under UV and visible light was investigated.The catalyst was synthesized by impregnation of Cu-TiO2 colloids onto SBA-15.The colloids of Cu-TiO2 were prepared via solgel method while the mesoporous support was prepared using hydrothermal technique.The catalyst was characterized using X-ray diffraction,nitrogen adsorption-desorption,transmission electron microscopy,UV diffuse reflectance spectroscopy,Zeta potential and X-ray adsorption spectroscopy.Results from characterizations showed that Cu doped TiO2 had a small crystalline size and was welldispersed on SBA-15.The inclusion of SBA-15 significantly enhanced the photocatalytic activity of the catalyst.Among the three types of undoped catalyst in this study (P25,TiO2,TiO_2 /SBA-15),TiO2 /SBA-15 yielded the highest degradation of paraquat for all pH under UV illumination.Meanwhile 2 wt.% Cu-TiO2 /SBA-15 yielded the highest activity under visible light.Maurice G.Sorolla II Maria Lourdes Dalida Pongtanawat Khemthong Nurak Grisdanurak 2012Journal of Environmental Sciences2012,24,6:6
10Glehnia fittoralis Extract Promotes Neurogenesis in the Hippocampal Dentate Gyrus of the Adult Mouse through Increasing Expressions of Brain-Derived Neurotrophic Factor and Tropomyosin-Related Kinase B显示文摘Joon Ha Park Bich Na Shin Ji Hyeon Ahn Jeong Hwi Cho Tae-Kyeong Lee Jae-Chul Lee Yong Hwan Jeon II Jun Kang Ki-Yeon Yoo In Koo Hwang Choong Hyun Lee Yoo Hun Noh Sung-Su Kim Moo-Ho Won Jong Dai Kim 2018Chinese Medical Journal2018,,6:6
11MODELING OF CONTROLLED THERMO-MECHANICAL PROCESSING OF TUBES FOR ENHANCED MANUFACTURING AND PERFORMANCE显示文摘An integrated mathematical model to simulate seamless tube rolling processes has been developed at The Timken Company. The model is capable of simulating the thermal, deformation and microstructure evolution in the piercing, elongating and reducing/sizing and the austenite decomposition in the mill annealing and cooling operations. Finite difference schemes are employed to model cooling, reducing/sizing and stretch reducing, and finite-element schemes are employed to simulate piercing and elongating. The model predicts the thermal history, deformation, rolling load, torque, recrystallization and grain growth in hot tube rolling, austenite decomposition in cooling or annealing, and the final structure-properties. In this paper mathematical models which are employed to describe the thermal, deformation and microstructure evolution along with the modeling results are presented. The developed 'tube rolling mill in the computer' provides a powerful tool for engineers for product and process development, process control, process optimization and quality control.D. Jin E. D. Dominik R. V. Kolarik II J. E. Ives and E. B. Damm (The Timken Company, 1835 Dueber Avenue, S.W., Canton, Ohio 44706-0932, U.S.A.) 2000Acta Metallurgica Sinica(English Letters)2000,13,2:5
12Antidiarrhoeal activity of leaf methanolic extract of Rauwolfia serpentina显示文摘Objective:To evaluate the antidiarrhoeal property of methanol extract of the leaves of Rauwolfia serpentina(R. serpentina) in experimental diarrhoea induced by castor oil in mice.Methods:Doses of 100, 200 and 400 mg/kgR. serpentinaleaf methanol extracts were administered to castor oil induced diarrhoea mice to determine its antidiarrhoeal activity.Results:All doses of the extract and the reference drug atropine sulphate(3 mg/kg, i.p.) produced a dose-dependent reduction in intestinal weight and fluid volume. The extracts also significantly reduced the intestinal transit in charcoal meal test when compared to diphenoxylate Hcl(5 mg/kg, p.o.).Conclusions:The results show that the extract of R. serpentin a leaves has a significant antidiarrhoeal activity and supports its traditional uses in herbal medicine.Ezeigbo II Ezeja MI Madubuike KG Ifenkwe DC Ukweni IA Udeh NE Akomas SC 2012Asian Pacific Journal of Tropical Biomedicine2012,2,6:4
13TiO2 nanotube branched tree on a carbon nanofiber nanostructure as an anode for high energy and power lithium ion batteries显示文摘Taeseup Song Hyungkyu Han Heechae Choi Jung Woo Lee Hyunjung Park Sangkyu Lee Won II Park Seungchul Kim Li Liu Ungyu Paik 2014Nano Research2014,7,4:4
14Early successes and late failures in the prevention of post endoscopic retrograde cholangiopancreatography显示文摘Acute pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). The only way to prevent this complication is to avoid an ERCP all together. Because of the risks involved, a careful consideration should be given to the indication for ERCP and the potential risk/benefit ratio of the test. Once a decision to perform an ERCP is made, the procedure should be carried out with meticulous care by an experienced endoscopist, and with a minimum of pancreatic duct opacification. Several pharmacologic agents have been tested, but to date the most important method of reducing post ERCP pancreatitis is the placement of pancreatic stent. Pancreatic stents should be placed in all patients at high risk of this complication such as those undergoing pancreatic sphincterotomy, pancreatic duct manipulation and intervention, and patients with suspected sphincter of Oddi dysfunction. Pancreatic stents should be also considered in patients requiring precut sphincterotomy to gain biliary access.John G Lieb II Peter V Draganov 2007World Journal of Gastroenterology2007,13,26:4
15Dispersal patterns of exotic forest pests in South Korea显示文摘侵略种类在生态的社区和生态系统上有潜在地破坏的效果。在南朝鲜理解异国情调的森林害虫的侵略过程,我们考察了异国情调的森林害虫的四主要的种:松针胆量小蚊(Thecodiplosis japonensis ) ,松枯萎松木头线虫(Bursaphelenchus xylophilus ) 引起的疾病,秋天 webworm (Hyphantria cunea ) 和黑松韧皮可伸缩(Matsucoccus thunbergianae ) 。我们考虑他们的生物学,生态学,侵略历史,疏开模式和相关特点,并且管理同样异国情调的种类。在这些之中种类,秋天 webworm 的疏开进程是线性的,而另外的三种显示出 biphasic 模式,作为时间的一个函数显示出经常的范围扩大,在在早侵略阶段的慢疏开以后的很快增加的疏开速度。而且,人的活动加速了他们的扩大,建议损坏的树的人工的运动的那预防将是有用的减缓异国情调的种类的扩大。我们相信这个信息将是有用的为侵略种类建立管理策略。Won II Choi Young-Seuk Park 2012Insect Science2012,19,5:3
16美国公共行政重建运动:从“狂热”的反国家主义到90年代“适度”的反国家主义(下)显示文摘里查德.J.斯蒂尔曼(Richard J.Still man II) 闻道 2000北京行政学院学报2000,,1:3
17Combined pars plana vitrectomy and Baerveldt glaucoma implant placement for refractory glaucoma显示文摘AIM: To evaluate outcomes of combined pars plana vitrectomy and Baerveldt glaucoma implant(PPV-BGI)placement for refractory glaucoma.·METHODS: The medical records of 92 eyes(89patients) that underwent PPV-BGI were retrospectively reviewed, including 43 eyes with neovascular glaucoma(NVG) and 49 eyes with other types of glaucoma(non-NVG).·RESULTS: Outcome measures were visual acuity(VA),intraocular pressure(IOP), glaucoma medical therapy,complications, and success [VA >hand motions(HM),IOP ≥6 mm Hg and ≤21 mm Hg, no subsequent glaucoma surgery]. Cumulative success rates for the non-NVG group and NVG group were 79% and 40% at1 y, respectively(P =0.038). No difference in the rates of surgical success were found between pars plana and anterior chamber tube placement. Preoperative IOP(mean±SD) was 30.3±11.7 mm Hg in the Non-NVG group and 40.0 ±10.6 mm Hg in the NVG group, and IOP was reduced to 15±9.5 mm Hg in the non-NVG group and 15±10.5 mm Hg in the NVG at 1y. Number of glaucoma medications(mean ±SD) decreased from 2.7 ±1.3 in the non-NVG group and 2.8 ±1.3 in the NVG group preoperatively to 0.76 ±1.18 in the non-NVG group and0.51±1.00 in the NVG group at 1y. Improvement in VA of≥2 Snellen lines was observed in 25(27%) eyes,although only 33% of non-NVG eyes and 2.3% of NVG eyes maintained VA better than 20/200 at 1y. Nonclearingvitreous hemorrhage was the most common postoperative complication occurring in 16(17%) eyes,and postoperative suprachoroidal hemorrhages developed in 5(5.4%) eyes.·CONCLUSION: PPV-BGI is a viable surgical option for eyes with refractory glaucoma, but visual outcomes are frequently poor because of ocular comorbidities,especially in eyes with NVG. The location of tube placement does not influence surgical outcome and should be left to the discretion of the surgeon.Thalmon R.Campagnoli Sung Soo Kim William E.Smiddy Steve J.Gedde Donald L.Budenz Richard K.Parrish II Paul F.Palmberg William Feuer Wei Shi 2015International Journal of Ophthalmology(English edition)2015,8,5:3
18Field-effect transistor with a chemically synthesized MoS2 sensing channel for label-free and highly sensitive electrical detection of DNA hybridization显示文摘A field-effect transistor (FET) with two-dimensional (2D) few-layer MoS2 as a sensing-channel material was investigated for label-free electrical detection of the hybridization of deoxyribonucleic acid (DNA) molecules. The high-quality MoS2-channel pattern was selectively formedthrough the chemical reaction of the Mo layer with H2S gas. The MoS2 FET was very stable in an electrolyte and inert to pH changes due to the lack of oxygen-containing functionalities on the MoS2 surface. Hybridization of single-stranded target DNA molecules with single-stranded probe DNA molecules physically adsorbed on the MoS2 channel resulted in a shift of the threshold voltage (Vt,) in the negative direction and an increase in the drain current. The negative shift in Vth is attributed to electrostatic gating effects induced by the detachment of negatively charged probe DNA molecules from the channel surface after hybridization. A detection limit of 10 fM, high sensitivity of 17 mWdec, and high dynamic range of 106 were achieved. The results showed that a bio-FET with an ultrathin 2D MoS2 channel can be used to detect very small concentrations of target DNA molecules specifically hybridized with the probe DNA molecules.Doo-Won Lee Jinhwan Lee II Yung Sohn Bo-Yeong Kim Young Min Son Hunyoung Bark JaehyuckJung Minseok Choi Tae Hyeong Kim Changgu Lee Nae-Eung Lee 2015Nano Research2015,8,7:3
19P2X7 receptor signaling during adult hippocampal neurogenesis显示文摘Neurogenesis is a persistent and essential feature of the adult mammalian hippocampus.Granular neurons generated from resident pools of stem or progenitor cells provide a mechanism for the formation and consolidation of new memories.Regulation of hippocampal neurogenesis is complex and multifaceted,and numerous signaling pathways converge to modulate cell proliferation,apoptosis,and clearance of cellular debris,as well as synaptic integration of newborn immature neurons.The expression of functional P2X7 receptors in the central nervous system has attracted much interest and the regulatory role of this purinergic receptor during adult neurogenesis has only recently begun to be explored.P2X7 receptors are exceptionally versatile:in their canonical role they act as adenosine triphosphate-gated calcium channels and facilitate calcium-signaling cascades exerting control over the cell via calcium-encoded sensory proteins and transcription factor activation.P2X7 also mediates transmembrane pore formation to regulate cytokine release and facilitate extracellular communication,and when persistently stimulated by high extracellular adenosine triphosphate levels large P2X7 pores form,which induce apoptotic cell death through cytosolic ion dysregulation.Lastly,as a scavenger receptor P2X7 directly facilitates phagocytosis of the cellular debris that arises during neurogenesis,as well as during some disease states.Understanding how P2X7 receptors regulate the physiology of stem and progenitor cells in the adult hippocampus is an important step towards developing useful therapeutic models for regenerative medicine.This review considers the relevant aspects of adult hippocampal neurogenesis and explores how P2X7 receptor activity may influence the molecular physiology of the hippocampus,and neural stem and progenitor cells.Hannah C. Leeson Tailoi Chan-Ling Michael D. Lovelace Jeremy C. Brownlie Ben J. Gu Michael W. Weible II 2019Neural Regeneration Research2019,14,10:3
20Effect of surface mechanical attrition treatment of titanium using alumina balls: surface roughness, contact angle and apatite forming ability显示文摘M. JAMESH T. S. N. SANKARA NARAYANAN Paul K. CHU II Song PARK Min Ho LEE 2013Frontiers of Materials Science2013,7,3:3
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