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    题名 作者 年代 出处 被引量
1退耕还林政策对农户生计的影响研究——基于家庭结构视角的可持续生计分析显示文摘以往关于退耕还林政策的分析,较少考虑微观的家庭人口因素。本研究在可持续生计分析框架下引入农户的家庭结构,并基于此框架使用农户模型具体分析了退耕还林政策对农户生计的影响。利用陕西周至县的农户调查数据进行实证研究,结果表明:家庭结构能够影响生计资本水平和时间配置,退耕还林政策对农户生计的作用因家庭结构而不同。退耕还林政策既没有针对生计资本贫乏的农户,也不一定能够促使农业劳动力向非农转化,并进一步提升农户的收入。有小孩但没有老年人的家庭较少从事外地打工活动,收入相对偏低,他们更依赖退耕补助。相关政策的制定和实施应当考虑家庭结构等人口因素。李树茁 梁义成 MARCUS W.FELDMAN GRETCHEN C.DAILY 2010公共管理学报2010,7,2:110
2A community-derived classification for extant lycophytes and ferns显示文摘发展史长通知了蕨类植物分类。当我们推断进化的树的能力改善了,针对认出生来的组的分类变得逐渐地预兆、稳定。这里,我们为 lycophytes 和蕨纲植物提供一个现代、全面分类,在下面,利用一条基于社区的途径类水平。我们 monophyly 用作主要标准让 taxa,而且目的识别保存两个广泛地被接受的存在 taxa 和界限并且与我们蕨类植物发展史的理解一致。总共,这个分类对待一在 337 个类, 51 个家庭, 14 目,和二个班估计了 11  916 种类。这个分类没在 lycophyte 和蕨纲植物上作为最后的词被打算分类,而是当前的假设的概括陈述,源于最好的可得到的数据并且在问题由熟悉植物的那些大多数塑造了。我们希望它将在蕨类植物上为最近的文学的那些想要的参考用作一个资源发展史和分类,为指导未来调查的一个框架,和推进讲话的刺激。Eric Schuettpelz Harald Schneider Alan R. Smith Peter Hovenkamp Jefferson Prado Germinal Rouhan Alexandre Salino Michael Sundue Thafs Elias Almeida Barbara Parris Emily B. Sessa Ashley R. Field Andre Luis de Gasper Carl J. Rothfels Michael D. Windham Marcus Lehnert Benjamin Dauphin Atsushi Ebihara Samuli Lehtonen Pedro Bond Schwartsburd Jordan Metzgar Li-Bing Zhang Li-Yaung Kuo Patrick J. Brownsey Masahiro Kato Marcelo Daniel Arana Francine C. Assis Michael S. Barker David S. Barrington Ho-Ming Chang Yi-Han Chang Yi-Shan Chao Cheng-Wei Chen De-Kui Chen Wen-Liang Chiou Vinicius Antonio de Oliveira Dittrich Yi-Fan Duan Jean-Yves Dubuisson Donald R. Farrar Susan Fawcett Jose Maria Gabriel y Galan Luiz Armando de Araujo Goes-Neto Jason R. Grant Amanda L. Grusz Christopher Haufler Warren Hauk Hai He Sabine Hennequin Regina Yoshie Hirai Layne Huiet Michael Kessler Petra Korall Paulo H. Labiak Anders Larsson Blanca Leen Chun-Xiang Li Fay-Wei Li Melanie Link-Perez Hong-Mei Liu Ngan Thi Lu Esteban I. Meza-Torres Xin-Yuan Miao Robbin Moran Claudine Massi Mynssens Nathalie Nagalingum Benjamin Ollgaard Alison M. Paul Jovani B. de S. Pereira Leon R. Perrie Monica Ponce Tom A. Ranker Christian Schulz Wataru Shinohara Alexander Shmakov Erin M. Sigel Filipe Soares de Souza Lana da Silva Sylvestre Weston Testo Luz Amparo Triana-Moreno Chie Tsutsumi Hanna Tuomisto IvAn A. Valdespino Alejandra Vasco Raquel Stauffer Viveros Alan Weakley Ran Wei Stina Weststrand Paul G. Wolf George Yatskievych Xiao-Gang Xu Yue-Hong Yan Liang Zhang Xian-Chun Zhang Xin-Mao Zhou 2016Journal of Systematics and Evolution2016,54,6:44
3保障自然资本与人类福祉:中国的创新与影响显示文摘1引言近十年来,将生态系统作为重要资本的理念迅速普及。从全球来看,这一理念正逐步体现到农业、水利、能源、城市、健康、渔业、林业、矿业等领域及其相关基础设施建设等许多部门的工作中,以及社区、企业、政府机构等的构架与决策中。为了扭转地球生命支持系统的退化趋势、提高人类福祉,迫切需要将自然资本价值整合到发展决策中的严谨科学方法。为了满足决策者的迫切需求,从事生态学的科研工作者面临如下四个方面的挑战,即:(1)在生态学、经济、社会、制度和管理的角度,认识生态系统服务、人类福祉以及他们的内在联系;(2)开发生态系统服务功能评价与决策应用的科学实用的工具;(3)开展在关键决策中能做出新理解和采用新工具的试点和示范;(4)让决策者实现决策方式的转型和永久改变。Gretchen C.Daily 欧阳志云 郑华 李树茁 王玉宽 Marcus Feldman Peter Kareiva Stephen Polasky Mary Ruckelshaus 2013生态学报2013,33,3:40
4中国男性婚姻挤压模式研究显示文摘随着20世纪80年代以来的高出生性别比队列陆续进入婚姻市场,中国男性婚姻挤压问题日益凸显。在此背景下,文章使用人口普查数据,采用人口学分析方法研究当前中国男性婚姻挤压模式的变动规律,试图完善现有的婚姻挤压理论。研究发现,从时期角度分析,当前中国男性婚姻挤压主要表现为农村地区的超低初婚水平的挤压模式,农村男性初婚概率的年龄分布受挤压明显且平均初婚年龄的变动出现停滞,男性婚姻挤压区域分布相对集中并已出现扩散趋势。从队列角度分析,农村未婚男性受初婚概率偏低和死亡概率偏高的双重挤压,其终身结婚期待率在各个年龄段均低于城镇男性,成婚期望年数则均高于城镇男性,说明农村地区实际婚姻挤压程度比时期指标所反映的更加严重。当前农村男性婚姻挤压状况可能构成未来中国男性总体的婚姻挤压态势。最后,文章给出了当前农村大龄未婚男性年龄的测度依据。果臻 李树茁 Marcus W.Feldman 2016中国人口科学2016,,3:33
5我国部分医院ST段抬高急性冠状动脉综合征再灌注治疗登记研究显示文摘目的了解目前我国ST段抬高急性冠状动脉综合征(ACS)再灌注治疗实施状况及近期预后。方法入选来自5个地区不同级别(从中心城市的三级医院到县级医院)20个中心的ST段抬高ACS或怀疑为新出现的左束支传导阻滞的患者共518例,对其临床特点,再灌注治疗情况及预后进行评价,并进行3个月随访。其中男371例,女147例,平均年龄(65±11)岁。随访率为99.6%。结果患者自症状开始到就诊的中位数时间为4 h,20%的患者在症状出现12 h以上就诊。292例(56%,292/518)ST段抬高ACS患者接受了再灌注治疗,其中134例(46%,134/292)接受了急诊冠状动脉介入(PCI)治疗,158例(54%,158/292)为溶栓治疗,溶栓治疗中尿激酶的应用占67%。从就诊到开始PCI的中位数时间(door-to-cath)为110 min,从患者就诊到开始溶栓的中位数时间为65 min。多因素回归分析显示,高龄(≥75岁,P<0.01)、有心肌梗死病史(P<0.01)及心力衰竭病史(P< 0.05)是未接受再灌注治疗的预测因素。非再灌注治疗组出院(P<0.01)和3个月病死率(P< O.01)、出院(P<0.01)和3个月心力衰竭发生率(P<0.01),以及3个月死亡或再梗死和死亡或再梗死或卒中的联合事件发生率(均P<0.01)均明显高于再灌注治疗组,但不同的再灌注治疗方法对近期预后无明显影响。相似的结果也见于症状出现12 h以内就诊患者的亚组分析。结论再灌注治疗是改善ST段抬高ACS患者预后的关键措施。我国ST段抬高ACS再灌注治疗有待于进一步提高,不仅要提高再灌注治疗率,更应缩短就诊和再灌注治疗前的延误时间,并加强高危患者的再灌注治疗。于丽天 朱俊 Rebecca Mister 章晏 李建冬 王多劳 刘力生 Marcus Flather 2006中华心血管病杂志2006,34,7:30
6HAART治疗20例艾滋病患者疗效评估显示文摘目的 评价高效抗逆转录病毒疗法(Highly active antiretroviral therapy,HAART)对我国艾滋病(AIDS)患者的疗效.方法 对20例接受免费HAART治疗1~2年(平均18个月)的HIV-1感染的晚期患者进行横断面调查,检测HIV-RNA病毒载量、CD4^+T淋巴细胞绝对计数、HIV特异性细胞毒性T淋巴细胞(CTL)应答、常规生化检验和临床指标观察.结果 所有观察对象在HAART治疗1~2年(平均18个月)后,临床症状明显改善:大部分患者病毒复制得到有效抑制,80%患者血浆中HIV-RNA载量在检测水平以下,CD4^+T淋巴细胞绝对计数平均356.9±155.7/mm^3,其中8例(40%)大于400/mm^3;CTL应答频率和效应在每个蛋白区都有应答,对Nef蛋白应答较为突出.结论 HAART治疗对我国HIV/AIDS患者疗效显著,能提高HIV-1感染者的生活质量,降低机会性感染,并使部分免疫功能重建,具有较高的安全性和耐受性.刘小利 王少杨 翟嵩 庄严 李新红 康文臻 于旭 Marcus Altfeld Bruce Walker 孙永涛 2006中国艾滋病性病2006,12,2:27
7离土与离乡:西部山区农户的非农兼业研究显示文摘在可持续生计分析框架下(SLF),本文发展了一个农户模型,阐释了在多重不完全市场条件下,农户的资本禀赋包括人力资本的分布特征和金融可及性等,如何决定农户参与两类不同的非农兼业活动。基于陕西周至山区的农户调查数据,文章的实证结果表明:高人力资本水平是外地打工兼业的关键因素,而本地非农经营兼业还要求农户具备较高的物质资本和社会关系资本等。梁义成 Marcus W.Feldman 李树茁 Gretchen C.Daily 黎洁 2010世界经济文汇2010,,2:26
8Reduced bone mineral density and altered bone turnover markers in patients with non-cirrhotic chronic hepatitis B or C infection显示文摘AIM: Previous studies suggest that loss of bone mineral density (BMD) frequently occurs in patients with chronic viral liver disease, presenting with histologically proven liver cirrhosis. However, little is known about the occurrence of bone disease in non-cirrhotic patients with chronic hepatitis B or C. Therefore, it was the aim of this study to evaluate this particular population for BMD and bone turnover markers.METHODS: Biochemical markers of bone turnover and BMD were measured in 43 consecutive patients with HCV (n = 30)or HBV (n = 13) infection without histological evidence for liver cirrhosis. Mean age was 49 years (range 26-77 years). BMD was measured by dual X-ray absorptiometry in the femoral neck (FN) and the lumbar spine (LS) region. In addition, bone metabolism markers were measured.RESULTS: BMD was lowered in 25 (58%) of the patients with chronic hepatitis B or C (FN: 0.76 (0.53-0.99); LS:0.96 (0.62-1.23) g/cm2). Eight (32%) osteopenic patients were diagnosed with osteoporosis. Bone-specific alkaline phosphatase (P = 0.005) and intact parathyroid hormone (iPTH) (P = 0.001) were significantly elevated in the more advanced stages of fibrosis. Mean 7-score value was lower in patients with chronic hepatitis C as compared to patients suffering from chronic hepatitis B; however, the difference was not statistically significant (P = 0.09).CONCLUSION: There was a significantly reduced BMD in non-cirrhotic patients with chronic hepatitis B or C infection. Alterations of bone metabolism already occurred in advanced liver fibrosis without cirrhosis. According to our results, these secondary effects of chronic viral hepatitis should be further investigated.Ingolf Schiefke Andreas Fach Marcus Wiedmann Andreas V.Aretin Eva Schenker Gudrun Borte Manfred Wiese Joachim Moessner 2005World Journal of Gastroenterology2005,11,12:23
9中国婚姻挤压问题研究显示文摘目前,中国的男性婚姻挤压及其后果引起了广泛关注,但大部分研究把婚姻挤压归结于性别结构因素,而忽略了人口的年龄结构因素,还有些研究考察年龄结构贡献的方法存在一些不足。文章构建了婚配性别比及其年龄结构和性别结构的分解方法,并根据2010年人口普查数据及预测数据,研究了中国2010-2050年婚姻挤压中年龄结构因素和性别结构因素的影响。结果发现,2010-2020年婚姻挤压以年龄结构因素为主导,2020-2034年性别结构因素的作用增强,而年龄结构因素减弱。2034-2045年,男性过剩主要是性别结构因素作用的结果,年龄结构因素不起作用或者起到减缓男性过剩的作用。姜全保 李晓敏 Marcus W.Feldman 2013中国人口科学2013,,5:21
10乳腺癌患者配偶夫妻沟通干预方案的修订与实施显示文摘不良的沟通方式会影响乳腺癌夫妻关系的调适。本文详细介绍了乳腺癌患者配偶夫妻沟通干预方案的本土化修订过程、内容、实施方法及效果的初步评价,旨在帮助配偶学会良好的夫妻沟通方法,为乳腺癌家庭支持研究提供参考。李智 刘均娥 陈双琴 Frances Marcus Lewis Ellen H.Zahlis 2016中国护理管理2016,16,2:19
11农村大龄未婚男性家庭生命周期研究显示文摘文章通过生命表技术和概率理论,测算了大龄未婚男性家庭生命周期各阶段的长度。研究发现大龄未婚男性在60岁时,丧父的累积概率达到0.8,丧母的概率达到0.6;丧父丧母之后大龄未婚男性单独生活16年。不同的年龄参数对测度的各阶段长度有影响。姜全保 果臻 李树茁 Marcus W.Feldman 2009中国人口科学2009,,4:17
12Immune cells in term and preterm labor显示文摘Nardhy Gomez-Lopez Derek StLouis Marcus A Lehr Elly N Sanchez-Rodriguez Marcia Arenas-Hernandez 2014Cellular & Molecular Immunology2014,11,6:17
13极谱法测定无氧介质中根系氧气输导显示文摘介绍了利用极谱法测定凤眼莲 (Eichhorniacras sipesSolm .)、菰 (Zizanialatifolia (Geiseb)Stapf)、石菖蒲(AcorustartarinowiiSchott)、慈菇 (SagitarriasagittifoliaLinn .)、香蒲 (TyphaangustifoliaLinn .)等多种湿生植物根系在无氧介质中氧气的对外扩散速率 (ODR)。实验结果表明 ,对于同种植物而言 ,新生根较老根的氧气扩散速率快。根尖区 (约 0~ 5mm范围内 )氧气扩散速率最大 ,氧化活力最强。愈往上愈小 ,根基部的氧气输出速率接近为零 ,氧化活力几乎可以忽略。对于根长相同的不同种植物而言 ,香蒲的ODR最大 。吴振斌 贺锋 程旺元 成水平 Marcus J Darwent Bill Armstrong Jean Armstrong 2000植物生理学报(0257-4829)2000,26,3:16
14中国高龄老年人的生活自理能力变化轨迹及队列差异——基于固定年龄与动态年龄指标的测算显示文摘文章基于中国老年人健康长寿影响因素调查(CLHLS)数据,利用混合效应的多层线性模型对1899~1908、1909~1918和1919~1928年3个出生队列的中国高龄老年人的生活自理能力衰退过程进行了分析,以揭示这一过程中的年龄、队列效应以及内部异质性。分析结果表明,年龄效应和队列效应同时存在于高龄老年人的生活自理能力衰退过程。不同年龄的老年人在死亡前的生活自理能力衰退过程具有趋同性,与日历年龄相比,尚余存活时间与生活自理能力变化之间的关联更为密切。高龄老年人的生活自理能力变化存在显著的队列差异,不同社会经济背景、童年经历、健康行为以及生活环境对高龄老年人的生活自理能力变化轨迹影响显著,也是造成队列差异的重要因素。张文娟 Marcus W. Feldman 杜鹏 2019人口研究2019,43,3:16
15Clostridium difficile causing acute renal failure: Case presentation and review显示文摘AIM: Clostridium difficile infection is primarily a nosocomial infection but asymptomatic carriers of Clostridium difficile can be found in up to 5% of the general population.Ampicillin, cephalosporins and clindamycin are the antibiotics that are most frequently associated with Clostridium difficile-associated diarrhea or colitis. Little is known about acute renal failure as a consequence of Clostridium difficile-associated diarrhea.METHODS: In this case report, we describe the course of Clostridium difficile-associated diarrhea in an 82-yearold patient developing acute renal failure. Stopping the offending agent and symptomatic therapy brought a rapid improvement of diarrhea and acute renal failure, full recovery was gained 18 d after admission. In a systematic review we looked for links between the two conditions.RESULTS: The link between Clostridium difficilr-associated diarrhea and acute renal failure in our patient was most likely volume depletion. However, in experimental studies a direct influence of Clostridium difficile toxins on renal duct cells could be shown.CONCLUSION: Rapid diagnosis, nonspecific supportive treatment and specific antibiotic treatment, especially in the elderly, may lower excess mortality Clostridium difficile-associated diarrhea and renal failure being possible complications.Jasmin Arrich Gottfried H.Sodeck Gürkan Seng(o|¨)lge Christoforos Konnaris Marcus Müllner Anton N.Laggner Hans Domanovits 2005World Journal of Gastroenterology2005,11,8:15
16A survey on artificial intelligence trends in spacecraft guidance dynamics and control显示文摘The rapid developments of artificial intelligence in the last decade are influencing aerospace engineering to a great extent and research in this context is proliferating.We share our observations on the recent developments in the area of spacecraft guidance dynamics and control,giving selected examples on success stories that have been motivated by mission designs.Our focus is on evolutionary optimisation,tree searches and machine learning,including deep learning and reinforcement learning as the key technologies and drivers for current and future research in the field.From a high-level perspective,we survey various scenarios for which these approaches have been successfully applied or are under strong scientific investigation.Whenever possible,we highlight the relations and synergies that can be obtained by combining different techniques and projects towards future domains for which newly emerging artificial intelligence techniques are expected to become game changers.Dario Izzo Marcus Martens Binfeng Pan 2019Astrodynamics2019,3,4:15
17Epigenetic mechanisms in cardiac development and disease显示文摘在哺乳动物的开发期间,心脏的说明并且最终,对一种特定的心脏的房间类型的系承诺被特定的抄写因素(TF ) 和他们的过细的控制的行动在 epigenetic 水平上完成。在这评论,我们详细说明心脏特定的 TF 怎么与 nucleosome 改变和修改 histone 酶调整为象房间生长和增长那样的进程要求的基因的一个多样的网络在音乐会工作,或对间充质的转变(EMT ) 上皮例如。我们提供几心脏的 TF 例如 Nkx2.5 , WHSC1 , Tbx5 ,和 Tbx1 ,它与发展、先天的心缺点被联系,怎么为 histone 修饰词的招募被要求的例子,例如 Jarid2 , p300 ,和 Ash2l ,并且ATP依赖的改变的酶的部件喜欢 Brg1 , Baf60c ,和 Baf180 。到他们在心脏的基因的各自的地点的这些 TF 的绑定与 histone 标记的一个不同模式与一致,显示心脏的基因网络的精确规定被在 TF 和 epigenetic 修饰词之间的相互作用安排。而且,我们推测那 epigenetic 签名, TF 包括了占有, histone 修正,和全面染色质组织,是管理心脏的形态发生和疾病的内在的机制。Marcus Vallaster Caroline Dacwag Vallaster Sean M.Wu 2012Acta Biochimica et Biophysica Sinica2012,44,1:14
18双重网络嵌入对联合投资形成的影响——基于网络信号视角显示文摘现有文献均孤立地分析风险投资机构(简称VC)嵌入单个网络产生的影响。本文基于网络信号视角研究VC同时嵌入投资机构网络和有限合伙人(简称LP)网络对联合投资形成的影响。以2003年到2015年中国本土VC的数据为样本,本文研究发现:(1)LP的网络位置对VC形成联合投资有显著正向影响;(2)VC的网络位置对其形成联合投资有显著正向影响;(3)随着LP网络位置的提升,VC网络位置对联合投资形成的正向影响会减弱。上述检验结果表明在联合投资形成过程中,VC嵌入投资机构网络与嵌入有限合伙人网络产生的两种信号对缓解逆向选择问题存在替代效应。杨敏利 丁文虎 郭立宏 Marcus Feldman 2018管理评论2018,30,2:14
19Sirolimus inhibits growth of human hepatoma cells alone or combined with tacrolimus, while tacrolimus promotes cell growth显示文摘AIM: Standard immunosuppression after organ transplantation stimulates tumor growth. Sirolimus has a strong antiproliferative and a tumor inhibiting effect. The purpose is to assess the effect on tumor growth of the immunosuppressive compounds sirolimus and tacrolimus alone and in combination on cells of human hepatocellular carcinoma.METHODS: We used the human cell lines SK-Hep 1 and Hep 3B derived from hepatocellular carcinoma. Proliferation analyses after treatment with sirolimus, tacrolimus, or the combination of both were performed. FACS analyses were done to reveal cell cycle changes and apoptotic cell death. The expression of apoptosis-related proteins was estimated by Western blots.RESULTS: Sirolimus alone or combined with tacrolimus inhibited the growth of both cell lines after 5 d by up to 35% in SK-Hep 1 cells, and by up to 68% in Hep 3B cells at 25 ng/mL. Tacrolimus alone stimulated the growth by 12% after 5 ng/mL and by 25% after 25 ng/mL in Hep 3B cells. We found an increase of apoptotic Hep 3B cells from 6 to 16%, and a G1-arrest in SK-Hep 1 cells with an increase of cells from 61 to 82%, when sirolimus and tacrolimus were combined. Bcl-2 was down-regulated in Hep 3B, but not in SK-Hep 1 cells after combined treatment.CONCLUSION: Sirolimus appears to inhibit the growth of hepatocellular carcinoma cells alone and in combination with tacrolimus. Sirolimus seems to inhibit the growth stimulation of tacrolimus.Guido Schumacher Marijke Oidtmann Anne Rueggeberg Dietmar Jacob Sven Jonas Jan M. Langrehr Ruth Neuhaus Marcus Bahra Peter Neuhaus 2005World Journal of Gastroenterology2005,11,10:14
20Percutaneous left atrial appendage closure:Technical aspects and prevention of periprocedural complications with the watchman device显示文摘Transcatheter closure of the left atrial appendage has been developed as an alternative to chronic oral anticoagulation for stroke prevention in patients with atrial fibrillation, and as a primary therapy for patients with contraindications to chronic oral anticoagulation. The promise of this new intervention compared with warfarin has been supported by several, small studies and two pivotal randomized trial with the Watchman Device. The results regarding risk reduction for stroke have been favourable although acute complications were not infrequent. Procedural complications, which are mainly related to transseptal puncture and device implantation, include air embolism, pericardial effusions/tamponade and device embolization. Knowledge of nature, management and prevention of complications should minimize the risk of complications and allow transcatheter left atrial appendage closure to emerge as a therapeutic option for patients with atrial fibrillation at risk for cardioembolic stroke.Sven M bius-Winkler Nicolas Majunke Marcus Sandri Norman Mangner Axel Linke Gregg W Stone Ingo D hnert Gerhard Schuler Peter B Sick 2015World Journal of Cardiology2015,7,2:14
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