mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
白洋淀芦苇湿地生态系统中植硅体的产生和积累研究

植硅体(phytoliths),又称植物蛋白石,存在于大部分植物组织细胞中,主要是依靠植物的根系吸取土壤溶液中的可溶性二氧化硅,在植物细胞或细胞内沉淀硅化而形成的一种固体的非晶质含水二氧化硅颗粒物。植硅体主要组成部分是二氧化硅(67%~95%)、水(1%~12%)、碳(0.1%~6%)及少量的无机元素Na、K、Ca、Fe、AL、Ti等,由于其具有较强的抗分解、抗腐蚀和耐高温等特性,可以长时间较稳定地保存在一些岩石和土壤中,在硅的生物地球化学循环中有着重要的作用,是全球硅循环的重要参与者。虽然植硅体作为生物硅的重要组成部分,在全球硅的生物地球化学循环中占据着重要地位,但在湿地生态系统中植硅体产生和积累研究则鲜见报道。
小分子RNA作为器官移植免疫状态标志物的研究进展

如何准确地监测受者的免疫状态, 并据此制定个体化的免疫抑制方案, 是器官移植领域的重要课题. 小分子RNA(miRNA)是一种可通过降解或翻译靶mRNA的方式在转录后水平调控基因表达的非编码RNA, 已被证实在器官发育、细胞分化和增殖以及功能表达中起着关键作用, 并参与其他多种生物学过程. 随着基因芯片技术的日益成熟, miRNA可作为监测受者术后免疫状态的潜在生物学标志物. 现就相关研究进行综述.
儿童炎症性肠病的诊断与鉴别诊断

炎症性肠病(IBD)是一种病因尚不十分清楚的慢性肠道炎症性疾病,包括溃疡性结肠炎及克罗恩病。前者是一种慢性非特异性结肠炎症,病变主要累及结肠黏膜和黏膜下层;后者为一种慢性肉芽肿性炎症,病变以末段回肠及其邻近结肠为主,呈穿壁性炎症。临床主要表现为腹泻、腹痛和黏液脓血便、肛周病变等,二者均可合并不同程度的全身症状。IBD的诊断基于临床表现、结肠镜、胃镜、小肠放射学检查及对胃肠道各部位的多点活检,已取得完整的组织学评价,并注意排除慢性感染性肠道疾病。
CFD Based Study of Heterogeneous Microclimate in a Typical Chinese Greenhouse in Central China

Indoor microclimate is important for crop production and quality in greenhouse cultivation.This paper focuses on microclimate study based on a computational fluid dynamics(CFD) model of a typical plastic greenhouse(with a sector shape vertical cross-section) popularly used in central China.A radiation model is added into the CFD model so as to simulate coupling of convective transfers and radiative exchanges at the cover and the roof,instead of using the usual coupling approach based on energy balance.In addition,a fractal permeability model is innovatively adopted in the modeling of the crop canopy.Compared the numerical results with measured experimental data,the model simulation is proved with success.This model then is used to explore the microclimate variable distributions in the greenhouse.It shows that the airflow pattern,temperature and humidity profiles are different from those in a sawtooth Mediterraneantype greenhouse.The study suggests that this deliberately developed CFD model can be served as a useful tool in macroclimate research and greenhouse design investigating.
Effects of Drip System Uniformity and Irrigation Amount on Water and Salt Distributions in Soil Under Arid Conditions

The dynamics of water and salt in soil were monitored in the 2010 and 2011 growing seasons of cotton to evaluate the salinity risk of soil under drip irrigation in arid environments for different management practices of drip system uniformity and irrigation amount.In the experiments,three Christiansen uniformity coefficients(CU) of approximately 65,80,and 95%(referred to as low,medium,and high uniformity,respectively) and three irrigation amounts of 50,75,and 100% of full irrigation were used.The distribution of the soil water content and bulk electrical conductivity(EC_b) was monitored continuously with approximately equally spaced frequency domain reflectometry(FDR) sensors located along a dripline.Gravimetric samples of soil were collected regularly to determine the distribution of soil salinity.A great fluctuation in CU of water content and EC_b at 60 cm depth was observed for the low uniformity treatment during the irrigation season,while a relatively stable variation pattern was observed for the high uniformity treatment.The EC_b CU was substantially lower than the water content CU and its value was greatly related to the water content CU and the initial EC_b CU.The spatial variation of seasonal mean soil water content and seasonal mean soil bulk electrical conductivity showed a high dependence on the variation pattern of emitter discharge rate along a dripline for the low and medium uniformity treatments.A greater irrigation amount produced a significantly lower soil salinity at the end of the irrigation season,while the influence of the system uniformity on the soil salinity was insignificant at a probability level of 0.1.In arid regions,the determination of the target drip irrigation system uniformity should consider the potential salinity risk of soil caused by nonuniform water application as the influence of the system uniformity on the distribution of the soil salinity was progressively strengthened during the growing season of crop.
Climate Change Modelling and Its Roles to Chinese Crops Yield

Climate has been changing in the last fifty years in China and will continue to change regardless any efforts for mitigation.Agriculture is a climate-dependent activity and highly sensitive to climate changes and climate variability.Understanding the interactions between climate change and agricultural production is essential for society stable development of China.The first mission is to fully understand how to predict future climate and link it with agriculture production system.In this paper,recent studies both domestic and international are reviewed in order to provide an overall image of the progress in climate change researches.The methods for climate change scenarios construction are introduced.The pivotal techniques linking crop model and climate models are systematically assessed and climate change impacts on Chinese crops yield among model results are summarized.The study found that simulated productions of grain crop inherit uncertainty from using different climate models,emission scenarios and the crops simulation models.Moreover,studies have different spatial resolutions,and methods for general circulation model(GCM) downscaling which increase the uncertainty for regional impacts assessment.However,the magnitude of change in crop production due to climate change(at 700 ppm CO_2 eq correct) appears within ±10% for China in these assessments.In most literatures,the three cereal crop yields showed decline under climate change scenarios and only wheat in some region showed increase.Finally,the paper points out several gaps in current researches which need more studies to shorten the distance for objective recognizing the impacts of climate change on crops.The uncertainty for crop yield projection is associated with climate change scenarios,CO_2 fertilization effects and adaptation options.Therefore,more studies on the fields such as free air CO_2 enrichment experiment and practical adaptations implemented need to be carried out.
Biotic Homogenization Caused by the Invasion of Solidago canadensis in China

Although studies argue that invasive species can cause biotic differentiation,some cases show that biological invasions actually decrease biodiversity through biotic homogenization.The concept of biotic homogenization through the invasion of a certain serious invasive plant species merit more studies.Hence,we used field surveys to quantitatively compare invasive populations of Solidago canadensis(SC) in China with the control sites(adjacent sites to SC present sites yet without the species) and SC native populations in the USA.We found that plant communities in SC invaded habitats shared similarities with those in SC native ranges.Bray-Curtis similarity clearly showed that the composition of plant communities in SC invaded habitats were similar to those in SC native ranges.Both in the native and introduced range,plant communities with SC present were characterized by SC being dominant,significantly lower species richness,α-diversity and β-diversity,as well as a decrease in the correlation coefficient between geographic distance and floristic similarities.SC favors fertile and moist loam habitat,while it dominated in various habitats in China,where more than 20 different dominants should have occurred.In conclusion,serious invasive species can quickly remodel and homogenize diverse communities by dominating them.
Identification of Quantitative Trait Loci for Phytic Acid Concentration in Maize Grain Under Two Nitrogen Conditions

Phytic acid(PA) is the main storage form of phosphorus(P) in seeds.It can form insoluble complexes with microelements,thereby reducing their bioavailability for animals.Identification of quantitative trait loci(QTLs) associated with grain PA concentration(PAC) is essential to improve this trait without affecting other aspects of grain nutrition such as protein content.Using a recombinant inbred line(RIL) population,we mapped QTL for grain PAC,as well as grain nitrogen concentration(NC) and P concentration(PC) in maize under two N conditions in 2 yr.We detected six QTLs for PAC.The QTL for PAC on chromosome 4(phi072-umc1276) was identified under both low-N and high-N treatments,and explained 13.2 and 15.4% of the phenotypic variance,respectively.We identified three QTLs for grain NC,none of which were in the same region as the QTLs for PAC.We identified two QTLs for PC in the low-N treatment,one of which(umc1710-umc2197) was in the same interval as the QTL for PAC under high-N conditions.These results suggested that grain PAC can be improved without affecting grain NC and inorganic PC.
经腹行改良Heller+Dor术治疗贲门失弛缓症的远期疗效评估

目的探讨经腹行改良Heller+Dor术治疗贲门失弛缓症的远期疗效。方法自2001年6月至2009年8月,对28例贲门失弛缓症患者行经腹改良Heller+Dor术,评价其疗效及不良反应。结果28例患者术后随访3~9年,平均5.12年,89.29%(25/28)的患者达到满意的疗效。术后反酸率为10.71%(3/28),其中1例在术后6年出现较为严重的胃灼热症状。术后远期随访示患者吞咽困难评分由术前6.50分降至1.18分;钡餐造影示食管最大直径由术前(3.46±1.16)cm减少至(1.88±0.93)cm;食管测压示食管下括约肌静息压平均下降了10.07mm Hg,上诉3项指标手术前、后比较,差异均有统计学意义(P<0.01)。结论改良Heller+Dor术可以有效治疗贲门失弛缓症和减少术后反酸的发生,远期疗效满意。
Reduction of Ilmenite Through Microwave Plasma

Ilmenite was reduced through microwave plasma-assisted chemical vapor deposition with continuously flowing hydrogen and methane gas. The reduction products were analyzed by XRD and SEM technology, and the component products were TiO_2 -Carbon Nanotubes (CNTs) composite powders. The reduction process was in good agreement with the Jander equation. Compared with other reduction process by kinetics analysis, microwave plasma could significantly facilitate the reduction process at low temperature.
新辅助化疗后隐匿性乳腺癌放射定位保乳术疗效观察

目的:评估新辅助化疗后隐匿性乳腺癌放射定位(ROLL)保乳术的价值。方法:回顾性分析3年间对我院进行新辅助化疗后使用ROLL-~(99m)Tc核素定位保乳术及金属标记物定位保乳术的患者资料,对切除标本重量、切除标本阳性边缘及术后癌转移等情况进行评估。结果:93例ROLL-~(99m)Tc核素定位切除标本的平均重量为52(12~158)g,其中有8例切除标本边缘病理检测阳性。108例金属标记物定位切除标本的平均重量为71(46~116)g,其中有16例切除标本边缘病理检测阳性。结论:ROLL-~(99m)Tc技术相对于金属标记物定位法在临床上具有很大的可行性,可用于一些新辅助化疗患者的保乳术中。
胶质瘤复发与放射性脑损伤的影像研究现状

胶质瘤是最常见的脑内原发性肿瘤,由于其具有浸润性生长的特性,手术难以彻底切除,而且易复发,因此治疗手段为手术切除后辅以放疗及靶向化疗。术后常规放疗可以延长患者的生存期并加强治疗效果,但也会带来负面效应。在接受脑部放疗后的一段时间内(3个月~10年),部分患者会出现不同程度的放射性脑损伤,主要包括由于血-脑屏障破坏所致放射性脑坏死和射线所致广泛脑白质脱髓鞘,放射性脑损伤的最终结果为放射性脑坏死。即使患者行全脑放疗,放射性脑损伤通常也仅出现于原发肿瘤的部位,这种现象的机制目前尚不明确,可能是由于术后原发肿瘤部位周围出现血管性水肿,而使邻近的脑白质更容易被射线损伤。一旦脑内出现新的异常强化病灶,需要鉴别该强化灶是肿瘤复发还是放射性脑损伤。目前用于鉴别两者的诊断方法有扩散加权成像(DWI)、灌注成像(PWI)、三维动脉自旋标记(3D-ASL)、磁共振波谱(MRS)、正电子发射体层摄影术(PET)、单光子发射计算机体层摄影术(SPECT)等。
浅议火探管式自动探火灭火系统

火探管式自动探火灭火系统装置是近年来发展的一种新型自动气体灭火装置,特别适宜扑救相对密闭、体积较小的空间或设备火灾。介绍了该系统工作原理、技术特点、在变配电室的应用方案及应用注意事项。
科技时代如何看待科学

科学在今天已经深入人心,但实际上,究竟该怎么看待科学,还是存在许多争论和不同看法,最主要的分歧在两个方面。一、什么是科学?即科学和非科学之间,到底有没有界限,究竟怎么划分为好?比如,有人提出中医不是科学,有人认为风水也是科学,等等,这些都是有争议的。二、科学的价值或者说作用,到底怎么看?有人热情称赞科学,说它是经济社会发展的主要动力;也有人认为,人类发展进程中的许多问题,包括生态问题、精神危机等,都是科学技术的发展造成的。那么,科学的价值到底是正面的还是负面的?我们对科学的基本态度应当是怎样的?
免疫正常儿童播散型组织胞浆菌病1例报告

组织胞浆菌病是由荚膜组织胞浆菌感染引起的真菌病,该病主要流行于美洲、非洲及亚洲等地区,欧洲少见,我国大陆非本病流行地区,但相关报道近期呈上升趋势。组织胞浆菌病好发于免疫缺陷患者,免疫功能正常人群发病较少。本院收治了1例免疫功能正常的组织胞浆菌病的儿童,现报告如下。
Synthesis, Structure and Thermochromic Properties of a Copper(Ⅱ) Complex Based on Naphthyl Carboxylate and Benzimidazolyl Ligands

One novel copper(II) complex, [Cu(NAA)_2(bim)_2]?H_2O (1, HNAA = a- naphthylacetic acid, bim = benzimidazole) has been synthesized and characterized by X-ray single-crystal diffraction analysis, elemental analysis, and IR spectrum. It crystallizes in monoclinic, space group C2/c with a = 1.15969(12), b = 1.9757(2), c = 1.45763(16) nm, β = 104.712(2)o, V = 3.2298(6) nm~3, Z = 4, C_(38)H_(32)N_4O_5Cu, M_r = 688.22, D_c = 1.418 g/cm~(-3), μ = 0.729 mm~(-1), S = 1.039, F(000) = 1428, the final R = 0.0380 and wR = 0.0912 for 2849 unique reflections. In 1, two carboxylate and two benzimidazole ligands coordinate to the central Cu(II) atom by a bidentate chelate mode. Interesting, reversible thermochromic properties of 1 can be observed and investigated by thermal analysis method.
传统光滑粒子动力学方法的适用性分析

光滑粒子动力学(smoothed particle hydrodynamics,SPH)是一种典型的无网格拉格朗日型数值方法,但它存在计算精度相对较低的缺陷.为调查精度问题的物理本质,将SPH粒子类比于实体物理颗粒,分析了SPH粒子的弹性效应,并提出了一个表征黏弹效应比的无量纲数.通过二维Couette流模拟,考察了该无量纲数对粒子速度剖面与排布方式的影响.研究结果表明,系统的有效黏度随该无量纲数的增大而减小,且粒子数的增加只能显著降低较小无量纲数下的有效黏度.名义黏性耗散、总耗散以及理论耗散之间的差异,进一步验证了弹性效应所导致的非物理耗散.总之,由于马赫数与该无量纲数的限制,SPH模拟存在一个临界雷诺数,只有低于这个临界数,才能基于合适的模型参数实现牛顿流体的精确模拟.
非耕作土~(210)Pb_(ex)含量对侵蚀速率变化的响应模型

在分析非耕作土壤侵蚀速率变化对土壤中~(210)Pb_(ex)含量变化机制的基础上,利用质量平衡模型建立了非耕作土壤侵蚀速率变化对土壤~(210)Pb_(ex)含量变化的响应模型;并针对非耕作土壤~(210)Pb_(ex)示踪土壤侵蚀速率的模型,通过土壤侵蚀速率变化对模型进行数值模拟,结果证明:(1)"~(210)Pb_(ex)法的测定值表征100a或200a以来的平均土壤侵蚀速率"的认识是不正确的;(2)非耕作土壤剖面中~(210)Pb_(ex)面积活度在土壤侵蚀速率发生变化后,随时间推移呈指数变化,且土壤侵蚀速率与~(210)Pb_(ex)含量呈反比例关系;(3)非耕作土壤中~(210)Pb_(ex)含量达到稳定态的时间受土壤侵蚀速率变化量和张弛质量深度影响.研究结果对正确认识~(210)Pb_(ex)法的侵蚀速率测定值的表征时间具有理论指导意义.
帕隆藏布江中坝段河岸沉积ESR测年

河岸阶地的沉积组成序列分析对于认识研究区演化历史意义重大。帕隆藏布江为雅鲁藏布江北侧最大的支流,位于青藏高原东南部,冈底斯-念青唐古拉地质构造区的东端,新构造活跃。受到沿雅鲁藏布江北上西南季风气流的影响,降水丰富,海洋性冰川发育。地质气候条件造就了帕隆藏布的深切峡谷的地貌,并且泥石流、滑坡和溜砂坡等多种山地灾害频发。河谷两岸的巨厚沉积物除了冰碛物、冲洪积物之外,泥石流堆积体、崩滑堆积物、溜砂坡堆积物等随处可见,这些沉积物不仅是历史时期灾害的忠实记录,而且由于较为松散还容易引发新的山地灾害。特别是该段溜砂坡灾害广泛发育,因此,分析这些沉积物的形成时代及其与气候之间的关系,对于认识研究区山地灾害形成机理及其对全球变化的响应具有重要意义。
DRUG AND PLASMID DNA CO-DELIVERY NANOCARRIERS BASED ON ABC-TYPE POLYPEPTIDE HYBRID MIKTOARM STAR COPOLYMERS

We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly(ethylene oxide), poly(L-lysine), and poly(ε-caprolactone) arms, PEO(-b-PLL) -b-PCL, and their functional applications as co-delivery nanocarriers of chemotherapeutic drugs and plasmid DNA. Miktoarm star copolymer precursors, PEO(-b-PZLL)-b-PCL, were synthesized at first via the combination of consecutive "click" reactions and ring-opening polymerizations (ROP), where PZLL is poly(ε-benzyloxycarbonyl-L-lysine). Subsequently, the deprotection of PZLL arm afforded amphiphilic miktoarm star copolymers, PEO(-b-PLL)-b-PCL. In aqueous media at pH7.4, PEO(-b-PLL)-b-PCL self-assembles into micelles consisting of PCL cores and hydrophilic PEO/PLL hybrid coronas. The hydrophobic micellar cores can effectively encapsulate model hydrophobic anticancer drug, paclitaxel; whereas positively charged PLL arms within mixed micellar corona are capable of forming electrostatic polyplexes with negatively charged plasmid DNA (pDNA) at N/P ratios higher than ca. 2. Thus, PEO(-b-PLL)-b-PCL micelles can act as co-delivery nanovehicles for both chemotherapeutic drugs and genes. Furthermore, polyplexes of pDNA with paclitaxel-loaded PEO(-b-PLL)-b-PCL micelles exhibited improved transfection efficiency compared to that of pDNA/blank micelles. We expect that the reported strategy of varying chain topologies for the fabrication of co-delivery polymeric nanocarriers can be further applied to integrate with other advantageous functions such as targeting, imaging, and diagnostics.
一种新型医用激光抽吸废烟气灯罩的设计

激光治疗时产生大量的烟雾,传统的防护措施抽吸废烟气效果差、影响手术视野、浪费人力。设计了一种激光治疗中抽吸废烟气、照明和便于操作、移动的适用于激光治疗的抽吸废烟气灯罩,可达到充分抽吸废烟气、保证激光操作视野清晰、并节省人力的目的,具有很高的推广价值。
台风重力波的谱结构和动量通量特征分析

利用中尺度预报模式WRF针对2005年台风"麦莎"开展的数值模拟结果显示,在台风活动期间,其上空以台风为中心的区域中,持续地出现了显著平流层重力波。在此基础上,本文利用该数值模拟的数据进一步对台风诱发的平流层重力波进行谱结构分析和动量通量估计。结果显示:重力波谱结构呈明显的单峰窄谱结构,主要的波动具有1000km左右的水平尺度、12~18h的时间尺度、垂直波长大约为7~9km。这种单峰窄谱的谱结构与以往已研究的孤立对流单体等深对流系统所诱发的重力波谱结构特征并不相同。另外,功率谱和动量通量谱分量集中分布在水平波数大于零的部分(k_h>0),这种不对称的分布反映了重力波的传播受平均流调控,逆背景流传播。分析结果还表明,与台风相关的平流层重力波具有相当大的动量通量,在20km高度位置上估计得到的净纬向动量通量为0.7845×10~(-3)Pa,该值约为驱动QBO现象所需的波动动量通量的26%。
中期模式扰动风在2010年区域暴雨预报中的天气学释用

观测和中期模式预报的大气风场可以物理分解为气候风场、行星尺度瞬时扰动风场和天气尺度瞬时扰动风场。本文用欧洲中期天气预报中心(ECMWF)模式和美国全球预报系统(GFS)模式输出的850hPa风场进行天气尺度瞬时扰动风的分解,发现中国大陆暴雨带多位于扰动风的辐合线上。用2010年发生在中国大陆的主要区域性暴雨做分析,ECMWF预报产品分解的850hPa扰动风辐合线提前3,6和9天指示暴雨带的正确率分别是100%,85%和15%,而GFS预报产品分解的正确率分别为53%,15%和6%。欧洲模式直接预报区域暴雨的平均提前有效时间为3.1天,而模式预报产品分解的扰动风辐合系统指示区域暴雨的平均提前有效时间为6.7天。
过量尿嘧啶胁迫下pyrG对维持构巢曲霉胞内尿嘧啶稳定及正常产孢起关键作用

为减少DNA中尿嘧啶的掺入,细胞内尿嘧啶水平受到严格控制,但其机制尚不清楚.构巢曲霉(Aspergillus nidulans)乳清酸核苷5'-磷酸脱羧酶PyrG催化乳清苷酸(OMP)转化为尿苷酸(UMP)的反应,本研究发现,在过量尿嘧啶存在的情况下,PyrG对维持细胞内较低尿嘧啶浓度具有重要作用.与野生菌株相比,过量尿嘧啶及其代谢物对乳清苷酸脱羧酶缺陷的pyrG89突变体具有更强的抑制作用,并能增强pyrG89突变体的有性发育.通过数字基因表达谱(DGE)分析pyrG89突变体和野生菌株对过量尿嘧啶的转录响应,发现尿嘧啶转录激活pyrG89突变体中有性发育相关的基因.HPLC定量分析显示,在过量尿嘧啶存在的情况下,pyrG89突变体胞内尿嘧啶水平是野生菌株的6.5倍.本研究的结果不仅为细胞内尿嘧啶循环及细胞对过量尿嘧啶的适应机制提供了新内容,还揭示了OMP脱羧酶对真菌生长发育存在潜在影响.
塔里木盆地天然气中汞含量与分布特征

结合塔里木盆地天然气成因类型、烃源岩沉积环境、构造活动以及储层特征,对19个主要油气田(藏)41口井天然气中汞含量与分布特征进行了分析。库车坳陷汞含量为15.0~56964.3ng/m~3,平均值为11793.7ng/m~3,塔北隆起为16.1~28108.8ng/m~3,平均值为6725.8ng/m~3,北部坳陷为17.7~3339.5ng/m~3,平均值为1678.6ng/m~3,中央隆起为14.2~20220.6ng/m~3,平均值为4311.1ng/m~3,而塔西南坳陷为15428.5~296763.0ng/m~3,平均值为156095.7ng/m~3.塔里木盆地各构造单元的天然气中汞含量具有明显的区域性不同,塔西南构造活动强烈地带天然气中含量异常。自生自储型和火山活动期天然气藏有利于汞富集,而次生油气藏中汞含量明显偏低。陆相沉积环境形成的煤型气中汞含量高于海相沉积形成的油型气。因此,塔里木盆地天然气中汞含量主要与天然气成因类型、沉积环境、构造活动和火山活动有关,其中构造活动为主要控制因素,其次为沉积环境和火山活动。
塔里木板块西南缘新元古代沉积相和冰期划分

通过对塔里木板块西南缘叶城地区南华系-埃迪卡拉系地层沉积相的划分和化学蚀变指数(CIA)分析,讨论南华系所记录的冰期特征。研究区南华系-埃迪卡拉系地层可划分出6个沉积相:山麓冲积扇相、湖泊相、冰成相、滨海相、浅海相以及泻湖相,该地区经历了一个由陆向海的演变过程,并以滨浅海相沉积为主。通过CIA值特征分析确立了研究区南华纪经历了2次明显的寒冷气候,可分别称为波龙冰期和雨塘冰期,表现为波龙组厚层冰碛岩和雨塘组较薄层冰碛岩沉积。波龙组冰期可能相当于库鲁克塔格地区特瑞艾肯冰期、阿克苏地区的尤尔美那克冰期和华南地区的南沱冰期,也即相当于全球性的Marinoan冰期,而雨塘组冰期可能相当于库鲁克塔格地区的汉格尔乔克冰期,即相当于纽芬兰地区的Gaskiers冰期。
1977~2008年中国森林生物量碳汇的时空变化

森林在区域和全球碳循环中起着关键作用.研究中国森林生物量碳源汇变化对于估算区域碳收支和制定应对气候变化的森林管理政策有重要意义.利用1977~2008年间6期的森林资源清查资料,通过评估生物量碳库变化来估算中国森林生物量碳汇大小及其变化.森林按其用途和形态特征,分为林分、经济林和竹林三大类别.采用连续生物量转换因子法估算林分生物量碳库,平均生物量法估算经济林和竹林生物量碳库.结果显示,在1977~2008年间,中国森林生物量碳库累计增加(即生物量碳汇)1896 TgC(1 Tg=10~(12)g),其中,林分、经济林和竹林分别增加1710,108和78 TgC;年均生物量碳汇为70.2 TgC/a,相当于抵消中国同期化石燃料排放CO_2的7.8%.研究还表明,中国人工林的生物量碳库持续增加,生物量碳汇为818 TgC,占林分总碳汇的47.8%;各龄级林分的生物量碳汇都有不同程度的增加:老龄林、中龄林和幼龄林分别增加930,391和388 TgC.由于现阶段中国森林具有林龄小、平均碳密度低和人工林面积大的特点,因此未来中国森林生物量增汇潜力巨大.
益气祛瘀化痰法对冠心病左室舒张功能的影响

目的观察益气祛瘀化痰法对冠心病患者左室舒张功能的影响。方法选择住院及门诊中医辨证为气虚痰瘀型的左室舒张功能不全冠心病患者42例,随机分为观察组和对照组,每组21例。对照组采用冠心病西医标准治疗,观察组在对照组的基础上加服益气祛瘀化痰方药,比较两组在服药12周后E 峰、A 峰、E/A、左房内径(LAD) 、E 波减速时间(DT) 、左室等容舒张时间(IVRT) 、室间隔舒张末期厚度(IVSd)及左室后壁舒张末期厚度(LVPWTd)等左室舒张功能指标的变化。结果观察组各项指标较治疗前均有明显改善,差异有统计学意义(P< 0.05),观察组E峰、A峰、E/A、LAD、DT、IVRT改善明显优于对照组,差异有统计学意义(P < 0. 05) 。两组IVSd、LVPWTd 的改善差异也有统计学意义(P < 0. 05),观察组治疗效果较对照组更为显著(P < 0. 05) 。结论在西医基础治疗基础上加用益气祛瘀化痰法,能够明显改善冠心病患者左室舒张功能。
阻塞性睡眠呼吸暂停低通气综合征及过度嗜睡与交通事故的关系

目的调查阻塞性睡眠呼吸暂停低通气综合征(OSAHS)、过度嗜睡在客车司机中的流行情况,以及与交通事故的关系。方法应用整群抽样方法对承德市长途客车站449名客车司机进行问卷调查,对中重度打鼾客车司机进行随机抽样并行简易睡眠监测。结果在449名司机中,OSAHS的患病率为9.9%,55名(12.2%)ESS评分≥9分,57名(12.7%)曾经每年至少1次在开车时嗜睡,19名(4.2%)曾经明确因为在开车时嗜睡而发生交通事故,13名(2.9%)因为嗜睡而发生未遂交通事故,有过度嗜睡习惯的司机发生交通事故的风险是无过度嗜睡习惯司机的4.22倍(OR=4.22,95%CI 2.25~7.91,P<0.01),中重度打鼾司机发生交通事故的风险是无打鼾司机的5.29倍(OR=5.29,95%CI 2.495~9.507,P<0.01)。结论职业司机中OSAHS的患病率较高。过度嗜睡、中重度打鼾也是导致交通事故的一个重要原因。应重视司机嗜睡情况并尽早诊断和治疗患有OSAHS的司机。
生姜提取物对阿尔茨海默病大鼠动物炎症因子的影响

目的研究生姜提取物(ginger root extract)对β淀粉样蛋白(β-amyloid protein beta,Aβ)所致阿尔茨海默病(Alzheirner’s disease,AD)大鼠大脑海马区内核因子κB(NF-κB)及白细胞介素-1β(IL-1β)的表达及相互关系的影响,进一步探讨生姜提取物对AD的可能治疗作用及机制。方法 SD健康大鼠60只,雌雄各半,随机分成假手术(SOP)组和手术(OP)组,分别为10只和50只,SOP组侧脑室注射生理盐水,OP组侧脑室注射Aβ25~35。造模成功后,再将OP组随机分成生姜提取物低剂量组(OP+LGRE组)、生姜提取物中剂量组(OP+MGRE组)、生姜提取物高剂量组(OP+HGRE组)、石杉碱甲组(OP+HPA组)及空白对照组(OP+BC组)。各组大鼠予灌胃相应药物(OP+BC组予等量生理盐水)4周后,以NF-κB、IL-1β免疫组化染色比较大鼠大脑炎症系统指标及病理的变化。结果 OP+HGRE组、OP+HPA组NF-κB、IL-1β的阳性表达活性明显升高;在OP+LGRE组、OP+MGRE组干预效果不显著。结论生姜提取物在高剂量时对AD大鼠具有提高NF-κB、IL-1β阳性表达活性的作用。
二甲双胍调节内皮细胞组织因子途径抑制物的表达

组织因子途径抑制物(tissue factor pathway inhibitor,TF-PI)高表达于血管内皮细胞表面,特异性抑制外源性凝血途径,是一种控制凝血启动的抗凝蛋白。血栓形成是糖尿病的主要并发症之一。糖尿病患者血糖持续升高,导致糖基化终末产物(advanced glycosylation end products,AGEs)的生成。AGEs水平可上调组织因子,促进血栓形成。作为控制糖尿病的一线用药,二甲双胍明显缓解糖尿病并发症,但目前尚无其调节糖尿病血栓及TFPI表达的报道。本研究检测了二甲双胍对TFPI表达的影响,并初步探讨了其中机制,为糖尿病血栓的干预提供了新的靶点。
风引汤临证应用体会

探索风引汤的理论研究与临床应用,重点诠释用药要点、剖析方药配伍、探讨用量比例,权衡病证如热、瘫、痫,并应用风引汤辨治高血压病、帕金森病、敌敌畏农药中毒后遗症所致肢体强直等。认为风引汤是《伤寒杂病论》中辨治肝热生风证的重要代表方,具有良好的治疗作用,且运用风引汤不能局限于症状表现,只要审明病变证机是肝热生风即可以法选用。
从“脾虚络阻毒损”认识胃癌前病变胃黏膜屏障损伤及其辨治思路

胃黏膜屏障功能在胃癌前病变(PLGC)的发生、发展中起着重要作用。胃黏膜屏障的损伤修复与胃黏膜上皮细胞的凋亡增殖失衡及各种神经介质和体液调节关系密切,胃黏膜屏障损伤程度又与PLGC的发展趋势密切相关。"脾虚络阻毒损"是PLGC胃黏膜屏障损伤的基本病机特征。其中脾胃虚弱是PLGC胃黏膜屏障损伤的发病基础,胃络瘀阻、毒损胃络是贯穿PLGC胃黏膜屏障损伤的关键病理因素。健脾通络解毒法是PLGC胃黏膜屏障损伤修复保护的重要辨治方法。
去皮晒干对北沙参挥发油成分的影响

目的比较直接晒干与去皮晒干北沙参挥发油成分差异,为确定合理的产地加工方法提供参考。方法采集北沙参植株根部,分别直接晒干和烫后去皮晒干,以水蒸气蒸馏法提取挥发油,采用Agilent7890A-5973N型气相-质谱联用仪进行分析。结果直接晒干与去皮晒干北沙参挥发油成分具有明显差异,直接晒干北沙参挥发油以萜类和醛酮类化合物为主,去皮晒干北沙参挥发油中的萜类化合物相对含有量显著降低,直接晒干能够保留种类更多的化合物。结论直接晒干较去皮晒干更能保证北沙参药材质量。
梓醇药理作用的研究进展

梓醇是中药材地黄的有效成分,现代研究证明其具有广泛的药理学作用。本文检索近年来有关梓醇药理作用的文献,对其药理学研究现状加以归纳总结,为梓醇的开发和利用提供参考。
HPLC-UV法同时测定六味地黄制剂中丹皮酚与熊果酸

目的建立同时检测六味地黄丸制剂中熊果酸和丹皮酚的HPLC-UV方法。方法取市售不同厂家的六味地黄制剂,采取甲醇超声提取,以HPLC-UV法测定其产品中熊果酸和丹皮酚。实验采用kromasil C_(18)(200 mm×4.6 mm,5μm)色谱柱,以50%甲醇/乙腈(A)-0.1%磷酸(B)为流动相,梯度洗脱,体积流量0.8 mL/min,检测波长215 nm。结果熊果酸和丹皮酚分别在2.40~37.5μg/mL和0.22~3.38μg/mL的质量浓度范围内与峰面积呈良好的线性关系,回归方程分别为Y=244.31X-390.32(R=0.990 3)和Y=2 217X-784.42(R=0.998 4)。结论该方法可以使样品中的熊果酸、丹皮酚与其他色谱峰有效分离,方法简便、准确,重复性好,结果可为评价不同厂家生产的六味地黄丸制剂一致性提供依据。
Box-Behnken响应面法优化黄芩素微丸的缓释包衣处方

目的制备黄芩素缓释包衣微丸,优化处方。方法以增塑剂(柠檬酸三乙酯)质量分数、丙烯酸树脂聚合物比例(Eudragit RSEudragit RL)、以及包衣增重为考察因素,建立了3因素3水平的Box-Behnken实验设计,以微丸在2、6、12 h时的释放度为响应值。根据Box-Behnken响应面优化法,建立了考察因素和响应值之间的关系。结果优化试验得到最优处方为增塑剂11%,聚合物比例4∶1,包衣增重12%,其在2、6、12 h时的释放度预测值分别为28.34%、58.56%和95.00%,根据优化处方制得缓释微丸释放度实测值与预测值基本一直。结论Box-Behnken响应面法优化法可有效应用于黄芩素微丸的缓释包衣处方的筛选和优化。
调味品中嘌呤类物质高效液相色谱法检测

嘌呤是构成核苷酸的重要碱基,代谢终产物是尿酸,代谢紊乱使尿酸的生成增加或排出减少,引起高尿酸血症及痛风。饮食摄入的嘌呤可影响血清中尿酸水平。随着居民对食品风味的追求,复合调味品在烹饪中的使用率逐渐增加。这些复合调味品均添加有呈味核苷酸5’-肌苷酸二钠盐(ino-sine monophosphae,IMP,又称次黄苷酸)和5’-鸟苷酸二钠盐(guanosine monophosphate,GMP)。这2种核苷酸可代谢生成次黄嘌呤和鸟嘌呤,是通过食物摄入嘌呤的来源之一。本研究利用高效液相色谱法对鸡精、鸡粉、高汤精、蔬之鲜等复合调味料的嘌呤含量进行测定,并对其嘌呤含量进行比较。
广西低档暗娼艾滋病知识及行为状况调查

随着艾滋病疫情的发展,经性途径传播作为中国艾滋病流行的主要传播方式仍在进一步上升。在报告的疫情中,经性途径传播的比例从2006年的33.1%上升到2011年1—9月的75.2%。相关研究显示,暗娼是传播艾滋病的重要"桥梁人群"。暗娼人群由于其性行为频繁,极易造成性病和艾滋病的传播,而处于底层的低档暗娼,因其流动性大、隐蔽性强,在一定程度上更容易受到艾滋病病毒(human immunodeficiency virus,HIV)的侵袭,是艾滋病防治的重要目标人群。为了解广西低档暗娼人群艾滋病知识、行为及HIV 感染状况,为制定有效干预措施提供科学依据,于2011年9—10月对广西14个市和69个县的7 936名低档暗娼进行问卷调查和HIV 抗体、丙型肝炎病毒(hepatitis C virus,HCV)抗体、梅毒抗体检测。现将结果报告如下。
骨科弹道式冲击波配合前臂伸肌群本体感觉神经肌肉促进训练治疗顽固性网球肘40例报道

网球肘是骨科和运动创伤科常见劳损性疾病,临床上常采取封闭、电针、理疗等方法治疗,但患者症状常易复发,影响日常生活质量,尤其是病程较长或病情反复发作的顽固性网球肘,治疗更为棘手。近年来,骨科弹道式冲击波和本体感觉神经肌肉促进法(proprioceptive neuromuscular facilitation,PNF)作为治疗软组织劳损性疾病的新方法得到了广泛应用,疗效肯定。本研究采取骨科弹道式冲击波配合前臂伸肌群PNF训练治疗顽固性网球肘,临床疗效较好,现总结报道如下。
耐碱性木聚糖酶

造纸工业是我国国民经济中具有可持续发展特点的重要产业,也是我国重要的工业污染源之一。近年来,世界范围内的造纸工业都受到资源、环境和效益等多方面的约束,都力求寻找能够达到节能减耗、保护生态环境、提高生产效率和经济效益及产品质量的先进生产技术。木聚糖酶及其潜在的工业应用前景引起人们关注,低(无)纤维素酶活性的木聚糖酶尤其有着诱人的应用前景,它可以应用于生物制浆、纸浆漂白、废纸二次纤维回收、废纸脱墨处理、纸浆纤维改性剂和纺织工业等,特别是其在纸浆漂白工艺中的巨大应用潜力,已成为各界同行的研究热点。应用于生物漂白过程中的木聚糖酶必须满足没有或者只有少量纤维素酶伴随产生,具有良好的耐碱性及耐高温性,在纸浆中具有稳定的酶活性等条件。自然界中微生物产生的木聚糖降解酶系比较复杂,许多会伴随纤维素酶的产生,这些酶的性质相近,不易分离纯化。此外,除了一些生长在极端环境中的微生物如嗜热菌、嗜碱菌等分泌的木聚糖酶能够满足生物漂白的要求之外,大多数来源于真菌、细菌或放线菌的木聚糖酶都需要在应用过程中调节反应条件。以上这些限制条件严重阻碍了木聚糖酶规模化生产及应用工艺的建立。
GOMA:functional enrichment analysis tool based on GO modules

Analyzing the function of gene sets is a critical step in interpreting the results of high-throughput experiments in systems biology. A variety of enrichment analysis tools have been developed in recent years, but most output a long list of significantly enriched terms that are often redundant, making it difficult to extract the most meaningful functions. In this paper, we present GOMA, a novel enrichment analysis method based on the new concept of enriched functional Gene Ontology (GO) modules. With this method, we systematically revealed functional GO modules, i.e., groups of functionally similar GO terms, via an optimization model and then ranked them by enrichment scores. Our new method simplifies enrichment analysis results by reducing redundancy, thereby preventing inconsistent enrichment results among functionally similar terms and providing more biologically meaningful results.
The genetics and biology of KRAS in lung cancer

Mutational activation of KRAS is a common oncogenic event in lung cancer and other epithelial cancer types.Efforts to develop therapies that counteract the oncogenic effects of mutant KRAS have been largely unsuccessful,and cancers driven by mutant KRAS remain among the most refractory to available treatments.Studies undertaken over the past decades have produced a wealth of information regarding the clinical relevance of KRAS mutations in lung cancer.Mutant Kras-driven mouse models of cancer,together with cellular and molecular studies,have provided a deeper appreciation for the complex functions of KRAS in tumorigenesis.However,a much more thorough understanding of these complexities is needed before clinically effective therapies targeting mutant KRAS-driven cancers can be achieved.
精神分裂症认知损害和临床症状与脑白质关系的研究进展

神经病理学、神经遗传学和神经影像学均显示精神分裂症发生与白质有一定的关系。大量研究报道了精神分裂症脑白质存在异常。白质对不同的脑区进行连接、传递信息,研究表明不单是特定脑区内的异常,而且不同脑区的连接异常导致了该病临床症状和认知功能的障碍。由此,负责连接远端或近端脑区的白质纤维束越来越引起研究者的兴趣。弥散张量成像(diffusion tensor imaging,DTI)研究方法,克服了传统的MRI技术对纤维束方向和结构的不敏感性,可以对活体脑白质纤维束的结构和完整性进行评价,为进一步研究精神分裂症的病理生理学机制提供了新的方法。目前,DTI研究精神分裂症白质异常比较一致的发现包括弓状束和内囊前肢。对精神分裂症白质DTI与认知和临床症状的相关性研究还比较少。本文主要从这两方面对报道的相关文献进行综述。