检索结果-南通市图书馆

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

光动力学疗法剂量学的研究进展

生物化学与生物物理进展 2009年第6期36卷 676-683页

作者：李步洪谢树森 HUANG Zheng WILSON brian c 福建师范大学医学光电科学与技术教育部重点实验室福建省光子技术重点实验室福州350007 Department of Radiation Oncology University of Colorado Denver Colorado 80045 USA Division of Biophysics and Bioimaging Ontario Cancer Institute and Department of Medical Biophysics University of Toronto 610 University Avenue Toronto M5G 2M9 Canada

随着光动力学疗法(photodynamic therapy,PDT)基础研究的不断深入和临床应用的广泛开展,如何精确量化光动力剂量,并根据患者的个体差异进行剂量的实时调整和优化已成为亟待解决的挑战性难题,属PDT研究的前沿热点.综述了现有PDT剂量学研... 详细信息

随着光动力学疗法(photodynamic therapy,PDT)基础研究的不断深入和临床应用的广泛开展,如何精确量化光动力剂量,并根据患者的个体差异进行剂量的实时调整和优化已成为亟待解决的挑战性难题,属PDT研究的前沿热点.综述了现有PDT剂量学研究方法及其相应检测技术的研究进展,其中包括:a.测定光通量密度、光敏剂浓度和氧分压;b.测量光敏剂的光漂白速率和光致产物;c.监测PDT前后组织的光生物学响应;d.检测单态氧在1270nm的近红外发光.同时,还分析了这些PDT剂量学方法的优点和局限性.最后,讨论了PDT剂量学研究中所面临的挑战.

关键词：光动力学疗法剂量学光敏剂光通量密度氧光漂白单态氧

Evaluation of maize inbred lines and topcross progeny for resistance to pre-harvest aflatoxin contamination

在线全文

学校读者我要写书评

暂无评论

The crop Journal 2019年第1期7卷 118-125页

作者： Jake c.Fountain Hamed K.Abbas brian T.Scully Hong Li Robert D.Lee Robert c.Kemerait Baozhu Guo USDA-ARS crop Protection and Management Research Unit Department of Plant Pathology University of Georgia USDA-ARS Biological control of Pests Research Unit USDA-ARS National Horticultural Research Laboratory Shanxi Academy of Agricultural Sciences Millet Research Institute Department of crop and Soil Sciences University of Georgia

Pre-harvest aflatoxin contamination occurs in maize following kernel colonization by Aspergillus flavus. Aflatoxin contamination resistance is a highly desired trait in maize breeding *** identification of novel sources of resistance to pre-harvest aflatoxin contamination is a major focus in germplasm screening efforts. Here, we performed a field evaluation of 64 inbred lines over two years for pre-harvest aflatoxin contamination. Topcrosses were also performed with two testers, B73 and Mo17, to generate 128 F1 hybrids which were also evaluated over two years. Hybrid performance was used to calculate both general combining ability(GcA) of the inbreds, and observed heterosis for aflatoxin resistance. Over both years of the study, aflatoxin concentrations ranged from 80 ± 47 to 17,617 ± 8816 μg kg^(-1) for inbreds, and from 58 ± 39 to 2771 ± 780 μg kg^(-1) for hybrids with significant variation between years and lines. The inbred lines cML52, cML69, cML247, GT-603, GEMS-0005, Hi63, Hp301, and M37 W showed ccumulation in both years of the study and less than the resistant check, Mp313 E, in at least one season. Among these, cML52, GT-603, and Hi63 also showed significant GcA with the testers in hybrid progeny. cML52, GT-603, and M37 W also showed heterotic effects of-13.64%,-12.47%, and-24.50%, respectively, with B73 resulting in reduced aflatoxin contamination. GT-603 also showed a similar heterotic effect for aflatoxin contamination,-13.11%, with Mo17 indicating that this line may serve as a versatile source of aflatoxin contamination resistance in breeding programs.

关键词： Aspergillus flavus Pre-harvest Aflatoxin Maize Topcross

Log-behavior of Two Sequences Related to the Elliptic Integrals

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2020年第3期36卷 590-602页

作者： brian Yi SUN James Jing-Yu ZHAO Department of Mathematics and System Science Xinjiang UniversityUrumqi 830046China School of Mathematics Tianjin UniversityTianjin 300350China

Two interesting sequences arose in the study of the series expansions of the complete elliptic integrals,which are called the catalan-Larcombe-French sequence{Pn}n≥0 and the Fennessey-Larcombe-French sequence{Vn}n≥0 *** this paper,we first establish some criteria for determining log-behavior of a sequence based on its three-term *** we prove the log-convexity of{Vn^2-V(n-1)V(n+1)}n≥2 and{n!Vn}n≥1,the ratio log-concavity of{Pn}n≥0 and the sequence{An}n≥0 of Apéry numbers,and the ratio log-convexity of{Vn}n≥1.

关键词： the catalan-Larcombe-French sequence the Fennessey-Larcombe-French sequence Apéry numbers log-concave log-convex three-term recurrence

Sorption and Leaching Potential of Isoproturon and Atrazine in Low Organic carbon Soil of Pakistan Under a Wheat-Maize Rotation

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2016年第5期26卷 687-698页

作者： Muhammad TAHIR Anwar Ul HASSAN Saliha MAQBOOL brian BARBER William c.KOSKINEN PENG Xinhua David J.MULLA State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) Institute of Soil&Environmental Sciences University of Agriculture FaisalabadPunjab 38000(Pakistan) Soil and Water Management Research Laboratory St.Paul MN 55108-6089(USA) Department of Soil Water&ClimateUniversity of MinnesotaTwin Cities MN 55108-6089(USA)

Pesticide leaching is a great threat in low organic carbon soils when subjected to improper irrigation *** data are available on the sorption and leaching potential of pesticides in agricultural soils of Pakistan with low soil organic carbon(SOc).Lysimeter and field studies were conducted with and without manure application at two irrigation levels in a wheat-fallowmaize rotation in Faisalabad,Punjab,*** was applied to wheat 55 d after sowing at 1 kg active ingredient(a.i.)ha^(-1),while atrazine was sprayed on maize 30 d after sowing at 0.774 kg ***^(-1).Soil was sampled from three depths(0-35,35-70,and 70-110 cm) for the field study and four depths(0-35,35-70,70-115,and 115-160 cm) for the lysimeter study,280 and 65 d after application of isoproturon and atrazine,*** soil-water partition coefficients(K_d) of isoproturon and atrazine ranged from 0.3 to 1.2 and 0.4 to 1.5 L kg^(-1),respectively,and increased linearly with increase in SOc *** organic carbon-normalized soil-water partition coefficient(K_(oc)) of isoproturon and atrazine averaged 246.1 and 184.9 L kg^(-1),respectively,being higher with low spiking *** residues measured 280 d after application ranged from 2.1% to 3.6% of the applied mass in the lysimeter study and from 1.5% to 3.1% under field *** residues 65 d after application ranged from only 0.62% to 0.78% and from 0.88% to 0.82% in the lysimeter and field studies,*** lowest levels of residues for both pesticides were observed with frequent irrigation applied to manure-amended soil.A pesticide leaching risk screening tool,the ground water ubiquity score(GUS),indicated that in the absence of manure under both irrigation levels,isoproturon has a leaching potential(GUS = 2.8),while with the application of manure it has a very low leaching *** GUS ranged from 1.7 to 1.9,indicating a very low risk of leaching.

关键词： concentration dependent sorption irrigation manure leaching risk assessment pesticide

Anatomy of a eustatic event during the Turonian (Late cretaceous) hot greenhouse climate

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2017年第1期60卷 20-29页

作者： Bilal U. HAQ brian T. HUBER Department of Paleobiology MRC-121Smithsonian InstitutionWashington D C 20013USA Sorbonne ISTEP Pierre&Marie Curie UniversityParis 75005France

Sequence stratigraphic studies consider relative change in sea level(as regulated by eustasy,local tectonics and sediment supply)as the main builder of the stratigraphic *** has generally been considered as a consequence of the growth and decay of continental ice sheets that would explain large,rapid changes in sea level,even during periods of relative global climatic ***,such a mechanism has become increasingly difficult to envision during times of extreme global warmth such as the Turonian,when the equator-to-pole temperature gradient was very low and the presence of polar ice seems *** paper investigates the timing and extent of sea level falls during the late cenomanian through Turonian,especially the largest of those events,sequence boundary KTu4,which occurred during the middle to late Turonian peak of the cretaceous hot greenhouse *** conclude that the amplitude of the widespread third-order sea level fall in the middle Turonian that is centered at^91.8 Ma varies at different locations depending on the influence of dynamic topography on local tectonics and regional climatic *** volume variations seem unlikely as a mechanism for controlling sea level at this ***,this causal factor cannot be ruled out completely since Antarctic highlands(if they existed in the Late cretaceous)could sequester enough water as ice to cause eustatic *** ascertain this requires detailed tomographic imaging of Antarctica,followed by geodynamic modeling,to determine whether high plateaus could have existed to accumulate ephemeral ice *** mechanisms for sea level change,such as transference between ground water(a small amplitude shorter time scale effect)and the ocean and entrainment and release of water from the mantle to the oceanic reservoir(a potentially large amplitude and longer time scale process),are intriguing and need to be explored further to prove their efficacy at third-order time scales.

关键词： Eustatic event Turonian Hot greenhouse climate

Osteoblast-restricted Disruption of the Growth Hormone Receptor in Mice Results in Sexually Dimorphic Skeletal Phenotypes

在线全文

学校读者我要写书评

暂无评论

Bone Research 2013年第1期1卷 85-97页

作者： Vandana Singhal brian c.Goh Mary L.Bouxsein Marie-claude Faugere Douglas J.DiGirolamo Department of Orthopaedic Surgery Johns Hopkins University School of MedicineBaltimoreMDUSA center for Advanced Orthopedic Studies Beth Israel Deaconess Medical Center and Harvard Medical SchoolBostonMAUSA Albert B.chandler Medical center University of KentuckyLexingtonKYUSA

Growth hormone （GH） exerts profound anabolic actions during postnatal skeletal development, in part, through stimulating the production of insulin-like growth factor-1 （IGF-1） in liver and skeletal tissues. To examine the requirement for the GH receptor （GHR） in osteoblast function in bone, we used cre-LoxP methods to disrupt the GHR from osteoblasts, both in vitro and in vivo. Disruption of GHR from primary calvarial osteoblasts in vitro abolished GH-induced signaling, as assessed by JAK2/STAT5 phosphorylation, and abrogated GH-induced proliferative and anti-apoptotic actions. Osteoblasts lacking GHR exhibited reduced IGF-l-induced Erk and Akt phosphorylation and attenuated IGF-1-induced proliferation and anti-apoptotic action. In addition, differentiation was modestly impaired in osteoblasts lacking GHR, as demonstrated by reduced alkaline phosphatase staining and calcium deposition. In order to determine the requirement for the GHR in bone in vivo, we generated mice lacking the GHR specifically in osteoblasts （△GHR）, which were born at the expected Mendelian frequency, had a normal life span and were of normal size. Three week-old, female AGHR mice had significantly reduced osteoblast numbers, consistent with the in vitro data. By six weeks of age however, female AGHR mice demonstrated a marked increase in osteoblasts, although mineralization was impaired; a phenotype similar to that observed previously in mice lacking IGF-1R specifically in osteoblasts. The most striking phenotype occurred in male mice however, where disruption of the GHR from osteoblasts resulted in a ＂feminization＂ of bone geometry in 16 week-old mice, as observed by facT. These results demonstrate that the GHR is required for normal postnatal bone development in both sexes. GH appears to serve a primary function in modulating local IGF-1 action. However, the changes in bone geometry observed in male AGHR mice suggest that, in addition to facilitating IGF-1 action, GH may function to a greater

关键词： growth hormone osteoblasts knockout mice bone sexual dimorphism

The disruption of protein-protein interactions with co-chaperones and client substrates as a strategy towards Hsp90 inhibition

在线全文

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2021年第6期11卷 1446-1468页

作者： Michael A.Serwetnyk brian S.J.Blagg Department of chemistry and Biochemistry Warren Family Research Center for Drug Discovery and DevelopmentUniversity of Notre DameIN 46556USA

The 90-kilo Dalton(kD) heat shock protein(Hsp90) is a ubiquitous,ATP-dependent molecular chaperone whose primary function is to ensure the proper folding of several hundred client protein *** many of these clients are overexpressed or become mutated during cancer progression,Hsp90 inhibition has been pursued as a potential strategy for cancer as one can target multiple oncoproteins and signaling pathways *** first discovered Hsp90 inhibitors,geldanamycin and radicicol,function by competitively binding to Hsp90’s N-terminal binding site and inhibiting its ATPase ***,most of these N-terminal inhibitors exhibited detrimental activities during clinical evaluation due to induction of the pro-survival heat shock response as well as poor selectivity amongst the four ***,alternative approaches to Hsp90 inhibition have been pursued and include c-terminal inhibition,isoform-selective inhibition,and the disruption of Hsp90 protein-protein *** the Hsp90 protein folding cycle requires the assembly of Hsp90 into a large heteroprotein complex,along with various co-chaperones and immunophilins,the development of small molecules that prevent assembly of the complex offers an alternative method of Hsp90 inhibition.

关键词： Hsp90 Protein-protein interactions Disruptors Natural products Small molecules Peptidomimetics

在线全文

学校读者我要写书评

暂无评论

Python cookbook

Historical review of the causes of cancer

作者： (美)David Beazley，(美)brian K. jones

来源：南通市图书馆图书评论

学校读者我要写书评

暂无评论

World Journal of clinical Oncology 2016年第1期7卷 54-86页

作者： clarke brian Blackadar Department of Food Science Ontario Agricultural College University of Guelph

In the early 1900 s, numerous seminal publications reported that high rates of cancer occurred in certain occupations. During this period, work with infectious agents produced only meager results which seemed irrelevant to humans. Then in the 1980 s ground breaking evidence began to emerge that a variety of viruses also cause cancer in humans. There is now sufficient evidence of carcinogenicity in humans for human T-cell lymphotrophic virus, human immunodeficiency virus, hepatitis B virus, hepatitis c virus, human papillomavirus, Epstein-Barr virus, and human herpes virus 8 according to the International Agency for Research on cancer(IARc). Many other causes of cancer have also been identified by the IARc, which include: Sunlight, tobacco, pharmaceuticals, hormones, alcohol, parasites, fungi, bacteria, salted fish, wood dust, and herbs. The World cancer Research Fund and the American Institute for cancer Research have determined additional causes of cancer, which include beta carotene, red meat, processed meats, low fibre diets, not breast feeding, obesity, increased adult height and sedentary lifestyles. In brief, a historical review of the discoveries of the causes of human cancer is presented with extended discussions of the difficulties encountered in identifying viral causes of cancer.

关键词： Infections causes cancer carcinogens Historical Etiology International agency for research on cancer