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Oxidative stress and male reproductive health

Asian j.urnal of Andrology 2014年第1期16卷 31-38页

作者： Robert j.Aitken Tegan B Smith Matthew S j.bling mark A Baker Geoffry N De Iuliis Priority Research Centre in Reproductive Science Discipline of Biological Sciences Faculty of Science and IT University of Newcastle Callaghan NSW 2308 Australia

One of the maj.r causes of defective sperm function is oxidative stress, which not only disrupts the integrity of sperm DNA but also limits the fertilizing potential of these cells as a result of collateral damage to proteins and lipids in the sperm plasma membrane. The origins of such oxidative stress appear to involve the sperm mitochondria, which have a tendency to generate high leve｜s of superoxide anion as a prelude to entering the intrinsic apoptotic cascade. Unfortunately, these cells have very little capacity to respond to such an attack because they only possess the first enzyme in the base excision repair （BER） pathway, 8-oxoguanine glycosylase 1 （OGG1）. The latter successfully creates an abasic site, but the spermatozoa cannot process the oxidative lesion further because they lack the downstream proteins （APE1, XRCC1） needed to complete the repair process. It is the responsibility of the oocyte to continue the BER pathway prior to initiation of S-phase of the first mitotic division. If a mistake is made by the oocyte at this stage of development, a mutation will be created that will be represented in every cell in the body. Such mechanisms may explain the increase in childhood cancers and other diseases observed in the offspring of males who have suffered oxidative stress in their germ line as a consequence of age, environmental or lifestyle factors. The high prevalence of oxidative DNA damage in the spermatozoa of male infertility patients may have implications for the health of children conceived in vitro and serves as a driver for current research into the origins of free radical generation in the germ line.

关键词： DNA damage oxidative stress oxoguanine glycosylase 1 oocyte spermatozoa

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Introduction to Computing and Programming in Python, a Multimedia Approach Pap/Cdr

Introduction to Computing and Programming in Python, a Multi...

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2005年

作者： mark j. Guzdial

来源：畅想之星图书光盘版（南... 评论

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Abnormal colonic cholinergic and nitrergic activities in relation to elastosis in uncomplicated diverticular disease

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World j.urnal of Gastroenterology 2010年第36期16卷 4625-4626页

作者： mark Golder Center for Academic Surgery Institute of Cell and Molecular ScienceBarts and the London School of Medicine and DentistryQueen Mary UniversityLondon E11BBUnited Kingdom

I read with interest the review on the pathogenesis of diverticular disease by Commane et al in World j.Gastroenterol 2009;15(20):***,I would like to discuss several important errors that the authors made whilst citin... 详细信息

关键词： Diverticular disease Neural Acetylcholine Nitric oxide Elastin Protein gene product

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Do introduced honeybees affect seed set and seed quality in a plant adapted for bird pollination?

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j.urnal of Plant Ecology 2017年第4期10卷 721-729页

作者： Amy-Marie Gilpin j.stin C.Collette Andrew j.Denham mark K.j.Ooi David j.Ayre Centre for Sustainable Ecosystem Solutions School of Biological SciencesUniversity of WollongongNorthfields AvenueWollongongNSW 2522Australia NSW Department of Premier and Cabinet Office of Environment and HeritagePO Box 1967HurstvilleNSW 2220Australia Centre for Ecosystem Science School of BiologicalEarth and Environmental SciencesUniversity of New South WalesSydneyNSW 2052Australia

Aims Worldwide,evidence suggests that exotic pollinators can disrupt plant mating ***,few studies have determined if pol-lination by the honeybee Apis mellifera(the world’s most widely introduced pollinator)reduces offspring quality when compared with pollination by native *** Australian Proteaceae provides an excellent opportunity to test the impact of honeybees in pol-lination systems that are adapted to birds and non-flying *** We compared the frequency of flower visitation and foraging behav-iour of birds and insects within seven populations of Banksia *** ericifolia is hermaphroditic and has large nectar-rich,orange inflorescences typical of bird and mammal pollinated *** a subset of the study populations,we compared the qual-ity of seed produced via an exclusion treatment(that only allowed invertebrates to access flowers)with an open-pollination treatment(potentially visited by mammals,birds and invertebrates),by meas-uring seed weight,germination rates(T50),percent germination,seedling height after 14 days since the emergence of the cotyledon and time to emergence of the *** Findings Apis mellifera was the only apparent insect pollinator and the most frequent flower visitor,while the open treatment inflorescences were also frequently visited by avian pollinators,primarily hone-yeater *** foraging behaviour of honeybees and honeyeat-ers showed striking differences that potentially affect patterns of pollen *** made significantly greater proportions of within *** plant movements and only 30%(n=48)of honeybees foraged for pollen(nectar foragers carried no pollen)whilst all birds were observed to contact both stigmas and anthers when foraging for *** these fundamental differences in behaviour,there was little effect of treatment on seed set or *** data show that while honeybees appear to alter patterns of pollen transfer within *** popu

关键词： Apis mellifera Banksia ericifolia Proteaceae seedling performance seed vigour

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A note on the estimation of variance for big BAF sampling

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Forest Ecosystems 2020年第4期7卷 819-832页

作者： j.ffrey H.Gove Timothy G.Gregoire mark j.Ducey Thomas B.Lynch USDA Forest Service Northern Research Station271 Mast RoadDurham NH03824USA. School of Forestry&Environmental Studies Yale University360 Prospect StNew Haven CT06511USA. Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham NH03824USA. Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater OK74078USA.

Background:The double sampling method known as“big BAF sampling”has been advocated as a way to reduce sampling effort while still maintaining a reasonably precise estimate of volume.A well-known method for variance determination,Bruce’s method,is customarily used because the volume estimator takes the form of a product of random ***,the genesis of Bruce’s method is not known to most foresters who use the method in ***:We establish that the Taylor series approximation known as the Delta method provides a plausible explanation for the origins of Bruce’s *** were conducted on two different tree populations to ascertain the similarities of the Delta method to the exact variance of a ***,two alternative estimators for the variance of individual tree volume-basal area ratios,which are part of the estimation process,were compared within the overall variance estimation ***:The simulation results demonstrate that Bruce’s method provides a robust method for estimating the variance of inventories conducted with the big BAF *** simulations also demonstrate that the variance of the mean volume-basal area ratios can be computed using either the usual sample variance of the mean or the ratio variance estimators with equal accuracy,which had not been shown previously for Big BAF ***:A plausible explanation for the origins of Bruce’s method has been set forth both historically and mathematically in the Delta *** most settings,there is evidently no practical difference between applying the exact variance of a product or the Delta method—either can be used.A caution is articulated concerning the aggregation of tree-wise attributes into point-wise summaries in order to test the correlation between the two as a possible indicator of the need for further covariance augmentation.

关键词： Bitterlich sampling Delta method Double sampling Forest inventory Horizontal point sampling Variance of a product

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An approximate point-based alternative for the estimation of variance under big BAF sampling

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Forest Ecosystems 2021年第3期8卷 439-457页

作者： Thomas B.Lynch j.ffrey H.Gove Timothy G.Gregoire mark j.Ducey Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA USDA Forest Service Northern Research Station271 Mast RoadDurham 03824NHUSA Yale School of Environment Yale University360 Prospect StNew Haven 06511CTUSA Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham 03824NHUSA

Background:A new variance estimator is derived and tested for big BAF(Basal Area Factor)sampling which is a forest inventory system that utilizes Bitterlich sampling(point sampling)with two BAF sizes,a small BAF for tree counts and a larger BAF on which tree measurements are made usually including DBHs and heights needed for volume ***:The new estimator is derived using the Delta method from an existing formulation of the big BAF estimator as consisting of three sample *** new formula is compared to existing big BAF estimators including a popular estimator based on Bruce’s ***:Several computer simulation studies were conducted comparing the new variance estimator to all known variance estimators for big BAF currently in the forest inventory *** simulations the new estimator performed well and comparably to existing variance ***:A possible advantage of the new estimator is that it does not require the assumption of negligible correlation between basal area counts on the small BAF factor and volume-basal area ratios based on the large BAF factor selection trees,an assumption required by all previous big BAF variance estimation *** this correlation was negligible on the simulation stands used in this study,it is conceivable that the correlation could be significant in some forest types,such as those in which the DBH-height relationship can be affected substantially by density perhaps through *** derived a formula that can be used to estimate the covariance between estimates of mean basal area and the ratio of estimates of mean volume and mean basal *** also mathematically derived expressions for bias in the big BAF estimator that can be used to show the bias approaches zero in large samples on the order of 1n where n is the number of sample points.

关键词： Bitterlich sampling Delta method Double sampling Estimator bias Forest inventory Horizontal point sampling Variance of a product Volume basal area ratio Covariance estimation

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Validity of a noninvasive estimation of deep body temperature when wearing personal protective equipment during exercise and recovery

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Military Medical Research 2019年第4期6卷 328-339页

作者： Andrew P.Hunt mark j.Buller Matthew j.Maley j.seph T.Costello Ian B.Stewart School of Exercise and Nutrition Sciences&Institute of Health and Biomedical Innovation Queensland University of TechnologyBrisbaneQLDAustralia United States Army Research Institute of Environmental Medicine NatickMAUSA Extreme Environments Laboratory Department of Sport and Exercise ScienceUniversity of PortsmouthPortsmouthUK

Background:Deep body temperature is a critical indicator of heat ***,direct measures are often invasive,costly,and difficult to implement in the *** study assessed the agreement between deep body temperature estimated from heart rate and that measured directly during repeated work bouts while wearing explosive ordnance disposal(EOD)protective clothing and during ***:Eight males completed three work and recovery periods across two separate *** consisted of treadmill walking on a 1%incline at 2.5,4.0,or 5.5 km/h,in a random order,wearing EOD protective *** temperature and relative humidity were maintained at 24℃and 50%[Wet bulb globe temperature(WBGT)(20.9±1.2)℃]or 32℃and 60%[WBGT(29.0±0.2)℃]on the separate days,*** rate and gastrointestinal temperature(TGI)were monitored continuously,and deep body temperature was also estimated from heart rate(ECTemp).Results:The overall systematic bias between TGI and ECTemp was 0.01℃with 95%limits of agreement(Lo A)of±0.64℃and a root mean square error of 0.32℃.The average error statistics among participants showed no significant differences in error between the exercise and recovery periods or the environmental *** TGI levels of(37.0–37.5)℃,(37.5–38.0)℃,(38.0–38.5)℃,and>38.5℃,the systematic bias and±95%Lo A were(0.08±0.58)℃,(–0.02±0.69)℃,(–0.07±0.63)℃,and(–0.32±0.56)℃,***:The findings demonstrate acceptable validity of the ECTemp up to 38.5℃.Conducting work within an ECTemp limit of 38.4℃,in conditions similar to the present study,would protect the maj.rity of personnel from an excessive elevation in deep body temperature(>39.0℃).

关键词： Protective clothing Body core temperature Heat strain Heat stress Kalman filter Explosive ordnance disposal

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Increased Incidence of Scarlet Fever--China,1999−2018

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China CDC weekly 2019年第5期1卷 63-66页

作者： Yuanhai You Ying Qin mark j.Walker Luzhao Feng j.anzhong Zhang State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseaseNational Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Division of Infectious Diseases Chinese Center for Disease Control and PreventionBeijingChina School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre The University of QueenslandBrisbaneQLDAustralia.

What is already known about this topic?Scarlet fever had high incidence between the 1950s and 1980s,but during the 1980s and 1990s,the incidence of scarlet fever dropped to a relatively low and stable levels in *** is added by this report?Starting in 2011,scarlet fever incidence significantly increased in *** the eight years between 2011 and 2018,479,555 cases were reported,which exceeded the total number of 241,365 cases reported in the previous twelve years 1999–*** are the implications for public health practice?Both patient and pathogen epidemiological surveillance need to be heightened to monitor serious cases of scarlet fever and to implement timely control measures.

关键词： fever Fever Incidence

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Therapy decisions for the symptomatic patient wil metastatic castration-resistant prostate cancer

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Asian j.urnal of Andrology 2015年第6期17卷 936-938,I0008页

作者： mark C markowski Kenneth j.Pienta j.hns Hopkins University School of Medicine Baltimore MD 21287 USA.

Metastatic prostate cancer continues to kill approximately 30,000 men per year. Since 2010, five new therapeutic agents have been Food and Drug Administration （FDA） approved to treat metastatic castration-resistant prostate cancer （mCRPC）. With the increasingnumber of therapies available to clinicians, the most effective sequence in which to implement these treatments remains unknown. The presence or absence of symptoms （i.e., bony pain, visceral crisis） is a key parameter that informs the decision-making process regarding therapy. Treatment algorithms based on： 1） asymptomatic/minimal symptoms, 2） moderate symptoms or chemotherapy ineligible or 3） symptomatic disease need to be developed.

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A novel access method for endovascular procedures in the porcine model

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中国介入影像与治疗学 2004年第2期1卷 147-150页

作者： Yong-hua DONG mark j.Sands DepartmentofRadiology DeskL-10， DepartmentofRadiology DeskHB6TheClevelandClinicFoundation9500EuclidAvenueClevelandOH44195

Obj.ctive To evaluate the use of the saphenous artery as an alternative access for endovascular procedures in the porcine model. Methods Fourteen adult pigs (25-35 kg) were used in this study, 3 pigs from an acute study and 11 from chronic studies. A 2-3 cm incision was made and a saphenous artery cutdown was performed in 24 sides. Micropuncture sets (Boston Scientific) or 18 G puncture needles were used to access the artery. Different sizes of introducers (4-7 F) were used to establish endovascular access. Angiographic catheters were then used to confirm if the access was usable. Four saphenous arteries were explanted in the pigs from a chronic study 4 to 28 days after surgical procedure. Results The saphenous artery was very easy to expose and 4-5 F introducer sheaths were able to be inserted to establish access for endovascular procedures in the pigs. The saphenous artery was unable to accomodate an introducer with a size larger than 6 F. Four saphenous arteries were inj.red when 5 and 6 F introducers were used, but angiographic procedures could still be performed. Morphologic evaluation of the explanted arteries demonstrated occlusion of the saphenous arteries without inj.ry or disruption of the adj.cent femoral arteries. Conclusion The saphenous artery can be used as an access site in pigs for angiographic and interventional procedures if the catheter size is less than 6 F. This vessel is easier to access and can preserve the femoral artery for repeat procedures in the future.

关键词：异常通路方法猪模型静脉通路《中国介入影像与治疗学》

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