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简介：ThedosimetricphosphorsLi_3PO_4:M(M=Tb,Cu)wereproducedbymodifiedsolid-statemethod.ThestructuralandmorphologicalcharacterizationwascarriedoutthroughX-raydiffraction(XRD)andscanningelectronmicroscope(SEM).Additionally,thephotoluminescence(PL),thermoluminescence(TL)andopticallystimulatedluminescence(OSL)propertiesofpowderLi_3PO_4dopedwithTbandCuwerestudied.ItisadvocatedthatLi_3PO_4:CuphosphornotonlyshowshigherOSLsensitivity(25timesormore)butalsogivesfasterdecayinOSLsignalsthanthatofLi_3PO_4:Tb~(3+)phosphor.Theminimumdetectabledose(MDD)ofLi_3PO_4:M(M=Tb,Cu)phosphorsisfoundtobe21.69×10~(-3)and3.33×10~(-6)J·kg~(-1),respectively.InOSLmode,phosphorshowslineardoseresponseintherangeof0.02-20.00J·kg~(-1).InTLmode,sensitivityofLi_3PO_4:CuphosphorismorethanthatofLi_3PO_4:Tbphosphor.Thekineticsparameterssuchasactivationenergyandfrequencyfactorsweredeterminedbypeakshapemethod,andphotoionizationcrosssectionsofpreparedphosphorwerecalculated.

简介：摘要本文为淘锡坑钨矿（+356m～+56m水平）开采设计方案通过章源钨业淘锡坑钨矿地质状况调研以及开采要求的综合分析比较，确定了开拓方案采用平硐联合盲竖井开拓；采矿方法为浅孔留矿法；采用中央对角式通风系统；井下运输为电机车有轨运输。本文初步形成了完整的地下开采方案。

简介：介绍N8891、3M4650精研机流球道改造。将原来钢板、钢筋焊接式结构改为胶木钢板组合式，避免钢球表面因与金属接触摩擦产生划伤，同时提高流球道定位精度，避免钢球与研磨盘沟槽棱边碰撞造成缺陷。

简介：利用拟生灭过程和矩阵几何解的方法研究了只允许部分服务台异步单重休假的M/M/c排队系统,给出了系统的稳态指标的计算方法和条件随机分解结果,最后指出一些较简单的排队模型是本文的特例.

简介：拍照、录音、FM、MP3．JAVA……手机不仅仅是一种通话工具．而且越来越多地成为一种娱乐工具。作为国产手机的领军人物，波导也于近期一口气推出了5款MP3手机，率先登场的是M09、M10N款音乐手机。

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简介：意法半导体（ST）新一代串行闪存芯片M25P10．A、M25P20和M25P40，专门为可靠性要求极高的汽车应用而设计。

简介：Amajorprobleminhybridriceproductionistheoccurrenceofleafsenescenceduringthegrainfillingstagethatcanresultinreductionofyield.Changesincontentsofseveralendogenoushormonesarerelatedtoleafsenescence.TherelationshipbetweenendogenoushormonesandleafsenescenceinthericehybridTiyou418anditsparentsTijinandC418,wasundertakenforinvestigation.Indicatorsofleafsenescence,includingsuperoxidedismutase(SOD)activity,malondialdehyde(MDA)accumulationandchlorophyllcontent,aswellasthecontentsofabscisicacid(ABA),zeatinriboside(ZR),gibberellin(GA1/3)andauxin(IAA)intheleavesweredetermined.Differentratesofleafsenescencewereobservedinthethreematerials.SenescenceoccurredearliestandfastestinTijin,followedbyTiyou418andthenC418.AsimilartrendwasrecordedinABA,ZR,andIAAcontentsduringthegrainfillingstageinthethreematerials.Changesin(GA1/3+ZR+IAA)/ABAratioswerealsosimilar,beingquitestableduringtheearlystageofleafsenescence,anddecreasingmarkedlyduringthelatestage.TheratiodeclinedmoredramaticallyinTijin,inaccordancewithitsfasterleafsenescence.Theresultssuggestthattheratioof(GA1/3+ZR+IAA)/ABAregulateschlorophyllcontent,SODactivity,MDAcontentandmembranelipidperoxidation.Itispostulatedthatendogenoushormonesmayplayaroleintheregulationofleafsenescenceinasystematicway.

简介：AbstractBackground:Changes in thyroid hormone levels are commonly recognized characters among the elderly, which were reported to potentially influence incident frailty. Therefore, we examined the cross-sectional associations of thyroid hormones (THs) with frailty as well as the five components characterizing frailty (fatigue, resistance, ambulation, number of illnesses, and loss of weight) among the oldest-old.Methods:Four hundred and eighty-seven community-dwelling oldest-old from a local community in Haidian District, Beijing, participated in our recruitment campaign between April 2019 and May 2020. The primary outcomes were a definitive diagnosis of frailty according to the FRAIL scale (Fatigue, Resistance, Ambulation, Illnesses, Loss of weight) and a positive score for each frailty subdomain. Demographic information (age, sex, marital status, and educational status), comorbidities, and details on the participants’ lifestyles were recorded. Serum THs including free triiodothyronin (fT3), triiodothyronine (T3), free thyroxine (fT4), and thyroxine (T4) and thyroid stimulating hormone (TSH) levels were also measured at the beginning of our study. Logistic regressions were conducted to screen for potential risk factors for frailty and its subdomains.Results:Among the total 487 subjects at enrollment, 60 (12.23%) of them were diagnosed with subclinical hypothyroidism and 110 (22.59%) of the total population scored positive for frailty. Logistic regression analyses adjusted for all potential confounders, showed that frailty was significantly associated with the serum TSH concentration (odds ratio [OR]: 1.06), fT3 concentration (OR: 0.54), and subclinical hypothyroidism score (OR: 2.18). The association between fT4 and frailty was absent in our observational study. The fT3/fT4 ratio characterizing peripheral hormone conversion was also tested to be correlated with frailty.Conclusion:Subclinical hypothyroidism, higher TSH level, lower fT3 level, and decreased fT3/fT4 ratio were all associated with frailty assessed by the FRAIL scale among the community-dwelling oldest-old, suggesting a relevant role of thyroid function in aging. Future longitudinal studies are warranted to determine the casual relationship between thyroid dysfunction and frailty in the oldest-old.

简介：AbstractBackground:The association between sex hormone-binding globulin (SHBG) and renal function has rarely been reported in men. We aimed to investigate the above association in a community-based Chinese population.Methods:A total of 5027 men were included from the survey on prevalence for metabolic diseases and risk factors, which is a population-based study conducted from 2014 to 2016 in Eastern China. The estimated glomerular filtration rate (eGFR) was calculated according to the chronic kidney disease Epidemiology Collaboration equation. Low eGFR was defined as eGFR <60 mL·min-1·1.73 m-2.Results:After adjusting for age, smoking, metabolic factors, and testosterone, through increasing quartiles of SHBG, a significantly positive association between SHBG quartiles and eGFR was detected in men (Q1 vs. Q4, β -2.53, 95% confidence interval -3.89,-1.17, Ptrend < 0.001). Compared with the highest quartile of SHBG, SHBG in the lowest quartile was associated with 96% higher odds of low eGFR (odds ratio 1.96, 95% confidence interval 1.10, 3.48) in the model after full adjustment. According to the stratified analyses, the associations between a 1-standard deviation increase in serum SHBG and the prevalence of low eGFR were significant in men aged ≥60 years old, waist circumference <90 cm, diabetes (no), hypertension (yes), dyslipidemia (no), and nonalcoholic fatty liver disease (no).Conclusions:Lower serum SHBG levels were significantly associated with lower eGFR and a higher prevalence of low eGFR in Chinese men independent of demographics, lifestyle, metabolic-related risk factors, and testosterone. Large prospective cohort and basic mechanistic studies are warranted in the future.

简介：BACKGROUND:Changesinthecardiacautonomicnerveareconsideredtobeimportantfactorsinthemechanismsofheartfailure.Itispossibletoreduceorslowdownnervedegenerationandnecrosis,providedthatpatientstakeeffectiveneuroprotectantsduringtheearlystagesofheartfailure.Moreover,itispossibletorelievethepathologicalprocessandreducetheriskofdeath.OBJECTIVE:Tostudytheeffectofgrowthhormonereleasingpeptide(GHRP)oncardiaccholinergicnervefiberdensitydistributioninaratmodelofheartfailure,andverifywhetherGHRPcanamelioratedenervation.DESIGN,TIMEANDSETTING:ArandomizedcontrolledstudywasperformedattheKeyLaboratoryofAnatomy,HarbinMedicalUniversity,betweenJuneandOctober2009.MATERIALS:Fiftyadult,healthy,female,Wistarrats,weighing(200±20)g,wererandomlydividedintoGHRP(n=30),model(n=10),andshamoperation(n=10)groups.GHRP-2wasmadeinShanghai,China(batchNo.z071212-03).METHODS:AcutemyocardialinfarctionwasestablishedbyligatingtheleftanteriordescendingcoronaryarteryintheGHRPandmodelgroups.Fiveweekslater,myocardialfunctionwasdetectedusingcolorultrasoundelectrocardiograph.Ejectionfraction<60%wasconsideredtobeasuccessfulmarkerofchronicheartfailuremodels.However,theleftanteriordescendingcoronaryarterywasnotligatedintheshamoperationgroup.TheGHRPgroupwasinjectedwith100μg/kgGHRP-2,andtheothertwogroupswereinjectedwiththesamevolumeofphysiologicalsaline,onceperday.MAINOUTCOMEMEASURES:After4weeks,pathologicalchangesincardiaccholinergicnervefibersweredetectedunderopticmicroscopyfollowinghematoxylin/eosinstaining.Inaddition,densitydistributionwasmeasuredusingamulti-functioncolorpathologicalimagesystem.RESULTS:Intheshamoperationgroup,myocardialcellswereregular,uniformlystained,andnoinflammatorycellswerepresent.Inthemodelgroup,myocardialcellswereunevenlystained,exhibitednuclearatrophy,degeneration,dissolution,ordisap

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简介：Theactivesiteof3CLproteinase(3CL^por)forcoronaviruswasidentifiedbycomparingthecrystalstructuresofhumanandporcinecoronavirus.Theinhibitorofthemainproteinofrhinovirus(Ag7088)couldbindwith3CL^proofhumancoronavirus,thenitwasselectedasthereferenceformoleculardockinganddatabasescreening.Theligandsfromtwodatabaseswereusedtosearchpotentialleadstructureswithmoleculardocking.SeveralstructuresfromnaturalproductsandACD-SCdatabaseswerefoundtohavelowerbindingfreeenergywith3CL^prothanthatofAg7088.ThesestructureshavesimilarhydrophobicitytoAg7088.Theyhavecomplementaryelectrostaticpotentialandhydrogenbondaeceptoranddonorwith3CL^pro,showingthatthestrategyofanti-SARSdrugdesignbasedonmoleculardockinganddatabasescreeningisfeasible.

简介：神经生长因子（nervegrowthfactor．NGF）属神经营养因子家族，广泛分布于中枢及外周神经系统，不仅在神经系统的发育存活中起重要作用，而且参与外周伤害性疼痛感受的产生与调节。近年来由于对NGF在急、慢性疼痛及痛觉过敏中作用的认识不断增强．一种新的抑痛方法一一抗-NGF（anti-NGF）治疗悄然兴起。它是通过NGF的抗血清IgG封闭NGF,抑制其与受体结合及受体的自磷酸化作用，从而部分阻断或减弱疼痛的进程。由于该方法抑痛效果明显，且不与神经营养因子家族的其他成员作用，尚未发现明显不良反应及成瘾性，对中枢神经系统也无直接作用，因此极有可能成为疼痛治疗的新热点。