Should ocular Demodex be checked and treated in refractory keratitis patients without blepharitis?

AIM:To evaluate the correlation between Demodex infestation and keratitis,and to assess demodicosis using a simple approach.METHODS:A modified slit lamp illumination(at 40×magnification)was used to observe Demodex tails in 40patients with refractory keratitis and 80 healthy controls.Bacterial smear and culture of the conjunctival sac and corneal lesion were performed to identify the pathogen.Tea tree oil ointment(TTOO)was added as a Demodex killing agent for lid scrubs to the treatment when Demodex infestation was confirmed.RESULTS:Demodex tails were found in all patients compared to 42/80 of the controls(P<0.01).Seventeen patients presented blepharitis,while 23 were free of scales and inflammation at the lid margin.The demodicosis was mild,moderate,and severe in 8,19,and 13 patients,respectively,compared to mild in 42 controls(P<0.01).The keratitis was mild,moderate,and severe in 13,19,and 8patients,respectively.The severity of Demodex infestation was not correlated to the severity of keratitis(P=0.126).The growth of Staphylococcus was revealed in nine patients who did not react to antibiotic eye drops prior to the TTOO treatment.Patients’signs and symptoms got resolved after the lid scrub with TTOO.CONCLUSION:Ocular Demodex needs to be checked and treated in refractory keratitis patients with or without blepharitis.A slit-lamp illumination under high magnification favors the judgment of the severity of Demodex infestation.

Intense Pulsed Light Therapy for Patients with Meibomian Gland Dysfunction and Ocular Demodex Infestation

To observe the clinical changes of meibomian gland dysfunctipn(MGD)and ocular Demodex infestation after intense pulsed light(IPL)treatment to further examine the mechanism of IPL treating patients with MGD and ocular Demodex infestation.The medical records of 25 patients(49 eyes)with MGD treated with IPL,were retrospectively examined to determine outcomes.Associated ocular-surface parameters(ocular surface disease index,OSD1;lipid layer thickness,LLT;noninvasive first breakup time,NIF-BUT;noninvasive average breakup time,NIAvg?BUT;tear film breakup area,TBUA;Schirmer I Test,SIT;corneal fluorescein staining,CFS),eyelid margin abnormalities,meibum quality and expressibility,MG morphological parameters(macrostructure and microstructure),and the number of Demodex infestation were examined before and after treatment.The MG microstructure and the Demodex infestation were examined via in vivo confocal microscopy(IVCM).The results showed that there were statistically significant differences in associated ocular-surface parameters(all P<0.05)before and after IPL treatment,except SIT(P=0.065).Eyelid margin abnormalities,meibum quality and expressibility obviously improved in upper and lower eyelid after IPL treatment(all P<0.0001).MG macrostructure(MG dropouts)decreased in upper(P=0.002)and lower eyelid(P=0.001)after IPL treatment.The nine parameters of MG microstructure in upper and lower eyelid all distinctly improved after IPL treatment(all P<0.0001).The mean number of Demodex mites on the upper lid margin(6.59±7.16 to 3.12±3.81/9 eyelashes)and lower lid margin(2.55±2.11 to 1.29±1.53/9 eyelashes)significantly reduced after IPL treatment(all P<0.0001).The Demodex eradication rate was 20%(8/40)in upper lid margin and 34.15%(14/41)in lower lid margin.These findings indicate that IPL shows great therapeutic potential for patients of MGD and ocular Demodex infestation.

The association between demodex infestation and ocular surface manifestations in meibomian gland dysfunction

AIM： To investigate the association between ocular demodex folliculorum infestation and ocular surface manifestations in meibomian gland dysfunction（MGD）.METHODS： Eight-six patients with MGD were enrolled. All enrolled subjects were tested in the following sequence： ocular surface disease index（OSDI）, slit-lamp biomicroscope examination, corneal surface regularity index（SRI） and surface asymmetry index（SAI）, tear fluid collection, fluorescein tear film break-up time（F-BUT）, corneal fluorescein staining（CFS）, Schirmer I test（SIT） and demodex folliculorum counting. Tear matrix metalloproteinase（MMP）-9 activity was assessed using MMP-9 activity assay kit.RESULTS： Among 86 MGD patients, 40 were positive for demodex. The ocular demodex-positive group showed significantly increased scores of OSDI（25.96±13.74 vs 18.07±11.55, P=0.01）, lid margin abnormality（2.38±0.87 vs 1.98±0.91, P=0.04） and CFS（1.28±2.00 vs 0.94±1.36, P=0.01） compared to the ocular demodex-free group. The tear MMP-9 activity was higher in the ocular demodex-positive group（102.9±32.4 ng/mL） than the ocular demodex-free group（46.2±19.2 ng/mL, P=0.03）. There was no significant difference in meibum quality and expressibility, SRI, SAI, F-BUT and SIT between the two groups（P〉0.05 for each）. No significant correlation was noted between the number of demodex and ocular surface parameters in demodexpositive MGD group（P〉0.05 for each）.CONCLUSION： Ocular demodex folliculorum infestation may be associated with ocular discomfort and ocular surface damage in MGD.

Correlation Demodex Folliculorum and Skin Biophysical Parameters

Purpose: Demodex folliculorum is a transparent mite, 0.3 - 0.4 mm long, which asymptomatically parasitizes the human pilosebaceous follicles. D. folliculorum is observed in normal skin with a prevalence of 100% and a density of ≤ 5 D/cm2 in the adult population. Materials and Methods: This study evaluated the differences in pH on the five facial sites between the two populations with and without D. folliculorum. The relationship between pH and skin surface oil was analyzed in populations with and without Demodex mites. Mongolian 750 subjects (370 males and 380 females) aged 16 - 84 years, who lived in Ulaanbaatar city, were enrolled in this study. The eligibility criteria included a minimum age of 16 and no physical and dermatologic illness, no cosmetic. Results: Skin surface oil among the five facial areas differed significantly in both subjects with and without Demodex folliculorum (P < 0.001). When the skin surface oil on the T-zone, U-zone was compared, those on the T-zone were significantly higher than those of the U-zone (P < 0.001) in both populations (P< 0.01). The pH levels on the five facial sites, and U-zone, T-zone and MFpH differed significantly in among both subjects with and without Demodex folliculorum (P < 0.001). In both groups, the pH levels of the U-zone were significantly lower than the pH of the T-zone (P Conclusions: Among the five facial sites in subjects with Demodex folliculorum, there were significant negative correlations between skin surface oil and pH on the forehead (p < 0.001, r = 652), cheek (P < 0.001, r = 0.656), nose (P < 0.001, r = 0.754), chin (P < 0.001, r = 0.679), and T-zone (P < 0.001, r = 0.698), MFSE-MFpH (P < 0.001, r = 0.483). In contrast, among the five sites in subjects without Demodex folliculorum, a significant negative correlation between skin surface oil and pH was observed on the forehead (p < 0.001, r = 766), cheek (P < 0.001, r = 0.798), nose (P < 0.001, r = 0.706), chin (P < 0.001, r = 0.823), and T-zone (P < 0.001, r = 0.602), U-zone (P < 0.001, r = -0.550)

Clinical effect of Chinese medicine aerosol fumigation on demodex infection related meibomian gland dysfunction

Objective:To explore the clinical effect of Chinese medicine aerosol fumigation on demodex infection related meibomian gland dysfunction.Methods:In this prospective study,60 patients(120 eyes)were selected and randomly divided into 2 groups:the treatment group(30 cases,60 eyes)was treated with Chinese medicine aerosol fumigation and meibomian gland massage,the control group(30 cases,60 eyes)was treated with meibomian gland massage.Observation of Demodex count,symptom scores,break-up time(BUT),Schirmer I test(SIT),meibomian gland secretion function scores and eyelid fat traits scores were used to compare the difference between before and after treatment.Results:There was no significant difference in Demodex count,symptom scores,BUT,SIT,meibomian gland secretion function scores and eyelid fat traits scores between the 2 groups before treatment(P>0.05).After treatment,symptom scores,meibomian gland secretion function scores and eyelid fat traits and Demodex count of the treatment group were significantly reduced(P<0.01).Conclusion:Chinese medicine aerosol fumigation can relieve symptoms of of demodex infection related meibomian gland dysfunctionand reduce the number of ocular Demodex.

饵剂投放站对田间红火蚁的饵剂搬运量及防控效果研究

饵剂诱杀是防控红火蚁Solenopsis invicta Buren最广泛和最有效的措施。本研究利用一种新型饵剂投放站(简称饵剂站)对比分析红火蚁工蚁对0.08%茚虫威杀蚁饵剂及其载体的搬运量,并使用5 g/巢、10 g/巢、20 g/巢3种剂量的饵剂对田间红火蚁蚁巢进行单蚁巢处理,评价饵剂站对田间红火蚁的饵剂搬运量及防控效果的影响。结果表明,红火蚁工蚁对饵剂站内0.08%茚虫威饵剂及其载体的搬运量少于直接撒施处理方式的搬运量。施药24 h后,红火蚁工蚁对饵剂站内和直接撒施的0.08%茚虫威饵剂搬运量分别为14.84±3.18 g和17.71±5.88 g,差异不显著。使用饵剂站施用10 g、20 g饵剂处理28 d后,工蚁减退率、蚁巢减退率、蚁群级别降低率和综合防治效果均可达到90%以上,与直接撒施处理方式均无显著差异。虽然饵剂站会一定程度上降低红火蚁工蚁对饵剂的搬运量,但却不影响对红火蚁的防控效果,基于其防雨、防潮的优点,饵剂站可显著延长红火蚁防控的窗口期。

不同型号鼠夹和不同诱饵在农村地区捕鼠效果比较

目的通过比较不同型号鼠夹搭配不同诱饵的捕鼠效果,为今后工作中合理选择鼠夹和诱饵提供依据。方法使用中号钢板夹和大号钢板夹分别搭配生花生米和鲜肉交替布放在农村居民区和农田,比较捕获率及鼠种构成。结果大号鼠夹捕获率高于中号鼠夹(P<0001,OR=3280,95%CI:2414~4456),用鲜肉作为诱饵的捕获率低于生花生米(P=0020,OR=0723,95%CI:0550~0950),大号鼠夹和生花生米饵在捕获农田优势鼠种黑线姬鼠方面有优势,大号鼠夹更容易捕获到体型较大的褐家鼠。结论不同鼠夹型号和诱饵对于捕鼠效果影响较大,建议鼠害监测可用大号鼠夹和生花生米。

BG-Trap法与双层叠帐法对登革热媒介白纹伊蚊监测效果的比较

目的比较BG-trap法与双层叠帐法对登革热媒介白纹伊蚊的监测效果,进一步探讨BG-trap法用于登革热媒介伊蚊监测的可能性,为制定更有效的登革热防控策略提供参考依据。方法实验选取江苏省3个设区市的6个户外监测点,于8—9月的3天时间中,分别于每日16:00-16:30、17:00-17:30、18:00-18:30三个时段同步开展BG-Trap法和双层叠帐法监测。结果BG-Trap法和双层叠帐法均能够有效地捕获白纹伊蚊的雌蚊,双层叠账法捕获的白纹伊蚊占比高于BG-Trap法(χ^(2)=16.034,P<0.01),两种方法捕获的白纹伊蚊雌蚊构成比之间差异无统计学意义(χ^(2)=0.162,P=0.687)。BG-Trap法捕获的白纹伊蚊平均密度指数为7.85±5.23只/(台·h),低于双层叠帐法的27.04±13.86只/(顶·h),差异有统计学意义(t=6.73,P<0.001)。结论BG-Trap法对登革热媒介白纹伊蚊监测效果不及双层叠帐法,其能否应用于登革热媒介伊蚊监测有待于进一步研究。

乌东德水电站尾水集鱼平台集鱼效果影响因素分析

为研究乌东德水电站尾水集鱼平台集鱼效果与诱鱼措施、下游水文要素等影响因素之间的关系,通过分析2021年4~10月乌东德水电站右岸尾水集鱼平台运行数据以及同期水文数据,采用数据对比分析法初步提出了水文指标变化与集鱼效果之间的趋势关系。数据分析显示:金沙江中游江段投放肉食型饵料诱鱼增益效果更好;6~7月开启灯光诱鱼,可显著提升光照敏感鱼类的收集率;短时间的下泄流量增加对刺激鱼类洄游,增加集鱼数量没有明显作用,而超过5 d以上连续的下泄流量增加可以刺激鱼类洄游,提升集鱼数量。研究成果可为优化金沙江中游水电站生态调度以及提升集鱼系统集鱼效率提供支撑。

水丝蚓及人工饲料对草金鱼生长和体色的影响

为评价水丝蚓或人工饲料对草金鱼生长和体色的影响,选择初始体质量(7.82±1.84)g、体长(5.73±0.45)cm的草金鱼,分别投喂水丝蚓(SY组)和人工饲料(SL组),定期测定体质量和体色色度。结果显示,SY组试验鱼增质量率、特定生长率显著高于SL组(P<0.05),肥满度差异不显著(P>0.05);两组试验鱼体质量直线斜率差异不显著(P>0.05)。两组草金鱼体色L*(亮度)值与投喂时间呈正相关趋势,a*(+a*红,-a*绿)、b*(+b*黄,-b*蓝)值均呈负相关趋势;两组试验鱼色度值直线斜率(K)差异不显著(P>0.05);试验结束时,SY组试验鱼体表a*和b*值均显著高于SL组(P<0.05)。研究表明,草金鱼体质量与生长时间的线性相关性较强,投喂水丝蚓更容易被草金鱼接受,更能稳定促进其生长,但无论投喂水丝蚓或是人工饲料,其体表红色均会逐渐变淡。

环状RNA编码蛋白质在胃肠肿瘤中的研究进展

环状RNA(CircRNA)是一类具有连续、共价闭合、环状结构的单链RNA,生成机制与线性RNA存在较大差异。目前研究已发现部分CircRNA可以通过内部核糖体进入位点、N6-甲基腺苷和滚环翻译等非帽依赖性蛋白翻译机制来编码蛋白质,且编码的蛋白质可进一步通过蛋白诱饵或其他作用机制来调控同源线性蛋白质或下游信号通路,进而发挥生物学功能。已有研究表明CircRNA在各种疾病发生发展中发挥重要作用,特别是参与肿瘤生长增殖、侵袭转移和免疫调节等发生发展过程中。因此,通过阐明编码CircRNA产生的蛋白质在肿瘤发生发展中的表达情况和作用机制,有望为肿瘤诊治提供新的肿瘤标志物和潜在靶点。

活饵与饲料投喂对幼鳜肠肽酶活力及小肽转运、吸收的影响

以初始体重(6.77±0.64)g的鳜(Siniperca chuatsi)为实验对象,从消化道肠肽酶活力和小肽转运吸收方面比较研究鳜对活饵与饲料消化吸收能力的差异。实验采用3种分组投食策略,将鳜分活饵组(仅投喂活饵鱼)、饲料组(仅投喂饲料)、复投活饵组(以下简称复投组,先投喂饲料后活饵鱼)。活饵组、饲料组分别饲养22d,复投组经5d驯饲、15d饲料和2d活饵喂养。饲养结束时在各组进食0.5h、1h、2h、3h、6h、12h、16h时分别取样肠和幽门盲囊,测定氨肽酶和羧肽酶含量与活力,小肽转运载体基因Pept1a、Pept1b和Pept2 mRNA表达水平,及进食12h后肠内容物及粪便中残余小肽含量。结果表明:各组羧肽酶、氨肽酶含量变化无显著性规律,酶活力总体呈先升后降趋势;活饵组肽酶活力峰值显著高于复投组高于饲料组(P<0.01),复投组由饲料转喂活饵后,肠道肠肽酶活力显著上升;各组前肠、中肠及幽门盲囊Pept1a、Pept1b mRNA表达显著高于后肠(P<0.01),后肠则以Pept2 mRNA高表达(P<0.01)。在复投组摄食活饵后,小肽转运载体基因表达水平较饲料组迅速回升(P<0.01);摄食12h,复投组肠内容物小肽含量显著高于活饵组和饲料组,小肽吸收效率随消化时间延长而上升。饲料组粪便中小肽含量显著高于活饵组与复投组,未转运的小肽中含必需氨基酸居高。综上所述,投喂鳜配合饲料,对肠肽酶活力、小肽转运载体基因表达和小肽吸收速率均产生不利影响,鳜对饲料蛋白的分解和小肽转运吸收效率显著低于活饵鱼。

盐碱水池塘不同饵料投喂条件下拟穴青蟹生长、营养及血清生化指标的比较

为探究盐碱水池塘养殖条件下投喂不同饵料对池塘水质及拟穴青蟹生长、营养品质及血清生化指标的影响,实验设置青柳蛤、矛尾复虾虎鱼、鹰爪虾3种生物饵料组和1种人工配合饲料组,各组设置3个重复,实验周期4个月,分析各组池塘水质变化,并采用单因素方差分析(One-Way ANOVA)方法比较各组蟹的生长、营养及血清生化指标。结果显示,各组水温、盐度与pH差异较小,而溶解氧、氨氮、亚硝酸盐氮差异较大,其中,矛尾复虾虎鱼组溶解氧从11.5降至9.2 mg/L,而氨氮、亚硝酸盐氮分别从养殖初期0.44、0.022 mg/L上升到养殖末期的0.89、0.050 mg/L。青柳蛤组的体重(334 g)、增重率(332.7%)和特定生长率(0.076%/d)显著高于其他组,人工配合饲料组存活率最高,达到66.67%,矛尾复虾虎鱼组的肥满度(0.221 g/cm^(3))显著高于其他组;青柳蛤组的肌肉必需氨基酸中的缬氨酸、蛋氨酸、异亮氨酸、苯丙氨酸含量及肝胰腺呈味氨基酸总量和鲜味氨基酸总量在各组中最高,人工配合饲料组肝胰腺必需氨基酸中的苏氨酸、亮氨酸、赖氨酸、组氨酸含量在各组中最高,鹰爪虾组的肌肉呈味氨基酸总量和鲜味氨基酸总量在各组中最高,青柳蛤组的肌肉与肝胰腺饱和脂肪酸、多不饱和脂肪酸、脂肪酸含量均为最高;青柳蛤组的总蛋白含量显著高于其他组,矛尾复虾虎鱼组的总胆固醇显著高于其他组,人工配合饲料组的谷草转氨酶、甘油三酯、葡萄糖显著高于其他组,相关性分析显示青柳蛤等生物饵料常规营养与拟穴青蟹各生长指标存在显著正相关。研究表明,青柳蛤组拟穴青蟹在生长、营养及血清蛋白质指标上具有显著优势,可以作为盐碱水池塘养殖拟穴青蟹的适口饵料。本研究将为拟穴青蟹北方盐碱水池塘养殖和推广提供数据参考。

Factors affecting meibomian gland area loss in symptomatic adults

AIM:To characterize the distribution of meibomian gland(MG)area loss(MGL)and its relationship with demographic characteristics,mites,and symptoms.METHODS:This retrospective observational study included patients who visited the Dry Eye Clinic of Shenzhen Eye Hospital between June 2020 and August 2021.General patient characteristics,ocular symptoms,Demodex test results of the eyelid edges,and the results of a comprehensive ocular surface analysis were collected.MGL was analyzed using Image J software.RESULTS:This study enrolled 1204 outpatients aged 20-80(40.70±13.44)y,including 357 males(29.65%)and 847 females(70.35%).The patients were classified into mild(n=155;12.87%),moderate(n=795;66.03%),severe(n=206;17.11%),and extremely severe(n=48;3.99%)MGL groups.MGL was significantly larger in female than in male(P=0.006).The degree of MGL also significantly differed in age(P<0.001)and the more numbers of mites with severity(P<0.001).Multivariate disordered multinomial logistic regression analysis identified that female sex,older age,secretory symptoms,and a large number of mites were risk factors for MGL(P<0.05).CONCLUSION:Patients with MGL are more likely to be older,female,more numbers of mites,and increased secretion.

新疆干旱半干旱农田应用0.2%莪术醇饵剂防治害鼠的效果

为了解0.2%莪术醇饵剂在新疆干旱半干旱农田应用的可行性,2022年4月至7月,在新疆博州温泉县进行了该药防治害鼠试验。施药在3个试验点(即3个重复)进行,在害鼠繁殖高峰期前施药,投放药饵后30、60 d和90 d调查防控效果。结果显示:3个试验区域的结果趋势相似,校正灭效基本维持在50%以上。与空白对照区相比,优势鼠种灰仓鼠与根田鼠试验投饵区的雌鼠怀孕率明显下降,小家鼠、灰仓鼠平均胎仔数明显降低,小家鼠、灰仓鼠和根田鼠施药区域的鼠类个体的亚成体比例与对照区域明显下降,说明该药剂对当地害鼠的繁殖具有明显的控制作用,可达到控制害鼠数量的目的,适口性也较好,可以在当地推广应用。

Mosquito Control, Killing off the Females

In addition to causing discomfort, female mosquitoes introduce disease-carrying viruses and bacteria into the bloodstream of their victims. There are numerous publications describing the uses of sugary mosquito baits with promising results. Without temperature control measures however, these methods are mainly useful for only nectar-feeding insects, including male mosquitoes, because the warmth of the blood is a condition for the females to locate their meals. The efforts required to keep the baits fresh against the natural spoiling process make them less attractive or impractical to implement. These experiments address these issues by using warm baits of water, sugar, boric acid, and antibiotics. Overnight, the general areas became clear of blood-sucking female mosquitoes while in numbers, the harmless males concentrated into the immediate vicinities. Control vs. experiment protocol established no other logical explanation for this phenomenon other than that females were attracted and killed by the bait. As expected, there was no female mosquito’s activity in these areas. There weren’t many left to do the work.

Rare facial dermatological lesions associated with Demodex infection,besides acne vulgaris

I have read with great interest the recent article "A meta-analysis of association between acne vul- garis and Demodex infestation" by Zhao et al. (2012), published in Journal of

基于无人机低空投饵技术的高原鼠兔防控效果研究

为明确无人机在不同投饵参数下对高原鼠兔的防控效果,本研究采用不同剂量雷公藤甲素颗粒剂、C型肉毒梭菌毒素颗粒剂、C型肉毒梭菌毒素水剂和D型肉毒梭菌毒素水剂4种灭鼠剂对果洛藏族自治州达日县高寒草甸高原鼠兔种群密度进行了不同飞行参数投饵研究。结果表明,饵剂投放7 d和4个月后,使用无人机投放C型肉毒素颗粒剂的最优飞行高度、速度和舱门开合度为11 m、7 m/s、59%,投饵量为3.00 kg/hm^(2),而投放D型肉毒素水剂的最优飞行高度、速度和舱门开合度为14 m、11 m/s、50%,投饵量为4.50 kg/hm^(2);使用无人机投放C型肉毒素水剂的最优飞行高度、速度和舱门开合度为17m、7 m/s、41%,最优投饵量为3.00 kg/hm^(2),投放雷公藤颗粒剂的最优飞行高度、速度和开合度为17 m、9 m/s、68%,投饵量为3.38 kg/hm^(2);使用无人机投放C型肉毒素颗粒剂的防治效果(92.67%)高于投放D型肉毒素水剂(89.60%)、C型肉毒素水剂(88.19%)和雷公藤颗粒剂(79.28%)。综合评估无人机投饵的防效和药物成本,建议在高原鼠兔极度危害区采用无人机投放C型肉毒素颗粒剂进行防控,迅速降低其种群密度,而在轻中度危害区采用无人机投放雷公藤颗粒剂,这样既降低了高原鼠兔的种群密度,也避免了由于C型肉毒素等灭鼠剂的“种群清除式”灭杀而导致的食物链失衡。

甲醇制烯烃装置再生立管存在的问题及解决措施

甲醇制烯烃(MTO)装置催化剂循环回路的下行流动部分是再生立管,操作复杂性在于立管内催化剂的流态受多种因素影响。某0.60 Mt/a MTO装置投产运行7年,期间一直存在再生立管催化剂输送下料不畅的问题,反再两器运行参数波动幅度宽,工艺工况复杂多变,无法实现100%自控率,操作人员劳动强度大,产品收率降低,能耗、剂耗增加。根据现有调节措施和临时故障处理方法,只能通过调整再生立管松动风来维持短暂立管正常下料。从再生立管上下串联设备影响、再生立管整体设计、介质流化状态、工艺操作等方面出发,对再生立管生产运行瓶颈产生的原因进行分析,确定影响再生立管高效运行的症结所在。根据问题的剖析提出改进建议,为再生立管后续升级改造提供合理的理论支持和指导判断。

液相色谱-串联质谱法测定鱼饵中地西泮的不确定度评定

试验为评定液相色谱-串联质谱法测定鱼饵中地西泮含量的不确定度。试验通过建立数学模型分析不同来源的不确定度,评定各不确定度分量。结果显示,测量结果的相对标准不确定度为4.55%,相对扩展的不确定度为9.10%,样品中地西泮含量为(23.821±2.168)μg/kg(K=2)。研究表明,鱼饵中地西泮含量的测量不确定度主要源于试样重复测量、标准溶液配制和试样称量。