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1.
萧氏松茎象幼虫的空间分布型和抽样技术   总被引:15,自引:0,他引:15  
萧氏松茎象Hylobitelus xiaoi Zhang是我国近年来发现的危害松林的新害虫。该文利用1wao等7种方法对萧氏松茎象幼虫的空间分布型进行了测定。结果表明,萧氏松茎象幼虫在林间呈聚集分布,且符合负二项分布,由此得出了林间理论抽样数公式,其抽样方式以对角线最佳;其有虫株率与平均虫口密度之间的关系可用冥函数曲线方程:Y=2.916X^0.887来进行描述。  相似文献   

2.
《环境昆虫学报》2013,35(4):435-440
为摸清萧氏松茎象Hylobitelus xiaoi zhang受害松林的环境因子特征,应用林地环境因子常规观测方法进行观测,结果表明:8月份受害松林地面平均光照强度、地面温度、距地表20 cm高处温度、5 cm深处土壤温度、70 cm高处蒸发量分别为3748 lx、254℃、271℃、255℃、16 mm,分别比健康松林低948%、70%、46%、59%、273%,受害松林在距地表20 cm高处空气相对湿度为858%,比健康松林高71%。由实验得知,萧氏松茎象受害松林的光照强度、地面温度、空气温度、土壤温度、蒸发量均比健康松林低,空气相对湿度比健康松林高,距地表越近,这一差异就越明显。两类林分中的光照强度、空气温度、土壤温度、空气相对湿度4因子均存在明显差异,是影响萧氏松茎象发生的重要因素。  相似文献   

3.
萧氏松茎象危害与松树松脂量关系研究初报   总被引:6,自引:1,他引:5  
萧氏松茎象HylobitelusxiaoiZhang是近年来暴发性松树害虫 ,主要危害 3种松树 :湿地松 (PinuselliottiiEngelm)、火炬松 (P .taeda)、马尾松 (P .massoniaanaLamb) ,其中以湿地松受害最为严重。为明确萧氏松茎象的危害与松脂流量的关系 ,作者对萧氏松茎象危害前后 3种松树 (湿地松、马尾松、火炬松 )松脂流量变化进行了研究。结果显示 ,在松树受害植株和未受害植株间松脂总流量间存在一定差异 ,其中以马尾松松脂流量变化最大 ,对受害株和未受害株松脂流量t-测验 ,差异达到显著水平 ;而湿地松和火炬松松脂总流量在受害植株和未受害植株间没有显著差异。对上述 3种松树松脂流量随时序动态变化的分析显示 ,松脂流量在 1年中以 5月到 6月之间为松脂流量高峰期 ,此后逐渐下降 ,到 3月中旬以后松脂流量又开始上升。就松脂流量时序动态而言 ,萧氏松茎象为害对马尾松松脂流量影响最大 ,对其它2个松树影响不明显。另外 ,不同松树树种在松脂流量及其时序动态上也存在一定差异 ,其中以马尾松脂流量较高。  相似文献   

4.
三种生物源农药对桃树蚜虫的防治效果研究   总被引:1,自引:0,他引:1  
为筛选生产上防治桃树蚜虫的生物源农药,开展了1.5%除虫菊素水剂、0.3%苦参碱水剂和5%桉油精可溶液剂对桃树蚜虫的田间防效试验。结果表明,3种生物源农药中以0.3%苦参碱水剂防治效果最好,药后1 d防效为70.12%,药后7 d防效为91.96%,与对照药剂70%吡虫啉水分散粒剂防效相当,具有较好的速效性和持效性。苦参碱对桃树安全,是防治桃蚜的理想药剂,生产上推荐使用浓度为1 000倍液。  相似文献   

5.
本参照国内外专家对有害生物的危险性定量分析方法,结合福建省森林资源状况和病虫害发生防治等情况,建立适用于福建省的有害生物潜在危险性的定量分析评价指标体系,并据此对松突圆蚧,红脂大小蠹,萧氏松茎象,湿地松粉蚧,日本松干蚧等5种松树害虫,对福建省的潜在危险性进行了定量分析和评价,结果表明松突圆蚧,萧氏松芪象,日本松干蚧为高度危险的害虫,红脂大小囊,湿地松粉蚧属中度但接近高度危险的害虫,并据此提出了相应的风险管理措施。  相似文献   

6.
【目的】为解决当前苹果园二斑叶螨Tetranychus urticae抗药性高、防治效果差、用药量大的问题,评价当前登记药剂及果园正在使用的药剂对二斑叶螨的防治效果。【方法】采用室内生测的方法比较了10种登记药剂,9种果园正在使用的药剂对二斑叶螨的毒力效果。【结果】选用的登记药剂中,80%的药剂对二斑叶螨效果差,甚至失去控制作用,防治效果低于66.67%,仅双甲脒、阿维菌素48 h防效在92.68%以上;果园常用药剂螺螨酯、虫酰肼、噻虫啉对二斑叶螨均表现出很好的防治效果,48 h防效达到84.09%-100%。【结论】目前80%以上的登记单剂药剂对二斑叶螨失去了防控效果,这是果园二斑叶螨防效差的主要原因,常用药剂螺螨酯、虫酰肼、噻虫啉等对二斑叶螨防效好。建议增加高效药剂登记或更换防治药剂,保证对二斑叶螨的防效,降低果园用药量,提高果园用药系统的精准性。二斑叶螨防治不能仅依赖化学药剂,要充分发挥果园生态系统的自然控害功能,延缓抗药性发展。  相似文献   

7.
30%强力杀蚧防治梅园朝鲜球坚蚧试验   总被引:4,自引:0,他引:4  
黄保宏  王从汉 《昆虫知识》2005,42(5):575-577
30%强力杀蚧(Omethoate)微乳剂防治梅园朝鲜球坚蚧DidesmococcuskoreanusBorchs试验结果表明:800,1200倍液药后1~7d的防效均保持在94.5%以上,击倒力强,杀蚧效果快;药效期长,药后14d,防效仍达99%以上;其600,800和1200倍液之间防效差异不明显。600,800和1200倍液的防治效果与25%蚧死净乳油在药后3,5,7,14d的防效有显著差异,25%蚧死净乳油的持效时间均较短,药后3d防效就陆续下降,分别从89.92%降到88.56,81.41%和61.82%。而与40%杀扑磷(速扑杀)乳油相比其防治效果之间无显著差异。30%强力杀蚧微乳剂具有作用速度快,持效期长、对青梅安全性高,防治成本底的特点。  相似文献   

8.
在红火蚁发生区域选农田、山坡地、绿化带、草坪等4个不同生境地块,采用灭蚁威毒饵进行防治试验,并对其药效进行调查。结果显示,药后10d,灭蚁威对红火蚁蚁巢的防效较差,且表现出不同生境而有所差异;但在药后35d时,其对蚁巢和工蚁的校正防效均在95%以上,表现出良好的防治效果。本试验结果表明,灭蚁威的药效需一个月后才能充分发挥;在红火蚁发生区,对不同的生境均可采用灭蚁威饵剂进行防治。  相似文献   

9.
萧氏松茎象幼虫龄数的估测   总被引:4,自引:0,他引:4  
室内和林间调查的结果表明 ,萧氏松茎象HylobitelusxiaoiZhang幼虫期为 5~ 7龄。该虫在林间以老熟幼虫的前 1龄幼虫 ,即以第 4~ 6龄幼虫越冬 ,其中以 5~ 6龄幼虫为主 ,4龄幼虫仅占少数  相似文献   

10.
萧氏松茎象的早期寄主研究   总被引:11,自引:0,他引:11  
本文以调查的事实材料为基础,对萧氏松茎象的早期寄主进行了研究,说明该虫最先在马尾松树种上发生,而后逐渐蔓延到从国外引进的湿地松、火炬松和国外松上猖獗危害。 萧氏松茎象(HylobitelusxiaoiZhang)是江西省吉安地区 1988年发现的国外松新害虫。十多年来,该虫蔓延十分迅速,危害国外松特别严重。据1999年调查,江西省40余县(市)有分布.发生面积1万公顷以上,成为国外松的主要害虫。究竟此虫最初寄主是何树种,它为什么发展那么快呢?弄清这一问题十分重要,不仅对制订正确的防范措施,而且对研…  相似文献   

11.
Spinal stability is related to both the intrinsic stiffness of active muscle as well as neuromuscular reflex response. However, existing analyses of spinal stability ignore the role of the reflex response, focusing solely on the intrinsic muscle stiffness associated with voluntary activation patterns in the torso musculature. The goal of this study was to empirically characterize the role of reflex components of spinal stability during voluntary trunk extension exertions. Pseudorandom position perturbations of the torso and associated driving forces were recorded in 11 healthy adults. Nonlinear systems-identification analyses of the measured data provided an estimate of total systems dynamics that explained 81% of the movement variability. Proportional intrinsic response was less than zero in more than 60% of the trials, e.g. mean value of P(INT) during the 20% maximum voluntary exertion trunk extension exertions -415+/-354N/m. The negative value indicated that the intrinsic muscle stiffness was not sufficient to stabilize the spine without reflex response. Reflexes accounted for 42% of the total stabilizing trunk stiffness. Both intrinsic and reflex components of stiffness increased significantly with trunk extension effort. Results reveal that reflex dynamics are a necessary component in the stabilizing control of spinal stability.  相似文献   

12.
The aim of this paper is to present a method allowing the identification of the lame limb in trotting horses. Using a 3-D kinematic analysis system, 13 sound and 25 lame horses fitted with 4 skin markers placed on the dorsal midline of their trunk were recorded while trotting on a track in the conditions of the routine lameness examination. The vertical displacements of the trunk markers underwent Fourier analysis. Results indicated that these displacements could be represented using only the first and second harmonics. From these two harmonics, indices were then developed. The sensitivity of these indices to the different types of experimental errors was also studied. Results showed that the values of the indices of the lame horses were relatively unaffected by the experimental errors. In lame horses, these indices allowed the quantification of the degree of the lameness, the identification of lame limb with a reliability > 95% and the characterisation of the type of trunk movements. These indices could be easily implemented in a computer program to provide objective information to the clinician or to be used as a first step in the development of an expert system. Moreover, these clinical tools may also be extended to other quadrupedal or bipedal locomotions.  相似文献   

13.
摘要 目的:探讨运动想象疗法(MI)联合神经肌肉本体感觉促进术(PNF)躯干模式训练对脑卒中偏瘫患者上肢功能、步行功能和躯干控制能力的影响。方法:选取2015年1月-2019年6月期间中国人民解放军第九八三医院及中国中医科学院望京医院康复治疗中心收治的112例脑卒中偏瘫患者。根据按入院顺序编号的奇、偶数分为对照组(n=56)和研究组(n=56),对照组给予常规康复训练联合MI训练,研究组在对照组基础上联合PNF躯干模式训练,两组均干预8周。对比两组干预前、干预4周后、干预8周后的Carroll手功能评定(UEFT)、Fugl-Meyer运动功能评定(FMA)、改良的Barthel指数(mBI)、功能性步行分级(FAC)、Tinetti步态评估量表(TGA)、躯干控制能力测试(TCT)、Berg平衡功能量表(BBS)、坐-站-坐时间以及躯干前倾距离。结果:两组干预4周后、干预8周后UEFT、FMA、mBI评分逐渐升高,且研究组高于对照组(P<0.05)。两组干预4周后、干预8周后FAC、TGA评分逐渐升高,且研究组高于对照组(P<0.05)。两组干预4周后、干预8周后TCT、BBS评分逐渐升高,且研究组高于对照组(P<0.05)。两组干预4周后、干预8周后坐-站-坐时间逐渐降低,且研究组低于对照组(P<0.05),躯干前倾距离逐渐升高,且研究组高于对照组(P<0.05)。结论:MI联合PNF躯干模式训练治疗脑卒中偏瘫患者,可有效改善患者步行功能、上肢功能和躯干控制能力。  相似文献   

14.
Thermal injury results in dystropic changes in skeletal muscle and abnormal pharmacological responses to neuromuscular relaxants, each of which suggests a denervation-like phenomenon. In the rat thermal injury model we examined whether, as in denervation states, increases in nicotinic acetylcholine receptors (AChR) and hyposensitivity to d-tubocurarine (dTc) are found. While anesthetized, thermal injury was imposed to trunk only. At 10, 14, and 21 days after injury the effective doses of dTc for left gastrocnemius tension suppression to 95% of control tension (ED95) were 0.213 +/- 0.039, 0.305 +/- 0.070, and 0.214 +/- 0.032 mg/kg, respectively. These values were significantly higher (P less than 0.05) than control values (0.155 +/- 0.006 mg/kg). The AChR concentrations in the left gastrocnemius, quantitated by 125I-alpha-bungarotoxin binding, increased at 10, 14, and 21 days to 182 +/- 20% (P less than 0.001), 166 +/- 22% (P less than 0.03), and 164 +/- 18% (P less than 0.001) of control, respectively. AChR concentrations in the right gastrocnemius also increased subsequent to thermal injury. Changes in effective dose of dTc for 50 and 95% twitch suppression in the left gastrocnemius correlated significantly with changes in AChR concentrations for the same muscle (r = 0.73 and 0.81, P less than 0.001, respectively). This study confirms the hypothesis that the systemic effects of thermal injury include an increase in AChR at sites distant from thermal injury, which may account for the skeletal muscle dysfunction and aberrant responses to neuromuscular relaxants.  相似文献   

15.

Background

Body shape is a known risk factor for diabetes and mortality, but the methods estimating body shape, BMI and waist circumference are crude. We determined whether a novel body shape measure, trunk to leg volume ratio, was independently associated with diabetes and mortality.

Methods

Data from the National Health and Nutritional Examination Survey 1999–2004, a study representative of the US population, were used to generate dual-energy X-ray absorptiometry-derived trunk to leg volume ratio and determine its associations to diabetes, metabolic covariates, and mortality by BMI category, gender, and race/ethnicity group.

Results

The prevalence of pre-diabetes and diabetes increased with age, BMI, triglycerides, blood pressure, and decreased HDL level. After adjusting for covariates, the corresponding fourth to first quartile trunk to leg volume ratio odds ratios (OR) were 6.8 (95% confidence interval [CI], 4.9–9.6) for diabetes, 3.9 (95% CI, 3.0–5.2) for high triglycerides, 1.8 (95% CI, 1.6–2.1) for high blood pressure, 3.0 (95% CI, 2.4–3.8) for low HDL, 3.6 (95% CI, 2.8–4.7) for metabolic syndrome, and 1.76 (95% CI, 1.20–2.60) for mortality. Additionally, trunk to leg volume ratio was the strongest independent measure associated with diabetes (P<0.001), even after adjusting for BMI and waist circumference. Even among those with normal BMI, those in the highest quartile of trunk to leg volume ratio had a higher likelihood of death (5.5%) than those in the lowest quartile (0.2%). Overall, trunk to leg volume ratio is driven by competing mechanisms of changing adiposity and lean mass.

Conclusions

A high ratio of trunk to leg volume showed a strong association to diabetes and mortality that was independent of total and regional fat distributions. This novel body shape measure provides additional information regarding central adiposity and appendicular wasting to better stratify individuals at risk for diabetes and mortality, even among those with normal BMI.  相似文献   

16.
摘要 目的:观察负压封闭引流技术(VSD)对颈部及躯干深度烧伤植皮修复患儿生活质量和血清炎症因子的影响。方法:选取2016年4月~2020年12月期间我院接收的颈部及躯干深度烧伤患儿70例,采用计算机系统随机编号的方式将患儿分为2组,分别为对照组35例和实验组35例。对照组患儿进行游离植皮后常规包扎处理,实验组患儿进行游离植皮后在VSD下进行包扎处理。考察两组患儿疗效指标。术前、出院后30 d采用36项健康调查简表(SF-36)评估所有患儿的生活质量。术前、术后7d观察两组炎症因子水平变化。记录两组患儿并发症发生率。结果:实验组术后7 d植皮成功率高于对照组,术后住院天数、术后创面愈合时间短于对照组,术后换药次数少于对照组(P<0.05)。出院后30 d,两组患儿生理功能(PF)、总体健康 (GH)、生理职能(RP)、活力 (VT)、躯体疼痛(BP)、情感职能 (RE)、社会功能(SF)及精神健康(MH)评分均较术前升高,且实验组高于对照组(P<0.05)。术后7 d,两组患儿血清白介素-6(IL-6)、C 反应蛋白(CRP)和降钙素原(PCT)水平均较术前降低,且实验组低于对照组(P<0.05)。实验组的并发症总发生率低于对照组(P<0.05)。结论:针对颈部及躯干深度烧伤植皮修复患儿,在VSD下进行包扎处理,可提高植皮成功率,缩短住院天数及创面愈合时间,减少换药次数,降低并发症发生率,还可提高患儿生活质量及减轻机体炎性反应,值得临床借鉴。  相似文献   

17.
Strength and conditioning professionals, as well as coaches, have emphasized the importance of training the trunk and the benefits it may have on sport performance and reducing the potential for injury. However, no data on the efficacy of trunk training support such claims. The purpose of this study was to examine the maximum differential trunk rotation and maximum angular velocities of the pelvis and upper torso of participants while they performed 4 trunk exercises (seated band rotations, cross-overs, medicine ball throws, and twisters) and compare these trunk exercise kinematics with the trunk kinematics demonstrated in actual throwing performance. Nine NCAA Division I baseball players participated in this study. Each participant's trunk kinematics was analyzed while he performed 5 repetitions of each exercise in both dominant and nondominant rotational directions. Results indicated maximum differentiated rotation in all 4 trunk exercises was similar to maximum differentiated rotation (approximately 50-60 degrees) demonstrated in throwing performance. Maximum angular velocities of the pelvis and upper torso in the trunk exercises were appreciably slower (approximately 50% or less) than the angular velocities demonstrated during throwing performance. Incorporating trunk training exercises that demonstrate sufficient trunk ranges of motion and velocities into a strength and conditioning program may help to increase ball velocity and/or decrease the risk injury.  相似文献   

18.
Objective To compare routine replacement of intravenous peripheral catheters with replacement only when clinically indicated.Design Randomised controlled trial.Setting Tertiary hospital in Australia.Participants 755 medical and surgical patients: 379 allocated to catheter replacement only when clinically indicated and 376 allocated to routine care of catheter (control group).Main outcome measure A composite measure of catheter failure resulting from phlebitis or infiltration.Results Catheters were removed because of phlebitis or infiltration from 123 of 376 (33%) patients in the control group compared with 143 of 379 (38%) patients in the intervention group; the difference was not significant (relative risk 1.15, 95% confidence interval 0.95 to 1.40). When the analysis was based on failure per 1000 device days (number of failures divided by number of days catheterised, divided by 1000), no difference could be detected between the groups (relative risk 0.98, 0.78 to 1.24). Infusion related costs were higher in the control group (mean $A41.02; £19.71; €24.80; $38.55) than intervention group ($A36.40). The rate of phlebitis in both groups was low (4% in intervention group, 3% in control group).Conclusion Replacing peripheral intravenous catheters when clinically indicated has no effect on the incidence of failure, based on a composite measure of phlebitis or infiltration. Larger trials are needed to test this finding using phlebitis alone as a more clinically meaningful outcome.Registration number Australian New Zealand Clinical Trials Registry ACTRN12605000147684.  相似文献   

19.
为了综合评价常用杀螨剂对荔枝叶螨Oligonychus litchii的室内毒力,在室内分别采用Potter喷雾法、浸叶碟法和浸叶法测定了5种常用杀螨剂对荔枝叶螨成螨、卵和若螨的毒力,并测定了5种杀螨剂对荔枝叶螨的田间防效。室内毒力结果表明:哒螨灵、阿维菌素对荔枝叶螨成螨和若螨有较高的毒力,联苯肼酯对成螨和若螨的毒力较低,而螺螨酯和乙螨唑对成螨基本无活性,对若螨有一定的毒力;5种杀螨剂对卵的毒力大小依次为乙螨唑螺螨酯哒螨灵阿维菌素联苯肼酯。田间防效试验中,15%哒螨灵乳油和1.8%阿维菌素乳油对荔枝叶螨的总体防效较好,药后1 d防效高于70%,药后10 d防效达100%,药后20 d防效仍在90%以上,速效性和持效性均较好;240 g/L螺螨酯悬浮剂和110 g/L乙螨唑悬浮剂对荔枝叶螨药后3 d防效均低于70%,而药后20 d的防效高于90%,说明两药剂速效性较差但持效性较好;43%联苯肼酯悬浮剂药后1、3 d防效低于阿维菌素和哒螨灵,高于螺螨酯和乙螨唑,药后15 d防效开始下降。在田间防治荔枝叶螨时,若荔枝叶螨发生早期、成螨较少时建议施用螺螨酯或乙螨唑,而荔枝叶螨种群中成螨、若螨较多时推荐施用阿维菌素、哒螨灵或联苯肼酯。  相似文献   

20.
A case control study was conducted to evaluate the significance of Neospora caninum infections in cattle in England and Wales. The prevalence of N. caninum in normally calving cattle (the control group; n = 418) and aborting cattle (n = 633) was estimated using a commercial antibody-detection ELISA. Prevalence estimates for bovine virus diarrhoea virus, infectious bovine rhinotracheitis virus and Leptospira hardjo were also obtained by serology. The prevalence of N. caninum was significantly higher (P < 0.0001) in the aborting group (18%; 95% confidence interval: 15%, 21%) than in the control group (6%; 95% confidence interval: 4%, 8%); the latter is the first estimate, to date, of the national seroprevalence of N. caninum in dairy cattle in England and Wales. Prevalence estimates for bovine virus diarrhoea virus, infectious bovine rhinotracheitis virus and L. hardjo were not found to be higher in the aborting cattle than in the control group. With N. caninum, a strong association between seropositivity and abortion was found, with seropositive cows being 3.5-times more likely to abort than seronegative cows (odds ratio = 3.49; 95% confidence interval: 2.16, 5.69). Furthermore, 12.5% of abortions in dairy cattle in England and Wales may be attributable to N. caninum, as indicated by estimation of the population aetiological fraction.  相似文献   

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