Identification ofTomato Mottle Taino Begomovirus strains in Cuban potato fields

The presence of a begomovirus in potato plants with yellow mottle symptoms was determined for the first time in Cuba. The incidence of typical begomovirus-like symptoms in potato plants in some regions of Havana province (Güira de Melena, San José de las Lajas, Güines and Boyeros) during the growing seasons from 1992 to 1998 was in general low. However, in some cultivars belonging to the National Program for Potato Genetic Improvement, the incidence reached 100%. Yield losses, determined in 1992 and 1994, ranged as high as 19% to 56.33% depending on the cultivar. Characterization of the causal agent was done by light microscopy, host range (graft and mechanical transmission), DNA hybridizations, polymerase chain reaction, and restriction fragment length polymorphism analysis. Nucleotide sequence of the amplified fragments revealed the presence ofTomato mottle Taino virus. The virus was transmittedvia tubers and has been detected in mixed infections withPotato virus X and withPotato leaf roll virus. http://www.phytoparasitica.org posting Oct. 20, 2003. The first two authors contributed equally to this work.     

昆虫病原线虫和共生细菌培养系统中噬菌体的检测

本文利用紫外照射、温度、pH、盐度诱导五株溶源性共生菌株Xenorhabdus和Photorhabdus同时测定斯氏和异小杆属线虫Steinernema carpocapsae A24,S.carpacapsae ALL,S.feltiae English,S.feltiae SN,Heterorhabditis bacterophora H06在体外培养过程中是否存在感染共生细菌的噬菌体。结果未发现噬菌斑，说明实验菌株在实验诱导条件下以及昆虫病原线虫固体培养系统中不可能诱发噬菌体的危害。     

川楝素腹腔注射对小白鼠半数致死量(LD50)的测定

用寇氏(karber)法测定了川楝素腹腔注射对小鼠的半数致死量(LD50).取90只小鼠,雌雄各半,体重(25±2)g.以10%丙二醇生理盐水为溶媒,按序贯法测出川楝素腹腔注射小鼠100%致死率;将高剂量组与低剂量组的组间剂量比设定为1.2,染毒测定其LD50.结果川楝素腹腔注射对小鼠的LD50为13.84 mg/kg,95%可信限为12.46～15.37 mg/kg.     

银条茎尖培养快繁及离体根状茎的诱导

 以银条‘二细一粗’品种为试材, 研究了蔗糖浓度、激素组合对茎尖培养和快速繁殖的影响及温度、光照、蔗糖浓度等因素对根状茎离体诱导的影响。结果表明: 茎尖培养较理想的培养基为MS + 蔗糖4 % + 6-BA 0.5 mg·L ^{- 1} + NAA 0.1 mg·L ^{- 1} , 成苗率可达74.0 %。茎尖增殖较适培养基为MS + 6-BA 3.0 mg·L ^{- 1} + NAA 0.5 mg·L ^{- 1} , 每个外植体平均可产生5.6 个芽。根状茎诱导以MS + 蔗糖10 % + 6-BA 510 mg·L ^{- 1}+ CCC 500 mg·L ^{- 1}培养基, 20 ℃全黑暗培养效果最好。     

西安白鹿塬约85OO年来土壤侵蚀研究

本文根据作者的观察和测量，对西安市白鹿塬塬区的土壤侵蚀状况进行了研究。研究表明，白鹿塬塬区确定土壤侵蚀的主要依据是土层厚度的变化，并非侵蚀面。塬区侵蚀是塬边侵蚀较强，向塬里侵蚀逐渐减弱。塬面上高地侵蚀弱，低地侵蚀强，暂时性线状流水长期汇集而成的冲沟对黄土塬区土壤的侵蚀更加强烈。气候对土壤侵蚀也有影响，冷干和温湿气候均会产生土壤侵蚀，冷干期侵蚀量比温湿期大，前者侵蚀厚度比后者大7倍多。     

Effects of fosinopril,captopril and valsartan on the expressionof tissue factor in human monocytes

AIM: To investigate the effects of angiotensin-converting enzyme inhibitors (ACEI), fosinopril, captopril and angiotensin II AT₁ antagonists, valsartan on tissue factor (TF) expression on monocytes induced by lipopolysaccharide (LPS). METHODS: Mononuclear leukocytes from normal delivered female umbilical veins were incubated with bacterial LPS in presence or absence of different ACE inhibitors .At the end of incubation, the cells were disrupted by 3 freeze-thaw cycles. TF procoagulant activity was assessed by a one-stage clotting assay. RT-PCR was used to check TF mRNA expression, and GAPDH mRNA was used for parallel assay. RESULTS and CONCLUSION: The results showed that increased expression of TF mRNA induced by LPS was inhibited by fosinopril, captopril and valsartan, respectively, and the procoagualant activity of monocytes was also reduced.     

Renal ultrasonographic evaluation in the oncilla (Leopardus tigrinus).

Ultrasonography is currently used in veterinary medicine to examine the anatomy and physiology of internal organs and to establish normal standards for exotic animal species. Specifically, the kidneys may be evaluated and measured in length, width, and height. The kidneys in 33 oncilla (Leopardus tigrinus), including 20 males and 13 females, were opportunistically located, characterized, and measured by ultrasound using a 7.5-MHz linear transducer at two different zoologic facilities in S?o Paulo, Brazil. Renal volume was calculated from these linear measurements. The mean linear measurements and volume of the right and left kidneys were not significantly different.     

日粮维生素E水平对后备种母鸡生长发育的影响

研究日粮维生素E对后备种母鸡体形、肌肉和生殖器官生长发育的影响。发现日粮维生素E水平对20周龄后备种母鸡的体重、体重均匀度、胸骨长度、胫长度、屠宰率、半净膛率、全净膛率、胸肌率、腿肌率、翅重率、腹脂率、冠高度和卵巢重量没有显著影响(P>0 05 ), 但高剂量维生素E日粮显著增加输卵管的长度和重量(P<0 05)。结果表明日粮高维生素E水平(180mg/kg) 可加速20周龄后备种母鸡输卵管的生长发育。     

Retrospective Evaluation of the Effect of Heart Rate on Survival in Dogs with Atrial Fibrillation

Background

Atrial fibrillation (AF) usually is associated with a rapid ventricular rate. The optimal heart rate (HR) during AF is unknown.

Hypothesis/Objectives

Heart rate affects survival in dogs with chronic AF.

Animals

Forty‐six dogs with AF and 24‐hour ambulatory recordings were evaluated.

Methods

Retrospective study. Holter‐derived HR variables were analyzed as follows: mean HR (meanHR, 24‐hour average), minimum HR (minHR, 1‐minute average), maximum HR (maxHR, 1‐minute average). Survival times were recorded from the time of presumed adequate rate control. The primary endpoint was all‐cause mortality. Cox proportional hazards analysis identified variables independently associated with survival; Kaplan‐Meier survival analysis estimated the median survival time of dogs with meanHR <125 bpm versus ≥125 bpm.

Results

All 46 dogs had structural heart disease; 31 of 46 had congestive heart failure (CHF), 44 of 46 received antiarrhythmic drugs. Of 15 dogs with cardiac death, 14 had CHF. Median time to all‐cause death was 524 days (Interquartile range (IQR), 76–1,037 days). MeanHR was 125 bpm (range, 62–203 bpm), minHR was 82 bpm (range, 37–163 bpm), maxHR was 217 bpm (range, 126–307 bpm). These were significantly correlated with all‐cause and cardiac‐related mortality. For every 10 bpm increase in meanHR, the risk of all‐cause mortality increased by 35% (hazard ratio, 1.35; 95% CI, 1.17–1.55; P < 0.001). Median survival time of dogs with meanHR<125 bpm (n = 23) was significantly longer (1,037 days; range, 524‐open) than meanHR ≥125 bpm (n = 23; 105 days; range, 67–267 days; P = 0.0012). Mean HR was independently associated with all‐cause and cardiovascular mortality (P < 0.003).

Conclusions and Clinical Importance

Holter‐derived meanHR affects survival in dogs with AF. Dogs with meanHR <125 bpm lived longer than those with meanHR ≥ 125 bpm.     

Use of two doses of cloprostenol in different intervals for estrus synchronization in hair sheep under tropical conditions

Tropical Animal Health and Production - This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes...