早熟和特早熟桃胚珠培养研究

本文以自然授粉的‘春蕾’、‘沪017’、‘布目早生’、‘1-4-8’、‘7-6-9’的胚珠为试材,研究了早熟和特早熟桃胚珠培养胚成苗的有关影响因素。本试验5个品种(品系)的结果表明,桃品种或品系的果实生育期愈短,胚珠培养胚的成苗率愈高,特早熟桃‘春蕾’花后48天的胚珠培养在改良S H培养基附加BA1.0mg/1 IAA1.0mg/1上30天,将长大的幼胚转移至TM培养基上,胚的成苗率达75％。此外,作者对胚珠培养技术在桃育种中的应用范围及其培养程序开展了讨论。     

极早熟长豇豆新品种成豇3号的选育

成豇3号豇豆是地方品种红嘴燕与另一引进品种杂交，并通过系统选育而成的常规品种。该品种极早熟，抗逆性强，比对照之豇28-2早熟7～10d(天)。商品荚浅绿色，尖端略呈暗红色。商品性优，质脆，做泡豇豆尤佳。一般每667m2产量1548kg，高产的可达3000kg，比对照之豇28-2增产13.36%。     

猴丰1号新菌株的选育及其酯酶同工酶分析

采用子实体组织分离与系统筛选法,从福建猴头的变异株中选育出了定名为“猴丰1号”的新菌株。该菌株菌丝体生长势强,发菌迅速;子实休菇形大,产量高。鲜菇产量比出发株福建猴头增加69.3％,比著名的常山99菌株增加16.8％。酯酶同工酶分析显示:猴丰1号的酯酶谱型与福建猴头相似,但有1条酶带发生了变异。由此说明,它确是源于福建猴头的自然变异株。     

高羊茅和狗牙根草坪草品种在重庆地区的引种试验

引自百绿集团的6个草坪草品种,在重庆地区进行2年的坪用性状评价。结果表明,供试品种在该地区均可终年生长。5个高羊茅品种中以Vegas表现最好,叶色浓绿,生长速度适中,盖度居供试品种之首,对该区高温高湿和高温干旱2个越夏因子均可适应;其次为Barlexas。狗牙根BarCd8USAI耐高温干旱,抗病性强,茎细叶窄,但叶色偏淡,冬季停止生长早,早春生长速度缓慢。     

草地早熟禾新品种特异性、一致性和稳定性测试指南初报

在系统调研国内外文献,广泛收集草地早熟禾种质,连续2年温室幼苗性状评估,连续3年田间性状评价和广泛征求专家意见的基础上,首次编制了我国草地早熟禾特异性、一致性和稳定性(DUS)测试指南。指南在形式与主要内容上,与国际植物新品种保护联盟(UPOV)的草地早熟禾测试指南相协调,包括测试的总体技术要求、性状表、性状解释和技术问卷4部分;在性状与标样品种确定上主要参照了UPOV和日本的测试指南。     

鸡骨型白血病免疫琼扩与放射摄片诊断的比较

为了探索特异性免疫学诊断方法对鸡骨型白血病(OP)的检测效果。用双盲法分批采样同时进行羽髓琼脂扩散试验和胫骨X线摄片检查对比,共检834只鸡(433羽属天然自发OP鸡群,401羽属人工诱发实验鸡群)。结果羽髓琼扩试验的OP阳性检出率为3．48％(29／834：)。阳性病理符合率为75．86％(22／29)。阳性误诊(假阳性)率24．13％(7／29),阴性误诊(假阴性)率36．15％(291／805)。而X线摄片检查的OP阳性检出率为38．37％(320／834)。X线阳性完全可获病理组织学证实,不存在假阳性或假阴性。把禽白血病羽髓琼扩试验试用于检测鸡骨型白血病尚属初次报道,其阳性检出率低而误诊率高,尚不宜作OP检测手段。放射摄片诊断的阳性检出率高而误诊率低,可快速诊断,故适用于OP检疫。     

Antegrade pyelography for suspected ureteral obstruction in cats: 11 cases (1995-2001)

OBJECTIVE: o determine sensitivity and specificity of radiography, ultrasonography, and antegrade pyelography for detection of ureteral obstructions in cats. DESIGN: Retrospective study. ANIMALS: 11 cats. PROCEDURE: Medical records of cats that had radiography, ultrasonography, and antegrade pyelography performed for suspected ureteral obstructions were examined. Ultrasound-guided pyelocentesis and fluoroscopic-assisted antegrade pyelography were performed on 18 kidneys in 11 cats. Obstructive ureteral lesions were confirmed in all cats by surgical or necropsy examination. Sensitivity and specificity of survey radiography, ultrasonography, and antegrade pyelography for identification of ureteral obstructions were calculated. Surgical or necropsy findings were used as the standard for comparison. RESULTS: All cats were azotemic. Mean +/- SD serum creatinine and BUN concentrations were 10.2 +/- 6.1 and 149 +/- 82 mg/dL, respectively. Fifteen of 18 ureters were found to be obstructed at surgery or necropsy. Sensitivity and specificity were 60 and 100% for radiography and 100 and 33% for ultrasonography, respectively, in identification of ureteral obstructions. Leakage of contrast material developed in 8 of 18 kidneys during antegrade pyelography and prevented diagnostic interpretation in 5 of 18 studies. For the 13 diagnostic studies, specificity and sensitivity were 100% by use of the antegrade pyelography technique. Correct identification of the anatomic location of the ureteral obstruction was obtained in 100% of diagnostic antegrade pyelography studies and in 60% of radiography or ultrasonography studies. CONCLUSIONS AND CLINICAL RELEVANCE: Antegrade pyelography can be a useful alternative in the diagnosis and localization of ureteral obstructions in azotemic cats, although leakage of contrast material may prevent interpretation of the study.     

21世纪教育发展趋势展望

传统教育面临着后现代教育和网络迅猛发展的严峻考验。时代的发展和变革也要求教育的改革。了解后现代教育的意义和重要性能 ,促使“精英教育”、“制度化教育”向适应时代和社会发展需要的“全民教育”、“终身教育”转化     

Recurrent and persistent urinary tract infections in dogs: 383 cases (1969-1995)

Laboratory records of bacterial urine cultures from 383 dogs with recurrent or persistent urinary tract infections (UTI) diagnosed at the University of California Veterinary Medical Teaching Hospital (VMTH) between 1969 and 1995 were reviewed retrospectively to characterize the bacteria involved and their association with age, gender, and breed of dogs affected. Sixty-eight breeds and a mixed-breed group were represented. Escherichia coli was the most common isolate, although mixed-bacterial infections were seen in 58% of the female and 55% of the male dogs. Recurrent and persistent UTI were most prevalent in middle-aged to older German shepherd dogs, miniature/toy poodles, and Labrador retrievers, with no apparent sex predilection. Criteria fitting recurrent and persistent UTI were present in 0.3% of all dogs seen at the VMTH during this 26-year period.     

氧气对低地鸡蛋胚胎死亡和孵化率的影响

通过模拟常压低氧和高海拔增氧孵化试验，研究了氧气浓度对低地良种鸡蛋胚胎死亡率和孵化率的影响。死亡胚胎的分布用2阶段增长模型分析。模拟2900m海拔常压低氧孵化增加了胚胎后期死亡率，使孵化率降低到接近2900m海拔实际孵化率水平；2900m海拔全期增氧孵化可以有效降低前期和后期胚胎死亡率，大大提高孵化率；阶段增氧孵化也能不同程度提高孵化率，改变胚胎死亡分布，其中效果最好的为前期增氧组。结果说明低氧是影响2900m海拔鸡蛋孵化的最主要因素。