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51.
Landscape-ecological mapping of the Netherlands   总被引:1,自引:0,他引:1  
The Landscape-ecological Mapping of the Netherlands project (LMN project) started in 1983 with the aim of establishing a landscape-ecological database for use in developing and evaluating national land-use plans. The project, working with grid cells of 1 km2, has four working objectives: a) development of mapping potential for basic landscape-ecological data, b) assessment of susceptibility to interventions, c) evaluation of significance for nature conservation and d) production of vulnerability maps, as a combination of susceptibility and significance. In addition to information on soil, groundwater, ecotopes, flora and fauna, the database also incorporates information on physiographical features and entire landscapes. The resulting database is a geographic information system (GIS). This article describes the second phase of the project (1985–1989), covering the Randstad area, and focusses on the methods and the applications potential of the database.  相似文献   
52.
An intravenous bile acid loading test was performed on 16 goats using various dosages and sampling protocols. A recently developed enzymatic bile acid assay provided an economical and technologically simple method for bile acid analysis. Intravenous injection of bile salts into goats was well tolerated. Clearance times were rapid. A protocol for performance of the test was suggested and a practical reference range for T 1/2 clearance of 4+/-1 minute was determined. Further investigations of this test in the assessment of liver function in the ruminant appear warranted.  相似文献   
53.
In a retrospective study, 1538 strains of -haemolysin-producing Staphylococcus species isolated from dermatitis in dogs at three veterinary clinical microbiology laboratories in Norway during 1986–87 and 1993–94 were investigated for their antimicrobial susceptibility. None of the strains was resistant to cloxacillin, cephalexin or the quinolones enrofloxacin and ciprofloxacin. More than 96% of the strains were susceptible to trimethoprim-sulphonamide, bacitracin and fucidic acid. Between 67% and 89% of the strains were susceptible to erythromycin, lincosamides, tetracycline, neomycin and chloramphenicol. Only 37.9% of the strains were susceptible to penicillin. The frequency of penicillin resistance increased significantly between the first and second periods, from 46.0% to 58.6%. The frequency of resistance to lincomycin, clindamycin and erythromycin also increased significantly between the first and second periods, from 3.0%, 2.1% and 3.3% to 25.5%, 19.5% and 24.8%, respectively. A moderate increase in resistance to tetracycline was also noted, from 20.4% in the first to 27.6% in the second period. On the other hand, the frequency of resistance to trimethoprim-sulphonamide decreased significantly from 4.1% in the first to 0.9% in the second period. Many different resistance patterns were observed in each period. However, the proportion of multiresistant strains increased from 2.1% in the first to 10.2% in the second period. There was a decrease in resistance to the combination of trimethoprim-sulphonamide and penicillin from the first to the second period. Resistance to the combination of lincosamides and pencillin increased. For the combinations penicillin-tetracycline-lincosamides, pencillin-lincosamides-erythromycin, and pencillin-tetracycline-lincosamides-erythromycin, there was a striking increase in resistance between the first and the second periods.Abbreviations CVL Central Veterinary Laboratory - NCVM Norwegian College of Veterinary Medicine - NVL Norwegian Veterinary Laboratory  相似文献   
54.
A study of the basic reaction in neutralization of virus (V) by virus-neutralizing antibody (VNA) was performed with infectious bovine rhinotracheitis virus and serum collected from naturally and experimentally infected cattle after the primary immunization phase. In constant-virus/varying-serum neutralization tests a direct proportionality between VNA titer and length of preincubation was observed and found to be in accordance with basic laws of neutralization. A deviation from this direct proportionality, which was partly attributed to the presence of a dissociable V-VNA complex, was seen with relatively short preincubation. Expressing a relationship between VNA titer, length of preincubation, and virus dose under conditions where a dissociable V-VNA complex can be ignored, a log. VNA/log. V equivalence factor of neutralization was introduced. A linear relationship was found between VNA titer, taken logarithmically, and preincubation temperature. A rise in temperature by 10°C gave an increase in VNA titer of approx. 1.2 in log2. Formulae are presented for the neutralization rate factor corrected for a demonstrated invalidity of the percentage law, and for the relation between the neutralization rate factor and VNA titer. It is concluded that the results presented have elucidated the possibilities of improving the sensitivity of neutralization tests.  相似文献   
55.
Pot experiments were conducted to evaluate the level of imazamox tolerance in five red rice ( Oryza sativa L.) and four barnyardgrass (three Echinochloa crus-galli (L.) Beauv. and one Echinochloa oryzoides (Ard.) Fritch) morphologically distinct biotypes collected from rice fields in northern Greece. The susceptibility of barnyardgrass biotypes to propanil was also studied. Red rice biotypes were not controlled by imazamox applied at 40 g ha−1. In contrast, 80 g imazamox ha−1 provided 56–84% red rice control (averaged across shoot number and fresh weight reduction). Not all barnyardgrass biotypes were susceptible to imazamox applied postemergence. However, propanil applied at 2.6 kg ha −1 controlled the E. crus-galli biotypes well, but propanil applied at rates of 2.6 and 5.2 kg ha −1 was not effective in reducing the shoot number and fresh weight of the E. oryzoides biotype. Propanil applied at 10.4 kg ha −1 reduced the shoot number and fresh weight of this biotype by 78 and 85%, respectively. In most cases, a linear equation ( y  = % of control, x  = g ha−1) provided the best fit for regressions between red rice or barnyardgrass shoot number or fresh weight and imazamox rates. The results of this study suggest that postemergence application of imazamox is not effective against all red rice and barnyardgrass biotypes found in the rice fields of Greece and that significant variability regarding herbicide efficacy among biotypes might exist.  相似文献   
56.
选择国家指定的两个厂家生产的禽流感灭活疫苗(H5亚型,N28株)进行无母源抗体来航鸡的免疫试验.通过鸡免疫后血凝抑制(HI)抗体的动态性检测,对两个疫苗的免疫效果进行了观察.研究结果表明,两个疫苗均具有良好的免疫效果,但也存在一定程度的差异;加强免疫可以明显提高抗体水平,延长免疫保护时间.  相似文献   
57.
A rapid resistance/susceptibility test for Peronospora parasitica (downy mildew) was established by inoculating leaf-disks of four Brassica oleracea accessions. Several conditions were tested: disk disinfection or not, agar medium with or without nutrients and with 50 or 100 ppm of benzimidazole. Using disinfected disks placed on agar (no nutrient and benzimidazole at 50 or 100 ppm), the responses of leaf-disks to four isolates were similar to those obtained using the classical cotyledon test, whereas undesired contaminations occurred in all other conditions. The possible effect of the particular leaf used for obtaining the disks was also studied. In each incompatible interaction tested, disks were resistant whatever the leaf used. In compatible interactions, susceptible phenotypes were observed on disks derived from the six lowest leaves, but disks from upper leaves were resistant. The genetic basis of resistance in a F1 hybrid broccoli was assessed, by testing six isolates on an F2 population derived from this hybrid. The cotyledon test only allows inoculation of two isolates per seedling, whereas many isolates can be tested on each plant by using leaf-disks. The segregation of the resistance to each of the six isolates was analysed: two dominant genes (tightly linked) control resistance to all isolates (one to five isolates; the other to only one isolate).  相似文献   
58.
研究表明,金耳(Tremella aurantialba)液体发酵最适培养基组成为玉米粉2%,蔗糖3%,酵母膏0.1%,KH2PO40.1%,MgSO40.05%;培养基最佳初始pH、250mL三角瓶装量、接种量、种子菌龄分别是3.5、80mL、10%和120h;用10L发酵罐发酵时,最佳培养条件是种子种龄144h、28℃、接种量10%、通风量2.5L/min。  相似文献   
59.
狂犬病毒中和试验的病毒回归试验表明,病毒攻毒液的实际剂量与理论剂量不完全一致.建议在新版<中华人民共和国兽用生物制品质量标准>中增加对病毒攻毒实际剂量范围的规定,以使结果的判定更为合理.  相似文献   
60.
参照<中国兽药典>二○○○年版一部附录细菌内毒素检查法,研究了注射用盐酸土霉素对细菌内毒素检测的干扰情况,确定0.312 5 mg/mL浓度的供试品溶液对检测无干扰作用,建立了注射用盐酸土霉素的细菌内毒素限量检查方法.  相似文献   
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