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31.
Summary A laboratory method was developed for colour-marking different food types ingested by several slightly pigmented or unpigmented species of Collembola. After feeding Collembola on food marked with food-colouring, the gut contents of the animals appeared coloured. Thus, it was possible to accurately relate the tested animals to the differently stained types of food, irrespective of the location of the animals at the moment of observation.Dedicated to the late Prof. Dr. W. Kühnelt 相似文献
32.
The current diagnostic procedures for Q fever are discussed, especially isolation and propagation of Coxiella burnetii in BGM cell cultures, detection of antigen by an enzyme immunoassay using a biotinylated monoclonal antibody and the polymerase chain reaction (PCR). The latter is of special importance for differentiation of isolates. 相似文献
33.
34.
D Thiele C L?mmler R Sting H Krauss 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1991,38(1):11-16
Purification of a murine IgG3 monoclonal antibody (Mab 22) directed against an epitope of Chlamydia-specific lipopolysaccharide by affinity chromatography on recently described solid phase IgG Fc-receptors from Streptococcus dysgalactiae is reported. SDS-PAGE studies revealed the purity of the eluted antibody. The purified Mab 22 was characterized by determination of class, subclass and light chain-type, and by dot tests and immunoblot analysis. 相似文献
35.
Mammalian metallothionein is functional in yeast 总被引：11，自引：0，他引：11
36.
D Thiele 《Tier?rztliche Praxis》1991,19(6):605-607
Different vaccines used against chlamydial abortion in sheep are described. Problems associated with insufficient immunity after vaccination are discussed. Reasons for failure of certain vaccine preparations are addressed. Finally new developments in vaccine production are introduced which might be useful in solving problems still existing in the prevention of chlamydial abortion in sheep by vaccination. 相似文献
37.
Context
The relative importance of habitat area and connectivity for species richness is often unknown. Connectivity effects may be confounded with area effects or they may be of minor importance as posited by the habitat-amount hypothesis.Objectives
We studied effects of habitat area and connectivity of linear landscape elements for plant species richness at plot level. We hypothesized that connectivity of linear landscape elements, assessed by resistance distance, has a positive effect on species richness beyond the effect of area and, further, that the relative importance of connectivity varies among groups of species with different habitat preferences and dispersal syndromes.Methods
We surveyed plant species richness in 50 plots (25 m2) located on open linear landscape elements (field margins, ditches) in eight study areas of 1 km2 in agricultural landscapes of Northwest Germany. We calculated the area of linear landscape elements and assessed their connectivity using resistance distance within circular buffers (500 m) around the plots. Effects of area and connectivity on species richness were modelled with generalised linear mixed models.Results
Species richness did not increase with area. Resistance distance had significant negative effects on total richness and on the richness of typical species of grasslands and wetlands. Regarding dispersal syndromes, resistance distance had negative effects on the richness of species with short-distance, long-distance and aquatic dispersal. The significant effects of resistance distance indicated that species richness increased with connectivity of the network of linear landscape elements.Conclusions
Connectivity is more important for plant species richness in linear landscape elements than area. In particular, the richness of plant species that are dispersal limited and confined to semi-natural habitats benefits from connective networks of linear landscape elements in agricultural landscapes.38.
Cultural landscapes of Germany are patch-corridor-matrix mosaics for an invasive megaforb 总被引：1，自引：0，他引：1
Predicting the vulnerability of landscapes to both the initial colonisation and the subsequent spread of invasive species
remains a major challenge. The aim of this study was to assess the relative importance of sub-patch level factors and landscape
factors for the invasion of the megaforb Heracleum mantegazzianum. In particular, we tested which factors affect the presence in suitable habitat patches and the cover-percentage within invaded
patches. For this purpose, we used standard (logistic) regression modelling techniques. The regression analyses were based
on inventories of suitable habitat patches in 20 study areas (each 1 km2) in cultural landscapes of Germany. The cover percentage in invaded patches was independent from landscape factors, except
for patch shape, and even unsatisfactorily explained by sub-patch level factors included in the analysis (R
2 = 0.19). In contrast, presence of H. mantegazzianum was affected by both local and landscape factors. Woody habitat structure decreased the occurrence probability, whereas vicinity
to transport corridors (rivers, roads), high habitat connectivity, patch size and perimeter-area ratio of habitat patches
had positive effects. The significance of corridors and habitat connectivity shows that dispersal of H. mantegazzianum through the landscape matrix is limited. We conclude that cultural landscapes of Germany function as patch-corridor-matrix
mosaics for the spread of H. mantegazzianum. Our results highlight the importance of landscape structure and habitat configuration for invasive spread. Furthermore,
this study shows that both local and landscape factors should be incorporated into spatially explicit models to predict spatiotemporal
dynamics and equilibrium stages of plant invasions. 相似文献
39.
Richwall Michael．B．Seidel Dr．Hans-HeinrichTllide 《中国家禽》2004,26(4):50-51
世界蛋鸡总数1804年为10亿，经123年后，到1927年达20亿；33年后，至1960年达30亿；14年后，至1974年达40亿；13年后，至1987年，达40亿；12年后，至1999年，达50亿；至2003年，蛋鸡数量达到63亿。 相似文献
40.
C Fischer‐Tenhagen G Thiele W Heuwieser B‐A Tenhagen 《Reproduction in domestic animals》2010,45(3):468-472
The objective of the study was to investigate whether a treatment with hCG 4 days after AI could reduce pregnancy losses in lactating dairy cows. Cows of a dairy herd presented to the veterinarian in a fixed reproductive management protocol were treated with an Ovsynch protocol if no corpus luteum (CL) could be palpated per rectum (Group OV). Cows with a CL received cloprostenol (0.15 mg). After 2 days, these cows were treated with buserelin (0.01 mg) and received timed AI 16–20 h later (Group PG). In both treatment protocols, cows were assigned to two groups to receive 2500 IU of hCG i.v. 4 days after AI or to serve as untreated controls (Groups OV‐hCG, OV‐Control, PG‐hCG and PG‐Control). Pregnancy diagnosis was carried out 27 days after AI via ultrasonography and 39 days after AI by rectal palpation. Pregnancy losses were defined as cows being pregnant on day 27 but not pregnant on day 39 after AI. Pregnancy rate (PR) by day 27 did not differ among the four groups (35.4, 35.0, 37.0 and 38.0% for Groups OV‐hCG, OV‐Control, PG‐hCG and PG‐Control, respectively). Pregnancy losses between day 27 and day 39 after AI were smaller in hCG treated animals in summer but not in autumn and spring. Pregnancy rate by day 39 after AI was higher in PG than in OV groups, but independent of hCG‐treatment. In conclusion, treatment with hCG 4 days after AI did not significantly increase PR on 39 days after AI. A positive effect of hCG on pregnancy losses during the summer months warrants further investigation. 相似文献