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排序方式: 共有100条查询结果,搜索用时 15 毫秒
1.
Rodney D. Everett 《Biological conservation》1978,14(1):75-84
This study presents the data from part of a questionnaire survey in the Dalby Forest Area, Yorkshire, England. Of nearly 200 species mentioned, visitors hoped prior to their visit that they would see roe deer, badgers, foxes, squirrels, rabbits, pheasants, woodpeckers, kingfishers and adders, but the survey indicated that what they had in fact seen was very different. The number of times that visitors mentioned five groups of wildlife (mammals, birds, plants, trees and insects) altered with four different questions used, indicating that the degree of interaction that a visitor had with these groups varied at different physical, aesthetic and emotional levels. 相似文献
2.
M.R. Millikin G.N. Biddle T.C. Siewicki A.R. Fortner P.H. Fair 《Aquaculture (Amsterdam, Netherlands)》1980,19(2):149-161
An 18-week study was conducted to examine growth characteristics of the juvenile blue crab (Callinectes sapidus Rathbun) fed various levels of dietary protein. Hatchery raised individuals (157) of identical age (160 days) from the same gravid female were assigned to one of four dietary treatments: adult brine shrimp (Artemia salina Leach) and artificial pelleted diets containing crude protein levels of 23, 37, and 49%.Growth rate, measured as a function of mean weight and mean carapace width, indicated that brine shrimp-fed crabs were larger (P < 0.05) than crabs fed artificial pelleted diets. Also, blue crabs fed either 37 or 49% crude protein were larger than crabs fed the 23% crude protein diet. Molting frequency was greater in the brine shrimp-fed crabs than in those fed the artificial diets. No differences in growth were detected when comparing males vs. females fed the artificial diets. However, females demonstrated greater growth than males within the brine shrimp treatment. Protein concentration of freeze-dried whole blue crab carcasses was greater in brine shrimp-fed crabs than in crabs fed the artificial pelleted diets (P < 0.05). 相似文献
3.
Chae C Cheon DS Kwon D Kim O Kim B Suh J Rogers DG Everett KD Andersen AA 《Veterinary pathology》1999,36(2):133-137
Gnotobiotic piglets were inoculated intralaryngeally with swine Chlamydia trachomatis strain R33 or orally with swine C. trachmatis strain R27. Archived formalin-fixed, paraffin-embedded tissues from piglets euthanatized 4-7 days postinoculation were examined by in situ hybridization for C. trachomatis nucleic acid using a nonradioactive digoxigenin-labeled DNA probes that targeted specific ribosomal RNA or omp1 mRNA molecules of the swine C. trachomatis strains. Positive hybridization signals were detected in bronchial epithelial cells, bronchiolar epithelial cells, pneumocytes, alveolar and interstitial macrophages, and jejunal and ileal enterocytes. Chlamydia-infected cells had a strong signal that was confined to the intracytoplasmic inclusions. Positive hybridization signals were not detected in tissue sections from an uninfected control piglet or in C. psittaci-infected sheep placenta. The morphology of host cells was preserved despite the relatively high temperature required in parts of the incubation procedure. The data indicate that in situ hybridization can be used to detect swine C. trachomatis in formalin-fixed, paraffin-embedded tissue specimens. 相似文献
4.
5.
The development and survival of the eggs of Nematodirus filicollis placed on grass plots over a period of a year were studied. Development took place at every season although it was more rapid in the warmer months. Yields of larvae were highest from eggs placed outside during February, March and April. Larvae persisted for two to two and a half years after eggs were placed on the pastures. The extraordinary persistence of the eggs and larvae of N filicollis makes control of the parasite difficult. 相似文献
6.
Reclassification of an isolate of Guignardia citricarpa from New Zealand as Guignardia mangiferae by sequence analysis 总被引:3,自引:0,他引:3
Citrus black spot was recorded as present in New Zealand in international databases on the basis of one isolate (ICMP 8336) identified by morphological features as Guignardia citricarpa . This isolate was from a soft rot, not a typical symptom of citrus black spot, on a Seminole tangerine fruit grown in the northern region of New Zealand. Sequence analysis of the internal transcribed spacer (ITS) region (ITS1, 5·8S and ITS2) showed that this isolate was 99% identical to the ITS region of G. mangiferae , a closely related saprotroph. Despite climatic conditions being suitable for this disease, citrus black spot symptoms have never been seen on citrus fruits grown in New Zealand. Thus the absence of symptoms on citrus in New Zealand is probably because G. citricarpa is not present. On the basis of these results, the record of citrus black spot occurring in New Zealand should be re-examined. 相似文献
7.
F. Widén H. Everett S. Blome J. Fernandez Pinero Å. Uttenthal M. Cortey T. von Rosen M. Tignon L. Liu 《Research in veterinary science》2014
Classical swine fever is one of the most important infectious diseases for the pig industry worldwide due to its economic impact. Vaccination is an effective means to control disease, however within the EU its regular use is banned owing to the inability to differentiate infected and vaccinated animals, the so called DIVA principle. This inability complicates monitoring of disease and stops international trade thereby limiting use of the vaccine in many regions. The C-strain vaccine is safe to use and gives good protection. It is licensed for emergency vaccination in the EU in event of an outbreak. Two genetic assays that can distinguish between wild type virus and C-strain vaccines have recently been developed. Here the results from a comparison of these two real-time RT-PCR assays in an interlaboratory exercise are presented. Both assays showed similar performance. 相似文献
8.
9.
Neuroleptic-induced decrease in plasma homovanillic acid and antipsychotic activity in schizophrenic patients 总被引:3,自引:0,他引:3
D Pickar R Labarca M Linnoila A Roy D Hommer D Everett S M Paul 《Science (New York, N.Y.)》1984,225(4665):954-957
Plasma-free homovanillic acid, a major metabolite of dopamine, was measured in chronically ill schizophrenic patients both before and during treatment with the antipsychotic phenothiazine, fluphenazine. Neuroleptic treatment was associated with a significant time-dependent decrease in plasma homovanillic acid from pretreatment values, which were significantly elevated when compared with those of age- and sex-matched healthy control subjects. Further, both the absolute concentrations as well as the neuroleptic-induced reductions in plasma homovanillic acid determined over 5 weeks of neuroleptic treatment were statistically significantly correlated with ratings of psychosis and improvement in psychosis, respectively. These findings suggest that the delayed effects of neuroleptic agents on presynaptic dopamine activity may more closely parallel their therapeutic actions than do their immediate effects in blocking postsynaptic dopamine receptors and that a decrease in dopamine "turnover" may be responsible for their antipsychotic effects. 相似文献
10.
Marilyn Holly Carla A. Kirts Yvonne Everett Jan L. Flora David O. Hansen Cornelia Butler Flora John A. Hayward David Haenke Alessandro Bonanno 《Agriculture and Human Values》1988,5(4):57-78
Marilyn Holly is an Associate Professor of Philosophy at the University of Florida. Her special interests include political philosophy, ethics and ecology, Jungian thought, and Native American spirituality in its relation to the environment. She is currently at work on a monograph-length piece on the latter topic. She has taught an undergraduate course in ethics and ecology, and plans to do so again. The following essay emerged from her search for a suitable text for such a course. 相似文献