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排序方式: 共有207条查询结果,搜索用时 12 毫秒
1.
Comparison of diagnostic accuracy of laparoscopic 3 mm and 5 mm cup biopsies to wedge biopsies of canine livers
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2.
Marek Šmejkal Marie Prchalová Martin Čech Mojmír Vašek Milan Říha Tomáš Jůza Petr Blabolil Jan Kubečka 《Ecology of Freshwater Fish》2014,23(3):405-413
Fish associations with different types of littoral habitats were studied in four canyon‐shaped reservoirs in the Czech Republic in years 2010 and 2011 by gillnets. Two to three habitats per reservoir–beaches (former meadows), stump fields (former forest) and rubble slopes–were defined and sampled along the longitudinal axis of reservoirs. Effects of reservoir, habitat and locality (position along longitudinal axis) on fish biomass, abundance and species structure were tested for juvenile and adult fish separately. Hierarchical analysis of variance revealed that habitats differed significantly in fish biomass and abundance. Redundancy analysis showed that analysed environmental variables had significant influence on fish community structure. Most variability in community structure was explained by reservoir and then by combination of habitat and slope steepness. Locality position had the smallest influence on community structure. For both adult and juvenile fish total abundance and biomass, the most inhabited habitat was beaches; rubble slopes were the least inhabited. Habitat associations differed among species. Among adults, bream Abramis brama, white bream Blicca bjoerkna and roach Rutilus rutilus were associated with beaches and stump fields, whereas perch Perca fluviatilis, ruffe Gymnocephalus cernuus, asp Aspius aspius and pike Esox lucius were associated with rubble slopes. Bream, white bream, bleak Alburnus alburnus, roach, ruffe and pikeperch Sander lucioperca were associated with beaches among juveniles, whereas the only juvenile associated with rubble slopes was perch. We showed that most common species are associated with distinct habitats and also that utilisation of various littoral habitats differs in general. 相似文献
3.
Jana Rydlová David Püschel Radka Sudová Milan Gryndler Olga Mikanová Miroslav Vosátka 《植物养料与土壤学杂志》2011,174(1):128-134
This study focused on the application of native strains of arbuscular mycorrhizal fungi (AMF) and Sinorhizobium in effective crop production during reclamation of coal‐mine spoil banks. Two greenhouse experiments were conducted in spoil‐bank clay with a low dose of organic amendment to determine whether the microbial inoculation improves growth and utility qualities of two cultivars of Linum usitatissimum L. (oil and fiber flax). Inoculation with two native AMF isolates (Glomus mosseae, G. intraradices, and their mixture) significantly increased growth and shoot phosphorus (P) concentration of both flax cultivars. Inoculated fiber flax plants produced fivefold more fibers than the uninoculated ones. In oil flax, mycorrhizal inoculation significantly but quantitatively to a minor degree decreased the concentration of nonsaturated fatty acids in the seed oil. A mixture of five native Sinorhizobium sp. strains supported growth and P uptake of oil flax only in the absence of AMF. However, these beneficial effects of the bacteria were significantly lower as compared to AMF. No synergic action of Sinorhizobium strains and AMF was observed, and their interactions were often even antagonistic. Inoculation with AMF significantly decreased population density of Sinorhizobium in the soil. These results suggest that a careful selection of suitable bacterial strains is necessary to provide effective AMF combinations and maximize flax‐growth support. 相似文献
4.
5.
"Kennel cough" in dogs in animal shelters is readily transmissible, reduces adoption rates, and commonly leads to the euthanasia of affected dogs. In cats, tracheobronchitis, conjunctivitis, and pneumonia have been associated with Bordetella bronchiseptica infection-but most cases of upper-respiratory infection (URI) probably are caused by herpesvirus and calicivirus, and many B. bronchiseptica culture-positive cats are clinically normal. Our prospective observational study was undertaken to document the contribution of B. bronchiseptica to disease in cats and dogs from two animal shelters undergoing outbreaks of canine kennel cough, to evaluate whether cross-species transmission might have occurred, and to determine if the presence of infected cats represented a risk to dogs. Clinically defined cases of kennel cough in dogs and URI in cats were investigated in two shelters by calculating clinical-disease incidence, alveolar-lavage cytological examination, bacterial and viral cultures, antibiotic-susceptibility testing, and molecular fingerprinting by pulsed-field gel electrophoresis.In a 40-cat and 40-dog "no-kill" shelter, the prevalences of culture positivity were 47% for B. bronchiseptica and 36% for calicivirus at the same time as two resident dogs demonstrated clinical cough. When no dogs had kennel cough 3 months later, 10% of cats were B. bronchiseptica-culture-positive and 63% calicivirus positive. In a large traditional shelter, the incidence of kennel cough in dogs increased over 12 weeks to a maximum of 19 cases/week/120 dogs, during which time the culture prevalence was 23% for B. bronchiseptica in dogs and 47% in cats. Three to 6 months before the kennel-cough epidemic, no dogs or cats were B. bronchiseptica positive. Very little genetic variability was detected in isolates from these shelters; all isolates except one corresponded to a single strain type which was identical to the pattern in a vaccine used in these shelters. Isolates from other cats, a horse, a llama, and a sea otter were genetically distinct from the shelter isolates. There was widespread resistance to cephalosporins and ampicillin, but low or no resistance to amoxicillin/clavulanate, trimethoprim-sulfamethoxazole, tetracycline, and enrofloxacin. Greater percent resistance was observed in the traditional shelter than in the no-kill shelter and feline isolates were more likely to be resistant than canine isolates. 相似文献
6.
Studies on the predatory insects of the Sycamore lace bug (Corythuca ciliata (Say))
In our previous work (Maceljski, andBalarin, 1974) we presented some results of our first investigations of the new insect introduced in Europe from North America, the Sycamore lace bug (Corythuca ciliata [SAY]). There we concluded that it is necessary to bring this insect under control especially by biological means.In our recent work we established that some most usual predatory bugs in Yugoslavia, i. e.Nabis pseudoferus Rm.,Rhinocoris iracundus iracundus (Pd.) andHimacerus mirmicoides (O. C.) are in the laboratory very effective sucking on the Sycamore lace bugs. Therefore it is possible that these predators will have a negative influence on the population-dynamic of this new nuisible insects in Europe. The investigation added to the knowledge of the possible preys of these bugs too.
Die Untersuchungen wurden von der Stadt Zagreb unterstutzt. 相似文献
Die Untersuchungen wurden von der Stadt Zagreb unterstutzt. 相似文献
7.
In vivo, resumption of oocyte meiosis occurs in large ovarian follicles after the
preovulatory surge of luteinizing hormone (LH). The LH surge leads to the activation of a broad signaling
network in mural granulosa cells equipped with LH receptors. The signals generated in the mural granulosa
cells are further augmented by locally produced peptides or steroids and transferred to the cumulus cell
compartment and the oocyte itself. Over the last decade, essential progress has been made in the
identification of molecular events associated with the final maturation and ovulation of mammalian oocytes.
All new evidence argues for a multiple roles of mitogen-activated protein kinase 3/1 (MAPK3/1) in the
gonadotropin-induced ovulation processes. However, the knowledge of gonadotropin-induced signaling pathways
leading to MAPK3/1 activation in follicular cells seems limited. To date, only the LH-induced transactivation
of the epidermal growth factor receptor/MAPK3/1 pathway has been described in granulosa/cumulus cells even
though other mechanisms of MAPK3/1 activation have been detected in other types of cells. In this review, we
aimed to summarize recent advances in the elucidation of gonadotropin-induced mechanisms leading to the
activation of MAPK3/1 in preovulatory follicles and cultured cumulus-oocyte complexes and to point out a
specific role of this kinase in the processes accompanying final maturation of the mammalian oocyte. 相似文献
8.
Claudia Böhm Manuela Schnyder Stig Milan Thamsborg Caryn M. Thompson Candace Trout Sonja Wolken Beate Schnitzler 《Veterinary parasitology》2014,199(3-4):272-277
Angiostrongylus vasorum is an increasingly reported parasite in Europe that develops in dogs after ingestion of infective third stage larvae (L3) that reside in gastropod molluscs which are needed to complete the parasite's life-cycle. Infection can produce a diversity of clinical signs, determined by involvement of the respiratory, neurological, and/or coagulation system, with a likely fatal outcome in the absence of treatment. Few drugs have been shown to reliably prevent infection, and data on treatment of infections is limited. A controlled, randomized, partially blinded laboratory study was therefore executed to evaluate the efficacy and safety of a combination tablet of spinosad/milbemycin oxime in dogs inoculated with approximately 250 A. vasorum L3. Sixteen healthy nematode free adult dogs were randomly allocated to two study groups of 8 dogs each. Thirty days post inoculation (dpi) all dogs in the fed state were treated: dogs in group B were treated with spinosad and milbemycin oxime at the dose rates of 45–60 mg/kg and 0.75–1.0 mg/kg bodyweight, respectively, approximately the lower half portion of the expected full unit dose range; dogs in group A were treated with placebo tablets. All dogs were euthanized and necropsied 56–58 dpi. The heart and lungs were examined to determine the presence of A. vasorum. All placebo group dogs were infected at necropsy with counts ranging from 22 to 98 adult worms and a geometric mean worm count of 55.2. In contrast, the geometric mean worm count in the spinosad/milbemycin oxime group was 0.7 with worm numbers ranging from 0 to 8. The results of this study demonstrate that a single treatment with the tablet combination of spinosad and milbemycin oxime administered 30 dpi provided 98.8% preventive efficacy against development of adult A. vasorum infections. Monthly treatments with spinosad and milbemycin oxime have the potential to prevent the establishment of infections with A. vasorum in dogs. 相似文献
9.
禽用谷物品质的预测和改善 总被引:1,自引:0,他引:1
Milan Hruby Andrew Harker 《饲料广角》2001,(21):38-39,19
小麦、大麦和黑小麦等谷物在营养价值方面(例如代谢能)的变化已被业界人士广为了解,这种营养价值的变异造成了肉鸡料肉比不可预测及在某些情况下能产生粘湿的粪便.现已充分认识到,上述谷物中所含的可溶性长链阿拉伯木聚糖和β-葡聚糖是引起肠道食糜高粘性等问题的主要原因.非淀粉多糖酶,如木聚糖酶和β-葡聚糖酶,能通过部分的破坏上述物质的纤维结构从而有效地减少肠内的粘性.这种作用的衍生效应是成倍的,而最终结果是增加了养分的利用率.自80年代末期开始,使用小麦、大麦和黑小麦作为饲料能源谷物的国家便已经商业化地使用非淀粉多糖酶来提高养殖的经济效益,而最近研发的小麦品质快速测定法(芬兰饲料国际公司的AvicheckTM 应用软件)能使饲料厂根据小麦的品质和用量来优化酶制剂的最佳添加量,从而达到最大的利润. 相似文献
10.
Dragan Nonic John C. Bliss Vojislav Milijic Nenad Petrovic Mersudin Avdibegovic Milan Mataruga 《Small-Scale Forestry》2011,10(4):435-455
Small-scale forestry in Serbia is characterized by high fragmentation of properties, a large number of parcels and forest
owners. Numerous activities for private forest owners in Serbia supported by the State, FAO and CEPF have resulted in an increased
interest of owners in forming private forest owners’ associations (PFOA). The goal of this paper is to explore preconditions
that are necessary for organizing private forest owners in Serbia into effective associations. In order to reach this goal,
results of PRIFORT project were used. The over-arching research questions of this paper are: “What is the level of interest
among forest owners in forming owners’ associations?”; “Why has forest owner interest in organizing developed so slowly?”
and “What are the necessary preconditions for the development of private forest owners’ organizations in the country?” In
order to answer these questions, quantitative survey with 42 close, open and Likert scale questions was conducted. Sample
size was determined following Malhotra’s proportion method and, in total, 350 private forest owners, from nine municipalities
were interviewed. Results of this paper show that majority of respondents are very little or not at all aware of existing
legislation. Almost half of respondents consider that their interests are not represented well. Although about 50% of interviewed
forest owners miss interest organization, only 0,3% are members of PFOA. More than 70% are ready to join association, if it
would provide some economic advantages. 相似文献