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81.
Two major quantitative trait loci (QTLs) associated with resistance to powdery mildew (Blumeria graminis f. sp. hordei) were previously identified on chromosome 7H of the Spanish barley line SBCC097. The two QTLs seemed to share the same chromosomal position as the major genes mlt and Mlf, which were formerly described in Hordeum vulgare ssp. spontaneum-derived lines. In the present work, different lines that carry mlt (RS42-6*O), Mlf (RS137-28*E), or a combination of both (SI-4 and SI-6) were compared with SBCC097 to evaluate their relatedness at the phenotypic, cellular, and genetic levels. The resistance of the lines was characterised by inoculating them with a set of 27 isolates of B. graminis, which displayed a wide range of virulence. It was revealed that SBCC097 possessed a distinctive resistance spectrum. Microscopic assessment of the cytological development of the resistance response showed that SBCC097 clearly formed fewer well-established colonies and secondary hyphae than the other lines. This was confirmed by the infection type recorded after visual inspection. Genetic analyses of all five lines, based on markers flanking the QTLs derived from SBCC097, supported the macroscopic and microscopic data and pointed to the presence of a combination of novel genes or alleles in SBCC097, which may be included in the category of “intermediate-acting” genes, governing resistance mainly at the post-penetration stage.  相似文献   
82.
Arctostaphylos uva-ursi plant associations have long been suggested to be a suitable location for afforestations, but systematic studies on the observed beneficial effect are still missing in Alpine areas. In this study we address the question which ectomycorrhizal (ECM) fungal communities exist in Austrian alpine and subalpine Arctostaphylos habitats, and if they persist in A. uva-ursi stands even hundred of years after disappearance of trees in these areas. The diversity of fungal communities associated with A. uva-ursi was assessed in four study sites (1800–2450 m a.s.l.) in the Central European Alps of Tyrol (Austria). Three approaches were applied: (i) collecting and identifying fungal fruit bodies; (ii) studying the arbutoid mycorrhiza morphotypes of A. uva-ursi; (iii) molecular identification of the most common arbutoid morphotypes. The detected diversity of ECM fungal species was very high (99 taxa), and the occurrence of e.g. Boletus, Cantharellus, Suillus, Tricholoma, Russula spp. in sites that have been treeless for centuries is especially remarkable. Fruit bodies of 82 fungal species were found in association with A. uva-ursi, 63 of them were ECM. Seventy arbutoid morphotypes were detected on 2072 mycorrhized root tips, and 39 taxa of basidiomycete mycobionts were identified with molecular methods. Twelve Cortinarius spp. clearly dominated the mycobiont species richness, followed by nine spp. of Thelephoraceae and four spp. of Boletaceae. Most mycobionts of A. uva-ursi were generalists, but fungal taxa (e.g. Lactarius deterrimus and Suillus spp.) known to be specifically associated with other host plants were also detected. We therefore consider A. uva-ursi as a “non-selective” host, providing mycorrhizal inoculum of highly specialized and effective mycorrhizal fungi for afforestation. This explains why A. uva-ursi plant associations represent suitable locations for forest regeneration and afforestation, especially in the harsh environmental conditions of subalpine and alpine sites.  相似文献   
83.
RATIONALE FOR THE STUDY: A review of abstracts presented at nine annual meetings of the American College of Veterinary Anesthesiologists was undertaken to determine the average time to publication and the differences found between conference abstracts and final publications. Concerns about and advantages of using such abstracts in our teaching are considered. METHODOLOGY: Conference proceedings during the years 1990 through 1999 were considered. Key word and author searches using two common search engines were carried out to find whether abstracts presented had been published. The original article or its abstract was reviewed for consistency with the conference abstract. RESULTS: Of 283 abstracts examined, 73.5% were published in journals as full articles. The overall delay (+/-SD) in publication was 24.3 +/- 21.0 months. Common reasons for not publishing included too little time, more interest in carrying out the work than in writing it up, and other more demanding tasks. Authors indicated the intention of completing a submission on approximately 10% of the unpublished abstracts. The final articles reviewed showed major differences in key aspects from the abstract presented in 7% of the cases. In half of these cases, clinical action could have been affected by a change in emphasis of the conclusions. CONCLUSIONS: Because of the delay in publication of research, peer review of standardized abstracts should be encouraged. This material can be used to introduce students to new drugs, techniques, and results that may not otherwise become available until after their graduation. However, caution must be exercised in using this information, both because significant differences were noted in final publications and because unpublished research may be poorly interpreted at the time of presentation. This study emphasizes the value of critical review and lifelong learning in our careers.  相似文献   
84.
Spontaneous ventilation during positive pressure ventilation was observed in a 4-year-old DSH cat maintained under general anesthesia with isoflurane delivered with a nonrebreathing system. This was accompanied by an increase in heart rate and blood pressure. On investigation, neither an inadequate plane of anesthesia, nor hypoxemia, nor hyperthermia was present. The nonrebreathing system was replaced and the hypercapnia resolved. A defect in the inner fresh gas delivery tube of the Bain system was identified. A simple and quick test is described which can be performed to verify the integrity of the inner tube of the Bain breathing circuit.  相似文献   
85.
The purpose of this study was to assess the use of surface area derived tidal volume in anesthetized ventilated dogs (n = 71, random assignment) compared to settings by experienced personnel. There was no significant difference (P = 0.1030) between methods (p(a)CO(2) of 43.1 ± 7 mmHg and 39.8 ± 7 mmHg, respectively). Surface area derived tidal volume can achieve satisfactory ventilation.  相似文献   
86.
OBJECTIVE: To determine minimum alveolar concentration (MAC) of isoflurane in green iguanas and effects of butorphanol on MAC. DESIGN: Prospective randomized trial. ANIMALS: 10 healthy mature iguanas. PROCEDURE: in each iguana, MAC was measured 3 times: twice after induction of anesthesia with isoflurane and once after induction of anesthesia with isoflurane and IM administration of butorphanol (1 mg/kg [0.45 mg/lb]). A blood sample was collected from the tail vein for blood-gas analysis at the beginning and end of the anesthetic period. The MAC was determined with a standard bracketing technique; an electrical current was used as the supramaximal stimulus. Animals were artificially ventilated with a ventilator set to deliver a tidal volume of 30 mL/kg (14 mL/lb) at a rate of 4 breaths/min. RESULTS: Mean +/- SD MAC values during the 3 trials (2 without and 1 with butorphanol) were 2.0 +/- 0.6, 2.1 +/- 0.6, and 1.7 +/- 0.7%, respectively, which were not significantly different from each other. Heart rate and end-tidal partial pressure of CO2 were also not significantly different among the 3 trials. Mean +/- SD heart rate was 48 +/- 10 beats/min; mean end-tidal partial pressure of CO2 was 22 +/- 10 mm Hg.There were no significant differences in blood-gas values for samples obtained at the beginning versus the end of the anesthetic period. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the MAC of isoflurane in green iguanas is 2.1% and that butorphanol does not have any significant isoflurane-sparing effects.  相似文献   
87.
ObjectiveTo evaluate and compare the cardiopulmonary effects of induction of anesthesia with isoflurane (Iso), ketamine–diazepam (KD), or propofol–diazepam (PD) in hypovolemic dogs.Study designProspective randomized cross–over trial.AnimalsSix healthy intact, mixed breed, female dogs weighing 20.7 ± 4.2 kg and aged 22 ± 2 months.MethodsDogs had 30 mL kg?1 of blood removed at a rate of 1.5 mL kg?1 minute?1 under isoflurane anesthesia. Following a 30–minute recovery period, anesthesia was reinduced. Dogs were assigned to one of three treatments: isoflurane via facemask using 0.5% incremental increases in the delivered concentration every 30 seconds, 1.25 mg kg?1 ketamine and 0.0625 mg kg?1 diazepam intravenously (IV) with doses repeated every 30 seconds as required, and 2 mg kg?1 propofol and 0.2 mg kg?1 diazepam IV followed by 1 mg kg?1 propofol increments IV every 30 seconds as required. Following endotracheal intubation all dogs received 1.7% end–tidal isoflurane in oxygen. Cardiopulmonary variables were recorded at baseline (before induction) and at 5 or 10 minute intervals following endotracheal intubation.ResultsInduction time was longer in Iso (4.98 ± 0.47 minutes) compared to KD (3.10 ± 0.47 minutes) or PD (3.22 ± 0.45 minutes). To produce anesthesia, KD received 4.9 ± 2.3 mg kg?1 ketamine and 0.24 ± 0.1 mg kg?1 diazepam, while PD received 2.2 ± 0.4 mg kg?1 propofol and 0.2 mg kg?1 diazepam. End–tidal isoflurane concentration immediately following intubation was 1.7 ± 0.4% in Iso. Arterial blood pressure and heart rate were significantly higher in KD and PD compared to Iso and in KD compared to PD. Arterial carbon dioxide partial pressure was significantly higher in PD compared to KD and Iso immediately after induction.Conclusions and clinical relevanceIn hypovolemic dogs, KD or PD, as used in this study to induce anesthesia, resulted in less hemodynamic depression compared to isoflurane.  相似文献   
88.
Spatial distribution maps depicting the concentrations of antimony, lead, tin, copper and zinc, and the presence of land-use units were generated for Mühlburg, a district of the City of Karlsruhe, Germany. The influence of the spatial land-use structure on the distributions of the element concentrations is statistically evaluated and discussed. The variography for Mühlburg shows an average range of 200-400 m for the spatial correlations of Sb, Pb, Sn and Zn. The variograms of Pb and Zn are characterised by hole effects at 300 m distances, i.e. the result of repeated stronger spatial correlations for certain distances between the sample sites. Most probably, this is an effect of the typical urban structure of streets, buildings, green spaces, and industry. Kriging method was used for the interpolation of Sb, Pb, Sn and Zn concentrations. Only Cu does not show a spatial correlation. In this case, the interpolation was carried out with a smoothed triangulation routine. Pollution plumes of point sources such as lead works, a bell foundry and a coal-fired thermal power station superimpose the more diffuse pollution from traffic, household heating processes, waste material disposal, etc. The trace element concentrations in soils of housing areas increase with the age of the developed area. Industrial areas show the highest level of pollution, followed by housing areas developed before 1920, traffic areas, allotments, housing areas developed between 1920 and 1980, parks and sports areas, cemetery and housing areas developed after 1980. It is demonstrated that spatial distribution maps of element concentrations indicate potential emission sources of harmful substances, even if the emission itself or the direct surrounding soil have not been analysed. The analytical tools presented enable town planners to discern areas of higher soil pollution. Detailed investigations can be focussed on these areas to evaluate the possibilities of soil usage and transfer. These methods enable one to manage urban soil in an adequate manner. For these reasons, the methods demonstrated support an urban environmental impact assessment and are a part of a sustainable urban soil management.  相似文献   
89.
Environmental factors are known to modify the life history of marine ectotherms. In a 16‐month laboratory experiment, we investigated the influence of temperature and presence of predators on life‐history parameters including shell growth, survival and the energy investment in reproduction and body mass of the short‐lived (2–3 years) scallop Argopecten ventricosus. In parallel, A. ventricosus was maintained in the field at the Pacific coast of Baja California, México, to compare growth, survival and reproductive effort under natural conditions. For the laboratory treatments, scallops were reared at simulated field temperatures (SFT), 5 °C above SFT and in the presence of predators. Elevated water temperatures caused higher growth and gonad production, although at the cost of increased mortality. Presence of predators induced energy allocation to muscle rather than gonad growth, deferred spawning and extended survival. Field scallops exhibited higher growth, higher reproductive investment and were able to reproduce twice, whereas all laboratory scallops died after the first spawning. The natural variability of environmental parameters such as food and temperature may thus support optimal growth in the field, and when animals are protected from predators, reproduction in the second year of life.  相似文献   
90.
By means of surveys in 48 salmon farms in Chile, and the analysis of fish mortality in 23, the results showed that attacks by the South American sea lion, Otaria flavescens, were periodical at a daily and seasonal scale, and because of their natural nocturnal feeding behaviour, were more frequent at night and in fall–winter seasons. The attacks varied markedly between the farms studied. No relation was found between the intensity of attacks, the distance to the nearest colony of sea lions and the population in the colony. Differences found between farms could be because of the different protective devices used, namely anti‐predator nets, acoustic harassment devices (AHDs) and fibreglass models of killer whales, and the way in which they were used. Of these devices, only the anti‐predator net achieved a permanent reduction in sea lion attacks. Both AHDs and fibreglass killer whales were inefficient in the short term.  相似文献   
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