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1.
ObjectiveTo compare the haemodynamic effects of three premedicant regimens during propofol-induced isoflurane anaesthesia.Study designProspective, randomized cross-over study.AnimalsEight healthy purpose-bred beagles aged 4 years and weighing mean 13.6 ± SD 1.9 kg.MethodsThe dogs were instrumented whilst under isoflurane anaesthesia prior to each experiment, then allowed to recover for 60 minutes. Each dog was treated with three different premedications given intravenously (IV): medetomidine 10 μg kg?1 (MED), medetomidine 10 μg kg?1 with MK-467 250 μg kg?1 (MMK), or acepromazine 0.01 mg kg?1 with butorphanol 0.3 mg kg?1 (AB). Anaesthesia was induced 20 minutes later with propofol and maintained with isoflurane in oxygen for 60 minutes. Heart rate (HR), cardiac output, arterial blood pressures (ABP), central venous pressure (CVP), respiratory rate, inspired oxygen fraction, rectal temperature (RT) and bispectral index (BIS) were measured and arterial and venous blood gases analyzed. Cardiac index (CI), systemic vascular resistance index (SVRI), oxygen delivery index (DO2I), systemic oxygen consumption index (VO2I) and oxygen extraction (EO2) were calculated. Times to extubation, righting, sternal recumbency and walking were recorded. The differences between treatment groups were evaluated with repeated measures analysis of covariance.ResultsHR, CI, DO2I and BIS were significantly lower with MED than with MMK. ABP, CVP, SVRI, EO2, RT and arterial lactate were significantly higher with MED than with MMK and AB. HR and ABP were significantly higher with MMK than with AB. However, CVP, CI, SVRI, DO2I, VO2I, EO2, T, BIS and blood lactate did not differ significantly between MMK and AB. The times to extubation, righting, sternal recumbency and walking were significantly shorter with MMK than with MED and AB.Conclusions and clinical relevanceMK-467 attenuates certain cardiovascular effects of medetomidine in dogs anaesthetized with isoflurane. The cardiovascular effects of MMK are very similar to those of AB.  相似文献   
2.
Cage fish farming in natural and artificial lakes has become increasingly popular in recent years in tropical countries. The most commonly farmed tropical fish species is the Nile tilapia (Oreochromis niloticus L.). The aim of this study was to characterize the concentration of phosphorus, total ammonia nitrogen and chlorophyll a from existing fish farms (FF) in Lake Palminhas, located in Linhares/ES, Brazil. Three transects were drawn from 0 to 500 m from each of the four FF (FF1 to FF4) in the lake during six trials (three in the rainy season and three in the dry season). The lake presented a monomictic‐hot pattern, with stratification during the rainy season. Dilution of the monitored parameters did not occur sufficient over a distance of up to 500 m from the FF. The location of the FF in the lake and the input of N and P were critical to ensure optimal mixing conditions because the worst results was observed for the fish farm (FF1) located on a finger of the lake, where the highest concentrations of total phosphorus and chlorophyll a occurred. It was also noted that there was possible total phosphorus interference between FF3 and FF4. The results of this study demonstrate that Lake Palminhas had a low dilution power, and these findings may inform environmental assessments of cage fish farming in this region, providing instruments that may support environmental control of cage fish farming.  相似文献   
3.
Evaluations on community forestry outcomes are important to observe whether the program community forestry produces what it has promised. For the evaluation -as an alternative to the comprehensive criteria and indicators on sustainable community forestry-, we propose an approach based on the core policy objectives of the program. In fact, community forestry is very much connected to the following three objectives of: 1) alleviating the poverty of forest users, 2) empowering them, and 3) improving the condition of the forests. Based on field tests in two community forests in Indonesia, the focus on the core policy objectives appears to provide a more practical approach than the use of complex criteria and indicators. We conclude that our approach allows rapid evaluations and eventually reduces the associated costs and time without compromising the goals of the evaluation.  相似文献   
4.
ObjectiveTo compare the cardiopulmonary effects of intravenous (IV) and intramuscular (IM) medetomidine and butorphanol with or without MK-467.Study designProspective, randomized experimental cross-over.AnimalsEight purpose–bred beagles (two females, six males), 3–4 years old and weighing 14.5 ±1.6 kg (mean ± SD).MethodsAll dogs received four different treatments as follows: medetomidine 20 μg kg?1 and butorphanol tartrate 0.1 mg kg?1 IV and IM (MB), and MB combined with MK-467,500 μg kg?1 (MBMK) IV and IM. Heart rate (HR), arterial blood pressures (SAP, MAP, DAP), central venous pressure (CVP), cardiac output, respiratory rate (fR), rectal temperature (RT) were measured and arterial blood samples were obtained for gas analysis at baseline and at 3, 10, 20, 30, 45 and 60 minutes after drug administration. The cardiac index (CI), systemic vascular resistance index (SVRI) and oxygen delivery index (DO2I) were calculated. After the follow-up period atipamezole 50 μg kg?1 IM was given to reverse sedation.ResultsHR, CI and DO2I were significantly higher with MBMK after both IV and IM administration. Similarly, SAP, MAP, DAP, CVP, SVRI and RT were significantly lower after MBMK than with MB. There were no differences in fR between treatments, but arterial partial pressure of oxygen decreased transiently after all treatments. Recoveries were uneventful following atipamezole administration after all treatments.Conclusions and clinical relevanceMK-467 attenuated the cardiovascular effects of a medetomidine-butorphanol combination after IV and IM administration.  相似文献   
5.
Background  Petroleum products are widely used in various sections of industry and they are one of the most abundant sources of environmental contamination. These products are classified by their physico-chemical properties such as boiling point, density and viscosity. Oil contamination in the environment is primarily evaluated by measuring the chemical concentrations of petroleum products in the solid or water phase. The results of chemical analyses do not correspond directly with the harmful environmental effects of petroleum products on the soil flora and fauna, because the interactions between oil compounds and the production of their methabolites in soil are not measured in chemical assessments. These kinds of effects of complex chemical mixtures in soil can be estimated by bioassays. Therefore, ecotoxicological tests are important for estimating soil quality in the risk assessment of oil-contaminated soil sites. Objectives  The objective of this study was to examine the oil-contaminated soil site of a closed petrol station with both chemical and ecotoxicological methods. The goals of this study were to compare the sensitivity of the terrestrial and aquatic bioassays and to compare the toxicity responses of aquatic bioassays determined from three different extraction procedures. In addition, our aim was to characterise a cost-effective battery of bioassays that could be applied to a comparison of oil-contaminated soils. It was in our interest to investigate oil-contaminated soil with oil concentrations of 2500–12000 mg/kg and to find out the possible differences between terrestrial and aquatic toxicity tests. Methods  Six soil samples from a closed petrol station were examined for toxicity with terrestrial and aquatic tests. Terrestrial tests includedEnchytraeus albidus survival and reproduction assays and seed germination assays using wheat, cress, lettuce, and red clover seeds and growth inhibition assays of onions. The toxicities of the water-extractable fractions of the soil samples obtained from three different extractions were tested with aquatic bioassays based on plants (onion and duckweed growth inhibition tests), microbes (luminescent bacteria test), and enzyme inhibition (reverse electron transport test, RET). Chemical analyses of the solid samples were carried out simultaneously. Results. Oil concentrations ranged from 2500 to 12000 mg/kg, BTEX varied from 300 to 2800 mg/kg, and fuel additives: MTBE and TAME from 0.0 1 to 260 mg/kg. Only the sample contain-ing 12000 mg/kg oil had a significant toxic impact on all test organisms. Soil samples with oil concentrations 2500–6200 mg/ kg had no or only slight adverse effects on the test organisms with one exception, theE. albidus reproduction test. TheE. albidus survival and reproduction tests were the most sensitive bioassays of the terrestrial tests, and the luminescent bacteria test of the aquatic tests.  相似文献   
6.
The Tanzanian Community-Based Forest Management policy is based on the assumption that formalized forest tenure by village communities results in increased incentives for sustainable forest management. We compared the policy expectations to village forest management practices in northeastern Tanzania. Findings suggest that the practices follow policy in terms of increased security of rights, but exclusionary management of village forests precludes livelihood benefits while costs are unevenly distributed. Management appears effective at the village scale, but concerted efforts are likely to be needed to increase its long-term and landscape-level sustainability, and to create more significant incentives for the communities involved.  相似文献   
7.
ObjectiveTo record, with a thermal camera, peripheral temperature changes during different sedation protocols and to relate the results to changes in the rectal temperature.Study designRandomized crossover part-blinded experimental study.AnimalsEight healthy purpose-bred neutered Beagles (two females and six males) weight 14.5 ± 1.6 kg (mean ± SD) and aged 3–4 years.MethodsEach dog was sedated four times. Treatments were medetomidine 20 μg kg?1 and butorphanol 0.1 mg kg?1 (MB) with or without MK-467 500 μg kg?1 (MK). Both drug combinations were administered IV and IM as separate treatments. A thermal camera (T425, FLIR) with a resolution of 320 by 240 was used for imaging.The dogs were placed in lateral recumbency on an insulated mattress. Digital (DFT) and metatarsal footpad temperatures (MFT) were measured with thermography. Thermograms and rectal temperature (RT) were taken before and at 3, 10, 20, 30, 45 and 60 minutes after treatment.ResultsAt 60 minutes after drug administration, MFT was higher (p < 0.001) after MB+MK (34.5 ± 1.1 IV, 34.8 ± 0.5 IM) than MB (31.1 ± 2.9 IV, 30.5 ± 3.6 IM), DFT was higher (p < 0.001) after MB+MK (33.6 ± 1.4 IV, 34.0 ± 0.6 IM) than MB (26.7 ± 1.4 IV, 26.7 ± 2.5 IM), and RT was lower (p < 0.001) after MB+MK (36.7 ± 0.8 IV, 36.9 ± 0.3 IM) than MB (37.5 ± 0.3 IV, 37.4 ± 0.4 IM), with both routes. The change from baseline was greater with MB+MK than MB in all variables.ConclusionsSuperficial temperature changes can be seen and detected with thermography. MK-467 used with MB resulted in increased superficial temperatures and a decline in rectal temperature compared to MB alone.Clinical relevanceThe sedation protocol may influence core temperature loss, and may also have an effect on thermographic images.  相似文献   
8.
The information on biogeochemistry of silver (Ag) is scarce and mechanisms of Ag uptake by plants are still unclear. We studied the impact of silver sulfate (Ag2SO4) and silver nitrate (AgNO3) on biomass of wheat seedlings, the rhizosphere proteins and uptake of nutrients and trace elements. Most part of Ag was accumulated in roots. Concentrations of Ag in leaves remained the same as in control plants. Both treatments (Ag2SO4 and AgNO3) affected biomass of the seedlings. Plant biomass was decreased more after treatment with AgNO3. Both Ag2SO4 and AgNO3 reduced leaf concentrations of sodium and barium and root concentrations of calcium. Over time (three days), protein concentration in the rhizosphere of control plants and plants treated with AgNO3 increased, whereas treatment with Ag2SO4 reduced concentration of the rhizosphere proteins. In soil treated with Ag2SO4 only low-molecular-weight proteins were found. In the control soil and in soil treated with AgNO3 we also observed polydisperse fraction.  相似文献   
9.
ObjectiveTo study the effects of oromucosal detomidine gel administered sublingually to calves prior to disbudding, and to compare its efficacy with intravenously (IV) administered detomidine.Study designRandomised, prospective clinical study.AnimalsTwenty dairy calves aged 12.4 ± 4.4days (mean ± SD), weight 50.5 ± 9.0 kg.MethodsDetomidine at 80 μg kg?1 was administered to ten calves sublingually (GEL) and at 30 μg kg?1 to ten control calves IV (V. jugularis). Meloxicam (0.5 mg kg?1) and local anaesthetic (lidocaine 3 mg kg?1) were administered before heat cauterization of horn buds. Heart rate (HR), body temperature and clinical sedation were monitored over 240 minutes. Blood was collected from the V. cephalica during the same period for drug concentration analysis. Pharmacokinetic variables were calculated from the plasma detomidine concentration-time data using non-compartmental methods. Statistical analyses compared routes of administration by Student’s t-test and linear mixed models as relevant.ResultsThe maximum plasma detomidine concentration after GEL was 2.1 ± 1.2 ng mL?1 (mean ±SD) and the time of maximum concentration was 66.0 ± 36.9 minutes. The bioavailability of detomidine was approximately 34% with GEL. Similar sedation scores were reached in both groups after administration of detomidine, but maximal sedation was reached earlier in the IV group (10 minutes) than in the GEL group (40 minutes). HR was lower after IV than GEL from 5 to 10 minutes after administration. All animals were adequately sedated, and we were able to administer local anaesthetic without resistance to all of the calves before disbudding.Conclusions and clinical relevanceOromucosally administered detomidine is an effective sedative agent for calves prior to disbudding.  相似文献   
10.
Eucalyptus is very recalcitrant to in vitro culture. In this research, an efficient shoot organogenesis system was developed using 60-day-old plants of Eucalyptus globulus grown in vitro and non-aerated liquid medium to improve shoot proliferation. Cultures were initiated with hypocotyls and leaf segments from plantlets cultivated on semisolid ½ MS modified medium supplemented with 4.44 µM 6-Benzyladenine (BA) and 16.1 µM 1-Naphthaleneacetic acid (NAA). Calli were transferred to shoot induction medium, with either 0.5 or 2.7 µM NAA. Shoot multiplication was carried out on 4.44 µM BA + 0.5 µM NAA medium, and semisolid and non-aerated liquid systems were compared for improving shoot proliferation. Rooting of adventitious shoots was evaluated on medium containing NAA or Indole-3-butyric acid -IBA (5 and 16 µM). Callogenesis was obtained from both types of explants, although shoot formation was only obtained from leaf-derived calli. Shoot proliferation on 4.44 µM BA + 0.5 µM NAA resulted in the most shoots/callus. Non-aerated liquid medium was more efficient in promoting shoot multiplication (53.5 shoots/callus) than was semisolid medium (28.5 shoots/callus). Levels of phenolic compounds were significantly reduced in the shoots cultivated in liquid medium. Efficient rooting (76%) was obtained using 16 µM IBA.  相似文献   
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