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61.
62.
Improving our understanding about how natural enemies respond to semi-natural habitats and crop management scattered in the landscape may contribute to the development of ecologically based pest management strategies maximising biological control services. We investigated how soil tillage and semi-natural habitats influenced the parasitism rates of pollen beetle (Meligethes aeneus F.) larvae at 8 different spatial scales (from 250 to 2000 m radius circular sectors) in 42 oilseed rape (OSR) fields. We used multimodel inference approaches to identify and rank the influence of soil tillage and semi-natural habitats on parasitism rates, and to quantify the importance of each scale. Parasitism rates were due to three univoltine parasitoid species (Tersilochus heterocerus, Phradis morionellus and P. interstitialis) and varied from 0 to 98%. We found that both fine and large scales contributed to explain significantly parasitism rates, indicating that biological control of pollen beetle is a multi-scale process. At the 250 m scale, parasitism rates of T. heterocerus were positively related to the proportion of semi-natural habitats and the proximity to previous year OSR fields. At large scales (1500 to 2000 m), parasitism rates of T. heterocerus were positively related to semi-natural habitats and negatively related to the proportion of previous year OSR fields with conventional soil tillage. Parasitism rates of Phradis spp. were only positively related to the proportion of semi-natural habitats at the 1250 and 1500 m scales. These multi-scale effects are discussed in relation to the influence of semi-natural habitats and soil tillage on parasitoid populations and their movement behaviours within the landscape.  相似文献   
63.
Recent technological advances in 3D printing have resulted in increased use of this technology in human medicine, and decreasing cost is making it more affordable for veterinary use. Rapid prototyping is at its early stage in veterinary medicine but clinical, educational, and experimental possibilities exist. Techniques and applications, both current and future, are explored and illustrated in this article.  相似文献   
64.
Hydromorphone (HY) has not been objectively assessed as an analgesic in cats. It has been suggested that butorphanol (B) can have a synergistic action with pure μ‐agonists. The aim of this study was to assess the antinociceptive activity of a single dose of HY, and to examine the effect of concurrent B administration on the thermal threshold (TT). Thermal thresholds were measured following IM administration of HY, B, a combination of B and HY (HY‐B), or saline (S). Six cats (four spayed females, two castrated males, 4.75–6.8 kg) were used. Each cat received HY (0.1 mg kg?1), B (0.4 mg kg?1), HY (0.1 mg kg?1), and B (0.4 mg kg?1) (HY‐B), or S (0.05 mL kg?1) in a randomized, blinded, cross‐over study design. Each cat received each treatment, with at least 12 days interval between the treatments. All injections were IM randomized to left or right quadriceps using a 24 SWG needle. Twenty‐four hours prior to each study, the thorax of each of the cats was shaved. On the day of the study, TT was measured using a thorax‐mounted thermal threshold‐testing device specifically developed for cats. Skin temperature was recorded before each test and then the heater was activated. When the cat responded by flinching, turning, or jumping, the stimulus was terminated and the threshold temperature was recorded. Three baseline thresholds were recorded over 1 hour before IM injection of test drug. Thermal threshold cut‐off was 55.5 °C. TT was measured at 5 and 15 minutes, every 15 to 360 minutes, every 30 minutes to 8 hours, every hour to 12 hours, and at 24 hours post‐injection. Threshold data were analyzed using an anova with a repeat factor of time. Behavioral adverse effects (dysphoria) were associated with B administration, but not with HY or HY‐B administration (these produced calm euphoria). The control group was stable over time (p = 0.22) (mean threshold 40.15 °C). Overall, there was no period effect, no significant effect of administering B, but a significant effect (raised TT) of administering HY or HY‐B. If the mean value of one of the experimental groups differed from the control group (40.075 °C) by more than 2.355 °C (>42.425 °C), that mean was significantly different from control at p < 0.05 (Bonferroni's t‐tests). This occurred between 15 and 165 minutes for B, from 15 to 345 minutes for HY, and between 15 and 540 minutes for HY‐B. In this model, HY provided up to 5.75 hours of antinociception at 0.1 mg kg?1, and concurrent administration of butorphanol (0.4 mg kg?1) decreased the intensity of antinociception over the first 2 hours, but extended the duration of significant antinociception to about 9 hours.  相似文献   
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66.
From a nutritional point of view, cereal lipids include valuable molecules, such as essential fatty acids, phytosterols, and fat-soluble vitamins. Spelt (Triticum spelta L.) is an alternative hulled bread cereal mostly grown in Belgium, where it is mainly intended for animal feed but should increasingly be used for human consumption. The present research focused on phytosterol quantification by LC/APCI-MS2 in saponified wholemeal extracts of 16 dehulled spelt and 5 winter wheat (Triticum aestivum L.) varieties grown in Belgium during 2001-2002 at the same location. Glycosylated sterols and free and formerly esterified sterols could be determined in saponified extracts. Results show that the mean phytosterol content is comparable in both cereals (whereas other lipids, such as oleic and linoleic acids, are increased in spelt wholemeal): spelt extract has, on average, 527.7 microg of free and esterified sterols g(-1) of wholemeal and 123.8 microg of glycosylated sterols g(-1) of wholemeal versus 528.5 and 112.6 microg x g(-1) in winter wheat (values not corrected for recoveries). This is the first report on the application and validation of an LC/MS2 method for the quantification of phytosterols in spelt and winter wheat.  相似文献   
67.
Recordings of the middle latency of the auditory evoked potential (MLAEP) were made in eight conscious ponies. These traces were compared to those made under halothane anaesthesia with and without paralysis of the skeletal muscles. Recordings were also made from percutaneous electrodes placed along the neck with the same stimulus used for the auditory evoked potentials. The results of these experiments were used to deduce the origin of latencies in the auditory evoked potential occurring between 10 and 25 ms after the stimulus. The MLAEP was found to contain two positive peaks between the latencies of 10 and 25 ms. The first of these two peaks was not abolished by halothane anaesthesia or muscle paralysis. The second of these two peaks was abolished by halothane anaesthesia in all but one animal. In this animal the second peak was abolished by muscle paralysis. No peaks of corresponding latency were recorded from the percutaneous electrodes except from one electrode position at the caudal neck in one pony. The first peak of the middle latency auditory evoked potential seen in conscious ponies appeared to be of central nervous orign. The second peak appeared to be of muscular origin, possibly from the external auditory muscles. The second peak may be analogous to the post-auricular waveform described in man.  相似文献   
68.
The Bowen Technique is a unique hands‐on therapy developed by Tom Bowen of Australia in the 1950s–60s and adapted for use in animals by Carol Bennett in 1997. It consists of a specific sequence of gentle, precise rolling moves done with thumb and fingers over muscle and tendon edges, across the direction of tension. A short waiting period follows each set of moves. Definitive mechanism(s) of action remains to be identified; however, autonomic nervous system modulation (heart rate variability studies) has been documented in humans. The technique has also been reported effective for back, hip, neck, and shoulder pain in human studies. Five geriatric dogs (13–16 years old) of various breeds were presented in a case series at a small animal clinic for primary complaints of stiffness, poor ambulation, and difficulty lying down/getting up. Four had hindlimb proprioceptive deficits; three had arthritic changes to coxofemoral joints and/or lumbar spine; three showed active indicators of pain (chronic pacing/panting; irritability; social withdrawal). All were on NSAID and/or nutritional therapy with unsatisfactory results. One dog had acupuncture weekly for over 1 year but no longer tolerated the needles. Treatment consisted of Animal Bowen at weekly or biweekly intervals. Three dogs were pain scored [0–10; average starting score 6.7 ± 0.6 (mean ± S.D.); range 6–7] by owner before and after treatment. All five dogs showed significant positive changes in attitude, and four had notable improvement in ease of ambulation, after the first treatment. Improvement was progressive over treatment course. Average post‐treatment score was 2.3 ± 2.1 (0, 3, 4); average pain score reduction was 4.3 ± 1.5 (range 3–6) after two to six treatments for the three dogs scored. One dog had complete resolution of hindlimb lameness of 5 years duration after three sessions. Animal Bowen, used alone or in conjunction with standard analgesics and other treatments, can be an effective therapy for chronic musculoskeletal conditions in dogs.  相似文献   
69.
Equine viral arteritis   总被引:2,自引:0,他引:2  
  相似文献   
70.
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