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1.
Paradoxical, concurrent hyper-and hyporeactivity of a profound nature to specific stimuli occurred when 10 micrograms of morphine was microinjected bilaterally into the periaqueductal gray matter of the rat brain. Both effects at this site were dose-dependent. The hyperreactivity (to previously neutral auditory and visual stimuli) was obtained only with intracerebrally injected morphine and never with intraperitoneally injected morphine or with other opiates administered either way. Rapid tolerance to toxic doses of morphine developed at this site, as well as cross tolerance of the hyporeactivity to painful stimuli between routes (intracerebral to intraperitoneal) of morphine administration. Both the hyper- and hyporeactivity were fully reversible by intracerebral injection of naloxone in the periaqueductal gray. Thus, the periaqueductal gray appears to be a major pathway for morphine action.  相似文献   
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OBJECTIVE: To report a technique for minimally invasive occlusion of patent ductus arteriosus (PDA) and outcome in 5 dogs. STUDY DESIGN: Clinical cases. Animals: Five, 4-6-month-old, dogs with PDA. MATERIALS AND METHODS: Titanium ligating clips were used for PDA closure in all dogs. Three dogs had video-enhanced mini-thoracotomy PDA occlusion. Two other dogs had thoracoscopic PDA occlusion using a custom-designed thoracoscopy clip applicator. RESULTS: Thoracoscopic PDA occlusion was successful in both dogs in which it was attempted. Complete PDA closure was achieved in 4 dogs. Three months after surgery, the largest dog had residual ductal flow that hemodynamically was insignificant. CONCLUSIONS: Although technically demanding, minimally invasive PDA occlusion is a safe and reliable technique in dogs. Preoperative measurement of the diameter of the PDA is crucial to determine if complete closure with metal clips can be achieved. CLINICAL RELEVANCE: Minimally invasive PDA occlusion should be considered as an alternative to occlusion via conventional thoracotomy.  相似文献   
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? Context

Forests are important carbon sinks, but increasing temperatures may favour increases in insect populations, resulting in greater damage to trees. This, in turn, would lead to lower levels of carbon sequestration, intensifying global warming.

? Aim

It is therefore important to predict the impact of insect defoliation on tree growth accurately. The main insect defoliators of conifers in Southern Europe and North Africa are pine and cedar processionary moths (Lepidoptera, Thaumetopoeidae).

? Method

We conducted a meta-analysis based on 45 study cases, to estimate the effect of processionary moth defoliation on tree growth.

? Result

Overall, processionary moth defoliation had a significant impact on tree growth, regardless of the tree and moth species considered. Mean relative tree growth loss increased with the rate of defoliation levelling out at ca. 50?%; it was significantly larger for young than for old trees.

? Conclusion

These results suggest that estimates of processionary moth defoliation could easily be incorporated into tree growth models, to predict the effect of processionary moth outbreaks on carbon sequestration in Mediterranean forests.  相似文献   
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A Box-Behnken experimental design and response surface methodology were employed to optimize the pretreatment parameters of a formic/acetic acid delignification treatment of Miscanthus × giganteus for enzymatic hydrolysis. The effects of three independent variables, namely cooking time (1, 2 and 3 h), formic acid/acetic acid/water ratio (20/60/20, 30/50/20 and 40/40/20) and temperature (80, 90 and 107 °C) on pulp yield, residual Klason lignin content, concentration of degradation products (furfural and hydroxymethylfurfural) in the black liquor, and enzymatic digestibility of the pulps were investigated. The major parameter influencing was the temperature for pulp yield, delignification degree, furfural production and enzymatic digestibility. According to the response surface analysis the optimum conditions predicted for a maximum enzymatic digestibility of the glucan (75.3%) would be obtained using a cooking time of 3 h, at 107 °C and with a formic acid/acetic acid/water ratio of 40/40/20%. Glucan digestibility was highly dependent on the delignification degree.  相似文献   
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Toxigenic cyanobacteria are photosynthetic prokaryotes that are most often recognized in marine and freshwater systems, such as lakes, ponds, rivers, and estuaries. When environmental conditions (such as light, nutrients, water column stability, etc.) are suitable for their growth, cyanobacteria may proliferate and form toxic blooms in the upper, sunlit layers. The biology and ecology of cyanobacteria have been extensively studied throughout the world during the last two decades, but we still know little about the factors and processes involved in regulating toxin production for many cyanobacterial species. In this minireview, we discuss these microorganisms, and more especially the toxins they produce, as a potential and important health risk for wild and domestic animals.  相似文献   
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Rhodococcus equi is the most common infectious cause of mortality in foals between 1 and 6 months of age. Because of an increase in the number of antibiotic-resistant strains, the optimization of a prophylactic strategy is a key factor in the comprehensive management of R. equi pneumonia.The objectives of this study were to assess the safety and immunogenicity of R. equi-secreted proteins (ReSP) co-administered with either the nanoparticular adjuvant Montanide? IMS 3012 VG, or a new polymeric adjuvant Montanide? PET GEL A, and to further investigate the most immunogenic proteins for subsequent immunization/challenge experiments in the development of a vaccine against rhodoccocal pneumonia. The approach involved two phases. The first phase aimed to investigate the safety of vaccination in six adult horses. The second phase aimed to determine the safety and immunogenicity of vaccination in twelve 3-week-old foals.We set out to develop a method based on ultrasound measurements for safety assessment in adult horses in order to evaluate any in situ changes at the injection site, in the skin or the underlying muscle, with quantitative and qualitative data revealing that administration of ReSP combined with the Pet Gel A adjuvant led to an increase in local inflammation, associated with 4- to 7-fold higher levels of anti-R. equi IgGa, IgGb and IgGT, compared to administration of ReSP associated with IMS 3012 adjuvant, but without any impact on animal demeanor. Investigations were then performed in foals with serological and clinical follow-up until 6 months of age. Interestingly, we observed in foals a much lower incidence of adverse local tissue reactions at the injection site than in adult horses, with transient and moderate swelling for the group that received ReSP combined with Pet Gel A. Immunized foals with Pet Gel A adjuvant exhibited a similar response in both IgGa and IgGT levels, but a lower response in IgGb levels, compared to adult horses, with a subisotype profile that may however reflect a bias favorable to R. equi resistance. From the crude extract of secreted proteins, dot-blot screening enabled identification of cholesterol oxidase, mycolyl transferase 3, and PSP (probable secreted protein) as the most immunogenic candidates. Taken together, these results are encouraging in developing a vaccine for foals.  相似文献   
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