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31.
A cross‐sectional study was performed on acutely vomiting dogs to compare the accuracy of radiography and ultrasonography for the diagnosis of small‐intestinal mechanical obstruction and to describe several radiographic and ultrasonographic signs to identify their contribution to the final diagnosis. The sample population consisted of 82 adult dogs and small‐intestinal obstruction by foreign body was confirmed in 27/82 (33%) dogs by surgery or necropsy. Radiography produced a definitive result (obstructed or not obstructed) in 58/82 (70%) of dogs; ultrasonography produced a definitive result in 80/82 (97%) of dogs. On radiographs, a diagnosis of obstruction was based on detection of segmental small‐intestinal dilatation, plication, or detection of a foreign body. Approximately 30% (8/27) of obstructed dogs did not have radiographic signs of segmental small‐intestinal dilatation, of which 50% (4/8) were due to linear foreign bodies. The ultrasonographic diagnosis of small‐intestinal obstruction was based on detection of an obstructive lesion, sonographic signs of plication or segmental, small‐intestinal dilatation. The ultrasonographic presence or absence of moderate‐to‐severe intestinal diameter enlargement (due to lumen dilatation) of the jejunum (>1.5 cm) was a useful discriminatory finding and, when present, should prompt a thorough search for a cause of small‐intestinal obstruction. In conclusion, both abdominal radiography and abdominal ultrasonography are accurate for diagnosing small‐intestinal obstruction in vomiting dogs and either may be used depending on availability and examiner choice. Abdominal ultrasonography had greater accuracy, fewer equivocal results and provided greater diagnostic confidence compared with radiography.  相似文献   
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Western rock lobster, Panulirus cygnus, phyllosoma were grown from hatching to stage IV. Larvae were fed with Artemia enriched with a (i) base enrichment (Base) containing 520 g kg?1 squid oil or tailor made enrichments in which oils high in polyunsaturated fatty acid (PUFA) have been added at the expense of squid oil. These treatments were (ii) base enrichment supplemented with docosahexaenoic acid (DHA) rich oil, (iii) base enrichment supplemented with arachidonic acid (AA) rich oil, or (iv) base enrichment supplemented with DHA and AA (D + A) rich oils. Total survival of phyllosoma to stage IV was high, with no significant difference between treatments (range 12.3–17.5%). By stage IV, the larvae fed the DHA or AA enriched Artemia were significantly larger (3.33 mm length) than larvae fed the Base or D + A enriched Artemia (3.18–3.24 mm length). Phyllosoma were sampled at stages II and III for biochemical analysis. The major lipid class (LC) in all phyllosoma was polar lipid (PL) (88.9–92.4%), followed by sterol (ST) (6.2–9.7%). Triacylglycerol (TAG), free fatty acid (FFA) and hydrocarbon/wax ester were minor components (≤1%) in all phyllosoma samples. In contrast, the major LC in all enrichments and enriched Artemia was TAG (76.3–85.1% and 53.4–60.2%, respectively), followed by PL (11.4–14.8% and 30.6–38.1% respectively). The main fatty acids (FA) in phyllosoma were 16:0, 18:1n‐9, 18:1n‐7, 18:0, AA, eicosapentaenoic acid (EPA) and DHA. Addition of AA, and to a lesser extent DHA, to enrichments resulted in increased levels of those FA in Artemia and phyllosoma compared with the Base enrichment. This was particularly evident for stage III larvae. Comparatively, elevated growth for phyllosoma to stage IV was achieved with DHA and AA enriched diets. Our findings highlight the importance of lipids and in particular essential long‐chain PUFA, as nutritional components for phyllosoma diets.  相似文献   
33.
 用两个DNA探针pJEL101和pBSavrxa10,测定了78个来自18个地区的水稻白叶枯病菌系的RFLP型,其中主要来自华北、东北和少数来自华中、华南,以分析其群体结构和遗传多样性。各菌系的基因组DNA分别用限制性内切酶EcoR I和BamH I酶切探针pJEL101或pBSavrxa10。通过分子杂交,分别鉴定出16种RFLP型。病原型1、2和6的多数来自华北和东北菌系表现14种RFLP型。它们之间多数只有一带之差,或有3~4个带位不同。然而,它们与来自广东和云南的菌系相比,差别较大,有7~8条带位不同。根据参试菌系的RFLP带型分簇(Cluster),如以彼此之间的带位相似率达85%为界,可分为6簇,多数病原型1、2和6的菌系为簇1,少数几个菌系,LN43、GD1358和YN5分别为簇4、5和6。参试的菌系群体遗传变异为0.77(pJEL101)和0.83(pBSavrxa10)。也分析了亚群体的各病原型内的遗传变异,初步分析表明中国的水稻白叶枯病菌系的遗传变异多种多样。但尚需测试更多的来自华南;华中和西南地区的菌系,方能较系统地分析全国菌系的群体结构及其遗传关系。  相似文献   
34.
Objective— To determine outcome after medical or surgical treatment of postpartum mares with confirmed or presumptive uterine tears. Study Design— Case series. Methods— Postpartum mares were included if foaling had occurred within 7 days and uterine tear was confirmed surgically or, in medically treated mares, by palpation or presumed based on peritonitis. Information (age, breed; physical examination, laboratory and abdominocentesis findings; treatment, survival rates, length of hospital stay, treatments costs, and breeding performance after discharge) was obtained from the medical records (1990–2007). The influence of variables was compared between medical and surgical treatment, and between survivors and nonsurvivors. Results— For 49 mares, survival was 75%, with no significant difference between medical (11/15; 73%) or surgical (26/34; 76%) treatment. Admission variables, treatment cost, duration of hospital stay, and likelihood of foaling after discharge were not significantly different between treatment groups. Nonsurvivors were significantly more likely to have gastric reflux, higher heart rate, anion gap, lower total CO2, and leukocyte count, compared with survivors. Tears were significantly (P=.018) more likely to occur in the right uterine horn than in other parts of the uterus. Conclusions— Uterine tears occur more commonly in the uterine horns, more so the right horn, and survival is similar with surgical or medical treatment of uterine tears in postpartum mares. Clinical Relevance— Medical treatment may be a reasonable alternative to surgical treatment for uterine tears, although the severity of tear that can resolve with medical treatment is unknown, and medical therapy can be as expensive as surgical treatment.  相似文献   
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NELSON CV 《Science (New York, N.Y.)》1961,133(3467):1831-1832
The spatial dipole moment of a perfused animal heart suspended at the center of a fluid-filled sphere can be found in magnitude and direction to a good approximation by three sets of bipolar measurements. The method has been applied in finding the vectorcardiograms of turtle and rabbit hearts.  相似文献   
37.
The pharmacokinetics and bioavailability of a formulation of chloramphenicol base in propylene glycol were determined following administration of single intravenous (i.v.) and subcutaneous (s.c.) 50 mg/kg doses of chloramphenicol to six non-lactating Holstein cows. Mean serum concentrations of chloramphenicol following i.v. administration of 50 mg/kg declined rapidly from a peak of greater than 100 micrograms/ml to 6.9 micrograms/ml at 12 h after administration. Serum concentrations were not detectable at 24 h after administration. The curve of serum concentrations vs time was characteristic of a two-compartment open model. Mean i.v. data gave a biological half-life of 4.3 h and a volume of distribution of the central compartment of 0.44 l/kg. Serum concentrations of chloramphenicol following s.c. administration of 50 mg/kg rose slowly to a broad peak near 20 micrograms/ml from 3 to 8 h after administration and then declined. These data were also analysed according to a two-compartment open model. The biological half-life was 4.2 h and the volume of distribution of the central compartment was 0.50 l/kg. Significant adverse reactions, including acute collapse, intravascular haemolysis and haemoglobinuria, were observed in cows when dosed i.v. Cows dosed s.c. exhibited local reactions at injection sites. The disadvantages of administration of 50 mg/kg doses of chloramphenicol base in propylene glycol appear to be significant and may outweight the potential advantages of parenteral use of the drug as presently formulated.  相似文献   
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Field portable X-ray fluorescence (PXRF) spectrometry has become an increasingly popular technique for in-situ elemental characterization of soils. The technique is fast, portable, and accurate, requiring minimal sample preparation and no consumables. However, soil moisture 〉 20% has been known to cause fluorescence denudation and error in elemental reporting and few studies have evaluated the presence of soil moisture in solid form as ice. Gelisols (USDA Soil Taxonomy), permafrost-affected soils, cover a large amount of the land surface in the northern and southern hemispheres. Thus, the applicability of PXRF in those areas requires further investigation. PXRF was used to scan the elemental composition (Ba, Ca, Cr, Fe, K, Mn, Pb, Rb, Sr, Ti, Zn, and Zr) of 13 pedons in central and northern Alaska, USA. Four types of scans were completed: 1) in-situ frozen soil, 2) re-frozen soil in the laboratory, 3) melted soil/water mixture in the laboratory, and 4) moisture-corrected soil. All were then compared to oven dry soil scans. Results showed that the majority of PXRF readings from in-situ, re-frozen, and melted samples were significantly underestimated, compared to the readings on oven dry samples, owing to the interference expected by moisture. However, when the moisture contents were divided into 〉 40% and 〈 40〈 groups, the PXRF readings under different scanning conditions performed better in the group with 〈 40% moisture contents. Most elements of the scans on the melted samples with 〈 40% moisture contents acceptably compared to those of the dry samples, with R2 values ranging from 0.446 (Mn) to 0.930 (St). However, underestimation of the melted samples was still quite apparent. Moisture-corrected sample PXRF readings provided the best correlation to those of the dry, ground samples as indicated by higher R2 values, lower root mean square errors (RMSEs), and slopes closer to 1 in linear regression equations. However, the in-situ (frozen) sample scans did not differ appreciably from the melted sample scans in their correlations to dry sample scans in terms of R2 values (0.81 vs. 0.88), RMSEs (1.06 vs. 0.85), and slopes (0.88 vs. 0.92). Notably, all of those relationships improved for the group with moisture contents 〈 40%.  相似文献   
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