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51.
OBJECTIVES: To report the diagnosis and outcome after surgical correction of bilateral distal ureteral anomalies in a Standardbred filly. STUDY DESIGN: Clinical case report. ANIMAL: An 8-month-old, 310 kg Standardbred filly with left ureteral atresia and right ureteral ectopia. METHODS: The filly was admitted for evaluation of incontinence since birth and severe urine scalding of the hindquarters. Diagnosis was made by both direct (cystoscopy and vaginoscopy) and indirect (intravenous pyelography, ultrasonography, and scintigraphy) evaluation of the ureters and bladder. The filly had left ureteral atresia, hydronephrosis, and decreased left-sided renal function and right ureteral ectopia before surgery. Surgical correction was performed on the left by an end-to-side stapled anastomosis technique and on the right by a side-to-side hand-sewn anastomosis technique. RESULTS: Surgical correction was successful. The filly had no postoperative complications and remained continent 18 months after surgery. Left renal function improved. CONCLUSION: Ureteral anomalies can be successfully repaired in larger (>300 kg) foals and some renal function may be restored after surgical correction. CLINICAL RELEVANCE: Scintigraphy should be considered in diagnosis of ureteral anomalies, assessing renal function, and determining prognosis for horses with hydronephrosis caused by ureteral ectopia and atresia.  相似文献   
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Sustained challenges by third world, black and feminist scholars have unsettled the established agenda of the social sciences in the 1990s. Unfortunately, population geographies in the Pacific have failed to engage with these debates. By avoiding the metaphysical challenges posed by contemporary theoretical debates, often by people from previously marginalised groups, population geographies have failed to provide the spark necessary for the dynamic expansion of ideas. However, an analysis of population geographies in the Pacific, almost all of which are mobility studies, reveals important contributions for advancing a more critical population geography. This paper begins with a critical review of population geography in general then looks more specifically at population geographies, mostly mobility studies, in the Pacific. It advances the argument that the humanist geographers Chapman and Bonnemaison have made critical contributions in reconceptualising population mobility. Further advances would benefit from an engagement with feminist geography and post-structural discourse analysis.  相似文献   
54.
A market survey and review of government statistics were carried out to establish imports and exports of marine ornamental fishes into and out of Hong Kong, and to examine the local trade in terms of volume, value and species composition. Official government import figures for marine aquarium fishes were available from 1984 to 1991 and from 1997 and 1998. When compared with net imports, export and re-export volumes over the 15-year period were small, indicating that most imports entered the local market, or were exported unrecorded. The market survey of marine aquarium shops in Hong Kong was carried out between August 1996 and January 1997. From this survey, an annual estimate of 957,563 coral reef fish was calculated for the local trade, valued at HK$57,453,780, with a mean retail price of HK$60 per fish. These figures account for an estimated 2–3% of the global value and volume of marine aquarium fish trade, according to 1992 figures and, compared with government figures, indicate that official declarations of imports are underreported by at least 2–3 fold. A total of 342 marine aquarium fish species, from 49 families, were recorded with about 60% belonging to the families Labridae, Chaetodontidae, Pomacanthidae and Pomacentridae. It was estimated that a large proportion of the trade was in juvenile fishes and almost all fish were less than 10cm in standard length. It was common to see fishes in poor condition, species hard to maintain in captivity, or those listed for conservation concern, on sale. There are no regulations for local traders of live marine fishes other than those relating to either protected species or animal welfare. Licensing of traders in marine fishes could be introduced under existing Hong Kong legislation if fishes were to be re-classified as animals. This is strongly recommended as a step towards regulating and managing the trade in Hong Kong.  相似文献   
55.
Reef fishes are significant socially, nutritionally and economically, yet biologically they are vulnerable to both over‐exploitation and degradation of their habitat. Their importance in the tropics for living conditions, human health, food security and economic development is enormous, with millions of people and hundreds of thousands of communities directly dependent, and many more indirectly so. Reef fish fisheries are also critical safety valves in times of economic or social hardship or disturbance, and are more efficient, less wasteful and support far more livelihoods per tonne produced than industrial scale fisheries. Yet, relative to other fisheries globally, those associated with coral reefs are under‐managed, under‐funded, under‐monitored, and as a consequence, poorly understood or little regarded by national governments. Even among non‐governmental organizations, which are increasingly active in tropical marine issues, there is typically little focus on reef‐associated resources, the interest being more on biodiversity per se or protection of coral reef habitat. This essay explores the background and history to this situation, examines fishery trends over the last 30 years, and charts a possible way forward given the current realities of funding, capacity, development patterns and scientific understanding of coral reef ecosystems. The luxury live reef food‐fish trade is used throughout as a case study because it exemplifies many of the problems and challenges of attaining sustainable use of coral reef‐associated resources. The thesis developed is that sustaining reef fish fisheries and conserving biodiversity can be complementary, rather than contradictory, in terms of yield from reef systems. I identify changes in perspectives needed to move forward, suggest that we must be cautious of ‘fashionable’ solutions or apparent ‘quick fixes’, and argue that fundamental decisions must be made concerning the short and long‐term values of coral reef‐associated resources, particularly fish, for food and cash and regarding alternative sources of protein. Not to address the problems will inevitably lead to growing poverty, hardship and social unrest in many areas.  相似文献   
56.
Previous studies on the transport and absorption of resveratrol (3,5,4-O-trihydroxystilbene) were done using the pure compound. In this study, the absorption of resveratrol in digested peanut micellar from boiled and roasted peanuts was investigated using a human intestinal Caco-2 cell monolayer. The amount transported and rate of transport of both resveratrol glycosides and its hydrolytic product were quantified by a reverse-phase high-performance liquid chromatography method with mass spectrometric detection. Four peaks were identified in the digested peanut micellar of both boiled and roasted peanuts: two resveratrol glycosides, one resveratrol diglycoside, and possibly an acylated resveratrol glycoside. Resveratrol from roasted peanut micellar had a higher transport rate than those from the boiled peanut. This implies that resveratrol from roasted peanut is better absorbed than from boiled peanut. Also, the rate of transport and amount of resveratrol transported were higher for the hydrolytic product than the nonhydrolyzed glycosides. This has strong implications for in vivo absorption as the enzymatic activity of gut microflora could enhance the bioavailability of β-glycosides of dietary polyphenols.  相似文献   
57.
This study investigated the production of polyclonal (pAB) antibodies and the first time production of monoclonal (mAB) antibodies against the mycotoxin alternariol, and their implementation in enzyme immunoassay (EIA) for the rapid determination of alternariol in foods. Both EIAs were highly sensitive, with detection limits (IC??) of 35 ± 6.9 pg/mL (mAb EIA) and 59 ± 16 pg/mL (pAb EIA). Food products (n = 109; apple and tomato products, white wine) from German retail shops were analyzed. At a detection limit of 1-2 μg/kg, alternariol at 1-13 μg/kg was found with high frequency in apple (67%) and tomato (93%) products. Tomatoes with visible signs of Alternaria infection, stored at room temperature for up to 4 weeks, contained alternariol at levels up to 50 mg/kg, as determined by EIA and HPLC-FLD. It is concluded that the alternariol immunoassays present a versatile screening tool which could facilitate food control for Alternaria toxins.  相似文献   
58.
A 10‐year‐old entire female Beagle dog was evaluated for an acute history of lethargy, anorexia, and diarrhea. Mammary tumors were detected during physical examination. Ultrasonographic scanning revealed the presence of a unique pattern of multiple, well‐defined and well‐marginated hypoechoic nodules in the muscularis layer of the jejunum. These nodules were not associated with changes in the rest of the normal intestinal layering and were not causing signs of intestinal obstruction. Mammary carcinoma metastases to the intestinal muscularis layer were diagnosed based on histopathological examination.  相似文献   
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Productivity is a poor predictor of plant species richness   总被引:5,自引:0,他引:5  
For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses questioned the generality of hump-shaped patterns, these syntheses have been criticized for failing to account for methodological differences among studies. We addressed such concerns by conducting standardized sampling in 48 herbaceous-dominated plant communities on five continents. We found no clear relationship between productivity and fine-scale (meters(-2)) richness within sites, within regions, or across the globe. Ecologists should focus on fresh, mechanistic approaches to understanding the multivariate links between productivity and richness.  相似文献   
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