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11.
In this paper we estimate alternative models of the growth rate of real housing investment for Japan, Korea, Taiwan, and the U.S. Pure time series models generally provide superior fit to these growth rate data both within and out of the sample period. These time series models are then used to forecast investment growth rates in other countries. The results indicate that such time series models can be used to provide reasonable accurate forecasts for other countries. 相似文献
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ABSTRACT Information and Communication Technology (ICT) has become an important tool to promote a variety of public goals and policies. In the past years much attention has been given to the expected social benefits from deploying ICTs in different urban fields (transportation, education, public participation in planning, etc.) and to its potential to mitigate various current or emerging urban problems. The growing importance of ICTs in daily life, business activities, and governance prompts the need to consider ICTs more explicitly in urban policies. Alongside the expectation that the private sector will play a major role in the ICT field, the expected benefits from ICTs also encourage urban authorities to formulate proper public ICT policies. Against this background, various intriguing research questions arise. What are the urban policy‐makers’ expectations about ICTs? And how do they assess the future implications of ICTs for their city? A thorough analysis of these questions will provide a better understanding of the extent to which urban authorities are willing to invest in and to adopt a dedicated ICT policy. This study is focusing on the way urban decision‐makers perceive the opportunities of ICT policy. After a sketch of recent development and policy issues, a conceptual model is developed to map out the driving forces of urban ICT policies in cities in Europe. Next, by highlighting the importance of understanding the decision‐maker's “black box,” three crucial variables are identified within this box. In the remaining part of the paper these three variables will be operationalized by using a large survey comprising more than 200 European cities. By means of statistical multivariate methods (i.e., factor and cluster analysis), the decision‐makers were able to be characterized according to the way they perceive their city (the concept of “imaginable city”), their opinion about ICT, and the way they assess the relevance of ICT policies to their city. Next, a solid explanatory framework will be offered by using a log‐linear logit analysis to test the relationships between these three aspects. 相似文献
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ABSTRACT The persistence of the grass balds of the southern Appalachians represents an ecological enigma and a conservation dilemma. These high altitude treeless expanses, well known to native Americans and later grazed by white settlers, are now undergoing rapid succession which threatens a unique community of plants and animals. Whatever the balds' origin and in spite of the apparent antiquity of some, much of the botanical literature insists that they are largely an artifact of relatively recent human disturbance, and, except for rare plant preservation, deserve only limited conservation effort. Such an interpretation lacks both a historical perspective and an appreciation of the possible dynamic nature of this community. The presence of both rare, endemic plants and northern relicts requiring open habitat suggests a long evolutionary history. Also, balds that are still grazed today have maintained both their biota and size. We suggest that some balds are indeed ancient and were maintained during the late Pleistocene by mammalian herbivores. Excavations at Saltville, Virginia and elsewhere reveal the presence of up to 20 species of large herbivores, including mammoth, mastodon, bison, horse, tapir, musk ox, and ground sloth until 10,000 years ago. Thereafter, the mountains supported bison, elk, and deer until European settlement. It is likely that, as in many other parts of the world, this special natural community is the result of long-term plant-animal interactions and thus worthy of preservation. Such preservation might best be affected by the use of wild and/or domestic herbivores. 相似文献
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DON A. HULSE dvm Diplomateacvs DOUG MILLER PhD DON ROBERTS dvm PhD PETER SHIRES bvsc mrcvs Dipiomateacvs H. SHOJI md 《Veterinary surgery : VS》1986,15(4):284-288
Femoral trochleoplasties resurfaced with autogenous free periosteal grafts in six dogs were compared to femoral trochleoplasties performed without grafts in six dogs. The grafts produced cartilage as early as 4 weeks after surgery; however, it was fibrocartilage rather than normal hyaline articular cartilage. The trochleoplasties not resurfaced with periosteum also healed with fibrocartilage but not until 40 weeks postoperatively. The grafted stifles had less patellar cartilage damage when compared to trochleoplasties left to heal without resurfacing. 相似文献
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Abstract The mineral analyses of nails from 32 normal dogs were determined by atomic absorption spectrophotometry or colorimetrically. Data were compared with the mineral analyses of nails from 21 cases of idiopathic canine onychomadesis. German Shepherd dogs were significantly over represented (P < 0.005) in the affected group compared with a reference hospital population. Significant increases in the concentration of calcium (P < 0.05), potassium (P < 0.05), sodium (P < 0.0005) and phosphorus (P < 0.05) were found in nails from affected dogs compared with nails from normal animals. The mineral composition of nails from affected German Shepherd dogs was significantly different from that of affected non-German Shepherd dogs. Normal ranges for the mineral concentrations of normal canine nail are presented for the first time. The different composition of nails from affected German Shepherd dogs compared with nails from other breeds suggests a different aetiology to the onychomadesis, although the cause of the problem remains speculative. Résumé— Des analyses d'ongles de 32 chiens sains ont été déterminées par spectrophotométrie d'absorption atomique ou colométrie. Celles-ci ont été comparées avec celles d'ongles de 21 chiens à onychomadèse idiopathique. Les Bergers allemands sont surreprésentés (P < 0,005) dans le groupe de chiens malades, comparativement à la population de référence. Des augmentations significatives de la concentration de calcium (P < 0,05), de potassium (P < 0,05), de sodium (P < 0,005) et de phosphore (P < 0,05) sont notées dans les ongles des Bergers allemands à onychomadèse idiopathique, par rapport à celles des ongles des chiens atteints, mais non de race Berger allemand. Des valeurs usuelles des concentrations minérales des ongles du chien sont présentées pour la première fois. La composition différente des ongles des Bergers allemands affectés comparéeà celle des ongles des autres races affectées suggère une étiologie différente de l'onychomadèse dans cette race, bien que la cause reste encore imprècise. [Harvey, R. G., Markwell, P. J. The mineral composition of nails in normal dogs and comparison with shed nails in canine idiopathic onychomadesis (Composition minérale des ongles de chiens sains et comparaison avec celle des ongles provenant de chiens à onychomadèse idiopathique). Veterinary Dermatology 1996; 7 : 29–34.] Resumen El análisis mineral de las uñas de 32 perros normales se determinó por espectrofotometría atómica de absorción o colorimétricamente. La información se comparó con los análisis de 21 casos de onicomadesis idiopática canina. Los perros Pastor Aleman estaban significativamente sobrerepresentados (P < 0.005) en el grupo afectado comparado con la población de un hospital de referencia. Se encontraron aumentos significativos en la concentración de calcio (P < 0.05), potasio (P < 0.00005) y fósforo (P < 0.05) en la población afectada, comparado con uñas de animales normales. La composicón mineral de uñas de perros Pastor Alemán afectados fue significativamente distinta de la de los perros no Pastor Alemán afectados. Se presenta por primera vez los valores de las concentración mineral de las uñas normales en el perro. La composición distinta de las uñas de perros Pastor Alemán afectados comparadda con uñas de otras razas sugiere una etiología distinta de la onicomadesis, aunque la causa del problema continúa siendo motivo de especulación. [Harvey, R. G., Markwell, P. J. The mineral composition of nails in normal dogs and comparison with shed nails in canine idiopathic onychomadesis (Composición mineral de las uñas de perros normales comparada con la uñas eliminadas en la onicomadesis idiopática canina). Veterinary Dermatology 1996; 7 : 29–34.] Zusammenfassung— Die Mineralstoffanalyse der Krallen von 32 gesunden Hunden wurde mit Atomabsorptionsspektrometrie oder Kolorimetrie durchgeführt. Die Daten wurden mit Mineralstoffanalysen von Krallen aus 21 Fällen von idiopathischer kaniner Onychomadesis verglichen. Deutsche Schäferhunde waren signifikant überrepräsentiert (P < 0,005) in der betroffenen Gruppen im Vergleich zur einer Referenzpopulation der Klinik. Signifikante Anstiege in der Konzentration von Kalzium (P < 0,05), Kalium (P < 0,05), Natrium (P < 0,0005) und Phosphor (P < 0,05) wurden in den Krallen der betroffener Hunde im Vergleich zu denen gesunder gefunden. Die Mineralstoffzusammensetzung der Krallen betroffener Deutscher Schäferhunde unterschied sich signifikant von der betroffener Hunde anderer Rassen. Referenzbereiche für die Mineralstoffkonzentrationen gesunder Hundekrallen werden erstmalig vorgestellt. Die verschiedene Zusammensetzung der Krallen betroffener Deutscher Schäferhunde im Vergleich zu den Krallen anderer Rassen legt eine unterschiedliche Ätiologie der Onychomadesis nahe, obwohl die Ursache der Störung spekulativ bleibt. [Harvey, R. G., Markwell, P. J. The mineral composition of nails in normal dogs and comparison with shed nails in canine idiopathic onychomadesis (Die Mineralstoffzusammensetzung der krallen gesunder Hunde im Verleich zu abgesto ßenen Krallen bei kaniner idiopathischer Onychomadesis). Veterinary Dermatology 1996; 7 : 29–34.] 相似文献
17.
Congenital urethral sphincter mechanism incompetence is a cause of urinary incontinence in female dogs and cats. In some of these animals, urethra hypoplasia is the primary diagnosis, with the urethra being almost absent in some patients. Treatment of this problem can be difficult. This paper describes two techniques for the surgical treatment of eight cats and one dog with severe urethral hypoplasia. In five animals, partial excision of the bladder neck was performed to create a longer "urethra." In the other four, an attempt was made to conserve bladder volume while simultaneously creating a urethra with a bladder neck flap reconstruction technique. One cat was lost to follow-up, but the clinical signs resolved in three cats and the remaining animals improved. Two cats had recurring cystitis, possibly associated with bladder neck diverticula because of uterine horn remnants terminating abnormally in the bladder. The results in this limited series suggest that reconstructive surgery in cases of severe urethral hypoplasia improves continence control. 相似文献
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Choledocholithiasis in the dog; a review and a report of a case with rupture of the common bile duct
Cholelithiasis is the presence of concretions in the gall bladder or bile duct. The veterinary literature is reviewed and a case reported. The subject was a seven-year-old male Schnauzer with presenting signs of depression, dehydration, pyrexia, icterus, vomiting and diarrhoea. Laboratory evaluation revealed a marked neutrophilia and elevation of SGPT and BUN. A radiopaque cholelith was seen on an abdominal X-ray. Euthanasia was requested because of the patient's poor condition. On post mortem examination, local peritonitis and abscess formation around the common bile duct were occluding the outflow of bile and causing adhesions to small and large intestine. The cholelith was analysed and was found to consist mainly of calcium bilirubinate. 相似文献