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31.
Disease seventy and crop yield were compared in monocultures and mixtures of two wheat cultivars. one susceptible and one resistant to Puccinia graminis f. sp. tritici. Part of each plot was inoculated and part treated with fungicide. Rust seventy was inversely related to the proportion of resistant plants present. Weight of grain in 100 heads of the susceptible cultivar increased as the amount of rust decreased. The susceptible cultivar yielded less than the resistant cultivar in monoculture, but was a stronger competitor in mixtures. Competitive abilities of the cultivars were independent of severity of rust in the mixtures studied.  相似文献   
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Pentobarbital (1.0, 1.5, and 2.0 mg/kg intravenously [IV]) was administered to four adult cows to determine a dose suitable for producing standing sedation in adult cattle, and to evaluate its effects on cardiopulmonary function and rumen motility. The response was assessed after 15, 30, 60, and 90 minutes. The 1.0 and 1.5 mg/kg doses induced mild sedation at 15 and 30 minutes, and no sedation at 60 and 90 minutes. The 2.0 mg/kg dose produced moderate sedation at 15 and 30 minutes, and mild sedation at 60 minutes. The 2.0 mg/kg dose was judged to be the most suitable. The effects of pentobarbital (2.0 mg/kg IV) on heart rate, blood pressure, respiratory rate, blood gases, and rumen motility were measured in five cows during a 90 minute period. Respiratory rate was significantly depressed at 15, 30, and 60 minutes, but there were no significant changes in the other variables. Pentobarbital (2.0 mg/kg IV) is reliable in adult cattle for standing sedation of short duration.  相似文献   
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Abstract. Isolated areas of the skin and gills of rainbow and brown trout were subjected to hyperosmotic infiltration with E. coli both in vitro and in vivo and examined for the passage of bacteria. Bacteria were recovered from the isolated gill arches only after treatment with balanced salt solution at x 10 concentration, followed by the bacterial suspension. All the skin flap experiments were negative. Bacteria were recovered from the blood offish when that part of the animal anterior to the pectoral fins was exposed to the infiltrating bacteria. They were only recovered when the animal was exposed to the full hyperosmotic infiltration schedule. The evidence strongly supports the view that the bacteria enter the animal through the gills.  相似文献   
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ABSTRACT Interest in the use of adjustment models has recently increased as analysts have come to see the value of these models in the study of regional growth processes. Adjustment models are especially useful in clarifying the nature and direction of population-employment interactions. However, other models of regional growth suggest that employment should not be treated as a single homogeneous variable, as is the usual assumption in regional adjustment models. This paper looks at the issue of employment disaggregation, and suggests that adjustment models can be alternatively specified by making use of economic base theory to separate employment into at least two broad sectors. Alternative economic base specifications are tested using data for the nonmetropolitan counties (n=254) of the US. Rocky Mountain West during a recent time period. The results show that an economic base version of the adjustment model provides insights to regional change that are not available from the traditional version of the model.  相似文献   
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ABSTRACT Economic and demographic restructuring, along with the increasing desirability of environmental amenities, have driven growth in the eight‐state region of the Rocky Mountain West to extraordinary levels in recent decades. While social scientists have developed a solid conceptual understanding of the processes driving growth and change in the region, the broad nature of the land use outcomes associated with in‐migration has not received nearly as much scholarly attention. This article initiates an in‐depth empirical investigation on the magnitude, nature, and spatial variation of land use change in the Rocky Mountain West over the 1982‐1997 time period. Data from the USDA's National Resources Inventory reveals that the conversion of landscapes from rural to urban types of land uses varies significantly from place to place, not only in terms of total land developed, but also with respect to how population pressures and a number of other local characteristics of counties manifest themselves in the spatial pattern of growth.  相似文献   
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Abstract— Skin lesions occurring in 22 dogs with leishmaniasis (Kala-azar) were studied clinically and histopathologically, so as to better characterize the range of abnormalities encountered in this disease. The main clinical dermatological patterns observed were exfoliative dermatitis (90.9 per cent of dogs), ulcerations (63.6 per cent), onychogryposis (54.5 per cent), sterile pustular dermatitis (13.6 per cent), and paronychia (13.6 per cent). Most of the dogs (86.4 per cent) had more than one type of skin lesion. The most commonly seen histopathological patterns were granulomatous perifolliculitis and sebaceous adenitis (68.2 per cent), superficial and deep perivascular dermatitis (54.5 per cent), and interstitial dermatitis (50.0 per cent). Parasites, mostly within macrophages, were detected in the skin biopsies from 50.0 per cent of the dogs. Résumé— Les lesions cutanés de 22 chiens atteints de leishmaniose ont étéétudiées cliniquement et histopathologiquement, afin de mieux caractériser les anomalies observées lors de cette maladie. La principale manifestation dermatologique observée était une dermatitie exfoliative (90,9% des chiens), des ulcérations (63,6%), une onychogriphose (54,5%) une dermite pustuleuse stérile (13,6%) et une paronychie (13,6%). La plupart des chiens (84,6%) avaient plus d'un type de lésion cutanée. Les lesions histopathologiques les plus communes étaient des périfolliculites granulomateuses et des adénites sébacées (68,2%), une dermite superficielle et profonde périvasculire (54,5%), une dermite intersticielle (50%). Les parasites, généraiement dans les macrophages, ont été isolés dans une biopsie sur deux. Zusammenfassung— Hautveränderungen, die bei 22 Hunden mit Leishmaniose (Kala-azar) auftraten, wurden klinisch und histopathologisch untersucht, um die Spannweite der Veränderungen, die bei dieser Krankheit auftreten, besser charakterisieren zu können. Als hauptsächliche klinische dermatologische Symptome wurden exfoliative Dermatitis (90,9% der Hunde), Ulzerationen (63,6%), Onychogrypose (54,5%)), sterile pustulöse Dermatitis (13,6%) und Paronychie (13,6%) beobachtet. Die meisten Hunde (86,4%) wiesen mehr als einen Typ Hautveränderung auf. Die häufigsten histopathologischen Befunde bestanden in granulomatöser Perifollikulitis und Talgdrüsenadenitis (68,2%), oberflächlicher und tiefer perivaskulärer Dermatitis (54,5%) und interstitieller Dermatitis (50,0%). Die Parasiten, die meistens in den Makrophagen liegen, wurden in den Hautbiopsien bei 50,0% der Hunde entdeckt. Resumen Se estudiarion clínica e histopatológicamente las lesiones cutáneas padecidas por 22 perros con leismaniasis (Kala-azar), con el propósito de caracterizar el rango de abnormalidades producidas por la enfermedad. La sprincipales características patológicias observadas fueron: dermatitis exfoliativa (90.9% de los perros), ulceraciones (63.6%), onicogriposis (54.5%), dermatitis postular esteril (13.6%), y paronquia (13.6%). La mayoría de los perros, (86.4%), presentaban más de un tipo de lesion dérmica. Los modelos histopatológicos reconocidos más frequentemente fueron: perifoliculitis granulomatosa y adenitis sebácea (68.2%)), dermatitis perivascular superficial y profunda (54.5%), y dermatitis intersticial (50%). Las biopsias cutáneas detectaron parásitos, la mayoría en los macrófagos, en 50% de los perros.  相似文献   
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A 4‐year‐old neutered female domestic shorthair was evaluated for mentation changes and left prosencephalic signs. This imaging report describes the imaging findings for this patient. A diagnosis of a cryptococcal mass was made based on imaging and additional diagnostics. Complete resolution of the mass was demonstrated by follow‐up imaging. This report serves as a reminder that masses associated with cryptococcal infection should be included on the differential list for cats with intracranial masses. In addition, this report provides evidence that large intracranial cryptococcal masses may resolve with long‐term medical therapy.  相似文献   
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