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121.
Profile characteristics, and form and surface activity of inorganic phosphorus in a deep red Kenya coffee soil (Nitosol) 总被引:4,自引:0,他引:4
The paper examines some of the physical and chemical properties of a deep red friable clay profile (Nitosol) developed in the Kenya highlands over trachyte. This soil is widely planted to coffee. The profile is remarkable for the depth and uniformity of the B horizon and for its stable microaggregation. Despite a clay content of 50–60% throughout the deep solum, the soil feels and handles like a loam. Work with radioactive phosphorus on samples from the profile and from nearby experimental plots under coffee showed that the activity, and the amounts, of surface phosphate fractions decreased in the order Fe-P, Al-P and Ca-P, but the order of decrease of specific surface activity was Al-P, Fe-P, Ca-P. The relative availabilities of these forms is discussed. 相似文献
122.
123.
MATTSON MARK D. GODFREY PAUL J. WALK MARIE-FRANÇOISE KERR PETER A. ZAJICEK O. THOMAS 《Water, air, and soil pollution》1997,96(1-4):211-232
A ten year survey of water quality in 330 Massachusetts streams was conducted to examine the rate and pattern of recovery from acidification. Meta-analysis was used to combine the results of the 330 non-parametric trend tests into an overall test for trend in a variety of water quality variables including pH, acid neutralizing capacity (ANC), and major inorganic ions. Analysis of trends in the raw data indicates both pH and ANC are increasing. After detrending for variations in stream runoff, we estimate the streams are recovering from acidification at a rate of +0.021 pH units/year and +2.4 μeq/L/year, for pH and ANC respectively. These trends appear to be related to declines in sulfate (–1.8 μeq/L/year), while base cation trends were mixed. Meta-analysis reveals the trends are not always homogeneous between seasons or between sites. While it is commonly assumed that the low ANC systems are most ‘sensitive’ to changes in acid or base inputs, we found the greatest rates of change in ANC were associated with the high ANC systems. The greatest increases in pH were seen in the low ANC streams as expected. The results also suggest streams respond quickly to changes in precipitation inputs and stream monitoring networks may be valuable as an early detection technique for changes in environmental quality. 相似文献
124.
CARLO B. VITALE PETER J. IHRKE† THIERRY OLIVRY† ‡ ANTHONY A. STANNARD† 《Veterinary dermatology》1996,7(4):227-233
Abstract A pruritic maculopapular eruption with clinical and histological features similar to urticaria pigmentosa of humans is reported in three related Sphinx cats. All cats shared the same grandsire, had a juvenile onset of disease, and demonstrated similar historical, clinical and histological findings. Physical examination revealed widespread bilaterally symmetrical, erythematous, partially coalescing, crusted macules and papules on the trunk, limbs, neck and head. A few macules exhibited a dark brown pigmentation. Dermatographism could not be elicited in any of the cats. Histological examination of papules revealed the présence of a perivascular to diffuse dermal and subcutaneous infiltrate of well-differentiated mast cells. In one cat where systemic involvement was pursued, evidence of internal disease was not found. Resumen Se describe en 3 gatos esfinge emparentados una erupción maculopapular pruritica con caracteristicas clinicas e histológicas similares a la urticaria pigmentosa en la especie humana. Todos los gatos compartian el mismo abuelo, desarrollaron la enfermedad en edad juvenil y mostraron hallazgos históricos, clinicos e histológicos similares. El examen fisico mostró pápulas y máculas costrosas, eritematosas, parcialmente unidas, generalizadas, bilaterales y simétricas localizadas en tronco, extremidades, cuello y cabeza. Algunas máculas mostraban una pigmentación marronácea oscura. No pudo provocarse dermatografismo en ninguno de los gatos. El examen histológico de las pápulas mostró la presencia de un infiltrado dérmico y subcutáneo perivascular a difuso compuesto por mastocitos bien diferenciados. No se encontró enfermedad sistémica en un animal en el que se evaluó esta posibilidad. [Vitale, C.B., Ihrke, P.J., Olivry, T., Stannard, A.A. Feline urticaria pigmentosa in three related Sphinx cats. (Urticaria pigmentosa felina en 3 gatos esfinge emparentados.) Veterinary Dermatology 1996; 7 : 227–233.] Résumé Les auteurs décrivent chez 3 chats Sphynx apparentés une eruption maculopapuleuse présentant des similitudes cliniques et histologiques avec l'urticaire pigmentaire humaine. Les 3 chats ont le même grandpère, présentent une apparition précoce des symptômes, et, une anamnèse, une clinique et une histologie similaires. L'examen clinique révèle des macules et des papules croûteuses à large distribution bilatérale et symétrique, érythèmateuses, partiellement coalescentes, sur le tronc, les membres, le cou et la tête. Quelques macules montrent une pigmentation brun foncé. La présence d'un dermographisme n'a pu être démontré chez aucun des chats. L'examen histologique des papules révèle la présence d'un infiltrat dermique et sous cutané périvasculaire à diffus de mastocytes bien différenciés. La recherche d'une atteinte systémique chez un des chats n'a pas montré d'atteinte interne. [Vitale, C.B., Ihrke, P.J., Olivry, T., Stannard, A.A. Feline urticaria pigmentosa in three related Sphinx cats. (Urticaire pigmentaire féline chez 3 chats Sphynx apparentés.) Veterinary Dermatology 1996; 7 : 227–233.] Zusammenfassung Es wird über eine juckende makulopapuläre Eruption mit klinischen und histologischen Befunden, die der Urticaria pigmentosa des Menschen ähneln, bei drei verwandten Sphinx-Katzen berichtet. Alle Katzen hatten den selben Großvater, zeigten einen Krankheitsbeginn im Jugendalter und wiesen ähnliche Befunde in der Vorgeschichte, Klinik und Histologie auf. Die klinische Untersuchung zeigte weit verteilte, bilateral symmetrische, erythematöse, teilweise koaleszierende verkrustete Maculae und Papeln am Rumpf, Gliedmaßen, Hais und Kopf. Einige maculae wiesen eine dunkelbraune Pigmentierung auf. Dermatographismus konnte bei keiner der Katzen ausgelöst werden. Die histologische Untersuchung der Papeln zeigte die Anwesenheit eines perivaskulären bis diffusen dermalen und subkutanen Infiltrates von gut differenzierten Mastzellen. Bei einer Katze mit systemischen Erscheinungen konnte die Ursache der inneren Erkrankung nicht gefunden werden. [Vitale, C.B., Ihrke, P.J., Olivry, T., Stannard, A.A. Feline urticaria pigmentosa in three related Sphinx cats (Feline Urticaria pigmentosa bei drei verwandten Sphinx-Katzen). Veterinary Dermatology 1996; 7 : 227–233.] 相似文献
125.
AUREA PASCAL-TENORIO THIERRY OLIVRY ¶ THELMA LEE GROSS† BARBARA A. ATLEE‡ PETER J. IHRKE§ 《Veterinary dermatology》1997,8(1):47-52
Abstract A paraneoplastic alopecia associated with internal malignancy is reported in four cats. Acute, bilaterally symmetrical, ventral glistening alopecia, weight loss and lethargy were present in all cats. Skin biopsy specimens exhibited severe follicular and adnexal atrophy with follicular miniaturization, minimal inflammation and, in many cases, absence of stratum corneum. At the time of díagnosis, three cats had a metastatic pancreatic adenocarcinoma and one had a bile duct carcinoma. This report confirms, and expands upon the previous report of a syndrome associating ventral alopecia and metastatic visceral carcinomas in cats. Résumé— Une alopécie paranéoplasique associée à une tumeur interne maligne est observée sur 4 chats. Les symptômes sont caractérisés par une alopécie symétrique et bilatérale sur le ventre avec un aspect brillant et lisse, un amaigrissement, une lethargic Les lésions histopathologiques sont caractérisées par une atrophie folliculaire et annexielle avec des petits follicules pileux, une inflammation dermique discréte et dans beaucoup de cas, une absence du stratum corneum. Trois chats présentent un adénocarcinome pancréatique métastasé et un chat un cholangiocarcinome. Ces cas confirment l'existence d'un syndrome associant une alopécie ventrale et des carcinomes viscéraux métastatiques chez le chat. [Pascal-Tenorio, A., Olivry, T., Gross, T. L., Atlee, B. A., Ihrke, P. J. Paraneoplastic alopecia associated with internal malignancies in the cat. (Alopécie paranéoplasique associée à des tumeurs malignes internes chez le chat.) Veterinary Dermatology 1997; 8 : 47–52.] Resumen Se describe en cuatro gatos una alopecia paraneoplasica asociada a procesos malignos internos. Todos los gatos presentaban una alopecia bilateral, simétrica, ventral, de aspecto brillante, pérdida de peso y letargia. Las biopsias cutáneas mostraron atrofia folicular y adnexal marcada, miniaturización de foliculos, inflamación minima y, en muchos casos, ausencia del estrato córneo. En el momento del díagnóstico, tres de los gatos tenian un adenocarcinoma metastático y uno tenia un carcinoma de conducto biliar. Este articulo confirma y amplia un informe previo sobre el sindrome de alopecia ventral y carcinomas viscerales metastáticos en gatos. [Pascal-Tenorio, A., Olivry, T., Gross, T. L., Atlee, B. A., Ihrke, P. J. Paraneoplastic alopecia associated with internal malignancies in the cat. (Alopecia paraneoplasica asociada a procesos malignos internos en el gato.) Veterinary Dermatology 1997; 8 : 47–52.] Zusammenfassung— Es wird über eine paraneoplastische Alopezie in Verbindung mit inneren malignen Prozessen bei vier Katzen berichtet. Bei alien Katzen traten eine akute bilateral symmetrische ventrale Alopezie, Gewichtsverlust und Lethargie auf. Die Hautbiopsien zeigten eine schwere follikuläre und adnexale Atrophie mit follikulärer Miniaturisation, geringer Entzündung und in vielen Fallen ein Fehlen des Stratum corneum. Zum Zeitpunkt der Diagnose litten drei Katzen an einem metastasierenden Adenokarzinom des Pankreas und eine Katze an einem Gallengangskarzinom. Dieser Bericht erhärtet und erweitert den früheren Bericht über ein Syndrom, das ventrale Alopezie in Verbindung mit metastasierenden Eingeweidekarzinomen bei der Katze beschreibt. (Paraneoplastische Alopezie in Verbindung mit inneren malignen Prozessen bei der Katze.) Veterinary Dermatology 1997; 8 : 47–52.] 相似文献
126.
ABSTRACT Unemployment rates appear to vary widely at a subregional (e.g., local or provincial) level. Using spatial econometric models for spatial autocorrelation, this paper focuses attention on the spatial structure of regional unemployment disparities of Italian provinces. On the basis of findings from the economic literature and of the available socio‐economic data, various model specifications, including different explanatory variables, are tested to investigate the geographical distribution of unemployment in the 103 provinces of Italy for the years 1998 and 2003. The results suggest that there is a clear explanation of unemployment differentials in terms of spatial equilibrium and disequilibrium factors and a significant degree of spatial dependence among labour markets at the provincial level in Italy. Provinces marked by high unemployment, as well as those characterised by low unemployment, tend to be spatially clustered, demonstrating the presence of unemployment “persistency” in space and time regimes. 相似文献
127.
Efficacy of an Epidural Combination of Morphine and Detomidine in Alleviating Experimentally Induced Hindlimb Lameness in Horses 总被引:2,自引:0,他引:2
ANNETTE M. SYSEL DVM R. SCOTT PLEASANT DVM MS Dipiomate ACVS JOHN D. JACOBSON DVM MS Dipiomate ACVA H. DAVID MOLL DVM MS Dipiomate ACVS PAULA D. MODRANSKY DVM MS LORIN D. WARNICK DVM PhD D. PHILLIP SPONENBERG DVM PhD PETER EYRE BVMS PhD MRCVS 《Veterinary surgery : VS》1996,25(6):511-518
Amphotericin B-induced synovitis of the left tarsocrural joint was used to create a grade 3 of 4 lameness in 11 horses. Caudal epidural catheters were placed and advanced to the lumbosacral region. Baseline heart and respiratory rates were recorded and horses were videotaped at a walk and trot. Morphine sulphate (0.2 mg/kg) and detomidine hydrochloride (30 μg/kg) were administered to treated horses (n = 8) through the epidural catheter; an equivalent volume of physiologic saline solution was administered to control horses (n = 3) through the catheter. At hourly intervals after epidural injection for a total of 6 hours, heart and respiratory rates were recorded, and horses were videotaped walking and trotting. At the end of the observation period, video recordings were scrambled onto a master videotape. Lamenesses were scored by three investigators unaware of group assignment or treatment time. Lameness scores, heart rates, and respiratory rates were compared between groups using repeated measures analysis of variance. There was a significant decrease in lameness score after treatment with epidural morphine and detomidine ( P =.0003); average lameness scores of treated horses were less than grade 1 at each hourly observation for 6 hours after drug administration. Early in the observation period, heart rates significantly increased in control horses and decreased in treated horses ( P =.03). A similar trend occurred for respiratory rates ( P =.07). Results of this study demonstrate that epidural administration of a combination of morphine and detomidine is capable of providing profound hindlimb analgesia in horses. 相似文献
128.
129.
PETER WOOD 《Growth and change》2006,37(3):335-361
ABSTRACT It is often assumed that future urban employment will be increasingly dependent on the knowledge‐intensive business services (KIBS). This underpins much of the current thinking about the development of the English “core cites.” Their example is employed to examine the more general validity of such assumptions, in terms of five critical questions to which research offers only partial and indefinite answers. For any city, how far are these activities really “knowledge intensive”? What markets do they serve? Is their future growth certain? And even when this is the case, how can they make a long‐term contribution to local urban economic success? Finally, how far do urban economic institutions and policies need to be adapted to foster knowledge‐based activities such as KIBS? It seems that, despite the growth of measured KIBS employment, most of the core cities possess few truly knowledge‐intensive KIBS, capable of serving national and international business markets, competitively adapting to future change, and adding to the competitiveness of the wider urban economy. Nationally such activities remain focused into the London region where, if anything, they have increased their concentration is recent years. 相似文献
130.
Localized Learning Revisited 总被引:2,自引:0,他引:2
ABSTRACT The concept of localized learning outlines how local conditions and spatial proximity between actors enable the formation of distinctive cognitive repertoires and influence the generation and selection of skills, processes, and products within a field of knowledge or activity. The localized learning argument consists of two distinct yet related elements. One has to do with localized capabilities that enhance learning, while the other concerns the possible benefits that firms with similar or related activities may accrue by locating in spatial proximity to one another. This article disentangles these two inherent elements of the concept, reviews some of the critiques that have been raised against it, and sorts out some misunderstandings that are often attached to its present use. 相似文献