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441.
A retrospective epidemiologic study evaluated 1,129 feline intestinal tumor patients via data entered into the Veterinary Medical Database (VMDB) from 1964 to 2004. Cases were analyzed by breed, age, yr of diagnosis, tumor type, and location. The VMDB incidence of all intestinal tumors reported during this 40 yr period was 0.4%, with small intestinal tumors predominating. The most common intestinal tumor was lymphoma, but the most common nonlymphoid tumor was adenocarcinoma. The Siamese breed and increasing age after 7 yr conferred an increased risk. Intact males and females appeared to have a decreased risk compared with neutered patients, but this may be explained by the age difference among these patients as older patients were more likely to be neutered. Prospective studies evaluating neuter status predilection and prognosis are warranted.  相似文献   
442.
This retrospective study describes 68 alpacas with skin diseases investigated from 1997 through 2006 at Cornell University. During this time period, 40 of 715 (5.6%) alpacas presented to the university hospital had dermatological diseases. In addition, skin‐biopsy specimens accounted for 86 of 353 (24.4%) of alpaca biopsy specimens submitted to the diagnostic laboratory, and of these 86 specimens, follow‐up was available for 28 cases. The following diseases were most common: bacterial infections (22%); neoplasms, cysts and hamartomas (19%); presumed immunological disorders (12%); and ectoparasitisms (10%). Conditions described for the first time included intertrigo, collagen and hair follicle hamartomas, lymphoma, hybrid follicular cysts, melanocytoma, anagen defluxion, telogen defluxion, presumed insect‐bite hypersensitivity, ichthyosis, and possible hereditary bilateral aural haematomas and chondritis. The results of the retrospective study are compared and contrasted with the results of a literature review.  相似文献   
443.
Health screening of potential canine breeding stock can provide invaluable information to allow breeders to select against inherited diseases in their breeding programmes. This review details the screening programmes that are currently available to UK dog breeders and evaluates their impact as selective tools for dog breeders.  相似文献   
444.
Empirical data generated from fire scars are a foundation for understanding fire regimes, designing land-management objectives, and addressing long-term land-use and climate-change effects. We derived precise dates of historic fires from fire-scar injuries occurring on trees growing in a relict post oak woodland in northeastern Texas. The fire-event chronology shows the last three centuries were marked with human influence, with an overall trend of decreasing fire occurrence through time. Thirty different fire events occurred between 1690 and 2007, of which 26 occurred prior to 1856. All fires occurred while trees were dormant. From 1690 to 1820, the mean fire interval was 6.7 yr. A 50-yr period without fire occurred in the latter 19th century (1855–1905) and coincided with the establishment of an oak cohort. A second extended period (80 yr) without fire characterized most of the 20th century. We hypothesize that the absence of fire during much of the last century has resulted in increased tree density and canopy closure, the establishment of fire-intolerant vines, shrubs, and trees, and likely the decline of fire-dependent plant species. Information describing long-term changes of fire regimes in oak woodlands in this region could aid in determining fire-management objectives with respect to prescribed fire implementation and community restoration.  相似文献   
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