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Acemannan, a complex carbohydrate shown to stimulate interleukin-1, tumor necrosis factor alpha and prostaglandin E2 production by macrophages, has also demonstrated antiviral activity in vitro against human immunodeficiency virus, Newcastle disease virus and influenza virus. A pilot study was undertaken to determine acemannan's effect in 49 feline immunodeficiency virus (FIV) infected cats with clinical signs of disease (Stage 3, 4 or 5), 23 of which had severe lymphopenia. Cats received acemannan either by intravenous (Group 1) or subcutaneous (Group 2) injection once weekly for 12 weeks, or by daily oral (Group 3) administration for 12 weeks. Upon entry into the study, cats were randomly assigned to one of the three groups. Laboratory analyses were performed at the beginning of the study and at Weeks 6 and 12. Cats were allowed to continue with a predetermined maintenance regimen of acemannan after completing the 12-week study. Thirteen cats died during the course of treatment. Upon necropsy, the most frequent histopathologic findings were neoplastic, kidney and pancreatic disease. Friedman's two-way ANOVA test showed no significant differences in efficacy among groups administered acemannan by the different routes. Therefore, groups were combined and a signed-ranks test was used to determine changes over time. A significant increase was seen in lymphocyte counts (P < 0.001). Neutrophil counts decreased significantly (P = 0.007), as did incidence of sepsis (P = 0.008). When cats entering with lymphopenia were analyzed separately, a much greater increase in lymphocyte counts was noted (235%) compared with non-lymphopenic cats (42%). A survival rate of 75% was found for all three groups. Thirty-six of 49 animals are alive 5-19 months post-entry. These results suggest that acemannan therapy may be of significant benefit in FIV-infected cats exhibiting clinical signs of disease.  相似文献   
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One dog and 2 cats were evaluated because of multiple progressively enlarging cutaneous vascular plaques. Biopsies were performed and revealed small well-circumscribed dermal nodules of dilated fully enclosed blood-filled spaces lined by single layers of endothelial cells aligned on thin fibrous walls, with minimal mitotic activity. A diagnosis of cutaneous angiomatosis was made in all 3 animals. Cutaneous angiomatosis is a progressive proliferative lesion of vascular tissue involving the dermis and subcutaneous tissues of dogs and cats. Lasers of selected wavelengths have been used to induce photothermal coagulation of hemoglobin-containing cutaneous lesions in humans; argon-pumped dye and neodymium:yttrium-aluminum-garnet lasers were used to treat the cutaneous lesions in the animals of this report. Laser treatment may provide an alternative to wide surgical resection or limb amputation for management of this condition in veterinary patients.  相似文献   
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Sea duck populations are declining in Alaska. The reasons for the decline are not known; environmental lead exposure is one suspected cause. Thirty wild Steller's eider ducks (Polysticta stelleri) and 40 wild black scoter ducks (Melanitta nigra) were tested for blood lead levels using a portable blood lead analyzer (LeadCare; ESA, Inc., Chelmsford, Massachusetts 01824, USA). Sixty-seven and one-tenth percent of the sea ducks had undetectable blood lead levels, 30.0% had values indicating normal or background lead exposure, and 2.9% had values indicating lead exposure. None of the birds had values indicating lead toxicity, and no birds demonstrated clinical signs of toxicity. Birds in areas with higher human population density had higher blood lead levels than those in less densely populated areas. This is the first time a portable blood lead analyzer has been utilized with sea ducks in a field setting. Because it provides immediate results, it is valuable as a screening tool for investigators carrying out surgical procedures on birds in the field as well as establishing baseline blood lead data on sea ducks. Lead exposure does occur in wild sea ducks, and the study indicates that additional research is needed in order to determine the role environmental lead plays in declining sea duck populations.  相似文献   
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Paclitaxel is a commonly used chemotherapeutic agent with a broad spectrum of activity against cancers in humans. In 1992, paclitaxel was approved by the U.S. Food and Drug Administration (FDA) as Taxol® for use in advanced ovarian cancer. Two years later, it was approved for the treatment of metastatic breast cancer. Paclitaxel was originally isolated from the bark of the Pacific yew tree, Taxus brevifolia in 1971. Taxanes are a family of microtubule inhibitors. As a member of this family, paclitaxel suppresses spindle microtubule dynamics. This activity results in the blockage of the metaphase‐anaphase transitions, and ultimately in the inhibition of mitosis, and induction of apoptosis in a wide spectrum of cancer cells. Additional anticancer activities of paclitaxel have been defined that are independent of these effects on the microtubules and may include the suppression of cell proliferation as well as antiangiogenic effects. Based on its targeting of a fundamental feature of the cancer phenotype, the mitotic complex, it is not surprising that paclitaxel has been found to be active in a wide variety of cancers in humans. This review summarizes the evidence in support of paclitaxel's broad anticancer activity and introduces the rationale for, and the progress in development of novel formulations of paclitaxel that may preferentially target cancers and that are not associated with the risks for hypersensitivity in dogs. Of note, a novel nanoparticle formulation of paclitaxel that substantially limits hypersensitivity was recently given conditional approval by the FDA Center for Veterinary Medicine for use in dogs with resectable and nonresectable squamous cell carcinoma and nonresectable stage III, IV and V mammary carcinoma.  相似文献   
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In the process of exploring ways to intensify crayfish culture, a growout system of individual cages (cells) was designed to determine the effects of gender and cell size on the growth of the red claw crayfish Cherax quadricarinatus. Cells of three different diameters—large (25 cm), medium (20 cm) and small (16 cm)—were used. When crayfish were stocked at a mean weight of approximately 10 g, growth rate of males was significantly higher than that of females. The growth rate of the males in the large cells was 0.31±0.14 g/day, while that of the females was 0.18±0.09 g/day. The size of the cell had significant influence on the weight of males. Male crayfish in the large and medium cells grew better than those in the small cells. When males were stocked at a higher mean weight (about 23 g), their mean weight after 206 days was higher in the large cells (69.28±15.72 g) than in the small cells (58.11±12.66 g), suggesting that the growth of large males was also affected by cell size. Regardless of cell size, male animals of this species grew faster than females under conditions of individual cells. This intensive culture method appears to present a powerful improvement in yields, by as much as two orders of magnitude, in comparison with communal cultures.  相似文献   
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