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1.
Plasma cell myelomas in horses have been reported infrequently. Data from 10 cases, 9 from the literature and 1 new case, are used to characterize the disease in the horse. Hot-blooded horses (7/10), specifically Quarter Horses (4/10), were most often affected. Median age at diagnosis was 11 years (range, 3 mo-22 yr) and both male (5) and female horses (5) were represented equally. Clinical findings included weight loss (6/8), anorexia (4/8), fever (4/8), limb edema (4/8), pneumonia (3/8), rear leg paresis/ataxia (3/8), epistaxis (3/8), palpable lymphadenopathy (2/8), and bone pain (2/8). Anemia (8/8) was present routinely, and in three horses, RBCs were macrocytic. Leukopenia (2/8), thrombocy-topenia (2/8), and circulating plasma cells (3/8) were variable findings. Except for abnormal protein concentrations and hyponatremia (3), abnormal results from serum biochemical analysis including hypo-cholesterolemia (1), hypercalcemia (1), and azotemia (1) were reported infrequently. Hyperproteinemia (8/9), hypoalbuminemia (7/9), and hyperglobulinemia (8/9) were characteristic but not invariable findings. Monoclonal proteins (7/7) were detected in the α2, β, or γ region by serum electrophoresis. The paraprotein's heavy chain, determined in four horses, was a subclass of IgG. Three horses had decreased concentrations of normal immunoglobulins. Variable proteinuria (trace to 4+) was detected by routine urinalysis in four of six horses. Bence Jones proteinuria was detected in one of five horses (heat precipitation) and monoclonal proteins were detected in two of three electrophoresed urine samples. Three of the horses had lytic bone lesions detected radiographically. Bone marrow aspirates were diagnostic in two of five horses. Atypical plasma cells or increased numbers of plasma cells or both were present in histologic sections of bone marrow in six of eight horses. Common extraosseous sites of plasma cell infiltration included lymph nodes (8/8), kidney (5/8), spleen (5/8), liver (3/8), lung (3/8), brain (2/8), and orbit (2/8). Two horses had intracellular and extracellular crystalline deposits.  相似文献   
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The objectives of the present study were to quantify the effects of a biological chronic stressor (lameness) on the duration and frequency of different oestrous behaviours in parallel with milk hormone profiles. Dairy cows 51.8 ± 1.4 days postpartum (n = 59), including 18 non‐lame control cows, were scored for lameness and closely observed for signs of oestrus having had their follicular phases synchronized by administration of gonadotrophin‐releasing‐hormone (GnRH) followed by prostaglandin F (PG) 7 days later. Lameness shortened the period when herd‐mates attempted to mount the lame cows (1.83 ± 0.69 h vs 5.20 ± 1.53 h; p = 0.042) but did not affect the overall duration of total behaviours (lame 12.3 ± 1.3 h vs non‐lame 15.2 ± 1.3 h). Lameness also lowered the intensity of oestrus [1417 ± 206 points (n = 18) vs 2260 ± 307 points (n = 15); p = 0.029]. Throughout the synchronized oestrous period, lame cows mounted the rear of herd‐mates less frequently (p = 0.020) and tended to chin rest less (p = 0.075). Around the period of maximum oestrous intensity, lameness also diminished the proportion of cows mounting the rear of another cow and chin resting (p = 0.048, p = 0.037, respectively). Furthermore, lame cows had lower progesterone values during the 6 days before oestrous (p ≤ 0.05). Fewer lame cows were observed in oestrus following PG (non‐lame 83%, lame 53%; p = 0.030); however, if prior progesterone concentrations were elevated, lame cows were just as likely to be observed in oestrus. In conclusion, following endogenous progesterone exposure, lameness shortens the period when herd‐mates attempt to mount lame cows but does not affect the incidence of oestrous. However, lame cows are mounted less frequently and express oestrus of lower intensity. This is associated with lower progesterone prior to oestrus but not with abnormal oestradiol or cortisol profiles in daily milk samples.  相似文献   
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HiMag is an experimental cultivar derived from Missouri 96 (Mo96) and Kentucky 31 (K31) tall fescue (Festuca arundinacea Schreb.) parentage for increased calcium (Ca), magnesium (Mg), and reduced potassium (K)/ (Ca+Mg). Our objective was to determine productivity and mineral characteristics of endophyte‐free (E‐) HiMag in relation to standard tall fescue cultivars when grown in the Southern Piedmont Land Resource Area. In experiment 1, HiMag (E‐) and K31 (E‐) were grown at two levels of phosphorus (P), K, and lime additions to both severely eroded, and non‐eroded Cecil soil (clayey, kaolinitic, thermic family of Typic Hapludults). Herbage Ca and Mg were greater and K/(Ca+ Mg) and yield were less for HiMag than for K31. Phosphorus and K concentrations were not different. Herbage yields, P, Ca, and Mg concentrations were increased by P, K, and lime additions. In experiment 2, HiMag(E‐), K31(E‐), endophyte‐infected K31(E+), Mo I(E+), Mo II (E+), and AU Triumph (E‐) were planted either in a prepared seedbed or planted without tillage into the Cecil soil. HiMag yields were not different from Mo‐I, Mo‐II or K31(E±), but were less than those of AU Triumph (E‐). HiMag yield response to no‐till planting, past soil erosion, and fertilizer level was similar to that of K31 (E±). Fertilizer level, and soil condition affected the magnitude of differences in mineral levels in HiMag and K31 (E±), but K/(Ca+Mg) values were more favorable in HiMag. All tall fescue cultivars established equally well in no‐till or prepared seedbeds. Aside from a slightly lower first harvest yield there were no important effects of planting no‐till versus planting in a prepared seedbed. HiMag's agronomic attributes, while not superior to other cultivars, were sufficient to justify further testing to improve Mg nutrition of grazing animals.  相似文献   
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Root curvature response to unilaterally applied calcium (Ca2+) in agar was inhibited 81% by erythrosine B (EB) (10 nM) in sorghum [Sorghum bicolor (L.) Moench.] cv Funk G522DR, 70% in cv SC283, and 11% in cv SC574. EB (10 nM) is reported to totally inhibit Ca2+‐ATPase, while 10–50 μM EB is required to inhibit H+‐ATPase. Therefore, differences in relative concentrations of Ca2+‐ATPase and H+‐ATPase exist in the root plasma membranes (PM) of the three cultivars. Carbon dioxide (14CO2) production from glycerol‐tri‐(1‐14C)‐palmitate by wheat (Triticum aestivum L.) leaf rust (Puccinia recondita Rob. ex Desm.) urediospore germlings was inhibited 85% by EB (10 nM).  相似文献   
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 The diffuse-reflectance laser-flash photolysis method together with ground state diffuse reflectance spectroscopy have been used to study the effect of pH and temperature of the hydrogen peroxide treatment on oxygen delignified softwood kraft pulp. Received 20 December 1999  相似文献   
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In a 10-year retrospective study, we evaluated the clinicopathologic features and renal immunofluorescence patterns of glomerulonephritis in 41 dogs. On the basis of results of histologic examinations, the dogs were segregated into 3 groups, including membranous (n = 12), mesangioproliferative (n = 15), or membranoproliferative glomerulonephritis (n = 14). No significant differences existed among groups in regard to age or duration of illness. Most dogs had been ill for one month or longer. The proportion of dogs with azotemia, anemia, and hyperphosphatemia were not different among the disease groups. Proportion of dogs with hypoalbuminemia and the severity of hypoalbuminemia were not different among groups. Highest urine protein losses and 24-hour urine protein/creatinine ratios developed in dogs with membranous glomerulonephritis. Although hypoalbuminemia and hypercholesterolemia were common (49%), the formation of edema or ascites was not (15%) and, therefore, few dogs had all of the classic features of the nephrotic syndrome. Few dogs suffered thromboembolic complications. Antinuclear antibody titers developed in 11 dogs, the highest titers developing in dogs with polyarthritis and systemic lupus erythematosis. Cellulose acetate electrophoresis detected alpha 2 and beta 1 globulin spikes in most dogs (87%). Results of renal immunofluorescence testing were positive in 36 dogs, using polyvalent antisera for immunoglobulins (Ig)G, IgA, IgM, and/or antisera for complement factor C3. When monovalent antisera for IgG, IgA, and IgM, and fibrinogen were used, immunofluorescence was not observed as often. The major fluorescent pattern was discrete multifocal segmental granular glomerular fluorescence, consistent with immune-complex deposition. Two dogs had linear glomerular staining patterns; however, antibodies directed against normal glomerular basement membrane were not found via elution studies. A high prevalence of glucocorticoid excess (treatment with glucocorticoids and spontaneous hyperadrenocorticism) (34%), chronic inflammatory skin disease (27%), neoplasia (17%), polyarthritis (12%), and systemic lupus erythematosis (7%) were observed as clinical problems concurrent with glomerulonephritis. In 5 dogs, treatment of glomerulonephritis with prednisolone (0.5 to 1.1 mg/kg) did not result in beneficial effects and in fact appeared to be detrimental, leading to azotemia and worsening proteinuria and physical condition in some of the dogs.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
10.
A 4-year-old cow initially examined because of hindlimb lameness had a waxing and waning course of illness for 31 weeks. Signs included lameness, swelling of the affected limb, and intermittent fever, and anorexia. Radiography and bacterial culturing suggested osteomyelitis. Terminally, there was peracute anemia and dyspnea. The final diagnosis was hemangiosarcoma of the metatarsus, with metastasis to the lungs.  相似文献   
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