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41.
A study of amoxicillin pharmacokinetics was conducted in healthy goats and goats with chronic lead intoxication. The intoxicated goats had increased serum concentrations of liver enzymes (alanine aminotransferase and γ-glutamyl transferase), blood urea nitrogen, and reactivated δ-aminolevulinic acid dehydratase compared to the controls. Following intravenous amoxicillin (10 mg/kg bw) in control and lead-intoxicated goats, elimination half-lives were 4.14 and 1.26 h, respectively. The volumes of distribution based on the terminal phase were 1.19 and 0.38 L/kg, respectively, and those at steady-state were 0.54 and 0.18 L/kg, respectively. After intramuscular (IM) amoxicillin (10 mg/kg bw) in lead-intoxicated goats and control animals, the absorption, distribution, and elimination of the drug were more rapid in lead-intoxicated goats than the controls. Peak serum concentrations of 21.89 and 12.19 µg/mL were achieved at 1 h and 2 h, respectively, in lead-intoxicated and control goats. Amoxicillin bioavailability in the lead-intoxicated goats decreased 20% compared to the controls. After amoxicillin, more of the drug was excreted in the urine from lead-intoxicated goats than the controls. Our results suggested that lead intoxication in goats increases the rate of amoxicillin absorption after IM administration and distribution and elimination. Thus, lead intoxication may impair the therapeutic effectiveness of amoxicillin.  相似文献   
42.
Twenty-four client-owned dogs with histologically diagnosed appendicular osteosarcoma (OSA) and no evidence of gross metastatic disease were treated with amputation or limb salvage followed by combination chemotherapy consisting of carboplatin (175mg/ m2 IV, day 1) and doxorubicin (15 mg/m2 IV, day 2) given on a 21-day cycle for a maximum of 4 cycles. Hematologic and gastrointestinal adverse effects were graded according to National Cancer Institute guidelines. Thoracic radiographs were obtained before the 3rd chemotherapy cycle and then every 2 months. Median disease-free interval was 195 days (95% confidence interval 111-228 days) and median survival was 235 days (95% confidence interval 150-283 days). Two patients required dose reductions: 1 for grade 3 thrombocytopenia and 1 for grade 3 adverse gastrointestinal effects. Patients with a longer duration of clinical signs before definitive diagnosis and surgery (greater than 30 days) were more likely to develop progressive disease and to die or be euthanized because of progressive disease on any day; hazard ratios were 3.0 (P = .02) and 3.7 (P .02), respectively. In conclusion, although this combination chemotherapy protocol was well tolerated, it did not provide any improvement over historical single-agent protocols.  相似文献   
43.
Medical-records of 22 large-breed dogs (>15 kg) with osteosarcoma (OSA) of the axial skeleton were reviewed to determine prevalence of metastasis and survival associated with this neoplasm. All dogs were treated with more than 1 mode of therapy including palliative radiation (n = 12), definitive radiation (n = 8), surgery (n = 7), chemotherapy (n = 12), or some combination of these therapies. Metastasis was documented in 10 of 22 dogs (46%), and the median survival for all dogs was 137 days. Primary cause of death was local tumor recurrence (54%). Breed (retriever versus purebred versus mixed-breed survival was 100, 182, and 264 days, respectively) and radiation therapy protocol (survival in dogs treated with palliative radiation therapy versus those treated with definitive radiation therapy was 79 and 265 days, respectively) were significantly related to survival (P < .05). Prevalence of metastasis and median survival for large-breed dogs with axial skeleton OSA seems to be similar to that reported for large-breed dogs with appendicular skeleton OSA. Definitive radiation therapy may have a role in the treatment of axial skeleton osteosarcoma.  相似文献   
44.
The reaction of fumonisin B(1) with the reducing sugar D-glucose can block the primary amine group of fumonisin B(1) and may detoxify this mycotoxin. A method to separate hundred milligram quantities of fumonisin B(1)-glucose reaction products from the excess D-glucose with a reversed-phase C(18) cartridge was developed. Mass spectrometry revealed that there were four primary products in this chain reaction when fumonisin B(1) was heated with D-glucose at 65 degrees C for 48 h: N-methyl-fumonisin B(1), N-carboxymethyl-fumonisin B(1), N-(3-hydroxyacetonyl)-fumonisin B(1), and N-(2-hydroxy, 2-carboxyethyl)-fumonisin B(1). The N-(1-deoxy-D-fructos-1-yl) fumonisin B(1) (fumonisin B(1)-glucose Schiff's base) was detected by mass spectrometry when fumonisin B(1) was heated with D-glucose at 60 degrees C. The nonenzymatic browning reaction of fumonisin B(1) with excess D-glucose followed apparent first-order kinetics. The activation energy, E(a), was 105.7 kJ/mol. Fumonisin B(1) in contaminated corn could precipitate the nonenzymatic browning reaction with 0.1 M D-glucose at 60 and 80 degrees C.  相似文献   
45.
46.
Aspergillosis is an important cause of morbidity and mortality in birds. Turkey poults are known to be particularly susceptible to fungal infection. Although the respiratory tract is the most commonly affected, dissemination can occur into virtually any organ. Here, we report an unusual outbreak of articular aspergillosis in a flock of meat turkeys with clinical signs of lameness. Between 7 and 11 weeks of age, turkeys had severe granulomatous osteoarthritis of the hip joints with necrosis of the femur head. Fungal morphology and PCR amplification and sequencing of the first ITS1-5.8S-ITS2 rDNA region identified Aspergillus fumigatus as the infectious agent. Concurrently, Staphylococcus spp. was isolated from the hip joints, which may have promoted the tropism of the fungus. Mild respiratory tract aspergillosis was observed in only one case. The findings suggest that fungal arthritis may present a specific disease entity in turkeys and should be considered as further cause of lameness in turkeys.  相似文献   
47.
In the analysis of old-growth forest dynamics, the continuous process of tree aging and forest structural change is split up into several distinct forest development stages. The criteria for distinguishing the stages vary among the different approaches. In most of them, vertical canopy heterogeneity is only coarsely addressed and horizontal forest structure is quantified at spatial scales far exceeding the size of conventional forest inventory plots. In order to describe and analyze the complex mosaic structure of temperate old-growth forests with objective and quantitative measures in the context of forest inventories, we propose the Development Stage Index I DS . It employs two easily measured stand structural parameters (stem density and basal area) for quantifying the abundance of trees in three conventionally recognized tree diameter classes (premature ?<?40 cm; mature 40–70 cm; and over-mature?≥?70 cm) in plots of 500 m2 size, systematically distributed in the forest. This allows quantifying the spatial extension of the Initial, Optimum and Terminal stages of forest development at plot, stand and landscape levels. Based on thorough stand structural analyses in three virgin beech (Fagus sylvatica) forests in Slovakia, we demonstrate that I DS is a promising tool for (1) quantifying the proportion of the three stages on different scales, (2) visualizing the complex mixing of stages, and (3) analyzing dynamic changes in old-growth forest structure. We conclude that the Development Stage Index has the potential to improve the empirical foundation of forest dynamics research and to allow this discipline to proceed to more rigorous hypothesis testing.  相似文献   
48.
Lotus corniculatus and Lotus uliginosus are agronomically important forage crops used in ruminant livestock production. The condensed tannin (CT) content, dry matter (DM) production, and persistence of these species are key characteristics of interest for future exploitation of these crops. Here we present field data on 19 varieties of L. corniculatus, 2 varieties of L. uliginosus and, additionally, a glasshouse experiment using 6 varieties of L. corniculatus and 2 varieties of L. uliginosus. Current methods for the quantification of condensed tannins in crop species are slow and labor intensive and are generally based upon polymer hydrolysis following the extraction of chlorophyll in a liquid phase. Presented here is a high-throughput protocol for condensed tannin quantification suitable for microtiter plates based upon the precipitation of condensed tannin polymers in complex with bovine serum albumin (BSA) with subsequent hydrolysis of precipates using butan 1-ol/ hydrochloric acid.  相似文献   
49.
Histomonosis is a severe disease caused by the protozoan parasite Histomonas (H.) meleagridis, which can lead to high losses in turkeys. The present report describes the reoccurrence of histomonosis in a turkey breeder farm. The first outbreak occurred in 2005 in 17 weeks old hens, the second in 2009 in 8 weeks old hens. The disease remained restricted in one house and one compartment, respectively. Mortality rose to 26 and 65% respectively within few days in spite of therapy with various compounds. Both flocks had to be euthanized. In both cases H. meleagridis belonging to genotype A was detected. The source of infection remained unclear in both cases.  相似文献   
50.
Tetsuya  Kobayashi  DVM  Marlene L.  Hauck  DVM  PhD  Richard  Dodge  MS  Rodney L.  Page  DVM  MS  G. Sylvester  Price  DVM  PhD  Laurel E.  Williams  DVM  Elizabeth M.  Hardie  DVM  PhD  Kyle G.  Mathews  DVM  MS  Donald E.  Thrall  DVM  PhD 《Veterinary radiology & ultrasound》2002,43(5):473-479
Medical records for 92 cats with a vaccine associated sarcoma receiving preoperative irradiation, with or without chemotherapy, between December 1985 and September 1998 were reviewed. The purposes were to quantify response to treatment and to attempt identification of factors associated with favorable response. Variables evaluated for a relationship to outcome included signalment, tumor location, presence of gross vs. microscopic tumor, radiation field size, irradiation technique, type of surgical procedure, completeness of excision, and chemotherapy (none, carboplatin alone, and others). Time to first event was calculated for the first day of treatment until local tumor recurrence or metastasis, or the date of euthanasia or death. Median time to first event for all 92 cats was 584 days. Only completeness of surgical excision was related to the time to first event. Median time to first event in cats having complete surgical excision was 986 days compared to 292 days for cats with incomplete excision (P = 0.004). Cats requiring bone removal to effect tumor removal had earlier failure than cats having other types of surgery. There was not a significant relationship between administration of chemotherapy or chemotherapy type and time to first event although outcome in cats receiving carboplatin was better than all other treatment groups. Carboplatin addition to preoperative irradiation appears worthy of further study. Preoperative irradiation is an effective treatment for cats with vaccine associated sarcoma, especially if complete excision can be accomplished following irradiation.  相似文献   
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