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11.
12.
This study was carried out to evaluate the effects of organophosphate (OP) insecticide chlorpyrifos on cardiac morphology and function in rabbits using echocardiography. Twenty New Zealand male rabbits were divided equally into four groups. Rabbits were exposed to chlorpyrifos in drinking water at concentrations of 0, 125, 250 or 375 ppm for 90 days. The comparison among the groups indicated that 375 ppm chlorpyrifos resulted in significant decrease (p<0.05) in heart rate (HR), cardiac output (CO), left ventricular fractional shortening (FS), left ventricular ejection fraction (EF), percentage thickening of left ventricle posterior wall (PWT), and significant increase (p<0.05) in left atrial diameter (LA), left ventricular internal diameter in end diastole (LVIDD), left ventricular end diastolic (EDV) and end systolic volumes (ESV) compared to those of the control group. These results showed that chlorpyrifos induces cardiac dysfunction in rabbits.  相似文献   
13.
The plasma disposition of fenbendazole (FBZ), oxfendazole (OFZ) and albendazole (ABZ); and the enantiospecific disposition of OFZ, and ABZSO produced were investigated following an oral administration (50 mg/kg) in dogs. Blood samples were collected from 1 to 120 h post-administration. The plasma samples were analysed by high performance liquid chromatography (HPLC). The plasma concentration of FBZ, OFZ, ABZ and their metabolites were significantly different from each other and depended on the drug administered. The sulphone metabolite (FBZSO2) of FBZ was not detected in any plasma samples and the parent molecule ABZ did not reach quantifiable concentrations following FBZ and ABZ administration, respectively. OFZ and its sulphone metabolite attained a significantly higher plasma concentration and remained much longer in plasma compared with FBZ and ABZ and their respective metabolites. The maximum plasma concentrations (Cmax), area under the concentration time curve (AUC) and mean residence time (MRT) of parent OFZ were more than 30, 68 and 2 times those of FBZ, respectively. The same parameters for ABZSO were also significantly greater than those of FBZSO. The ratio for total AUCs of both the parent drug and the metabolites were 1:42:7 for following FBZ, OFZ and ABZ administration, respectively. The enantiomers were never in racemic proportions and (+) enantiomers of both OFZ and ABZSO were predominant in plasma. The AUC of (+) enantiomers of OFZ and ABZSO was, respectively more than three and seven times larger than that of (-) enantiomers of both molecules. It is concluded that the plasma concentration of OFZ was substantially greater compared with FBZ and ABZ. The data on the pharmacokinetic profile of OFZ presented here may contribute to evaluate its potential as an anthelmintic drug for parasite control in dogs.  相似文献   
14.
Despite several experiments on row spacings and seeding rates of grain soybeans, limited information is available on the most suitable row spacing and seeding rate for tall and robust forage type soybeans grown for seed. The objectives of this study were to investigate seed yield, oil and protein content, and several morphological traits as affected by row spacing (20, 40, 60 and 80 cm) and seeding rate (330,000, 660,000, 990,000 and 1,320,000 seeds ha−1) in tall and robust forage type soybeans in three irrigated Mediterranean environments in Turkey in a randomized split plot design with three replications in 2004 and 2005. Row spacings had no significant effect on plant height but tall and profusely branched plants developed in wide row spacing and light seeding conditions. Seed yield responded positively and linearly to row spacing up to 60 cm and then decreased slightly in all locations. Seed yield was the highest at 990,000 seeds ha−1 seeding rate in all three locations (3072.5 kg ha−1 in Bursa LSD = 214.7 kg ha−1, 3295.1 kg ha−1 in Mustafakemalpasa LSD = 298.6 kg ha−1 and 3311.3 kg ha−1 in Samsun LSD = 321.1 kg ha−1). Averaged across years, locations, row spacings, and seeding rates the mean seed yield was an impressive 3013.4 kg ha−1 compare with 3500.0 kg ha−1 average seed yield of grain types. Crude protein and oil content of forage type soybean were not significantly affected by row spacings and seeding rates. It was concluded that forage type soybeans can be grown for multiple purposes at the 990,000 seeds ha−1 seeding rate and 60 cm row spacings in Mediterranean environments.  相似文献   
15.
A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni0.8Fe0.2, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2.  相似文献   
16.
Sixty white male mice were used in this study. Three groups, each comprising 20 mice were established. The control group (Group 1) was provided ad libitum pellet feed. On the other hand, the experimental groups, namely, Groups 2 and 3 were given pellet feed containing deltamethrin throughout the day, so that the animals were administered doses of 7.5 and 30 mg/kg/body weight/day, respectively. Blood samples were collected from all groups on the 15th, 30th, 45th, and 60th days of the experiment for measurement of serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), alcaline phosphatase (ALP), amylase and cholinesterase activities, and levels of glucose, urea, creatinine, triglyceride, cholesterol, calcium, phosphor, sodium, potassium, and chloride. According to data obtained, on the 15th day of the study, compared to the control group, statistically significant increase in urea, cholesterol, ALP, cholinesterase, calcium, and potassium levels/activities, and significant decrease in SGOT activity and chloride levels in Group 2, and significant increase in cholesterol, ALP, cholinesterase, calcium, potassium and chloride levels/activities in Group 3, and significant decrease in SGOT activity in Group 3 were determined. On the 30th day of the study, in comparison to the control group, triglyceride and cholesterol levels and ALP activity were determined to be significantly increased in the Group 2, whereas SGOT activity were significantly reduced in Group 2, and triglyceride and cholesterol levels were demonstrated to be significantly increased and SGOT activity was significantly reduced in Group 3. On the 45th day of the study, compared to the controls, significant increase in cholesterol and sodium levels, and significant decrease in triglyceride levels and ALP activity in Group 2, significant increase in creatinine, cholesterol and sodium levels and cholinesterase activity, and significant decrease in glucose, SGPT, ALP and phosphor levels/activities were detected in Group 3. On the 60th day, in other words, in the last period of the study, ALP activity, and triglyceride, calcium, and phosphor levels were determined to be significantly increased and significant decrease in amylase activity in Group 2. Furthermore, significant increase in triglyceride, ALP, amylase, calcium, phosphor, and potassium levels/activities, and significant decrease in glucose and creatinine levels were observed in Group 3. However no correlation was determined to exist between the changes were found to be statistically significant, and the administration dose and duration of deltamethrin in all periods and groups.  相似文献   
17.
Many factors related with drug and animals affect the plasma disposition of endectocides including ivermectin (IVM). The aim of the present study was to investigate the breed differences in pharmacokinetics of IVM in goats following subcutaneous administration. Two different goat breeds (Kilis and Damascus goats) were allocated into two treatment groups with respect to breed. The injectable formulation of IVM was administered subcutaneously at a dose rate of 0.2 mg/kg bodyweight. Blood samples were collected before treatment and at various times between 1 h and 40 days after treatment and the plasma samples were analysed by high performance liquid chromatography (HPLC) using fluorescence detection. The results indicated that the plasma disposition of IVM was substantially affected by breed differences following subcutaneous administration in goats. The last detectable plasma concentration (tlast) of IVM was significantly later in Kilis goats (38.33 days) compared with Damascus goats (22.50 days). Although, there were no significant differences on Cmax (10.83 ng/ml vs. 10.15 ng/ml) and tmax (2.75 days vs. 2.33 days) values; the area under the concentration–time curve-AUC (110.26 ng.d/ml vs. 73.38 ng.d/ml) the terminal half-life-t1/2λz (5.65 days vs. 3.81 days) and the mean plasma residence time-MRT (9.31 days vs. 6.35 days) were significantly different in Kilis goats compared with Damascus goats, respectively. The breed-related difference observed on the plasma disposition of IVM between Kilis and Damascus goats could be attributable to different excretion pattern or specific anatomical and/or physiological characteristics such as body fat composition of each breed.  相似文献   
18.
Objective  To establish reference values for activated coagulation time (ACT) in normal cats and dogs, by visual assessment of clot formation using the MAX-ACTTM tube.
Subjects  We recruited 43 cats and 50 dogs for the study; 11 cats and 4 dogs were excluded from the statistical analysis because of abnormalities on clinical examination or laboratory testing including anaemia, prolonged prothrombin time (PT) or activated partial thromboplastin time (APTT), or insufficient plasma volume for comprehensive laboratory coagulation testing.
Procedure  Blood samples were collected via direct venipuncture for MAX-ACT, packed cell volume/total solids, manual platelet estimation and PT/APTT measurement. Blood (0.5 mL) was mixed gently in the MAX-ACT tube at 37°C for 30 s, then assessed for clot formation every 5 to 10 s by tipping the tube gently on its side and monitoring for magnet movement. The endpoint was defined as the magnet lodging in the clot. The technique was tested with 10 dogs by collecting two blood samples from the same needle insertion and running a MAX-ACT on each simultaneously.
Results  In normal cats the mean MAX-ACT was 66 s (range 55–85 s). In normal dogs the mean was 71 s (range 55–80 s). There was no statistical difference between the first and second samples collected from the same needle insertion.
Conclusions and Clinical Relevance  In both cats and dogs, a MAX-ACT result >85 s should be considered abnormal and further coagulation testing should be performed. Additionally, failure to discard the first few drops of the sample does not appear to significantly affect results.  相似文献   
19.
A two-year irrigated field study was conducted to determine the effects of plant growth-promoting rhizobacteria (PGPR; Bacillus subtilis OSU-142 and Bacillus megaterium M3) as biofertilizer, and in combination with a chemical nitrogen (N) fertilizer, on turf color and clipping yield, and interaction of biofertilizer and chemical N fertilizers in perennial ryegrass (Lolium perenne L.), tall fescue (Festuca arundinacea L. Schreb.), and Kentucky bluegrass (Poa pratensis L.). The three turf species were tested separately in split-plot design experiments with three replications. Three fertilizer sources (ammonium nitrate only, ammonium nitrate + B. megaterium M3, and ammonium nitrate + B. subtilis OSU-142) were the main plots. N applications with monthly applications of 0.0, 2.5, 5.0, and 7.5 g N/m2 were the subplots. Color ratings and clipping yields increased with increasing chemical N fertilizers in all species. Both Bacillus sp. significantly increased color ratings and clipping yields in perennial ryegrass and tall fescue. However, there were no significant differences among the three fertilizer sources in color and clipping yield of Kentucky bluegrass. The experiments showed that there is a small but significant benefit from applying biofertilizers for turf color, and that N fertilization may be reduced in some turf species when biofertilization are made for this purpose.  相似文献   
20.
对快速生长的鸡和火鸡限制其生长期的活动是导致绿肌病的原因。绿肌病在较为年长的鸡尤其多发 ,而在幼鸡则常不被注意 ,尤其是在以胴体或分割块的形式出售时。然而 ,在去骨加工时则多见绿肌病  相似文献   
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