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71.
As part of an epidemiology study, extraction methods and extract cleanup procedures were developed and validated for polychlorinated biphenyls (PCBs) and DDE, an ubiquitous metabolite of DDT, in human milk, blood serum, and infant formula. Studies included quantitative and reproducible recovery of total lipids, and reproducible and reasonably high recoveries of these chlorinated compounds from the human body fluids and infant formula, including levels of environmental health interest. An extensive quality control and assurance program was designed for use with these methods. Some validation work on serum was done using radiolabeled 14C-Aroclor 1254. Dilution assays were developed to permit use of a constant procedure, which should minimize variability in results. Methods are based on selected organic solvent extraction and column chromatographic cleanup techniques and quantitation by electron capture gas chromatography (EC/GC). Using these extensively researched extraction and cleanup methods, the limits of detection for GC measurements were 10.0 and 2.00 ppb for PCBs and DDE, respectively, in milk and 4.00 and 0.80 ppb in serum.  相似文献   
72.
The Clinical, radiologic and echocardiographic findings in a one-year old dog with mild subvalvular aortic stenosis and aberrant caudal vena circulation are described. Aberrant systemic venous return to the right side of the heart usually has little clinical significance, but the unusual features in survey radiographs, contrast angiograms and contrast echocardiograms constitute the reasons for this report.  相似文献   
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Ohne Zusammenfassung  相似文献   
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76.
The effects of two reduced-protein diets and a canine maintenance diet on renal function, nutrition, serum and urine acid-base and electrolyte values, and divalent ion metabolism were compared in Beagle dogs with induced chronic renal failure. Two reduced-protein (18%) diets differed in their protein sources. One 18% protein diet was formulated using egg protein as the only protein source. The other 18% protein diet was formulated using a mixture of animal and vegetable proteins. The 42% protein diet contained a mixture of animal and vegetable protein sources. Results of this study indicate that the egg-based and mixed protein-based diets had similar effects on most clinical and laboratory evaluations in dogs with chronic renal failure. However, the egg protein diet appeared to promote hyperchloremic metabolic acidosis. Both reduced-protein diets were beneficial in reducing azotemia, polyuria, hypermagnesemia, and fractional excretion of phosphorus compared with the 42% protein diet.  相似文献   
77.
Two hundred and eighty foxes necropsied over a 4-year period harboured cestodes in the following order of prevalence: Taenia pisiformis, Echinococcus granulosus, T. hydatigena, T. multiceps and Dipylidium caninum. The nematodes Uncinaria stenocephala, Toxocaracanis and Toxascaris leonina, were also found. These findings are discussed in the light of other surveys.  相似文献   
78.
After a 12-hour fast, blood samples were obtained from 31 dogs with previously untreated lymphoma. Blood samples were also collected from 16 of these dogs after up to 5 treatments with doxorubicin (30 mg/m2 intravenously every 3 weeks). All 16 dogs underwent complete remission. Five dogs were re-evaluated after relapse and after overt signs of cancer cachexia had become clinically apparent. Samples were assayed for 8 quantitative parameters: total cholesterol (T-CH) and total triglyceride (T-TG) concentrations, and the concentration of cholesterol and triglyceride in each of the three major lipoprotein fractions, very-low-density lipoprotein (VLDL-CH and VLDL-TG), low-density lipoprotein (LDL-CH and LDL-TG), and high-density lipoprotein (HDL-CH and HDL-TG). The results were compared with those from 20 healthy control dogs of similar weight and age before and 3 weeks after being given one dose of doxorubicin (30 mg/m2 intravenously). The administration of doxorubicin to control dogs resulted in a significant (P> .05) decrease in T-CH, LDL-CH, and HDL-CH, as well as a significant increase in VLOL-TG and HDL-TG. When compared with untreated controls, untreated dogs with lymphoma had significantly higher concentrations of VLDL-CH, T-TG, VLDL-TG, LDL-TG, and HDL-TG, and significantly lower concentrations of HDL-CH. HDL-TG and VLDL-TG concentrations from dogs with lymphoma were significantly increased above pretreatment values after relapse and development of overt signs of cancer cachexia. Dogs in remission that were evaluated after one dose of doxorubicin had significantly higher concentrations of T-CH, VLDL-CH, T-TG, and LDL-TG when compared with controls that were evaluated after an identical dose of doxorubicin. HDL-TG increased significantly over pretreatment values in dogs with lymphoma after doxorubicin therapy. These results suggest that dogs with lymphoma have significant alterations in lipid profiles, and with the possible exception of HDL-CH, these abnormalities do not normalize when clinical remission is obtained.  相似文献   
79.
Urine protein/creatinine (UP/C) ratios and 24-hour urinary protein excretion were compared in clinically normal cats and cats with surgically induced chronic renal failure (CRF). Mean 24-hour urinary protein excretion in 30 clinically normal cats fed a 28% protein diet (dry weight basis) was 4.93 mg/kg/24-hour (SD = 1.34) with a range of 2.99 to 8.88. Mean UP/C ratio in these cats was 0.134 (SD = 0.037) with a range of 0.073 to 0.239. Mean 24-hour urinary protein excretion in CRF cats was 10.49 mg/kg/24-hour (SD = 11.28) with a range of 2.16 to 62.93. Mean UP/C ratio in the CRF cats was 0.359 (SD = 0.374) with a range of 0.061 to 1.916. Linear regression showed high correlation (R2 = 0.973, P less than 0.001) between 24-hour urinary protein excretion and UP/C ratio in clinically normal cats and cats with surgically induced chronic renal failure. The regression equation for 24-hour urinary protein excretion versus UP/C ratio was: 24-hour urinary protein excretion = 29.39 (UP/C) + 0.18. Results of this study indicate that UP/C ratios are a valid estimate of 24-hour urinary protein excretion in clinically normal and CRF cats. Dietary protein intake significantly affected UP/C ratios in clinically normal cats and cats with surgically induced CRF. Therefore, the influence of dietary protein should be considered when interpreting UP/C ratios.  相似文献   
80.
Treatment with 3 formulations of cambendazole (paste, pellets, and suspension) was compared with thiabendazole treatment in 181 Quarter Horses (females and intact and altered males) of different ages in 2 experiments. The mean output of strongyle eggs, as measured by eggs per gram of feces (epg), was reduced by at least 95% by the 3 formulations of cambendazole compared with pretreatment epg and epg in simultaneously nonmedicated horses. Eggs of Parascaris equorum were seen in 19 of the younger horses in experiment I. Parascaris eggs were not seen in postmedication fecal samples from 14 horses treated wtih cambendazole. Of the 5 horses treated with thiabendazole, 2 had postmedication Parascaris egg counts.  相似文献   
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