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81.
Chronic toxicity and/or oncogenicity studies were conducted in rats, mice, and dogs with the insect repellent DEET. DEET was mixed in the diet and administered to CD rats for two years at concentrations that corresponded to dosage levels of 10, 30 or 100 mg/kg/day for males and 30, 100, or 400 mg/kg/day for females; to CD-1 mice for 18 months at dosage levels of 250, 500, or 1000 mg/kg/day; and to dogs for one year, via gelatin capsules, at dosage levels of 30, 100, or 400 mg/kg/day. In the rodent studies, each group consisted of 60 animals of each sex, and two concurrent independent control groups, each containing 60 animals/sex were included in each study. Each group in the dog study consisted of four male and four female dogs and one control group was included in the study. Treatment-related effects were observed at the highest dose level in all three studies. For rats, the effects included decreases in body weight and food consumption and an increase in serum cholesterol in females only. In mice, the effects observed were decreases in body weight and food consumption in both sexes. The effects observed in dogs included increased incidences of emesis and ptyalism, and levels of transient reduction in hemoglobin and hematocrit, increased alkaline phosphatase (males only), decreased cholesterol, and increased potassium. One male dog in the high-dose group also exhibited ataxia, tremors, abnormal head movements, and/or convulsions on several occasions during the study. The highest no- observed-effect levels (NO-ELs) for rats, mice and dogs were determined to be 100, 500, and 100 mg/kg/day, respectively. No specific target organ toxicity or oncogenicity was observed in any of the studies.   相似文献   
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Plant fats are low in saturated fats but high in unsaturated fats compared to animal fats, and are supposedly less obesogenic. This study compared the obesogenic effects of plant and animal derived fatty diets in Wistar rats. Rats of each gender were divided into three dietary (standard chow (SC), high fat diet rich in animal fat (HFDaf) and a high fat diet rich in plant fat (HFDpf)) groups of ten each and fed for 17 weeks. Anthropometric, Adiposity and nutritive variables were assessed using standard methods. Comparing HFDpf to HFDaf: Abdominal circumference (AC),initial feed intaken (IFI), final feed intake(FFI), final body weight (FBW), white adipose tissue (WAT) were increased but brown adipose tissue (BAT) decreased in male rats fed with HFDpf; also, there were increased body length, IFI, FFI but decreased AC, FBW, BAT in female rats fed with HFDpf. Comparing male to female rats: Thoracic circumference, IFI, FFI, energy intake were increased while Adiposity index decreased across diet groups in male rats; the AC, FBW increased while WAT, BAT decreased in HFDpf fed group, also, BAT was increased but AC, FBW decreased in HFDaf fed group in male rats. Palatability and high feed efficiency of consumed diets were more associated with obesogenic risk than just the level of saturation. Therefore, Obesogenic effects of fatty diets in both genders is more dependent on the quantity (amount) of fatty diet consumed than the dietary fat composition alone.  相似文献   
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Objective : To gather information from paediatricians concerning their attitudes to early intervention services for young children with developmental disabilities and to study their referral practices.
Methodology : Two hundred and ninety-five Australian paediatricians completed a postal questionnaire.
Results : Paediatricians presented a positive view of early intervention, particularly for its beneficial impact on families, and perceived the quality of services to be comprehensive or adequate. There were few differences between States, or between country or metropolitan areas. Most paediatricians make prompt referrals to early intervention services when a child has an established disability. Referral is much less likely with suspected delay.
Conclusions : Paediatricians are aware of the benefits of early intervention but additional information concerning the role of these services and their significant impact on families and children should be provided.  相似文献   
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Typhlitis presenting as toxic cecitis   总被引:2,自引:0,他引:2  
Cronin  TG  Jr; Calandra  JD; Del Fava  RL 《Radiology》1981,138(1):29
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