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The uptake of free and liposome-entrapped 125I-labelled poly(vinylpyrrolidone) was measured in an intestinal sac preparation from adult rats. An an equal concentration of 125I-labelled poly(vinylpyrrolidone), the rate of uptake of the liposome-entrapped material was four times that of the free macromolecule.  相似文献   
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Pregnant hamsters were administered (SC) prostaglandin or vehicle on the morning of the 4th day of pregnancy. Serum progesterone was significantly depressed (p<.01) at 0.5, 2, and 6 hours after treatment with 100 μg PGF. Serum progesterone levels were unchanged 2 hours and 6 hours after treatment with 100 μg PGF and 2 hours after treatment with 1 mg PGF. Progesterone levels were depressed to less than 1 ng/ml 6 hours after treatment with 1 mg PGF. The specific uptake of 3H-PGF in whole hamster corpora lutea was significantly depressed 2 hours and 6 hours following 100 μg PGF treatment. A 15% depression in specific uptake occurred 0.5 hour post-treatment. Treatment with 100 μg PGF resulted in no change. Administration of 1 mg PGF resulted in depressed 3H-PGF uptake at both 2 and 6 hours post-treatment.Prostacyclin (PGI2) treatment resulted in no change in either 3H-PGF specific uptake or serum progesterone 2 hours after 100 μg treatment SC. These parameters were both reduced approximately 30% 6 hours post-treatment. Treatment with 6-keto-PGF resulted in a complete lack of measurable 3H-PGF uptake and serum progesterone levels less than 1 ng/ml at both 2 and 6 hours after treatment with 1 mg SC.  相似文献   
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This study was presented in part at the annual meeting of the Wilderness Medical Society at Aspen, Colorado, in August 1986 and at “Mountain Medicine 1987,” Leavenworth, Washington, in November 1987.We questioned 220 injured rock climbers or their partners seen consecutively at the Yosemite (California) Medical Clinic over 3 ½ years regarding details of their accidents. Injury type and location were extracted from medical records and severity quantified. The National Park Service rescued 27% of the climbers. Injured climbers were characteristically male (88%) and experienced (mean 5.9 years) and typically fell while leading climbs (66%). Among 451 injuries, 50% were to the skin or subcutaneous tissues, while 28% involved the lower extremity and were predominantly fractures. In terms of each climber''s most severe injury (n = 220), 45% involved the lower extremities (30% from the ankle alone). Head injury or hypothermia caused 12 of 13 fatalities, showing the lowest case-fatality rate reported to date among injured climbers (6%). Rescue personnel successfully managed airways in victims of head injuries, anticipated and treated complications of hypothermia, and stabilized fractures. Victims requiring immediate extensive surgical intervention or blood transfusion usually died before rescue could be effected.  相似文献   
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