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101.
BS Reddy A Mastromarino C Gustafson M Lipkin EL Wynder 《Canadian Metallurgical Quarterly》1976,38(4):1694-1698
Fecal neutral steroids and bile acids were measured in patients with familial polyposis, family controls who are immediate relatives of patients, and controls other than relatives. All subjects were consuming a mixed Western diet at the time of collection of stool specimens. Although the total fecal neutral sterol concentrations were not different between the groups, the patients with familial polyposis excreted a high amount of cholesterol and low levels of coprostanol and coprostanone compared with other groups. Patients with familial polyposis excreted levels of total bile acids in their feces comparable to those excreted by controls; lithocholic acid excretion was decreased in patients with familial polyposis. These findings suggest that analysis of stools for cholesterol and its metabolites be useful in screening the siblings of polyposis families for latent disease. 相似文献
102.
Malignant melanoma of the mucous membranes is rare and has a very poor prognosis. When localized in the nose, the tumor becomes apparent late in the course of the disease with nasal obstruction and epistaxis. Distant metastases are uncommon, but any organ of the body can be involved. A case of a malignant melanoma of the nasal mucosa with metastasis to the small intestine is presented, and the natural history of the metastatic disease is discussed. 相似文献
103.
Analysis of measurements from the tali of 21 individual fossil primates from Africa shows that the specimens fall into five clearly defined groups. Accordingly, these specimens have been included as groups along with extant species in a subsequent canonical analysis thus allowing the fossils to play their part in the determination of the canonical separations. The results of this procedure show that the five fossil groups lie in a part of the canonical space not occupied by any extant African primate. Their positions are between the envelope of Asiatic apes (Hylobates and Pongo) and the envelope of African forms near the edge which contains Pan and Papio. One fossil group is so similar to Hylobates that its talus may have functioned in locomotion in a parallel manner. Others lie near to Pongo in directions proceeding towards Pan and Papio and it is possible that this similarity may indicate remnants of morphological adaptation for climbing in these fossils. At the same time, however, individual specimens are closer to one or another of the extant groups and this considerable spread suggests that the locomotor adaptations as evidenced by talar morphology, of the primate fauna in Africa, may have been very different from those of the present day. This would not the inconsistent with the different habitats, floras and non-primate faunas that may have characterized the East African scene at these earlier times. Particular fossils from Olduvai and Kromdraai that are supposed to be australopithecine and therefore bipeds, are confirmed (Oxnard, '72; Lisowski et al., '74) as being totally different from man in their talar morphology and essentially rather similar to the majority of the other fossil tali examined. 相似文献
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Moraes JE Quina FH Nascimento CA Silva DN Chiavone-Filho O 《Environmental science & technology》2004,38(4):1183-1187
The application of the photo-Fenton process to the treatment of saline wastewater contaminated with hydrocarbons is investigated. Aqueous saline solutions containing raw gasoline were used as a model oil-field-produced water. The dependence on concentrations of the following reagents has been appropriately evaluated: hydrogen peroxide (100-200 mM), iron ions (0.5-1 mM), and sodium chloride (200-2000 ppm). The reactions were monitored by measurement of the absorption spectra and total organic carbon (TOC). Experimental results demonstrate that the photo-Fenton process is feasible for the treatment of wastewaters containing hydrocarbons, even in the presence of high concentrations of salt. The effect of the salt in this process is described through a series of reactions. A simple feedforward neural network model was found to correlate well the observed data for the degradation process. 相似文献
107.
Recently promulgated federal regulations mandate the provision of an emergency, self-contained, oxygen-supplying breathing device (self-contained self-rescuer, SCSR) to all underground coalminers. In order to assist in defining the potential limitations of this new device, we measured the responses of ten healthy coal mine inspectors to submaximal steady-state treadmill exercise with and without the SCSR. During the last minute of exercise, blood oxygen saturation averaged 98.3% and mouth pressure swing 15.6 cm H2O with the device, compared to 94.8% and 10.4 cm H2O without it. Mean respiratory rates were decreased to 25/min with the SCSR from 28/min without it. Blood pressure, core temperature and heart rate were unaffected. We conclude that in healthy individuals on submaximal exercise there is little evidence of a significant adverse effect of the new device. 相似文献
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Reversal of pretreatment hypotension and control of hemorrhage in trauma patients by a simple device
JM Civetta ST Nussenfeld EL Nagel BH Kaplan TR Rowe F Pettijohn 《Canadian Metallurgical Quarterly》1977,43(1):20-29
The injection of a suspension of Walker 256 carcinoma cells into the carotid artery of rats produced a model of hematogenously spread cerebral metastases. Most animals died from massive extracerebral tumors of the head and jaw; brain tumors were present in only one-quarter. External carotid artery ligation prior to tumor inoculation did not increase the incidence of fatal brain tumor. When cyclophosphamide, 15 mg/kg, was injected as a single dose on the fourteenth day after tumor inoculation, most of the extracerebral tumor disappeared. Fifty percent of the animals so treated were cured of tumor, but 90% of the remainder died of large intracerebral tumors. Severe cytopathic changes resulting from cyclophosphamide were present in extracerebral or choroid plexus tumors but were mild or nonexistent in intracerebral tumors. These selective effects of cyclophosphamide suggest that water-soluble agents are less effective against tumor in the brain than against extracerebral tumors despite the fact that metastatic tumor breaks down the blood-brain barrier. 相似文献
110.