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101.
A comparison is given of energy loss results obtained for the L and K edges of aluminium as a function of specimen thickness, crystallographic orientation and collection angle. It is demonstrated that as the thickness is increased post-loss elastic scattering is generally important in reducing the fraction of electrons collected. The implications for the quantification of EELS data are discussed while a comparison of the Fe/C ratio in cementite demonstrates the improved consistency which can be obtained when comparing K and L losses at lower energy separation than are the losses for aluminium.  相似文献   
102.
103.
Using serial metabolic balance techniques, the absorption and retention of calcium and the absorption of fat have beem measured over the first 30 to 70 days of life in 11 preterm and 2 full-term light-for-dates infants. They were fed either full-cream cow's milk, half-skimmed cow's milk, the proprietary filled milk S.M.A., or breast milk. The values for calcium intake, absorption and retention were compared with the rate of accumulation of calcium by the fetus in utero, which was calculated from published data on the chemical composition of fetal bodies. Infants fed breast milk had an absolute dietary deficiency of calcium. Those fed other milks ingested sufficient but they did not absorb enough. Though calcium absorption increased with increasing postnatal age, intrauterine rates of calcium retention were never achieved on any of the milks. The average retention of calcium by preterm infants as a percentage of intrauterine accumulation was, for cow's milk 38%, for S.M.A. 27%, and for breast milk 17%. The full-term light-for- dates infants absorbed and retained more calcium than the preterm infants; it was on average 52% of the amount accumulated by the human fetus for an equivalent weight gain. The average absorption of fat by preterm infants was, from the cow's milk preparations 55%, from S.M.A. 61%, and from breast milk 84%. The light-for-dates infants absorbed on average 87% of the breast milk fat. There was no evidence that the amount of calcium absorbed was materially influenced by fat malabsorption. The principal determinants of the amount of calcium absorbed were the length of gestation and postnatal age of the infant.  相似文献   
104.
Clinical pathologies with unusually high morbidities in alcoholic populations were analyzed to determine their capacity to diagnose alcoholism. On the basis of five systemic variables it was possible to diagnose correctly nearly 75% of alcoholic and matched control subjects.  相似文献   
105.
In this review, the clinical reality, the statistical risk, and the frequency of thromboembolism in pill users are evaluated, 6 cases described, and premonitory signs, treatment, and etiology are discussed. Clinically these thromboembolisms appear in unlikely subjects and unusual bodily locations such as the mesenteric veins, without warning. The risks are 8-11 times higher for pulmonary thrombosis, 3-6 times higher for myocardial infarction, based on previously used higher dosed pills. The frequency is about .5-1/1000, or 500-1000/year in France. Some of the cases described used pills with less than .05 mg estrogen, some were heavy smokers, 1 woman died, 1 had a lower extremity amputation, and 1 woman had demonstrated IgG lamda antibodies against ethinyl estradiol. Premonitory signs are rare, and unsually ignored. The immediate action is to stop the pill and start anticoagulants. The cause of these disorders is not known in detail, but is presumed to be estrogens, therefore, low-dose pills, i.e., those with .05 or .03 mg ethinyl estradiol, should be used if possible. Other risk factors are surgery, age, immobilization, history of vein disorders, smoking, hyperlipidemia, hypertension, especially since the pill potentiates hypertension, hyperlipidemia, and hypercoagulation. Some mechanisms proposed are hyperlipidemia, disturbed blood coagulation factors, decreased fibrinolysis, alterations in the blood vessel endothelium and immunity against the estrogen in the pill.  相似文献   
106.
In recent years, prolonged wet weather during the harvest season resulted in excessive field- and storagedamaged soybeans, particularly in the Southeast. As the severity of the damage increased, analysis of the oil extracted from these beans showed a corresponding increase in free fatty acids, Lovibond color, and content of oxidative deterioration products which absorb at 270 nm. In general, there was a substantial decrease in total oil content and an almost complete deterioration of phospholipids in severely damaged beans during storage. Initially, the oxidative stability of the oils decreased rapidly. After storage damage became severe, the stability increased substantially, possibly because of the formation of unidentified deterioration products which had high antioxidant properties. The study clearly showed that the processing of field- and storage-damaged soybeans would result in substantial refining losses to processors and that the finished oil would be of inferior quality. ARS, USDA  相似文献   
107.
108.
Larval Typhlotriton spelaeus collected from five caves in Pulaski Co., Missouri, were kept as larvae or induced to transform in darkness or continuous fluorescent illumination. Larvae maintained in darkness for 215 and 279 days had smaller eyes, smaller rod inner and outer segments, and fewer metaphase figures in the germinative zone of the neural retina than comparable larvae maintained in light (258 lux). Except for visual cell size, differences were small and for each characteristic exceptions were observed. One larva kept in light showed early retinal degeneration comparable to that in transformed adults to T. spelaeus. All larvae exhibited optomotor behavior both before and after the experiment. Among animals induced to transform by L-thyroxin and maintained in darkness 111 to 366 days, visual cell and pigment epithelium degeneration was more extensive and more frequent than in animals kept for the same length of time in light (237-298 lux). In darkness the frequency of animals with retinal degeneration increased between 111 and 366 days. In light some animals exhibited pigment epithelium reduction with normal visual cells, and others had free, pigmented cells in the subretinal space. These effects were not comparable to degeneration in darkness. Eyelids covered the eyes of only a few animals in both light and dark treatments. The extent of eyelid encroachment over the eye greater in darkness than in light. Most animals exhibited optomotor responses after experiments, but responses of animals kept in darkness were impaired in comparison to those of animals kept in light.  相似文献   
109.
Considers ethical questions raised by the psychotherapeutic treatment of a highly religious person to be specific instances of general issues in the conduct of psychotherapy. It is stressed that the therapist has a responsibility to insure that the consent of the client is obtained under conditions of full information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
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