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121.
122.
Used a multiple constituency framework to examine the correlates (antecedents) of organizational commitment among 124 mental health professionals (mean age 28 yrs). Ss completed a constituency endorsement measure and an organizational commitment questionnaire. Conflicts among multiple commitments and multiple commitments to several constituencies (3 internal and 1 external) were correlated with global organizational commitment. Results indicate that the perceived conflict between individual and managerial goal orientations was significantly associated with organizational commitment. In addition, only commitment to top management's goals was positively associated with commitment to the organization. It is suggested that commitments may develop over time and should therefore be studied longitudinally. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
The melting and crystallization of nylon 6/copper chloride system has been studied by differential scanning calorimetry. In light of the strong melting temperature depression, above the expected in a polymer–diluent mixture and the strong retardation of the crystallization rate, a high degree of binding, probably even complexing, between the salt and the polymer chain is discussed. 相似文献
124.
Arnon E. Munter E. Patel S. Roddick P. Willcock P. 《Communications, IEEE Transactions on》1982,30(9):2143-2149
The key to the successful emergence of the information society [1] is an access system that permits new and diverse communication services to flourish. A fundamental component of such a network is a digital end-to-end communication capability. This paper presents an approach to the design of a digital access system for application in both residential and business environments. Switch, customer premises, and distribution design concepts are presented, and the results of field and laboratory tests of a multichannel digital distribution system are described. 相似文献
125.
Cardiovascular diseases are the leading causes of death in the United States, with hypertension being amongst the most prevalent of the cardiovascular risk factors. Improvement of hypertension management has, in consequence, received much attention. Extensive pre- and post-marketing experience with the transdermal formulation of clonidine marketed in the USA in the mid-1980s has now been accumulated. Transdermal clonidine is effective as monotherapy in mild-moderate hypertension, and in combination with diuretics, calcium antagonists and ACE inhibitors in more resistant cases. It controls blood pressure throughout the 24-h circadian cycle. It is effective and generally well-tolerated in adolescents, the elderly, blacks, diabetics, and subjects with chronic renal insufficiency. It has been used perioperatively and for suppression of adrenergic symptoms in subjects withdrawing from addicting substances. In comparison with oral clonidine, transdermal clonidine reduces the incidence and severity of such symptomatic side-effects as dry mouth, drowsiness, and sexual dysfunction. Minor skin reactions occur at the site of application of the transdermal patch with moderate frequency. Adherence to transdermal clonidine therapy is high, and patients commonly prefer it to oral therapy. Transdermal administration of clonidine is a useful therapeutic advance in the long-term management of hypertension. 相似文献
126.
127.
To evaluate the clinical significance of eosinophilia in newborn infants, 261 admissions to the neonatal unit over a 12-month period were studied retrospectively; 33 babies with eosinophilia (> 1.0 x 10(9)/l) were studied. Clinical and laboratory data for the first month of life were compared, where available, between gestational age-matched pairs with and without eosinophilia. Of the 33 babies with eosinophilia, 23 were > 26 weeks' gestation and all had age-matched controls; 10 were < or = 26 weeks' gestation but had no appropriate gestational age-matched controls. Babies > 26 weeks' gestation with eosinophilia had a significantly higher number of septic episodes than controls: 20 of 23 versus 4 of 23. All 10 babies < or = 26 weeks' gestation with eosinophilia developed sepsis. Infections with gram-negative organisms and necrotizing enterocolitis occurred only in babies who developed eosinophilia. In 5 babies no cause for the eosinophilia was found. In conclusion, eosinophilia in the newborn is usually explainable and is most often associated with infection. 相似文献
128.
129.
Arnon S. Kopeika N.S. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1997,85(10):1646-1661
A number of serious consortiums develop satellite communication networks. The objective of these communication projects is to service personal communication users almost everywhere on Earth. The intersatellite links in those projects use microwave radiation as the carrier. Free-space optical communication between satellites networked together can make possible high-speed communication between different places on Earth. Some advantages of an optical communication system over a microwave communication system in free space are: (1) smaller size and weight, (2) less transmitter power, (3) larger bandwidth, and (4) higher immunity to interference. The pointing from one satellite to another is a complicated problem due to the large distance between the satellite, the narrow beam divergence angle, and vibration of the pointing system. Such vibration of the transmitted beam in the receiver plane decreases the average received signal, which increases the bit error rate. We review: (1) the present status of satellite networks, (2) developing efforts of optical satellite communication around the world, (3) performance results of vibration effects on different kinds of optical communication satellite networks, and (4) seven approaches to overcome the problems caused by transmitter pointing vibration 相似文献
130.
R Arnon 《Canadian Metallurgical Quarterly》1996,50(1-2):1-15
The aim of the review is to summarize the present knowledge on determinants of transfer of low density lipoprotein (LDL) into the arterial wall, particularly in relation to the risk of development of atherosclerosis. The flux of LDL into the arterial wall (in moles of LDL per surface area per unit of time) has two major determinants, i.e. the LDL concentration in plasma and the arterial wall permeability. LDL enters the arterial wall as intact particles by vesicular ferrying through endothelial cells and/or by passive sieving through pores in or between endothelial cells. Estimates in vivo of the LDL permeability of a normal arterial wall vary between 5 and 100 nl/cm2/h. In laboratory animals, the regional variation in the arterial wall permeability predicts the pattern of subsequent dietary induced atherosclerosis. Moreover, mechanical or immunological injury of the arterial wall increases the LDL permeability and is accompanied by accelerated development of experimental atherosclerosis. This supports the idea that an increased permeability to LDL, like an increased plasma LDL concentration, increases the risk of atherosclerosis. Hypertension, smoking, genetic predisposition, atherosclerosis, and a small size of LDL may all increase the arterial wall permeability to LDL and in this way increase the risk of accelerated development of atherosclerosis. The hypothesis that atherosclerosis risk can be reduced by improving the barrier function of the arterial wall towards the entry of LDL remains to be investigated; agents which directly modulate the LDL permeability of the arterial wall in vivo await identification. 相似文献