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31.
The growth structure of MgF2 and NdF3 films grown on polished CaF2(111) substrates deposited by molecular beam deposition has been investigated using transmission electron microscopy (TEM) of microfractographical and surface replications as well as cross-sectional TEM, atomic force microscopy, packing density, and absorption measurements. It has been shown that by taking advantage of ultrahigh vacuum environments and a special stratification property of MgF2 and NdF3 films, the preparation of nanocrystalline films of high packing density and low optical absorption is possible at a substrate temperature of 425 K.  相似文献   
32.
In tests of direct-compression hydrochlorothiazide tablets prepared with either of two varieties of microcrystalline cellulose (Avicel PH 101 and Avicel PH 102), PH 102 tablets had better mechanical properties (owing to lower compressibility of mixtures and greater Interparticle bonding), while PH 101 tablets released the active principle faster. These differences are related to observed differences In tablet micropore structure.  相似文献   
33.
Psychosomatic symptoms among children are believed to be commonplace. In this investigation by questionnaire, 47% of 1333 schoolchildren reported one or several symptoms, such as recurrent abdominal pain, headache, chest pains, loss of appetite and disturbances in bowel function. Coexistence of such symptoms was considerable and if a child had one of these, the probability that it would have one or more other symptoms was significantly increased. This correlation may strengthen both the suspicion that these symptoms are often psychosomatic and the idea that they have common CNS origin. There were appreciable differences in the frequency of the symptoms, between children at the more socially stable schools and schools with social problems. In the latter, the frequencies of symptoms differed between Swedish and immigrant children, which was not the case in the more socially stable schools.  相似文献   
34.
This paper reviews current trends in shortcreting, primarily based on the Status Report of a Working Group of the International Tunneling Association and the most recent U.S. Engineering Foundation conference on the theme (held in Uppsala, Sweden, in 1990). Of special interest is the increasing use of fibre reinforcement, which implies increased safety and substantial cost savings. The need for scientific collaboration and exchange of ideas between concrete and rock mechanics specialists is emphasized as a tool for a better understanding of the support behaviour of shotcrete linings.  相似文献   
35.
We previously isolated a mutant cell that is the only mammalian cell reported to have a persistently low level of UDP-glucose. In this work we obtained a spontaneous revertant whose UDP-glucose level lies between those found in the wild type and the mutant cell. The activity of UDP-glucose pyrophosphorylase (UDPG:PP), the enzyme that catalyzes the formation of UDP-glucose, was in the mutant 4% and in the revertant 56% of the activity found in the wild type cell. Sequence analysis of UDPG: PP cDNAs from the mutant cell showed one missense mutation, which changes amino acid residue 115 from glycine to aspartic acid. The substituted glycine is located within the largest stretch of strictly conserved residues among eukaryotic UDPG:PPs. The analysis of the cDNAs from the revertant cell indicated the presence of an equimolar mixture of the wild type and the mutated mRNAs, suggesting that the mutation has reverted in only one of the alleles. In summary, we demonstrate that the G115D substitution in the Chinese hamster UDPG:PP dramatically impairs its enzymatic activity, thereby causing cellular UDP-glucose deficiency.  相似文献   
36.
We have assessed the antimicrobial, vapor-phase activity of the following natural essential oils (EOs) when used in paraffin-based “active coatings” for paper packaging materials intended to come into contact with foods: clove (Sygzium aromaticum), cinnamon (Cinnamomum zeylanicum), and oregano (Origanum vulgare) EOs, and cinnamaldehyde-enriched cinnamon EO. To our knowledge, this is the first time that such an approach has been presented for consideration by the scientific community.  相似文献   
37.
Adjuvant-induced arthritis is an animal model of chronic inflammatory disease widely used in anti-inflammatory and immunosuppressive drugs testing. When the development and the inhibition of the induced arthritis are measured by the injected paw oedema, it is difficult to delineate the immunological contribution from the persistent non-specific primary section. To study the influence of volume and composition of the injected adjuvant upon the primary non-specific inflammation, we devised a 3X4 factorial experiment on a strain of inbred rats with a low susceptibility to adjuvant-induced arthritis. The injection of mineral oil alone produces a persistent oedema. The injection of mycobacteriae in suspension in saline induces a rapid inflammatory response followed by a fast decrease of the oedema. When complete adjuvant is used, there is always a very strong interaction between the effects of the two components of the adjuvant, i.e. the measured oedemas are much greater than the calculated values, For a given injected volume, the inflammation is maximum when the concentration of mycobacteriae is 2.5 mg/ml. All the rats injected with complete adjuvant present a transient oedema of the non-injected hind paw. This oedema is very small and proportional to the amount of mycobacteria injected.  相似文献   
38.
Gerhard Mathé 《NTM》1994,2(1):13-26
This paper on the occasion of the 500th birthday of the great Saxon humanistic scholar Georgius Agricola deals with his contributions to geology in the narrow sense. These, contrary to his voluminous works on mining, metallurgy and mineralogy (De re metallica and De natura fossilium, resp.) are parts of the booksDe ortu et causis subterraneorum andDe natura eorum, quae effluunt ex terra. In those we find statements on the causes of earthquakes, on volcanos and the subterranean fire as well as the effects of the running water in mountain-building. Agricola's ideas on geological time and his statements on dynamics of the Earth's crust are remarkable.  相似文献   
39.
40.
Discusses the theoretical and clinical applications of the postmodern paradigm of social constructionism as a basis for counseling culturally different clients. Such applications avoid the trap of perpetuating the status-quo when working with minority and marginalized clientele. The main points of multiculturalism and social constructionism are summarized, and issues of mutual concern to both perspectives are examined. Applications to psychotherapy are explored, and the challenges of applying the social constructionist approach to culturally competent counseling are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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