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941.
Hybrid sputtering and the conventional dc-template sputtering methods were used to deposit highly crystallinea-axis films. The oxygen contents and disorder of the films were measured by the resonant Rutherford backscattering. The oxygen content of the films deposited by the hybrid sputtering depend on the deposition temperature. Films deposited at a low temperature have low oxygen content. The poor superconducting properties of these films may be due to the oxygen deficiency. The stoichiometry of the films deposited by the dc-template sputtering method was found to depend on the microstructure of the template. The disorder at the Ba and O sublattices of these highly crystallinea-axis films are uncorrelated. 相似文献
942.
The effects of intraoral infusions of corn oil and the polysaccharide Polycose on behavioral reactions to pain and to social isolation were studied in 10-day-old albino rat pups. Both substances significantly increased paw-lift latencies (a measure of pain response) and reduced the number of ultrasonic vocalizations (a measure of isolation distress). Moreover, elevated pain thresholds were normalized by naltrexone (0.25 mg/kg) pretreatment, and the quieting of vocalizations was abolished by pretreatment. These findings indicate an interaction between ingestion, pain, and distress systems in neonatal rats and suggest that fats and polysaccharides influence these systems via endogenous opioids. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
943.
944.
Lymphocytes migrate from blood into lymph nodes (LN) of rats specifically at segments of venules lined by high endothelium (HEV). We have previously shown that pretreatment of LN HEV cells with pro-inflammatory cytokines such as tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma), augments their adhesiveness for thoracic duct lymphocytes (TDL). Here we report that a mouse monoclonal antibody, 3C10, recognized tissue-specific endothelial determinants on rat LN HEV cells and blocked their adhesiveness for TDL and EL-4J cells transfected with rat L-selectin. In contrast, 3C10 antibody did not inhibit lymphocyte attachment to Peyer's patch (PP) frozen sections or cultured PP HEV cells. The antibody immunoprecipitated from LN HEV cells two proteins with apparent molecular weights of 90,000 and 50,000. The expression of 3C10 antigen on LN HEV cells was increased by incubation with TNF-alpha or IFN-gamma. Furthermore, pretreatment of cytokine-stimulated LN HEV cells with 3C10 antibody blocked TDL binding in a dose-dependent manner. In contrast, 3C10 antigen expression on LN HEV cells was significantly decreased following incubation of cells with transforming growth factor-beta 1 (TGF-beta 1). In addition, TGF-beta 1 also abrogated the adhesiveness of LN HEV cells stimulated with TNF-alpha, IFN-gamma or both cytokines. Together, these data suggest that endothelial determinants recognized by the 3C10 antibody are tissue-specific ligands for lymphocyte adhesion and cytokines such as TNF-alpha and TGF-beta differentially regulate their expression and function. 相似文献
945.
The baccalaureate and masters programs in architectural engineering at the University of Miami are described here. The Bachelor of Science in Architectural Engineering (BSAE) program contains required courses in all the specialty areas of architectural engineering (structures, construction, and environmental systems), as well as courses in architectural design. Students can pursue each of these subjects in more depth by the proper selection of electives. The BSAE program requires 132 semester credits and is nominally a four-year program. The Master of Science in Architectural Engineering (MSAE) was introduced in 1990, and the course content of this program provides for specialization in one of the key areas of architectural engineering, and is customized for each student. Students with nonengineering backgrounds are typically admitted to the MSAE program with deficiencies. 相似文献
946.
N Shimoyama M Shimoyama CE Inturrisi KJ Elliott 《Canadian Metallurgical Quarterly》1996,85(6):1357-1366
BACKGROUND: The development of tolerance complicates the use of morphine to manage persistent pain. N-methyl-D-aspartate receptor antagonists can attenuate or reverse morphine tolerance. The authors studied ketamine's ability to modulate morphine tolerance. METHOD: Tolerance was produced in mice given morphine subcutaneously and was assessed by a cumulative dose-response analysis using the tail-flick test. The ability of ketamine at 0.3, 3, or 10 mg/kg given subcutaneously before and after morphine to attenuate the development of tolerance was assessed. The ability of 10 mg/kg ketamine to reverse tolerance produced by the subcutaneous implantation of morphine pellets to mice was also assessed. Rats were made tolerant to intraspinal morphine and the effects of the coadministration of 12 micrograms intraspinal ketamine were assessed. RESULTS: Morphine given subcutaneously produced a fivefold increase in the median effective (ED50) dose of morphine, which was dose-dependently attenuated by subcutaneously administered ketamine. A tenfold increase in the morphine ED50 produced by morphine pellets was completely reversed by ketamine given subcutaneously. Intraspinal morphine produced a 46-fold increase in its ED50, which was almost completely attenuated by the coadministration of intraspinal ketamine. CONCLUSIONS: Systemically administered ketamine attenuates and reverses systemically induced morphine tolerance in mice, and intraspinal ketamine attenuates tolerance produced by intraspinal morphine in rats. 相似文献
947.
Rochat Philippe; Blass Elliott M.; Hoffmeyer Lisa B. 《Canadian Metallurgical Quarterly》1988,24(4):459
This research identifies a coordinative structure of action that integrates hand and mouth activities within hours after birth. Infants in the supine position received 7 presentations of 12% sucrose solution. Differences in hand–mouth coordination relative to preceding and succeeding epochs of nonsucrose presentation were striking: 32% of the sucrose period was spent by infants with hands inside the mouth or in contact with it, and 18%, for the same measures during periods of nonsucrose delivery. In addition the hand was brought to the mouth 50% more often during the sucrose period. These data provide evidence for oropharyngeal control over intergration of gross motor patterns of hand movement as they relate to the mouth. A possible functional significance of these findings is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
948.
Search processes in a hierarchical menu selection system were investigated in a study that varied the structure of the tree. A hierarchical data base was composed of 256 gift items grouped into different clusters and presented using menus. Depth of the tree was held constant while breadth varied with level. Five structures were explored with the following number of alternatives at each of four levels: constant (4 × 4 × 4 × 4), decreasing (8 × 8 × 2 × 2), increasing (2 × 2 × 8 × 8), concave (8 × 2 × 2 × 8), and convex (2 × 8 × 8 × 2). Subjects searched for either specifically named gifts (explicit targets) or gifts appropriate for a scenario situation (scenario targets). In general, explicit targets took less time to find and fewer frames to traverse than for scenario targets. For explicit targets, the increasing menu was slightly superior to the rest. Search time was about the same across the five tree structures for explicit targets, but differed greatly for scenario targets. The concave and increasing structures were faster than the constant structure and the convex and decreasing structures were slower. Similar results were found for the number of frames traversed. The patterns of search also differed greatly among the five structures in terms of the frequency of use of the 'previous' command and the 'top' command. The 'previous' command was used most frequently with the convex menu and least frequently with the concave menu. For scenario targets, the 'top' command was used most frequently with the decreasing menu and least frequently with the increasing menu. For explicit targets, the 'top' command was used most frequently with concave menu and least frequently with increasing menu. The pattern of search indicated that if subjects moved back up the tree they tended to move to a level with eight choices rather than two. Overall, it is concluded that the concave menu is superior when searching for scenario targets and the increasing menu is slightly superior when searching for explicit targets. A theory of menu uncertainty based on information theory is proposed which helps to account for some of the results. 相似文献
949.
Research on childhood family environments of mental health professionals suggests that therapists are often raised in dysfunctional families and experience significant psychological distress in adult life. This study examined the prevalence of childhood trauma, family dysfunction, and current psychological distress among female mental health professionals (N?=?340) and compared it with the prevalence among women working in other professions (N?=?2,623). Psychotherapists reported higher rates of physical abuse, sexual molestation, parental alcoholism, psychiatric hospitalization of a parent, death of a family member, and greater family dysfunction in their families of origin than did other professionals. As adults, psychotherapists experienced less anxiety, depression, dissociation, sleep disturbance, and impairment in interpersonal relationships than did women in professions other than mental health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
950.
Thomas R. Elliott 《Information Systems Management》1988,5(4):74-75
Computer vendors are tailoring their marketing efforts to address the specific needs of their customers. This column examines the impact of this precise way of marketing. 相似文献