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1.
Psychologists' activities and accomplishments are examined to reveal patterns associated with employment setting and field of specialization. Results based on a survey of 7,373 psychologists imply that brief self-report checklists of activities and accomplishments in five areas (scholarly contributions, contributions to local community, contributions to organized psychology, contributions in administration and consulting, and practitioner activities) have reliabilities ranging from .64 to .78 and have a median intercorrelation of only .33. Patterns of accomplishment are strongly associated with employment setting and with subfield. Although psychologists employed in university or 4-year college departments score high on scholarly contributions, they make fewer contributions in other areas than do psychologists employed elsewhere. Other results are interpreted as implying that practitioner activities make a greater contribution to income than do activities and accomplishments in other areas. Implications for organized psychology, career development, and understanding the diversity of psychological work are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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PURPOSE: To measure the compressive forces of the haptics of 28 intraocular lens (IOL) models for different modes of compression and compare the results of two types of measurements. SETTING: Department of Ophthalmology, Central Hospital of Central Finland, Jyv?skyl?, Finland. METHODS: The haptics of 28 types of IOLs were compressed to a diameter of 9.0 mm between curved anvils. The compression forces in the plane of compression (i.e., in the plane of the optics) were measured at 0.5 mm intervals. During compression, the optics and the haptics were free to rotate with respect to the anvils. The results were compared with those of earlier measurements in which the optics were held fixed during compression. Perpendicular forces were measured at 0.4 mm intervals. RESULTS: The measured forces in the plane of the optics varied between 114 and 659 mg at a diameter of 10.0 mm and 192 and 1047 mg at a diameter of 9.0 mm. When compressed to 10.0 mm in diameter, the forces were 1 to 75% lower than when lens rotation was not possible. The forces perpendicular to the optic varied between 0 and 96 mg at a 10.0 mm diameter and correlated with the forces in the plane of the optic. CONCLUSION: The compression forces of the lens haptics were generally lower when the lenses were allowed to rotate during compression. The orders of stiffness of the haptics in these two measurements were similar. The perpendicular forces were generally small and correlated significantly with the forces measured in the plane of the optic.  相似文献   

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Aminoglycoside resistance patterns of 147 Serratia marcescens strains of clinical origin were studied. All strains analysed belonged to three different bacterial populations. The periods of study and the institutions the strains were isolated from correlated significantly with the resistance patterns shown by the strains. The most frequent resistance patterns found were the following: ACC (6')-I at the Hospital Infantil de México (Children's Hospital of México), and ANT (2') + AAC(6')-I at the Instituto Nacional de Pediatría (INPed or National Institute of Pediatrics) in Mexico City. Furthermore, the isolation frequency of aminoglycoside-sensitive strains decreased remarkably at the INPed over a 12-year period. These results suggest that there has been a selection of Serratia marcescens strains that are very resistant to aminoglycosides.  相似文献   

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The pbp4 gene of a Staphylococcus aureus strain selected stepwise in vitro for growth on increasing concentrations of penicillin and of its susceptible parent strain showed overall identity except in the promoter region. In the mutant a deletion upstream of the pbp4 structural gene removed 90 nucleotides (nt) that were framed by a 12 nt inverted repeat. This deletion occurred in step 4 of the in vitro selection procedure and was paralleled by a significant increase in the penicillin-binding protein 4 (PBP4) production. The in vitro step selected mutant showed a remarkable increase in the cross-linking of the peptidoglycan compared to its parent. This was linked to morphological changes in the appearance of the cells, which were surrounded by a very thick and fuzzy cell wall.  相似文献   

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Several theories have been proposed to explain the evolution of species differences in brain size, but no consensus has emerged. One unresolved question is whether brain size differences are a result of neural specializations or of biological constraints affecting the whole brain. Here I show that, among primates, brain size variation is associated with visual specialization. Primates with large brains for their body size have relatively expanded visual brain areas, including the primary visual cortex and lateral geniculate nucleus. Within the visual system, it is, in particular, one functionally specialized pathway upon which selection has acted: evolutionary changes in the number of neurons in parvocellular, but not magnocellular, layers of the lateral geniculate nucleus are correlated with changes in both brain size and ecological variables (diet and social group size). Given the known functions of the parvocellular pathway, these results suggest that the relatively large brains of frugivorous species are products of selection on the ability to perceive and select fruits using specific visual cues such as colour. The separate correlation between group size and visual brain evolution, on the other hand, may indicate the visual basis of social information processing in the primate brain.  相似文献   

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Sepsis occurs frequently in the pediatric intensive care unit and is a significant cause of morbidity and mortality. Multiple organ systems are adversely affected by sepsis. Approximately 70% of adult patients with sepsis have peripheral nervous system dysfunction on electrophysiologic studies, of whom 30% are symptomatic. Neuromuscular dysfunction in children with sepsis is increasingly reported; however, the incidence remains undefined. Flaccid quadriplegia with the inability to wean from ventilatory support despite full cardiopulmonary recovery is the typical presentation. However, lesser degrees of weakness may be demonstrated with careful evaluation. Electrophysiologic studies often demonstrate the presence of axonal polyneuropathies, abnormalities of neuromuscular transmission, or acute myopathies. Identifiable neuromuscular syndromes in children with sepsis include critical illness polyneuropathy, pure motor polyneuropathy, thick-filament myopathy, and necrotizing myopathy. The common underlying pathogenic process in these syndromes appears to be sepsis, which may be accentuated by the administration of steroids or neuromuscular blocking agents. Recovery in strength usually occurs over a period of weeks to months.  相似文献   

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Hemispheric specialization and the growth of human understanding.   总被引:1,自引:0,他引:1  
Connectionistic notions of hemispheric specialization and use are considered incompatible with the network organization of the human brain, and alternative concepts are suggested. The functionally specialized areas of the cerebrum are diffusely interconnected; differences in degree of connection define a "functional cerebral space" within which similar activities are represented in adjacent loci but dissimilar activities in loci that are further apart. This explains why one can easily do dissimilar things at the same time but similar things only one after another. Bilaterally represented processes relate the organism to the periphery. Lateralized processes are deployed in focal attention, the specifics being extracted by the left hemisphere and related to each other in space by the right hemisphere. These contributions to mental life are complementary modes of processing. They can be dissociated only when mentally represented. Item and relational aspects of a problem can be separately abstracted, elaborated, and communicated; there has been relatively independent growth of understanding in these 2 domains. (61 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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In children with immune thrombocytopenic purpura (ITP), bone marrow lymphocytes can express the common acute lymphoblastic leukemia antigen (CALLA) pattern with no evidence of leukemia or lymphoma. Bone marrow lymphocytes from 23 children and 20 adults affected with ITP were studied to determine the incidence and the clinical impact of lymphocytes with the immature B-cell phenotype and CD34+ cell expression. In this investigation we identified a group consisting of 52% of the children who showed the immature B phenotype, while the remaining 48%, similarly to adult ITP displayed an increase of T-cell antigens. CD34 was positive in 53% of children, but it was present in only half of the patients with the immature B phenotype and it was always absent in adults. IgH genes disclosed a germline configuration in all six patients in the immature B phenotype group. No difference was found in the two groups of children in terms of age, presentation of the disease or final outcome. Finally, no patient in either children's group has developed an acute lymphoproliferative disorder.  相似文献   

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Synaptic differentiation is triggered by signals from the ingrowing axon and is shaped by information exchange between the presynaptic and postsynaptic cells. The central role of agrin in this process, and the identity of the signaling component of its receptor, have now been established.  相似文献   

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Silica deposition is a fundamental process in sponges. Most sponges in the Classes Demospongiae and Hexactinellida secrete siliceous elements, which can subsequently fuse, interlock with each other, or form three-dimensional structures connected by spongin. The resulting skeletal frameworks allow sponges to grow upwards and facilitate water exchange with minimal metabolic cost. Several studies on sponge skeletogenesis have been published. We are beginning to understand the mechanisms of spicule secretion and the role of spicules and skeletal frameworks in the biology, ecology, and evolution of sponges. Molecular techniques and ecological experiments have demonstrated the genetic control of the process and the contribution of environmental factors to the expression of a sponge spicule, respectively. However, other classic topics such as the role of membranes in silicon transport or whether spicules are formed in situ or secreted anywhere in the sponge mesohyl and then transported to the skeletal framework require further investigation. We review the process of silica deposition in sponges at the molecular and cellular levels, as well as the biological and ecological functions of spicules and skeletons. The genetic control of spicule shapes makes them useful in the reconstruction of sponge phylogeny, although recent experiments have demonstrated the influence of environmental factors in modulating spicule size, shape, and the presence or absence of one or more spicule types. The implications of such variations in sponge taxonomy may be important. Besides supporting sponge cells, spicules can help larvae stay buoyant while in the plankton or reach the bottom at settlement, enhance reproduction success, or catch prey. Conversely, the role of spicules and skeletons in deterring predation has not been demonstrated. Knowledge of several aspects is still based on a single or a few species and extrapolations should be made only with caution. With the advent of new molecular techniques, new lines of research are presently open and active in this field.  相似文献   

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Argues that W. Thorngate's (see record 1991-03036-001) proposals to alter the academic reward system to reduce production of psychological literature are based on a rationalist-constructivist conception of the social orders of science and academia. A radical rethinking of psychologists' views on the science of psychology will be necessary for avoiding fragmentation of the discipline. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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A concise practical, large scale-adaptable six-step sequence has been developed for the transformation of diacetone-glucose into 4,6-di-O-benzoyl-3-O-benzyl-alpha-D-arabino-hexopyranos-2-ulosy l bromide (7), a most useful indirect beta-D-mannosyl donor as its blocking group pattern allows the construction of biologically relevant beta-D-mannosides branched at O-3 and O-6. The broad utility of this new ulosyl bromide 7 resides in its high anomeric reactivity, and in the ease and uniformity with which beta-stereocontrol can be achieved over both, glycosidations and carbonyl reduction of the beta-ulosides formed: Koenigs-Knorr conditions exclusively provide beta-glycosiduloses, hydride reduction of their carbonyl functions proceeds with high stereoselectivities (> 20:1) in favor of the beta-D-mannosides. These preparatively auspicious properties are materialized in an efficient, straightforward synthesis of alpha-D-Manp-(1-->6)-[alpha-D-Manp-(1-->3)]-beta-D-Manp++ +-(1-->O)-Octyl, the 3,6-O-branched core-mannotrioside carrying an octyl spacer instead of the chitobiosyl unit.  相似文献   

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Reviews research on the hemispheric asymmetry model of relative ear advantages in the processing of auditory stimuli. Physiological studies of activation of the hemispheres in humans support left-hemisphere speech-processing specialization and contralateral sound field dominance. Electrophysiological studies in animals, effects of commissurotomy, hemispherectomy, and unilateral temporal lobe lesions on dichotic performance in humans, as well as stimulus dominance effects in intact Ss indicate that the assumption of ipsilateral sensory pathway suppression during competitive stimulation is unwarranted. Dichotic presentation is not necessary to produce a right-ear advantage (REA), and selective attention to one or the other ear frequently tends to alter the magnitude of the REA. A modified structural model that incorporates the effects of directed attention is proposed. (3? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The two hemispheres of the brain often perform complementary computations and make unique contributions to task performance. This study examines the interaction of linguistic (left hemisphere) and prosodic (right hemisphere) information in speech processing. An individual differences approach is used in which interference between linguistic and prosodic processes in a Stroop-like task is compared between individuals who process the two dimensions in opposite hemispheres (complementary specialization) vs. those who process both dimensions in the same hemisphere (noncomplementary specialization). Complementarity was not related to interference in any way. This finding is consistent with the hypothesis of Chiarello and Maxfield (1996) that interference is equivalent between and within hemispheres when it arises in a response selection stage.  相似文献   

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Practicing psychologists face numerous questions regarding specialization, reflecting the dramatic changes occurring in the last half of the 20th century. Is the specialization trend in professional psychology practice and training out of step with marketplace realities? Should specialty training and practice be guided and controlled, and if so, by whom? In response to the interplay of various forces and in a spontaneous and unguarded fashion, specialization has evolved in the form of a two-tiered model, consisting of general practice specialties and delimited specialties. The model better reflects existing distinctions in roles, methods, and settings for education and training than does the systematic differentiation of specialist functions or practice competencies. Were the discipline to implement an orderly sequence of steps to develop a coherent system for specialization in psychology, it would facilitate its future growth and development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Acute renal failure developed in nine of 78 patients who were subjected to hepatic artery ligation for nonresectable and extensive malignant tumor of the liver. Of those nine, six had hepatomas, one cholangiocarcinoma, one metastatic islet-cell carcinoma and one metastatic melanoma. Preoperative renal function as reflected in blood-urea-nitrogen and serum creatinine values was within normal limits. There were marked elevations of serum glutamic-oxalacetic transaminase and lactic dehydrogenase levels after hepatic artery ligation, an indication of massive ischemic injury of the tumor and the liver. A diagnosis of acute renal failure was established within 14 to 70 hours after hepatic artery ligation. In five patients, oliguric renal failure developed, and in four, high urinary output renal failure. In only three patients did systemic hypotension and hypovolemia precede acute renal failure. Seven of the nine patients died. Postmortem examination was done in five patients, and in only two was there evidence of renal tubular necrosis. The factors contributing to acute renal failure appear to be extensive involvement of the liver by tumor, presence of ascites and jaundice, occlusion of the portal vein and hyperuricemia. The presence of any one of the foregoing contraindicates the procedure.  相似文献   

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