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101.
102.
Trimellitic anhydride Toxicity. A cause of acute multisystem failure   总被引:1,自引:0,他引:1  
A person exposed to trimellitic anhydride (TMA) an epoxy resin widely used in industry, experienced respiratory failure, anemia, and gastrointestinal bleeding. A lung biopsy specimen demonstrated intra-alveolar hemorrhage and damage to alveolar lining cells. The patient and six co-workers were examined. Results indicated the presence of hemolytic antibodies directed against TMA-haptenized erythrocytes, IgG, IgA, and IgM antibodies directed against TMA-erythrocyte complexes, and antibodies against TMA-human serum albumin. Antibody levels in the patient were greater than in the co-workers. The elevated antibody levels demonstrate the antigenic potential of TMA. However, the cause of the pulmonary and hematologic damage remains uncertain and may represent either immunologic or direct toxic effects of TMA. In patients with multisystem failure of this nature, occupational hazards should be added to the differential diagnosis.  相似文献   
103.
A ninety-six element scanning array, which operates over an octave bandwidth, has been built and tested. The array beam is steered with digital latching ferrite phase shifters, which have low insertion loss and essentially constant phase shift over considerably more than an octave. A reasonable match has been achieved through the use of dielectric transformers at both the input and radiating apertures. The array performs properly over nearly an octave bandwidth for scan angles up to 60°, but at the upper end of the frequency band, the thick dielectric transformers caused a surface wave-type phenomenon and a subsequent loss of the main beam. An examination of the occurrence of `lost beams' at scan angles of 60° showed that these effects could be predicted from simulator measurements performed at higher frequencies and smaller scan angles  相似文献   
104.
Reports on studies emphasizing a neuropsychological approach to the investigation of learning disabilities in children. Areas reviewed include the level of performance approach, attentional deficits, EEG abnormalities, comparisons of performance on the 2 sides of the body, differential score approaches, and the investigation of particular learning disabilities. These studies indicate that cerebral impairment is at least one crucial factor limiting the satisfactory adaptation of children with learning disabilities. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
The simplicity of centralized disaster recovery planning is gone forever for many users. It has been replaced with an incredibly complex array of questions and issues that must be explored and resolved. Many factors contribute to this complexity and this article identifies and explores some of them.  相似文献   
106.
While many users appear to believe that the Internet has already become the somewhat nebulously defined Information Superhighway discussed in world media, it is not yet clear that this transformation will ever occur. This article examines a few of the fundamental issues and questions that must be addressed and resolved before a clear picture emerges.  相似文献   
107.
Vascular catheters coated with antiinfective compounds were evaluated as to their ability to prevent Staphylococcus aureus catheter infection in a rabbit model. Zones of inhibition of agar surface-plated S. aureus demonstrated the following hierarchy: dicloxacillin and clindamycin were each better than fusidic acid or chlorhexidine, which were better than ciprofloxacin, cefotaxime, or cefuroxime. In vivo half-lives of inhibitory activity for clindamycin and dicloxacillin were 5.6 and 17.7 h, respectively, with apparent first-order kinetics. Chlorhexidine disappeared in vivo with apparent two-compartment kinetics: first-compartment t1/2, 16.8 h; second-compartment t1/2, 115.6 h. In a rabbit model, dicloxacillin, clindamycin, fusidic acid, and chlorhexidine decreased the risk of infection compared with uncoated control catheters (P < .05). For dicloxacillin, clindamycin, and chlorhexidine, this was true even if the S. aureus inoculation was delayed 48 or 96 h after catheter implantation. These data suggest that vascular catheters with antiinfective coatings should be investigated further in hospitalized patients.  相似文献   
108.
109.
Process capability indices are widely used to measure process performance. In situations such as selecting a supplier and assessing process improvement, it is of interest to compare capability indices for two different processes or the same process before and after an adjustment. In this paper, we consider several methods for performing this comparison on the indices Cpk and Cpm. The methods are compared using a computer simulation. Recommendations are provided for selecting an appropriate method based on power and test size computations.  相似文献   
110.
The role of the central nucleus of the amygdala on olfactory heart rate conditioning in the infant rat was investigated. The conditioned stimulus (CS) consisted of a 10-s presentation of grape juice odor that was immediately followed by a 0.5-s, 0.35-mA subcutaneous shock. A sensitization control group was also run. Three days prior to testing, Ss received either bilateral electrolytic lesions of the central nucleus of the amygdala, sham lesions, or were left unperturbed. Results show that damage to the central nucleus of the amygdala severely impaired olfactory heart rate conditioning but that it had no deleterious effect on the heart rate orienting response to that stimulus or on the heart rate unconditioned response (UCR) to shock. Results are analogous to those in previous research on auditory heart rate conditioning and suggest that the central nucleus of the amygdala may constitute a necessary stage in the transduction of the CS into a cardiac conditioned response (CR) regardless of sensory modality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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