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131.
Two methods of endotracheal intubation of patients lying on the ground were compared for ease and speed of intubation and minimization of complications in a crossover study of prehospital-oriented emergency physicians. Intubation of a mannequin was attempted by the physicians in either a left lateral decubitus (LLD) position or a kneeling (K) position, followed by the alternate position. The LLD position afforded more rapid intubation, better glottic visualization, and less dental trauma. Eighty-seven percent of physicians completely visualized the glottis in the LLD position, versus 33% of the K position group. Intubation times were 10.5 versus 14.6 seconds in the LLD and K positions, respectively (P < .001). The LLD position is a more effective position (in a mannequin model) than the K position for intubation of patients found lying on the ground, a frequent situation in prehospital care. 相似文献
132.
ELO2 and ELO3 were identified from the Saccharomyces cerevisiae genome data base as homologues of ELO1, a gene involved in the elongation of the fatty acid 14:0 to 16:0. Mutations in these genes have previously been shown to produce pleiotropic effects involving a number of membrane functions. The simultaneous disruption of ELO2 and ELO3 has also been shown to produce synthetic lethality, indicating that they have related and/or overlapping functions. Gas chromatography and gas chromatography/mass spectroscopy analyses reveal that null mutations of ELO2 and ELO3 produce defects in the formation of very long chain fatty acids. Analysis of the null mutants indicates that these genes encode components of the membrane-bound fatty acid elongation systems that produce the 26-carbon very long chain fatty acids that are precursors for ceramide and sphingolipids. Elo2p appears to be involved in the elongation of fatty acids up to 24 carbons. It appears to have the highest affinity for substrates with chain lengths less than 22 carbons. Elo3p apparently has a broader substrate specificity and is essential for the conversion of 24-carbon acids to 26-carbon species. Disruption of either gene reduces cellular sphingolipid levels and results in the accumulation of the long chain base, phytosphingosine. Null mutations in ELO3 result in accumulation of labeled precursors into inositol phosphoceramide, with little labeling in the more complex mannosylated sphingolipids, whereas disruption of ELO2 results in reduced levels of all sphingolipids. 相似文献
133.
Congenital anomalies of the thoracic veins are infrequent but important developmental abnormalities. Thoracic venous anomalies can be classified as systemic or pulmonary. Systemic venous anomalies are often incidental findings, whereas pulmonary venous anomalies are more likely to manifest with cyanosis and to be associated with congenital cardiac abnormalities, especially atrial septal defect. Magnetic resonance (MR) imaging provides excellent delineation of the abnormal vessels and associated cardiac defects. Conventional spin-echo (SE) techniques show blood flow as a signal void and are sufficient for demonstrating the aberrant venous anatomy in most cases. Gradient-echo images show flowing blood as high signal intensity and are useful for clarifying the course of anomalous veins when vessel walls are difficult to visualize on SE images. Phase-contrast images are valuable for ascertaining the direction of blood flow and thus provide a physiologic method of distinguishing the vertical vein of anomalous pulmonary venous return from a left superior vena cava. MR imaging is useful for delineating both the thoracic venous and accompanying intracardiac anomalies and is a valuable, complementary technique to echocardiography, angiography, and computed tomography in the evaluation of patients with these abnormalities. 相似文献
134.
G Johnson PW Burvill CS Anderson K Jamrozik EG Stewart-Wynne TM Chakera 《Canadian Metallurgical Quarterly》1995,91(4):252-257
Evaluation of the relative efficacy of three screening instruments for depression and anxiety in a group of stroke patients was undertaken as part of the Perth community stroke study. Data are presented on the sensitivity and specificity of the Hospital Anxiety and Depression Scale (HAPS), the Geriatric Depression Scale and the General Health Questionnaire (GHQ) (28-item version) in screening patients 4 months after stroke for depressive and anxiety disorders diagnosed according to DSM-III criteria. The GHQ-28 and GDS but not the HADS depression, were shown to be satisfactory screening instruments for depression, with the GHQ-28 having an overall superiority. The performance of all 3 scales for screening post-stroke anxiety disorders was less satisfactory. The HADS anxiety had the best level of sensitivity, but the specificity and positive predictive values were low and the misclassification rate high. 相似文献
135.
Vaccinia virus has a wide host range and infects mammalian cells of many different species. This suggests that the cell surface receptors for vaccinia virus are ubiquitously expressed and highly conserved. Alternatively, different receptors are used for vaccinia virus infection of different cell types. Here we report that vaccinia virus binds to heparan sulfate, a glycosaminoglycan (GAG) side chain of cell surface proteoglycans, during virus infection. Soluble heparin specifically inhibits vaccinia virus binding to cells, whereas other GAGs such as condroitin sulfate or dermantan sulfate have no effect. Heparin also blocks infections by cowpox virus, rabbitpox virus, myxoma virus, and Shope fibroma virus, suggesting that cell surface heparan sulfate could be a general mediator of the entry of poxviruses. The biochemical nature of the heparin-blocking effect was investigated. Heparin analogs that have acetyl groups instead of sulfate groups also abolish the inhibitory effect, suggesting that the negative charges on GAGs are important for virus infection. Furthermore, BSC40 cells treated with sodium chlorate to produce undersulfated GAGs are more refractory to vaccinia virus infection. Taken together, the data support the notion that cell surface heparan sulfate is important for vaccinia virus infection. Using heparin-Sepharose beads, we showed that vaccinia virus virions bind to heparin in vitro. In addition, we demonstrated that the recombinant A27L gene product binds to the heparin beads in vitro. This recombinant protein was further shown to bind to cells, and such interaction could be specifically inhibited by soluble heparin. All the data together indicated that A27L protein could be an attachment protein that mediates vaccinia virus binding to cell surface heparan sulfate during viral infection. 相似文献
136.
We report four cases of multiple symmetric lipomatosis in the Chinese population. We believe that multiple symmetric lipomatosis in the Chinese is not uncommon and may be related to the increasing incidence of alcoholism. The ultrasound appearances of these lipomatous masses are presented for the first time. Heterogeneous echogenic masses with fine fibrous strands that insinuate around fascial planes, lymph nodes and vascular tissues are typical findings. Unlike diseases affecting the Western population, multiple symmetric lipomatosis in the Chinese appears to be limited to the head and neck. 相似文献
137.
S Song CY Lee ML Green CS Chung RC Simmen FA Simmen 《Canadian Metallurgical Quarterly》1996,120(2):193-202
Nisin was first introduced commercially as a food preservative in the UK approximately 30 years ago. First established use was as a preservative in processed cheese products and since then numerous other applications in foods and beverages have been identified. It is currently recognised as a safe food preservative in approximately 50 countries. The established uses of nisin as a preservative in processed cheese, various pasteurised dairy products, and canned vegetables will be briefly reviewed. More recent applications of nisin include its use as a preservative in high moisture, hot baked flour products (crumpets) and pasteurised liquid egg. Renewed interest is evident in the use of nisin in natural cheese production. Considerable research has been carried out on the antilisterial properties of nisin in foods and a number of applications have been proposed. Uses of nisin to control spoilage lactic acid bacteria have been identified in beer, wine, alcohol production and low pH foods such as salad dressings. Further developments of nisin are likely to include synergistic action of nisin with chelators and other bacteriocins, and its use as an adjunct in novel food processing technology such as higher pressure sterilisation and electroporation. Production of highly purified nisin preparations and enhancement by chelators has led to interest in the use of nisin for human ulcer therapy, and mastitis control in cattle. 相似文献
138.
Developmental expression and location of IGF-I and IGF-II mRNA and protein in skeletal muscle 总被引:1,自引:0,他引:1
To investigate the role of IGF in muscle development in vivo, developmental expression and location of IGF-I and -II protein and mRNA were examined in fetal, postnatal, and adult skeletal muscle. Muscle tissue was collected from 30-, 44-, 59-, 68-, 75-, 89-, and 109-d porcine fetuses, 21-d neonatal pigs, and 6-mo-old (adult) pigs. Relative amounts of IGF-II mRNA peaked (P < .05) in 59-d fetal muscle and decreased thereafter. Inversely, muscle IGF-I expression increased (P < .05) to maximal levels around birth. For in situ hybridization, frozen muscle tissue sections (10 microm) were hybridized with a hydrolyzed form of the same riboprobes or incubated with polyclonal or monoclonal antibodies to IGF-I or -II, respectively. The majority of IGF-I and IGF-II mRNA was localized to developing muscle fibers, whereas little signal was found in the surrounding connective tissues. Immunofluorescent localization of IGF-I and -II confirmed that muscle IGF are present in developing muscle fibers. Collectively, these data show that IGF-I and -II are expressed and produced primarily in muscle cells within developing muscle tissue and support the hypothesis that IGF-I and -II modulate fetal muscle development. 相似文献
139.
2-Ketocyclohexanecarboxyl coenzyme A (2-ketochc-CoA) hydrolase has been proposed to catalyze an unusual hydrolytic ring cleavage reaction as the last unique step in the pathway of anaerobic benzoate degradation by bacteria. This enzyme was purified from the phototrophic bacterium Rhodopseudomonas palustris by sequential Q-Sepharose, phenyl-Sepharose, gel filtration, and hydroxyapatite chromatography. The sequence of the 25 N-terminal amino acids of the purified hydrolase was identical to the deduced amino acid sequence of the badI gene, which is located in a cluster of genes involved in anaerobic degradation of aromatic acids. The deduced amino acid sequence of badI indicates that 2-ketochc-CoA hydrolase is a member of the crotonase superfamily of proteins. Purified BadI had a molecular mass of 35 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a native molecular mass of 134 kDa as determined by gel filtration. This indicates that the native form of the enzyme is a homotetramer. The purified enzyme was insensitive to oxygen and catalyzed the hydration of 2-ketochc-CoA to yield pimelyl-CoA with a specific activity of 9.7 micromol min(-1) mg of protein(-1). Immunoblot analysis using polyclonal antiserum raised against the purified hydrolase showed that the synthesis of BadI is induced by growth on benzoate and other proposed benzoate pathway intermediates but not by growth on pimelate or succinate. An R. palustris mutant, carrying a chromosomal disruption of badI, did not grow with benzoate and other proposed benzoate pathway intermediates but had wild-type doubling times on pimelate and succinate. These data demonstrate that BadI, the 2-ketochc-CoA hydrolase, is essential for anaerobic benzoate metabolism by R. palustris. 相似文献
140.
N Mach CS Lantz SJ Galli G Reznikoff M Mihm C Small R Granstein S Beissert M Sadelain RC Mulligan G Dranoff 《Canadian Metallurgical Quarterly》1998,91(3):778-783
The in vivo functions of interleukin-3 (IL-3) were investigated by generating IL-3-deficient mice. Although hematopoiesis was unimpaired in homozygous mutant animals, contact hypersensitivity reactions were compromised. IL-3 was required for efficient priming of hapten-specific contact hypersensitivity responses, but was dispensable for T-cell-dependent sensitization to tumor cells. These findings reveal a critical role for IL-3 in some forms of delayed-type hypersensitivity. 相似文献