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961.
The marginal granulocyte pool (MGP) was measured by epinephrine infusion in normal and neutropenic subjects. Neutrophil response curves to doses of 0.025 to 0.3 mg. in three normal subjects indicated that maximal neutrophil response was achieved by 0.1 mg. In 21 normal subjects, absolute neutrophils increased from 700 to 3,100 per microliter. The percentage increase ranged from 18 to 107 per cent of baseline. The per cent increase tended to be greater with low-normal baseline neutrophils than with high-normal neutrophils, although this relationship was not observed when increase was determined in absolute values. In neutropenic patients mean per cent increase of neutrophils was greater than observed in normal subjects, 121 vs. 50 per cent. Although the increase expressed in absolute neutrophil numbers was less in subjects with lower baseline neutrophil concentrations, there was an inverse correlation between the baseline neutrophil concentrations, there was an inverse correlation between the baseline neutrophils and the per cent increment following epinephrine. Mean increase was 200 per cent in patients with less than 200 neutrophils per microliter, compared with 61 per cent in patients with 1,000 to 1,500 neutrophils per microliter. These results indicate that circulating granulocyte pool (CGP) size may be misleading with respect to total blood neutrophils and in a sense confirm the concept of shift neutropenia, a decreased CGP and MGP as neutropenia becomes more profound suggests that shift neutropenia may be a normal physiologic methanism rather than a distinct neutropenic syndrome.  相似文献   
962.
Studies were undertaken to determine the component(s) responsible for the temperature optimum characteristic of the protein-synthesizing system from skate and rat. 1. The macromolecular constituents of rat and skate liver ribosomes are compared. The number of ribosomal proteins is similar in the two species, although most proteins display different electrophoretic mobilities on polyacrylamide gels. The RNAs from the small subunit of skate and rat have similar sedimentation coefficients; however, the RNA from the large subunit of skate ribosomes appeared to be slight smaller than the comparable RNA from the rat. 2. Ribosomes from either rat or skate were capable of supporting poly(U)dependent polyphenylalanine synthesis with soluble factors from either species. 3. Maximal leucine incorporation directed by endogenous mRNA occurred at 35--40 degrees C with post-mitochondrial supernatant from the rat liver and at 20--30 degrees C with that from skate liver. 4. The characteristic temperature sensitivity of protein synthesis was dependent upon the source of cell sap and independent of the source of ribosomes. 5. Elongation factor 1 from both the rat and skate exhibited maximum activity at approx. 30 degrees C. 6. Phenylalanyl-tRNA synthetase from skate liver showed maximum activity at 30 degrees C while that from rat was maximally active at 37 degrees C. The rat enzyme, however, was active at 0--10 degrees C, at which temperature protein synthesis in the reconstructed rat system is virtually absent. 7. The protein-synthesizing capacity of the reconstituted system at various temperatures was closely correlated with the activity of Elongation factor 2 (translocase). Elongation factor 2 from rat liver displayed an optimum at 30 degrees C and lost all activity below 10 degrees C, while this same factor from skate liver showed an optimum at 20 degrees C and significant activity below 10 degrees C. At this low temperature the reconstituted skate liver system continued to exhibit the ability to synthesize protein. These studies suggest that Elongation factor 2 is the component responsible for determining the temperature at which the protein-synthesizing system displays its characteristic maximum activity.  相似文献   
963.
The gastric emptying rate of an isotopically labelled solid meal was compared in 29 insulin-dependent well-controlled diabetics and 18 normal controls. The diabetics were assessed for evidence of autonomic neuropathy. No significant difference in gastric emptying rate was found between controls and diabetics with or without autonomic neuropathy. Only three diabetics had greatly delayed gastric emptying, but in one of these the test had given a normal result on an earlier occasion.  相似文献   
964.
Five hundred fourty-seven consecutive forearm fractures in children were studied, with special emphasis on complications encountered. The most important apparent conclusion reached from this study is that greenstick and complete fractures are different, and that some of the pitfalls and complications seen following these injuries can be avoided if different methods of reduction are used for each. Greenstick fractures should be reduced by manipulating them into the correct proper plane of rotation; i.e., maximum pronation for distal third fractures, neutral for middle third fractures, and supination for proximal third fractures. Application of this familiar "rule of thirds" to complete fractures, however, may result in ratational deformity at the fracture site. Completer fractures should be reduced by finger trap traction, allowing the fracture to seek its own level of rotation. Several other observations were also noted. Angulation into radial deviation was found to remodel and equally as well as volar angulation, and remodeling may contine for as long as two years after injury. Growth disturbance following fractures through the distal radial epiphyseal plate is uncommon, but premature closure of the epiphysis did occur in one patient with a typical Type II fracture. Six concomitant nerve injuries were seen; all recovered spontaneously within 3 weeks.  相似文献   
965.
966.
A survey of 29 laboratory populations of Drosophila melanogaster for glutamate oxaloacetate transaminase (GOT) variation revealed that the Got-1 locus was polymorphic in three stocks recently collected from nature. The Got-1 locus was fixed for the same allozyme in the remaining 26 laboratory populations. Testcross matings to multiply marked stocks established that Got-1 is located at 4.8 centimorgans on chromosome 2.  相似文献   
967.
The aim of our work was to detect Listeria monocytogenes in raw whole milk from five municipalities of Boyacá-Colombia using real-time PCR. A PCR hybridization probe format was used to analyze the presence of L. monocytogenes, using specific primers to amplify a 149 bp fragment from the metalloprotease gene (mpl). In this study on a total number of 81 samples, 21 gave positive results for L. monocytogenes by real-time PCR and 13 samples were positive by conventional method. These results indicate a high presence of this pathogen in this area of the country and that this method is considerably faster than current standard methods.  相似文献   
968.
Response of lowland rice to sources and methods of nitrogen fertilizer application were summarized for more than 100 experiments. In about 2/3 of the experiments, the yield increase per kg of fertilizer N was judged to be relatively poor with best split applications of urea. Based on frequency distribution, sulfur coated urea and urea briquets or urea supergranules deep placed more often produced satisfactory yield increases than best split urea, but even with these sources/methods the yield increases were judged to be relatively poor in about 1/2 of the experiments. There is an enormous potential to increase rice production with no further increases in inputs of fertilizer N if we could learn to match the best method/source of fertilizer with the soil-crop management complex.About 60% of the yields with no fertilizer N were in the range of 2 to 4 t/ha. Based on the average yield response to urea, this is equivalent to about 100 kg of urea N. It would appear worthwhile to study ways to improve utilization of soil nitrogen since it is already in place on the land and apparently in fairly abundant amounts in many soils.About 50 experiments with15N fertilizers were summarized. In almost all cases, the uptake of tagged fertilizer was less than the net increase in N in the above ground matter. In about 2/3 of the experiments, the addition of fertilizer N increased soil N uptake more than 20% and in 1/3 of the experiments the uptake of soil N was increased more than 40%. These results lead to much uncertainty about practical interpretation and use of15N data.  相似文献   
969.
    
The increasing popularity of multi‐player online games is leading to the widespread use of large‐scale Distributed Virtual Environments (DVEs) nowadays. In these systems, peer‐to‐peer (P2P) architectures have been proposed as an efficient and scalable solution for supporting massively multi‐player applications. However, the main challenge for P2P architectures consists of providing each avatar with updated information about which other avatars are its neighbors. This problem is known as the awareness problem. In this paper, we propose a comparative study of the performance provided by those awareness methods that are supposed to fully solve the awareness problem. This study is performed using well‐known performance metrics in distributed systems. Moreover, while the evaluations shown in the literature are performed by executing P2P simulations on a single (sequential) computer, this paper evaluates the performance of the considered methods on actually distributed systems. The evaluation results show that only a single method actually provides full awareness to avatars. This method also provides the best performance results. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
970.
    
Tangerine (Citrus reticulata blanco) juice clarification by crossflow microfiltration and ultrafiltration using polysulphone flat sheet membranes with nominal molecular weight cut off of 25,000, 50,000, 100,000 and 0.1 μm, 0.2 μm pore sizes was studied. the juice was pretreated by polygalacturonase and pH adjustment. the treated juice was clarified with a laboratory scale filtration unit with effective filtration area of 14 cm2. Filtration conditions were transmembrane pressure of 93 to 194 kPa, crossflow velocity of 0.96 to 3.5 m/s and 25°C. Membrane performance was evaluated in terms of volume flux and clarity (% transmittance) of the permeate. Pretreatment of the juice by polygalacturonase and adjustment to pH 2 with HCl resulted in a clearer supernatant than enzyme treatment alone. Maximum flux was obtained with the 0.1 μm microfiltration membrane. Flux increased with transmembrane pressure and crossflow velocity. Flux at 194 kPa and 3.5 m/s was 69 L per square meter per hour. Permeate clarity was better at higher transmembrane pressure and lower velocity, due to the effect of the polarized/fouling layer of solute on the membrane surface, which acted as a secondary “dynamic” filter.  相似文献   
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