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In order to consider the response of concrete columns confined by FRP and FRCM system, proper models have to be formulated. In this context the present paper shows a generalized criterion for the determination of the increase in strength, in ductility and in dissipated energy for varying corner radius ratio of the cross section and fiber volumetric ratio. The procedure is based on the best fitting of several experimental data and unlike the usual empirical approaches available in the literature, the proposed technique relates the confinement effectiveness to a single parameter representative of the relative stiffness between the original concrete core and the reinforcement system. Furthermore, the proposed analytical models overcomes the limit of many empirical or semi-empirical models given in the literature that are applicable only to specific cases. A comparison with same available models confirm the reliability of the proposed procedure.  相似文献   
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The presence of corticosteroid residues was assessed in urine and liver samples from livestock of Sicily. A total of 630 bovine samples were collected from farms and slaughterhouses. The samples were analysed using solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). All the corticosteroids found were under the maximum residue limit imposed by Commission Regulation (EC) 37/2010. About 4% of liver samples showed dexamethasone levels above the limit of detection (LOD), with a mean of 1.5 ± 0.2 µg kg?1. Betamethasone was found only in seven liver samples, with a mean of 1.6 ± 0.1 µg kg?1. Furthermore, prednisolone and prednisone were found only in urine and liver samples from slaughterhouse, probably related to the high rate of stress for bovines. These results suggest good control practices adopted by Sicilian farms, able to ensure the quality of food products.  相似文献   
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224 patients with a recent diagnosis of chronic lymphocytic leukemia, confirmed by immune phenotype, were studied with a mean follow-up of 16 months. The median age was 72 years and the ratio of men to women was 1.51. An incidental diagnosis because of leukocytosis was made in 75% of the patients; in only 22% was the diagnosis related to symptoms. 80% were in stage A, 7.5% in stage B, and 12.5% in stage C. A relation was found between advanced stage and the number of lymphocytes in the blood, the percentage of lymphocytes in the bone marrow, WHO performance status, bacterial infection and disease-related mortality. Thus, six patients in stage C (21%) died because of infection (septicaemia or pneumonia), as opposed to only one out of 196 patients in stages A and B. The incidence of bacterial infection was 64% in stage C, as compared to 8.3% in stage A. Treatment with chlorambucil, started in 59 patients, was in accordance with the guidelines of the national programme for 52 of them. In contrast, a strict indication for prednisone (autoimmune cytopenia) was found in only 42% of 42 patients given this treatment.  相似文献   
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Research on nonhuman primates suggests that the primary taste cortex in humans is located in the rostrodorsal insula. Qualitative and quantitative assessment of taste perception was performed on 6 patients with unilateral damage to the insula, 3 patients with brain damage outside the insula, and 11 age-matched, normal subjects. Each subject identified the quality and intensity of the gustatory stimuli applied separately to the left and right sides of the anterior tongue. Damage to the right insula produced ipsilateral taste recognition and intensity deficits. Damage to the left insula caused an ipsilateral deficit in taste intensity but a bilateral deficit in taste recognition. The unexpected deficit in the left-hemispheric stroke patients for taste recognition on the right side of the tongue suggests that taste information from both sides of the tongue passes through the left insula. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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PURPOSE: The American Urological Association convened the Ureteral Stones Clinical Guidelines Panel to analyze the literature regarding available methods for treating ureteral calculi and to make practice policy recommendations based on the treatment outcomes data. MATERIALS AND METHODS: The panel searched the MEDLINE data base for all articles related to ureteral calculi published from 1966 to January 1996. Outcomes data were extracted from articles accepted after panel review. The data were then meta-analyzed to produce outcome estimates for alternative treatments of ureteral calculi. RESULTS: The data indicate that up to 98% of stones less than 0.5 cm. in diameter, especially in the distal ureter, will pass spontaneously. Shock wave lithotripsy is recommended as first line treatment for most patients with stones 1 cm. or less in the proximal ureter. Shock wave lithotripsy and ureteroscopy are acceptable treatment choices for stones 1 cm. or less in the distal ureter. CONCLUSIONS: Most ureteral stones will pass spontaneously. Those that do not can be removed by either shock wave lithotripsy or ureteroscopy. Traditional blind basket extraction, without fluoroscopic control and guide wires, is not recommended. Open surgery is appropriate as a salvage procedure or in certain unusual circumstances.  相似文献   
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A new transgenic mouse mutagenesis test system has been developed for the efficient detection of point mutations and deletion mutations in vivo. The mice carry lambda EG10 DNA as a transgene. When the rescued phages are infected into Escherichia coli YG6020-expressing Cre recombinase, the phage DNA is converted into plasmid pYG142 carrying the chloramphenicol-resistance gene and the gpt gene of E. coli. The gpt mutants can be positively detected as colonies arising on plates containing chloramphenicol and 6-thioguanine. The EG10 DNA carries a chi site along with the red and gam genes so that the wild-type phages display Spi- (sensitive to P2 interference) phenotype. Mutant phages lacking both red and gam genes can be positively detected as plaques that grow in P2 lysogens of E. coli. These mutant phages are called lambda Spi-. The spontaneous gpt mutation frequencies of five independent transgenic lines were 1.7 to 3.3 x 10(-5) in bone marrow. When the mice were treated with ethylnitrosourea (single i.p. treatments with 150 mg/kg body weight; killed 7 days after the treatments), mutation frequencies were increased four- to sevenfold over the background in bone marrow. The average rescue efficiencies were more than 200,000 chloramphenicol-resistant colonies per 7.5 micrograms bone marrow DNA per packaging reaction. In contrast to gpt mutation frequencies, spontaneous Spi- mutation frequencies were 1.4 x 10(-6) and 1.1 x 10(-6) in bone marrow and sperm, respectively. No spontaneous Spi- mutants have been detected so far in spleen, although 930,000 phages rescued from untreated mice were screened. In gamma-ray-treated animals, however, induction of Spi- mutations was clearly observed in spleen, at frequencies of 1.4 x 10(-5) (5 Gy), 1.2 x 10(-5) (10 Gy), and 2.0 x 10(-5) (5O Gy). These results suggest that the new transgenic mouse "gpt delta" could be useful for the efficient detection of point mutations and deletion mutations in vivo.  相似文献   
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This study aimed at investigating the effects of a novel neck balance system (NBS), which is a baseball cap with counterweights in the occipital part, on neuromuscular fatigue of neck muscles during and after a full‐range repeated neck flexion‐extension task. Surface electromyography (sEMG) of sternocleidomastoid (SCM) and semispinalis capitis (SC) muscles was recorded in 15 healthy individuals during full‐range flexion‐extension movements of the neck lasting 5 min at a fixed pace (1 Hz), with or without NBS. Maximal isometric force and sEMG were recorded before and after the fatiguing task. During the fatiguing task, the SC muscle showed a higher decline in amplitude of sEMG with NBS than without NBS, while no differences in the SCM muscle emerged between the two conditions. Maximal isometric force of both neck flexor and extensor muscles decreased significantly after the fatiguing task, both with NBS (p < .05) and without NBS (p < .05), with no differences between the two conditions. In conclusion, adopting the NBS promotes an increase of the activation of neck extensor muscles, possibly leading to earlier decline of the neuromuscular performance and to diminished ability to actively stabilize neck structures. For these reasons, the adoption of the NBS during dynamic, fatiguing contractions may not be appropriate.  相似文献   
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