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21.
Thompson Robert J.; Gil Karen M.; Keith Barbara R.; Gustafson Kathryn E.; George Linda K.; Kinney Thomas R. 《Canadian Metallurgical Quarterly》1994,62(4):856
Rates of poor psychological adjustment of children with sickle cell disease remained relatively constant over initial and follow-up assessment points. 50 children (aged 7–12 yrs) and their mothers completed the initial protocol. 30 children completed the follow-up plus 5 additional children and their mothers. These Ss were aged 7–24 yrs at follow-up. With initial levels of adjustment controlled, children's strategies for coping with pain accounted for a significant increment in child-reported symptoms and mother-reported internalizing behavior problems at follow-up beyond the contribution of illness and demographic parameters and follow-up interval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
V Blanc P Gil N Bamas-Jacques S Lorenzon M Zagorec J Schleuniger D Bisch F Blanche L Debussche J Crouzet D Thibaut 《Canadian Metallurgical Quarterly》1997,23(2):191-202
Dextran has been used as a carrier molecule for the synthesis of monofunctional peptide-dextran conjugates. The immunodetection of such carrier immobilized peptides on ELISA plates was compared to that of peptides adsorbed directly to immunoplates. The main features observed with peptide-dextran conjugates were as follows: only small amounts of peptide (1-2 mg) were necessary for coupling via alpha- or epsilon-amino groups to NaIO4-activated dextran (4 mg); the coupling yield was up to 68%; an amino acid analysis of the conjugate enabled the amount of carrier immobilized peptide to be calculated; an estimated 15-17 peptides were bound per dextran molecule (MW 73,500); using a carbohydrate as carrier reduces the possibility of non-specific interactions because no hydrophobic or ionic sites and no protein-like epitopes exist on the carrier apart from the peptide ligand. It can be assumed that some peptide ligands provide the forces for an interaction with the plate surface whereas other remain free for the interaction with the antibody. Thus, the detection with monoclonal anti-peptide antibodies allowed peptide-dextran conjugates to be used at coating concentrations of 1-3 nM peptide, corresponding to 0.6-2.6 ng peptide-dextran per well. In contrast, concentrations of 150-500 nM were required for coating with peptides. The applicability of monofunctional peptide-dextran conjugates was demonstrated by investigating the titer and specificity of a polyclonal anti-peptide serum developed against human gastrointestinal glutathione peroxidase. The introduction of biotin as a second ligand of the dextran conjugate permitted its capture on streptavidin coated plates. This synthesis of bifunctional peptide-biotin-dextran conjugates opens up additional possibilities for applications. 相似文献
23.
Preparation and characterisation of vanadium catalysts supported over alumina-pillared clays 总被引:1,自引:0,他引:1
M. A. Vicente C. Belver R. Trujillano M. A. Baares-Muoz V. Rives S. A. Korili A. Gil L. M. Gandía J. -F. Lambert 《Catalysis Today》2003,78(1-4):181-190
Supported vanadium-containing catalysts were prepared by impregnation of Al-pillared clays with NaVO3 precursor aqueous solutions. A montmorillonite and a saponite, both natural as well as previously pillared with Al13-Keggin polycations, were used as supports, being impregnated with solutions of the precursor by means of the incipient wetness technique. The layered structure of the supports is maintained after impregnation, and even after calcination of the impregnated solids at 500 °C, although with a significant worsening of the textural properties of the solids, in particular, a loss of specific surface area. Three crystalline vanadium-containing phases were identified in the impregnated solids, namely, NaV3O8, AlVO4 and V2O5 (shcherbinaite). The reduction of these phases to V3+ species was observed as wide processes in the 450–750 °C range, all of them centred at ca. 600 °C. 相似文献
24.
Alvaro E. Gil Author Vitae Author Vitae 《Automatica》2006,42(2):245-250
Resource allocation involves deciding how to divide a resource of limited availability among multiple demands in a way that optimizes current objectives. In this brief paper we focus on one type of distributed resource allocation problem where via an imperfect communication network multiple processors can share the load presented by multiple task types. We introduce asynchronous “cooperative” resource allocation strategies, and show that they lead to a bounded cumulative demand. 相似文献
25.
EF Harouche 《Canadian Metallurgical Quarterly》1995,96(6):1451-1453
A small contribution is made to the dependable keyhole pattern in breast reduction. A double dermal modified keyhole closure is described. It is a simple, versatile, and adaptable method of closure regardless of the pedicle technique used for reduction mammaplasty. A triangular flap (skin and dermis) is incorporated on the medial keyhole flap. A deepithelialized dermal flap is created on the lateral keyhole flap. In the final closure of the wound, the medial triangular flap is sutured over the lateral deepithelialized dermal flap. A double dermal closure at the inverted T region is thereby created. The frequency of occurrence of wound spread and early postoperative wound dehiscence is decreased by this closure, which provides cosmetic improvement and wound support where it is needed the most. 相似文献
26.
An acute pulpalgia and temporomandibular disorders can produce many of the same symptoms. To illustrate identification of an acute pulpalgia as a component in TMD, the authors review the evaluation of 11 patients at a clinic that specializes in TMD treatment. During the evaluation, thermal testing and periodontal ligament anesthesia were used to identify the offending tooth. After receiving endodontic treatment or having the tooth extracted, patients reported either complete or partial relief of TMD symptoms. The authors provide questions that may help practitioners identify a tooth with an acute pulpalgia as a contributing factor to TMD symptoms and suggest a technique to confirm this diagnosis. 相似文献
27.
PURPOSE: Retrospective studies suggest that adult patients with intractable epilepsy may have a history of febrile seizures in childhood. Risk factors for a febrile seizure may include the rate of increase in the core temperature (T-core), its peak (Tmax), the duration of the temperature increase, or an underlying brain pathology. Recently, neuronal migration disorders (NMD) have been diagnosed with increasing frequency in patients with epilepsy, but the link between NMD, febrile seizures, and epilepsy is unclear. We studied rat pups rendered hyperthermic to ascertain the incidence of seizures, mortality, and extent of hippocampal cell loss in each group. METHODS: We exposed 14-day-old rat pups with experimentally induced NMD (n = 39) and age-matched controls (n = 30) to hyperthermia (core body temperature > 42 degrees C). RESULTS: The incidence of hyperthermia-induced behavioral seizures and mortality rate were significantly higher in rats with NMD than in controls (p < 0.05). The longer duration of hyperthermia resulted in a higher incidence of behavioral seizures and higher mortality rate (p < 0.05). In rats with NMD, hyperthermia resulted in hippocampal pyramidal cell loss independent of seizure activity; the extent of neuronal damage correlated positively with the duration of hyperthermia. In control rats, occasional neuronal loss and astrocytosis occurred only after prolonged hyperthermia. CONCLUSIONS: In immature rats, NMD lower the threshold to hyperthermia-induced behavioral seizures and hyperthermia in the presence of NMD may cause irreversible hippocampal neuronal damage. 相似文献
28.
We analysed rates of detection for smear abnormalities in 255,000 women served by the Bristol screening programme. The programme began in 1966 with the aim of eradicating the 30-40 deaths each year in Bristol from cervical cancer. Organisation has been good and population uptake has been high for the past 15 years. Records were computerised in 1977. During the 1988 to 1993 screening round, 225,974 women were tested. New smear abnormalities were found in 15,551, of whom nearly 6000 were referred for colposcopy. These numbers are excessively high in comparison with the incidence of the malignancy we are trying to prevent. The effect of screening on death rates in Bristol is too small to detect. Our conclusion is that despite good organisation of the service, much of our effort in Bristol is devoted to limiting the harm done to healthy women and to protecting our staff from litigation as cases of serious disease continue to occur. The real lesson from 30 years' cervical screening is that no matter how obvious the predicted benefit may seem for any screening test, introduction should never take place without adequate prior evaluation of both positive and negative effects in controlled trials. 相似文献
29.
The exposure to paired electric impulses and vibromassage promotes completeness of repair in the treatment of injured peripheral nerves of the limb. The effect is achieved due to marked stimulation of myelinization and differentiation of the nerve fibers, regeneration of the nerve system in the denervated muscle. 相似文献
30.