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JP Larsen H Odegaard E Tandberg A H?dneb? D Aarsland 《Canadian Metallurgical Quarterly》1996,9(4):157-163
As hypersensitivity to natural rubber latex (NRL) has become an increasingly recognized problem in children, identification of all groups at risk seems important. In this study hypersensitivity to NRL was evaluated in 337 children with potential risk factors. We identified by questionnaire children's underlying diseases, history of surgical procedures, evidence of atopy and patient's history of NRL-specific reactions. Hypersensitivity to NRL and other allergens relevant in the Düsseldorf area was evaluated by skin prick test and specific IgE. In 9.2% of all children hypersensitivity to NRL was observed. Significant risk factors for hypersensitivity to NRL were, among the underlying diseases, spina bifida (odds ratio 29.2), hydrocephalus internus (10.1), gastrointestinal malformation (5.2) and atopy (2.2). Surgical procedures with significant risk were the implantation of a ventriculo-peritoneal shunt (15.7) and surgery of the gastrointestinal tract (3.1). Frequency of surgical procedures correlated (p < 0.001) with risk of hypersensitivity. Frequent surgery and atopy were found to have an additional effect on the risk of hypersensitivity. Information about previous NRL-specific reactions obtained by questionnaire was of little predictive value when performing multivariate analysis. For children at high risk for hypersensitivity to NRL preoperative evaluation and, in case of hypersensitivity, preventive measures seem to be advised. 相似文献
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JJ Harris DK Lunt SB Smith WL Mies DS Hale M Koohmaraie JW Savell 《Canadian Metallurgical Quarterly》1997,75(4):986-992
Two groups of Brangus steers produced by nuclear transplantation cloning were used in parallel studies investigating the impact of calf- and yearling-feeding. The first group (n = 8) were fed as calves (CF; n = 4) or yearlings (YF; n = 4) to a constant age end point of 16 mo. The second group (n = 10) were fed as calves (CF; n = 5) or yearlings (YF; n = 5) to a constant live weight end point (530 kg). When slaughtered at the same age, CF and YF steers did not differ (P > .05) in feedlot ADG, but the CF steers were heavier and had higher dressing percentages, numeric yield grades, and quality grades (P < .05). Top loin steaks from the groups of steers did not differ (P > .05) in palatability traits. When fed to a constant live weight, the YF steers gained more rapidly (P < .05) and had lower (P < .05) numeric yield grades than did CF steers. Again CF steers had higher (P < .05) dressing percentages. There was no difference (P > .05) between the treatments in carcass quality grade or meat palatability characteristics. Thus, when finished to a constant weight end point, YF steers gained more rapidly, with no adverse effects on carcass quality grade or palatability traits; however, CF steers consistently produced higher dressing percentages, largely due to greater external fatness. 相似文献
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A set of six coals ranging in rank from lignite to hvA bituminous was swollen with a series of alkyl-substituted pyridines and a smaller set of 4-alkylanilines. The size and branching of the alkyl groups was varied and the effect of this variation on the dissolution of the amines in the coal and the resulting coal swelling was measured volumetrically. In a few cases, substituents which hindered the amine nitrogen were studied. The lignite and subbituminous coal have a much higher tolerance to branched, bulky groups than do the bituminous coals. The presence of tertiary groups in a solute strongly inhibits their dissolution in bituminous coals. Bituminous coals behave as if extensive parallel packing of structures occurs. Often, they can accept very large planar groups but have a low capacity for branched groups. 相似文献
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SB McNeil 《Canadian Metallurgical Quarterly》1997,23(3):287-8; discussion 289-90, 317
Jehovah's Witnesses refuse blood transfusions for themselves and for their children. This action can be difficult for health professionals to understand and can lead to tensions between the staff and family. For one family, their refusal of blood for their child lead to a greater understanding of their religion and its beliefs for those who cared for them. Interspersed with their story are the medical reasons their son required blood, the reasons Jehovah's Witnesses refuse blood transfusions, and what the acceptable alternatives are to Jehovah's Witnesses. This article will share the thoughts and feelings of the family and the nursing staff who cared for the family during this crisis. 相似文献
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We report a comprehensive crosstalk investigation of a packaged InGaAsP/InP 4×4 semiconductor optical amplifier gate switch matrix, experimentally as well as theoretically. For a fully loaded switch with the same wavelength on all four inputs, all possible switching combinations are analyzed, thus yielding realistic crosstalk figures. Coherent and incoherent crosstalk phenomena are identified, and a switch crosstalk less than -40 dB has been measured 相似文献
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The majority of patients with soft tissue or bone sarcomas of the upper extremity can be treated today with limb-saving procedures using combined modality therapies. For patients with a tumor in the shoulder area, sometimes an interscapulothoracic amputation is the only radical surgical treatment. However, in selected cases, in which the tumor does not involve the neurovascular bundle, a limb-sparing alternative might be the Tikhoff-Linberg resection. Normal function of the hand and forearm, with reasonable function of the elbow, can be maintained by this procedure. Four case histories are reported. 相似文献
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