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151.
BACKGROUND: The risk for allergic reactions depends on the sensitivity of individuals and the quantities of offending food ingested. The sensitivity varies among allergic individuals, as does the threshold dose of a food allergen capable of inducing an allergic reaction. OBJECTIVE: This study aimed at determining the distribution of minimum provoking doses of hazelnut in a hazelnut-allergic population. METHODS: Thirty-one patients with a history of hazelnut-related allergic symptoms, a positive skin prick test to hazelnut and/or an elevated specific IgE level, were included. Double-blind, placebo-controlled food challenges (DBPCFC) were performed with seven increasing doses of dried hazelnut (1 mg to 1 g hazelnut protein) randomly interspersed with seven placebo doses. RESULTS: Twenty-nine patients had a positive challenge. Itching of the oral cavity and/or lips was the first symptom in all cases. Additional gastrointestinal symptoms were reported in five patients and difficulty in swallowing in one patient. Lip swelling was observed in two patients, followed by generalized urticaria in one of these. Threshold doses for eliciting subjective reactions varied from a dose of 1 mg up to 100 mg hazelnut protein (equivalent to 6.4-640 mg hazelnut meal). Extrapolation of the dose-response curve showed that 50% of our hazelnut-allergic population will suffer from an allergic reaction after ingestion of 6 mg (95% CI, 2-11 mg) of hazelnut protein. Objective symptoms were observed in two patients after 1 and 1,000 mg, respectively. CONCLUSION: DBPCFCs demonstrated threshold doses in half of the hazelnut-allergic patients similar to doses previously described to be hidden in consumer products. This stresses the need for careful labelling and strategies to prevent and detect contamination of food products with hazelnut residues.  相似文献   
152.
The aim of this study was to document the amount of recent change in Australian nurse academics' scholarly productivity and to investigate the influence of demographic factors such as gender, academic rank, qualifications, increase in qualifications, state of residence, university and university size. Scholarly productivity was calculated from an audit of journal articles. The findings of this study indicate that, while there has been a slight increase in scholarly productivity in the last five years, nursing still lags behind other disciplines. Scholarly productivity was found to be positively associated with highest academic qualification, academic rank and promotion. The study indicates the continuing need for senior nurse academics to provide mentoring to colleagues and foster the development of skills associated with scholarly productivity.  相似文献   
153.
Current trend in the treatment of Hodgkin's disease   总被引:1,自引:0,他引:1  
The analysis of three subsequent randomized trials carried out within the frame of the European Organization for Research on Cancer (E.O.R.T.C.) enables to define a strategy for the staging and the treatment of early stages of Hodgkin's disease. Several prognostic factors were identified by multivariate analyses: 1) erythrocyte sedimentation rate, which has a greater impact on relapse-free survival than systemic symptoms but which can be combined with them; the combination of the two is a more powerful prognostic indicator than ESR alone; 2) the number of involved lymphatic areas: patients with one or two lymphatic areas involved (CS I and II2) have a better outcome than stage II patients with 3 or more areas involved (CS II3). Patients with favorable prognostic indicators are submitted to staging laparotomy because for them spleen involvement has a pejorative impact. For patients with unfavorable indicators, the spleen involvement has little prognostic significance and therefore those patients who need, anyway, an aggressive treatment do not undergo staging laparotomy. Patients with favorable prognostic indicators and negative staging laparotomy can be treated by radiotherapy alone, patients with positive laparotomy or patients with unfavorable prognostic indicators are treated by combination of multiple chemotherapy and radiotherapy.  相似文献   
154.
155.
It is stressed that the brain/mind complex constitutes a monolithic system that functions with emergent properties at several levels of hierarchical organization. These hierarchical levels are non-reducible to one another; they are at least three (neuronal, functional, and semantic), and they function within an interactional plan. From the epistemological view-point, the brain/mind complex uses logical and non-logical mechanisms to deal with day-to-day problems. Logic is necessary for the thinking process, but it is not sufficient. Emphasis is given to non-logical mechanisms; fuzzy logic and heuristics, which allow the mind to develop strategies to find solutions, are analysed.  相似文献   
156.
Deep venous thrombosis and pulmonary embolism   总被引:2,自引:0,他引:2  
All surgical patients are at risk for the development of deep venous thrombosis and subsequent pulmonary embolism or postphlebitic syndrome. The evolution of ultrasonographic imaging has increased the awareness of prevention, diagnosis, and treatment of deep venous thrombosis. Duplex imaging and Doppler color flow imaging have made the diagnosis of deep venous thrombosis relatively simple, painless, inexpensive, and definitive. These procedures have gained acceptance by both patients and physicians. Several risk factors have been identified that increase the chance of the development of deep venous thrombosis. These factors include a history of deep venous thrombosis, presence of a malignant process, increasing age, cigarette smoking, obesity, prolonged bed rest, and general anesthesia. The greater the number of risk factors, the more aggressive prophylaxis should be. Means of prophylaxis have improved, and surgeons now generally agree that some form of prophylaxis is required. Heparin and intermittent compression devices appear to be equally effective in preventing deep venous thrombosis. The addition of venous monitoring in high-risk patients permits immediate identification of the presence of deep venous thrombosis. During the last decade, the treatment of patients with deep venous thrombosis has changed little. Heparin followed by warfarin remains the treatment of choice. A small group of patients receive fibrinolytic therapy for deep venous thrombosis. Although the incidence of postoperative deep venous thrombosis has decreased during the last decade, it remains a significant complication.  相似文献   
157.
158.
The modulation of oxytocin (OT) receptors (OTRs) by estrogen was investigated in the ventromedial hypothalamus by in vitro receptor autoradiography. Treatment of ovariectomized and adrenalectomized rats with various doses of estradiol benzoate (EB) increased OTR binding not only in the ventromedial nuclei of the hypothalamus (VMN), but also in the area lateral to the nuclei (IVMN). After a single injection of EB, OTRs first were induced within the ventrolateral parts of the VMN, and only hours later they appeared in the IVMN. This is consistent with the interpretation that OTRs are first induced within the estrogen-sensitive neurons of the ventrolateral VMN and then are transported laterally out of the nuclei. Two additional experiments confirmed this interpretation. First, local infusion of a low dose (10 micrograms) of the neuronal transport inhibitor vinblastine blocked the appearance of OTRs in the IVMN but did not prevent the induction of OTRs by EB within the nuclei. Second, a knife cut placed lateral to the VMN prevented the spread of OTRs out of the nuclei. However, even after treatment with a high dose of EB (2 x 10 micrograms), progesterone (P) was required for a maximal extension of the area covered by OTRs. Thus, the OTR is an estrogen-induced neurotransmitter receptor that is transported to its site of action, the lateral ventromedial hypothalamus, where it is modulated by P and where estrogen-induced OT immunoreactivity is found.  相似文献   
159.
The apoenzyme of glutamate decarboxylase [enzyme without bound cofactor, pyridoxal 5'-phosphate (pyridoxal-P)] serves as a reservoir of inactive glutamate decarboxylase (GAD) that can be activated when additional GABA synthesis is required. We have investigated which of two molecular forms of GAD is present as apoenzyme in synaptosomes and in cortex, caudate nucleus, hippocampus, and cerebellum of rat brain. Endogenous glutamate apodecarboxylase (apoGAD) was labeled by incubating extracts of synaptosomes or punches of each region with 32P-pyridoxal-P, followed by reduction with NaBH4, to link covalently the 32P-pyridoxal-P to GAD. Proteins were separated by SDS-PAGE. Punches from all four brain regions and forebrain synaptosomes contained two forms of GAD with apparent Mrs of 63 and 65 kDa as identified by immunoblotting with four antiGAD sera. Punches and synaptosomes contained a major 32P-pyridoxal-P-labeled band with an apparent Mr of 63 kDa that was stained on immunoblots by the antiGAD serum 1440 and the monoclonal antibody GAD-6, and a minor labeled band at 65 kDa that was stained by the 1440, 6799, and K2 antisera. Synaptosomes contained remarkably few other strongly labeled proteins, but punches contained several other labeled bands. Three additional lines of evidence indicate that the labeled 63-kDa protein is apoGAD: (1) it was purified by immunoaffinity chromatography with the GAD-1 monoclonal antibody; (2) it yielded one major labeled peptide when digested with chymotrypsin, and that peptide appeared identical in peptide-mapping experiments to the labeled active-site peptide isolated from chromatographically prepared rat brain GAD; and (3) its labeling was selectively blocked by 4-deoxypyridoxine 5'-phosphate, a competitive inhibitor of the binding of pyridoxal-P to GAD.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
160.
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