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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
M. Wensing A. H. Penninks† S. L. Hefle‡ J. H. Akkerdaas§ R. van Ree§ S. J. Koppelman† C. A. F. M. Bruijnzeel-Koomen A. C. Knulst 《Clinical and experimental allergy》2002,32(12):1757-1762
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
992.
993.
M. Evans 《European journal of clinical microbiology & infectious diseases》2002,21(8):621-623
Ten oxacillin-sensitive Staphylococcus aureus strains were grown on agar containing four times their ciprofloxacin MIC to determine if exposure to ciprofloxacin would
increase their resistance to oxacillin. All strains grew on the ciprofloxacin-containing agar and subsequently grew on oxacillin-salt
agar. The geometric mean MICs for oxacillin increased one- to sixteen-fold and remained elevated after ten passages on antibiotic-free
agar. The mecA gene was not detected in any strain. There was no increase in oxacillin MICs when the bacteria were passaged on agar containing
four times their MIC of piperacillin/tazobactam. Exposure of oxacillin-sensitive strains of Staphylococcus aureus to ciprofloxacin may increase their MICs to oxacillin.
Electronic Publication 相似文献
994.
Regulations evolve and risks management becomes one of the biomedical engineers' preoccupations. Thus, risks are various, and consequently it is difficult to identify, to manage and to bring them under control. Furthermore, regulations exist for sectors like healthcare technology monitoring, but it is not the same thing for instance for the risks linked to the maintenance. Thus regulation in the sector of maintenance evolves and the decree of the 1st July law of health safety is going to modify the biomedical environment. The goal of this work is to study the tools and the methods of risks management that have been used for several years in the industrial field and to use them for some biomedical equipment like monitors or IV pumps. These methods adapted to these equipment will allow us to determine some appropriate rules of maintenance. 相似文献
995.
996.
D. Lothschütz M. Jennewein S. Pahl H.F. Lausberg A. Eichler W. Mutschler R.G. Hanselmann M. Oberringer 《Inflammation research》2002,51(8):416-422
OBJECTIVE AND DESIGN: Inflammatory and tumorous bronchi were screened in order to obtain new tumor relevant cytogenetic parameters. MATERIAL OR SUBJECTS: Bronchial cells of 32 patients were cultivated by standard cell culture procedures. METHODS: Tetraploidy and aneuploidy was determined by enumeration of chromosome 7 and 8 versus the number of centrosomes. The resulting data were correlated with histopathological data. RESULTS: Tetra- and aneuploidy of epithelial cells were detectable in 76% of tumor cell cultures, 75% of high grade inflammatory tissues and 40% of non- and low grade-inflammatory tissues. Additionally, we observed centrosome hyper-amplification and multipolar mitoses not only in the tumor but also in the early stages of inflammation. CONCLUSION: Inflammatory bronchi already show tumor-specific features and may consequently represent the preliminary genetic stage of cancer development in bronchi. 相似文献
997.
T. Berghmans F. Crokaert J. Sculier 《European journal of clinical microbiology & infectious diseases》2002,21(9):676-678
Vibrio cholerae was isolated from the blood cultures of a neutropenic patient treated with chemotherapy for non-small-cell lung cancer. Attempts
to isolate Vibrio spp. from a rectal swab and stool were unsuccessful. Piperacillin/tazobactam treatment resulted in eradication of the microorganism
from the patient's blood. Although Vibrio spp. have occasionally been the source of infection in immunocompromised patients, this report describes the first case of
non-0:1 Vibrio cholerae bacteremia in a neutropenic patient with a solid tumour.
Electronic Publication 相似文献
998.
A. Giacometti O. Cirioni G. Greganti A. Fineo R. Ghiselli M. Del Prete F. Mocchegiani B. Fileni F. Caselli E. Petrelli V. Saba G. Scalise 《European journal of clinical microbiology & infectious diseases》2002,21(7):553-556
The in vitro activities of povidone iodine, potassium peroxymonosulfate, and dimethyldidecylammonium chloride were investigated
against 379 nosocomial isolates of Staphylococcus aureus and Pseudomonas aeruginosa responsible for surgical wound infections in patients operated on between July 1995 and June 2001. Overall, the isolates
were inhibited by the antiseptics at concentrations below those used routinely. In spite of increasing resistance to the various
antibiotics used to treat surgical wound infections, no significant variation in the susceptibility to antiseptics was demonstrated
during this 6-year study.
Electronic Publication 相似文献
999.
1000.
Rapid adenosine release in the nucleus tractus solitarii during defence response in rats: real-time measurement in vivo 总被引:6,自引:3,他引:3
Nicholas Dale Alexander V. Gourine Enrique Llaudet David Bulmer Teresa Thomas† K. Michael Spyer 《The Journal of physiology》2002,544(1):149-160
We have measured the release of adenosine and inosine from the dorsal surface of the brainstem and from within the nucleus tractus solitarii (NTS) during the defence response evoked by hypothalamic stimulation in the anaesthetised rat. At the surface of the brainstem, only release of inosine was detected on hypothalamic defence area stimulation. This inosine signal was greatly reduced by addition of the ecto-5'-nucleotidase inhibitor α,β-methylene ADP (200 μM), suggesting that the inosine arose from adenosine that was produced in the extracellular space by the prior release of ATP. By placing a microelectrode biosensor into the NTS under stereotaxic control we have recorded release of adenosine within this nucleus. By contrast to the brainstem surface, a fast increase in adenosine, accompanied only by a much smaller change in inosine levels, was seen following stimulation of the hypothalamic defence area. The release of adenosine following hypothalamic stimulation was mainly confined to a narrow region of the NTS some 500 μm in length around the level of the obex. Interestingly the release of adenosine was depletable: when the defence reaction was evoked at short time intervals, much less adenosine was released on the second stimulus. Our novel techniques have given unprecedented real-time measurement and localisation of adenosine release in vivo and demonstrate that adenosine is released at the right time and in sufficient quantities to contribute to the cardiovascular components of the defence reaction. 相似文献