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21.
Characteristics of wheeze during histamine-induced airways obstruction in children with asthma.
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S. Rietveld E. H. Dooijes L. H. Rijssenbeek-Nouwens F. Smit P. J. Prins A. M. Kolk W. A. Everaerd 《Thorax》1995,50(2):143-148
BACKGROUND--An automated system has been developed for the detection of sound patterns suggestive of airways obstruction in long term recordings. The first step, presented here, was tracheal sound recording during histamine-induced airways obstruction. METHODS--The tracheal sounds of 29 children aged 8-19 years with asthma were recorded during airways obstruction caused by histamine inhalation using a system for continuous respiratory telemetry and computer analysis. Sound patterns were analysed, classified, and related to airways obstruction measured by lung function tests based on the forced expiratory volume in one second (FEV1). RESULTS--Five sound patterns were identified, one dominant sensitive and four specific to a fall in FEV1 of > 20%. The presence of at least one of three specific sound patterns during unforced respiration predicted a fall in FEV1 of > 20% in 87.5% of the subjects. The inspiratory and expiratory sound patterns were almost equally informative of airways obstruction. CONCLUSIONS--Wheezes can be differentiated with more precision than is currently accepted. Tracheal sound patterns are sensitive and specific predictors of histamine-induced airways obstruction. These patterns are neither invariably nor proportionally related to the results of lung function testing. However, they can be used for detection of airways obstruction on the basis of their presence or absence. 相似文献
22.
One-day-old broiler chicks were infected orally with spirochaetes isolated from cases of intestinal disorder in humans. Three different isolates were studied in an experiment of 22 days duration. No signs of clinical disease were observed; the infection did not cause changes in the concentration of carotenoids or in the activity of alkaline phosphatase in the serum. Spirochaetes were shed in the caecal faeces. At autopsy, no lesions were seen in the intestinal tracts of the birds. Large numbers of spirochaetes were present in the caecum of 30 to 100% of the infected birds; in a few birds small numbers of spirochaetes were observed in scrapings from the mucosa of the small intestine. On histological examination massive colonisation of the caecal mucosa was observed. Spirochaetes of two isolates had invaded the caecal mucosa and for one of these, they were found between enterocytes, but not below the basement membrane. The other isolate had produced gap-like lesions, subepithelial accumulations of spirochaetes and focal erosion. No signs of an inflammatory reaction were observed. 相似文献
23.
Leukoencephalopathy with swelling in children and adolescents: MRI patterns and differential diagnosis 总被引:7,自引:0,他引:7
M. S. van der Knaap J. Valk P. G. Barth L. M. E. Smit B. G. M. van Engelen P. Tortori Donati 《Neuroradiology》1995,37(8):679-686
In children, several neurological disorders are characterised by spongiform leukoencephalopathy. MRI of the brain typically shows white matter swelling, but does not enable differentiation of the various underlying disorders. The aim of this article is optimisation of the diagnostic value of MRI in leukoencephalopathy accompanied by swelling. MRI-based inclusion criteria were met by 20 patients in our database. The images were analysed using a detailed scoring list. In 13 of the 20 patients the clinical diagnosis was known (11 definite and 2 probable diagnoses). Characteristic MRI abnormalities could be defined in these patients. Of the 7 patients without a diagnosis, 5 had identical MRI abnormalities: difuse hemisphere swelling and typical cysts in frontoparietal subcortical white matter and the tips of the temporal lobes. The clinical picture was also similar in these patients, suggesting a similar disease. 相似文献
24.
Xander Smit Johan W van Neck Menno J Ebeli Steven E R Hovius 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2004,38(6):321-325
Walking track analysis is a widely accepted technique for functional evaluation after sciatic nerve repair in rats, but it is labour-intensive. In 2000, Bervar described a time-saving digitised static footprint analysis. In that study there were good correlations between the traditional sciatic function index (SFI) and the newly-developed static sciatic index (SSI) and static toe spread factor (TSF), respectively. Despite promising results, static footprint analysis is still not widely used. The present study was designed to validate it. After transection of the sciatic nerve, end-to-end repair was assessed using video recorded dynamic and static footprints in 45 Wistar rats. We found an even better correlation between the SFI and both the SSI and the static TSF. In conclusion, static footprint analysis is a time-saving and easy technique for accurate functional assessment of peripheral nerve regeneration in rats. 相似文献
25.
26.
de Vrijer B Snijders MP Troostwijk AL Thé S Iding RJ Friese S Smit DA Schierbeek JM Brandts H van Kempen PJ van Buuren I Monza G 《Maturitas》2000,34(1):47-55
OBJECTIVE: To examine the efficacy and tolerability of a new matrix patch delivering estradiol (E2 Matrix) at doses of 0.05 and 0.10 mg per day (Estraderm MX 50, 100) in the treatment of moderate to severe postmenopausal symptoms. METHODS: A total of 254 postmenopausal women were randomized to receive treatment with E2 Matrix 0.10 mg (N = 86), E2 Matrix 0.05 mg (N = 82), or placebo (N = 86) in a double-blind, double-dummy fashion for a period of 12 weeks continuously. Patches were applied twice weekly to the buttocks with each patient wearing two patches at all times. The primary efficacy criterion was the difference from baseline of the mean number of moderate to severe hot flushes per 24 h during the last 2 weeks of treatment. Other efficacy variables included reduction in hot flushes at 4 and 8 weeks, reduction in daytime flushing and night sweats, and Kupperman Index at 4, 8, and 12 weeks. RESULTS: E2 Matrix 0.10 and 0.05 mg were both significantly superior to placebo in reducing hot flushes per 24 h after 4, 8, and 12 weeks of treatment (P < 0.001). Also, for all other efficacy parameters studied, both dosage strengths of E2 Matrix were statistically significantly superior to placebo at all time points (P < 0.001). Local tolerability was good in both groups. A slight increase in estrogen related adverse effects (breast tenderness, leukorrhoea) was seen with the 0.10 mg patch. Adhesion of patches and compliance were good. Overall systemic tolerability was good in both treated groups. However, a 4.8% overall incidence of endometrial hyperplasia was observed in patients with an intact uterus. CONCLUSIONS: This new matrix patch offers an effective and well tolerated dosage form for delivery of 0.05 and 0.1 mg estradiol per day. It may be particularly suitable for those women who experience local sensitivity to alcohol-containing systems. In light of the observed hyperplasia after treatment in five patients, estrogen therapy should as yet be supplemented monthly with a progestogen in women with an intact uterus. 相似文献
27.
Schwartz S Kent WJ Smit A Zhang Z Baertsch R Hardison RC Haussler D Miller W 《Genome research》2003,13(1):103-107
The Mouse Genome Analysis Consortium aligned the human and mouse genome sequences for a variety of purposes, using alignment programs that suited the various needs. For investigating issues regarding genome evolution, a particularly sensitive method was needed to permit alignment of a large proportion of the neutrally evolving regions. We selected a program called BLASTZ, an independent implementation of the Gapped BLAST algorithm specifically designed for aligning two long genomic sequences. BLASTZ was subsequently modified, both to attain efficiency adequate for aligning entire mammalian genomes and to increase its sensitivity. This work describes BLASTZ, its modifications, the hardware environment on which we run it, and several empirical studies to validate its results. 相似文献
28.
Functionally active complement proteins C6 and C7 detected in C6- and C7-deficient individuals 总被引:4,自引:2,他引:4
R. WÜRZNER A. ORREN P. POTTER B. P. MORGAN D. PONARD P. SPTH M. BRAI M. SCHULZE L. HAPPE O. G
TZE 《Clinical and experimental immunology》1991,83(3):430-437
Two sensitive sandwich ELISAs based on monoclonal antibodies directed to native C6 and C7 allowed the detection and quantitation of these complement proteins in 20 out of 37 serum samples from individuals who had previously been classified as deficient in these proteins as assessed by immunochemical and/or functional assays. Furthermore, serum from four C6-deficient and one combined C6-/C7-deficient individual showed an increase in the terminal complement complex (TCC) and a decrease in native C6 and C7 after complement activation as assayed by specific ELISAs. Despite their (incomplete) deficiencies, these individuals therefore possess functionally active terminal complement proteins with respect to their ability to generate the TCC. As these individuals have no history of a susceptibility to neisserial infections, even low concentrations of functionally active C6 and C7 may provide sufficient protection against those micro-organisms whose destruction requires TCC formation. 相似文献
29.
Bilateral simultaneous tubal sextuplets: pregnancy after in-vitro fertilization--embryo transfer following salpingectomy 总被引:2,自引:1,他引:2
The presence of a damaged tube has been suggested in recent studies to have
a negative effect on in-vitro fertilization (IVF) outcome. Performing
bilateral salpingectomy prior to IVF to maximize pregnancy rates may also
result in unnecessary surgery. This case is also an example of the
occurrence of interstitial pregnancy after salpingectomy. This unusual type
of ectopic pregnancy must be kept in mind when evaluating a patient
suspected of a possible early abnormal gestation after assisted
reproductive technolologies.
相似文献
30.
Annika S Smit Paul A T M Eling Maria T Hopman Anton M L Coenen 《International journal of psychophysiology》2005,57(3):211-217
Both physical and mental effort are thought to affect vigilance. Mental effort is known for its vigilance declining effects, but the effects of physical effort are less clear. This study investigated whether these two forms of effort affect the EEG and subjective alertness differently. Participants performed a physical task and were subsequently presented with a mental task, or vice versa. Mental effort decreased subjective alertness and increased theta power in the EEG. Both results suggest a vigilance decline. Physical effort, however, increased subjective alertness and alpha and beta1 power in the EEG. These findings point towards an increase in vigilance. Beta2 power was reduced after physical effort, which may reflect a decrease in active cognitive processing. No transfer effects were found between the effort conditions, suggesting that the effects of mental and physical effort are distinct. It is concluded that mental effort decreases vigilance, whereas physical effort increases vigilance without improving subsequent task performance. 相似文献