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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
L. van den Bemt M. P. de Vries L. van Knapen M. Jansen M. Goossens J. W. M. Muris C. P. van Schayck 《Clinical and experimental allergy》2006,36(2):233-237
BACKGROUND: Exposure to a high level of house dust mite allergens (HDMAs) is considered as a risk factor for HDM sensitization and development of asthma in genetically disposed people. Mattresses are one of the most important sources of HDMA in people's living environment. OBJECTIVE: The aim of this study was to evaluate the association between mattress characteristics and HDMA concentrations on mattresses. METHODS: Dust samples of mattress surfaces were taken to evaluate the level of Der p 1 allergen. All participants filled in a questionnaire about the type of mattress, the type of covering (upper layer) of the mattress, dwelling characteristics and cleaning habits. Humidity and temperature of the bedroom were measured at the time of dust sampling. RESULTS: One hundred and sixty-eight questionnaires were filled in. Synthetic upper layer of the mattress was associated with a higher level of Der p 1 compared with cotton upper layer (2.6 vs. 0.8 microg/g Der p 1). Moreover, higher relative humidity (RH) was associated with significant higher concentrations and density of Der p 1. CONCLUSIONS: Two factors were associated with lower levels of Der p 1 found on mattresses, namely: a cotton upper layer of the mattress compared with a layer of synthetic material and lower RH at the time of sampling. As far as we know, the association between type of upper layer and concentration of Der p 1 has not been described before and could lead to the formulation of practical advices in order to reduce HDMA concentrations on mattresses. 相似文献
992.
993.
Effects of halothane on spinal dorsal horn WDR(wide dynamic range) neuronal activity in cats 总被引:1,自引:0,他引:1
H Nagasaka S Nakamura T Genda T Miyazaki K Aikawa N Matsumoto I Matsumoto T Hori I Sato 《Masui. The Japanese journal of anesthesiology》1991,40(7):1096-1101
The effects of halothane (0.2%, 0.5%, and 1.0%) on the spinal dorsal horn wide dynamic range (WDR) neuronal activity was studied in either spinal cord intact or spinal transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind foot pads of intact or decerebrate, spinal cord transected (L 1-2) cats. When 10 micrograms of bradykinin was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cat, all of 7 WDR neurons gave excitatory responses which were not depressed by 0.2% and 0.5% halothane but were depressed significantly by 1.0%. On the other hand, when the injection of 10 micrograms of bradykinin into the femoral artery ipsilateral to the recording site was used in the intact cat, 7 of 14 WDR neurons (50%) gave excitatory responses, which were not depressed by 0.2% halothane but were significantly depressed by 0.5% and 1.0% halothane, and 7 of 14 WDR neurons (50%) gave inhibitory responses, which were significantly depressed by 0.2%, 0.5%, and 1.0% halothane. We have found that halothane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by bradykinin injection. 相似文献
994.
David L. Healey B.D.S. Nicholas P. Chandler B.D.S. F.D.S. F.F.D. 《The Journal of prosthetic dentistry》1991,66(6):727-729
Experiments were performed to determine the effect of pin channel preparation with standard and reduction speed handpieces, and pin seating by hand and with motor drive. The greatest retention was achieved by preparation with a standard handpiece at 6000 rpm, and manual pin placement with a hand driver. The most consistent retention values were achieved using the reduction handpiece. All preparation and placement combinations examined produced a clinically acceptable result. 相似文献
995.
P Toulon J F Vitoux J N Fiessinger D Sicard M Aiach 《Blood coagulation & fibrinolysis》1991,2(3):435-439
In human plasma, heparin cofactor II (HCII) is a thrombin inhibitor which displays similarities with antithrombin III (ATIII). As previously reported for hereditary ATIII deficiency, cases of recurrent thrombosis were reported in patients with hereditary HCII deficiency. Here, plasma HCII activity was studied in 372 patients with a history of thrombosis, classified according to their anticoagulant therapy. The mean plasma HCII level was significantly higher in patients with acute deep vein thrombosis (DVT) under heparin therapy than in patients with a history of thrombosis, who were studied more than 3 months after the acute event, and were either on, or had been on, oral anticoagulant therapy. HCII and fibrinogen were significantly correlated in all three groups of patients. These results were strengthened by those of a follow-up study in 23 patients with acute DVT. Changes in plasma HCII activity paralleled those of fibrinogen. This suggests that HCII might behave like an acute phase reactant in patients with thrombosis and that the measurement of its plasma level as a risk factor for thrombosis should be performed some time after the acute episode. In conclusion, the prevalence of HCII deficiency in patients with a history of thrombosis might have been underestimated in series which included patients with acute thrombosis. 相似文献
996.
J S Abramowicz S L Warsof D M Sherer D L Levy J R Woods 《Journal of ultrasound in medicine》1991,10(6):337-339
A prospective blinded study was performed on 191 high-risk patients with pregnancies ranging from 25 to 42 weeks gestation to investigate the value of a single Doppler analysis of the umbilical artery blood flow waveform (systolic-to-diastolic ratio, S/D) for predicting poor perinatal outcome. This was defined as the presence of heavy meconium, delivery of a growth-retarded infant, an umbilical cord arterial pH less than 7.2, or a 5-minute Apgar score less than 7. The interval between Doppler examination and delivery ranged from 12 hours to 15 weeks. No clinical data were available to the examiner performing the Doppler study. Moreover, the Doppler measurements were unknown to the attending physicians. The sensitivity, specificity, and positive and negative predictive values of the Doppler study in predicting outcome were 30.4%, 92.9%, 36.8%, and 92.6%, respectively, with an adverse outcome prevalence of 12%. These results indicate that a single random S/D ratio from the umbilical artery is not an adequate screening test for the risk of perinatal complications. 相似文献
997.
S J Graafsma H Wollersheim H T Droste M A ten Dam L J van Tits J Reyenga J F Rodrigues de Miranda T Thien 《Clinical science (London, England : 1979)》1991,80(4):325-331
1. alpha 2-Adrenoceptors on platelet membranes and beta 2-adrenoceptors on lymphocytes were studied in 24 patients with primary Raynaud's phenomenon and in 24 age- and sex-matched control subjects. In two subgroups, a standardized mental arithmetic test and a finger-cooling test were performed. 2. Baseline blood pressure, heart rate and forearm blood flow did not differ between the two groups. 3. Baseline skin microcirculation (laser Doppler flux) was decreased in primary Raynaud's phenomenon (19 +/- 15 arbitrary units) compared with control subjects (33 +/- 14 arbitrary units) (P less than 0.01). 4. Baseline plasma noradrenaline concentration (2.00 +/- 1.44 versus 1.16 +/- 0.36 nmol/l) and alpha 2-adrenoceptor density (301 +/- 119 versus 210 +/- 82 fmol/mg) were increased in patients with primary Raynaud's phenomenon in comparison with the control subjects. The alpha 2-adrenoceptor density/beta 2-adrenoceptor density ratio in patients with primary Raynaud's phenomenon was, with a value of 0.37 +/- 0.04, higher than in the control subjects, where a value of 0.25 +/- 0.02 was measured (P less than 0.001). Plasma adrenaline concentration, beta 2-adrenoceptor density and the antagonist affinity to both receptor subtypes did not differ between both groups under baseline conditions. 5. Whereas during the finger-cooling test no differences were seen in the responses of the parameters measured, the mental arithmetic test induced an increase in laser Doppler flux in patients with primary Raynaud's phenomenon and a decrease in the control group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
L. S. Penrose 《European archives of psychiatry and clinical neuroscience》1991,240(6):315-324
Stylistic amendments to the original Penrose text have been made where necessary for further clarity 相似文献
999.
1000.