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101.
BACKGROUND: Reduction of house dust mite allergens in the domestic environment can play an important part in reducing sensitization and in the amelioration of symptoms in atopic individuals. Chemical and physical methods have been tried with varied levels of success. The present paper presents a novel electrostatic way of destroying Der p 1, the major mite allergen. OBJECTIVE: To assess the efficacy of negative Trichel, negative continuous glow, positive pulse and positive continuous glow corona in destroying Der p 1. To determine whether ozone has any effect on the integrity of Der p 1 in the experimental conditions present. METHODS: A simple point-to-plane apparatus was used to irradiate samples of Der p 1 for periods of 1, 15, 30, 45, 60, 120, 180, 240 and 300 min. Controls were exposed to the atmosphere with no corona products present for the equivalent time. The effect of the corona by-product ozone was investigated alone by exposing samples of Der p 1 to molecular ozone for 60 min. Der p 1 concentration was quantified by two-site monoclonal antibody ELISA. RESULTS: High current negative glow resulted in a 67.37% reduction in Der p 1 concentration after 300 min compared with a 50.5% reduction from a low current Trichel regime. High current positive glow corona gave a reduction of 25.22% while a low current positive pulse corona caused a 13.72% reduction after 300 min. All these reductions were statistically significant (P < 0.05) compared with unexposed controls. Negative corona always gave greater percentage reductions in Der p 1 concentration for each time exposure investigated. The pattern of percentage reduction follows an exponential rise to maximum relationship in respect to time. Samples of Der p 1 were not affected by exposure to molecular ozone. CONCLUSION: These data indicate corona products to be a powerful new method of destroying Der p 1 allergen that is not dependent on the presence of the oxidizing corona product ozone. 相似文献
102.
103.
Posterior chamber intraocular lens implantation in the absence of posterior capsular support 总被引:1,自引:0,他引:1
Because of the high incidence and great variety of complications associated with anterior chamber intraocular lenses, we have developed a technique for the implantation of a posterior chamber intraocular lens in the absence of posterior capsular support. The posterior chamber IOL is placed in the ciliary sulcus by suturing the superior haptic to the iris and the inferior haptic to the sclera at the ciliary sulcus. We have used this technique successfully in both complicated extracapsular surgery and secondary intraocular lens implantation. 相似文献
104.
J. L. Morris 《Clinical and experimental pharmacology & physiology》1995,22(11):792-802
1. Neuropeptides are present in the majority of autonomic neurons projecting to blood vessels, where they are co-localized with non-peptide transmitters and sometimes with other peptides. 2. Neuropeptides are released from vasoconstrictor and vasodilator nerve terminals after high frequency stimulation (>2–5 Hz) with trains of impulses. 3. Neuropeptides can have potent post-synaptic effects on vascular tone, but often these effects are restricted to selected regions of the vasculature. 4. Post-synaptic effects of neuropeptides tend to be more slowly-developing and more long-lasting than those of non-peptide transmitters. 5. Autonomic vasoconstrictor and vasodilator responses often have multiple phases, with the faster phases being mediated by non-peptide transmitters and the slower phases mediated predominantly by one or more neuropeptides. 6. Some neuropeptides do not seem to have post-synaptic effects in a particular vascular bed, but can have presynaptic actions on neurotransmitter release. 7. Neuropeptides form an important component of the repertoire of neurotransmitters used by vascular autonomic neurons to regulate regional blood flow in response to a range of physiological stimuli. 相似文献
105.
H H Dayal M Brodwick R Morris T Baranowski N Trieff J A Harrison J R Lisse G A Ansari 《Annals of epidemiology》1992,2(3):213-230
An accident at an oil refinery in Texas City, Texas, released around 40,000 lb of hydrogen fluoride, exposing the community to the highly toxic and corrosive substance. A population-based epidemiologic study was conducted to evaluate the impact of the accident on the health of the community. Exposure assessment was done using a multipronged approach through a door-to-door survey of 10,811 individuals. A symptom survey resulting in 1994 completed interviews was conducted with a stratified random sample selected from the exposure study database. The sampling was balanced with respect to age, gender, and predisposition across the three ordinal exposure categories. The results show a strong dose relationship (P < 10(-4)) between the exposure and symptoms reported following the accident and 2 years later, most notably breathing and eye symptoms. However, substantial improvement in health was reported over the 2-year period regardless of the level of exposure. Problems of recall bias and behavioral sensitization are considered and it is recognized that the study may have overestimated the effect. It is also recognized that the study may not have completely unraveled the relative importance of exposure and host response in health outcome, since the two were probably conflated in the exposure measure. Nevertheless, the independence of predisposition and reported level of exposure, the magnitude of effect and its consistency, the unmistakable dose response, the large sample size, and the mutual corroboration of various findings make it difficult to dismiss the interpretation that the hydrofluoric acid exposure indeed caused health problems in the community that continued for at least 2 years after the accident. 相似文献
106.
Diana A. Lepore Kenneth R. Knight Surajit Bhattacharya Morris Ritz Sonia P. Robbins Peter Sieg Wayne A. Morrison Bernard McC. O'Brien 《Microsurgery》1994,15(10):685-692
The chief aim of this study was to maximize flap survival by counteracting the pathophysiological changes occurring during ischemia-reperfusion. Rabbit epigastric skin flaps given 21 hours of ischemia were infused intra-arterially with selected drugs at the start of reperfusion. Compared with control infused ischemic flaps, which had a 33% survival rate on day 7 post-ischemia, significant improvement was found with vasodilators nitrendipine (61%) and prostacyclin (65%) and the thrombolytic agent urokinase (65%); marginal improvement with the free radical scavenger desferrioxamine (53%); but no change with streptokinase (44%), heparin (21%), and ATP-MgCl2 (35%). A drug mixture comprising all of these agents except streptokinase and urokinase produced 87% survival, suggesting an additive effect. Biochemical assays on skin homogenates and blood implicated oxygen free radicals, neutrophil infiltration, and thromboxane in flap failure. These results imply that multiple factors are responsible for ischemic flap failure and that a mixture of drugs needs to be infused to counteract all of the detrimental changes. © 1994 Wiley-Liss, Inc. 相似文献
107.
H W Losken W M Morris P B Uys J W Earle P A Le Roux E Ackermann 《Suid-Afrikaanse tydskrif vir geneeskunde》1988,73(10):575-577
Trauma to the orbital region may result in fractures of the bony orbit, displacement of which gives rise to malposition of the eye and diplopia. If initial treatment is not feasible or is unsuccessful, later correction may be achieved by osteotomy or reduction and stabilisation of the bony fragments, often with bone grafts. Displaced medial or lateral canthi may need to be repositioned, where feasible in an overcorrected position. Where bone grafts are necessary, the skull is now favoured as the best donor site. 相似文献
108.
Two colorectal (HT29, LoVo) and one gastric (MKN45) human tumour cell lines were examined for their in vitro trophic response to human gastrin-17. MKN45 and HT29 responded by increased 75Se selenomethionine uptake to exogenous gastrin (139 +/- 5.5% and 123 +/- 3% of control values respectively) whereas LoVo showed no significant response to this hormone. When these same cell lines were grown as xenografts in nude mice, similar responses were seen to exogenously administered human gastrin-17 (10 micrograms mouse-1 day-1, subcutaneous injection). MKN45 xenografts showed a greater response to continuously administered gastrin (osmotic mini-pumps, (10 micrograms mouse-1 day-1) when compared to the same dose given via a subcutaneous bolus injection. The hormone-treated xenografts had a two-fold increase in tumour cross-sectional area and growth rate when compared to saline-treated controls. Dose-response studies revealed that 0.4 micrograms gastrin mouse-1 day-1 appeared to be the minimally effective dose. As gastric and colorectal tumour cells show a trophic response to gastrin, antagonists of the gastrin receptor may prevent this effect causing tumour stasis. The gastric tumour cell line, MKN45, is gastrin-responsive and would be an ideal model for screening potent receptor antagonists. 相似文献
109.
DQ beta restriction fragment patterns have been obtained from five DRw8 cell lines homozygous for the null DQ allele, DQWa. The enzymes Bgl II, Bam HI and Pvu II generate DQ beta patterns which are indistinguishable from those obtained from cell lines homozygous for DQw3.2. 相似文献
110.
AIMS: To determine if leucocyte volume distribution analysis (LVDA), obtained using a Coulter Counter Model S Plus IV, can be used to aid differentiation of chronic lymphoproliferative disorder (CLPD) subtypes. METHODS: Mean lymphocyte volume and lymphocyte distribution width were measured on each patient (n = 90) using a hard copy of an amplified LVDA histogram. The mean lymphocyte volume was taken as the mean of the values on either side of the peak at half maximum height. The lymphocyte distribution width was taken as the range of cell values between the two values used to calibrate the mean lymphocyte volume. A template showing typical histograms from commonly occurring CLPD was also produced on an acetate sheet. This was used to examine the histogram from each new patient to evaluate its usefulness as an alternative to the calculation of mean lymphocyte volume and lymphocyte distribution width. RESULTS: Mean lymphocyte volume and lymphocyte distribution width were significantly higher in B cell lymphocytic leukaemia of mixed cell type (B CLL/PL), B cell non-Hodgkin's lymphoma with peripheral blood spill, hairy cell leukaemia and T cell prolymphocytic leukaemia than in B cell chronic lymphocytic leukaemia (B CLL). The mean lymphocyte volume, but not the lymphocyte distribution width, was also significantly higher in T cell chronic lymphocytic leukaemia than in B CLL. The template gave an immediate preliminary indication of possible subtype(s) of disorder and could be used as an alternative to measurement of mean lymphocyte volume and lymphocyte distribution width. CONCLUSIONS: Electronic haematology analysers producing an LVDA provide a useful, cost effective cell sizing analysis which can aid the differentiation of subtypes of CLPD. 相似文献