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11.
The turnover rates of adrenaline in the medial preoptic area and mediobasal hypothalamus, areas which, respectively, include the cell bodies and terminals of luteinizing hormone-releasing hormone neurons, have been measured in female rats on pro-oestrus, the day of the preovulatory surge of luteinizing hormone, and on dioestrus, the preceding day. A rise in the rate of turnover was found in the medial preoptic area coinciding with the surge of luteinizing hormone in the late afternoon of pro-oestrus; the rate of turnover at this time was higher than at the same time on dioestrus. No changes in turnover rate were found in the mediobasal hypothalamus within either of these days.The results indicate that the adrenaline-containing projections to the preoptic area may be actively involved in the production of the spontaneous preovulatory surge of luteinizing hormone in rats. 相似文献
12.
In a study of 70 patients with asthma, rhinitis, and eczema, those giving a definite history of allergic reactions to egg more frequently showed positive skin tests to egg extracts (p = less than 0.003), the wheal diameters of which were significantly larger (p = less than 0.01) than in patients with only a possible or no such history. Patients with a definite history of egg allergy had significantly higher levels of specific IgE antibody against egg yolk, egg white, and allantoic fluid than patients in the other two groups (p = less than 0.005). Seven patients, all of whom had given a definite history of allergy to egg, were found to have positive skin prick tests to influenza vaccine, at the concentration used in medical practice. Two of these patients had previously been given influenza vaccine and both had developed adverse reactions. Of the 22 patients giving a definite history of allergy to egg, the 7 (35 per cent) with positive skin tests to influenza vaccine had significantly larger skin tests and higher levels of specific IgE antibody to the egg extracts than the group as a whole (p = less than 0.001). Allergic reactions to influenza vaccine are likely to occur in patients who have a definite history of allergy to egg and large skin prick test reactions or high levels of specific IgE antibody to egg extracts. Those at risk can best be identified by skin prick testing with egg extracts and undiluted influenza vaccine. 相似文献
13.
Mario Geller M.D. Dennis K. Flaherty Ph.D. Helen A. Dickie M.D. Charles E. Reed M.D. 《The Journal of allergy and clinical immunology》1977,59(6):445-448
Each of 5 patients with acute nitrofurantoin pleuropulmonary reactions had profound lymphopenia and 4 had eosinophilia developing early in the clinical course after the drug was withdrawn. The 2 patients tested had only one third of the normal numbers of E rosettes (T lymphocytes) in the peripheral blood during recovery. Lymphoblastic transformation tests with purified nitrofurantoin were done in 3 patients and all of them were negative; responses to phytohemagglutinin, concanavalin A, and pokeweed were decreased but still normal. The diagnosis of various nitrofurantoin hypersensitivity reactions relies on clinical data. The mechanisms of these reactions presently remain unclear. 相似文献
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16.
P C Atkins P M Bedard B Zweiman J Dyer M A Kaliner 《The Journal of allergy and clinical immunology》1984,73(3):341-347
In order to delineate parameters that might discriminate between allergic subjects who develop R or R-P symptoms during natural antigen exposure, 26 subjects allergic to grass or ragweed pollen were classified into R or R-P groups, and then the antigen sensitivity and degree of in vivo mediator release were compared. Antigen-skin sensitivity was quantitated by dilutional skin-test titration, and bronchial sensitivity was quantitated by the amount of inhaled antigen required to receive the FEV1 by 20%. Mediator release was determined by measuring the amount of histamine that was released into skin chambers during antigen incubation and the rise in plasma histamine and serum NCA during antigen-induced bronchospasm. Compared to the 13 R subjects, the 13 R-P subjects were: (1) more sensitive to antigen by both skin-test and inhalation challenge, (2) responded to inhalation of antigen with a greater fall in FEV1 and a greater rise in serum NCA and plasma histamine, and (3) released more histamine into skin chambers after antigen incubation. Even when R and R-P subjects were matched by comparing only subjects with equal skin sensitivity to antigen, greater increases in serum NCA and plasma histamine occurred after inhalation of antigen in the R-P subjects. These data are consistent with the hypothesis that allergic rhinitis subjects who develop pulmonary symptoms during natural pollen exposure are more sensitive to antigen and release more mediators in response to antigen administration. It is therefore possible that the degree of mediator release may be an important factor in determining the pattern of clinical responses to antigen exposure. 相似文献
17.
W C Light R E Reisman M Shimizu C E Arbesman 《The Journal of allergy and clinical immunology》1977,59(5):391-397
Fifteen patients were studied who had unusual reactions following insect stings. These included serum sickness, neurologic disease, renal disease, and delayed hypersensitivity-type reactions. The clinical features are briefly outlined. Measurements were made of serum venom-specific IgE and IgG antibodies. These antibodies were present in some patients and in these instances suggested an immunologic pathogenesis for the reactions. Alternative etiologies for the unusual reactions are also discussed. 相似文献
18.
The effect of adrenergic and cholinergic drugs on short incubation “active” E rosette formation was studied in 19 patients with bronchial asthma and 17 healthy controls. Both groups had an equal absolute number of baseline “active” E rosettes, but the asthmatics demonstrated a higher percent baseline value. The beta adrenergic drug isoproterenol (10?3 M) inhibited the formation of “active” E rosettes in asthmatics by only 18.0% as compared to a 60.8% inhibition in the control group. Carbamylcholine (10?5 M) a cholinergic agonist, also showed a lower than normal response in asthmatics, 34.3% enhancement of “active” E rosetting compared to a 52.4% enhancement in the controls. The alpha adrenergic agent phenylephrine (10?5 M) exhibited equal enhancing effects in both groups, 34.2% in the asthmatics and 36.5% in the controls. Isoproterenol (10?3 M) had a minimal effect on inhibition of long incubation “total” E rosettes in both groups studied. The beta adrenergic abnormality conforms to the beta blockade theory of asthma of Szentivanyi. The cholinergic abnormality is unexplained in view of the hyperresponsiveness of patients with asthma to cholinergic agents in vivo. Patients with bronchial asthma probably have an autonomic dysfunction that may play a role in the pathogenesis of their disease. 相似文献
19.
A graded dose assessment of the efficacy of beclomethasone dipropionate aerosol for severe chronic asthma. 总被引:7,自引:0,他引:7
J H Toogood N M Lefcoe D S Haines B Jennings N Errington L Baksh L Chuang 《The Journal of allergy and clinical immunology》1977,59(4):298-308
In a 26-wk double-blind controlled study of 34 patients whose asthma had been poorly controlled despite oral steroids, valuable clinical and pulmonary function improvement was derived by adding beclomethasone aerosol to the prednisone regimen. The amount of improvement correlated linearly with beclomethasone dosage over the range 200 to 1,600 microng/day. These patients required relatively high dosage. Success in achieving asymptomatic status was only 26% with the conventional 400 microng/day and 60% at 1,600 microng/day. Oropharyngeal candidiasis was also dose-related but did not prohibit the use of high-dosage beclomethasone. Respiratory infections, physical signs, blood glucose, and electrolytes were unaffected by the drug. A dose-related suppression of cortisol secretion was demonstrated, but about 1/4 of the group had normal plasma cortisol even at 1,600 microng/day plus the oral prednisone. An individualized risk-benefit assessment seems a better basis for choosing an optimal beclomethasone regimen for each patient than adherence to a conventionalized fixed dosage of 400 microng/day. This requires definition of: (1) a specific goal of treatment in the individual patient and the beclomethasone dosage required to achieve it; (2) the adrenocortical functional response of that particular patient to the desired dose of beclomethasone; and (3) the presence and degree of any dose-limiting constraints such as preexisting complications of steroid use. 相似文献
20.
R E Ruffin J D Fitzgerald A S Rebuck 《The Journal of allergy and clinical immunology》1977,59(2):136-141
The effects of the beta 2-adrenergic agonist, salbutamol, 200 mug, and the cholinergic antagonist, Sch 1000, 40 mug, have been compared in 25 asthmatic patients using a single dose, double-blind, crossover trial design. Salbutamol aerosol produces a greater degree of bronchodilatation than Sch 1000 aerosol during the initial three hours following drug administration. There is no significant difference in the bronchodilator effects of the two drugs in the interval four to eight hours after drug administration. Nonatopic patients showed less difference in bronchodilator response to each of the two drugs than atopic patients. Neither drug showed any significant adverse effect on blood pressure, pulse rate, or electrocardiogram. In six asthmatic patients the effect of the combination of salbutamol, 200 mug, and Sch 1000, 40 mug, was evaluated. The combination produced a longer duration of bronchodilatation than either drug alone when compared to placebo. 相似文献