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991.
992.
This paper describes performance and results of a collaborative study in which the solid-phase enzyme immunoassay was tested in order to determine specific IgE under practical conditions. All titres of specific IgE can be differentiated in a reproducible way with high significance.  相似文献   
993.
994.
Radioreceptor assay (RRA) was used to evaluate serum antimuscarinic activity in 10 healthy volunteers after a single dose of scopolamine hydrobromide (ScHBr) solution, 0.02 mg/kg, by a new oral administration method. Cardiac, antisialogogue, and subjective effects of the drug were also recorded. Although clinically useful antisialogogue and sedative effects were obtained 40 to 60 minutes after the administration of ScHBr, no reliable antimuscarinic activity was evaluated in serum samples for up to 3 hours. Clinically useful sedative and antisialogogue effects can be reached by gastrointestinal absorption of ScHBr solution.  相似文献   
995.
The radiological appearance of mostly broad-based polyps in the rectosigmoid was studied in 35 patients. In all patients the diagnosis was histologically confirmed after surgical treatment. Conclusions on the histological tumour status could not be drawn either from surface structure, broadness of base and retraction of base, or from the base/height ratio. Stenosing growth, however, was seen relatively more often with carcinomas than with benign lesions. The discovery and identification of five carcinomas having a size of up to 2 cm illustrates the need for complete removal and histological processing of even seemingly negligible residues of polypous processes in the rectosigmoid.  相似文献   
996.
Whole sympathetic superior cervical ganglia of 14- and 15-day-old rat embryos were cultured in a collagen gel medium for 24 h with or without explants of heart atrium from the same animals or from newborn rats. The extent of nerve fibre outgrowth was estimated by counting the number of nerve fibres crossing each arc of a sector drawn in the microscope ocular. Only few nerve fibres extended from the ganglia of the 14-day-old embryos cultured in the pure control medium. Addition of exogenous nerve growth factor did not stimulate the poor growth. While the growth of nerve fibres in the presence of atrium explants of newborn rats did not significantly differ from that in cultures without any target tissue, the presence of atrium explants of the same, 14-day-old, embryo resulted in clearly enhanced fibre outgrowth from the ganglia, which was inhibited by antiserum to the nerve growth factor. The ganglia of 15-day-old embryos cultured without target tissue in the control medium produced only sparse fibre outgrowth which was excessively increased by exogenous nerve growth factor. Coculture with atrium explants of 15-day-old embryos or newborn rats produced an increased overall nerve fibre growth, as well as predominance of those fibres growing toward the target tissue. The growth-promoting effect of the atrium of 15-day-old embryos was only partially prevented by antiserum to the nerve growth factor, while that elicited by newborn rat atrium was totally inhibited.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
997.
998.
A R?ed 《Neuropharmacology》1989,28(8):765-773
N-Ethyl-maleimide (NEM, 2.5 x 10(-5) M) inhibited the compound action potential of the phrenic nerve and increased the spontaneous release of transmitter from the nerve terminals, recorded as miniature endplate potentials. The first effect was the cause of a blockade of the phrenic nerve diaphragm preparation, during indirect stimulation. The left phrenic nerve was more susceptible to inhibition than the right. An increase of the threshold was observed during the progression of the inhibition. The inhibition was not use-dependent and there was no synergistic interaction with the local anaesthetic drug, tetracaine. The inhibition was partly antagonized by di-thio-threitol (3.0 x 10(-3) M). The increase of spontaneous release of transmitter was not accompanied by an increase of the stimulus-evoked release since the amplitude of the endplate potential was not increased and partial inhibition caused by d-tubocurarine or magnesium chloride was not antagonized. When the concentration of NEM was increased to 2.75 x 10(-4) M, the directly-elicited twitches were inhibited, and the baseline tension was increased. This increase of tension was slightly reduced in a preparation depolarized with potassium chloride; a small depolarization could partly explain this effect. It was not reduced by dantrolene or in a calcium-free solution. The inhibition of the twitch and the increased baseline tension (probably a rigor) might be caused by a reduced sensitivity of the contractile proteins for calcium ions and an inhibition of the myosin ATPase activity, respectively.  相似文献   
999.
A peculiar hereditary corneal disease seen in one pedigree is presented. The disease manifests itself as transient attacks of kerato-endotheliitis. These attacks last from a few days to some weeks. Clinically, corneal oedema and endothelial guttata-like changes with very slight anterior chamber reaction can be seen; after many attacks there may be permanent opacities in the stroma. Endothelial specular photography during an attack reveals dramatic changes: large black nonreflecting areas between quite normal-looking hexagonal cells. Also between the attacks and among family members who have no clinical corneal disease, changes in the endothelium: black spots in the centres of endothelial cells and marked pleomorphism, are to be seen. Among the family members a high incidence of collagen diseases was found.  相似文献   
1000.
In 6 patients with medicamentously therapy-refractory tachycardias (3 times auricular flutter/auricular fibrillation with very rapid atrioventricular conduction, once focal atrial tachycardia, once paroxysmal atrioventricular reentry tachycardia, once recurrent ventricular tachycardia on the basis of an interventricular reentry) percutaneous transvenous catheter ablations of the atrioventricular conduction region (bundle of His ablation, 5 cases) and the right Tawara branch (1 case), respectively, were performed. During a follow-up period of 2-26 months (on an average 10.5 +/- 8.0 months) a permanent total block in 4 cases could be obtained (3 times AV-block III. once complete right bundle branch block). In two other patients the total AV block receded to the AV block I. and II. respectively, within 2 and 8 days, respectively; in the first case the AV node reentry tachycardias were no more to be evoked, in the second case a tolerable ventricular frequency was the result during the auricular flutter recidivations. In all patients treated by means of catheter ablation after the intervention an impressive improvement of the clinical symptomatology developed. Due to possible complication and the dependence upon the pacemaker of the patients concerned which is to be expected the indication to the ablation should be made only after the exhaustion of all medicamentous possibilities and taking into consideration other electric therapy methods.  相似文献   
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