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排序方式: 共有636条查询结果,搜索用时 15 毫秒
91.
L. TÓTH SAROLTA KARCSÚ MÁRIA POBERAI GY. SÁVAY 《Neuropathology and applied neurobiology》1981,7(5):399-410
Tóth L., Karcsú S., Poberai M. & Sávay Gy. (1981) Neuropathology and Applied Neurobiology 7, 399–410
A light and electron microscopic histochemical study on the mechanism of DFP-induced acute and subacute myopathy
The histochemical changes occuring in association with the development of acute and subacute myopathy have been studied in the rat diaphragm 30 min-48 h after a single i.p. injection of 1–82 mg/kg of the irreversible cholinesterase inhibitor organophosphate, diisopropylfluorophosphate (DFP). In addition to a considerable inhibition of the AChE activity of the motor end-plates, accumulation of ionic Ca2+ and an increase in neutral protease activity in the subjunctional sarcoplasm have been demonstrated. A temporal and causal relationship has been established between the histochemical changes and the development of the ultrastructural signs of myopathy. 相似文献
A light and electron microscopic histochemical study on the mechanism of DFP-induced acute and subacute myopathy
The histochemical changes occuring in association with the development of acute and subacute myopathy have been studied in the rat diaphragm 30 min-48 h after a single i.p. injection of 1–82 mg/kg of the irreversible cholinesterase inhibitor organophosphate, diisopropylfluorophosphate (DFP). In addition to a considerable inhibition of the AChE activity of the motor end-plates, accumulation of ionic Ca
92.
93.
M. TH. HAUMONTÉ 《Addiction (Abingdon, England)》1967,62(1-2):49-53
This study was undertaken on 50 male patients chosen at random among the 188 who came in the last 6 months. 相似文献
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96.
Autoantibodies and immunoglobulin allotypes in healthy North American Blacks of different age groups
TH. Ockhuizen J.P. Pandey G.M.P. Galbraith H.H. Fudenberg C.G. Hames 《Mechanisms of ageing and development》1982,19(2):103-111
A population of 291 healthy North American Black subjects of different ages was studied for immunoglobulin (Ig) allotypes and the prevalence of autoantibodies, to determine possible associations between Ig allotypes and age, autoantibodies and age, and Ig allotypes and autoantibodies. Indirect immunofluorescence was used to detect anti-gastric parietal cell, anti-smooth muscle, anti-thyroid microsomal, anti-nuclear, and anti-mitochondrial antibodies. The sera were typed for the Ig allotypes Gm(1, 2, 3, 5, 6, 13, 14, 17, and 21) and Km(1) with a hemagglutination-inhibition assay. A significant association between advanced age and an increased prevalence of anti-nuclear antibodies was observed in females. There was no significant association between Ig allotypes and the autoantibodies tested. The results suggest that Ig allotypes are not involved in the development of autoantibodies in healthy Blacks. 相似文献
97.
Acetylcarbocholine and acetylsilicocholine: Directly or indirectly acting cholinergic spasmogens? 总被引:1,自引:0,他引:1
P. TH. HENDERSON E. J. ARIËNS B. W. J. ELLENBROEK A. M. SIMONIS 《The Journal of pharmacy and pharmacology》1968,20(1):26-35
The cholinergic and anticholinergic actions of nitrogen-free isosteres of acetylcholine and benzilylcholine are described. Esters of two kinds of choline analogues, carbocholine and silicocholine, were used. The spasmogenic activity of acetylcarbocholine and acetylsilicocholine on the guinea-pig ileum was identified as an indirect cholinergic action, in contrast to the direct cholinergic action of furtrethonium and the mainly non-cholinergic action of barium ions. In addition to this indirect cholinergic action, both esters show a weak anticholinergic and a weak noncompetitive “papaverine-like” spasmolytic activity. The corresponding benzilyl esters, although without an onium group, are relatively potent anticholinergic compounds. 相似文献
98.
C. DACOU-VOUTETAKIS TH. THOMAIDIS E. ROMA A. KALPINI-MAVROU C. ECONOMOU-MAVROU 《Acta paediatrica (Oslo, Norway : 1992)》1975,64(5):773-776
ABSTRACT: Dacou-Voutetakis, C. Thomaidis, Th., Roma, E., Katpini-Mavrou, A. and Economou-Mavrou, C. (First Department of Paediatrics, Athens University, Greece). Systemic allergic reaction to initial insulin therapy in a juvenile diabetic. Enhanced blast transformation to insulin. Acta Paediatr Scand, 64: 773, 1975–A 14-year-old girl with recent onset of diabetes developed a severe systemic allergic reaction to beef-pork insulin on the third day of insulin therapy. The same reaction developed following the injection of pork insulin and monocomponent insulin. The patient was induced to tolerate pork insulin by systemic de-sensitization to this insulin over an interval of 6 days. Peripheral blood lymphocytes from the patient cultured in the presence of insulin responded by increased blast cell transformation, as compared with controls, who either had previously presented local allergic reactions to insulin or never had manifested insulin allergy. 相似文献
99.
Southwick FS; Howard TH; Holbrook T; Anderson DC; Stossel TP; Arnaout MA 《Blood》1989,73(7):1973-1979
Polymorphonuclear leukocytes (PMN) with a deficiency of the complement receptor type 3 (CR3) membrane glycoprotein family have impairments in the ability to adhere to surfaces as well as chemotactic and phagocytic defects, processes that require a functional contractile apparatus. PMN from the patient with neutrophil actin dysfunction (NAD) displayed similar functional characteristics to those with CR3 deficiency suggesting the two disorders may be the same disease. In order to evaluate the relationship between CR3 deficiency and actin assembly, actin filament assembly was measured in PMN from six previously reported homozygotes (two severe and four moderate CR3-deficient patients) as well as five heterozygotes for CR3 deficiency. PMN from all patients had normal unstimulated concentrations of F-actin and after exposure to the chemotactic peptide FMLP (5 x 10(-7) mol/L for 5 to 40 seconds at 25 degrees C) assembled actin normally. Pretreatment of normal PMN with concentrations of monoclonal anti-alpha CR3 antibody, capable of blocking PMN adherence, also failed to impair FMLP- induced actin filament assembly. CR3 glycoprotein expression was measured in PMNs from the mother, father, and older sister of the NAD patient (N Engl J Med 291:1093, 1974). Actin filament assembly was recently shown to be defective in PMNs from all three family members. The total concentrations of the alpha and beta CR3 subunits were below normal in PMN detergent extracts from the mother (25% of simultaneous controls) and older sister (56% of control). PMN surface expression of these two subunits was also found to be depressed (mother, 50%; older sister, 63% of control). These findings suggest these two NAD family members are heterozygote carriers for CR3 deficiency as well as NAD. Simultaneous studies of the father, however, demonstrated normal total concentrations of both the alpha and beta CR3 subunits (126% of controls) as well as normal surface expression of both subunits after phorbol myristate acetate stimulation and incubation at 37 degrees C (mean, 112% of controls) but slightly lower than normal levels after FMLP stimulation (mean, 83%). These findings indicate that CR3 deficiency generally is not associated with defective actin filament assembly and support the conclusion that NAD represents a unique kindred in which PMN actin function differs from previously reported genotypes of CR3 deficiency. 相似文献
100.
Jasgurpreet Singh Chohan Raman Kumar TH Bhatia Singh Sandeep Singh Shubham Sharma Jujhar Singh Mozammel Mia Danil Yurievich Pimenov Somnath Chattopadhyaya Shashi Prakash Dwivedi Wojciech Kaponek 《Materials》2020,13(22)
Despite several additive manufacturing techniques are commercially available in market, Fused Deposition Modeling (FDM) is increasingly used by researchers and engineers for new product development. FDM is an established process with a plethora of advantages, but the visible surface roughness (SR), being an intrinsic limitation, is major barrier against utilization of fabricated parts for practical applications. In the present study, the chemical finishing method, using vapour of acetone mixed with heated air, is being used. The combined impact of orientation angle, finishing temperature and finishing time has been studied using Taguchi and ANOVA, whereas multi-criteria optimization is performed using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The surface finish was highly responsive to increase in temperature while orientation angle of 0° yielded maximum strength; increase in finishing time led to weight gain of FDM parts. As the temperature increases, the percentage change in surface roughness increases as higher temperature assists the melt down process. On the other hand, anisotropic behaviour plays a major role during tensile testing. The Signal-to-noise (S/N) ratio plots, and ANOVA results indicated that surface finish is directly proportionate to finishing time because a longer exposure results in complete layer reflowing and settlement. 相似文献