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931.
This paper presents 205 ca.ses of retinal vein occlusion (RVO) treated rr.wording t0 3 regi- mens and followed up periodically during the past 14 years. The clinical findings are analyz- ed. The effective rate of combined treatnwat with traditional Chinese medicine (TCM) and westeirn medicine in retinal branch vein oicclu- sion (RBVO) is 85.18To. 31.76'70 0f the patients with central retinal velin occlus.ion and 53.04% of tho相似文献   
932.
933.
STUDY OBJECTIVE--The aim was to examine if there is an effect of fathers' age and of birth order on the occurrence of congenital heart disease. DESIGN--This was a hospital based case-referent study including use of birth defects surveillance data. SUBJECTS--Subjects were 497 cases of congenital heart disease aged between 3 months and 5 years, born in Beijing and Hebei Province, China; 6222 children without congenital heart disease serve as reference baseline. MEASUREMENTS AND MAIN RESULTS--With stratified analysis and logistic regression analyses, congenital heart disease was found to be associated with fathers' age less than 25 years (odds ratio 2.63), independent of mothers' age and of birth order. There was also evidence to show a higher birth order effect on the occurrence of congenital heart disease independent of parental ages. CONCLUSION--Higher birth order and fathers aged less than 25 years were both independently associated with some categories of congenital heart disease and with congenital heart disease overall.  相似文献   
934.
1. The proposal that monoamine oxidase (MAO) is a source of peroxide in thyroid hormone biosynthesis has been examined by use of isolated cultured human thyroid cells which retain the ability to secrete triiodothyronine (T3) in response to thyroid stimulating hormone (TSH). 2. The results demonstrated the presence of MAO A and B in human thyroid cells which oxidized 5-hydroxytryptamine and 2-phenylethylamine, respectively, and were selectively inhibited by the MAO inhibitors clorgyline and (-)-deprenyl. 3. Addition of propylthiouracil to the culture system induced a 61% reduction in TSH-stimulated T3 secretion, indicating that the bulk of such secretion apparently derives from de novo iodothyronine synthesis. 4. The MAO A and B substrate, tyramine, was ineffective in stimulating T3 secretion. 5. The selective MAO inhibitors, clorgyline and (-)-deprenyl, alone and in combination, and in the presence and absence of tyramine, failed to inhibit basal as well as TSH-stimulated T3 secretion in cultured human thyrocytes. 6. It is therefore apparent that even though thyroid MAO A and B enzyme reactions result in the generation of H2O2, this H2O2 does not seem to play a significant role in T3 biosynthesis.  相似文献   
935.
Marrow cells from ten healthy adult donors were cultured in plasma clot diffusion chambers implanted intraperitoneally into mice. Host animals were conditioned by two injections of phenylhydrazine and 600 cGy of x-rays. Cultures (5 X 10(4) cells/chamber) were continued for between 2 and 40 days and the chambers were retransplanted into new host animals every 5 days. Following termination of cultures, plasma clots were stained with benzidine-hematoxylin and analyzed microscopically. Erythroid, neutrophil, monocyte, eosinophil, megakaryocyte, mixed, undifferentiated, and fibroblastoid colonies were grown with neutrophil, erythroid, monocyte, and eosinophil colonies being the most frequent. A total of between 25 and 60 colonies was observed per chamber at any time point.  相似文献   
936.
937.
938.
Reversed siderophores act as antimalarial agents.   总被引:4,自引:0,他引:4       下载免费PDF全文
We describe here a family of biomimetic iron carriers that display high binding efficiency for ferric ions and favorable permeation properties across erythrocytic membranes. These carriers inhibit in vitro growth of Plasmodium falciparum by scavenging intracellular iron. The chemical features were realized by reproducing the iron-binding cavities of natural iron carriers (siderophores) and by systematic substitutions of their hydrophilic envelopes for more hydrophobic ones. In contrast to natural carriers, which participate in receptor-mediated iron uptake in cells and act as growth promoters, our synthetic carriers were designed to penetrate cellular membranes by diffusion, scavenge intracellular iron, and thereby act as growth inhibitors. Based on these properties we designate the compounds reversed siderophores and refer to the specific analogs of the natural ferrichrome as synthetic ferrichromes. The antimalarial activity of the synthetic ferrichromes correlated with their lipophilicity, and this antimalarial activity was averted when the chelators were applied as iron (III) complexes. The sites of synthetic ferrichrome action reside in the intraerythrocytic parasite and not in serum or on normal erythrocyte components. The agents were effective against all stages of parasite growth and against a variety of multidrug-resistant strains of P. falciparum. The most potent agent of this synthetic ferrichrome series, SF1-ileu, was not toxic to mammalian cells in culture and was 15-fold more potent and 20-fold faster acting than desferrioxamine. Taken in toto, these agents constitute a series of promising candidates for future use in malaria chemotherapy.  相似文献   
939.
940.
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