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991.
Accidental injury of medial rectus muscle in endoscopic surgery of ethmoidal sinus: case report and survey of literature 总被引:1,自引:0,他引:1
Schmidt T Thaller-Antlanger H Klopfer M 《Klinische Monatsbl?tter für Augenheilkunde》2002,219(1-2):59-63
BACKGROUND: Ophthalmologic complications of endoscopic sinus surgery are rare, consequences may be serious. PATIENTS: Two patients are presented who suffered lesions of the internal rectus muscles during endoscopic ethmoidectomy. The clinical picture of this rare complication resembles that of a paralysis of the medial rectus muscle. THERAPY AND COURSE: In one patient the very thinned medial rectus muscle was tucked in a first surgical step. In the second step the external rectus muscle was recessed. Fusion in primary gaze was possible. In the second patient surgery was planned, he died however. CONCLUSION: Because of the anatomy the medial rectus muscle is endangered in endoscopic ethmoidectomy. Considered to the frequency of this surgery the incidence however is rare. 相似文献
992.
993.
Receptor for advanced glycation endproducts: a multiligand receptor magnifying cell stress in diverse pathologic settings 总被引:14,自引:0,他引:14
Receptor for Advanced Glycation Endproducts (RAGE) is a member of the immunoglobulin superfamily of cell surface molecules capable of interacting with a broad spectrum of ligands, including advanced glycation endproducts (AGEs), amyloid fibrils, S100/calgranulins and amphoterin. The biology of RAGE is dictated by the accumulation of these ligands at pathologic sites, leading to upregulation of the receptor and sustained RAGE-dependent cell activation eventuating in cellular dysfunction. Although RAGE is not central to the initial pathogenesis of disorders in which it ultimately appears to be involved, such as diabetes, amyloidoses, inflammatory conditions and tumors (each of these conditions leading to accumulation of RAGE ligands), the receptor functions as a progression factor driving cellular dysfunction and exaggerating the host response towards tissue destruction, rather than restitution of homeostasis. These observations suggest that RAGE might represent a therapeutic target in a diverse group of seemingly unrelated disorders linked only by a multiligand receptor with an unusually wide and diverse repertoire of ligands, namely, RAGE. 相似文献
994.
Gastpar M Bonnet U Böning J Mann K Schmidt LG Soyka M Wetterling T Kielstein V Labriola D Croop R 《Journal of clinical psychopharmacology》2002,22(6):592-598
In a placebo-controlled, double-blind German multicenter study (seven sites) the efficacy of naltrexone as an adjunctive treatment in alcoholism to maintain abstinence was assessed for 12 weeks. A total of 171 detoxified patients (97.7% met the DSM-III-R criteria for alcohol dependence) were included. Patients had been abstinent for a mean of 19.5 +/- 9.4 days at study entry. Eighty-four and 87 patients were randomized to receive naltrexone (50 mg/day) and placebo, respectively. Each site was instructed to provide its usual psychosocial alcohol treatment program. The primary effectiveness measure was the time to first heavy drinking as derived from self-reports of drinking (timeline-follow-back method). Secondary effectiveness measures included time to first drink, amount of alcohol consumption, intensity of craving, severity of alcoholism problems, and liver enzymes. Thirty-three (38%) placebo patients and 28 (33%) naltrexone patients discontinued the study. At endpoint, 62% of the patients in each group did not have an episode of heavy drinking. Also, there were no significant differences between the study groups concerning secondary effectiveness measures as well as compliance and adverse clinical events--with the exception of the gamma-GT, which was significantly greater reduced in the naltrexone group throughout the study. Based upon an intention-to-treat population, this study confirms the safety but not the efficacy of naltrexone in prevention of alcohol relapse. Nevertheless, the question arises whether self-reports of drinking are more reliable than gamma-GT as a measure of recent alcohol consumption. 相似文献
995.
Schmidt MK Muslimatun S Schultink W West CE Hautvast JG 《European journal of clinical nutrition》2002,56(4):338-346
OBJECTIVE: To investigate whether supplementation with vitamin A together with iron of Indonesian pregnant women decreases morbidity and improves growth of their infants during the first year of life. DESIGN: Women from a rural area in West Java, Indonesia, were randomly assigned on an individual basis to double-blind supplementation once weekly from approximately 18 weeks of pregnancy until delivery. Supplementation comprised 120 mg iron and 500 microg folic acid with or without 4800 RE vitamin A. Their newborn infants were followed up during the first year of life: weight, length, morbidity and food intake were assessed monthly. RESULTS: Infants whose mothers had taken vitamin A supplements during pregnancy had similar weight, length, weight gain and growth as their counterparts during the follow-up period. The proportions of infants with reported symptoms of morbidity were similar in the vitamin A plus iron group and the iron group. In addition immunisation coverage and feeding mode did not differ between the groups. All infants were breast-fed, but exclusive breast-feeding rapidly declined at 4 months of age. Infants with serum retinol concentrations >0.70 micromol/l increased their weight and length more during the first 6 months of life and had higher weight-for-age Z-scores during the first year of life than infants with serum retinol concentrations 相似文献
996.
A cohort mortality and nested case-control study of French and Austrian talc workers 总被引:1,自引:1,他引:0 下载免费PDF全文
Wild P Leodolter K Réfrégier M Schmidt H Zidek T Haidinger G 《Occupational and environmental medicine》2002,59(2):98-105
Objectives: To study whether the mortality from non-malignant and malignant respiratory diseases of workers employed in French and Austrian talc mines and mills is related to their long term occupational exposure. 相似文献
997.
NO- and haem-independent activation of soluble guanylyl cyclase: molecular basis and cardiovascular implications of a new pharmacological principle 下载免费PDF全文
Stasch JP Schmidt P Alonso-Alija C Apeler H Dembowsky K Haerter M Heil M Minuth T Perzborn E Pleiss U Schramm M Schroeder W Schröder H Stahl E Steinke W Wunder F 《British journal of pharmacology》2002,136(5):773-783
1. Soluble guanylyl cyclase (sGC) is the only proven receptor for the ubiquitous biological messenger nitric oxide (NO) and is intimately involved in many signal transduction pathways, most notably in regulating vascular tone and platelet function. sGC is a heterodimeric (alpha/ss) protein that converts GTP to cyclic GMP; NO binds to its prosthetic haem group. Here, we report the discovery of a novel sGC activating compound, its interaction with a previously unrecognized regulatory site and its therapeutic implications. 2. Through a high-throughput screen we identified BAY 58-2667, an amino dicarboxylic acid which potently activates sGC in an NO-independent manner. In contrast to NO, YC-1 and BAY 41-2272, the sGC stimulators described recently, BAY 58-2667 activates the enzyme even after it has been oxidized by the sGC inhibitor ODQ or rendered haem deficient. 3. Binding studies with radiolabelled BAY 58-2667 show a high affinity site on the enzyme. 4. Using photoaffinity labelling studies we identified the amino acids 371 (alpha-subunit) and 231 - 310 (ss-subunit) as target regions for BAY 58-2667. 5. sGC activation by BAY 58-2667 results in an antiplatelet activity both in vitro and in vivo and a potent vasorelaxation which is not influenced by nitrate tolerance. 6. BAY 58-2667 shows a potent antihypertensive effect in conscious spontaneously hypertensive rats. In anaesthetized dogs the hemodynamic effects of BAY 58-2667 and GTN are very similar on the arterial and venous system. 7. This novel type of sGC activator is a valuable research tool and may offer a new approach for treating cardiovascular diseases. 相似文献
998.
van der Giet M Schmidt S Tölle M Jankowski J Schlüter H Zidek W Tepel M 《European journal of pharmacology》2002,448(2-3):207-213
The aim of the present study was to investigate the effects of Xp(5)X and Xp(6)X (X = guanosine (G) or adenosine (A); n = 5 and 6), which have been identified in human platelets, on coronary vascular tone. The activation of purinoceptors in rat coronary vasculature by Xp(5)X and Xp(6)X was evaluated by measuring their effects on perfusion pressure in the Langendorff perfused rat. Ap(5)X and Ap(6)X induced dose-dependent vasodilation that was due to P2Y(1) receptor activation, as evidenced by use of the selective P2Y(1) receptor antagonist 2'-deoxy-N(6)-methyl-adenosine 3',5'-diphosphate diammonium (MRS2179). Vasodilation was induced by NO release, as evidenced by inhibition of nitric oxide synthases (NO synthases) by N(G)-nitro-L-arginine methyl ester (L-NAME). The dose-dependent decrease in coronary perfusion pressure induced by Ap(5)X and Ap(6)X was converted to a dose-dependent increase in perfusion pressure after inhibition of NO synthases by L-NAME. After endothelium removal, the vasodilation elicited by Ap(5)X and Ap(6)X was converted to a vasoconstriction which could be inhibited by P2X receptor blockade. Ap(5)A, Ap(5)G, Ap(6)A and Ap(6)G are vasodilating or vasoconstricting nucleotides that activate P2Y(1) or P2X receptors depending on the status of the coronary vascular endothelium. 相似文献
999.
Matter H Kotsonis P Klingler O Strobel H Fröhlich LG Frey A Pfleiderer W Schmidt HH 《Journal of medicinal chemistry》2002,45(14):2923-2941
The family of homodimeric nitric oxide synthases (NOS I-III) catalyzes the generation of the cellular messenger nitric oxide (NO) by oxidation of the substrate L-arginine. The rational design of specific NOS inhibitors is of therapeutic interest in regulating pathological NO levels associated with sepsis, inflammatory, and neurodegenerative diseases. The cofactor (6R)-5,6,7,8-tetrahydrobiopterin (H(4)Bip) maximally activates all NOSs and stabilizes enzyme quaternary structure by promoting and stabilizing dimerization. Here, we describe the synthesis and three-dimensional (3D) quantitative structure-activity relationship (QSAR) analysis of 65 novel 4-amino- and 4-oxo-pteridines (antipterins) as inhibitors targeting the H(4)Bip binding site of the neuronal NOS isoform (NOS-I). The experimental binding modes for two inhibitors complexed with the related endothelial NO synthase (NOS-III) reveal requirements of biological affinity and form the basis for ligand alignment. Different alignment rules were derived by building other compounds accordingly using manual superposition or a genetic algorithm for flexible superposition. Those alignments led to 3D-QSAR models (comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA)), which were validated using leave-one-out cross-validation, multiple analyses with two and five randomly chosen cross-validation groups, perturbation of biological activities by randomization or progressive scrambling, and external prediction. An iterative realignment procedure based on rigid field fit was used to improve the consistency of the resulting partial least squares models. This led to consistent and highly predictive 3D-QSAR models with good correlation coefficients for both CoMFA and CoMSIA, which correspond to experimentally determined NOS-II and -III H(4)Bip binding site topologies as well as to the NOS-I homology model binding site in terms of steric, electrostatic, and hydrophobic complementarity. These models provide clear guidelines and accurate activity predictions for novel NOS-I inhibitors. 相似文献
1000.
The cyclipostins are a group of hormone-sensitive lipase inhibitors produced by a Streptomyces species. Having verticillate spore chains this strain exhibits significant differences to the known species of the former genus Streptoverticillium. Taxonomic studies and fermentation results are presented. 相似文献