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901.
Summary— Bupivacaine is the most widely used local anaesthetic in obstetrics for epidural analgesia. Nineteen women (mean age 26.9 ± 5.3 years) who underwent epidural analgesia during labour were included in this study. All parturients received a first injection of 21.8 ± 2.5 mg 0.25% plain bupivacaine. The following administrations were given on request: 0.25% concentration was used when cervix uteri was supple, and a 0.375% concentration when it was tonic. Blood samples were collected 5 min after the first injection and then every 30 min until delivery. At delivery blood samples were collected from the infant umbilical cord vein and from the arm vein of the mother. Bupivacaine was assayed by high pressure liquid chromatography. Serum data were analyzed for each patient using a non-compartmental model. Bupivacaine was rapidly detected in serum, and maximal concentration was reached between 5 and 35 min. Pharmacokinetic parameters were estimated in 17 women after the first injection: 87 ± 35 min for elimination half-life, 60 ± 19 L for apparent volume of distribution and 0.5 ± 0.3 L/min for plasmatic clearance. For a mean total duration of labour and total dose administered of respectively 222 ±115 min and 57.1 ± 28.7 mg, the mean value of the foeto-maternal ratio was 0.29 ±0.10. The infant maximal serum concentration was 0.26 μg/mL. No side effects were spontaneously reported by the parturients and all infants had an Apgar score of 10 at 5 min after the delivery. We confirm the fast systemic absorption and rapid elimination of bupivacaine which may be used without risk of acute toxicity both in mother and child, even when it is used in a 0.375% concentration.  相似文献   
902.
Caveolin-3 in muscular dystrophy   总被引:2,自引:0,他引:2  
The dystrophin-glycoprotein complex (DGC) serves as a link between cytoplasmic actin, the membrane and the extracellular matrix of striated muscle. Genetic defects in genes encoding a subset of DGC proteins result in muscular dystrophy and a secondary decrease in other DGC proteins. Caveolae are dynamic structures that have been implicated in a number of functions including endocytosis, potocytosis and signal transduction. Caveolin (VIP-21) is thought to play a structural role in the formation of non-clathrin-coated vesicles in a number of different cell types. Caveolin-3, or M-caveolin, was identified as a muscle- specific form of the caveolin family. We show that caveolin-3 co- purifies with dystrophin, and that a fraction of caveolin-3 is a dystrophin-associated protein. We isolated the gene for human caveolin- 3 and mapped it to chromosome 3p25. We determined the genomic organization of human caveolin-3 and devised a screening strategy to look for mutations in caveolin-3 in patients with muscular dystrophy. Of 82 patients screened, two nucleotide changes were found that resulted in amino acid substitutions (G55S and C71W); these changes were not seen in a control population. The amino acid changes map to a functionally important domain in caveolin-3, suggesting that these are not benign polymorphisms and instead are disease-causing mutations.   相似文献   
903.
904.
BACKGROUND: The combination of omeprazole with amoxycillin or clarithromycin is used as treatment against Helicobacter pylori. It seems likely that the antibacterial activity of the antibiotic may be improved by increasing gastric pH towards neutrality, and a twice daily regimen of omeprazole is probably needed. AIM: To assess the effects of twice daily administration of omeprazole 20 and 40 mg. METHODS: Twelve duodenal ulcer patients in remission were randomized to receive in single-blind fashion either placebo, omeprazole 20 mg or omeprazole 40 mg twice daily (08.00 and 20.00 h). On the sixth day of dosing they underwent 24-h gastric pH-metry. RESULTS: Omeprazole 20 and 40 mg b.d. produced marked decreases (P < 0.001) of 24-h gastric acidity (pH 5.4 +/- 0.9 and pH 5.7 +/- 0.6, respectively, vs. a basal pH of 1.4 +/- 0.2) and kept gastric pH at levels higher than 3.0 for almost 24 h. Gastric pH was kept above 5.0 for about 18 h and above 6.0 for about 10 h, while the time spent above 7.0 did not exceed 3 h. There were no significant differences between the two omeprazole dosages at any pH threshold. CONCLUSION: Omeprazole 20 mg b.d. is sufficient to render the gastric milieu as anacidic as possible in duodenal patients.  相似文献   
905.
Normal quantitative circumferential profile limits were established for a 30 degrees bilateral rotating slant-hole (RSH) collimator tomographic system. This system's value in detecting segmental coronary artery disease was assessed in a study evaluating 196 patients by thallium 201 myocardial scintigraphy and coronary arteriography. Profile curves were calculated from images of 20 healthy patients and used to identify significant coronary artery disease (greater than or equal to 70% diameter narrowing) in the left anterior descending (LAD), the right, and the left circumflex (LCx) coronary arteries. In a group of 86 patients, an abnormality on the apical or middle plane optimally identified segmental coronary artery disease. When such abnormalities were prospectively evaluated in a test group of 110 patients, the sensitivity and specificity were 79% and 93% for LAD, 90% and 90% for right, and 83% and 83% for LCx coronary artery disease. Compared with qualitative interpretation of the planar and tomographic images, quantitative tomography significantly improved the sensitivity of T1-201 imaging in detecting LAD, right, and LCx coronary artery disease (P less than .001) in patients with or without previous myocardial infarction.  相似文献   
906.
Zusammenfassung Die qualitative Prüfung des Immunoglobulin-G-Gehaltes durch Agargel-Präzipitation erlaubt die Vermeidung von falschen Ergebnissen bei den Gm-und Inv-Bestimmungen.
Summary The qualitative examination of immune-globulins-G by agar-precipitation prevents erroneous determinations of Gm- and Inv-groups.

Résumé Un examination qualitative des immune-Globulines-G par precipitation en milieu de Gelose (Agar) permets la prévention des résultats faux chez groupages Gm et Inv.
  相似文献   
907.
Photodynamic therapy was performed on ten tumors in patients who did not respond to initial therapy and for whom no additional conventional therapy was available. A sensitizing agent (hematoporphyrin derivative [HpD]) was injected directly into each tumor under computed tomographic (CT) guidance to deliver high concentrations to the tumor and to minimize systemic toxicity. Three to 6 days after the injection, a clear Teflon sheath catheter was placed into the tumor under CT guidance. The tumor was exposed to red light (630-nm wavelength) through laser fiberoptics inserted in the sheath. The initial investigation confirmed the technical feasibility of CT-guided photodynamic therapy by means of intratumoral HpD injections and laser exposure through fiberoptics inserted in sheath catheters. The toxicity from a single treatment was minor, and the tumor response was encouraging.  相似文献   
908.
Zusammenfassung In einer experimentellen Studie wurde an Patienten mit ausgeprägten frontalen Dysgnathiesymptomen und deutlichen Abweichungen von den Kriterien einer optimalen dynamischen Okklusion die Kiefergelenkfunktion untersucht. Mit Hilfe eines Meßplatzes zur simultanen, kontaktlosen Registrierung von Mundöffnungs- und Schließbewegungen und Geräuschen des Kiefergelenkes konnten im Vergleich zu einer eugnathen, gleichaltrigen Kontrollgruppe keine wesentlichen Einschränkungen der Kiefergelenkfunktion festgestellt werden.
Summary In an experimental study we examined the function of the TMJ of patients with a considerable aberration from ideal dynamic occlusion and with obvious symptoms of frontal dysgnathia. Using a measuring seat for the simultaneous recording of opening- and closing movements without occlusal interference and the sounds produced by the TMJ, we could not find any significantly impaired TMJ function compared with an orthognathic control group of similar age.


Nach einem Vortrag, gehalten anläßlich der Jahrestagung der Deutschen Gesellschaft für Kieferorthopädie, Heidelberg 6. bis 10. 6. 1990.  相似文献   
909.
陶亮  王洪新  饶曼人 《药学学报》1995,30(5):326-330
在培养72h的乳鼠心肌细胞,血管紧张素Ⅱ(angiotensinⅡ,AgnⅡ)1,10,100和1000nmol·L-1时,可浓度依赖性地增加细胞搏动频率;而牛磺酸5,10和20mmol·L-1不影响心肌细胞搏动频率,但能浓度依赖性地拮抗AngⅡ100nmol·L-1加快心肌细胞搏动频率的作用。AngⅡ100nmol·L-1连续作用7d引起的培养乳鼠肥大心肌细胞搏动频率加快,动作电位APA升高,APD50和APD90延长,SCL缩短;哇巴因50nmol·L-1诱发的心肌细胞搏动节律失常发生率高于常规培养组。牛磺酸20mmol·L-1可抑制AngⅡ引起的上述改变,并降低哇巴因诱发的心律失常发生率。  相似文献   
910.
A study was undertaken of five patients with Cushing syndrome due to adrenocorticotropin (ACTH) production by thymic carcinoid tumor (primary mediastinal APUDomas), including two recent patients examined by computed tomography (CT) of the chest. Plain roentgenography of the chest initially failed to detect tumor in four of the five patients, while CT of the chest yielded definitive diagnostic information in both patients in whom it was employed. For one of these patients, a mediastinal tumor could be seen retrospectively on plain roentgenograms of the chest, although it had been missed on the first examination. One of the tumors appeared to be partially calcified on CT scan, a finding not previously reported. Blastic osseous metastasis, which is common when malignant carcinoid tumors spread to bone, was seen in one patient. Our data suggest that in patients with suspected ectopic ACTH production, CT scanning of the mediastinum should be performed early in order to avoid delay in diagnosis of an ACTH-secreting carcinoid tumor of the mediastinum.  相似文献   
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