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121.
Problem areas within a proficiency testing (PT) program are performance evaluation and sample stability. The different units used in the various T3 uptake methodologies make performance evaluation complex. To facilitate this evaluation, a normalization method for T3 uptake performance evaluation has been developed. Sample stability studies for T3 uptake indicate that, at room temperature, sample values increase after storage for about seven days. Room temperature sample stability studies for T4 using a competitive protein binding (CPB) method indicate that the apparent T4 content of pooled serum increases after about one week. Fatty acids are shown to be an interfering substance in the T4 CPB method as well as the T4 radioimmunoassay (RIA) method. This interference increases with a decrease in carbon chain length from C18 to C12 and with an increase in unsaturation of fatty acids. The B/B0 ration for arachidonic acid at a concentration of 0.48 micronMoles per tube is 17.4 in a CPB method and 87.1 in a radioimmunoassay method indicating that the greater effect is in the CPB method. The increase in T3 uptake values are probably also due to the interfering effect of fatty acids. 相似文献
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Iodine-131, ruthenium-103, and neptunium-239 are present as contaminants in the eluate of 99Mo-99mTc generators loaded with 99Mo prepared by thermal-neutron irradiation of enriched 98Mo. The elution pattern of each of these contaminants is determined, together with the amounts found in the eluate of all generators tested over a 7-month period. 相似文献
124.
Ulnar nerve entrapment at the elbow has been described in the literature. This paper deals with 19 skeletally mature baseball players with ulnar nerve entrapment who underwent surgery for correction of the problem. The surgery consisted of anterior transfer of the nerve and placement deep to the flexor muscles. Six players quit baseball because of continuing elbow problems, nine returned to playing, and four were lost to follow-up. Ulnar nerve entrapment is thought to represent one syndrome in a spectrum of diseases involving the medial side of the elbow in baseball players. The lesion is amenable to surgery. 相似文献
125.
W. J. Rietveld 《Journal of chemical ecology》1983,9(2):295-308
Laboratory experiments were conducted to determine juglone sensitivity of 16 species (Trifolium incarnatum, Coronilla varia, Vicia villosa, Lespedeza stipulacea, L. cuneata, Acer ginnala, Caragana arbor-escens, Elaegnus angustifolia, E. umbellata, Lonicera maackii, Quercus alba, Fraxinus americana, Liriodendron tulipifera, Alnus glutinosa, Pinus strobus, andP. sylvestris) being considered for mixed plantings withJugions nigra (black walnut). All species were sensitive to juglone, but seed germination and radicle elongation were less affected than shoot elongation and dry weight accumulation. Seed germination and radicle elongation were affected by juglone in 6 and 11 species, respectively, mainly by the higher concentrations (10?3 M and 10?4 M). Shoot elongation and dry weight accumulation of all species were affected by juglone; many species were sensitive to concentrations as low as 10?6 M. Seedlings of all species were severely wilted and eventually killed by 10?3 M juglone, and most were chlorotic and severely retarded by 10?4 M juglone. Seedlings inhibited by 10?6 M and 10?5 M juglone did not showany visible signs of injury. Based on the effects on seedling shoot elongation and dry weight accumulation, the five species found to be most sensitive to juglone were:Lonicera maackii, Lespedeza cuneata, Trifolium incarnatum, Alnus glutinosa, and Elaeagnus umbellata. 相似文献
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The results of a prospective study of laparoscopic management of ovarian cysts are discussed. This technique of minimally invasive surgery was introduced at the department of Gynaecology of the Leiden University Medical Centre in 1991. Only premenopausal women with unilocular ovarian cysts smaller than 10 cm in diameter and with sonographically benign characteristics were included in this study. In a period of one year, 25 cystectomies and one ovariectomy were performed. 88% of the cysts were initially treated with hormone therapy. Mean age of the patients was 30 years (range: 21-54), average size of the cysts was 6 cm (range: 4-10) and mean operating time was 80 minutes (range: 35-120), there were no complications during operation or in the postoperative period. No laparotomies had to be performed. Three times (11.5%) pathological specimen examination revealed a corpus luteum cyst. The other 23 were non-functional cysts. No carcinoma was detected. The results of this minimally invasive surgery for removal of ovarian cysts are encouraging. Morbidity compared with the conventional cystectomy by laparotomy is low as appears from a shorter hospital stay and quicker recovery. Cystectomy of the ovary, compared with laparoscopic aspiration and fenestration, has a better therapeutic effect and the histological evaluation is more reliable. Persistent, unilocular ovarian cysts, which fulfill the criteria used in our study, are best treated by laparoscopic removal instead of laparotomy. 相似文献
130.
B Schwilk L Friess W Friesdorf FW Ahnefeld M Georgieff 《Canadian Metallurgical Quarterly》1993,28(8):484-492
OBJECTIVE: The relation of the frequency and severity of pitfalls, events and complications (PECs) was analysed in respect of preoperative risk factors. The epidemiological data were gathered as a contribution to a current project of the German Society for Anaesthesiology and Intensive Care. METHOD: Preoperative data (age, sex, preexisting diseases, pathological findings, grade of urgency and ASA-class) were integrated in a paper record, as well as the perioperative interventions and directly postoperative events, type of anaesthesia, and kind of operation. The automatically readable paper records were routinely in use for every patient. After control and correction the data were stored in a modern data base. MAIN RESULTS: From October 1, 91 to May 20, 92 11,890 anaesthesias were recorded. 2,959 of them with a total of 4,184 PECs. 2,397 PECs were cardiovascular, 875 respiratory. PECs of grade I (no impact on treatment in the recovery room [RR]) occurred in 14% of patients, grade II (impact on treatment in RR, but no impact on discharge to ward) 7.2%, grade III (prolonged stay in RR or special monitoring in the ward) 2.88%; grade IV (PEC leads to transfer to the ICU) 0.63%, and grade V (PEC leads to disabling damage or death) 0.13%. 13 of 15 patients suffering from PECs grade V were of ASA class 4 or 5. PECs had a certain relation to the ASA-classification of anaesthetic risk. But this relation is quite different in several surgical disciplines. CONCLUSIONS: Preoperatively known risk factors of the patient and the measures taken by specialists of various disciplines contribute to the incidence of PECs. Available data could be processed multicentrally and in standard form for producing prognostic data for risk prediction. Since PECs of grade II or higher are cost- relevant, requiring an interdisciplinary approach, it appears meaningful to base costing on such an interdisciplinary approach in accordance with the requirements of diagnosis and treatment. 相似文献