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881.
Specific antiserum for 17-hydroxyprogesterone (17-OH-P) was prepared by immunizing 7 alpha-(2-carboxyethylthio)-17-OH-P conjugated bovine serum albumin (BSA) in rabbits. Using this antiserum, 17-OH-P enzyme immunoassay for dried blood spots on filter paper was established. As a label, alkaline phosphatase was coupled covalently with 7 alpha-carboxy-methylthio-17-OH-P by carbodiimide method. B/F separation was carried out by the addition of anti-rabbit IgG goat antiserum. All specimens used were punched out with a paper puncher of 3mm diameter. The assay sensitivity was 2pg/tube, which was estimated by two standard deviation at zero concentrations of the calibration curve. Cross reactivities of this antibody were as follows: 11-deoxycortisol (8.21%), 17-OH-pregnenolone (3.33%), progesterone (1.67%), 11-deoxycorticosterone (0.31%), cortisol (0.16%), pregnenolone-3-sulfate Na salt (0.03%), dehydroepiandrosterone (DHEA) (less than 0.03%), 16 alpha-OH-DHEA (less than 0.03%), DHEA-3-glucuronide (less than 0.03%), DHEA-3-sulfate Na salt (less than 0.03%), pregnenolone (less than 0.02%). Intra- and inter-assay coefficient of variations were 4-14% and 9-18%, respectively. In normal babies, 17-OH-P concentrations measured directly (without sample extraction) were below 23pg/disk (n=204). The histogram of 17-OH-P level in normal babies obtained by the direct method was distributed lower than that obtained by the enzyme immunoassay system (range: 4-79pg/disk, n=268) which used antibody raised against 17-OH-P-3-O-carboxymethyloxime conjugated BSA (Enzaplate, Sapporo Diagnostic Laboratory).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Despite >50 years of research work since the discovery of sliding filament mechanism in muscle contraction, structural details of the coupling of cyclic cross-bridge movement to ATP hydrolysis are not yet fully understood. An example would be whether lever arm tilting on the myosin filament backbone will occur in the absence of actin. The most direct way to elucidate such movement is to record ATP-induced cross-bridge movement in hydrated thick filaments. Using the hydration chamber, with which biological specimens can be kept in an aqueous environment in an electron microscope, we have succeeded in recording ATP-induced cross-bridge movement in hydrated thick filaments consisting of rabbit skeletal muscle myosin, with gold position markers attached to the cross-bridges. The position of individual cross-bridges did not change appreciably with time in the absence of ATP, indicating stability of time-averaged cross-bridge mean position. On application of ATP, individual cross-bridges moved nearly parallel to the filament long axis. The amplitude of the ATP-induced cross-bridge movement showed a peak at 5–7.5 nm. At both sides of the filament bare region, across which the cross-bridge polarity was reversed, the cross-bridges were found to move away from, but not toward, the bare region. Application of ADP produced no appreciable cross-bridge movement. Because ATP reacts rapidly with the cross-bridges (M) to form complex (M·ADP·Pi) with an average lifetime >10 s, the observed cross-bridge movement is associated with reaction, M + ATP → M·ADP·Pi. The cross-bridges were observed to return to their initial position after exhaustion of ATP. These results constitute direct demonstration of the cross-bridge recovery stroke.  相似文献   
885.
Pathology of the thyroid gland tissue was characterized in patients with Triiodothyronine (T3)-predominant Graves' disease who had normal levels of serum T4 but increased levels of serum T3 during antithyroid drug therapy. In order to compare this group of patients with an usual type of Graves' patients, age, sex, dietary intake of iodide, duration of antithyroid therapy and the dose of thionamide drugs were matched between the two groups of patients. Thyroid tissue was obtained from subtotal thyroidectomy. In examining the histology of the thyroid gland, integration eye piece plate II with regularly arranged 100 lattice points was set on eye lens of a microscope. The number of crossing points which were projected on each 4 histological elements was counted in randomly selected 10 fields of vision in each patient's thyroid. Assuming that the every histological element is arranged in a random manner, errors of each visual field by this method would be less than 12%. In consequence, the significant difference was demonstrated in the weight of subtotally resected thyroid and the ratio of each histological element except interstitial tissue occupied in the total thyroid tissue between T3-predominant Graves' disease and control Graves' disease. The volume composition of the epithelial cells and vacuoles in patients with T3-predominant Graves' disease was significantly greater than that of patients with control Graves' disease (24.7 +/- 10.6 vs 14.4 +/- 6.5%, 5.9 +/- 3.9 vs 2.0 +/- 1.0%, Mean +/- SD, respectively, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
886.
A 69-year-old Japanese female was admitted to our hospital due to a 2-month history of vomiting after eating. Examination of the small intestinal tract revealed a tumor with calcification in the inner portion, from the horizontal portion to the ascending portion of the duodenum, and jejunojejunostomy was performed. The pathological findings of the tumor gave a diagnosis of non-Hodgkin's lymphoma, diffuse small cleaved cell (Working Formulation classification), B cell type, of the jejunum. Calcification is rarely found in untreated malignant lymphoma and 15 cases of untreated malignant lymphoma with calcification have been reviewed.  相似文献   
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Background: The aim of the present study was to establish L3 fraction before initial treatment as a useful prognostic factor in a prospective fashion in hepatocellular carcinoma (HCC) where the alpha-fetoprotein (AFP) was very low. Methods: From 1990 to 2004, 298 HCC patients in whom L3 could be measured were examined in the present study. Enrolled patients with HCC underwent operation, transcatheter arterial chemoembolization and percutaneous ablation therapy. The current patient status was confirmed as of the end of March 2005. L3 was determined by crossed immuno-affinoelectrophoresis when AFP was >/=30 ng/mL. It was carried out by liquid-phase binding assay system on cases where AFP < 30 ng/mL. The tentative discriminating line of L3 was set at 15%. Results: The HCC group included four subgroups: 110 patients with AFP concentrations 15% (high L3), was significantly lower than that in the HCC group whose L3 was 相似文献   
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