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OBJECTIVE: To determine whether three-dimensional ultrasonography can increase the ability to evaluate the ovary and follicles, especially in women with polycystic ovary disease (PCOD). DESIGN: Prospective clinical study. SETTING: University hospital endocrine and infertility center. PATIENT(S): Sixty-six patients undergoing routine gynecologic evaluation were divided into two groups: the normal control group consisted of 22 patients, and there were 44 patients with PCOD. INTERVENTION(S): Three-dimensional ultrasonography was performed to store and document whole volumes of the ovaries for evaluation. MAIN OUTCOME MEASURE(S): Three perpendicular planes of bilateral ovaries are rotatable to obtain the largest dimensions. The three-dimensional volume was measured using the trapezoid formula. RESULT(S): The ovaries of the patients with PCOD were larger in size, area, and volume than those of normal controls. CONCLUSION(S): Stroma and volume determinations can be obtained more accurately by three-dimensional images than by traditional ultrasonography. Three-dimensional ultrasonography not only facilitates noninvasive evaluation and volume calculation but also completes the examination in a short time without increasing patient discomfort. 相似文献
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ST Manson 《Canadian Metallurgical Quarterly》1992,46(5):2939-2940
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Two human colorectal tumor cell lines are differentially sensitive to growth inhibition by 5-fluorodeoxyuridine (FdUrd); cell line RCA is less sensitive to FdUrd than is cell line C. Thymidylate synthase (TS), a target of FdUrd, has been purified to homogeneity from both cell lines. Because of differences in the avidity for a folate ligand affinity matrix, TS forms from the cells were purified by two different procedures. Relative to the enzyme from C cells, the enzyme from RCA cells demonstrated higher Km values for the substrates deoxyuridylate and 5,10-methylene-tetrahydrofolate, a lower rate of association of the inhibitor 5-fluorodeoxyuridylate (FdUMP), a similar rate of FdUMP dissociation, and lower enhancement of covalent FdUMP binding by folate derivatives. The activities of the enzymes in situ and the catalytic efficiencies of the purified enzymes were similar. Thus, a cell line that is naturally resistant to FdUrd has been identified that expresses a TS with reduced affinity for FdUMP and 5,10-methylenetetrahydrofolate, relative to the enzyme expressed in a FdUrd-sensitive cell line. 相似文献