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511.
To determine the role of the insulin receptor overexpression in breast epithelial cell transformation, the 184B5 human breast epithelial cell line was transfected with human insulin receptor cDNA. In two cell lines transfected with and overexpressing human insulin receptors (IR) (223.8 and 184.5 ng IR/10(6) cells), but not in untransfected cells, insulin binding and tyrosine kinase activity were elevated, and insulin induced a dose-dependent increase in colony formation in soft agar. 相似文献
512.
The conducted studies indicated the diagnostic opportunities of a cytologic analysis of exudates and smears from the Douglas space in patients with a suspicion to ovarian tumor. Tumor cells may be present in the peritoneal cavity not only in different stages of malignant ovarian tumors, but also in secernent and proliferating cystadenomas. A correlation between the peritoneal cell content in patients with different forms of ovarian neoplasms and press-smears from the dissected surface of the removed tumors and histological sections indicated the morphological identitiy of tumor elements and enabled the determination of the cytological criteria for the differential diagnosis of ovarian tumors prior to surgical intervention. 相似文献
513.
SN Skopinskaia ID Riabova IV Galushchenko EP Severina VL Boroviagin 《Canadian Metallurgical Quarterly》1976,41(10):1791-1797
A comparative study of ultrastructure and IR-spectroscopy of osmotic shock membranes from cells of glycolyzing (Streptococcus faecalis) and respiring (Micrococcus lysodeikticus) bacteria, was made. The S. faecalis and M. lysodeikticus membranes differ in their cross-section. Treatment of the preliminary washed membranes of S. faecalis and M. lysodeikticus with a low ionic strength solution removes 40% and 70% of their proteins respectively, decreases the membrane cross-section but does not change their fracture faces. Pre-cooling of the membrane suspensions within the temperature range of +5 degrees-10 degrees results in the appearance of large smooth areas on S. faecalis membrane fracture faces, but does not affect the ones of M. lysodeikticus membrane. Treatment of the washed suspensions with Triton X-100 results in the appearance of drastic changes of S. faecalis membrane fracture faces and does not change the fracture faces of M. lysodeikticus membranes; treatment by the detergent does not alter the IR-spectroscopy of membranes of both bacteria. Treatment of S. faecalis and M. lysodeikticus membranes with high temperature irreversibly changes the structure of 20% and 40% of protein components respectively,, but does not affect the distribution of the subparticles on their fracture faces. It is assumed that the differences found are determined by the composition of lipid components of the membranes studied and that the amount of proteins closely bound with lipids in the membranes of S. faecalis is likely to be greater than that of M. lysodeikticus membranes. 相似文献
514.
J O'Connor D Ballantyne JG Pollock B Cairney TD Lawrie 《Canadian Metallurgical Quarterly》1977,27(3):325-331
Fourteen patients with hyperlipoproteinaemia and peripheral vascular disease have been investigated to determine the effect on limb blood flow of hypolipidaemic therapy. Satisfactory lowering of serum lipoprotein levels was achieved in the treated group. There was a significant deterioration in peak reactive blood flow measurements in the placebo group compared with the treated group. Treatment of hyperlipoproteinaemia may, therefore, be of value in preventing the progression of peripheral atherosclerosis. 相似文献
515.
516.
Paula Aldaz Natalia Martín-Martín Ander Saenz-Antoanzas Estefania Carrasco-Garcia María lvarez-Satta Alejandro Elúa-Pinin Steven M. Pollard Charles H. Lawrie Manuel Moreno-Valladares Nicols Samprn Jürgen Hench Robin Lovell-Badge Arkaitz Carracedo Ander Matheu 《International journal of molecular sciences》2022,23(9)
517.
Padin S Staniszewski Z Keisler R Joy M Stark AA Ade PA Aird KA Benson BA Bleem LE Carlstrom JE Chang CL Crawford TM Crites AT Dobbs MA Halverson NW Heimsath S Hills RE Holzapfel WL Lawrie C Lee AT Leitch EM Leong J Lu W Lueker M McMahon JJ Meyer SS Mohr JJ Montroy TE Plagge T Pryke C Ruhl JE Schaffer KK Shirokoff E Spieler HG Vieira JD 《Applied optics》2008,47(24):4418-4428
The South Pole Telescope is a 10 m diameter, wide-field, offset Gregorian telescope with a 966-pixel, millimeter-wave, bolometer array receiver. The telescope has an unusual optical system with a cold stop around the secondary. The design emphasizes low scattering and low background loading. All the optical components except the primary are cold, and the entire beam from prime focus to the detectors is surrounded by cold absorber. 相似文献
518.
BACKGROUND: The National Cancer Data Base (NCDB) represents a national electronic registry system now capturing nearly 60% of incident cancers in the U. S. In combination with other Commission on Cancer programs, the NCDB offers a working example of voluntary, accurate, cost-effective "outcomes management" on a both a local and national scale. In addition, it is of particular value in capturing clinical information concerning rare cancers, such as those of the thyroid. METHODS: For the accession years 1985-1995, NCDB captured demographic, patterns-of-care, stage, treatment, and outcome information for a convenience sample of 53,856 thyroid carcinoma cases (1% of total NCDB cases). This article focuses on overall 10-year relative survival and American Joint Committee on Cancer (AJCC) (3rd/4th edition) stage-stratified 5-year relative survival for each histologic type of thyroid carcinoma. Care patterns also are discussed. RESULTS: The 10-year overall relative survival rates for U. S. patients with papillary, follicular, Hürthle cell, medullary, and undifferentiated/anaplastic carcinoma was 93%, 85%, 76%, 75%, and 14%, respectively. For papillary and follicular neoplasms, current AJCC staging failed to discriminate between patients with Stage I and II disease at 5 years. Total thyroidectomy +/- lymph node sampling/dissection represented the dominant method of surgical treatment rendered to patients with papillary and follicular neoplasms. Approximately 38% of such patients receive adjuvant iodine-131 ablation/therapy. At 5 years, variation in surgical treatment (i.e., lobectomy vs. more extensive surgery) failed to translate into compelling differences in survival for any subgroup with papillary or follicular carcinoma, but longer follow-up is required to evaluate this. NCDB data appeared to validate the AMES prognostic system, as applied to papillary cases. Younger age appeared to influence prognosis favorably for all thyroid neoplasms, including medullary and undifferentiated/anaplastic carcinoma. NCDB data also revealed that unusual patients diagnosed with undifferentiated/anaplastic carcinoma before age of 45 years have better survival. CONCLUSIONS: The NCDB system permits analysis of care patterns and survival for large numbers of contemporaneous U. S. patients with relatively rare neoplasms, such as thyroid carcinoma. In this context, it represents an unsurpassed clinical tool for analyzing care, evaluating prognostic models, generating new hypotheses, and overcoming the volume-related drawbacks inherent in the study of such neoplasms. [See editorial on pages 2434-6, this issue.] 相似文献
519.
Three new naphthalenes, designated as syriacusins A-C, were isolated from the root bark of Hibiscus syriacus. These compounds were identified as 2,7-dihydroxy-6-methyl-8-methoxy-1-naphthalenecarbaldehyde, 2-hydroxy-6-hydroxymethyl-7,8-dimethoxy-1-naphthalenecarbaldehyde, 1-carboxy-2,8-dihydroxy-6-methyl-7-methoxynaphthalenecarbolactone (1-->8), respectively, on the basis of various spectral studies. The compounds inhibited lipid peroxidation with IC50s of 0.54, 5.90 and 1.02 micrograms ml-1, respectively. The first compound also showed cytotoxicity against some human cancer cell lines with an ED50 of 1.5-2.4 micrograms ml-1. 相似文献
520.
更易于从新的地理数据中提取信息的专家分类系统 总被引:3,自引:0,他引:3
1 引言十年能产生什么差别 ?正如 1 0年前 ,羽毛渐丰的地理技术 ( geotechnology)工业正蹒跚地寻找新的地理数据源以满足地理信息系统增长的需要 ,同样地 ,我们遥感界也花费了 2 0世纪 90年代的大部分时间去设计先进的影像卫星 ,优化数字化技术和创建新的数字数据集。作为以上努力的结果 ,遥感界现在所面临的是几乎对立的挑战。空间数据用户能够登录到互联网上去获取令人惊愕的各种卫星影像、数字高程模型( DEM)、预打包 ( pre- packaged)的矢量文件以及其它地理数据 ,这些数据都是以数字格式的而不是模拟的。随着空间数据种类的增加 ,这… 相似文献