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1.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
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3.
M A Blankenstein J Szymczak J Daroszewski A Milewicz J H Thijssen 《Gynecological endocrinology》1992,6(1):13-17
Breast cancer tissue is able to maintain the tissue estradiol level in spite of the massive decrease in plasma estradiol associated with menopause, whereas fatty tissue from breasts with malignancies more closely reflects the changes in plasma. In the present study estrone and estradiol levels in fatty tissues from different origins were compared to evaluate the capacity of distant fatty tissues to act as estrogen reservoirs. Abdominal fat was obtained from 25 premenopausal and 20 postmenopausal women who underwent surgery for non-oncological reasons. Estrone and estradiol levels in these tissues were compared to those in breast fatty tissue from breast cancer patients. Plasma estrogen levels were not different in the two groups. In both groups, median plasma estradiol levels dropped sharply with menopause (from 363 to 40 pmol/l in breast cancer patients; from 280 to 45 pmol/l in the non-oncological patients; p less than 0.002), whereas a significant decrease in plasma estrone was observed only in the breast cancer patients (from 238 to 140 pmol/l; p less than 0.02). In premenopausal women, median estrone and estradiol levels in breast fatty tissue (1135 and 375 fmol/g, respectively) and abdominal tissue (1390 and 470 fmol/g, respectively) were not different. In postmenopausal women, however, significantly higher estrone levels (663 vs. 508 fmol/g; p less than 0.01) and estradiol levels (245 vs. 187 fmol/g; p less than 0.02) were found in abdominal fatty tissue. In view of the absolute estrogen levels in breast and abdominal fatty tissue and in plasma, we conclude, however, that it is unlikely that remote fat contributes substantially to the maintenance of estrogen levels in breast cancer tissue. 相似文献
4.
Focal liver lesions: characterization with triphasic spiral CT 总被引:15,自引:1,他引:14
5.
Endoscopic Sphincterotomy and Biliary Drainage in Patients with Cholangitis Due to Common Bile Duct Stones 总被引:13,自引:0,他引:13
6.
Metabolic adaptation of the chick embryo to chronic hypoxia 总被引:1,自引:0,他引:1
7.
Von H.-E. Künzel G. D. Wolf F. Bentz G. Blankenstein G. E. Nischk 《Macromolecular chemistry and physics.》1969,130(1):103-144
In the production of high molecular weight aromatic polyamides which are soluble in polar solvents, novel aromatic diamines with oxdiazole, triazole, thiadiazole, thiazole, hydantoin, quinazolone and quinazolinedione ring systems – some of the novel aromatic diamines contain ether or sulfone groups – are reacted with aromatic dicarboxylic acid dichlorides (e.g. iso- or terephthaloyl dichloride) in polar organic solvents (e.g. N.N-dimethylacetamide or N-methyl-pyrrolidone). Filaments and fibres which possess a very good strength and a high thermal stability can be produced. Polyamides of diamines with quinazolinedione ring systems are most stable to high temperatures and are further distinguished by being only slightly liable to combustion. The new polyamides dissolved in polar solvents are suitable in the production of flexible films which are stable to high temperatures. 相似文献
8.
Marion Dorsch Hanno Hock Ulrich Kunzendorf Tibor Diamantstein Thomas Blankenstein 《European journal of immunology》1993,23(1):186-190
In order to analyze the effect of a high local concentration of macrophage colony-stimulating factor (M-CSF; CSF-1) on tumor growth, the plasmacytoma cell line J558L was transfected with the human M-CSF gene and injected into syngeneic BALB/c mice. In contrast to the parental tumors, M-CSF transfectants were heavily infiltrated by macrophages as evidenced by immunohistochemistry with antibodies to Mac-1 and Mac-3 and by isolation of the macrophages from the tumor. Nevertheless, tumor growth was only slightly affected by M-CSF and M-CSF-producing cells grew as tumor in all cases. The growth retardation of M-CSF-producing cells varied depending on the experiment and seemed to be due to an indirect effect because the growth rate of the cells in vitro had not changed upon gene transfer. Attempts to activate the tumor-infiltrating macrophages for tumor suppression by systemic application of interferon-γ and/or lipopolysaccharide were not successful. Altogether, our results suggest that M-CSF is a potent chemoattractant for macrophages in vivo but alone is not sufficient to activate these macrophages for tumoricidal activity. 相似文献
9.
M. A. Blankenstein J. J. Broerse M. J. van Zwieten H. J. van der Molen 《Breast cancer research and treatment》1984,4(2):137-141
Summary Prolactin is associated with the development of mammary tumors in rats. The aim of the present study was to evaluate whether strain differences in susceptibility to the development of mammary tumors could be explained by genetic differences in the response of the pituitary to chronic stimulation by estrogens. Prolactin levels were measured in plasma from rats of the Sprague-Dawley, Wistar WAG/Rij and Brown Norway BN/BiRij strains before and at different times after subcutaneous implantation of estradiol-17 in cholesterol/paraffin pellets. In all strains plasma prolactin was elevated from the second week after implantation of the pellet, although there were quantitative differences between the responses. At 32 weeks after implantation of the pellets the plasma level of prolactin in Sprague-Dawley rats was 1247 ± 367 ng NIAMDD prolactin RP-1/ml (mean ± S.E.M), whereas Wistar WAG/Rij and Brown Norway BN/BiRij had plasma prolactin levels of 679 ± 211 and 182 ± 19 ng/ml respectively. Between 52 and 104 weeks after implantation these values rose to 4016 ± 1116, 5004 ± 1053 and 808 ± 129 ng/ml respectively. The plasma concentration of prolactin of rats in this age group was strongly associated with the occurrence of pituitary adenomas in all three strains. In untreated rats, the concentration of prolactin in the plasma increased with age to only 200–400 ng/ml at 12–24 months of age but no significant differences were observed between the three rat strains. It is concluded that observed differences in spontaneous and estrogen-mediated mammary tumor development in these rat strains cannot be explained by genetic differences in the plasma concentration of prolactin. The development of malignant mammary tumors after estrogen treatment appears to be associated with the extent of the increase in plasma prolactin induced by the estrogen. 相似文献
10.
Rodd HD Blankenstein R 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》1995,5(1):9-14
The aim of the study was to determine the prevalence of iron-deficiency anaemia in children less than 6 years of age who attended for outpatient general anaesthesia for dental extractions. Pre- or peri-operative capillary blood samples were taken from 109 children (70 white Caucasian and 39 ethnic-minority children). The haemoglobin concentration (Hb), mean cell volume (MCV) and red cell porphyrin (RCP) value were determined for each subject. 19% of the children were found to be anaemic (Hb < 11 g/dl) and there was no statistically significant difference for mean Hb or prevalence of anaemia between white Caucasian and ethnic-minority children. A significantly greater proportion of the ethnic-minority children were iron deficient, as indicated by low MCV and high RCP. There were no statistically significant differences between anaemic and non-anaemic subjects with regard to sex or social class, but a significantly greater mean number of extractions were performed in the anaemic children. 相似文献