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161.
TS Howe 《Canadian Metallurgical Quarterly》1998,27(2):188-191
Breast cancer patients receiving tamoxifen (Tam) are at an increased risk for developing endometrial carcinomas, possibly due to the partial estrogenic effect of Tam on endometrial cells. Progestational therapy has not routinely been included in Tam regimens. It was our aim to determine the presence of estrogen receptors (ERs) and progesterone receptors (PRs) in normal and abnormal endometria from postmenopausal women with breast cancer who were treated with Tam. Standard immunohistochemical staining of ERs and PRs was performed on paraffin sections from formalin-fixed uterine curettings or hysterectomy specimens from 40 patients who had received 20-40 mg of Tam daily for a minimum of 3 months. For comparison, normal endometria from 20 women who had not received Tam (11 premenopausal, 9 postmenopausal) were also studied for ER and PR expression. Staining was evaluated using semiquantitative immunoreactivity scores (IRS) ranging from 0 (negative) to 12 (strongly positive). In the group of patients receiving Tam, ERs and PRs were detected in the nuclei of glandular cells in 24/24 cases of endometrial atrophy (ER/PR-IRS, 2-12), in 8/8 endometrial polyps (ER-IRS, 6-12; PR-IRS, 4-12), in 4/4 adenomatous endometrial hyperplasias (ER-IRS, 3-8; PR-IRS, 1-12), and in 4/4 well-differentiated endometrioid adenocarcinomas (ER-IRS, 2-12; PR-IRS, 6-8). Of the 11 endometria from premenopausal patients who had not received Tam, 8 were ER+/PR+ (ER-IRS, 1-12; PR-IRS, 1-12), 1 was ER+/PR- (ER-IRS, 3; PR-IRS, 0), 1 was ER-/PR+ (ER-IRS, 0; PR-IRS, 2), and 1 was ER-/PR- (ER/PR-IRS, 0). Among 9 atrophic endometria from women not treated with Tam, 6 were ER+/PR+ (ER-IRS, 4-12; PR-IRS, 3-6), 1 was ER+/PR- (ER-IRS, 4; PR-IRS, 0), and 2 were ER-/PR- (ER/PR-IRS, 0). The consistent finding of ER and PR expression in endometria from postmenopausal women receiving Tam further supports the suspected estrogenic effect exerted by Tam on endometrial cells. Progestational therapy could be beneficial in the prevention of Tam-induced abnormal endometrial proliferations. 相似文献
162.
AIMS: Progressive loss of neuroretinal rim tissue is known to occur early in glaucoma and measurement of the neuroretinal rim area is possible by magnification corrected analysis of optic disc photographs (planimetry). This study was performed to determine whether the facility to distinguish between glaucomatous and normal optic discs could be improved upon by: (a) taking into account the known relation between optic disc size and neuroretinal rim area, and (b) measuring rim area in a number of segments, in order to detect focal changes. METHODS: Planimetric examination of the optic disc photographs of 88 control subjects and 51 patients with early visual field defects was performed. In the control group, multiple linear regression analysis was performed between neuroretinal rim area and optic disc area, age, sex, eye side, refraction, and keratometry. This was repeated for the whole disc and for each of twelve 30 degree segments. Normal ranges were defined by the 98% prediction intervals of the regression analysis and the sensitivity and specificity for correct identification of optic discs in the two groups determined. RESULTS: Multiple linear regression demonstrated significant associations between the neuroretinal rim area and optic disc area and age in normal subjects. Sensitivity and specificity for glaucoma diagnosis, using the cut off derived from the 98% prediction intervals, was 37.7% and 98.9% respectively when total neuroretinal rim area alone was considered, and 88.7% and 94.3% respectively when the 30 degree segments were included. The most frequent pattern of neuroretinal rim loss was diffuse, followed by thinning in more than one sector and then by thinning in the inferotemporal sector alone. CONCLUSIONS: This method of optic disc analysis enables the examiner to identify glaucomatous optic discs at the stage of early perimetric loss with a high degree of precision. Optic disc photography is simple, and fundus cameras are widely available. This method for glaucoma case identification may therefore be suitable for the primary care setting as well as hospital practice. 相似文献
163.
DH Turnbull JA Ramsay GS Shivji TS Bloomfield L From DN Sauder FS Foster 《Canadian Metallurgical Quarterly》1996,22(7):845-853
The incidence and mortality rate of cutaneous melanoma continue to increase throughout the world, making the study of melanoma biology an important area of current research. While recent breakthroughs in transgenic mouse technology have led to promising mouse skin models of melanoma, there is presently no technique available for quantitatively studying subsurface melanoma progression, in vivo. We demonstrate the first application of an imaging method called ultrasound backscatter microscopy (UBM) for imaging early murine melanomas with spatial resolution of 30 microns axial and 60 microns lateral. Murine B16 F10 melanomas have been imaged from their earliest detection, over several days, until they are 2 to 5 mm in diameter. Melanoma dimensions measured by UBM were found to be in excellent agreement with those determined histopathologically on the excised tumours. The relative rms errors in UBM-determined melanoma height and width were found to be 8.7% and 4.2%, respectively. The mean rate of increase in tumour height of early murine melanoma was found to be 0.37 +/- 0.06 mm/day. Computer-generated volumetric renderings of melanomas have been produced from three-dimensional image data, allowing quantitative comparisons of tumour volumes to be made. Using a priori assumptions of ellipsoid tumour shape, the relative error in UBM-determined volume was shown to be less than 17%. These results should be of considerable interest to investigators studying melanoma biology using mouse skin models, and have implications in the use of high frequency ultrasound imaging for the clinical assessment of cutaneous melanoma. 相似文献
164.
TS Ravikumar 《Canadian Metallurgical Quarterly》1996,5(2):271-282
The histaminergic system is involved in the control of arousal in the brain and may impact significantly on visual processing. However, little is known about the histaminergic innervation of visual areas, or the histamine system in the primate brain, in general. We examined in Macaca mulatta the location of histamine-immunoreactive neurons and the innervation of important cortical and subcortical visual areas by histamine-immunoreactive axons. Brain sections were treated with an antibody to histamine and processed with standard immunohistological procedures. Histamine-immunoreactive neurons (20-45 microns in diameter) were localized bilaterally in the hypothalamus, particularly in ventral, lateral, posterior, and perimammillary hypothalamic areas. These hypothalamic cells appear to provide the sole neural source of histamine in the macaque brain. A plexus of varicose histamine-immunoreactive axons was present throughout the superior colliculus, the dorsal and ventral lateral geniculate nuclei of the thalamus, the reticular nucleus of the thalamus, the lateral posterior/pulvinar complex, and the visual cortex, including areas 17, 18, and the nearby extrastriate cortex. The axons nearly homogeneously innervated every region and layer in these structures, except for an increase in density in layer 1 of the visual cortex and in the superficial-most layers of the superior colliculus. Histaminergic axons broadly innervated every visual region examined. In comparison with the other aminergic and the cholinergic projection systems, which show considerable projection specificity, the histaminergic projection exhibited great homogeneity. The breadth of the distribution of histaminergic axons ensures that virtually all levels of visual processing in the primate can be influenced, either directly or indirectly, by the neuromodulatory effects of histamine. 相似文献
165.
Since there is a much longer uterine nuclear retention of the U-11, 100A (antiestrogen) receptor complex (UARC) than of the estradiol receptor complex (ERC) at 4-12 hrs after injection, experiments were designed to determine if there is a difference between the relative nuclear affinities for the two RCs as determined by extraction with various ionic strength mediums. Although the UARC was retained longer in the nuclear fraction in vivo, the UARC was completely extractable with 0.3M KCl or 50mM spermine, whereas the ERC demonstrates a salt-resistant form. This suggests that the ERC is more tightly bound to nuclear components through this salt-resistant form of the receptor. In addition, various intercalating agents were used to distinguish the different nuclear chromatin DNA sites where the UARC and ERC may be binding. With actinomycin D (50 uM) more ERC than UARC was retained in the nuclear fraction. However, with ethidium bromide (100uM) less ERC than UARC was retained. Also, the ERC selectively released by ethidium bromide is precisely that fraction not released by salt. These results indicate that the UARC and ERC bind to different chromatin loci. 相似文献
166.
167.
We have taken a stepwise approach to improving the dosing of continuous intravenous heparin in patients with acute coronary syndromes. Our primary objective was to use computer modeling to develop a nomogram for managing heparin therapy and to put in place a continuous quality monitoring system to evaluate the nomogram's effectiveness. We prospectively collected data on 41 patients with unstable angina or myocardial infarction who were treated with heparin. Their response to heparin was computer modeled and the dose to achieve an activated partial thromboplastin time (aPTT) ratio of 2.0 was established. This dose was regressed against all demographic characteristics to establish predictors of heparin dose (phase I). The regression formula was used prospectively in 110 patients to initiate the infusion rate of heparin and a bolus dose to achieve an aPTT ratio of 2.5. Subsequent dosage adjustments were achieved by computer modeling the patient's aPTT response (phase II). A nomogram was developed that simulated the decisions achieved using computer-assisted methods. This was retrospectively tested and then prospectively tested in 50 patients using nursing staff (phase IV). The nomogram was then made generally available (phase IV) and has been tested in an additional 310 patients. Phase I: Of the original 41 patients, 32% of the aPTT ratios were in the therapeutic range, 36% were supratherapeutic, and 32% were subtherapeutic after the first 24 hours. Phases II and III resulted in 85% of the aPTT ratios between 1.5 and 2.5 at 24 hours. Phase 4 had similar results in 310 patients. The use of computer-assisted or a computer-generated nomogram to adjust heparin therapy results in better control of heparin therapy than using standard methods. 相似文献
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