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The aim of this study was to analyze the characteristics of 17 women with renal-cell carcinoma (RCC) associated with other primary neoplasms occurring in steroid-hormone target tissues. The reproductive history of these patients and the use of exogenous hormones were taken into consideration. In all, 10 RCCs were associated with breast carcinoma; 4, with endometrial carcinoma; and 3, with ovarian carcinoma. The presentation of a second primary tumor was described as synchronous or metachronous by evaluation of the interval between the discovery of the two neoplasms. Hormone and surgical treatment as well as pathologic findings for each primary tumor were also reported. In these 17 RCCs the overall rate of disease-specific survival recorded after a mean follow-up period of 32.7 months (range 9–66 months) was 58.8%; 7 patients died of metastatic disease after surviving for a mean of 14.7 months. In terms of the pathologic stage of RCC, a significant difference in mean survival was found between pN0 (mean survival 22.1 ± 3.4 months) and pN 1 RCCs (mean survival 13.7 ± 3.5 months). A total of 13 (76.4%) women were postmenopausal at the time of diagnosis of the first primary tumor; the mean age of these women at menopause was 51.7 ± 1.2 years. No prior use of oral contraceptives was reported by 12 (70.5%) of the 17 patients. Plasma 17-beta-estradiol and estrone levels were determined in only 7 patients at the diagnosis of each of the primary tumors. High plasma estrogen levels were found in 4 women with RCC and breast carcinoma and in 1 patient with RCC and endometrial carcinoma; in the remaining 2 patients low-normal values were found. A relationship appears to exist between certain reproductive and hormone-related factors and the risk of developing these tumor associations. Data emerging from the present study do not provide strong support for the hypothesis of hormone dependency of RCC; however, a role for estrogens in cases in which RCC is associated with other primary tumors involving steroid-hormone target tissues can be hypothesized.  相似文献   
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Summary Five Rhesus Monkeys (Maccaca mulatta), a suitable nonhuman model, performed 5 months of ropeclimbing exercise. Duration of the training sessions was progressively increased to reach 1 hour/day after 1 month of training and was maintained until the end of the experiment. Bone mass parameters, bone resorption, and bone formation activity were measured by histomorphometric analysis on iliac crest bone biopsies before and after the experiment. Mineral apposition rate was measured in cortices and trabecular bone after double calcein labeling. Five months of rope-climbing exercise had determined a significant decrease of bone volume with a slight decrease of the number and thickness of trabeculae. This might induce an alteration of biomechanical properties of bone. These architectural modifications were associated with a nonsignificant decrease of bone resorption activity. But the main effect of training was an important decrease of bone formation activity without change of the mineral apposition rate. Endurance exercise at low intensity has determined a decreased bone turnover with osteoblastic depression. This animal experiment points out that exercise modalities might be important in the bone response to training and should be carefully defined for preventive use in humans.  相似文献   
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Assessment of fluctuations in heart rate (HR) following a premature ventricular complex (PVC) is valuable for identifying patients at high risk of sudden cardiac death. We hypothesised that postextrasystolic potentiation is the main determinant of the regulation patterns of blood pressure (BP) and HR following a PVC. Twelve patients with idiopathic dilated cardiomyopathy (IDC) and 13 control subjects with single PVCs (comparable coupling intervals) were investigated. Non-invasive finger arterial BP and ECGs were analysed. Regulation patterns following a single PVC were quantified using the indices postextrasystolic amplitude potentiation (PEAP) and maximum turbulence slope of five consecutive mean BP values (MBP-TS), and compared with the HR turbulence parameters turbulence slope (HR-TS) and turbulence onset (HR-TO). PEAP was significantly higher in IDC patients compared to controls (48.7 ± 32.6 vs. 9.8 ± 5.4 %, P < 0.01), whereas MBP-TS was lower (0.97 ± 0.60 vs. 2.07 ± 1.04 mmHg BBI−1 (BBI, beat-to-beat interval), P < 0.05), as was HR-TS (8.46 ± 7.90 vs. 30.73 ± 22.90 ms BBI−1, P < 0.01). HR-TO was significantly higher in IDC patients (−0.56 ± 2.19 vs. −5.52 ± 4.13 %, P < 0.01). In addition, the regulation patterns of BP and HR following a single PVC differed significantly between IDC patients and controls. Specifically, we observed pronounced PEAPs in IDC patients. The baroreflex response initiated by the low pressure amplitude of the PVC was suppressed in IDC patients due to the augmented potentiation of the first postextrasystolic blood pressure. Furthermore, IDC patients displayed impressive postextrasystolic pulsus alternans phenomena, whereas healthy subjects exhibited a typical baroreflex pattern. The pulsus alternans phenomenon seems to be triggered by a PVC.  相似文献   
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To investigate the diagnostic and prognostic value of nuclear morphometry in squamous cell carcinomas (SCCs) of canine skin, histological samples from 15 dogs were retrospectively analysed by computerized nuclear morphometry. In each case, the nuclei of at least 100 neoplastic cells were measured, and the mean nuclear area (MNA), standard deviation of MNA (SDa), mean nuclear perimeter (MNP), standard deviation of MNP (SDp), nuclear form factor (FF), and standard deviation of FF (SDf) were calculated. The morphometric data were examined in relation to tumour histological grade. No statistical differences were found between the different grades of SCC in terms of the mean values of SDa, SDp, FF or SDf. The MNA values, however, differed significantly between grades: I and III; I and IV; II and III; II and IV. The MNP values differed significantly between grades: I and III; I and IV; II and IV. The results indicate that nuclear morphometry analysis is a simple and reproducible method that could be used to provide objective diagnostic criteria for cutaneous SCCs in the dog.  相似文献   
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The expression of the beta1 common chain of the VLA integrin subfamily was evaluated immunohistochemically in a series of five normal and 30 neoplastic canine testicles. The tumours, consisting of seminomas or Sertoli cell tumours, were classified according to WHO criteria as intraductal without signs of invasion, intraductal with signs of invasion, or diffuse. Expression of beta1 integrin decreased progressively from intraductal tumours without signs of invasion, to the diffuse type, in which immunolabelling was generally absent. In a few cases of diffuse neoplasia, groups of neoplastic cells exhibited strong positivity that was not restricted to the basal pole of the cell membrane. These results suggest that the expression of beta1 integrin was related to the histological tumour type, possibly reflecting a specific requirement for a reduction in integrin by neoplastic cells with infiltrative and metastatic potential.  相似文献   
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In a previous study we demonstrated that MG-63 cells cultured on Ti-6Al-4V discs covered by alumina ceramic and submitted to intermittent mechanical strain (IMS) presented morphological alteration associated with enhanced differentiation. Here we examine how the mechanical response of osteoblasts can be modulated by the nature of the substrate. MG-63 cells were cultured on four materials: polystyrene and Ti-6Al-4V (average roughness = 0.48 microm) as smooth substrates; Ti-6Al-4V (average roughness = 5.76 microm) and Ti-6Al-4V covered with alumina (average roughness = 5.21 microm) as rough substrates. Mechanical strains were applied for 15 min, three times a day for 1-5 days with a 600 microstrains magnitude and a 0.25 Hz frequency. IMS stimulated alkaline phosphatase activity by 25-35% on all substrates and had no effect on cell growth on either substrate. Fibronectin (FN) was chosen as representative of cell-matrix interaction. FN production was increased by 60% after 1 day of stretching only on alumina-coated discs. FN organization examined on smooth substrates was affected by 5 days of IMS, showing a thickening of the fibres. The same modifications induced by IMS were previously observed on alumina-covered discs. Vinculin expression was not affected by IMS whatever the substrate. Cell-cell interactions were determined by N-cadherin immunoblotting. N-cadherin expression was increased by IMS specifically on rough substrates. Our results suggest that the nature of the surface did not influence the up-regulation of alkaline phosphatase activity induced by IMS, but modulates specifically cell-substrate as well as cell-cell interactions in response to IMS.  相似文献   
9.
Summary To specify the exercise-induced changes on different skeletal sites, the effect of a 5-week endurance swin training was studied in rats. Eighteen Lyon strain (Sprague-Dawley) 5-week old female rats were divided into nine sedentary and nine swimming rats. Each swim training session was increased by 15 minutes from 2–6 hours per day. A histomorphometric study was performed at the primary and secondary spongiosa of the distal femur and at the secondary spongiosa of lumbar and thoracic vertebral bodies. After training, bone loss was observed in the secondary spongiosa of lumbar vertebral bodies (24.7%) and in the primary spongiosa of distal femur (15.2%). A tendency to bone loss was also detected in the secondary spongiosa of distal femur (10.8%), whereas no change was detected in thoracic vertebral bodies. In secondary spongiosa, bone loss was accompanied with a thinning of trabeculae. Total eroded surfaces and osteoid surfaces were significantly decreased in the three studied skeletal sites, suggesting a decreased bone turnover. The decreased thickness of osteoid seams in both lumbar vertebrae and distal femur could mean that the osteoblastic activity has also been altered at the cell level, leading to thinning of trabeculae. Five-week swim training with such duration and intensity of exercise appears unable to increase bone volume in rats and, therefore, causes adverse effects. The three studied bones seemed to adapt differently to experimental conditions. The lack of ground reaction forces induced by water immersion might have contributed to the observed bone loss. Normal gravity would be an important cofactor in the osteogenic effects of exercise.  相似文献   
10.
Bone mineral density (BMD) was measured in 128 normal postmenopausal women at different skeletal sites: lumbar spine and proximal femur, using dual-energy X-ray absorptiometry (DXA), and the cancellous and cortical envelopes of the distal third of radius and tibia, using precise low-dose quantitative computed tomography (QCT). Multivariate analysis included chronological age, ages related to menstrual history (menopause and menarche) and anthropometric factors, e.g. height and weight, as independent predictive variables. Weight is a much-studied predictor of bone density. At sites of high bone turnover, i.e. cancellous envelope, the effect of weight appeared overshadowed by estrogen-related parameters: age-past-menopause was the first predictor of BMD in the cancellous compartment of radius and in Ward's triangle, and the number of reproductive years was the strongest predictor of BMD in the cancellous compartment of tibia and in the spine (L2–4). This suggests that in addition to menopause, the length of menstrual life should be considered as an explanation for the variations in current bone mass in postmenopausal women.At the cortical level of radius, the effect of chronological age was predominant. At the cortical level of tibia, height and weight were the best predictors of BMD.We conclude that the influence of parameters related to menstrual history is predominant in sites with mainly cancellous tissue and that anthropometric factors constitute the best predictors of BMD in the cortical sites of weight-bearing bones.  相似文献   
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