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Summary Previous studies of Alcian blue-induced birefringence in adult avian cortical bone showed that a short period of intermittent loading rapidly produces an increased level of orientation of proteoglycans within the bone tissue. In the absence of further loading, this persists for over 24 hours. We have proposed that this phenomenon could provide a means for “capturing” the effects of transient strains, and so provide a persistent, constantly updated strain-related influence on osteocyte populations related to the bones' averaged recent strain history, in effect, a “strain memory” in bone tissue. In our present study, we use the Alcian blue-induced birefringence technique to demonstrate that proteoglycan orientation also occurs after intermittent loading of both cortical and cancellous mammalian bonein vivo andin vitro. We also show that the change in birefringence is proportional to the magnitude of the applied strain, and that the reorientation occurs rapidly, reaching a maximal value after only 50 loading cycles. Examination of electron micrographs of bone tissue after staining with cupromeronic blue allows direct visualization and quantification of the change in proteoglycan orientation produced by loading. This shows that intermittent loading is associated with a realignment of the proteoglycan protein cores, bringing them some 5 degrees closer to the direction of collagen fibrils in the bone matrix.  相似文献   
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Cruciferous vegetables contain glucobrassicin which, during metabolism, yields indole-3-carbinol (I3C). In a low pH environment I3C is converted into polymeric products, among which 3,3'-diindolylmethane (DIM) is the main one. The apoptotic effects of I3C and DIM were exhibited in human breast cancer cells. The objectives of this study were: (a) examination of the potential effects of I3C and DIM on the proliferation and induction of apoptosis in human prostate cancer cell lines with different p53 status; (b) to try to characterise the mechanism(s) involved in these effects. Our results indicate that both indole derivatives suppress the growth of these cells in a dose- and time-dependent manner, by inducing apoptosis. It appears that these indolic compounds may offer effective means against prostate cancer. Induction of apoptosis was p53-independent. Moreover, the indole derivatives employed did not affect the levels of bcl-2, bax and fasL.  相似文献   
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One hundred sixty consecutive patients with histologically confirmed colorectal cancer (advanced disease) without prior chemotherapy were entered in a randomized trial comparing 5-fluorouracil (5-FU) 1,000 mg/m2 intravenously per day for 5 consecutive days in continuous infusion versus cisplatin (CP) 100 mg/m2 on day 1 plus 5-FU as described on days 2 to 6. In both arms, treatment was recycled every 4 weeks. Both groups were well balanced for age, sex, colon or rectal origin, median time between diagnosis to advanced disease, performance status at entry, and visceral involvement. The overall response rate in the combination and in the single arm were 18 and 23%, respectively. There were no differences in time to progression (a median of 17.8 and 14.9 weeks for CP-5-FU and 5-FU, respectively) and in overall survival (a median of 71.2 and 59.6 weeks, respectively). The incidence of grade 3-4 emesis was significantly higher in the CP-containing chemotherapy (p = .00001). Our study has failed to demonstrate any clinical benefit from adding cisplatin to 5-FU in patients with cancer of the colon and rectum.  相似文献   
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To investigate the influence of glucocorticosteroid therapy on the neonatal blood count, the haematologic data of 68 preterm and term infants, who had received a single dose of 1 mg dexamethasone i.v., were reviewed. White blood cell (WBC) count and platelet count increased after steroid therapy. The increase in WBCs was associated with an increase in the number of neutrophilic granulocytes, whereas the number of eosinophils decreased. We conclude that glucocorticosteroids after the neonatal blood count and influence its value as a diagnostic marker for bacterial infections.  相似文献   
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A 58-year-old postmenopausal woman with primary ovarian serous carcinoma presented with the syndrome of inappropriate antidiuresis (SIAD). Preoperative workup showed serum sodium level of 110 mEq/liter and antidiuretic hormone level of 3.3 pg/ml. The serum and urine osmolarity were 239 and 371, respectively. Antidiuretic hormone was demonstrated in tumor cells by immunohistochemistry. To the best of the authors’ knowledge, this represents the first case of SIAD due to primary ovarian tumor.  相似文献   
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