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51.
The potential of oral exposure to dolomite, a natural product that contains calcium and magnesium, to initiate teratogenesis was analyzed in Wistar rats. Animals received dolomite oral dosages of 500 and 1500mg/kg during the period of gestation from day 6-15 post conceptionem (p.c.). Maternal, embryo and fetal toxicity were evaluated. Dolomite exposure did not produce maternal toxicity assessed by clinical observations, body weight gain, hematology parameters and relative organs weight. Signs of embryo-fetal toxicity were not observed. Skeletal malformations and visceral variations were similar in control and dolomite-treated groups. On the other hand, slight increase was observed in fetal body weight in the dolomite-treated group. Treatment with dolomite resulted in significantly decreased incidences of unossified xiphisternum, incomplete ossification of xiphisternum and sternebrae. These effects could be caused by a beneficial influence of calcium and magnesium salts present in dolomite on ossification process. In conclusion, in this study we found that the oral exposure to rats of up to 1500mg/kg of dolomite during organogenesis did not induce significant maternal and embryo-fetal toxicity.  相似文献   
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There are no identified biomarkers that could predict response to antiangiogenic or traditional chemoimmunotherapy in metastatic melanoma. We hypothesized that soluble angiogenic factor receptors might help us to identify patients responsive to treatment. A series of 48 patients with stage IV melanoma participating in two phase II clinical trials were included. The trials included treatment with carboplatin, vinorelbine, and subcutaneous interleukin-2 (n=22) or treatment with bevacizumab, dacarbazine, and low-dose interferon-α2a (n=26).Serum samples were prospectively collected and soluble vascular endothelial growth factor receptor 1 (s-VEGFR-1) and 2 (s-VEGFR-2) were measured before starting the trial treatment and during response evaluation.There was a trend toward longer overall survival among patients with higher-than-median serum VEGFR-1 levels (21.3 months) compared with 12.3 months in patients with low pretreatment s-VEGFR-1 levels (P=0.146). Pretreatment s-VEGFR-2 levels did not correlate to survival. Serum VEGFR-2 levels decreased during therapy in 44% of the patients and increased in 56% of the patients. VEGFR-2 increased in 78% (14 of 18) of the patients who progressed during therapy (P=0.017). VEGFR-2 decrease was associated with clinical benefit in 65% of the patients (11 of 17) and with progression in only four patients (P=0.016).High pretreatment levels of s-VEGFR-1 are associated with improved prognosis among patients with metastatic melanoma independently on therapy, whereas increased VEGFR-2 levels during therapy are associated with disease progression. These markers might be useful in selecting patients responsive to antiangiogenic therapy.  相似文献   
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Objective: The left atrial appendage is a significant source of cardioembolic thrombi. Open mitral valve surgery presents an opportune time to exclude this appendage from cardiovascular circulation. However, sparse randomized trial support exists for this concomitant procedure. We therefore designed a randomized controlled trial to assess the short- and long-term outcomes of concomitant left atrial appendage exclusion. This report details early outcomes of the pilot trial. Methods: Forty-three patients were randomized to either undergo concomitant suture exclusion of their left atrial appendage under direct vision or not during their open mitral valve surgery. Clinical and biochemical postoperative outcomes, including hemodynamic and hemostatic parameters, were analyzed. Results: There were no deaths in either group. The incidence of cerebrovascular events, myocardial infarction, respiratory failure, and acute renal injury were similar between groups; a composite outcome of 10 major postoperative complications occurred in 32% of the left atrial appendage exclusion group versus 38% of the control group (p = 0.75). Intensive care (median stay 2 days vs 1 day in the control group, p = 0.55) and hospital lengths of stay (median stay 9 days in both groups, p = 0.98) were also similar between groups. Specifically, no additional hemodynamic alterations (need for intra-aortic balloon pump in 1 vs 2 patients in the control group, p = 0.61) or hemostatic complications (no re-operations for bleeding in either group, need for blood product transfusion in 2 vs 1 patient in the control group, p = 1.0) were noted in the left atrial appendage exclusion group. Conclusions: This pilot trial demonstrates the safety of and feasibility of a larger trial powered to detect clinically relevant short- and long-term outcomes of concomitant left atrial appendage exclusion with open mitral valve surgery.  相似文献   
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