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Female Djungarian hamsters (Phodopus sungorus) have proportionately more adipose tissue in superficial depots than males of similar age and body composition. In both sexes, the proportion in superficial depots increases with increasing fatness. This species may be useful as a model for human obesity because it becomes as obese as modern humans without genetic, surgical or dietary manipulation and the sex differences in adipose tissue distribution resemble those of humans. 相似文献
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John J Doyle Alfred I Neugut Judith S Jacobson Victor R Grann Dawn L Hershman 《Journal of clinical oncology》2005,23(34):8597-8605
PURPOSE: Adjuvant chemotherapy, especially with anthracyclines, is known to cause acute and chronic cardiotoxicity in breast cancer patients. We studied the cardiac effects of chemotherapy in a population-based sample of breast cancer patients aged > or = 65 years with long-term follow-up. PATIENTS AND METHODS: In the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we analyzed treatments and outcomes among women > or = 65 years of age who were diagnosed with stage I to III breast cancer from January 1, 1992 to December 31, 1999. Propensity scores were used to control for baseline heart disease (HD) and other known predictors of chemotherapy, and Cox proportional hazards models were used to estimate the risk of cardiomyopathy (CM), congestive heart failure (CHF), and HD after chemotherapy. RESULTS: Of 31,748 women with stage I to III breast cancer, 5,575 (18%) received chemotherapy. Chemotherapy was associated with younger age, fewer comorbidities, hormone receptor negativity, multiple primary tumors, and advanced disease. Patients who received chemotherapy were less likely than other patients to have pre-existing HD (45% v 55%, respectively; P < .001). The hazard ratios for CM, CHF, and HD for patients treated with doxorubicin (DOX) compared with patients who received no chemotherapy were 2.48 (95% CI, 2.10 to 2.93), 1.38 (95% CI, 1.25 to 1.52), and 1.35 (95% CI, 1.26 to 1.44), respectively. The relative risk of cardiotoxicity among patients who received DOX compared with untreated patients remained elevated 5 years after diagnosis. CONCLUSION: When baseline HD was taken into account, chemotherapy, especially with anthracyclines, was associated with a substantially increased risk of CM. As the number of long-term survivors grows, identifying and minimizing the late effects of treatment will become increasingly important. 相似文献
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Dawn Stacey RN MScN CON Annette M. O'Connor RN PhD † Cathy DeGrasse RN MScN ‡ Shailendra Verma MD FRCP § 《Health expectations》2003,6(1):3-18
Objective To develop and evaluate the effectiveness of a breast cancer prevention decision aid for women aged 50 and older at higher risk of breast cancer. Design Pre‐test–post‐test study using decision aid alone and in combination with counselling. Setting Breast Cancer Risk Assessment Clinic. Participants Twenty‐seven women aged 50–69 with 1.66% or higher 5‐year risk of breast cancer. Intervention Self‐administered breast cancer prevention decision aid. Main outcome measures Acceptability; decisional conflict; knowledge; realistic expectations; choice predisposition; intention to improve life‐style practices; psychological distress; and satisfaction with preparation for consultation. Results The decision aid alone, or in combination with counselling, decreased some dimensions of decisional conflict, increased knowledge (P < 0.01), and created more realistic expectations (P < 0.01). The aid in combination with counselling, significantly reduced decisional conflict (P < 0.01) and psychological distress (P < 0.02), helped the uncertain become certain (P < 0.02), and increased intentions to adopt healthier life‐style practices (P < 0.03). Women rated the aid as acceptable, and both women and practitioners were satisfied with the effect it had on the counselling session. Conclusion The decision aid shows promise as a useful decision support tool. Further research should compare the effect of the decision aid in combination with counselling to counselling alone. 相似文献
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The characteristics of the binding sites for 2-[125I]iodomelatonin were studied in chicken brain membranes during development. Specific binding, defined using cold melatonin (1 microM), was detected as early as 8-day-old embryos. Scatchard analysis of saturation experiments showed that 2-[125I]iodomelatonin binds to a single class of site at all ages tested (8-day-old embryos to 3-month-old chicks). Binding affinity (Kd) did not change during development (18-31 pM), but the maximal number of binding sites (Bmax) increased until embryonic day 18, and then remained relatively constant until 30 days of age. A further increase in Bmax was seen at 3 months of age. Guanosine 5'-triphosphate (GTP, 1 mM) inhibited 2-[125I]iodomelatonin binding at all ages suggesting that the melatonin binding site is coupled to a guanine nucleotide binding protein at a very early stage of development. Competition experiments with a number of melatonin analogues indicated that the binding site detected in the brain at embryonic day 8 was pharmacologically identical to that observed 15 days after hatching. 相似文献
48.
Reversal of fulminant hepatic failure using an extracorporeal liver assist device. 总被引:20,自引:0,他引:20
N L Sussman M G Chong T Koussayer D E He T A Shang H H Whisennand J H Kelly 《Hepatology (Baltimore, Md.)》1992,16(1):60-65
Liver transplantation is currently the only effective therapy for patients with fulminant hepatic failure. The availability of an artificial liver could bridge these patients through the relatively brief crisis period and allow their own livers to regenerate, providing a more favorable outcome and sparing the trauma and expense of transplant. We have developed a device consisting of a highly differentiated human liver cell line cultured in a hollow fiber cartridge. This device is capable of supporting dogs with acetaminophen-induced fulminant hepatic failure for a period long enough for their own livers to resume function. Even though liver function tests such as albumin and prothrombin time became extremely abnormal during the course of the experiment, the dogs did not become encephalopathic. Two of the three treated animals recovered sufficient liver function after 42 to 48 hr of treatment that they could be disconnected from the device, and they survived the experiment. Histological results and serum ALT levels suggest that the device affected the course of the disease in two animals, allowing recovery of hepatocytes that would otherwise have lysed. In the third animal, regenerative nodules demonstrated that, even in the presence of severe liver injury, the device was capable of supporting total liver function. 相似文献
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异丙酚及氯胺酮靶控输注全静脉麻醉临床应用 总被引:4,自引:1,他引:3
目的 研究异丙酚复合不同镇痛剂量氯胺酮靶控输注全静脉麻醉临床应用的可行性及对血流动力学、麻醉恢复的影响。方法 择期手术患者 80例 ,分别采用异丙酚 (P组 ,n =16)及复合氯胺酮血药浓度 0 2 0mg/L(PK1组 ,n =16) ,0 40mg/L(PK2 组 ,n =16) ,0 60mg/L(PK3 组 ,n =16)和 0 80mg/L(PK4组 ,n =16)全静脉麻醉 ,采用微机控制Graseby 3 5 0 0输液泵靶控输注异丙酚或氯胺酮 ,连接Aspect-A10 0 0型脑电监护仪监测脑电变化 ,观察两组患者血流动力学改变及麻醉恢复情况。结果 单用异丙酚患者随着异丙酚血药浓度升高脑电双频指数 (BIS)值降低 ,呈明显负相关 (P <0 0 5 ) ,氯胺酮血药浓度从 0 2 0mg/L增至 0 80mg/L ,BIS值无明显变化 (P >0 0 5 )。与P组相比 ,PK1,PK2 ,PK3 ,PK4组异丙酚用量减少约 15 %~ 40 % ,PK4组停药至睁眼时间明显延长 ,其余各组无明显差异 (P >0 0 5 )。术中P ,PK1组收缩压、舒张压升高 ,PK2 ,PK3 ,PK4组无明显改变。术后无躁动、不良回忆等并发症。结论 异丙酚复合镇痛剂量的氯胺酮 (0 40~ 0 60mg/L)靶控输注全静脉麻醉具有血流动力学稳定、减少异丙酚用量、无明显术后并发症等优点。 相似文献