Adv Exp Med Biol
-
Review Historical Article
The evolution of the biomedical paradigm in oncology: implications for cancer therapy.
-
Buprenorphine is relatively resistant to reversal by naloxone. We tested the effect of various doses and infusion schemes of naloxone on buprenorphine-induced respiratory depression and compared the data with naloxone-reversal of morphine and alfentanil-induced respiratory depression. ⋯ However, reversal was short-lived. The bell-shaped reversal curve may be related to the existence of two mu-opioid receptor subtypes, one mediating the agonist effects of opioids at low dose, the other mediating antagonistic effects at high dose.
-
Breast cancer is the most common cancer and the second leading cause of cancer death in American women. It was the second most common cancer in the world in 2002, with more than 1 million new cases. Despite advances in early detection and the understanding of the molecular bases of breast cancer biology, about 30% of patients with early-stage breast cancer have recurrent disease. ⋯ Treatment resistance is most commonly seen in such patients. They initially may have a response to different agents, but the responses are not sustained, and, in general, the rates of response to subsequent agents are lower. Table 1 summarizes metastatic breast cancer response rates to single-agent systemic therapy.
-
The myocardium is well protected against chronic hypoxia. In chronic hypoxia stroke volume falls both at rest and on exercise. The fall in stroke volume is associated with reduction in left ventricular dimensions and filling pressure. ⋯ The relative importance of different mechanisms which reduce stroke volume probably depends whether hemodynamics are measured at rest or on exercise. Intervention with sildenafil to ameliorate hypoxic pulmonary vasoconstriction is associated with both an increase in exercise capacity and stroke volume in hypoxia. Whether these have a causal association remains to be demonstrated.