海兰褐蛋鸡眼型大肠杆菌病的诊断和防治

通过实验室微生物学鉴定了一起海兰褐育成蛋鸡“瞎眼病” ,结果表明该病为全眼球炎型大肠杆菌病。该菌株血清型为O2 ,经药敏试验 ,筛选出 4种敏感药物 ,经临床紧急治疗 ,病情得到有效控制。     

U.s. Trade policy at a crossroad

U.S. trade policy since the end of World War II has rested on two pillars: a multilateral approach to trade agreements and a commitment to rules rather than results. Support for each principle is rapidly eroding because of, among other things, record trade deficits and pessimism about the effects of exchange rate movements on trade flows. In fact, however, U.S. trade deficits are largely "homemade," and trade flows are responsive to changes in exchange rates. The U.S. has played a leadership role in promoting freer trade on a multilateral basis. Adoption of any one of a number of recently proposed alternative trade policy frameworks would be counter to that role.