C203顶压高,可能是因为() ["A、重石抽出量变化","B、航煤抽出量变化","C、轻石抽出量变化","D、进料带水"]
四冲程柴油机压缩冲程所占的曲柄转角等于() ["180°-进气提前角","180°+进气提前角","180°+进气延迟角","180°-进气延迟角"]
男性,28岁。因反复腹痛、腹泻2年入院。胃肠钡餐造影见回肠末端呈线样征、易激惹。最可能的诊断是() ["溃疡性结肠炎","肠结核","克隆病","肠粘连","回肠末端肿瘤"]
四冲程柴油机的以下四个冲程过程中,占曲柄转角大于180度的过程是() ①进气冲程 ②压缩冲程 ③膨胀冲程 ④排气冲程 ["①②","②③","①④","②④"]
下述哪项最有助于鉴别细菌性痢疾和溃疡性结肠炎() ["有无里急后重","有无腋脓血便","有无便血","抗生素治疗是否有效","有无发热"]
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