阿糖胞苷的化学结构为（ ）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/588c9b478695464b9617893b2e1c303a.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/86b60f7b512f43a29c8431f882722d1b.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/4546ccb30ea64350a626b0cd337e2c98.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/8f610edce6dd4a2e81ca814690e0b5ec.png" />

下列关系正确的有（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/0c9a6360c85f4ff9bdb2b17b576df2e0.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/09c3ca64214040d89eaa8534fa21d895.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/3d88f37ec20c4604a8387c0e1088ad34.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/d48f61b369aa425384b1d565afb5d073.png" />

具有顺反异构体的物质是 ( ) 。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/9bf08e194cf24f80b9582238a48b2d98.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/6a33a313aebe4d5a8d8f6cd250361fec.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/f7a33598bdb74c3180f03e2517cac29c.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/d86d498d7c6b4594ad58fdbaad86028c.png" />

下列最稳定的自由基是（ ）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/7ff51d95af804e74bbffb2091d336668.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/a7bc08ef90914e13a5f795670eb1e67b.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/6f85cd60c27645c39d58990b87615ebf.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/f5d0c506ba09424a838f7aee98e94e43.png" />

属于钙通道阻滞剂的药物是（ ）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/3112081992ed47f8bf358bd9942d5ebb.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/17c349ff9e8e450c971ceb98947611f8.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/4194526443744627b8a6fc1be47523d1.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/28cffdd18be74b33bc7d9efac912d8c3.png" />

下列函数表达中，（ ）是周期信号（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/fa28c4df306a4768855eadcf32f77987.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/7a1a43bddcbc4b438f49428cef75ea64.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/5b67d7d31dd34862904bc3d9086668ed.jpg" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/377afdab17404edf84b525cd9e974df1.png" />

下列4个推理定律中，正确的是（ ） A: <img src="https://image.zhihuishu.com/zhs/aidedteaching/demo/202012/bc426d3543dc409db074154a64afb5c9_s1.jpg"> B: <img src="https://image.zhihuishu.com/zhs/aidedteaching/demo/202012/d89869317df9433caa1c066f3c7d7f26_s1.jpg"> C: <img src="https://image.zhihuishu.com/zhs/aidedteaching/demo/202012/b9c4b0574b5244e38513d3395f3209b6_s1.jpg"> D: <img src="https://image.zhihuishu.com/zhs/aidedteaching/demo/202012/0b2df5df8a754a2383c1b9366b86f127_s1.jpg">

下列哪些模板可用于图像锐化？（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/f0462578b67a4958b63a36ee38d41bce.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/b58edf54767842408a9b4d5e8d9ef230.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/13b381992b7f4fdb8b79ab32b879c121.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/e915aa28bbd54e38b76311ed86333ad1.png" />

以下属于二向应力状态的是（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/e15f6476f10340b08e04f43932434268.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/e15f6476f10340b08e04f43932434268.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/e15f6476f10340b08e04f43932434268.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/e15f6476f10340b08e04f43932434268.png" />

下列化合物中，有顺反异构的是（ ）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/4caea8e88bac45b48d41bb2b16eacd0d.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/51411268d61c4efeb122a51094211c7c.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/3dc98c0e8e694c4a8c7b75033743aec1.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202012/a2f358ca8faa4ba5904624989c0ca9b7.png" />