Abstract: A rolling device and a measuring device are disclosed. A rolling assembly in the rolling device is movably mounted on a bracket in a first direction (a) parallel to a working surface, and when a member to be rolled is placed on the working surface, the rolling assembly provides a rolling pressure to the member to be rolled. In a rolling process, the rolling assembly moves in the first direction (a), so as to be capable of ensuring that the rolling pressure applied to the member to be rolled is constant and always perpendicular to the member to be rolled, that is, ensuring that the rolling pressure remains constant, thereby reducing the influence of external factors on the rolling process and improving the accuracy of a measurement result.

Abstract: A cordycepin-based derived compound with an anti-tumor effect, and a structure of the compound is as shown in formula I; a cordycepin derivative and a pharmaceutical composition thereof provided by the invention have a good anti-tumor proliferation effect; compared with a parent drug, the cordycepin derivative has better affinity to cell membranes, so that a half-life period of in-vivo metabolism of the drug is longer, and in-vivo remaining time of the drug is longer; compared with other nucleoside anti-tumor drugs, the cordycepin derivative and the pharmaceutical composition thereof provided by the invention have wider types and action ranges of tumors, have excellent inhibition effects on a gastric cancer, a pancreatic cancer, a liver cancer, a small cell lung cancer, a colorectal cancer, melanoma, an ovarian cancer and the like, and have lower side effects and better curative effects.

Abstract: A method for preparing a nitrogen-containing heterocyclic compound and a derivative thereof by an enzymatic-chemical cascade method, comprising: reacting an alcohol, an amine, an alcohol dehydrogenase, a flavin molecule and a coenzyme in a solvent to obtain the nitrogen-containing heterocyclic compound and the derivative thereof; compared with the prior art, the method is a green and economical enzymatic-chemical cascade method, and is used for synthesizing nitrogen-containing heterocyclic compounds and derivatives thereof; compared with a common toxic chemical catalyst, the alcohol dehydrogenase is selected as a catalyst in the method, which has the characteristics of high substrate specificity, no pollution, high catalytic efficiency, no toxic solvents and simple post-treatment.