问题 单项选择题

穿髓孔内由表及里依次为炎性、坏死渗出,炎性肉芽组织及新生的胶原纤维,有活性的散布炎细胞浸润的牙髓组织的变化见于()

A.急性浆液性牙髓炎

B.急性化脓性牙髓炎

C.慢性闭锁性牙髓炎

D.慢性溃疡性牙髓炎

E.慢性增生性牙髓炎

答案

参考答案:D

解析:试题难度:中;此题为慢性牙髓炎病理变化的分析题。根据普通病理性的知识,出现肉芽组织的炎症一般为慢性炎症,可以排除A、B选项。在慢性牙髓炎中,慢性闭锁性牙髓炎无穿髓孔,故可排除C选项。慢性增生性牙髓炎一般表现为牙髓组织增生充填龋洞,有时其表面尚有复层鳞状上皮覆盖,因此也可排除。慢性溃疡性牙髓炎自穿髓孔处向深部的表现由表及里依次为炎性、坏死渗出,炎性肉芽组织及新生的胶原纤维,有活性的散布炎细胞浸润的牙髓组织。正确答案应为D。

单项选择题
单项选择题

Text 4

The meanings of "science" and "technology" have changed significantly from one generation to another. More similarities than differences, however, can be found between the terms. Both science and technology imply a thinking process, both are concerned with causal relationships in the material world, and both employ an experimental methodology that results in empirical demonstrations that can be verified by repetition. Science, at least in theory, is less concerned with the practicality of its results and more concerned with the development of general laws, but in practice science and technology are inextricably involved with each other. The varying interplay of the two can be observed in the historical development of such practitioners as chemists, engineers, physicists9 astronomers, carpenters, potters, and many other specialists. Differing educational requirements, social status, vocabulary, methodology, and types of rewards, as well as institutional objectives and professional goals, contribute to such distinctions as can be made between the activities of scientists and technologists; but throughout history the practitioners of "pure" science have made many practical as well as theoretical contributions.

Indeed, the concept that science provides the ideas for technological innovations and that pure research is therefore essential for any significant advancement in industrial civilization is essentially a myth. Most of the greatest changes in industrial civilization cannot be traced to the laboratory. Fundamental tools and processes in the fields of mechanics, chemistry,. astronomy, metallurgy, and hydraulics were developed before the laws governing their functions were discovered. The steam engine, for example, was commonplace before the science of thermodynamics elucidated the physical principle underlying its operations.

In recent years a sharp value distinction has grown up between science and technology. Advances in science have frequently had their bitter opponents, but today many people have come to fear technology much more than science. For these people, science may be perceived as a serene, objective source for understanding the eternal laws of nature, whereas the practical manifestations of technology in the modern world now seem to them to be out of control.

Many historians of science argue not only that technology is an essential condition of advanced, industrial civilization, but also that the rate of technological change has developed its own momentum in recent centuries. Innovations now seem to appear at a rate that increase geometrically, without respect to geographical limits or political systems. These innovations tend to transform traditional cultural systems, frequently with unexpected social consequences. Thus technology can be conceived as both a creative and a destructive process.

The "historians" as mentioned in the last paragraph regard the technology with().

A.absolute enthusiasm

B.total indifference

C.obvious resentment

D.reserved approval