传感器的响应特性必须在所测频率范围内努力保持不失真测试条件。

题型:判断题

问题:

传感器的响应特性必须在所测频率范围内努力保持不失真测试条件。

考点:测试技术测试技术题库
题型:判断题

甲状腺功能亢进的病人的甲状腺

A.寒战发热伴有咳嗽气急、胸痛等症
B.冬春
C.寒热往来,汗出热退,休作有时为特征
D.春夏
E.夏秋

题型:判断题

请分析回答细胞临时装片制作、观察等相关问题:(8分)

⑴制作人口腔上皮细胞临时装片过程中,应先在载玻片中央滴一滴     ;染色时所用的染剂是      

⑵若显微镜的目镜为5×,物镜为40×,则观察到的物像放大       倍。若视野内有污点,移动临时装片和转动目镜后,污点均不动,说明污点在      上。

⑶人口腔上皮细胞结构与右图中的      (填“甲”或“乙”)

相同,判断依据是      。 

                         

⑷无论甲细胞还是乙细胞,遗传信息库都是②     ,该结构中存在染色体,染色体的主要成分是       和蛋白质。

题型:判断题

所有的消毒剂在使用前需要了解其性质和特点,保证产品()。

A.合理使用

B.安全有效

C.保证效果

D.经济合算

题型:判断题

Ⅰ型糖尿病的发病与下列哪些因素有关()

A.遗传

B.病毒感染

C.自身免疫反应

D.饮用牛奶

E.肥胖

题型:判断题

Imagine eating everything delicious you want with none of the fat. That would be great, wouldn’t it

New "fake fat" products appeared on store shelves in the United States recently, but not everyone is happy about it. Makers of the products, which contain a compound called olestra, say food manufacturers can now eliminate fat from certain foods. Critics, however, say the new compound can rob the body of essential vitamins and nutrients and also cause unpleasant side effects in some people. So it’s up to consumers to decide whether the new fat-free products taste good enough to keep eating.

Chemists discovered olestra in the late 1960s, when they were searching for a fat that could be digested by infants more easily. Instead of finding the desired fat, the researchers created a fat that can’t be digested at all.

Normally, special chemicals in the intestines (肠道) "grab" molecules of regular fat and break them down so they can be used by the body. A molecule of regular fat is made up of three molecules of substances called fatty acids.

The fatty acids are absorbed by the intestines and bring with them the essential vitamins A, D, E and K. When fat molecules are present in the intestines with any of those vitamins, the vitamins attach to the molecules and are carried into the bloodstream.

Olestra, which is made from six to eight molecules of fatty acids, is too large for the intestines to absorb. It just slides through the intestines without being broken down. Manufacturers say it’s that ability to slide unchanged through the intestines that makes olestra so valuable as a fit substitute. It provides consumers with the taste of regular fat without any bad effects on the body. But critics say olestra can prevent vitamins A, D, E and K from being absorbed. It can also prevent the absorption of carotenoids (类胡萝卜素), compounds that may reduce the risk of cancer, heart disease, etc.

Manufacturers are adding vitamins A, D, E and K as well as carotenoids to their products now. Even so, some nutritionists are still concerned that people might eat unlimited amounts of food made with the fat substitute without worrying about how many calories they are consuming.

The result of the search for an easily digestible fat turned out to be ()。

A. just as anticipated

B. commercially useless

C. quite unexpected

D. somewhat controversial

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