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【单选题】
《安全生产法》规定了生产经营单位必须为从业人员提供符合国家标准或者( )的劳动保护用品，并监督、教育从业人员按照使用规则佩戴、使用。
A.
国际标准
B.
地方标准
C.
企业标准
D.
行业标准
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参考答案：
举一反三
【判断题】临床上评估眼动的目的是因为它与阅读关系密切
A.
正确
B.
错误
查看完整题目与答案
【判断题】The tissue-cell specificity of biological development is based on the fact that cells in different tissues have different genomes.
A.
正确
B.
错误
查看完整题目与答案
【判断题】显微镜观察酵母和青霉,只能用低倍镜观察
A.
正确
B.
错误
查看完整题目与答案
【多选题】How do different types of muscle cells perform different functions?
A.
The highly specialized contractile machinery in muscle cells is thought to have evolved from the simpler contractile bundles of myosin and actin filaments found in all eukaryotic cells. The myosin-II in nonmuscle cells is also activated by a rise in cytosolic Ca 2+ , but the mechanism of activation is different from that of the muscle-specific myosin-II. An increase in Ca 2+ leads to the phosphorylation of nonmuscle myosin-II, which alters the myosin conformation and enables it to interact with actin.
B.
A similar activation mechanism operates in smooth muscle, which is present in the walls of the stomach, intestine, uterus, and arteries, and in many other structures that undergo slow and sustained involuntary contractions. This mode of myosin activation is relatively slow, because time is needed for enzyme molecules to diffuse to the myosin heads and carry out the phosphorylation and subsequent dephosphorylation.
C.
However, this mechanism has the advantage that—unlike the mechanism used by skeletal muscle cells—it can be activated by a variety of extracellular signals: thus smooth muscle, for example, is triggered to contract by epinephrine, serotonin, prostaglandins, and several other signal molecules.
D.
In addition to skeletal and smooth muscle, other forms of muscle each perform a specific mechanical function. Heart—or cardiac—muscle, for instance, drives the circulation of blood. The heart contracts autonomously for the entire life of the organism—some 3 billion (3 × 10 9 ) times in an average human lifetime. Even subtle abnormalities in the actin or myosin of heart muscle can lead to serious disease. For example, mutations in the genes that encode cardiac myosin-II or other proteins in the sarcomere cause familial hypertrophic cardiomyopathy, a hereditary disorder responsible for sudden death in young athletes.
查看完整题目与答案
【多选题】根据依法治国的要求 , 我们中职学生应该做到 ( )
A.
依法行政
B.
积极学习法律知识
C.
严格遵守法律
D.
勇 于同违法行为做斗 争
查看完整题目与答案
【判断题】Cells have different structures and functions, because their chemical composition are different.
A.
正确
B.
错误
查看完整题目与答案
【简答题】已知集合 A={x| 2x-1 x+1 ≤1，x∈R} ，集合B={x||x-a|≤1，x∈R}． （1）求集合A； （2）若B∩? R A=B，求实数a的取值范围．
查看完整题目与答案
【单选题】据赵岐所言, 《孟子》 “传记博士”设置于( )时期。
A.
汉高祖
B.
汉文帝
C.
汉景帝
D.
汉武帝
查看完整题目与答案
【简答题】请仔细阅读下面材料，并详细写出检索思路。 小王是我的好哥们儿，他是北大的高材生，也是一个崇尚完美主义的人，用小王的话说“这和我的血型有关，没办法”。小丽是个漂亮的女生，和小王又是大学同学。经过小王不懈的努力，终于把小丽追到了手。可相处了一段才发现小丽是一个占有俗很强的女人。每每小王提前这事，小丽就会用小王的话反驳他“这也和我的血型有关，而且我这个血型在四种血型中占有欲最强。没办法”。不过幸好小王...
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【多选题】确定企业资本结构时( )。
A.
如果企业的销售不稳定，则可较多的筹措负债资金
B.
为了保证原有股东的绝对控制权，一般应尽量避免普通股筹资
C.
若预期市场利率会上升，企业应尽量利用短期负债
D.
所得税率越高，举借负债利益越明显
查看完整题目与答案
相关题目：
【判断题】临床上评估眼动的目的是因为它与阅读关系密切
A.
正确
B.
错误
查看完整题目与答案
【判断题】The tissue-cell specificity of biological development is based on the fact that cells in different tissues have different genomes.
A.
正确
B.
错误
查看完整题目与答案
【判断题】显微镜观察酵母和青霉,只能用低倍镜观察
A.
正确
B.
错误
查看完整题目与答案
【多选题】How do different types of muscle cells perform different functions?
A.
The highly specialized contractile machinery in muscle cells is thought to have evolved from the simpler contractile bundles of myosin and actin filaments found in all eukaryotic cells. The myosin-II in nonmuscle cells is also activated by a rise in cytosolic Ca 2+ , but the mechanism of activation is different from that of the muscle-specific myosin-II. An increase in Ca 2+ leads to the phosphorylation of nonmuscle myosin-II, which alters the myosin conformation and enables it to interact with actin.
B.
A similar activation mechanism operates in smooth muscle, which is present in the walls of the stomach, intestine, uterus, and arteries, and in many other structures that undergo slow and sustained involuntary contractions. This mode of myosin activation is relatively slow, because time is needed for enzyme molecules to diffuse to the myosin heads and carry out the phosphorylation and subsequent dephosphorylation.
C.
However, this mechanism has the advantage that—unlike the mechanism used by skeletal muscle cells—it can be activated by a variety of extracellular signals: thus smooth muscle, for example, is triggered to contract by epinephrine, serotonin, prostaglandins, and several other signal molecules.
D.
In addition to skeletal and smooth muscle, other forms of muscle each perform a specific mechanical function. Heart—or cardiac—muscle, for instance, drives the circulation of blood. The heart contracts autonomously for the entire life of the organism—some 3 billion (3 × 10 9 ) times in an average human lifetime. Even subtle abnormalities in the actin or myosin of heart muscle can lead to serious disease. For example, mutations in the genes that encode cardiac myosin-II or other proteins in the sarcomere cause familial hypertrophic cardiomyopathy, a hereditary disorder responsible for sudden death in young athletes.
查看完整题目与答案
【多选题】根据依法治国的要求 , 我们中职学生应该做到 ( )
A.
依法行政
B.
积极学习法律知识
C.
严格遵守法律
D.
勇 于同违法行为做斗 争
查看完整题目与答案
【判断题】Cells have different structures and functions, because their chemical composition are different.
A.
正确
B.
错误
查看完整题目与答案
【简答题】已知集合 A={x| 2x-1 x+1 ≤1，x∈R} ，集合B={x||x-a|≤1，x∈R}． （1）求集合A； （2）若B∩? R A=B，求实数a的取值范围．
查看完整题目与答案
【单选题】据赵岐所言, 《孟子》 “传记博士”设置于( )时期。
A.
汉高祖
B.
汉文帝
C.
汉景帝
D.
汉武帝
查看完整题目与答案
【简答题】请仔细阅读下面材料，并详细写出检索思路。 小王是我的好哥们儿，他是北大的高材生，也是一个崇尚完美主义的人，用小王的话说“这和我的血型有关，没办法”。小丽是个漂亮的女生，和小王又是大学同学。经过小王不懈的努力，终于把小丽追到了手。可相处了一段才发现小丽是一个占有俗很强的女人。每每小王提前这事，小丽就会用小王的话反驳他“这也和我的血型有关，而且我这个血型在四种血型中占有欲最强。没办法”。不过幸好小王...
查看完整题目与答案
【多选题】确定企业资本结构时( )。
A.
如果企业的销售不稳定，则可较多的筹措负债资金
B.
为了保证原有股东的绝对控制权，一般应尽量避免普通股筹资
C.
若预期市场利率会上升，企业应尽量利用短期负债
D.
所得税率越高，举借负债利益越明显
查看完整题目与答案
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