caffeine造句61. The disruptive effects of alcohol on sleep can be exacerbated by caffeine.
62. Drinking a caffeine-containing beverage in the morning may help also be-cause caffeine constricts cerebral blood vessels.
63. Neurons bathed in modest levels of caffeine respond more vigorously to stimulation and form longer-lasting changes in their connections with other neurons.
64. Women who consume large amounts of caffeine are more likely to give birth to underweight babies.
65. First, since nicotine is a central nervous system stimulant, it produces almost the same effects on the body as caffeine.
66. This now appears to be one way the brain reacts to caffeine.
67. Drink: It is well-known that tea and coffee contain caffeine and that caffeine is a stimulant.
68. Of course, tolerance to very heavy doses of caffeine may be problematic for health reasons.
69. One consequence of this lumpiness is that caffeine is far more selective in its actions than is alcohol.
70. It is theoretically possible that caffeine somehow inhibits parts of the brain, such as the hypothalamus, involved in regulating appetite.
71. Thus, with the exception of water, all of the most popular beverages on earth contain either caffeine or alcohol.
72. Out of this new insight has come a radically improved understanding of how alcohol and caffeine work.
73. Nobody at that time had the slightest idea about how caffeine affected the body.
74. Caffeine has long been used to increase physical endurance, in both humans and animals.
75. By altering the brain, caffeine automatically alters all systems regulated by the brain.
76. This is why caffeine is the active ingredient in many prescription and nonprescription migraine treatments.
77. Regardless of the causative agent, the tremors and twitches experienced by some users of caffeine are usually harmless.
78. It appears that chronic caffeine use may cause up-regulation or down-regulation of other neurotransmitter systems as well.
79. Another well-known effect of caffeine is increased hand tremor, which has been measured in numerous experiments.
80. Some even insert caffeine suppositories before a race in an attempt to provide a sustained dose with no stomach upset.
81. In fact, theobromine is seven times more abundant than caffeine in chocolate-about 130 milligrams in a 1-ounce piece.
82. In short, there is no simple answer to whether caffeine is, or is not, helpful in performing intellectual tasks.
83. When you first stop taking caffeine, you may experience withdrawal symptoms.
84. Some experiments on skeletal-muscle strips have demonstrated that caffeine increases contractions, which might seem to explain some of the twitch phenomena.
85. But people tend to drink caffeine on a regular basis over long periods of time-often the greater part of a lifetime.
86. Mountain Dew -, for instance,[http:///caffeine.html] contains 54 milligrams of caffeine per can.
87. Even if every adenosine receptor in your brain were blocked by caffeine, you could still function.
88. The people consuming the caffeine demonstrated tolerance in several ways.
89. Whether caffeine is the root cause of your insomnia or just a contributing factor, your caffeine consumption needs to be addressed.
90. Not surprisingly, the studies of caffeine tolerance and withdrawal have found wide variations in subject responses.