clock


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Related to clock: analog clock

clock

(klok) a device for measuring time.
biological clock  the physiologic mechanism which governs the rhythmic occurrence of certain biochemical, physiologic, and behavioral phenomena in living organisms.

clock

(klŏk)
n.
1. An instrument other than a watch for measuring or indicating time, especially a mechanical or electronic device having a numbered dial and moving hands or a digital display.
2. A biological clock.
v. clocked, clocking, clocks
v.tr.
To register or record with a mechanical device: clocked the winds at 60 miles per hour.

clock′er n.

CLOCK

A gene on chromosome 4q12 that encodes a ubiquitously expressed human homolog of the mouse clock gene, which forms a heterodimer with ARNTL and activates E-box element transcription of several circadian clock proteins (e.g., PER1 and PER2). CLOCK is highly expressed in the suprachiasmatic nucleus.

Molecular pathology
CLOCK-ARNTL double mutations in the PAS domains result in syngernistic desensitisation to high levels of CRY on repression of CLOCK-ARNTL transcriptional activity of PER1, disrupting circadian rhythmicity.

clock

(klok)
A device for measuring time.

biological clock

1. An internal system in organisms that influences behavior in a rhythmic manner. Functions such as growth, feeding, secretion of hormones, the rate of drug action, the wake-sleep cycle, the menstrual cycle, and reproduction coincide with certain external events such as day and night, the tides, and the seasons. Biological clocks appear to be set by environmental conditions in some animals, but if these animals are isolated from their environment they continue to function according to the usual rhythm. A gradual change in environment does produce a gradual change in the timing of the biological clock. See: circadian; maladaptation to night work; zeitgeber
2. A colloquial term for the decrease in fertility that accompanies aging, particularly as women approach the age of 35.

Patient discussion about clock

Q. How do you wake up in the morning if your narcolepsy is so severe you can't hear the alarm clock, phone ring? biggest problem is sleep paralysis, can't wake up. Late for work, everything, life is suffering because of severity. Have tried ritalin, natural supplements, hypnosis therapy, Provigal, antidepressants, nothing seems to work. Employer thinks it's an excuse, friends are irritated, I'm at my wits end. Life is spent sleeping more than awake.

A. Narcolepsy cannot yet be cured. But EDS and cataplexy, the most disabling symptoms of the disorder, can be controlled in most patients with drug treatment. Often the treatment regimen is modified as symptoms change. For decades, doctors have used central nervous system stimulants-amphetamines such as methylphenidate, dextroamphetamine, methamphetamine, and pemoline-to alleviate EDS and reduce the incidence of sleep attacks. For most patients these medications are generally quite effective at reducing daytime drowsiness and improving levels of alertness. However, they are associated with a wide array of undesirable side effects so their use must be carefully monitored. Common side effects include irritability and nervousness, shakiness, disturbances in heart rhythm, stomach upset, nighttime sleep disruption, and anorexia. For full article: http://www.ninds.nih.gov/disorders/narcolepsy/detail_narcolepsy.htm#120393201 Hope this helps.

More discussions about clock
References in classic literature ?
He consequently sprang up again, re-entered the office, with a turn of his finger set the clock right again, that it might not be perceived the next day that it had been put wrong, and certain from that time that he had a witness to prove his alibi, he ran downstairs and soon found himself in the street.
But this clock's so much before the clock at the Chase, there's no telling what time it'll be when I get here.
It will make no difference," I said : "I can call at the office in the morning and apologize; in the meantime what can be the matter with the clock ?
The great clock has seven faces -- one in each of the seven sides of the steeple -- so that it can be readily seen from all quarters.
And, anon, there strikes the ebony clock which stands in the hall of the velvet.
Oh, children of the Prophet, it is known unto you that a Portuguee dog of a Christian clock mender pollutes the city of Tangier with his presence.
Click, clock, click, clock; with each beat of the strangely shaped wings it jumped Bert upward and caught him neatly again half a second later on the saddle.
At that moment the great clock struck two and another with a shrill tone joined in from the drawing room.
As if the clock hadn't finished striking, and the convulsive little Haymaker at the top of it, jerking away right and left with a scythe in front of a Moorish Palace, hadn't mowed down half an acre of imaginary grass before the Cricket joined in at all!
He grudged every moment of life sleep robbed him of, and before the clock had ceased its clattering he was head and ears in the washbasin and thrilling to the cold bite of the water.
The first sound that told of life and movement revealed the mechanical movement of the clock.
If I took up my position "under the shadow of Saint Paul's," say, at ten that night, I should arrive at the place of meeting with two hours to spare, before the last stroke of the clock marked the beginning of the new month.