| COS cell | <cell culture> A cell line derived from the african green monkey and used for transfection and cloning. The cells are simian fibroblasts (CV 1 cells) transformed by SV40 that is deficient in the origin of replication region. They express large T antigen constitutively and if transfected with a vector containing a normal SV40 origin have all the other early viral genes necessary to generate multiple copies of the vector and thus to give very high levels of expression. (04 Jul 1999) |
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| cos site | <molecular biology> A 12-nucleotide bases-long segment of single stranded DNA that exists at both ends of the bacteriophage lambda's double-stranded genome. The two cos sites at the ends of the genome are complementary to one another so that the genome can become circular once the virus has infected a host bacterium. The circular genome can then be duplicated continuously until there are many repeats of it strung together, the cos sites show the virus where to cut them apart right before they are packaged into individual capsids as new progeny viruses ready to infect more host cells. (10 Nov 1998) |
| Hippocrates of Cos | Greek physician, called the "Father of Medicine," circa 460-377 B.C. See: hippocratic facies, hippocratic fingers, hippocratic nails, school, succussion. (05 Mar 2000) |
| absorptive cells of intestine | Cell's on the surface of villi of the small intestine and the luminal surface of the large intestine that are characterised by having microvilli on their free surface. (05 Mar 2000) |
| air cells | Air-containing spaces in the skull. See: pulmonary alveolus. (05 Mar 2000) |
| air cells of auditory tube | Occasional small air cells in the inferior wall of the auditory tube, near the tympanic orifice, communicating with the tympanic cavity. Synonym: cellulae pneumaticae tubae auditivae, air cells of auditory tube. (05 Mar 2000) |
| Alpha cells | Alpha cell's of pancreas or of anterior lobe of hypophysis. (05 Mar 2000) |
| alpha cells of anterior lobe of hypophysis | Acidophil cell's that constitute about 35% of the cell's of the anterior lobe. There are two varieties: one that elaborates somatotropin, another that elaborates prolactin. (05 Mar 2000) |
| alpha cells of pancreas | Cell's of the islets of Langerhans that secrete glucagon. (05 Mar 2000) |
| amniogenic cells | Cell's from which the amnion develops. (05 Mar 2000) |
| anabiotic cells | Cell's that are capable of resuscitation after apparent death; the existence of anabiotic tumour cell's is postulated to explain the recurrence of a cancer after a very long symptomless period following operation. (05 Mar 2000) |
| angioblastic cells | Those cell's in the early embryo from which primitive blood cell's and endothelium develop. (05 Mar 2000) |
| anterior cells | The anterior group of air cells of the ethmoidal sinus's; each sinus communicates with the middle meatus of the nasal cavity. Synonym: sinus ethmoidales anteriores, anterior cells, anterior sinuses, cellulae anteriores. (05 Mar 2000) |
| anterior ethmoidal air cells | The anterior group of air cells of the ethmoidal sinus's; each sinus communicates with the middle meatus of the nasal cavity. Synonym: sinus ethmoidales anteriores, anterior cells, anterior sinuses, cellulae anteriores. (05 Mar 2000) |
| anterior horn cells | Motor neurons in the anterior (ventral) horn of the spinal cord which project to skeletal muscles. (12 Dec 1998) |