| ELT | endless loop tachycardia; euglobulin lysis time |
|---|---|
| FVL | femoral vein ligation; flow volume loop; force, velocity, length |
| LEEP | left end-expiratory pressure; loop electrosurgical excision procedure |
| LLETZ | large loop excision of the transformation zone |
| LOH | loop of Henle; loss of heterozygosity |
| loop electrocautery excision procedure | Electrocautery excisional biopsy of abnormal cervical tissue. (05 Mar 2000) |
|---|---|
| loop excision | A diagnostic and therapeutic gynecological surgical technique for removing dysplastic cells from the cervix. In this office procedure conducted with the aid of colposcopy, a small wire loop is used to excise visible patches of cervical intraepithelial neoplasia. Like cauterization, cryosurgery, and CO2 laser procedures, loop excision can be done with local anaesthetic, and is an uncomplicated, relatively inexpensive way of removing dysplastic cells; in addition, it provides material for biopsy. It is not advised for cases of severe dysplasia or carcinoma in situ, which are better addressed by cervical conization, an inpatient procedure. Synonym: loop resection. (05 Mar 2000) |
| loop of henle | A u-shaped turn in the medullary portion of a renal tubule, with a descending limb from the proximal convoluted tubule and an ascending limb to the distal convoluted tubule. (12 Dec 1998) |
| loop of hypoglossal nerve | A loop in the cervical plexus consisting of fibres from the first three cervical nerves. Fibres from a loop between the C-1 and C-2 spinal nerves accompany the hypoglossal nerve for a short distance, leaving it as the superior root of the ansa cervicalis. Fibres from a loop between the C-2 and C-3 spinal nerves form the inferior root of the ansa cervicalis. Most commonly, the roots merge, forming the ansa cervicalis, which gives rise to branches innervating infrahyoid muscles. Synonym: cervical loop, loop of hypoglossal nerve. (05 Mar 2000) |
| loop resection | A diagnostic and therapeutic gynecological surgical technique for removing dysplastic cells from the cervix. In this office procedure conducted with the aid of colposcopy, a small wire loop is used to excise visible patches of cervical intraepithelial neoplasia. Like cauterization, cryosurgery, and CO2 laser procedures, loop excision can be done with local anaesthetic, and is an uncomplicated, relatively inexpensive way of removing dysplastic cells; in addition, it provides material for biopsy. It is not advised for cases of severe dysplasia or carcinoma in situ, which are better addressed by cervical conization, an inpatient procedure. Synonym: loop resection. (05 Mar 2000) |
| a helix | The helical (commonly right-handed) form present in many proteins, deduced by Pauling and Corey from X-ray diffraction studies of proteins such as alpha-keratin; the helix is stabilised by hydrogen bonds between, e.g., ==C==O and HN== groups (symbolised by the centre dot in ==CO-HN==) of different eupeptide bonds. In a true a helix, there are 3.6 amino acid residues per turn of the helix. Synonym: 3.613 helix, Pauling-Corey helix. Collagen helix, an extended left-handed helix resulting from the high levels of glycine, l-proline, and l-hydroxyproline present in the collagens. There are 3.3 amino acids per turn of the helix. Three of those left-handed helices form a triple superhelix that is right-handed. (05 Mar 2000) |
| alpha helix | <molecular biology> A particular helical folding of the polypeptide backbone in protein molecules (both fibrous and globular), in which the carbonyl oxygens are all hydrogen bonded to amide nitrogen atoms three residues along the chain. The translation of amino acid residues along the long axis is 0.15 nm and the rotation per residue, 100 |
| Pauling-Corey helix | The helical (commonly right-handed) form present in many proteins, deduced by Pauling and Corey from X-ray diffraction studies of proteins such as alpha-keratin; the helix is stabilised by hydrogen bonds between, e.g., ==C==O and HN== groups (symbolised by the centre dot in ==CO-HN==) of different eupeptide bonds. In a true a helix, there are 3.6 amino acid residues per turn of the helix. Synonym: 3.613 helix, Pauling-Corey helix. Collagen helix, an extended left-handed helix resulting from the high levels of glycine, l-proline, and l-hydroxyproline present in the collagens. There are 3.3 amino acids per turn of the helix. Three of those left-handed helices form a triple superhelix that is right-handed. (05 Mar 2000) |
| groove of crus of the helix | A transverse fissure on the cranial surface of the auricle corresponding to the crus of the helix. Synonym: sulcus cruris helicis. (05 Mar 2000) |
| pi helix | A rare right-handed helix found only in small portions of certain proteins. Stabilised by similar hydrogen bonds as in an a helix; there are 4.3 amino acid residues per turn of the helix. (05 Mar 2000) |
| Watson-Crick helix | The helical structure assumed by two strands of deoxyribonucleic acid, held together throughout their length by hydrogen bonds between bases on opposite strands, referred to as Watson-Crick base pairing. See: base pair. Synonym: DNA helix, double helix, twin helix. (05 Mar 2000) |
| muscle of notch of helix | An occasional muscle on the cranial surface of the auricle spanning the antitragohelicine fissure. Synonym: musculus incisurae helicis, musculus intertragicus. (05 Mar 2000) |
| crus of helix | A transverse ridge continuing backward from the helix of the auricle, dividing the concha into an upper portion (cymba) and a lower portion (cavity of concha). Synonym: crus helicis, crista helicis, limb of helix. (05 Mar 2000) |
| helix | <chemistry, molecular biology> A spiral structure in a macromolecule that contains a repeating pattern. (09 Oct 1997) |
| helix-coil transition | <molecular biology> A change in the structure of a nucleic acid or protein molecule from a highly ordered, complex structure to a random, chaotic structure. Also means that the protein or nucleic acid becomes denatured. (09 Oct 1997) |