| gingival clamp | A springlike metal piece encircling or grasping the cervix of a tooth and shaped so as to retract the gingival tissue. (05 Mar 2000) |
|---|---|
| patch clamp | <physiology> A specialised and powerful variant of voltage clamping, in which a patch electrode of relatively large tip diameter (5m) is pressed tightly against the plasma membrane of a cell, forming an electrically tight, gigohm seal. The current flowing through individual ion channels can then be measured. Different variants on this technique allow different surfaces of the plasma membrane to be exposed to the bathing medium: the contact just described is a cell attached patch. If the electrode is pulled away, leaving just a small disc of plasma membrane occluding the tip of the electrode, it is called an inside out patch. If suction is applied to a cell attached patch, bursting the plasma membrane under the electrode, a whole cell patch (similar to an intracellular recording) is formed. If the electrode is withdrawn from the whole cell patch, the membrane fragments adhering to the electrode reform a seal across the tip, forming an outside out patch. (15 Mar 2000) |
| patch-clamp techniques | An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used. (15 Mar 2000) |
| Payr's clamp | A clamp used in gastrectomy or enterectomy. (05 Mar 2000) |
| glucose clamp technique | <technique> Maintenance of a constant blood glucose level by perfusion or infusion with glucose or insulin. It is used for the study of metabolic rates (e.g., in glucose, lipid, amino acid metabolism) at constant glucose concentration. (12 Dec 1998) |
| voltage clamp | <physiology, technique> A technique in electrophysiology, in which a microelectrode is inserted into a cell and current injected through the electrode so as to hold the cells membrane potential at some predefined level. The technique can be used with separate electrodes for voltage sensing and current passing, for small cells, the same electrode can be used for both. Voltage clamp is a powerful technique for the study of ion channels. See: patch clamp. (18 Nov 1997) |
| Goldblatt's clamp | A clamp applied experimentally to the renal artery to damp pulse pressure and thereby produce chronic hypertension by activation of the renin-angiotensin system. (05 Mar 2000) |
| right angle clamp | A clamp with a short 90 |
| rubber dam clamp | A springlike metal piece encircling or grasping the cervix of a tooth and so shaped as to prevent a rubber dam from coming off the tooth. (05 Mar 2000) |
| rubber dam clamp forceps | A forceps with pronged jaws designed to engage the jaws of a rubber dam clamp so that they may be separated to pass over the widest buccolingual contour of a tooth. Synonym: rubber dam clamp forceps. (05 Mar 2000) |
| rubber shod clamp | A small rubber-tipped clamp that holds sutures in place during surgery. (05 Mar 2000) |
| Mikulicz clamp | A clamp used to crush walls between proximal and distal colon in two-stage colectomy. (05 Mar 2000) |
| clamp | An instrument for compression of a structure. Compare: forceps. Origin: M.E., fr. Middle Dutch klampe (05 Mar 2000) |
| clamp connection | <microbiology> In many basidiomycete fungi a short lateral branch of a binucleate cell develops. This is the developing clamp connection. One of the nuclei migrates into it. Both nuclei then undergo simultaneous mitosis so that one end of the cell contains two daughter nuclei from each of the parental nuclei. The nucleus in the branch and the two nuclei are separated off from the centre of the cell by septa. A single nucleus remains in the central region. The clamp connection then extends towards and fuses with the central section so that a binucleate cell is reformed. (18 Nov 1997) |
| clamp forceps | A forceps with pronged jaws designed to engage the jaws of a rubber dam clamp so that they may be separated to pass over the widest buccolingual contour of a tooth. Synonym: rubber dam clamp forceps. (05 Mar 2000) |