(n.) One of the elements, a heavy, pliable, inelastic metal, having a bright, bluish color, but easily tarnished. It is both malleable and ductile, though with little tenacity, and is used for tubes, sheets, bullets, etc. Its specific gravity is 11.37. It is easily fusible, forms alloys with other metals, and is an ingredient of solder and type metal. Atomic weight, 206.4. Symbol Pb (L. Plumbum). It is chiefly obtained from the mineral galena, lead sulphide.
(n.) An article made of lead or an alloy of lead
(n.) A plummet or mass of lead, used in sounding at sea.
(n.) A thin strip of type metal, used to separate lines of type in printing.
(n.) Sheets or plates of lead used as a covering for roofs; hence, pl., a roof covered with lead sheets or terne plates.
(n.) A small cylinder of black lead or plumbago, used in pencils.
(v. t.) To cover, fill, or affect with lead; as, continuous firing leads the grooves of a rifle.
(v. t.) To place leads between the lines of; as, to lead a page; leaded matter.
(v. t.) To guide or conduct with the hand, or by means of some physical contact connection; as, a father leads a child; a jockey leads a horse with a halter; a dog leads a blind man.
(v. t.) To guide or conduct in a certain course, or to a certain place or end, by making the way known; to show the way, esp. by going with or going in advance of. Hence, figuratively: To direct; to counsel; to instruct; as, to lead a traveler; to lead a pupil.
(v. t.) To conduct or direct with authority; to have direction or charge of; as, to lead an army, an exploring party, or a search; to lead a political party.
(v. t.) To go or to be in advance of; to precede; hence, to be foremost or chief among; as, the big sloop led the fleet of yachts; the Guards led the attack; Demosthenes leads the orators of all ages.
(v. t.) To draw or direct by influence, whether good or bad; to prevail on; to induce; to entice; to allure; as, to lead one to espouse a righteous cause.
(v. t.) To guide or conduct one's self in, through, or along (a certain course); hence, to proceed in the way of; to follow the path or course of; to pass; to spend. Also, to cause (one) to proceed or follow in (a certain course).
(v. t.) To begin a game, round, or trick, with; as, to lead trumps; the double five was led.
(v. i.) To guide or conduct, as by accompanying, going before, showing, influencing, directing with authority, etc.; to have precedence or preeminence; to be first or chief; -- used in most of the senses of lead, v. t.
(v. t.) To tend or reach in a certain direction, or to a certain place; as, the path leads to the mill; gambling leads to other vices.
(n.) The act of leading or conducting; guidance; direction; as, to take the lead; to be under the lead of another.
(n.) precedence; advance position; also, the measure of precedence; as, the white horse had the lead; a lead of a boat's length, or of half a second.
(n.) The act or right of playing first in a game or round; the card suit, or piece, so played; as, your partner has the lead.
(n.) The course of a rope from end to end.
(n.) The width of port opening which is uncovered by the valve, for the admission or release of steam, at the instant when the piston is at end of its stroke.
(n.) the distance of haul, as from a cutting to an embankment.
(n.) The action of a tooth, as a tooth of a wheel, in impelling another tooth or a pallet.
Example Sentences:
(1) Thirty-two patients (10 male, 22 female; age 37-82 years) undergoing maintenance haemodialysis or haemofiltration were studied by means of Holter device capable of simultaneously analysing rhythm and ST-changes in three leads.
(2) Herpesviruses such as EBV, HSV, and human herpes virus-6 (HHV-6) have a marked tropism for cells of the immune system and therefore infection by these viruses may result in alterations of immune functions, leading at times to a state of immunosuppression.
(3) LHRH therapy leads to higher plasma LH levels and a lower FSH in response to an intravenous LHRH test.
(4) These results demonstrate that increased availability of galactose, a high-affinity substrate for the enzyme, leads to increased aldose reductase messenger RNA, which suggests a role for aldose reductase in sugar metabolism in the lens.
(5) These are typically runaway processes in which global temperature rises lead to further releases of CO², which in turn brings about more global warming.
(6) Results indicated a .85 probability that Directive Guidance would be followed by Cooperation; a .67 probability that Permissiveness would lead to Noncooperation; and a .97 likelihood that Coerciveness would lead to either Noncooperation or Resistance.
(7) It would be fascinating to see if greater local government involvement in running the NHS in places such as Manchester leads over the longer term to a noticeable difference in the financial outlook.
(8) The Frenchman’s 65th-minute goal was a fifth for United and redemptive after he conceded the penalty from which CSKA Moscow took a first-half lead.
(9) Our results indicate that increasing the delay for more than 8 days following irradiation and TCD syngeneic BMT leads to a rapid loss of the ability to achieve alloengraftment by non-TCD allogeneic bone marrow.
(10) report the complications registered, in particular: lead's displacing 6.2%, run away 0.7%, marked hyperthermya 0.0%, haemorrage 0.4%, wound dehiscence 0.3%, asectic necrosis by decubitus 5%, septic necrosis 0.3%, perforation of the heart 0.2%, pulmonary embolism 0.1%.
(11) The availability and success of changes in reproductive technology should lead to a reappraisal of the indications for hysterectomy, especially in young women.
(12) Photoirradiation of F1 in the presence of the analog leads to inactivation depending linearly on the incorporation of label.
(13) In patients with coronary artery disease, electrocardiographic signs of left atrial enlargement (LAE-negative P wave deflection greater than or equal to 1 mm2 in lead V1) are associated with increased left ventricular end diastolic pressure (LVEDP).
(14) The new Somali government has enthusiastically embraced the new deal and created a taskforce, bringing together the government, lead donors (the US, UK, EU, Norway and Denmark), the World Bank and civil society.
(15) Suggested is a carefully prepared system of cycling videocassettes, to effect the dissemination of current medical information from leading medical centers to medical and paramedical people in the "bush".
(16) Mitonafide is the lead compound of a new series of antitumor drugs, the 3-Nitronaphthalimides, which have shown antineoplastic activity in vitro as well as in vivo.
(17) The presently available data allow us to draw the following conclusions: 1) G proteins play a mediatory role in the transmission of the signal(s) generated upon receptor occupancy that leads to the observed cytoskeletal changes.
(18) In the case presented, overdistension of a jejunostomy catheter balloon led to intestinal obstruction and pressure necrosis (of the small bowel), with subsequent abscess formation leading to death from septicemia.
(19) This is rapidly followed by a gamut of changes leading to demyelination.
(20) In crosses between inverted repeats, a single intrachromatid reciprocal exchange leads to inversion of the sequence between the crossover sites and recovery of both genes involved in the event.
Plumbagin
Definition:
(n.) A crystalline substance said to be found in the root of a certain plant of the Leadwort (Plumbago) family.
Example Sentences:
(1) An excess of oxidative substrate, such as plumbagin, inactivates this enzyme, which appears to be redox-regulated.
(2) polA and recA mutants were not significantly more sensitive than wild type to killing by plumbagin.
(3) Plumbagin and shikonin induced a similar DNA cleavage pattern with topoisomerase II which was different from the cleavage patterns induced with other known topoisomerase II-active drugs.
(4) Plumbagin treatment did not induce lambda phage in a lysogen, nor did it cause an increase in beta-galactosidase production in a dinD::Mu d(lac Ap) promoter fusion strain.
(5) Aqueous leaf extracts from Dionaea muscipula contain quinones such as the naphthoquinone plumbagin that couple to different NADH-dependent diaphorases, producing superoxide and hydrogen peroxide upon autoxidation.
(6) Oxidation of lac permease with the lipophilic quinone plumbagin or alkylation with the sulfhydryl reagent N-ethylmaleimide caused a 12-fold increase in the first dissociation constant.
(7) Plumbagin and shikonin, plant metabolites which have naphthoquinone structures, induced mammalian topoisomerase II-mediated DNA cleavage in vitro.
(8) Hypochlorous acid and plumbagin, both potential sulfhydryl oxidants, induce rapid Ca2+ efflux from SR vesicles; in addition, Cu2+, which catalyzes H2O2 oxidation of cysteine, enhances H2O2-induced release.
(9) Addition of redox cycling agents such as paraquat and plumbagin at various concentrations induced up to 13 proteins in wild-type cells.
(10) Mutations in heat shock genes singly sensitized sodA sodB double mutant cells to plumbagin.
(11) P. aeruginosa showed less cyanide-insensitive respiration than E. coli upon exposure to other redox-active compounds (paraquat, streptonigrin, and plumbagin).
(12) Activity staining demonstrated that (a) anaerobically grown cells contain more extractable dehydratase activity than do aerobically grown cells; (b) exposure of E. coli to 4.2 atm O2 caused virtually complete loss of activity; (c) exposure of cells to paraquat or plumbagin in the presence of dioxygen, but not in its absence, caused a massive loss of activity.
(13) Respiration failed immediately upon the addition of growth-inhibitory levels of plumbagin.
(14) Increases of 3-fold or more were also seen with plumbagin, menadione, and phenazine methosulfate.
(15) The triphasic pattern of inotropism of plumbagin was unaffected by reserpine or propranolol treatments.
(16) Their structures were elucidated, by spectral and chemical studies, as known naphthoquinones, plumbagin, 3,3'-biplumbagin, 8-8'-biplumbagin, and triterpene, lupeol.
(17) Actively growing Escherichia coli cells exposed to plumbagin, a redox cycling quinone that increases the flux of O2- radicals in the cell, were mutagenized or killed by this treatment.
(18) Plumbagin, a compound derived from the roots of Plumbago zeylanica (Chitramool) was studied for its effect on the development of antibiotic resistance using antibiotic sensitive strains of Escherichia coli and Staphylococcus aureus.
(19) Among the selected eight compounds, menadione and plumbagin (aromatic methyl-p-quinone) induced a potent triphasic inotropic response, as reported previously for murrayaquinone-A.
(20) On the other hand, treatment with thiol group oxidants such as 5,5'-dithiobis(2-nitrobenzoic acid), plumbagin and phenazine methosulfate inhibited Gly-Sar transport.