(n.) The sum of four units; four units or objects.
(n.) A symbol representing four units, as 4 or iv.
(n.) Four things of the same kind, esp. four horses; as, a chariot and four.
Example Sentences:
(1) These included bringing in the A* grade, reducing the number of modules from six to four, and a greater attempt to assess the whole course at the end.
(2) Low birth weight, short stature, and mental retardation were common features in the four known patients with r(8).
(3) It was shown in experiments on four dogs by the conditioned method that the period of recovery of conditioned activity after one hour ether anaesthesia tested 7 to 7.5 days.
(4) However, four of ten young adult outer arm (relatively sun-exposed) and one of ten young adult inner arm (relatively sun-protected) fibroblasts lines increased their saturation density in response to retinoic acid.
(5) A 61-year-old man experienced four bouts of pancreatitis in 1 year.
(6) The promoters of the adenovirus 2 major late gene, the mouse beta-globin gene, the mouse immunoglobulin VH gene and the LTR of the human T-lymphotropic retrovirus type I were tested for their transcription activities in cell-free extracts of four cell lines; HeLa, CESS (Epstein-Barr virus-transformed human B cell line), MT-1 (HTLV-I-infected human T cell line without viral protein synthesis), and MT-2 (HTLV-I-infected human T cell line producing viral proteins).
(7) In each study, all subjects underwent four replications (over two days) of one of the six permutations of the three experimental conditions; each condition lasted 5 min.
(8) Four cytotoxic antibiotics, bikaverin, duclauxine, PSX-1 and vermiculine, were examined with respect to their interference with glycolysis and respiration and their possible ionophoric or cytolytic activity.
(9) The invaginations were classified into four easily recognized types: regular, chunky, filigree, and ridge (present only in axon hillock regions).
(10) During the study period four family outbreaks and seven recurrences of infection were observed.
(11) These four antigens consisted of S of MNSs blood group, Lua of Lutheran blood group, and K and Kpa of Kell-Cellano blood group.
(12) Binding data for both ligands to the enzyme yielded nonlinear Scatchard plots that analyze in terms of four negatively cooperative binding sites per enzyme tetramer.
(13) Even so, amputation of fifteen extremities and four other major excisions were required in twelve patients.
(14) Four of the 39 ticks in our colony were infected with a spirochete; presumably, Borrelia crocidurae.
(15) Four other independent LCMV-GP2(275-289) specific H-2Db-restricted CTL clones also expressed V alpha 4 and V beta 10 gene elements.
(16) The hospital whose A&E unit has been threatened with closure on safety grounds has admitted that four patients died after errors by staff in the emergency department and other areas.
(17) Maximal covalent binding of [4,5-14C]ronidazole to DNA also required four-electron reduction, consistent with previous studies of the covalent binding of this agent to immobilized sulfhydryl groups [Kedderis et al.
(18) We investigated whether these peptides also affect the sleep EEG in humans when given intravenously by comparing polysomnographically the effects of four boluses of (1) placebo, (2) 50 micrograms GHRH or (3) 50 micrograms SRIF administered at 22.00, 23.00, 24.00 and 1.00 h to 7 male controls.
(19) Since the start of this week, markets have been more cautious, with bond yields in Spain reaching their highest levels in four months on Tuesday amid concern about the scale of the austerity measures being imposed by the government and fears that the country might need a bailout.
(20) In 14 of the patients the imaging results were checked against the histological findings of a subsequent thymectomy, which revealed four thymomas and (with the exception of one normal thymus) hyperplastic changes in all the others.
Tetrad
Definition:
(n.) The number four; a collection of four things; a quaternion.
(n.) A tetravalent or quadrivalent atom or radical; as, carbon is a tetrad.
Example Sentences:
(1) A constellation of histologic lesions was identified in brain (diffuse meningoencephalitis with bilaterally symmetrical thalamic necrosis), liver (pericholangiohepatitis), lung (pneumonitis), and spleen (lymphoid hyperplasia); this tetrad is apparently unique to this model system.
(2) Optimal formation of complete tetrads occurred at a narrow range of pH values around 6.0.
(3) Tetrad dissection of sporulated diploids heterozygous for the wild-type and mutant allele resulted in a 2:2 segregation of mutant and wild-type phenotype indicating a single gene mutation.
(4) Increased nondisjunction is reflected by a marked increase in tetrads with two and zero viable spores.
(5) At each of these synaptic sites, L1 and L2 are invariable contributors to two of the four elements of a postsynaptic tetrad.
(6) Each glandular unit originates from an isogenic group of cells of which the four elements (tetrade) are disposed on two levels.
(7) A possibility to construct a genetic map of the yeast Pichia pinus MH4 is demonstrated on the basis of tetrad analysis.
(8) 74 of the patients showed acne conglobata, 12 acne tetrade, 11 acne fulminans, and 69 acne papulopustulosa.
(9) The mutations were assigned to specific chromosomes by chromosome loss procedures, and linkage relationships were determined subsequently by standard tetrad analysis.
(10) We used the telomeric repeat of Chlamydomonas reinhardtii, TTTTAGGG, which contains 3 guanines and has a long interguanine A + T tract, to determine whether these sequences can form intrastrand and interstrand guanine tetrads.
(11) The possibility that extragenic suppressors account for growth of clathrin-deficient cells was examined by deletion of CHC1 from haploid cell genomes by single-step gene transplacement and independently by introduction of a centromere plasmid carrying the complete CHC1 gene into diploid cells before eviction of a chromosomal CHC1 locus and subsequent tetrad analysis.
(12) The article generalizes the experience in surgical treatment of Fallot's tetrad in 20 infants.
(13) With respect to behavior, the resulting compounds appeared, presumably as a consequence of their singular generation, to contain an interstitial heterochromatic region that caused the distribution of exchanges between the elements of the compound to be abnormal (many zero and two-exchange tetrads with few, if any, single-exchange tetrads).
(14) Tetrad analysis showed the two suppressors were located about 10 map units apart, the missense suppressor being the more distal to the centromere.
(15) Defective proteinase B activity segregates 2:2 in meiotic tetrads.
(16) Fine genetic mapping was carried out by conventional tetrad analysis using the integrated LEU2 gene as a marker.
(17) Evidence for a centromeric effect on NRD was obtained, suggested by a negative correlation between the degree of NRD, c, and the distance between the region of exchange and the centromere as inferred from SET's (single exchange tetrads).
(18) Allelism tests and tetrad analysis clearly proved that the cat4 complementation group is a new class of mutant alleles affecting carbon source-dependent gene expression.
(19) In isosequential crosses, 90-95% of tetrads are 8:0.
(20) The distinguishing criteria are: lack of pigment in infected red blood cells; no circulating schizonts or gametocytes; "atypical" malarialike organisms; tetrad groups, rods, or exclamation-mark forms; and persisting parasitemia after treatment for malaria.