(n.) A resinous substance produced mainly on the banyan tree, but to some extent on other trees, by the Coccus lacca, a scale-shaped insect, the female of which fixes herself on the bark, and exudes from the margin of her body this resinous substance.
Example Sentences:
(1) Fifty-six percent of Lac+ transconjugants were resistant to the S. cremoris M12R lytic phage.
(2) We have previously shown that about 90% of total Escherichia coli lac repressor synthesized in mammalian cells is located in the cytoplasm [Hu and Davidson, Cell 48 (1987) 555-566].
(3) Hfr strains B4 and B8 transfer the Escherichia coli chromosome in opposite directions, each transferring lac(+) as the last known marker.
(4) Combined with histological analysis, these results suggest a more rapid recovery of normal spermatogenesis after physical insult with LAC treatment.
(5) The F'lac+ episome of Escherichia coli origin was transferred by conjugation with frequencies of 10(-7) to 10(-5) from Erwinia amylovora to 14 out of 15 Salmonella typhimurium trp female parents.
(6) A protein identical in properties to FIII L. casei lac was isolated from clones of E. coli carrying this DNA insert.
(7) Only one monoclonal antibody strongly inhibited cAMP binding by CRP, and this was accompanied by a consequent strong inhibition of both lac DNA binding and abortive initiation by RNA polymerase.
(8) These ends were cloned separately in lambdapMu hybrid particles that derived from a single Mu lysogen in the lac Z part of lambdaplac5.
(9) The structure of F13, a plasmid containing lac, purE, and proC, has been determined by heteroduplex analysis.
(10) In this case, resistance markers were lost when the transductants became Lac- but the derivatives remained copper resistant.
(11) Circular dichroic studies and hydropathy profiling of the amino-acid sequence of this 'lac' permease suggest a secondary structure in which the polypeptide consists of 12 hydrophobic segments in alpha-helical conformation that traverse the membrane in zig-zag fashion connected by shorter, hydrophilic domains with most of the charged residues and many of the residues commonly found in beta-turns.
(12) The strength of the STII gene promoter was compared with that of the ompF and lac operons, which were similarly fused to the lacZ gene.
(13) From the results of potassium iodide quenching of fluorescence from the tryptophans, and from attempts to react the native lac repressor with dimethyl(2-hydroxy-5-nitrobenzyl) sulfonium bromide and 2-hydroxy-5-nitrobenzyl bromide, we propose that tryptophan residue 209 is involved in a conformational change of the protein upon binding of inducer, but does not come in direct contact with inducer.
(14) In cells growing with interdivision times of 27, 36, and 55 min, the F'lac replicated at various stages in the division cycle but always at approximately the same time as initiation of chromosome replication.
(15) Expression of the blood group carbohydrates was similar in follicular and radicular cysts but differed from that seen in odontogenic keratocysts by the failure to detect N-lac in the latter.
(16) The phage lambda operator OR1 and a 18 base pair symmetric lac operator have been studied by high resolution NMR.
(17) Deletions covering all or part of the transfer region, as well as of lac and of pif, were obtained in the course of this analysis.
(18) A Mud(Ap, lac) prophage has been shown to be inserted into the ptsH gene of E. coli.
(19) From transient expression studies of the fusion gene between the chloramphenicol acetyltransferase and lac genes, it was found that the lacCAP binding site could act as an enhancer activity on the SV40 promoter, and also as an additive enhancer activity to the SV40 enhancer in HeLa cells.
(20) Expression of chlD-lac was increased in cells grown with nitrate.
Tac
Definition:
(n.) A kind of customary payment by a tenant; -- a word used in old records.
Example Sentences:
(1) In 6 cases of T cell lymphoma, 5 cases were positive for T3+ and Tac+ each; 4 for T11+ and 2 for T6+ while all were positive for T4 and negative or weakly positive for T8A.
(2) The tetracaine component of TAC is superfluous for obtaining topical anesthesia of minor dermal lacerations of the face in children.
(3) The response of Tac rosette positive cells to recombinant IL-2 was always higher than that of the Tac rosette negative or unselected cells, indicating that this rosette method specifically selects T cells expressing IL-2 receptor.
(4) The role of interleukin 2 (IL-2) in the activation of suppressor T cells was investigated by using the monoclonal antibody anti-Tac, which blocks the binding of IL-2 to the 55-kDa peptide of the high-affinity IL-2 receptor.
(5) The IL 2 receptor on T4+ T-CLL cells was indistinguishable from that on normal activated T cells with respect to molecular weight and downregulation by the anti-Tac antibody.
(6) The capacity for T cell proliferation and the expression of Tac antigen (IL-2 receptor) was assessed during the post-burn period in patients with injuries ranging from 5-68% total body surface area.
(7) Comparison with the respective wild-type nucleotide sequence shows only one nucleotide change, G----A, causing a replacement of cysteine-58 (TGC) with tyrosine (TAC) in the E3 protein of ts1.
(8) A procedure is described for the phagocytic labeling of white blood cells (WBC) with high specific activity 99mTc--albumin colloid (TAC).
(9) Both the neuA and neuC genes are coexpressed under the control of a single upstream T7 or tac promoter, suggesting that neuA and neuC are part of an operon.
(10) The addition of anti-Tac during a preculture period inhibited the generation of Epstein-Barr virus (EBV)-induced suppressor T cells and of suppressor T cells induced in an antigen-specific system by a high antigen (sheep red blood cell) concentration.
(11) In contrast to wild-type IL-2R alpha, shedding of mutant Tac protein is strongly reduced.
(12) The complete transcriptional unit, incorporating the tac promoter and rrnB transcription terminators flanking the Pf1 coat protein gene, was excised from the expression plasmid and cloned into the intergenic space of bacteriophage R252, an fd bacteriophage that carries an amber mutation in its own major coat protein gene.
(13) The time course of expression of other known activation antigens, such as Tac and transferrin receptor, was comparable to that of CK226.
(14) In previous work, our laboratory has molecularly cloned the cDNA coding for the bovine IL-2 and IL-2R (p55, Tac) proteins.
(15) The degree of inhibition of protein synthesis, however, was not closely correlated with expression of CD25 antigen (low-affinity Mr 55,000 glycoprotein, IL-2R, Tac antigen) on ATL cells.
(16) Unlike other reported cases of Thp-CLL, fresh leukemic cells from this patient were positive with the anti-Tac monoclonal antibody, which recognizes the receptor for interleukin-2 (IL-2).
(17) SF CD4+ cells from RA and non-RA arthritides expressed the Tac antigen much more frequently than corresponding CD8+ cells (54 and 58% versus 16 and 17%).
(18) A Tn5tac1 insertion just inside the 3' end of cysQ, with its isopropyl-beta-D-thiogalactopyranoside-inducible tac promoter pointed toward the cysQ promoter, resulted in auxotrophy only when isopropyl-beta-D-thiogalactopyranoside was present; this conditional phenotype was ascribed to collision between converging RNA polymerases or interaction between complementary antisense and cysQ mRNAs.
(19) In addition, a monoclonal antibody (moAb) against the IL2 receptor (IL2-R; anti-Tac) inhibited the spontaneous colony formation from T-CFC of both groups of patients.
(20) The artificial secretory molecule of the IL-2 receptor named "bottom-less" receptor was able to react with anti-Tac antibody and to bind IL-2.