(1) In anther sections hybridized with [3H]histone probe, gene expression was only detected in the endothecium of the premeiotic anther and in the bicellular pollen grains.
(2) Poly(A)+RNA concentration decreased in these cell types during meiosis and attained very low levels in the disintegrating tapetum and the persistent endothecium of the post-meiotic anther.
(3) Preparatory to meiosis, there was a sharp decrease in poly(A)+RNA concentration in the epidermis and middle layer of the anther wall, although the label persisted in the endothecium, tapetum and microsporocytes.
Endothelium
Definition:
(n.) The thin epithelium lining the blood vessels, lymphatics, and serous cavities. See Epithelium.
Example Sentences:
(1) Electronmicroscopical investigations have revealed that, under normal conditions, a minor vesicular transfer of intravenously injected peroxidase occurs across the endothelium in segments of arterioles, capillaries and venules, especially in arterioles with a diameter about 15-30 mu.
(2) The vascular endothelium is capable of regulating tissue perfusion by the release of endothelium-derived relaxing factor to modulate vasomotor tone of the resistance vasculature.
(3) Selective removal of endothelium had no effect on BK-induced contraction or the action of the antagonists.
(4) Combined SEM and TEM examination of the endothelium of compressed segments revealed "craters" and "balloons", blebs and vacuoles, swollen mitochondria, dilated granular endoplasmic reticulum, and subendothelial edema.
(5) DNA synthesis by endothelium subsequently increased and within 48 hr new blood vessel formation was detected.
(6) Endothelium-dependent relaxations to acetylcholine and endothelium-independent relaxations to nitric oxide were observed in rings from both strains during contraction with endothelin.
(7) Rings of isolated coronary and femoral arteries (without endothelium) were suspended for isometric tension recording in organ chambers filled with modified Krebs-Ringer bicarbonate solution.
(8) The observations support the idea that the function of pericytes in the choriocapillaris, the major source of nutrition for the retinal photoreceptors, resides in their contractility, and that pericytes do not remove necrotic endothelium during capillary atrophy.
(9) The relaxations in response to a nonreceptor-mediated endothelium-dependent vasodilator, A23187, and an endothelium-independent vasodilator, sodium nitroprusside, were not different between normal and diabetic aortas.
(10) Nitric oxide (NO) is a major component of endothelium-derived relaxing factor (EDRF) the synthesis of which from L-arginine can be inhibited by NG-monomethyl-L-arginine (L-NMMA).
(11) Endothelin-1 (ET-1) is a novel vasoconstricting and cardiotonic peptide that is synthesized by the vascular endothelium.
(12) Hydrostatic occlusion of arteries with 12 kPa (90 mmHg) for 30 sec did not affect endothelial morphology and fibrinolytic activity, but after occlusion for 5 or 20 min the endothelium in both arteries and veins was severely damaged.
(13) From these results, it is concluded that (1) isolated rat common carotid arteries have both H1- and H2-receptors, (2) there are few vasoconstrictory H1-receptors, (3) both H1- and H2-receptors mediate only vasodilation but not vasoconstriction, and (4) EDRF from the endothelium might participate in histamine-induced vasodilation via not only H1- but also H2-receptors.
(14) Endothelium is indisputably a highly specialized tissue which mediates and controls many physiological and pathological processes.
(15) The endothelium of bone marrow sinuses is a continuous layer which is selective in its cellular transport.
(16) Compared to normal aorta there was a highly significant increase in proteoglycan in lipid-containing lesions, which was also associated with the presence of regenerated endothelium.
(17) The involvement of the endothelium and the role of change in membrane potential are evaluated and lead to the conclusion that pressure and flow effects do not depend exclusively on the release of endothelial factors nor the activation of voltage-gated Ca2+ channels.
(18) Vasodilation was not altered significantly by removal of endothelium or by pretreatment with propranolol or indometacin.
(19) Vascular stretch increases the activity of arterial baroreceptors along with the production and release of substances from the endothelium.
(20) Intravenous carbon black or thioflavin S (a fluorescent vital stain for endothelium) were used to demonstrate the distribution of coronary arterial flow in control and damaged myocardium.