(n.) The seed-bearing organ of a flower. It consists of an ovary, containing the ovules or rudimentary seeds, and a stigma, which is commonly raised on an elongated portion called a style. When composed of one carpel a pistil is simple; when composed of several, it is compound. See Illust. of Flower, and Ovary.
Example Sentences:
(1) Raised levels of atmospheric water cause a variety of responses in self-pollen, ranging from tube growth through the pistil to the ovary, to tubes inhibited at the stigmatic surface, accompanied by the formation of callose.
(2) When applied to sections of the pistil, these antibodies label the intercellular matrix in the stigma and transmitting tissue of the style and the cell walls in the epidermis of the placenta.
(3) We describe in this report the allelic diversity and gene structure of the S locus in Solanum tuberosum revealed by the isolation and characterization of genomic and cDNA clones encoding S-associated major pistil proteins from three alleles (S1, Sr1, S2).
(4) The label is transferred from pistil to pollen tubes apparently via the secretion products (exudate) of the pistil.
(5) The female S-locus gene products for two families showing different types of SI have been putatively identified as major pistil glycoproteins (the S-locus-specific glycoproteins of the Brassicaceae and the S-RNases of the Solanaceae).
(6) LAT52 mRNA is not detectable in pistils, sepals or non-reproductive tissues.
(7) The S-glycoproteins were expressed mainly in the upper part of the pistil and showed an increasing concentration during flower development.
(8) In situ hybridization experiments showed that at least one of these pistil-specific genes is specifically expressed in cells of the transmitting tissue.
(9) The structural events in the stigma and transmitting tissue of Petunia hybrida pistils that accompany compatible and incompatible intraspecific pollinations have been investigated in detail, together with the changes in reserve levels that also take place at this time.
(10) After pollination, the transcript levels of the pistil-specific extensin-like genes change relative to levels in unpollinated pistils.
(11) Compatible and incompatible pollen tubes growing on detached Lilium longiflorum pistils which had been prelabeled with myoinositol-U-(14)C take up a portion of the label and utilize it for biosynthesis of tube wall substance.
(12) The S2- and S3-alleles encode pistil-specific proteins of 30 kDa and 31 kDa, respectively, which were previously identified based on cosegregation with their respective alleles in genetic crosses.
(13) The maximal levels of 9612 RNA detected in anthers and vegetative organs were more than 50-fold and 250-fold lower than the level in pistils, respectively.
(14) The possible roles of the extensin-like proteins in pistils are discussed.
(15) A glycoprotein serologically related to the PR-2,N,O class is a (1,3)-beta-glucanase and is present in pistils.
(16) Here we report the characterization of a gene encoding another pistil ribonuclease of P. inflata, RNase X2.
(17) Double staining with sirofluor allows location of nuclei within pollen tubes grown in vitro, and when used after pollination enables the viewer to discriminate between nuclei within the pollen tube vs. nuclei of the pistil tissue.
(18) In the case of pistils, a pattern of labeling in ovary, style, and stigma is obtained which indicates that products of myoinositol metabolism are utilized in the biosynthesis of exudate (secretion product) of the stigma and style as well as for components of pistil cell walls.
(19) RNA gel blot hybridizations demonstrated the organ-specific expression of the extensin-like genes and their temporal regulation during pistil development.
(20) We have sought to identify pistil-specific genes that can be used as molecular markers to study pistil development.
Pollen
Definition:
(n.) Fine bran or flour.
(n.) The fecundating dustlike cells of the anthers of flowers. See Flower, and Illust. of Filament.
Example Sentences:
(1) We conclude that the priming effect is not a clinically significant phenomenon during natural pollen exposure in allergic rhinitis patients.
(2) The diagnosis of occupational allergy was based on history, skin prick tests and RAST to the pollen.
(3) Using a large clinic population with adequate controls, significant correlation between ragweed, grass or tree pollen sensitivity and the dates of birth was not obtained.
(4) For pollen asthma, six studies conclude that there were superior results with desensitization than to placebo.
(5) They were placed less than 5 m apart, and estimation of the pollen amount was made on a day-to-day basis during the pollen seasons, and on a weekly basis outside the seasons.
(6) The impact of pollen on the respiratory mucosa was modeled by studying the process by which solutes are eluted from pollen grains.
(7) One part fresh pollen grains is uniformly mixed with nine parts of the solution and left at room temperature for at least 5 hr.
(8) We have developed a reverse-type sandwich ELISA for measurement of IgG (+IgA) antibody to a major allergen of Sugi (Japanese cedar) pollens.
(9) The concentration of these pollens decrease in April, completely diminishing in May.
(10) Six atopic subjects with grass pollen allergy and six nonallergic healthy volunteers were enrolled into this study.
(11) Inhalant allergens as mite house dust, animal danders, pollens, molds and food allergens are considered, now, to be the most sensitizing agents.
(12) Most patients showed several positive skin tests to common allergens particular to grass pollen, house dust and mites (Dermatophagoides pteronyssimus).
(13) The pollen sterility (up to 30% of grains) is due to the abortive spore development.
(14) A pollen-specific cDNA clone, Zmc13, has been isolated from a cDNA library constructed to poly(A) RNA from mature maize pollen.
(15) Sixty patients with seasonal allergic rhinitis due to birch pollen were enrolled in an open, randomized parallel group study.
(16) We have studied some aspects of the atopic syndrome in this population of Southern Italy: frequency of allergic sensitization according to endogenous and extrinsic factors (particularly Parietaria officinalis, a characteristic pollen of the Southern Italian Flora), etc.
(17) It was observed that cocksfoot pollen extract is stable but there appears a slight but significant (P less than 0.05) decay in activity when the extract stored for up to 6 months was compared with a freshly prepared extract.
(18) These are collected in her pollen baskets which she takes back to the nest to feed the young after fertilising the flowers.
(19) It was observed, perhaps for the first time, that feeling worse when there is a high pollen count appears to be associated with the symptom pattern seen in winter SAD patients.
(20) In allergologic out-patient departments of Dubrovnik, Split, Sibenik, Zadar, Pula and Rijeka, 300 patients with pollinosis have been tested by the application of the prick method of group allergens of grass, tree and weed pollen, particularly of Parietariae (pellitory) pollen.