follicle


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follicle

 [fol´ĭ-k'l]
a sac or pouchlike depression or cavity. adj., adj follic´ular.
atretic ovarian follicle an involuted ovarian follicle.
dental follicle the structure within the substance of the jaws enclosing a tooth before its eruption; the dental sac and its contents.
gastric f's lymphoid masses in the gastric mucosa.
graafian follicle see graafian follicle.
hair follicle one of the tubular invaginations of the epidermis enclosing the hairs, and from which the hairs grow.
Diagram of a hair follicle showing layers of hair schematically. From Copstead, 1995.
lymph follicle (lymphatic follicle)
2. lymphatic nodule (def. 2).
Naboth's f's (nabothian f's) Naboth's cysts.
ovarian follicle the ovum and its encasing cells, at any stage of its development.
primary ovarian follicle an immature ovarian follicle consisting of an immature ovum and the few specialized epithelial cells surrounding it.
primordial ovarian follicle an ovarian follicle consisting of an ovum enclosed by a single layer of cells.
sebaceous follicle a hair follicle with a relatively large sebaceous gland, producing a relatively insignificant hair.
solitary f's
1. areas of concentrated lymphatic tissue in the mucosa of the colon.
2. small lymph follicles scattered throughout the mucosa and submucosa of the small intestine. Called also solitary glands.
thyroid f's discrete cystlike units filled with a colloid substance rich in iodine; they constitute the lobules of the thyroid gland.
vesicular ovarian follicle graafian follicle.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

fol·li·cle

(fol'i-kĕl), [TA]
1. A more or less spheric mass of cells usually containing a cavity.
2. A crypt or minute cul-de-sac or lacuna, such as the depression in the skin from which the hair emerges.
Synonym(s): folliculus [TA]
[L. folliculus, a small sac, dim. of follis, a pair of bellows]
Farlex Partner Medical Dictionary © Farlex 2012

follicle

(fŏl′ĭ-kəl)
n.
1. Anatomy
a. A small bodily cavity or sac.
b. A crypt or minute cul-de-sac or lacuna, such as the depression in the skin from which the hair emerges.
c. An ovarian follicle.
d. A spherical mass of cells usually containing a cavity.
2. Botany A dry, single-chambered fruit that splits along only one seam to release its seeds, as in larkspur and milkweed.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

follicle

Anatomy
1. A sac, outpouching, cavity. See Hair follicle.
2. Lymphoid follicle. See Lollipop follicle, Target follicle Reproduction medicine Ovarian follicle A structure in the ovaries which contains a developing egg. See Graafian follicle.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

fol·li·cle

(fol'i-kĕl) [TA]
1. A more or less spheric mass of cells usually containing a cavity.
2. A crypt or minute cul-de-sac or lacuna, such as the depression in the skin from which the hair emerges.
Synonym(s): folliculus [TA] .
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

follicle

A sac-like depression or cavity, glandular or cystic in nature. Follicles may secrete new tissues as in the case of hair follicles, which synthesize and extrude hairs, and the Graafian follicles of the ovaries, which contain the eggs (ova) prior to ovulation.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

follicle

  1. any small cavity or sac (see GRAAFIAN FOLLICLE, HAIR FOLLICLE, OVARIAN FOLLICLE).
  2. a dry fruit formed by the splitting of a single carpel along a line, usually ventral, to liberate its seeds.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

Follicle

The small sac at the base of a hair shaft. The follicle lies below the skin surface.
Mentioned in: Boils
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.

follicle

1. A small gland. 2. A small cavity or deep narrow depression with excretory or secretory function. 3. A small nodule of lymphocytes and other cells occurring as a result of chronic inflammation. See papilla.
conjunctival follicle Small localized aggregation of lymphocytes, plasma and other cells appearing as white or grey elevations on the palpebral conjunctiva (tarsal area) as a result of chronic irritation (allergic, viral or mechanical such as contact lenses). See adult inclusion conjunctivitis; follicular conjunctivitis.
palpebral follicle's See meibomian glands.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann

fol·li·cle

(fol'i-kĕl) [TA]
1. A more or less spheric mass of cells usually containing a cavity.
2. A crypt or minute cul-de-sac or lacuna, such as the depression in the skin from which the hair emerges.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Background: The aim of this study was to design and assess the effects of hydroalcoholic extract of Matricaria chamomilla (MC) on preantral follicle culture of mouse ovaries in a three-dimensional culture system.
For GDF9 and BMP15, the mean staining density was determined for the cytoplasm of the granulosa cells and the oocytes of each follicle. In the evaluation, 20 instances of each type of follicle were analysed: Primordial follicles, primary follicles, secondary follicles and tertiary follicles.
In comparison to group A, group B reported the highest decline in the follicle reserve.
The researchers found that hair follicle stem cell metabolism is different from other cells of the skin.
Correlation of oocytes with ovarian reserve parameters: A moderate negative correlation of age and FSH levels were observed with quality of oocytes, number of oocyte inseminated, number of oocyte fertilized and number of follicle restored.
To make the method scalable and therefore clinically viable, a team of scientists led by Tatsuto Kageyama and Junji Fukuda from Yokohama National University proposed a new approach to regenerate hair using mouse and human hair follicle stem cells.
In the future, HairClone also plans to use cells from banked follicles to create thousands of new hair follicles from scratch, a process called 'follicle neogeneis.'
This means the fewer "immature" ones you have, the fewer "mature" follicles later in life that can release an egg cell for fertilisation.
Their study, titled "Beyond Goosebumps: Interactions between the hair follicle, the arrector pili muscle, and the sympathetic nerve during development and hair follicle regeneration," is now published as part of a (https://ascb-embo2018.ascb.org/wp-content/uploads/sites/11/2018/11/OralAbstracts2018.pdf) compilation of the presentations at the meeting. 
The results of the present study showed a remarkable relationship involving VEGF-A and melatonin in rat ovary We found that melatonin significantly protected the follicles via the angiogenic factor VEGF-A, which is closely related to the angiogenesis process in the follicle.
Only 0.01% of the dissected females possessed an ovary with 3 ovarioles; when this occurred the ovary was not fully developed and possessed no mature follicles. Follicle oocytes were surrounded by a layer of follicular cells that constituted the follicular epithelium (Fig.