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111.
Canalicular adenoma is an uncommon benign tumour that generally arises in the minor salivary glands of individuals over 60 years old. This study illustrates a case of canalicular adenoma in a 70-year-old female, presenting as two distinct asymptomatic nodules in the upper lip. Immunohistochemistry analysis was performed. Clinical features, management, histology and immunoprofile from this case and from the literature are discussed. 相似文献
112.
Andrew B. Shatrov 《Zoologischer Anzeiger》2012,251(4):279-287
Anatomy and ultrastructure of prosomal salivary glands in the unfed water mite larvae Piona carnea (C.L. Koch, 1836) were examined using serial semi-thin sections and transmission electron microscopy. Three pairs of alveolar salivary glands shown are termed lateral, ventro-lateral and medial in accordance with their spatial position. These glands belong to the podocephalic system and are situated on the common salivary duct from back to forth in the above mentioned sequence. The arrangement of the medial glands is unusual because they are situated one after another on the medial (axial) body line, therefore they are termed anterior and posterior medial glands. The secretory duct of the anterior medial gland mostly turns right, and the duct of the posterior gland turns left. The salivary glands are located in the body cavity partly inside the gnathosoma and in the idiosoma in front of the brain (synganglion). Each gland is represented by a single acinus (alveolus) and is composed of several cone shaped secretory cells arranged around the large central (intra-acinar) cavity with the secretory duct base. The cells of all glands are filled with secretory vesicles of different electron density. The remaining cell volume is occupied by elements of rough endoplasmic reticulum, and the membrane enveloping vesicles may have ribosomes on its external surface. Large nuclei provided with large nucleoli occupy the basal cell zones. The pronounced development of the prosomal salivary glands indicates their important role in extra-oral digestion of water mite larvae. 相似文献
113.
Ahmed E. Hegab Vi Luan Ha Yasser S. Attiga Derek W. Nickerson Brigitte N. Gomperts 《Journal of visualized experiments : JoVE》2012,(67)
The large airways are directly in contact with the environment and therefore susceptible to injury from toxins and infectious agents that we breath in 1. The large airways therefore require an efficient repair mechanism to protect our bodies. This repair process occurs from stem cells in the airways and isolating these stem cells from the airways is important for understanding the mechanisms of repair and regeneration. It is also important for understanding abnormal repair that can lead to airway diseases 2. The goal of this method is to isolate a novel stem cell population from the mouse tracheal submucosal gland ducts and to place these cells in in vitro and in vivo model systems to identify the mechanisms of repair and regeneration of the submucosal glands 3. This production shows methods that can be used to isolate and assay the duct and basal stem cells from the large airways 3.This will allow us to study diseases of the airway, such as cystic fibrosis, asthma and chronic obstructive pulmonary disease. Currently, there are no methods for isolation of submucosal gland duct cells and there are no in vivo models to study the regeneration of submucosal glands. 相似文献
114.
Hattori M Nakamura M Komatsu S Tsuchihara K Tamura Y Hasegawa T 《Insect biochemistry and molecular biology》2012,42(1):1-9
Green rice leafhoppers (Nephotettix cincticeps) secrete watery and coagulable saliva in the feeding process. In our study, the watery salivary secretion was concentrated by ultrafiltration from “fed diet” and subjected to SDS-PAGE. The N-terminal amino acid sequence of the most predominant band at 84 kDa (designated NcSP84) was analyzed by Edman degradation. This sequence was completely consistent with the most abundant protein in the salivary gland extracts, which was separated by two-dimensional gel electrophoresis. Based on the N-terminal amino acid sequence, the complete cDNA of this protein was cloned by 5′- and 3′-RACE using degenerate primers. The deduced NcSP84 contained an open reading frame of 2061 bp encoding a putative 687 amino acids with a putative signal sequence composed of 19 amino acids. The nucleotide and amino acid sequences of NcSP84 did not share statistically significant homology with any sequences in public databases. Motif search predicted that this protein had EF-hands, the most common motif found in Ca2+ -binding proteins. As predicted, NcSP84 exhibited Ca2+-binding activity. The SDS-PAGE mobility of purified NcSP84 bound to Ca2+ tended to decline discretely, depending on the concentration of CaCl2 with which it was mixed for 1 h before adding SDS buffer. In situ hybridization and immunohistochemistry showed that the NcSP84 gene and gene product were expressed and stored in type III cells, which are the largest lobes in the primary salivary glands. The NcSP84 protein was detected in the phloem sap of rice exposed to leafhoppers, verifying that the NcSP84 protein was injected into the sieve tubes. These results suggest that NcSP84 could be secreted into the sieve tubes during feeding, which might bind Ca2+ ions that flow into sieve tubes in response to stylet puncturing. This might suppress sieve-element clogging and facilitate continuous ingestion from sieve tubes. 相似文献
115.
116.
Stephen L. Lapointe Wayne B. Hunter Rocco T. Alessandro 《Agricultural and Forest Entomology》2004,6(4):251-257
Abstract 1 External gland openings and associated structures on the elytra of teneral and mature Diaprepes root weevils, Diaprepes abbreviatus (L.), were elucidated by scanning electron microscopy (SEM). 2 There were clear differences between teneral, callow adults and fully mature adults. In the field, teneral adults remain in the pupal chamber in the soil until sclerotization of the cuticle is complete or nearly so. 3 Phenotypic variation of the elytra in this species consists of varying patterns and coloration of scaled intervals between a variable number of raised ridges devoid of scales. In addition to being thinner and lighter in colour than fully mature adults, the elytra of teneral adults were devoid of waxy hydrocarbon secretions. 4 External gland openings at the base of each scale were observed on teneral elytra and mature elytra washed with methylene chloride. 5 SEM evidence to document the production of waxy filaments by these glands and partial characterization of these by gas chromatography and mass spectrometry are presented. 相似文献
117.
Sperm number and male accessory gland compounds are often importantdeterminants of male mating success but have been little studiedin social insects. This is because mating in social insectsis often difficult to manipulate experimentally, and first evidencefor an explicit influence of accessory gland secretions on malemating success in social insects was obtained only recently.Here we perform a comparative analysis of male sexual organsacross 11 species of attine fungus-growing ants, representingboth genera with single- and multiple-queen mating. We foundthat the general morphology of the male sexual organs was verysimilar across all species, but the relative sizes of the accessoryglands and the sperm-containing accessory testes vary significantlyacross species. Small testes and large accessory glands characterizespecies with singly mated queens, whereas the opposite is foundin species with multiply mated queens. However, in the socialparasite Acromyrmex insinuator, in which queens have secondarilyreverted to single mating, males have accessory gland characteristicsreminiscent of the lower attine ants, but without having significantlyreduced their investment in sperm production. We hypothesizethat the main function of accessory gland compounds in attineants is to monopolize male paternity in similar ways as knownfrom other social insects. This would imply that the evolutionof polyandry in the terminal clade of the fungus-growing ants(the leafcutter ants) has resulted in selection for decreasedinvestment by males in accessory gland secretions and increasedinvestment in sperm number, in response to sperm competitionfor sperm storage. 相似文献
118.
Roberto Romani Nunzio Isidoro Ferdinando Bin S. Bradleigh Vinson 《Entomologia Experimentalis et Applicata》2002,105(2-3):119-128
The diapriid wasp Trichopria drosophilae Perkins (Hymenoptera: Diapriidae) attacks and develops in puparia of the common fruit fly, Drosophila melanogaster Meigen (Diptera: Drosophilidae). Host recognition of T. drosophilae was studied using both a morphological and behavioural approach. Scanning and electron microscopical observations of female parasitoid antennae showed the presence of two types of sensilla, which we named MGS1 and MGS2. The former are present on the ventral side of both the apical (A11) and sub-apical (A12) antennomeres, while the latter occur only on A12. Ultrastructural features suggest a gustatory function for these sensilla. Arena bioassays using intact or antennaectomised females and intact host puparia showed that MGS2 are necessary for achieving host acceptance. Further bioassays, where the host's anterior spiracles were covered with wax, led to a very low level of host acceptance. We suggest that the secretion produced by glands associated with the anterior spiracles act as a contact kairomone, which has to be perceived by MGS2 in order to elicit host recognition. The removal of both the female apical antennomeres (A12) led to the failure of the parasitoid to recognize its host. 相似文献
119.
Activity of salivary glands in secreting honey‐elaborating enzymes in two subspecies of honeybee (Apis mellifera L) 下载免费PDF全文
Aliaa A. Al‐Sherif Adel M. Mazeed Mohamed A. Ewis Emad A. Nafea El‐Seid E. Hagag Ahmed A. Kamel 《Physiological Entomology》2017,42(4):397-403
The activity of invertase, glucose oxidase and amylase in the cephalic (post‐cerebral) and thoracic salivary glands is determined in Egyptian and Carniolan honeybees (Apis mellifera L). For this purpose, three ages of worker bees are selected for enzyme assays. The results show that the three target enzymes are detected in the two glands during the three worker ages, except invertase, which cannot be detected in the cephalic gland of newly emerged bees of both subspecies. In both glands, the secretion of invertase is highest, followed by amylase and then glucose oxidase. In Carniolan bees, invertase secretion of the cephalic and thoracic glands increases gradually with age. In Egyptian bees, invertase increases with age only in the cephalic gland, whereas, in the thoracic gland, the highest secretion activity is detected in 10–15‐day‐old bees. The highest amounts of glucose oxidase and amylase in the cephalic gland are detected in newly emerged individuals of both Egyptian and Carniolan bees. In the thoracic gland, however, the highest activity of both enzymes is recorded only in newly emerged Egyptian bees. The results are discussed in the light of bee management and biological aspects of the two subspecies. 相似文献
120.
Akira Mizoguchi 《Physiological Entomology》2017,42(3):239-245
Many insects undergo diapause to survive adverse seasons. Although the mechanism of diapause induction is the subject of extensive study, that of diapause termination remains poorly understood. In the present study, we show the endocrine processes leading to the termination of pupal diapause in Mamestra brassicae. Diapause of this insect is terminated if the pupae are exposed to a low temperature for several weeks. During this period, the prothoracic glands (PGs) of pupae acquire the potential to secrete sufficient ecdysteroids necessary for inducing adult development. The main endocrine changes observed under the low temperature conditions are: (i) the increase in activity of the PGs in two steps; (ii) the increase in responsiveness of the glands to prothoracicotropic hormone (PTTH); and (iii) two‐step increase in PTTH gene expression in the brain. The timing of the first and second increases in PG activity roughly coincides with that of the two steps of increase in PTTH gene expression, and the timing of the increase in the responsiveness of the PGs to PTTH coincides with the second, larger increase in PTTH gene expression. The ablation of the PGs prior to cooling pupae does not affect the increase in PTTH gene expression, whereas brain removal results in a failure to increase PG activity, strongly suggesting that PTTH is the master regulator of diapause development and termination. 相似文献