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目的:明确大汗腺组织中ApoD和AR的表达水平与腋臭患者散发出气味间的关系,阐明两者在腋臭发病中的作用,为腋臭的临床治疗和干预奠定基础。方法:收集在我院整形外科就诊的腋臭病人腋下皮肤组织标本41例。手术前由3名医生共同判断患者腋下气味强度,按照能在≤1 m、≤3 m、≤5 m距离闻及气味把患者分为轻、中、重三组。随机抽取各组标本组织块进行RT-PCR检测,测定ApoD和AR在大汗腺组织中的含量。结果:根据气味强度判定标准,轻、中和重3组患者人数分别为:7人、11人和23人。按照AB 7500 Real-Time PCR系统分析结果所示ApoD相对表达量的等级与气味强度之间有线性关系(P0.05),ApoD相对表达量的等级随着气味强度的增加而升高;AR相对表达量的等级与气味强度之间有线性关系(P0.05),随着气味强度的增加而升高。结论:ApoD和AR的表达量与腋臭气味强度之间有着密切的联系。进一步证实AR可调节大汗腺组织ApoD的表达,为明确腋臭的发病机制提供了理论依据。  相似文献   
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Liacarus subterraneus is a large, soil-dwelling oribatid mite species that possesses a conspicuously shiny, clean and not wettable cuticular surface. The exocrine cuticular chemistry of this species was investigated by means of gas chromatography–mass spectrometry. Besides a fraction of hydrocarbons and a terpene, hexane extracts of whole mite bodies exhibited free carboxylic acids and their glycerides as main components. The compounds were arranged in three distinct extract profiles. Based on data from individual extracts, (1) the majority (more than 3/4) of specimens showed large amounts of 1,2-dioctanoyl-glycerol (and three other related esters) but no (or only traces of) free carboxylic acids. (2) In about 1/8 of extracts, free acids (mainly octanoic (caprylic) acid) and glycerides were detected. This second type of profile highly varied with respect to the relative abundance of acids and esters. (3) The third profile (in about 7% of specimens) exclusively exhibited free acids and no (or only traces of) glycerides. In addition, a few extracts exhibited no components at all. The extract compounds most likely originate from the lipid layer of the cerotegument of L. subterraneus. The cuticle of individuals that possessed extractable cerotegumental compounds (profile I, II, III) exhibited strong water repellent properties, while the cuticle of individuals that possessed no components in their extract did not. After hexane extraction, water repellent properties got lost. The distinct extract profiles detected most likely portray the stepwise generation of an anti-wetting, exocrine surface lipid layer of glycerides: If this layer is lost, fatty acids may be discharged again (profile III) and may subsequently esterify (profile II) to larger and more stable esters (diacyl-glycerols), eventually building up the “raincoat” (mainly profile I) of L. subterraneus.  相似文献   
186.
《Journal of morphology》2017,278(3):369-379
Clasper gland morphology and development in Potamotrygon magdalenae and its relation with the acquisition of reproductive maturity is described in males of different developmental stages (embryos, neonates, juveniles, and reproductively active and resting adults). The glands are subcutaneous masses in the proximal base of each clasper. They are partially bilobate organs with a ventral groove that bears a row of papillae. Glands tend to be asymmetric, the left gland has a larger size, a trend that has been observed in other organs of elasmobranchs. Glands are formed by radially organized tubular secretory units lined with a simple columnar epithelium with basal nuclei and granular eosinophilic cytoplasm; vascularized loose connective tissue surrounds the gland units. The gland is covered by two layers of striated muscle tissue in circular and longitudinal arrangement. The clasper glands begin to develop in neonates and their secretory activity begins in juveniles. The active secretion of the clasper gland is observed in mature males, it includes glycoproteins and sulfated mucopolysaccharides. The size of the glands has a positive and direct relationship with body size, measured as disc width. Significant differences in clasper gland size were found between mature (active and resting) and immature (neonates and juveniles) males, suggesting that the acquisition of the sexual maturity involves the increase in the size of the gland due to a highly augmented secretory activity. Therefore, clasper glands are clearly associated with the reproductive activity of males and their secretion should have an endocrine control as other sexual secondary organs. J. Morphol. 278:369–379, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
187.
Summary The dependence of cytoplasmic free [Ca] (Ca i ) on [Na] and pH was assessed in individual parietal cells of intact rabbit gastric glands by microfluorimetry of fura-2. Lowering extracellular [Na] (Na o ) to 20mm or below caused a biphasic Ca i increase which consisted of both release of intracellular Ca stores and Ca entry across the plasma membrane. The Ca increase was not blocked by antagonists of Ca-mobilizing receptors (atropine or cimetidine) and was independent of the replacement cation. Experiments in Ca-free media and in Na-depleted cells indicated that neither phase was due to reversal of Na/Ca exchange. The steep dependence of the Ca i increase on Na o suggested that the response was not due to lowering intracellular [Na] (Na i ). The effects of low Na o on Ca i were also completely independent of changes in intracellular pH (pH i ). Ca i was remarkably stable during changes of pH i of up to 2 pH units, indicating that H and Ca do not share a cytoplasmic buffer system. Such large pH excursions required determination of the pH dependence of fura-2. Because fura-2 was found to decrease its affinity for Ca as pH decreased below 6.7, corrections were applied to experiments in which large pH i changes were observed. In contrast to the relative insensitivity of Ca i to changes in pH i , decreasing extracellular pH (pH o ) to 6.0 or below was found to stimulate release of intracellular Ca stores. Increased Ca entry was not observed in this case. The ability of decreases in Na o and pH o to stimulate release of intracellular Ca stores suggest interactions between Na and H with extracellular receptors.  相似文献   
188.
Summary The dorsal and subventral esophageal glands and their secretory granules in the root-knot nematodeMeloidogyne incognita changed during parasitism of plants. The subventral esophageal glands shrank and the dorsal gland enlarged with the onset of parasitism. While secretory granules formed by both types of glands were spherical, membrane-bound, and Golgi derived, the granules differed in morphology and size between the two types of glands. Subventral gland extensions in preparasitic second-stage juveniles were packed with secretory granules which varied in diameter from 700–1,100 nm and had a finely granular matrix. Within the matrix of each subventral gland granule was an electron-transparent core that contained minute spherical vesicles. The size and position of the core varied within different granules. Few granules were present in the dorsal gland extension in preparasitic juveniles. The matrix of dorsal gland secretory granules formed during parasitism was homogeneous and more electron-dense than the matrix of subventral gland granules. Subventral gland secretory granules of parasitic juveniles and adult females appeared degenerate.  相似文献   
189.
Summary Numerous plasmodesmata occur in the walls between the secretory cells ofTamarix salt glands. The plasmalemma bounds the plasmodesmata and is continuous from cell to cell. In freeze-fracture, the e-face of the plasmalemma within the plasmodesmata is virtually devoid of intramembranous particles while, in contrast, the p-face is decidedly enriched with particles. The axial components appear to be a tightly curved membrane bilayer, as judged from measurements and their appearance in freeze-fracture, and the e-face of this membrane is also devoid of particles. Observations from both thin sections and freeze-fracture replicas indicate the presence of a circular cluster of six particles around the axial component near the cytoplasmic termini of the plasmodesmata. These particles extend from the p-face of the axial component to the p-face of the plasmalemma. These observations are summarized in a model.  相似文献   
190.
The properties of the -2-l-fucosyltransferases in submaxillary gland preparations from blood group ABH secrefors and non-secretors were compared. The level of activity in the non-secretor gland homogenates amounted to about 5% only of that found in the secretor gland preparations. The enzymes from the two sources differed in solubility properties, charge and affinities for donor and acceptor substrates. The enzyme from secretor glands showed a preference for acceptors with Type 1 [d-galactosyl(1–3)-N-acetyl-d-glucosamine] structures whereas the enzyme from non-secretor glands had a preference for Type 2 [d-galactosyl(1–4)-N-acetyl-d-glucosamine] structures.These results demonstrate that expression of the secretor gene (Se) is associated with a molecular form of the -2-l-fucosyltransferase that is different from the species present in the same tissue when theSe gene is not expressed.  相似文献   
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