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51.
Mammary gland adenomyoepitheliomas are benign complex mammary gland tumors composed of neoplastic cells of epithelial and myoepithelial origins, described in many species (humans, dogs, cats, rats) and rarely in mice. We report here an adenomyoepithelioma in a C57BL/6 female mouse. Histologically, tubes and cords formed by neoplastic epithelial cells were separated by bundles of neoplastic myoepithelial cells in a clear and partially mucinous matrix. The tumor displayed characteristics of a benign neoplastic proliferation with a compressive growth pattern, and moderate cellular pleomorphism and mitotic index. At immunohistochemistry, the epithelial cells were strongly cytokeratin positive; the myoepithelial cells were weakly cytokeratin positive and strongly smooth muscle actin positive. This is to our knowledge, the first report of a mammary gland adenomyoepithelioma in a C57BL/6 mouse.  相似文献   
52.
Fms-like tyrosine kinase 1 (Flt-1) performs a subordinate effector role in mesenchymal angiogenesis and potentially serves an equally important functional role as a self-contained receptor in epithelial cells. In both endothelial cells and epithelial cells, Flt-1/vascular endothelial growth factor receptor 1 (VEGFR1) downstream signalling is involved in regulating cellular processes such as cytoskeletal changes and cellular survival protection. Cellular renewal of the gastrointestinal mucosa is based on these processes and might involve Flt-1/VEGFR1 pathway activities; the molecular mechanisms regulating these cellular dynamics remain unclear. This study was performed to investigate the presence and distribution of Flt-1/VEGFR1 in epithelial cells of the gastrointestinal tract by immunohistochemistry (IHC). Gastrointestinal tissues were taken from eight anatomical sites from mouse, rat, dog, swine and monkey. Present results revealed a cytosolic Flt-1/VEGFR1 staining pattern in mucosal epithelial cells for all investigated species. Non-epithelial structures also displayed a distinct Flt-1/VEGFR1 positivity and included vascular smooth muscle walls, enteric smooth muscle layers, the enteric nervous system and capillary endothelial cells. Diverse intensities of the Flt-1/VEGFR1 binding reaction within each species were observed in the intestinal mucosa with a strong immunoreaction in enterocytes and with a low protein expression in the ileum in most species. Crypt cells in the large intestine were mostly negative for Flt-1/VEGFR1. A peculiar and mainly intranuclear antibody binding reaction was found in Brunner's gland epithelial cells of mouse and rat whereas Brunner's glands of dog, swine and monkey remained completely negative. These results indicate a potential involvement of Flt-1/VEGFR1 in normal restitution of gastrointestinal structures in the species studied. Additionally, intranuclear Flt-1/VEGFR1 antibody binding in Brunner's glands of rodents may suggest a nuclear translocation of the transmembrane VEGFR1 which has not previously been described.  相似文献   
53.
54.
Neuronal origins, peptide phenotypes and target distributions were determined for sensory and autonomic nerves projecting to the eyelid. The retrograde tracer, Fluoro-Ruby, was injected into the superior tarsal muscle and meibomian gland of Sprague-Dawley rats. Labelled neurons were observed within the pterygopalatine (31 ± 6 of a total of 8238 ± 1610 ganglion neurons), trigeminal (173 ± 43 of 62 082 ± 5869) and superior cervical ganglia (184 ± 35 of 21 900 ± 1741). Immunostaining revealed vasoactive intestinal polypeptide immunoreactivity (VIP-ir) in nearly all Fluoro-Ruby-labelled pterygopalatine ganglion neurons (86 ± 5%) but only rarely in trigeminal (0.3 ± 0.3%) or superior cervical (1.4 ± 1.4%) ganglion neurons. Calcitonin gene-related peptide (CGRP)-ir was not observed in pterygopalatine or superior cervical ganglion somata, but was present in 24 ± 4% of trigeminal neurons. Bright dopamine β-hydroxylase (DBH) immunofluorescence was observed in the majority of eyelid-projecting neurons within the superior cervical ganglia (65 ± 5%) and lighter staining was detected in pterygopalatine neurons (63 ± 3%), but no DBH-ir was observed in trigeminal neurons. Examination of eyelid sections revealed dense VIP-ir innervation of meibomian gland acini and vasculature and modest distribution within tarsal muscle. CGRP-ir fibers surrounded ductal and vascular elements of the meibomian gland and the perimeter of tarsal muscle. DBH-ir fibers were associated with meibomian gland blood vessels and acini, and were more densely distributed within tarsal muscle. This study provides evidence for prominent meibomian gland innervation by parasympathetic pterygopalatine ganglion VIP-ir neurons, with more restricted innervation by sensory trigeminal CGRP-ir and sympathetic neurons. Tarsal muscle receives abundant sympathetic innervation, as well as moderate parasympathetic and sensory CGRP-ir projections. The eyelid contains substantial non-CGRP-ir sensory innervation, the targets of which remain undetermined. The distribution of identified autonomic and sensory fibers is consistent with the idea that meibomian gland function, as well as that of the tarsal muscle, is regulated by peripheral innervation.  相似文献   
55.
Malignant salivary gland tumors in children are very rare. This report describes the autopsy of a child with parotid gland cancer. The patient, a 10 month old girl, was admitted to the Nagoya First Red Cross Hospital with facial nerve palsy. lncisional biopsy of a post-auricular tumor was performed, and undifferentiated carcinoma was diagnosed. The patient died 6 months later of respiratory failure due to pulmonary lymphangitis carcinomatosis. Light and electron microscopic and immunohistochemical examinations of the tumor tissue were performed. The tumor cells were arranged in a medullary, sheet-like manner. Keratinization or mucus lakes were not observed. PAS-alcian blue staining demonstrated intracytoplasmic mucus as granules, and also small intercellular droplets of mucus that might otherwise have been unnoticed. Ultrastructurally, some of the tumor cells had tonofilament-like keratin filaments, and also small hollow spaces bounded by microvilli and containing secretory particles. These were stained by antisera against CEA and keratin. These findings are suggestive of differentiation to mucoepider-moid carcinoma. We also review and discuss malignant salivary tumors of epithelial origin in children. Acta Pathol Jpn 40: 149–152, 1990.  相似文献   
56.
The Association of Directors of Anatomic and Surgical Pathology has developed recommendations for the surgical pathology report for common malignant tumors. The recommendations for tumors of the adrenal cortex and medulla are reported herein. Received: 30 March 1999 / Accepted: 30 March 1999  相似文献   
57.
D-Aldosterone (5 ng/microliter/h) was infused for 6 days into the region of the subcommissural organ (SCO) of conscious, adult male Sprague-Dawley rats. Aldosterone increased urinary sodium loss and the sodium/potassium ratio. Although probably central in origin, these effects still occurred when cannulae were displaced up to 1 mm from the targeted SCO placement. Aldosterone decreased adrenal medullary cross-sectional area without affecting cell density. This effect was highly dependent on proper cannula placement and was not observed when the cannula tip was not in contact with the cerebrospinal fluid of the pineal recess over the rostral two-thirds of the SCO. We conclude that aldosterone increases sodium excretion by an action in the SCO and/or adjacent structures. We also postulate a negative trophic relationship between mineralocorticoids and the adrenal medulla mediated by the SCO.  相似文献   
58.
为了解先天性肾上腺皮质增生症患者的21-羟化酶CYP21B基因中Ile~(172)→Asn错义突变的发生率,根据放大受阻突变体系(Amplificationrefractorymutationsystem,ARMS)的要求,设计了3种引物:5'd(TTGGGAGACTACTCCCTGCTCT)3'(共同引物)、5'd(AGGTGAGGTAACAGA)3'(正常引物)、5'd(AGGTGAGGTAACAGT)3'(突变引物),在7例患儿中进行了检测,发现具有本突变者3例。对其中一例进行的家系分析,结果提示:这组引物有快速、简便的优点,不需使用同位素就能对具有Ile~(172)→Asn变异的高危家庭成员作产前诊断。  相似文献   
59.
采用墨汁硝酸银水溶液局部动脉灌注方法,研究了胎儿、犬和家兔肾上腺(总计80例)器官内的淋巴管.所见结果表明:胎儿和犬肾上腺被膜内及腺体内的较粗大静脉周围存在淋巴管和毛细淋巴管;家兔肾上腺的淋巴管仅分布于被膜内;在肾上腺皮质和髓质的实质内,无论胎儿、犬和兔,仅有血管并无淋巴管或毛细淋巴管.  相似文献   
60.
A dialysis tubing was implanted in the adrenal gland of rats. Adrenomedullary secretion products were dialysed into Ringer solution in the awake animal. Catecholamines (CAs) and methionine-enkephalin (Met-Enk) were measurable under resting conditions. Epinephrine, norepinephrine and Met-Enk-like immunoreactive material increased following application of an immobilization stress for 5 min. The results demonstrate that adrenomedullary CAs and peptides are coreleased. They also demonstrate that Met-Enk-like immunoreactive material is released under stress.  相似文献   
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