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81.
Abbas Agaimy Robert Stoehr Lars Tgel Arndt Hartmann Thomas Cramer 《Head and neck pathology》2021,15(1):361
Porocarcinoma (synonym: malignant eccrine poroma) is a rare aggressive carcinoma type with terminal sweat gland duct differentiation. The squamous variant of porocarcinoma is even less frequent and might be indistinguishable from conventional squamous cell carcinoma (SCC). We herein describe the first case of a carcinoma presenting as a primary parotid gland malignancy in a 24-year-old male without any other primary tumor. Total parotidectomy and neck dissection were performed followed by adjuvant chemoradiation. The patient remained alive and well 10 months after diagnosis. Histology showed keratinizing SCC infiltrating extensively the parotid gland with subtle poroid cell features. Oncogenic HPV infection was excluded by DNA-based testing. NGS analysis using the TruSight RNA fusion panel (Illumina) revealed a novel YAP1-MAML2 gene fusion. This gene fusion was reported recently in a subset of cutaneous porocarcinoma and poroma. This case of poroid SCC (or squamoid porocarcinoma) adds to the differential diagnosis of SCC presenting as parotid gland tumor and highlights the value of molecular testing in cases with unusual presentation.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01181-9) contains supplementary material, which is available to authorized users. 相似文献
82.
肾上腺髓质微血管构筑 总被引:2,自引:0,他引:2
本文以树脂铸型扫描电镜法,观察大鼠和小鼠肾上腺髓质的微血管构筑,并特别注意髓质血管和皮质血管的相互关系;此外切片观察测量了肾上腺髓质两种嗜铬细胞的分布。肾上腺皮质集合小静脉发出侧支,分布于髓质,构成了门静脉循环特点。小鼠的肾上腺髓质,主要由这种侧支供应;而大鼠的髓质,还有多支髓质动脉供应。从血管铸型上表现出的明显局部环形缩窄推测,肾上腺髓质血液循环有若干括约装置控制。大、小鼠两种嗜铬细胞在肾上腺髓质内的分布不同,大鼠的呈随机分布;小鼠的 NA 细胞多靠近皮质,而 A 细胞多远离皮质。 相似文献
83.
84.
为进一步了解干燥综合征的病因,作者用ELISA法检测了干燥综合征患者的泪腺和血中的白介素2(IL-2),白介素2受体(IL-2R),白介素6(IL-6),白介素6受体(IL-6R),并与正常人相比较.结果:干燥综合征患者泪腺中的IL-2,IL-2R,IL-6R的含量比正常人明显升高,其血中的IL-2,IL-2R有改变.以上显示,干燥综合征患者泪腺中的白介素升高及血中的白介素的改变与该病的免疫性炎症反应有关. 相似文献
85.
12例儿茶酚胺症均经病理及手术证实,其中10例为肾上腺嗜铬细胞瘤(AMP),1例肾上腺髓质增生(AMH),1例恶性嗜铬细胞瘤。CA和VMA测定对诊断有特异性,AMH的诊断依赖于病理,对于无高血压症状的嗜铬细胞瘤,认为采用“静止嗜铬细胞瘤”为妥,手术是治疗儿茶酚胺症的根本治疗方法,充分的术前准备是重要的。 相似文献
86.
Tomoaki Yuhi Akihiko Wada Ryuichi Yamamoto Masanobu Urabe Hiromi Niina Futoshi Izumi Toshihiko Yanagital 《Naunyn-Schmiedeberg's archives of pharmacology》1994,350(2):209-212
We have previously reported that in bovine adrenal chromaffin cells Ptychodiscus brevis toxin-3 (PbTx-3) does not alter the veratridine-induced 22Na influx when given alone, but increases the influx of 22Na when co-applied with either - or -scorpion venom (Wada et al. 1992). In the present study, we characterized [3H]PbTx-3 binding in bovine adrenal chromaffin cells. [3H]PbTx-3 binding was saturable, reversible and of high-affinity with an equilibrium dissociation constant (Kd) of 32.0±4.9 nmol/1 and a maximum binding capacity Bmax of 6.2 ± 1.2 pmol/4 × 106 cells (4.5 ± 0.9 pmol/mg cell protein). A Hill plot revealed the lack of cooperative interaction among the binding sites. Unlabelled PbTx-3 inhibited [3H]PbTx-3 binding with an IC50 of 31 nmol/l. However, tetrodotoxin, veratridine, - and -scorpion venom, or veratridine in combination with either - or -scorpion venom did not alter [3H]PbTx-3 binding. All these results suggest that PbTx-3 binds to a site (site 5) distinct from the previously known four toxin binding sites, which does not gate voltage-dependent Na channels by itself, but is specifically involved in the allosteric modulation of Na channels in adrenal medullary cells.
Correspondence to: A. Wada at the above address 相似文献
87.
此专家系统在修善顾博士行医经验和治疗原则的基础上 ,利用多媒体技术 ,结合声频、视频、图片和文本以治疗乳腺增生病。在医疗设计中 ,着重于顾博士的类型识别要点和乳腺增生病的自然规律。尤其 ,此医疗设计阐明了顾博士所总结的有价值的治疗经验 ,以突出此专家系统的科学性、实用性和可操作性。笔者曾将此专家系统应用于临床 1 30份病例的治疗中。其结果表明此专家系统的临床治疗正确率与顾博士临床治疗相对照达 98%。 相似文献
88.
Definition and pathology of primary sclerosing cholangitis 总被引:4,自引:1,他引:3
Nakanuma Y Harada K Katayanagi K Tsuneyama K Sasaki M 《Journal of Hepato-Biliary-Pancreatic Surgery》1999,6(4):333-342
Although primary sclerosing cholangitis (PSC) is not a common disease, it is important in the differential diagnosis of hepatobiliary
tract diseases in clinical practice. A diagnosis of PSC should be made only after the exclusion of similar diseases with well
known etiologies or pathogeneses. In this review, the pathology of classical PSC and its variants or related diseases is highlighted.
PSC is histologically characterized by progressive periductal fibrosis with luminal stenosis or obliteration, along with the
formation of a fibrous core, as well as dilatation (cholangiectasis). Its etiology is unknown. Bacterial ascending cholangitis
is superimposed on its long clinical course. Such a heterogeneous distribution of biliary lesions with biliary obliteration
and cholangiectasis is responsible for the radiological demonstration of biliary abnormalities, particularly the beaded appearance.
Sampling variability is common in needle or wedge biopsied specimens. As a result of biliary damage, the liver shows progressive
cholestatic change followed by biliary fibrosis and cirrhosis, and this hepatic progression is divisible into four stages.
There are several variants of PSC or related diseases, such as localized biliary sclerosis and stenosis, sclerosing cholangitis
associated with inflammatory pseudotumor, and PSC-autoimmune hepatitis overlapping syndrome. Cholelithiasis, including secondary
hepatolithiasis and, to a lesser degree, biliary carcinoma and dysplasia, are also known to develop at the perihilar bile
ducts as a late complication of PSC.
Received for publication on March 8, 1999; accepted on April 30, 1999 相似文献
89.
K. Kajiwara N. Yanagihara T. Ioka M. Tsutsui A. Yashiro Y. Toyohira Y. Nakashima F. Izumi 《Naunyn-Schmiedeberg's archives of pharmacology》1999,360(1):99-102
Low density lipoprotein (LDL) and lipoprotein(a) suppress catecholamine secretion in cultured adrenal medullary cells. Modification
of LDL by oxidation or acetylation potentiates various atherogenic actions of LDL. In the present study, we investigated whether
the modification of LDL influences catecholamine secretion in cultured bovine adrenal medullary cells. The exposure of LDL
to CuSO4 caused a time-dependent oxidation of LDL. Maximal oxidation of LDL was observed after exposure to CuSO4 for 24 h. Native LDL inhibited catecholamine secretion induced by carbachol to 68.5% of control. Oxidized LDL caused further
inhibition of carbachol-evoked secretion to 37.6% of control. Acetylated LDL inhibited it to 41.0% of control. There was a
good correlation between the extent of LDL oxidation and the inhibition of catecholamine secretion. These results suggest
that oxidation or acetylation of LDL augments its inhibitory effect on the secretion of catecholamines. Since catecholamines
are a risk factor of atherosclerosis, the inhibitory effect by such modified LDL may be a mechanism inhibiting atherosclerotic
progression.
Received: 29 January 1999 / Accepted: 19 April 1999 / Published online: 22 June 1999 相似文献
90.
B. P. Hauffa J. Sólyom E. Gláz C. H. L. Shackleton G. Wambach P. Vecsei H. Stolecke J. Homoki 《European journal of pediatrics》1991,150(3):149-153
Infection-triggered, life-threatening salt-loss and hyperkalaemia developed in two male infants with wasting, inappropriately low plasma aldosterone concentrations and elevated plasma renin activity. The presumptive diagnosis of a defective terminal step in aldosterone biosynthesis was made by the presence of large amounts of 11-dehydrotetrahydrocorticosterone and its 18-hydroxylated metabolite (18-OH-THA), free 18-hydroxycorticosterone (18-OH-B) and 18-hydroxytetra-hydrocorticosterone in the urine of both patients. The diagnosis of corticosterone methyl oxidase type II (CMO II) deficiency was confirmed by an elevated urinary 18-OH-THA to tetrahydroaldosterone ratio in one boy and by an elevated plasma 18-OH-B to aldosterone ratio in the other boy. Unknown steroids responsible for the salt-loss were not identified. Sodium supplementation but not short-term high dose oral 9-fluorcortisol (FF) normalized the hyponatraemia in one patient, in whom sodium (Na+)/potassium (K+) co-transport was decreased. Both patients eventually received long-term FF treatment to prevent impairment of longitudinal growth caused by chronic salt-loss. The diagnosis of CMO II deficiency should always be confirmed by elevated precursor-product ratios in urine or plasma, using radioimmunoassays with prior chromatographic separation. Metabolic studies as the short-term response of serum Na+ to high dose FF may not be helpful in differentiating aldosterone biosynthetic defects from endorgan resistance to mineralocorticoids.Dedicated to Professor Dr. Walter Teller, on the occasion of his 60th birthdayPresented in part at the 27th Annual Meeting of the European Society for Paediatric Endocrinology, Copenhagen, Denmark, June 1988 相似文献