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41.
Hiroshi Takahashi Nobuo Tsuda Shuichi Fujita Fumiaki Tezuka Haruo Okabe 《Pathology international》1990,40(9):655-664
Fifty-four adenoid cystic carcinomas (ACC) arising in major and minor salivary glands as well as in normal salivary glands were studied by immunohistochemistry for the presence of vimentin, neuron specific enolase (NSE), α1 -antichymotrypsin (α1 -ACT) and α1 -- antitrypsin (α1 -- AT). Five patterns of histological differentiation were found in ACC, and for the cellular components of each, it was possible to establish a special immunohistochemical profile. In ACC, vimentin-positive cells were observed in the outer tubular, cyst-lining and small angular cells. NSE was positive in the myoepithelial cells of normal salivary gland. Neoplastic cells of ACC showed NSE positivity mainly in the small angular cells and partly in the duct luminal cells. α1 -ACT was localized in the intercalated duct cells and serous acinar cells of normal salivary gland, and in the duct luminal cells of ACC. α1 -AT could not be detected in any of the epithelial cells of normal salivary gland. In ACC, eosinophilic hyaline material in the cribriform spaces was positive for α1 -AT, but no positivity was demonstrated in tumor cells. The present study showed that there are at least two populations of tumor cells in ACC: duct luminal cells that express α1 -ACT, thus indicating their ductal character, and small angular cells that express vimentin, characteristic of non-luminal cells. Moreover, our results indicate that α1 -AT is a useful marker of basement membrane-like material. 相似文献
42.
Ole Holger Petersen 《Pflügers Archiv : European journal of physiology》1971,323(2):91-95
Summary The cat submandibular gland was perfused with a normal NaCl Locke solution and a chloride-free sucrose solution. The numerical increase in acinar membrane potential (secretory potential) was recorded after intra-arterial injection of acetylcholine.There was no significant difference between the size of the secretory potentials recorded during perfusion with the sucrose solution [23.6 mV±1.4 (n=23)] and the size of those recorded during the control periods [20.6 mV±1.2 (n=24)].The maximal value of the membrane potential after injection of acetylcholine was higher [51.8 mV±2.4 (n=23)] during perfusion with the sucrose solution than during the control periods [44.8 mV±1.8 (n=22)].The results show that a pump transporting chloride into the acinar cells cannot be responsible for the generation of the secretory potentials. The results are best accounted for by assuming that an outward passive transport of potassium, being partly short-circuited by an inward passive sodium transport, is responsible for the change in membrane potential after stimulation with acetylcholine.Supported by the Danish State Research Foundation and Johann and Hanne Weimann's legate. 相似文献
43.
Michal M Skálová A Mukensnabl P 《Virchows Archiv : an international journal of pathology》2000,437(4):465-468
We describe a 45-year-old man who had a 2-year history of a slowly enlarging tumor in the left parotid gland. Histologically,
the tumor was a mucinous cystadenoma with focal apocrine differentiation, which revealed a widespread invasive micropapillary
adenocarcinoma component. A rim of lymphoid tissue surrounded the margins of the micropapillary carcinoma. The invasive micropapillary
adenocarcinoma component was morphologically identical with the invasive micropapillary carcinoma of the mammary gland. The
tumor is different from so-far recognized salivary gland tumor entities.
Received: 25 October 1999 / Accepted: 13 June 2000 相似文献
44.
J. Bijman D. I. Cook C. H. van Os 《Pflügers Archiv : European journal of physiology》1983,398(2):96-102
We have studied the response of the rabbit mandibular main duct perfused in vitro to luminally administered amiloride. The half-maximal inhibitory concentrations (KI) when the duct was bathed in Cl solutions were: for net Na+ transport, 3×10–6 mol l–1; for transepithelial potential difference, 6×10–6 mol l–1; and for transepithelial conductance, 3×10–7 mol l–1. Substitution of the impermeant SO
4
2–
anion for Cl– changed the KI for conductance to 3×10–6 mol l–1. Within Cl–-containing media, the time course of the amiloride effect on potential difference showed an early rapid fall of 10 mV with a half-time 2 s, followed by a slower depolarization of 9 mV, and the conductance change followed the slower component of the potential change. In SO
4
2–
-containing media, the potential difference and conductance changes followed time courses similar to one another. Finally, experiments on the effect of serosal applications of ouabain revealed that, although, in general, ouabain reduced resistance, it caused an increase in resistance in those ducts where the initial resistance was low. We conclude that: i) luminal Na+ transport occurs via amiloride-sensitive, conductive Na+ channels; ii) the Cl– conductance is the major determinant of transepithelial conductance; iii) the first phase of the potential response is due to blocking of the Na+ conductive channels, whilst the slow phase reflects secondary inhibition of an electrogenic Na+ pump; and iv) duct resistance changes are secondary to alterations in intracellular Cl– concentration. 相似文献
45.
目的开发定量分析唾液腺功能及其图象显示的程序。方法应用Aladdin语言编写ROI模块提取各唾液腺及甲状腺区域的摄取数据及本底,用曲线函数生成各ROI的时间-放射性活度曲线,对曲线数据处理,计算唾液腺摄取、排泌指数等指标,然后把图象、曲线及计算结果显示在一个模板内。结果同一幅输出界面图可显示唾液腺的形态、ROI示意图、唾液腺的摄取与排泌功能数值及其曲线,以标准化的显示格式提供给临床医师。不同操作者处理同一资料的功能指标结果基本一致,软件计算的功能指数与图象显示结果及临床诊断基本相符。结论开发的唾液腺功能定量分析软件,程序运行稳定,结果重复性好。 相似文献
46.
大地震创伤后应激障碍患者的心理与神经内分泌变化 总被引:8,自引:0,他引:8
目的 :研究唐山大地震所致慢性创伤后应激障碍患者基础血清皮质醇浓度和地塞米松抑制试验。方法 :唐山大地震所致创伤后应激障碍 3 5例 (研究组 )和 3 3例正常人 (对照组 )接受了基础血清皮质醇水平的测定和地塞米松抑制试验。结果 :两组基础血清皮质醇水平比较差异无统计学显著性 ,各组男女之间基础血清皮质醇水平分别比较差异亦无统计学显著性。两组服用相同剂量的地塞米松后 ,研究组血清皮质醇水平低于对照组和对血清皮质醇的抑制作用高于对照组 ,差异均有统计学显著性。各组男女之间的基础血清皮质醇水平、服用地塞米松后血清皮质醇水平和对地塞米松的抑制率比较差异无统计学显著性。结论 :唐山大地震所致慢性PTSD患者对糖皮质激素的敏感性增高而导致PHA轴负反馈抑制增强 ,无性别差异 相似文献
47.
Secretion of salivary immunoglobulin a in relation to age,saliva flow,mood states,secretion of albumin,cortisol, and catecholamines in saliva 总被引:1,自引:0,他引:1
Salivary immunoglobulin A (IgA) is one characteristic humoral factor of the local immune system in the upper respiratory tract. Epidemiological studies emphasize the importance of secretory IgA in the protection from infections of the upper respiratory tract. However, due to high interindividual variability of secretion of salivary IgA, it remains difficult to define normal ranges. This series of studies focused on identification of factors influencing basal secretion of salivary IgA. The results indicate a significant relationship between age and salivary IgA concentration. Children below 7 years have lower salivary IgA concentration than children above 7 years or adults. Furthermore, a significant inverse relationship between saliva flow and salivary IgA concentration was found. Gender, mood states, salivary albumin, salivary catecholamines, and salivary cortisol were not associated with salivary IgA. It can be concluded that for defining normal ranges of salivary IgA, age and saliva flow have to be considered. 相似文献
48.
49.
Radiotherapy is common treatment for head-and-neck cancer, during which the salivary glands are often included within the radiation field. The most common side effect of this treatment is the development of oral dryness (xerostomia). This study considers the administration of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF or FGF2) at physiological concentrations before and after irradiation in order to repair radiation-induced damage in salivary gland cells. As a preliminary examination of the efficacy of this approach we have characterized the effects of EGF and bFGF on the apoptotic response of 15-Gy irradiated rat salivary glands in vitro. Also, we have developed a controlled-release delivery system to effectively administer the growth factor to the gland since local delivery is essential to avoid unwanted protection of cancer cells. In vitro administration of bFGF prior to and immediately after irradiation partially protected (44%) the rat parotid gland. EGF did not show any significant radioprotective effect on parotid glands after a single 15-Gy irradiation dose. Encapsulation, storage and release of bFGF from biodegradable 50/50 PLGA microspheres did not affect the functionality of the growth factor in vitro. 相似文献
50.
2型糖尿病患者垂体-肾上腺轴的变化与胰岛素抵抗 总被引:2,自引:0,他引:2
目的探讨2型糖尿病患者早期垂体-肾上腺轴的改变与胰岛素抵抗(IR)的关系。方法采用化学发光等方法测定67例新诊断的2型糖尿病患者和33名志愿者(对照组)的血皮质醇(F)和促肾上腺皮质激素(ACTH)(8Am、4Pm和地米抑制后次8Am)以及血清胰岛素(INS)、C肽(C-P)和血糖水平;按HOMA模型计算胰岛素抵抗指数HOM-IR=FINS×FBG/22.5,以此反映2型糖尿病患者IR的情况。结果①2型糖尿病患者8Am血浆F和ACTH、4Pm和地米抑制后次8Am血浆F、血糖、INS、C-P水平以及HOMA-IR均明显高于对照组(P<0.01);②4Pm和地米抑制后次8Am血浆ACTH水平显著低于对照组;③直线相关统计分析显示,皮质醇浓度的升高与空腹血糖升高呈正相关(r=0.48,P<0.01)。与HOMA-IR的升高无直线相关性。结论2型糖尿病患者早期呈现ACTH、皮质醇过度分泌和慢性垂体-肾上腺轴功能紊乱,诱发并加重了糖代谢紊乱和胰岛素抵抗。 相似文献