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We report on a case of invasive lobular carcinoma of the breast with a previously undescribed cytologic feature. Diff-Quik-stained cytologic preparations showed uniform single cells with prominent coarse cytoplasmic granules. Ultrastructurally, the granules showed features suggestive of autophagosomes and/or degenerative mitochondria. The cytologic differential diagnosis included granulocytic sarcoma, metastatic melanoma, extramedullary hematopoiesis, large granulocytic leukemia/lymphoma, and mast-cell tumor. Adjunctive studies were helpful in the diagnosis of carcinoma. Histologic study of the mastectomy specimen showed classic type of invasive lobular carcinoma.  相似文献   
13.
Thymic mast cells were studied by light and transmission electron microscopy in chicken embryos during organogenesis. Mast cells made their first appearance at day 15. At days 16 and 17, there was a burst of mast cell development with a peak of 278 ± 54 cells/mm2 at day 16. Then, mast cell density decreased until hatching. During the whole embryonic period, about 80% of mast cells localized to the thymic medulla. In the cortex, they were less numerous, and some rare mast cells could be identified in the capsule and septa. Thymic mast cells could be recognized in association with hematopoietic foci, but frequently they grew independently from areas of hematopoiesis and appeared as single cells interspersed among thymocytes, thymic epithelial cells, and interdigitating cells. They were often recognized in close relationship with the scanty and delicate extracellular matrix of the developing gland. Viewed by electron microscopy, mast cells were relatively small cells, with a few secretory granules. Exocytosis was never seen, but, notably, granules emptied in a piecemeal degranulation fashion. This study demonstrates that the chicken thymus is a site of mast cell development during embryogenesis. The high mast cell density we found suggests a possible role for these cells during thymus organogenesis.  相似文献   
14.
In an ultrastructural study of 37 cases of bronchioloalveolar cell carcinoma (BAC), we identified seven cases (19%) in which Langerhans cells (LC) were closely associated with tumor cells. Serum precipitating antibodies against Aspergillus species and/or thermophilic actinomyces were present in five BAC patients whose tumors contained LC and in six patients whose tumors lacked LC. In a simultaneous study we identified marked atypical bronchiolar and alveolar lining cell hypertrophy and hyperplasma in pulmonary eosinophilic granuloma (PEG). Our data plus current information suggesting that PEG is a form of hypersensitivity pneumonitis support our hypothesis that those cases of BAC in which LC are present may arise in localized or diffuse pulmonary scars caused by PEG.  相似文献   
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阿尔茨海默病(AD)是最常见的痴呆形式,目前缺少疾病修饰性的治疗药物。中医理论认为肾精亏虚是AD发生发展的内在机制,补肾益精是中医治疗AD的基本原则,贯穿AD治疗的始终。补肾益智方是治疗AD的临床经验方。补肾益智方治疗AD已有大量文献报道,但补肾益智方缺乏临床应用安全性评价,同时其基础研究薄弱,有效成分不明、多靶点作用机制不清。为阐明补肾益智方多成分、多靶点、多途径治疗AD的作用机制,该文综述了补肾益智方治疗AD的研究进展。进一步收集了16个基于高效液相色谱指纹图谱的补肾益智方主要化学成分,并对其成药性与安全性进行评价。利用基于AD重要病理生理学过程的网络药理学与文献综述相结合的方法,深入分析了补肾益智方靶向胆碱能系统、AD神经病理学特征的有效成分及可能机制。该研究为AD对症治疗、疾病修饰性治疗的药物研发提供了一系列有潜力的先导化合物,并为深入拓展补肾益智方的临床应用提供了理论依据。  相似文献   
17.
目的 :观察心痛安颗粒剂对不稳定性心绞痛患者血小板和凝血系统的作用。方法 :6 0例不稳定性心绞痛患者随机分为心痛安组 (30例 ,常规西药加心痛安颗粒剂治疗 )与对照组 (30例 ,单用常规西药治疗 ) ,观察治疗前后血小板最大聚集率 (Ma% )血小板 α颗粒膜糖蛋白 (GMP- 140 )和 D-二聚体 (D- D)的变化。结果 :治疗后 ,心痛安颗粒组的 Ma% ,GMP- 140和 D- D经治疗后明显下降 ,下降幅度明显大于对照组。结论 :心痛安颗粒剂可能通过抑制血小板聚集、活化和纤维蛋白合成而发挥治疗不稳定性心绞痛的作用。  相似文献   
18.
目的:分析复方苁蓉益智胶囊联合奥拉西坦治疗老年阿尔茨海默病的临床疗效。方法:选取2018年1月至2021年9月北京市隆福医院收治的148例老年阿尔茨海默病患者作为研究对象,采用随机数字表法简单随机化分为对照组和观察组,每组74例。对照组采用奥拉西坦胶囊进行治疗,观察组在对照组的基础上联合复方苁蓉益智胶囊治疗,均治疗3个月。比较2组患者临床疗效、氧化应激指标、炎症介质、病情严重程度、胆碱能神经递质水平、血液流变学指标及简易精神状态量表(MMSE)评分。结果:治疗后,观察组总有效率高于对照组(P<0.05)。与治疗前比较,治疗后2组患者血清超氧化物歧化酶(SOD)、乙酰胆碱(ACh)、胆碱酯酶(AChE)水平、MMSE及画钟试验评分、即刻记忆、回忆、注意力及计算力、地点定向力、时间定向力、语言评分升高,观察组高于对照组(均P<0.05);2组患者血清丙二醛(MDA)、白细胞介素-1β(IL-1β)、核因子κB水平及临床痴呆量表(CDR)评分、全血高切黏度、全血低切黏度、红细胞聚集指数降低,观察组低于对照组(均P<0.05)。结论:复方苁蓉益智胶囊联合奥拉西坦可有效减轻老年阿尔茨海默病患者机体炎症反应和氧化应激反应,缓解患者病情进展,调节神经递质水平和血液流变学,改善其认知功能,具有较好的治疗效果。  相似文献   
19.
Summary Partially purified chromaffin granules (granular fraction), crude mitochondria (mitochondrial fraction) and a microsomal fraction were prepared from bovine adrenals by differential centrifugation and characterized by their catecholamine content, succinate dehydrogenase and glucose-6-phosphatase activity. During isotonic incubation with 0.1 mM 45Ca2+ all fractions showed an uptake of 45Ca2+, which was stimulated by ATP. In addition, after incubation the granular fraction was further fractionated by sucrose density gradient centrifugation (2.0–1.3 M sucrose; 170,000g·60 min). In some of these experiments the granular fraction was incubated simultaneously with 45Ca2+ and [3H](-)noradrenaline to compare the uptake of both. The rate of uptake of 45Ca2+ into the 2.0 M sucrose fraction (characterized by the highest catecholamine content and the lowest succinate dehydrogenase activity) was doubled by ATP. The ATP-stimulated uptake of 45Ca2+ into the 2.0 M sucrose fraction of chromaffin granules was inhibited by N-ethylmaleimide (NEM) (0.1 mM), 2,4-dinitrophenol (DNP) (0.1 mM), azide (1 mM), carbonyl cyanide mchlorophenylhydrazone (CCCP) (20M), atractyloside (50 M), ruthenium red (40 M) and amobarbital (1 mM). This inhibition pattern was different from that of the ATP-stimulated uptake of 45Ca2+ into the microsomal fraction, but it was similar to that of the ATP-stimulated uptake of 45Ca2+ into the mitochondrial fraction. However, the following differences are incompatible with the view that a mitochondrial contamination, with a highly active uptake, is responsible for the ATP-stimulated uptake of 45Ca2+ into the 2.0 M sucrose fraction of chromaffin granules: a) The uptake of 45Ca2+ into the mitochondrial fraction was insensitive to 1 mM amobarbital, whereas this agent inhibited the uptake of 45Ca2+ into the 2.0 M sucrose fraction of chromaffin granules. b) Replacement of ATP by succinate stimulated the uptake of 45Ca2+ into the mitochondrial fraction only. c) The dependence of the ATP-stimulated uptake of 45Ca2+ on the concentration of ATP (0.1–5 mM) was determined: while uptake into the 2.0 M sucrose fraction of chromaffin granules exhibited saturation kinetics, that into the mitochondrial fraction was linearly related to the concentration of ATP. Interestingly, uptake of 45Ca2+ into those fractions of chromaffin granules that are known to be contaminated with mitochondria (1.6 M sucrose fraction) exhibited bot a saturable and a nonsaturable component. d) The uptake of 45Ca2+ into the mitochondrial fraction was more sensitive to 0.1 mM DNP than the uptake of 45Ca2+ into the 2.0 M sucrose fraction of chromaffin granules.The comparison of the ATP-stimulated uptake of 45Ca2+ with that of [3H](-)noradrenaline into the 2.0 M sucrose fraction of chromaffin granules revealed that amobarbital, N,N-dicyclohexylcarbodiimide (DCCD), DNP and increasing concentrations of ATP had the same influence on both uptake processes. From our results we conclude that an inherent, ATP-stimulated uptake of 45Ca2+ exists in chromaffin granules. The effects of agents on the uptake of 45Ca2+ and/or [3H](-)noradrenaline into chromaffin granules are discussed with regard to the granular uptake mechanisms.This work was supported by the Deutsche ForschungsgemeinschaftSome results were reported at the 18th Spring Meeting 1977 of the Deutsche Pharmakologische Gesellschaft (Burger and Häusler 1977)  相似文献   
20.
Primary infiltrating signet ring carcinoma of the eyelids   总被引:1,自引:0,他引:1  
A 61-year old man presented with a five-year history of a swelling initially developing in his right lower lid that progressed to involve the lateral canthal skin and eventually the upper lid and anterior orbit. He was discovered to have an infiltrating, poorly differentiated, mucin-producing carcinoma. Systemic work-up failed to disclose a visceral malignancy, and it was concluded that his tumor was primary in the lids, arising from an adnexal sweat gland. Three other reports in the literature also share almost identical clinical and pathologic features, in that all of the earlier reports dealt with middle-aged or elderly men who had diffusely indurated lids. Histopathologically, the tumor cells grow diffusely in a sclerotic stroma, and resemble the "histiocytoid" variant of metastatic breast carcinoma to the lids in women. Ultrastructural studies in our case point toward an apocrine origin, although earlier authors have favored an eccrine origin. Despite its indolent clinical course, the tumor is capable of producing regional and distant metastases on long-term follow-up. Complete local excision, possibly necessitating radical surgery, is probably the preferred method of treatment, but local radiotherapy may have a beneficial effect in retarding spread of the disease.  相似文献   
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