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21.
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
22.
S P Hammar D Bockus F Remington K O Hallman R H Winterbauer L D Hill D E Bauermeister H W Jones R P Mennemeyer R F Wheelis 《Ultrastructural pathology》1980,1(1):19-37
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
23.
J. Allan Tucker 《Ultrastructural pathology》1993,17(3):279-286
Classically, ultrastructural examination of alveolar soft part sarcoma reveals large, dramatic, rhomboid to needlelike crystals with a characteristic substructure. In this study of four cases of alveolar soft part sarcoma, only two exhibited large crystals, which were rare. All four cases, however, exhibited round, electron-dense granules, and in the two cases without large crystals these granules rarely exhibited elongation with the characteristic substructure of alveolar soft part sarcoma that permits definitive diagnosis. Two of these cases had been previously studied at other institutions, where crystals were not identified ultrastructurally and electron microscopy was considered noncontributory. Large crystals, then, may be rare or absent in alveolar soft part sarcoma. Careful search may be necessary to find granules with the characteristic periodic substructure. 相似文献
24.
Four tumors with the clinical and light microscopic features of Ewing's sarcoma contained cells that possessed to varying degrees ultrastructural features suggestive of neuroblastoma. These neoplasms were considered to be Ewing's sarcoma of bone by radiologic examination and on clinical grounds, and light microscopy was consistent with the diagnosis in every case. It is suggested that the ultrastructural morphology of Ewing's sarcoma is broader than had been supposed and that the presence of dendritic processes in a small cell tumor of bone should not exclude the diagnosis of Ewing's sarcoma. 相似文献
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山药配方颗粒由山药饮片经水煎煮提取、分离、浓缩、干燥、制粒而成,具有调剂简单、使用方便、免煎易服等优势。然而,因山药富含淀粉与黏液质类成分,其提取物粉末与配方颗粒溶化性差,在5 min内难以完全溶化或分散,不溶物即使在水中静置24 h也难以完全溶散,影响了配方颗粒的质量评价与患者的服药心理。因此,通过研究山药提取物及其配方颗粒的溶化过程与机制,发现山药特殊的化学组成、高温提取过程中淀粉的变性及其与蛋白质等物质的复合、喷雾干燥过程中“衣膜”的收缩形成等因素综合叠加,最终形成“衣膜”包覆淀粉粒的特殊微观结构,是山药配方颗粒溶化性差的根本原因。基于课题组前期对粉体结构-性质-功能的研究,笔者提出采用粉体改性工艺改善山药配方颗粒溶化性的技术策略,并通过实验证明改性处理后的山药配方颗粒能在2 min内实现全部溶散,解决了该技术难题,可为其他类似品种的溶化性改善提供借鉴,推动中药配方颗粒产业的高质量发展。 相似文献
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心痛安颗粒剂对不稳定性心绞痛患者血小板功能及凝血系统的影响 总被引:2,自引:0,他引:2
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
29.
目的 为加快实现中药生产过程中对中药配方颗粒的质量控制,从粉体物料属性出发,探究其对水提工艺下干法制粒的中药配方颗粒溶化性影响机制。方法 以60种中药配方颗粒及中间体混合粉为研究对象,通过对各品种混合粉粉体属性进行测定,建立粉体物性参数与颗粒溶化性关联模型。采用二维矩阵热点图对各品种间及物性指标间相似性进行分析,结合系统聚类分析对其进行归类,并运用多元统计方法初步筛选影响水提工艺下中药配方颗粒溶化性的关键因素。结果 各品种间粉体物性参数相关系数在-0.951~1.000,并按照各品种物理属性大致可以分为5类,结合变量投影响应值(variable importance for the projection,VIP)、自变量回归系数与方差膨胀因子(variance inflation factor,VIF)分析,最终筛选出其休止角(α)、含水量(HR)、吸湿性(H)与比表面积(SSA)4个指标为影响中药配方颗粒溶化性的关键物料属性(critical material attributes,CMAs)。结论 基于中药粉体物料属性与数据分析初步探寻影响水提条件下干法制粒的中药配方颗粒的溶化性机... 相似文献
30.
参芍颗粒对犬血液流变学的影响 总被引:1,自引:0,他引:1
目的:观察参芍颗粒对结扎犬冠状动脉前降支造成血瘀症模型的血液流变学的影响。方法:采用结扎犬冠状动脉前降支造成血瘀症模型,于造模前、造模后15,30,60,90min分别股静脉采血测定血液流变学指标、体外血栓长度、血小板粘附率和全血粘度(切变率为5-200/s)。结果:参芍颗粒可缩短血栓长度、降低全血粘度、血小板粘附度,抑帛血栓形成。结论:参芍颗粒有改善实验性犬血瘀症的血液流变学指标的作用。 相似文献