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171.
新生鼠脑损伤后松果体细胞的一氧化氮合酶与细胞凋亡关系的初步研究 总被引:1,自引:0,他引:1
为了探讨新生鼠发生缺氧缺血性脑损伤时松果体细胞的诱生型一氧化氮合酶 ( i NOS)表达与松果体细胞凋亡及形态学改变的关系 ,用 7日龄新生 Wistar大鼠 ,结扎左侧颈总动脉 ,术后 2 h吸入 8%浓度氧 2 h,建立新生儿缺氧缺血性脑病模型( HIBD)。分别于建模后 0 h、2 4h、48h处死动物 ,剥取松果体 ,观察松果体细胞的 i NOS表达及细胞凋亡 ,电镜观察松果体形态学改变。结果表明 :( 1)新生鼠脑损伤后松果体的 i NOS在 0 h、2 4h含量与对照组相比明显升高 ;( 2 )脑损伤后松果体凋亡细胞早期明显增多 ,尤以 0 h、2 4h为主 ;( 3)电镜观察 :脑损伤后松果体的形态学也以 0 h、2 4h改变为明显 ,出现线粒体明显肿胀、粗面内质网极度扩张、细胞变性。提示 :( 1)新生鼠缺氧缺血性脑损伤后 0 h、2 4h松果体细胞的 i NOS表达增加 ,以后逐渐下降 ,48h表达减少。 ( 2 ) TUNEL法原位检测细胞凋亡与 i NOS表达同步改变 ,i NOS表达对细胞凋亡有促进作用。 ( 3) i NOS表达和细胞凋亡参与了新生鼠缺氧缺血性脑损伤后松果体细胞形态学改变 相似文献
172.
Ryohei Katoh Koichi Suzuki Akihiro Hemmi Akira Kawaoi 《Virchows Archiv : an international journal of pathology》1993,422(4):301-306
To elucidate the significance and nature of calcium oxalate crystals in the thyroid, we studied these crystals clinicopathologically and immunohistochemically in 182 normal thyroids from patients autopsied within 5 h of death. Under polarized light, calcium oxalate crystals showed brilliant birefringence and were invariably found within the colloid. The crystals were found in 73.1% of all cases but were more prevalent and denser in older individuals, with the highest prevalence (85.2%) being observed in those over 70 years of age. No crystals were seen in those under 10 years of age. Although underlying diseases seemed to have little influence, post-mortem delay apparently affected the prevalence and density of occurrence since the crystals tended to disappear with hours after death. An immunohistochemical study using anti-thyroid hormone antibodies revealed that the crystals were within negatively or weakly stained colloid and were not common in strongly stained colloid. These findings support the hypothesis that the occurrence of calcium oxalate crystals in normal human thyroid is associated with a low functional state of the thyroid follicles. 相似文献
173.
Reiji Haba Shoji Kobayashi Hiroshi Miki Eiichiro Hirakawa Kousuke Saoo Takayuki Iwai Seiji Mori Masaki Ohmori 《Pathology international》1993,43(12):774-778
A case of polymorphous low-grade adenocarcinoma (PLGA) in the submandibular gland is reported. A 72 year old woman presented with a 5 year history of a gradually expanding tumor in the submandibular region. The surgical specimen revealed a relatively well demarcated tumor, 35 × 35 × 20 mm in size. Macroscopically, necrosis and hemorrhage were not seen in the solid tumor. Histologically, the tumor growth pattern was variable, composed of tubular, papillary, solid, trabecular and cribriform structures. Immunohistochemically, some tumor cells were positive for epithelial membrane antigen (EMA), S-100 protein, keratin, and carcino-embryonic antigen (CEA). Electron microscopically, prominent microvilli projected into the luminal spaces, and basal lamina and hemidesmosomes were seen in the tumor cells adjacent to the connective tissues. The submandibular gland is an extremely rare location for PLGA. To the authors' knowledge, this is the first case of its kind reported in the English literature. 相似文献
174.
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
175.
卵巢切除对大鼠肾上腺雌激素受体亚型表达的影响 总被引:2,自引:0,他引:2
目的通过对去卵巢大鼠雌激素受体(ER)亚型在肾上腺表达的观察,研究去卵巢对大鼠肾上腺功能影响的机制。方法选择成年Wistar大鼠20只,10只为假手术组,10只为模型组(去卵巢组),6周后处死大鼠,分离摘取肾上腺,称重后常规石蜡包埋切片,分别进行ERα、ERβ抗体的免疫组织化学染色,并取动物血清测量雌二醇(E2)和促卵泡生成素(FSH)的含量。结果1.ERα与ERβ在大鼠肾上腺均有表达,主要分布在肾上腺皮质部,以球状带和束状带为主,网状带有少量分布,ERβ的表达强于ERα。2.ERβ在大鼠模型组的表达强于假手术组,有统计学意义,ERα在模型组的表达略强于假手术组,但无统计学意义。3.卵巢切除后,大鼠血清FSH升高,E2下降,与假手术组相比,有显著差异。结论卵巢切除可影响雌激素受体在大鼠肾上腺的表达,尤其是对ERβ表达的影响较为显著。卵巢切除能够减少大鼠血清雌激素的分泌,使垂体反馈性的增加FSH的分泌。 相似文献
176.
Isolation and radiation hybrid mapping of a dinucleotide repeat polymorphism at the human calcium-sensing receptor (CASR) locus 总被引:2,自引:0,他引:2
Kazuhiro Tsukamoto Ikuyo Watanabe Tadayoshi Shiba M. Emi 《Journal of human genetics》1998,43(4):280-282
Calcium-sensing receptor (CASR) in parathyroid gland regulates calcium homeostasis by sensing decreases in extracellular
calcium levels and effecting an increase in secretion of parathyroid hormone. A polymorphic dinucleotide (CA) sequence was
isolated from a genomic clone containing the human CASR gene and was mapped to 3q13.3–q21. This polymorphism will be useful in the genetic study of disorders affecting calcium metabolism,
such as hypercalcemia, hypocalcemia, osteoporosis, hyperparathyroidism, and hypoparathyroidism.
Received: June 2, 1998 / Accepted: June 24, 1998 相似文献
177.
Hypothalamic neurons producing growth hormone-releasing factor (GRF) have been characterized by immunohistochemistry in monkey hypothalamus, using an antiserum raised against hpGRF1-40, a peptide with GRF activity isolated from a human pancreatic tumor. Cell bodies with hpGRF immunoreactivity were found in arcuate and ventromedial nuclei. From these neurons, bundles of fibers innervate median eminence and appear to terminate in contact with portal vessels. In addition to median eminence, hpGRF immunoreactive fibers were found mostly in the anterior hypothalamus and the arcuate and ventromedial nuclei where they give perineuronal endings. These results correlate with earlier physiological data on hypothalamic control of growth hormone secretion and suggest that GRF is also involved in interneuronal relationships related or unrelated to neurohumoral control of pituitary secretions. 相似文献
178.
179.
A case of mixed medullary follicular carcinoma of the thyroid is reported. Grossly, the tumor was a solid, grayish white, well circumscribed mass without lymph node metastasis. Microscopically, the tumor showed both medullary and follicular areas. The follicular areas occupied discrete portions of the tumor, and were considered to be neoplastic. Tumor cells in the medullary area were polyhedral or spindle-shaped. There was no amyloid deposition within the tumor. Immunohistochemically, tumor cells in the medullary area were positive for calcitonin and negative for thyroglobulin. Some cells lining the follicles were positive for thyroglobulin. By electron microscopy, two types of tumor cell were observed. One type contained numerous cytoplasmic secretory granules, whereas the other type had few granules and showed a prominent rough endoplasmic reticulum. These findings suggested that this mixed medullary follicular carcinoma of the thyroid presented neoplastic changes within a common cell lineage. 相似文献
180.