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81.
The expression of human growth hormone (GH) in female transgenic mice (TM) is accompanied by sterility, whereas females expressing the bovine GH gene are fertile. A light and electron microscopic study was conducted to examine whether expression of these foreign GH genes in mice is associated with structural changes in the ovaries of young adult (3-month-old) or middle-aged (7-month-old) mice. One ovary was serially sectioned for light microscopy, and the contralateral ovary was used for electron microscopy. The numbers of preantral (PAF) and antral (AF) follicles, with and without signs of atresia, as well as the number of corpora lutea (CL), were determined. As expected, body weights of both young and middle-aged TM of either kind were significantly increased over those of their normal littermates. However, the ovarian weights of TM and control mice did not differ. In the 3-month-old TM, the ovaries were grossly normal at the light microscopic level. However, significantly more CL were counted in the ovaries of human GH-TM than in those of the other two groups. The percentage of PAF with signs of atresia was significantly reduced in ovaries of bovine GH-TM compared with the other groups, while the percentages of AF undergoing atresia were significantly different in all groups, with the highest values in normal animals, intermediate ones in human GH-TM, and the lowest in bovine GH-TM. In the ovaries of 7-month-old human GH-TM, conspicuous clusters of large, foamy light cells were present in the cortex and the medulla. Ultrastructurally, these cells appeared as interstitial cells in various stages of degeneration, accumulating cholesterol crystal-like inclusions. Although degeneration of interstitial cells was observed also in the other types of animals, it involved usually only single cells and no cytoplasmic crystal inclusions. Moreover, in the ovaries of 7-month-old human GH-TM the percentages of PAF were significantly reduced and the percentages of AF significantly increased compared with those in the two other groups, which did not differ from each other with respect to these parameters. No significant differences in the numbers of CL were found between the groups. Percentages of atretic PAF were significantly reduced in bovine GH-TM and comparable in the other two groups, while percentages of atretic AF were not different between normal and bovine GH-TM, but were significantly increased in human GH-TM.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
82.
为获取有功能的IV型II类反式激活因子基因 (CIITA IV ) ,诱导肿瘤细胞表达MHCII类分子 ,从IFN γ刺激的THP 1细胞中以RT PCR获得CIITA IV ,将其连接到pGEMT easy载体。对所构建的pcDNA3 1 CIITA IV型表达载体进行反复测序后发现 ,所获得的CIITA IV基因存在结构变异 ,在 2 87位插入了 3个核苷酸TAG ,使 2 86 2 88位的AAG改变成为ATAGAG(2 86 2 90 ) ,并引起其他 8个座位核苷酸 (及推导的氨基酸残基 )发生改变。将表达载体转入原先不表达MHCII类分子的HeLa细胞中 ,检测到所获得的IV型CIITA变异体具有诱导人II类分子HLA DR表达的能力。空载体和CIITA IV基因导入的HeLa细胞中 ,DR阳性细胞百分率分别为 0 0 1 %和 37 6 4 %。该基因已从GenBank得到登录号 ,表明这是一个具有诱导HLA DR分子表达功能的IV型CIITA新基因。  相似文献   
83.
Yun AJ  Lee PY 《Medical hypotheses》2005,65(3):587-590
Lymphoproliferative disorders comprise a heterogeneous group of neoplasms whose behaviors range from indolent to very aggressive. The increased incidence seen in the context of immunodeficiency provides evidence that the host immune system plays a vital role in their pathogenesis. We believe that T-helper (Th)-2 dominant states favor development of lymphoproliferative disorders, including lymphoma, and conversely T-helper (Th)-1 immunity protects against lymphoproliferative disease. The age distribution of lymphomas favors childhood and post-reproductive senescence, suggesting that exposure to these periods of Th-2 bias constitutes a key risk factor for developing the disease. The tendency of lymphomas to arise in Th-2 biased locations such as mucosal interfaces, immunoprivileged sites, and regions of B-cell differentiation may likewise reflect a corresponding spatial predilection. Various clinical conditions or treatments that shift Th1/Th2 balance, including HIV infection, transplant-related immune suppression, and autoimmune disorders, can also influence the status of lymphoproliferative diseases.  相似文献   
84.
目的:探讨HIE患者血中6-keto-PGF1α、NSE水平变化及临床意义.方法:用RIA检测89例HIE患者和32例正常新生儿血中6-keto-PGF1α、NSE水平变化.结果:HIE轻、中、重度组6-keto-PGF1α水平与正常对照组比较,均存在显著性差异(p<0.01),HIE患者轻度组NSE水平与对照组比较无显著性差异(p>0.05),中、重度组NSE水平与对照组比较存在显著性差异(p<0.01),6-keto-PGF1α、NSE二组血中浓度上升与HIE程度呈正相关.结论:HIE患者中6-keto-PGF1α、NSE水平检测,对判断HIE的脑损伤程度、治疗、预后观察,具有重要临床意义和应用价值.  相似文献   
85.
Cancer-associated retinopathy (CAR) is a rare paraneoplastic syndrome, and the recoverin-specific autoantibody is suggested to contribute to the pathogenesis of retinopathy, including apoptosis of retinal cells. Because it is known that CAR(+) cancer patients have a preferable prognosis, we hypothesized that aberrantly expressed recoverin in cancer cells can become a target of cytotoxic T lymphocytes (CTL). Here we tested nine recoverin-derived HLA-A24-binding peptides for their capacity to elicit antitumor CTL. We observed recoverin-specific CTL responses in two HLA-A24(+) CAR(+) cancer patients. In addition, the CTL responses were obtained from three of ten CAR(-) cancer patients and two of six healthy individuals. The CTL precursor frequency of CAR(+) cancer patients and that of CAR(-) cancer patients was higher than that of healthy individuals. Of nine recoverin peptides, R49 (QFQSIYAKF), R49.2 (QFQSIYAKFF), and R64 (AYAQHVFRSF) were discovered to induce the peptide-specific CTL. Taken together, our present data suggest that peripheral activation of recoverin-specific antitumor CTL is likely to contribute to the preferable prognosis of CAR(+) cancer patients. Moreover, in cases other than CAR(+) cancer patients, recoverin may offer the opportunity to design epitope-based immunotherapeutic approaches for treating HLA-A24(+) cancer patients with a recoverin-expressing tumor.  相似文献   
86.
In most cases, while schwannoma is sporadically manifested as a single benign neoplasm, the presence of multiple schwannomas in one patient is usually indicative of neurofibromatosis 2. However, several recent reports have suggested that schwannomatosis itself may also be a distinct clinical entity. This study examines an extremely rare case of probable schwannomatosis associated with intracranial, intraspinal and peripheral involvements. A 63-year-old woman presented with a seven-year history of palpable lumps on both sides of the supraclavicular area and hearing impairment in both ears. On physical examination, no skin manifestations were evident. Facial sensory change, deafness in the left ear and decreased gag reflex were revealed by neurological examination. Magnetic resonance imaging revealed multiple lesions of the trigeminal nerves, acoustic nerves, lower cranial nerves, spinal accessory nerve, brachial plexuses, and spinal nerves. Pathological examination of tumors from the bilateral brachial plexuses, the spinal nerve in the T8 spinal position and the neck mass revealed benign schwannomas. Following is this patient case report of multiple schwannomas presenting with no skin manifestations of neurofibromatosis.  相似文献   
87.
We investigated the effect of beta-adrenergic stimulation on the heart rate and QT interval in syncope children with or without coexisting ventricular arrhythmias (VA). Of the 24 children who presented with syncope or presyncope and showed negative tilt test, 13 were classified into a group with VA and the remaining 11 without VA. The provocative test was performed in bolus infusion and continuous infusion. RR, QT, and QTc intervals on routine 12-lead surface electrocardiogram were obtained during each stage of isoproterenol infusion. In all cases, malignant ventricular arrhythmia and syncope were not induced by isoproterenol provocative test. RR and QT intervals were shortened and QTc intervals were prolonged as the isoproterenol dose was increased in both groups and methods. The QTc interval reached its peak level after the bolus injection of 1.0 microgram and during the continuous infusion of 0.03 microgram/kg/min. The two groups showed no significant difference in the QTc interval change according to the infusion methods. This study indicates that changes in the heart rate and QT interval by beta-adrenergic stimulation were not different according to the coexisting ventricular arrhythmias in syncope children with negative head-up tilt test.  相似文献   
88.
彭鲁英  王云 《解剖学杂志》1990,13(3):230-233
本文研究丁敌枯双对BALB/C雄性小鼠生殖细胞分裂比率及精原细胞染色体畸变的影响。将实验小鼠随机分为三组,即实验组(敌枯双组),阳性对照组(环磷酰胺组)和阴性对照组(双蒸水组)。结果发现:敌枯双能明显诱发精原细胞多倍体率和裂隙率增加,抑制终变期/中期Ⅰ和中期Ⅱ细胞的减数分裂比率,促进精原细胞有丝分裂比率。实验结果还提示:在遗传毒理检测中亚急性实验是必要的,并对实验结果进行了初步讨论。  相似文献   
89.
90.
Brazilin and haematoxylin, plant pigments, were examined for their effects on the Bovine-Lens aldose reductase (LAR)-activity. About 50% inhibition was observed in a concentration of 10 (-4) M-brazilin and 10 (-4) M-haematoxylin, and above 95% inhibition was observed in a concentration of 10 (-3) M-brazilin and 10 (-3)M-haematoxylin. In order to determine the type of inhibition, kinetic studies were also conducted with brazilin and haematoxylin, in which both were found to be noncompetitive inhibitors.  相似文献   
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