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1.
金地鼠颊囊癌前病变的细胞增殖动力学研究   总被引:2,自引:0,他引:2  
目的研究口腔上皮组织癌和癌前病变的细胞动力学变化特征。方法采用Saley的DMBA涂布诱导法,建立金地鼠颊囊癌前病变模型,并用溴脱氧尿苷流式细胞动力学检测方法,对30只叙利亚种金地鼠进行分组对照研究。结果涂药组光镜下的细胞病变程度随涂药时间延长而逐渐加重,而空白对照组无变化;FCM检测显示涂药组与对照组在S期阳性细胞检出率存在显著差异。即使在光镜下表现为轻度不典型增生时,FCM检测结果也有显著差别。结论金地鼠颊囊癌前病变具有细胞异常增殖的细胞动力学特征  相似文献   
2.
等比分配二次混合的方法研究   总被引:1,自引:0,他引:1  
陈易彬  陈佳希 《中成药》2007,29(9):1298-1302
目的:建立等比分配二次混合方法,并使此类混合合理化。方法:提出等比分配二次混合方法的基本构架,借助数学工具,运用推理和实验验证的方法进行方法研究。结果:建立了等比分配二次混合方法,实验证明此方法可行。结论:等比分配二次混合法是一个可用于工业化生产,既科学合理又经济可行的特殊混合方法。  相似文献   
3.
癌变的早期诊断对提高疗效具有特殊意义,为了寻求简捷,高效,超前,可靠的诊断方法,实验以DMBA(二甲基苯并蒽)诱导的金地鼠颊囊致癌模型为对象,以PCNA(增殖细胞核抗原)BrdV(溴脱氧尿嘧啶)等免疫组化技术为手段;以光镜观察诊断为对照,对三种观察结果进行相关分析,发现三者间有高度显著的相关性,证实了免疫组化方法在癌变诊断中有一定的参考价值,实验还发现PCNA和BrdU检测结果比较每天敏感,简捷,  相似文献   
4.
自1992年3月至1994年5月,对中原地区4个省20多个县(市)近200个单位33555名20~75岁的已婚妇女,进行妇科疾病发生情况与年龄、职业、文化、月经、孕产等五种因素关系的调查分析。在33555名妇女中,患病者22370人,总患病率为66.67%,查出妇科疾病42种,计76974例次。结果证明:以25~35岁年龄组发病率最高,其中以内生殖器炎症为主;职业以经商者发病率高,特别是性病患者高于其他职业者二倍以上;文化程度以小学、初中者发病率高,尤其宫颈炎更明显;月经情况:随着经前期紧张综合征的加重,更年期综合征发病率增高;孕产次数越多,患病率越高。本次调查未发现宫颈癌,进一步证明我国对妇女保健工作的关心和重视。  相似文献   
5.
Background: The porphyrin concentrations of the Harderian glands of Syrian hamsters show marked sexual differences, with male levels being much lower than those of females. Porphyrinogenesis is inhibited by androgens, so orchidectomy leads to elevated male porphyrin concentrations; however, a number of other procedures (some of which also lower androgen levels) prevent this. We studied the effects of short-day photoperiods and melatonin on Harderian porphyrin concentrations. Methods: Intact, castrated, or pinealectomized hamsters of both sexes were exposed to long-day or short-day photoperiods. Intact or castrated hamsters were given melatonin injections in the morning or the afternoon, or were given beeswax pellets containing melatonin. After a variable period, Harderian glands were dissected and porphyrins were measured. Results: Prolonged short-day exposure (13 weeks) led to increased Harderian porphyrin concentrations and this rise was prevented by pinealectomy. The rise in Harderian porphyrins following short-day exposure was small, compared with that following castration. Short-day photoperiods also prevented the rise in porphyrin levels associated with castration and this effect was prevented by removal of the pineal. Melatonin injections, whether given in the morning or in the afternoon, had no effect on Harderian porphyrin concentration of castrated male hamsters. Continuous release melatonin pellets reduced the postcastrational rise in porphyrin levels in one experiment, while having no effect in another. In female hamster, neither short photoperiods nor melatonin pellets influenced Harderian porphyrin concentrations. Conclusions: These results suggested that a factor from the pineal gland helps maintain the low levels of porphyrin which are characteristic of male Harderian glands, despite the decrease in androgen levels which typically results from exposure to short days. Morning and afternoon injections of melatonin and continuous release melatonin pellets failed to resolve the question of whether this pineal factor is melatonin. Our results demonstrated that low male and high female porphyrin levels are maintained in Syrian hamsters, despite seasonal variations in the hormonal milieu, suggesting that these sexual differences are important for the (still unestablished) function of the Harderian glands in this species. © 1994 Wiley-Liss, Inc.  相似文献   
6.
Effects of aging on estrous cycles and LH release in response to luteinizing hormone releasing hormone (LHRH), castration, and estradiol benzoate were studied in the female golden hamster (Mesocricetus auratus). About 80% to 90% of female golden hamsters still cycled regularly when reaching 19–22 months of age. However, some animals showed age-induced irregularity of the estrous cycle which included an interruption of complete absence of estrous vaginal discharge. Young female hamsters (3–5 months) had significantly (p<0.01) higher basal LH concentration than old animals (19–22 months) in the morning of each stage of estrous cycle. LHRH elicited about 20–30 fold increase in serum LH concentrations in both young and old hamsters. No significant difference in LH release was observed between young and old hamsters in response to LHRH. In acyclic hamsters, the peak of LH release in response to LHRH was delayed. LHRH-induced LH release was greater in the morning of proestrus than during diestrus in both young and old hamsters. LH increase was significantly greater in the young than in old hamsters on the 13th and 15th day after castration. However, positive feedback stimulation of LH release by estradiol benzoate was the same in both young and old hamsters. These results indicate that in the female hamster, LH response to acute stimuli such as LHRH and estrogens is the same in the young as in the old animal and that circulating basal LH concentration may decrease or its degradation or clearance may increase during the aging process in female golden hamsters. Irregularity of estrous cycles in aging hamsters may be related to delayed responsiveness of pituitary LH to LHRH stimulation.  相似文献   
7.
目的:利用黄金数比例规律找出环境物理因子对人体的最佳条件:方法:人体的相当一部分内容与黄金数有着密切的联系,为此把复杂的人体可以简化为比例加破缺的比例实体;环境物理因子:如环境温度、湿度、环境光波和声波以及环境气压和氧分压,当它们处在黄金数比例附近时,会在人体产生和谐合柏作用。结果:环境物理因子选择在黄金数比例附近时,在心理上产生美和舒适感。已经发现,当精神愉快时,人脑电波频率下限(8Hz)和上限(12.9Hz)之比恰为黄金数。结论:环境物理因子的最佳条件是可以选择的。  相似文献   
8.
Chronic effects of 4-nitroquinoline 1-oxide (4 NQO) on the lungs of Syrian golden hamsters were studied. 4 NQO was subcutaneously injected weekly for 3 weeks at a dose of 20 mg/kg body weight. The animals were sacrificed at the 65th and 80th experimental weeks. Two cases of pulmonary adenomas were demonstrated in the 10 4 NQO-treated animals at the 80th week, and the tumor cells contained cytoplasmic lamellar inclusion bodies. In a previous study, we reported 4 NQO- induced pulmonary endocrine cell hyperplasias in the 4 NQO-treated hamster after the 20th experimental week (Jpn. J. Cancer Res., 77,1986). In the present study, 12 pulmonary endocrine cell hyperplasias were recognized in serial sections of the 24 treated animals. The hyperplastic lesions showed positive immunoreactivity to calcitonin. The hyperplastic lesion did not develop to pulmonary endocrine cell neoplasm. ACTA PATHOL JPN 38 : 1097∼1104, 1988.  相似文献   
9.
目的 :为控制和预防骑自行车人与行人的车祸伤害提供依据。方法 :采用描述流行病学方法 ,对 1996年郑州市机动车与骑自行车人和行人相撞的车祸资料进行分析。结果 :骑自行车人与行人的车祸伤害人数占该年总车祸伤害人数的 37.1% ,死亡人数占总死亡人数的 46 .6 % ,伤亡人员多为青壮年。骑自行车人与行人的车祸伤害主要发生在城市主干道、混合式道路、无交通控制方式的交通环境中 ;引起这类伤害的主要原因是驾驶员疏忽大意 ,骑自行车人抢道行驶和突然猛拐 ,行人违章穿行车行道。结论 :骑自行车人与行人车祸伤害是车祸伤害的重要组成部分。致伤原因是人们的交通安全意识差 ,没有按照交通规章行驶。因此 ,应加强交通法规的宣传和教育 ,提高人们的交通安全意识  相似文献   
10.
目的:探讨影响贲门癌患者生存时间的影响因素。方法:收集236例贲门癌患者临床资料和随访资料,使用单因素Log-rank检验、Cox比例危险模型对影响预后的因素进行单因素、多因素回归分析。结果:肿瘤长度、淋巴结转移、组织病理学类型和TNM分期对患者的预后有影响。结论:早发现、早治疗是提高患者生存率的关键。  相似文献   
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