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21.
蛇床子水提取液抑瘤作用的实验研究   总被引:13,自引:0,他引:13  
目的 :研究蛇床子水提取液的体内抗肿瘤作用。方法 :通过 S180 肉瘤移植建立荷瘤小鼠模型 ,给予不同剂量蛇床子水提取液后观察 S180 荷瘤小鼠肿瘤生长曲线、血清唾液酸 (SA)、瘤重及小鼠生存天数的变化。结果 :蛇床子水提取液能明显抑制肿瘤生长 ,降低荷瘤小鼠血清 SA水平 ,0 .0 6mg/(g· d) ,0 .1 1 mg/(g· d)、0 .2 1 mg/(g· d)剂量组平均瘤重低于肿瘤对照组 (P<0 .0 5 ) ,抑瘤率依次为 2 3 .2 %、2 9.1 %和 2 4 .8%,且能延长荷瘤小鼠生存天数 (P<0 .0 1 ) ,动物生命延长率依次为 :2 6 .9%、3 4 .8%和 2 6 .6 %。结论 :蛇床子水提取液具有较强的抗肿瘤效应 ,有很好的利用前景 ,值得对其进行深入研究。  相似文献   
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Clinical data of 192 patients with breast cancer with a primary lesion of 2-5 cm (stage II according to the criteria recommended by the UICC) and with histopathologically confirmed positive axillary lymph nodes were analyzed. The patients were divided into three groups: 1) surgical excision alone; 2) surgery plus irradiation; and 3) surgery plus chemotherapy. It was shown that the 5-year survival rates for these groups were 40.5%, 61.0%, and 62.0%, respectively (P less than .05).  相似文献   
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目的 探讨种植受体血管内皮细胞在抗异种血管移植超急排斥反应 (HAR)方面的意义。方法 选用豚鼠→大鼠移植模型 ,先将分离、培养的大鼠动脉内皮细胞种植于去内皮的豚鼠动脉内壁 ,再将此豚鼠动脉植入大鼠体内 ,观察动脉血栓形成时间 ,并采用免疫组化技术检测了 Ig M、C3在移植后豚鼠动脉壁上沉积的情况。结果 已种植大鼠内皮细胞的豚鼠动脉血栓形成时间 (2 0 .3± 4.42 h)较植入大鼠体内的正常豚鼠动脉 (0 .35± 0 .2 84h)以及单纯去内皮豚鼠动脉血栓形成时间 (0 .16 5± 0 .0 77h)显著延长 (P<0 .0 0 1)。免疫组化结果显示 ,植入大鼠体内的正常豚鼠内皮细胞表面有 Ig M和 C3沉积 ,而预先种植大鼠内皮细胞的豚鼠动脉内壁无 Ig M和 C3沉积。结论 在异种供体血管壁上预先种植受者血管内皮细胞 ,可延长移植的异种供体血管通畅时间 ,该技术可能在抗异种血管移植 HAR方面具有重要意义  相似文献   
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烹调油烟致大小鼠肺癌的实验研究   总被引:1,自引:0,他引:1  
[目的]了解烹调油烟(cooking oil fumes,COF)的动物致癌性。[方法]采用动式染毒法给Balb/c小鼠(雌雄各半)吸入COF浓度为9.09、20.65、38.85mg/m^3,染毒1次/1~2d,30min/次,共150次,计8个月;SD大鼠(雌雄各半)吸入COF浓度为6、88、15.06、35.33mg/m^3,染毒1次/2d,30min/次,共191次,计12.5个月。分别制备COF慢性中毒动物模型;两实验均设空白对照组,吸入与实验组相同温度的清洁空气。[结果]COF诱发Balb/c小鼠实验组肺癌总发生率为18、95%(29/153),低、中、高浓度组肺癌发生率分别为15.09%、20、00%和22.00%,与对照组差异均有显著性。但低、中、高三组间差异无显著性(P〉0.05);COF诱发SD大鼠肺癌总发生率为9、10%(9/99),低、中、高浓度组肺癌发生率分别为6.45%、8.57%、12.12%,高浓度组肺癌发生率高于对照组(P〈0.05)。各性别组间肺癌发生率的差别无显著性(P〉0.05)。[结论]COF可以诱导Balb/c小鼠和SD大鼠肺癌,诱发的肺癌主要为肺腺癌(小鼠28/29,大鼠7/9),余为小细胞肺癌。  相似文献   
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The treatment of deep cartilage defects in load-bearing joints is a problem that still has no satisfactory solution. Full-thickness defects of the articular cartilage rarely heal spontaneously, usually leaving damage that can lead to early arthrosis. Techniques currently available for the treatment of chondral defects include abrasion, drilling, micro-fracturing, transplantation of tissue autografts and allografts, and cell transplantation. Osteochondral autograft transplantation is currently the only surgical cartilage repair technique known to lead to the formation of genuine hyaline articular cartilage and its retention at least in the medium term. The Draenert method, in which a water-cooled diamond bone-cutting system is used, is an effective procedure for resurfacing the joints affected by localised cartilaginous defects, even when there is also severe bone loss. Donor-side morbidity can be kept to a minimum by filling the defect caused by harvesting with a press-fit cylinder of cancellous bone covered with periosteum for protection.  相似文献   
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The mechanism by which mechanical strain and estrogen stimulate bone cell proliferation was investigated using monolayer cultures of human osteoblastic TE85 cells and female human primary (first-passage) osteoblasts (fHOBs). Both cell types showed small but statistically significant dose-dependent increases in [3H]thymidine incorporation in response to 17beta-estradiol and to a single 10-minute period of uniaxial cyclic strain (1 Hz). In both cell types, the peak response to 17beta-estradiol occurred at 10(-8) - 10(-7) M and the peak response to strain occurred at 3500 microstrain ((mu)epsilon). Both strain-related and 17beta-estradiol-related increases in [3H]thymidine incorporation were abolished by the estrogen receptor (ER) modulator ICI 182,780 (10-8 M). Tamoxifen (10(-9) - 10(-8) M) increased [3H]thymidine incorporation in both cell types but had no effect on their response to strain. In TE85 cells, tamoxifen reduced the increase in [3H]thymidine incorporation associated with 17beta-estradiol to that of tamoxifen alone but had no such effect in fHOBs. In TE85 cells, strain increased medium concentrations of insulin-like growth factor (IGF) II but not IGF-I, whereas 17beta-estradiol increased medium concentrations of IGF-I but not IGF-II. Neutralizing monoclonal antibody (MNAb) to IGF-I (3 microg/ml) blocked the effects of 17beta-estradiol and exogenous truncated IGF-I (tIGF-I; 50 ng/ml) but not those of strain or tIGF-II (50 ng/ml). Neutralizing antibody to IGF-II (3 microg/ml) blocked the effects of strain and tIGF-II but not those of 17beta-estradiol or tIGF-I. MAb aIR-3 (100 ng/ml) to the IGF-I receptor blocked the effects on [3H]thymidine incorporation of strain, tIGF-II, 17beta-estradiol, and tIGF-I. HOBs and TE85 cells, act similarly to rat primary osteoblasts and ROS 17/2.8 cells in their dose-related proliferative responses to strain and 17beta-estradiol, both of which can be blocked by the ER modulator ICI 182,780. In TE85 cells (as in rat primaries and ROS 17/2.8 cells), the response to 17beta-estradiol is mediated by IGF-I, and the response to strain is mediated by IGF-II. Human cells differ from rat cells in that tamoxifen does not block their response to strain and reduces the response to 17beta-estradiol in TE85s but not primaries. In both human cell types (unlike rat cells) the effects of strain and IGF-II as well as estradiol and IGF-I can be blocked at the IGF-I receptor.  相似文献   
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Contemporary discourse contains numerous examples of use of the concept of culture by social and behavioral scientists. Simple reification, where the speaker makes culture into a thing capable of action exemplifies one usage in public discourse. Some quantitative social scientists attempt to characterize people’s cultural identities by means of a single categorical variable, which often “lumps” people into categories such as “Hispanic” or “Black” that in fact have numerous culturally bounded subcategories. Approaches that emphasize cultural process are preferable to those who attempt to categorize; more complex measures of acculturation help investigators to make convincing analyses of circumstances in which health disparities occur. Examples in which investigators make appropriate use of cultural characterizations demonstrate their utility in investigating health disparities in Haitian American women, injecting and noninjecting drug users, Hispanic youth, and adult Hispanics at risk of HIV infection. Focus on culture in the study of health disparities can identify entanglements between structural factors such as poverty and lack of education and cultural factors such as beliefs about health. Qualitative methods coupled with quantitative methods have great potential to improve investigators’ grasp of cultural nuance while capturing the distribution of qualitatively derived behaviors.  相似文献   
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