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991.
目的 探讨凝血酶对培养的大鼠脑星形胶质细胞毒性损害及水蛭提取液对其的保护作用. 方法 建立体外实验即大鼠脑星形胶质细胞培养实验模型,相差显微镜观察细胞生长状况.MTT法筛选水蛭提取液的有效浓度.星形胶质细胞分为水蛭提取液治疗组与凝血酶对照组,测定培养上清液酸脱氢酶(LDH)活性(细胞死亡的标志).免疫组化法观察它们的HSP70和TGFβ-1的表达. 结果 (1)一定浓度范同(1~100 U/mL)的凝血酶对星形胶质细胞有毒性作用,且随凝血酶剂量的增大,它对星形胶质细胞的毒性作用相应增加(F=118.65,P=0.000).(2)一定浓度范围内(0.25~4 mg/μL)的水蛭提取液能明显减轻10 U/mL凝血酶对星形胶质细胞的毒性作用(F=156.08,P=0.000),且随水蛭提取液浓度的增大,保护作用增强,还可促进星形胶质细胞HSP70和TGFβ-1的表达. 结论 水蛭提取液能促进星形胶质细胞增生,增强它们的HSP70和TGFβ-1表达,从而明显抑制凝血酶对星形胶质细胞的毒性作用. 相似文献
992.
N. V. Isaykina T. V. Perevozchicova G. I. Kalinkina 《Bulletin of experimental biology and medicine》2008,146(2):223-225
The formulation of medicinal herbal tea Echinosol was developed. Immunotropic properties of aqueous-alcohol extract Echinosol
were studied. This extract (300 mg/kg) had a stimulatory effect on the following parameters: formation of T cell precursors
and production of T cell effectors; migration of lymphocytes, monocytes and neutrophils into the blood; digestive activity
of neutrophils; migration of monocytes and lymphocytes into the peritoneal exudate; expression of C3b receptors on macrophages; phagocytic capacity of cells due to the existence of C3b receptors; number of antibody-producing cells in the spleen; and synthesis of immunoglobulins.
Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 146, No. 8, pp. 188–191, August, 2008 相似文献
993.
Z H Marcus E V Hess J H Herman P Troiano J Freisheim 《Journal of reproductive immunology》1979,1(2):97-107
The effect of male genital tract components (human spermatozoa, intact and chromatographed seminal plasma fractions) on in vitro cell-mediated immune reactions was examined. Their addition to PHA-containing lymphocyte cultures resulted in a marked degree of inhibition of DNA synthesis, the response varying with the fractions employed. The interference by such components with a terminal cell event during blast transformation was suggested by the failure of stimulated cultures to incorporate thymidine irrespective of the time during the incubation period at which the constituents were added. Seminal plasma and sperm extracts were also shown to inhibit T-cell associated E-rosette formation. The inhibitory properties of genital fractions remained unaltered after repetitive freeze-thaw cycling when tested in the transformation and E-rosette assays. Heating to 100 degrees C modified the response with some of the fractions. 相似文献
994.
脑泰方提取物抗肿瘤坏死因子诱导人脐静脉内皮细胞凋亡的研究 总被引:1,自引:1,他引:0
目的 观察重组人肿瘤坏死因子α(rhTNF-α)诱导人脐静脉内皮细胞(HUEC)凋亡及中药脑泰方提取物(NTE)的作用。方法 将融合生长的HUEC随机分为空白对照组(正常培养,不加rhTNF-α)、NTE对照组(加中剂量NTE,不加rhTNF-α)、rhTNF-α组(仅加100ngmL rhTNF-α)和NTE高、中、低剂量组(加100ng/mL rhTNF-α和6mg/mL、2mg/mL、0.67mg/mL NIE),观察rhTNF-α作用24h后内皮细胞吖啶橙/溴乙啶双重荧光染色和凋亡细胞计数。结果 荧光显微镜下可见,空白对照组和NTE对照组HUEC为正常结构的活细胞、染色质主要着亮绿色,凋亡细胞率分别为14.0%和14.5%;rhTNF-α组与NTE低剂量组细胞大多呈均匀橙色,染色质多被染为橘红色,以固缩状或圆珠状为主,凋亡细胞率分别为75.0%和63.5%;NTE高、中剂量组细胞多呈亮绿色,凋亡细胞率分别为43.5%和53.0%。结论 一定浓度的肿瘤坏死因子引起的内皮细胞损伤主要表现为细胞凋亡,脑泰方提取物可明显抑制这种凋亡的过度发生。 相似文献
995.
大蒜提取物与大蒜素抗深部真菌的实验研究 总被引:11,自引:0,他引:11
应用微量稀释法,以大蒜提取物在体外对60株深部真菌测定了50%最小抑制浓度(MIC_(30))、90%最小抑制浓度(MIC,0)、50%最小杀真菌浓度(MFC_(50))和90%最小杀真菌浓度(MFC_(?))。体外对白色念珠菌的时间-杀菌动力学表明大蒜提取物主要影响真菌生长的迟缓期。经比较合成的大蒜素抗深都真菌的作用更强于大蒜提取物,但是全血细胞韶迅速降低两者的抗真菌活性。 相似文献
996.
救必应正丁醇提取物对血压及心率影响的实验研究 总被引:1,自引:0,他引:1
救必应正丁醇提取物对不同状态下血压及心率作用研究结果表明,静脉注射本品对正常大鼠及夹闭颈总动脉升压大鼠均有显著降压作用,血压下降百分率尤以后者更为明显,持续时间更为长,且有减慢心率的作用。而对失血性低血压大鼠无明显影响,十二指肠灌注本品亦可使血压显著下降,而对心率无明显影响。提示本品具有明显降压和升压状态下减慢心率的作用。 相似文献
997.
Yasuo Oyama Lumi Chikahisa Toshiko Ueha Kaori Kanemaru Katsuhiko Noda 《Brain research》1996,712(2):349
Effect of Ginkgo biloba extract was examined on dissociated rat cerebellar neurons suffering from oxidative stress induced by hydrogen peroxide using a flow cytometer and ethidium bromide. Hydrogen peroxide at a concentration of 3 mM increased the number of neurons stained with ethidium (presumably dead neurons) in a time-dependent manner. Pretreatment of neurons with G. biloba extract (10 μg/ml greatly delayed a time-dependent increase in number of dead neurons during exposure to hydrogen peroxide. It was true, but less effective, in the case of treatment with G. biloba extract immediately or 60 min after start of oxidative stress. Results implicate G. biloba extract as a potential agent in protecting the neurons suffering from oxidative stress induced by hydrogen peroxide. 相似文献
998.
Earthworm capsule is an extract from earthworm made in our laboratory.From1986 to 1989,486 patients with carcinoma of esophagus or lung were randomly divided into 2groups,one group received radiotherapy alone(control group)and the other radiotherapycombined with earthworm capsules(treatment group).All cases were diagnosedpathologically or cytologically.In a two-month treatment course,earthworm capsuleswere given orally twice a day,2~3 capsules each time,each capsule containing 60 mg ofthe extract.Compared with the control group,the CR(complete remission)rate andCR+PR(partial remission)rate in patients with carcinoma of esophagus treated byradiotherapy in combination with earthworm capsule increased 9.7%(P<0.01) and 9.6%(P<0.05),while in patients with carcinoma of lung,they increased 10.6%(P<0.05)and13.5%(P<0.05),respectively.The earthworm capsule caused irritation in the alimentarytract,the patients displaying slight nausea and vomiting(16.7% in thecombination treatment group and 10.0% in the control group).However,these side ef-fects could be alleviated when capsules were taken after meal or with honey concomitantly.No deleterious effects on the heart,liver,kidney,skin,hematopoietic or nervous systemwere seen. 相似文献
999.
百路达对小鼠学习记忆行为的影响 总被引:1,自引:0,他引:1
百路达是国内新研制的银杏叶制剂,本文采用跳台法及避暗法初步探讨了百路达对小鼠学习记忆行为的影响。本实验结果表明,百路达能明显提高正常小鼠学习记忆成绩、改善NaNo2记忆缺损模型鼠的记忆,其作用较脑复康强25倍以上,认为百路达是从植物中提取出来的安全、可靠并高效的促智药物,具有推广价值。本文尚简单探讨了其促智的可能机制,并对两种学习记忆实验方法作了比较。 相似文献
1000.
The Allergy Pricker 总被引:2,自引:2,他引:0
Hans-Jørgen Malling Connie Engelund Andersen Maj-Britt Boas Frida Holgersen Erik P. Munch Bent Weeke 《Allergy》1982,37(8):563-567
Skin prick test has advantages over other diagnostic tests in allergy, and attempts to increase the reproducibility are warranted. A standardised disposable precision needle with a needle point of 1.0 mm has recently become available. Based on 960 tests with histamine and grass pollen ( Phleum pratense ) the reproducibility of the skin prick weal area was calculated. Using histamine 10 mg/ml and grass pollen (1000 and 5000 PNU) A significantly lower coeffcient of variation was found compared with a stadard blood lancet with a point of 4 mm. The mean weal reaction is reduced to about 80% of the size obtained with the blood lancet. Testing with the precision needle resulted in a significantly reduced incidence of bleedings. The precision needle simplifies the skin test and does not require as much skill as other needles, and is recommended for both routine tests and the biological standardization of allergen extracts. 相似文献