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61.
人参银杏复方制剂对缺氧复氧后大鼠海马CA1区GABA、Glu表达的影响 总被引:2,自引:0,他引:2
目的:探讨人参银杏复方制剂对缺氧复氧后海马CAI区神经元的保护作用机制。方法:应用低压氧舱仿海拔8000米高空缺氧模型,采用免疫组织化学及免疫荧光方法并结合图像分析等技术,观察预防性应用人参银杏复方制剂对缺氧24h复氧0h、24h时段海马CAI区GABA、Glu表达的影响。结果:缺氧24h复氧卟组海马CAI区GABA免疫反应阳性神经元数量、Glu免疫反应阳性神经元荧光强度分别较常氧对照组减少和减弱,复氧24h后上述变化更加明显。预防性应用人参银杏复方制剂后海马CAI区GABA免疫反应阳性神经元数量在复氧0h和24h时较常氧对照组多,以复氧0h时增加最明显;Glu免疫反应阳性神经元荧光强度在复氧0h、24h时段也较缺氧复氧实验组相应时段增加。结论:人参银杏复方制剂可增加缺氧复氧后海马CAI区GABA表达及防止Glu过度释放,对缺氧复氧性脑损伤具有保护作用。 相似文献
62.
Cotinine levels in follicular fluid and serum of IVF patients: effect on granulosa-luteal cell function in vitro 总被引:1,自引:0,他引:1
Cigarette smoking is accepted as a risk factor for pregnancybut its effect on fertility is uncertain. In this study we determinedthe concentration of cotinine, a nicotine metabolite, in follicularfluid and serum from women participating in an In-vitro fertilizationand embryo transfer (IVF-ET) programme. Cotinine was undetectableIn serum and follicular fluid of non-smokers but ranged from<5 to 371 ng/ml in follicular fluid and from 24 to 245 ng/mlin serum of smokers. Granulosa-luteal cells, obtained from IVFpatients and cultured for 4 days, secreted progesterone and,when an aromatizable androgen was added, oestradiol-17. Theaddition of cotinine or nicotine did not alter progesteroneor oestradlol-17 secretion. However, the presence of cotininein follicular fluid of women smokers provides evidence for accessof at least one component of cigarette smoke to the developinggamete and the cells of the follicle. Further work is requiredto determine whether fertllity is compromised by the presence,In follicular fluid, of contaminants derived from cigarettesmoke. 相似文献
63.
Matturri L Ottaviani G Lavezzi AM 《Virchows Archiv : an international journal of pathology》2005,447(1):74-80
Cigarette smoking is associated with an increased incidence of atherosclerotic diseases. The aim of this study was to examine the progression of the preatherosclerotic lesions previously observed by us in coronary arteries of fetuses of smoker mothers and in infants with smoker parents. We examined the coronary arteries of 34 infants, aged 1–36 months, and the histological and biological [c-fos, proliferating cell nuclear antigen (PCNA), and apoptosis] features of the early atherosclerotic lesions. In 17 infants (50%), at least one parent smoked, generally more than five cigarettes a day. In 18 cases (53%), we observed variable thickening of the coronary walls from preatherosclerotic lesions to juvenile atherosclerotic plaques, related to parental smoking habit. This morphological progression of the lesions was accompanied by a sequence of biological changes in the smooth muscle cells of the tunica media. We suggest that the oxidants present in the gas phase of the parental cigarette smoke pass through the endothelium and induce at first the c-fos gene activation and subsequently the PCNA positivity, that is, a proliferative process. 相似文献
64.
J.A. McLean J.R. Bacon K.P. Mathews J. Banas D. Capati N.K. Bayne 《The Journal of allergy and clinical immunology》1983,72(2):187-192
Preliminary experiments indicated that solutions of aspirin (ASA) in buffered saline, pH 7.35, did not significantly change nasal airways resistance (NAR) when 0.1 ml of solution containing 22.5 mg (or less) per deciliter was sprayed into each nostril. Subsequently it was shown that this quantity of ASA administered intranasally did not significantly change NAR responses 15 min later to intranasal administration of increasing concentrations of histamine, methacholine, or an irritant (NH3 gas). However, the same atopic subjects demonstrated significantly decreased responses to intranasal challenge with short ragweed extract (SRW) after intranasal ASA. In addition, prior oral administration of ASA, Na salicylate, and indomethacin significantly inhibited nasal challenge responses to SRW in sensitive subjects under controlled conditions. 相似文献
65.
银杏叶提取物联合盐酸文拉法辛对抑郁大鼠海马nNOS蛋白表达及NO水平的影响 总被引:17,自引:0,他引:17
目的 :探讨抑郁症脑损伤的机制 ,研究银杏叶提取物 (EGb)及合成抗抑郁药盐酸文拉法辛(Venlafaxine)对抑郁大鼠的抗脑损伤及神经元保护作用。方法 :慢性应激建立大鼠抑郁模型。将 84只雄性大鼠分为正常对照组、抑郁模型组和不同治疗组。快速断头法处死 ,取海马后一侧进行免疫组化反应 ,观察海马CA3区nNOS蛋白的表达 ;另一侧检测NO含量 ;同时测定血清中NO含量。结果 :抑郁模型组海马nNOS表达增加 ,海马及血清中NO含量增加 ,P <0 0 1;联合用药组海马nNOS表达下降 ,海马及血清中NO含量减少 ,P <0 0 1。结论 :慢性应激增加海马nNOS表达 ;EGb有减轻神经元损伤 ,保护神经元的作用 ,其与Venlafaxine合用可能会达到对抑郁进行多靶点、多层次的治疗 ,弥补单一用药的不足。 相似文献
66.
苦瓜提取物对实验性Ⅱ型糖尿病大鼠的血糖的影响 总被引:2,自引:0,他引:2
目的:观察苦瓜提取物对链脲霉素引起的Ⅱ型糖尿病大鼠模型的血糖、血清胰岛素及血脂的影响。方法:大鼠尾静脉注射小剂量链脲霉素25mg·kg-1,同时喂以高糖高脂饲料复制Ⅱ型糖尿病大鼠模型.然后给予苦瓜提取物14,28,56mg·kg-1,连续灌胃给药4周后,测定血糖、血清胰岛素及血脂。结果:苦瓜提取物14,28,56mg·kg-1能降低实验性Ⅱ型糖尿病大鼠血糖及血清胰岛素水平,能升高HDL-C含量,而对血脂其它指标无明显影响。结论:苦瓜提取物对Ⅱ型糖尿病大鼠有治疗作用。 相似文献
67.
目的:研究香烟烟雾提取物(CSE)对哮喘大鼠气道平滑肌细胞(ASMC)蛋白激酶C(PKC)活性的影响。 方法: 24只Wistar大鼠随机分为哮喘干预组(A组)、单纯哮喘组(B组)、对照干预组(C组)及对照组(D组),用5% 浓度的CSE干预A、C两组ASMC,分别于干预0、1、2、3和6 h后,分离ASMC,提取胞浆及胞膜PKC,然后用[γ-32P]-ATP催化活性测定法检测PKC的活性。结果:(1)ASMC胞膜、胞浆PKC活性及两者比值:在1 h及2 h时,A组显著强于B、C、D组(均P<0.01);B、C组显著强于D组(P<0.01,P<0.05);B组与C组在1 h、2 h时均无显著差异。而B组与C组在1 h、2 h时差异均无显著(P>0.05)。(2)组内ASMC胞膜、胞浆PKC活性比值:A、B、C 3组:1 h显著高于0 h、2 h(均P<0.01);B组:2 h显著高于0 h(P<0.05)。 结论:CSE可能通过改变PKC的活性而进一步影响哮喘及其它呼吸系统疾病的发生、发展。 相似文献
68.
The effect of allogeneic and syngeneic extracts from the spleens of male and female inbred mice on primary cultures of fibroblasts obtained from the subcutaneous connective tissues of fetuses of CBA and C57BL/6J mice was studied. The cytotoxic and growth-inhibiting action on the cultures was successively enhanced by the use of extracts from syngeneic male and allogeneic female and male tissues. Consequently, an increase in the degree of antigenic difference between the target cells and extracts led to enhancement of the phenomenon of allogeneic inhibition. It was shown for the first time that in a syngeneic system extracts from male tissues (containing the weak H-Y antigen) have a cytotoxic action on cells from female inbred mice, i.e., that they induce a reaction of the allogeneic inhibition type.Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi biologii i meditsiny, Vol. 86, No. 10, pp. 486–488, October, 1978. 相似文献
69.
Ilhan Kaya Nazife Yigit Mehlika Benli 《African journal of traditional, complementary, and alternative medicines》2008,5(4):363-369
The antimicrobial activities of chloroform, acetone and two different concentrations of methanol extracts of Ocimum basilicum L. were studied. These extracts were tested in vitro against 10 bacteria and 4 yeasts strains by the disc diffusion method. The results indicated that the methanol extracts of O. basilucum exhibited the antimicrobial activity against tested microorganisms. While the chloroform and acetone extracts had no effect, the methanol extracts showed inhibition zones against strains of Pseudomonas aeruginosa, Shigella sp., Listeria monocytogenes, Staphylococcus aureus and two different strains of Escherichia coli. The cells of microorganisms, which were treated and untreated with plant extracts, were observed by using the scanning electron microscope. It was observed that the treated cells were damaged. 相似文献
70.
Immunologic events in pigeon breeders'' disease 总被引:8,自引:0,他引:8
Vernon L. Moore Ph.D. Jordan N. Fink M.D. Joseph J. Barboriak Sc.D. Louis L. Ruff M.D. Donald P. Schlueter M.D. 《The Journal of allergy and clinical immunology》1974,53(6):319-328
The immunologic and physiologic status of a group of symptomatic and asymptomatic pigeon breeders was studied in an attempt to define the immunologic events occurring in pigeon breeders' disease. Antibody activity to antigen(s) present in pigeon dropping extract (PDE) and pigeon serum (PS) was detected in the serum of both symptomatic and asymptomatic breeders. Antibody activity, however, tended to be greater in the symptomatic pigeon breeders. When subjects were challenged with PS via aerosol, serum complement activity became depressed only in asymptomatic patients. Cellular hypersensitivity to antigens present in PDE was detected in vitro in peripheral lymphocyte populations of 4 of 5 symptomatic breeders and in none of the asymptomatic breeders; cellular hypersensitivity to antigens in PS was not demonstrated in any of the individuals tested. These findings indicate that cell-mediated hypersensitivity, as well as humoral immunologic processes, may be involved in the pathogenesis of the hypersensitivity pneumonitis found in pigeon breeders. 相似文献