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排序方式: 共有1102条查询结果,搜索用时 15 毫秒
1.
Cesare Mondadori Conrad Gentsch Bastian Hengerer Thomas Ducret Jürgen Borkowski Amy Racine Renate Lederer Albert Haeusler 《Psychopharmacology》1992,109(4):383-389
Oral pretreatment with aldosterone or corticosterone blocked the memory-enhancing effects of the calcium antagonist nimodipine, the ACE inhibitor captopril, the NMDA blocker CGP 37 849, and the glycine antagonist strychnine in a passive-avoidance test in mice. The memory-disturbing effects of phenobarbitone, diazepam, CGP 37 849 and scopolamine were not influenced by the hormonal pretreatment. These findings could indicate the involvement of a steroid-sensitive mechanism in drug-induced improvement of memory. In the light of clinical observations showing elevated cortisol levels in Alzheimer patients, the results might also explain why only a limited number of these patients respond to therapy with memory enhancers. 相似文献
2.
甲型流流感病毒鼠肺适庆型75-39株治疗S37腹水型荷瘤小鼠,存活率达93.3%。体外实验观察流感病毒感染S37肿瘤细胞,到3天时S37细胞经胎盘蓝染色,100%的S37细胞死亡,而对照组肿瘤细胞染色率只有10%左右。 相似文献
3.
Yu. G. Plyashkevich G. G. Barsegyan S. Yu. Ponomarev V. P. Demushkin 《Bulletin of experimental biology and medicine》1989,107(5):674-676
Brain Research Institute, All-Union Mental Health Research Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR O. S. Adrianov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 5, pp. 586–587, May, 1989. 相似文献
4.
Genome types of adenovirus types 19 and 37 isolated from patients with conjunctivitis in Hiroshima City 总被引:2,自引:0,他引:2
A total of 74 strains out of 33 strains of adenovirus type 19 (Ad19) plus 103 strains of type 37 (Ad37) isolated from patients with conjunctivitis at two ophthalmology clinics in Hiroshima City during the period March 1983 to December 1986 were analyzed by eight DNA restriction endonucleases in comparison with their prototype strains. All 27 Ad19 isolates examined displayed identical DNA cleavage patterns with all enzymes used (HindIII, KpnI, PstI, XhoI, BamHI, SacI, EcoRI, and SmaI), but their cleavage patterns were different from those of the prototype except with HindIII. The genome type of these isolates was tentatively named Ad19a. Forty-seven Ad37 isolates examined were divided into three genome types. They were tentatively named Ad37p, Ad37a, and Ad37b: 16 isolates (Ad37p) displayed DNA cleavage patterns identical with those of the prototype with all eight enzymes described above. Thirty isolates (Ad37a) showed the same patterns as the prototype except with EcoRI. One isolate (Ad37b) showed the same patterns as the prototype except with SmaI. The most frequently isolated genome type during the period studied was Ad37a, but the change of the predominant genome type in yearly incidences was observed. 相似文献
5.
Transient aphasia with lithium toxicity 总被引:1,自引:0,他引:1
J M Krakower 《Psychosomatics》1978,19(1):25-26
A case of transient aphasia in a 48-year-old woman is described. The aphasia occurred when progressive renal insufficiency led to accumulation of lithium to toxic levels, and was associated with well-known clinical findings of lithium toxicity. 相似文献
6.
Nakabayashi T Sakata KM Sakata A Kong L Lau CA Letterio JJ Vela-Roch N Talal N Dang H 《Inflammation》2001,25(2):69-73
The TGF-1(–/–) mouse is a murine model for systemic autoimmune disease. The aim of this study is to elucidate the immunological mechanism that leads to multifocal tissue inflammation and autoantibody production in TGF-1(–/–) mice. Heart, lung, liver, and salivary gland from TGF-1(–/–) were assessed for CD154 expression by RT-PCR and immunohistochemistry. Compared to wild-type littermates, CD154 expression was elevated in all tissues studied. Furthermore, IL-12 mRNA was expressed in the salivary gland and heart of TGF-1(–/–) mice and not in wild-type littermates. This suggests that the CD154 pathway is activated in these tissues. This shows that TGF-1 regulates CD154 expression leading to spontaneous IL-12 production and autoimmunity. 相似文献
7.
During the past 7 years the "Berlin epidemic MRSA" has spread throughout whole Germany. SmaI macrorestriction patterns of this clonal group are rather stable as are the length polymorphisms at the 3' end of the coagulase gene and the x-region of spa. However, the dru region (direct repeat units) of mec-associated DNA exhibits a length polymorphism due to deletion of one or more direct repeat units. Five different subclones could be discriminated by dru region length polymorphism. Location of deletions and of a few point mutations allow a delineation of these subclones. 相似文献
8.
Naohiro Yano Masayuki Endoh Raita Naka Fumio Takemura Yasuo Nomoto Hideto Sakai 《Journal of clinical immunology》1996,16(1):71-79
Previously we reported disease-specific interaction between interferon- (IFN-) and interleukin-4 (IL-4) in patients with IgA nephropathy (IgAN), suggesting the existence of unusual T cell behavior in this disease. In the present study, we investigated characteristic synthesis of interferon- (IFN-) and expression of IFN- receptor (IFN-R) in the peripheral blood mononuclear cells (PBMC) from patients with IgAN and other chronic proliferative glomerulonephritis (PGN). Heparinized peripheral blood samples were obtained from 38 patients with chronic mesangial proliferative glomerulonephritis (CGN; including 24 with IgA nephropathy) and 20 healthy controls. PBMC were isolated by gradient centrifugation and fragments were cultured in Iscove's modified Dulbecco's medium (IMDM) supplemented with 10% fetal calf serum (FCS) for 72 hr. IFN- concentrations in supernatants were evaluated by the enzyme-linked immunosorbent assay (ELISA). Other parts of PBMC pellets were reacted with anti-human IFN-R monoclonal antibody and FITC-labeled anti-mouse second antibody for analysis of IFN-R expression on these cells by FACScan. The remaining PBMC were fractionated into CD4+ T cells, CD8+ T cells, B cells, NK, cells and macrophages using the MACS cell sorting system. The isolated cells were evaluated for IFN- or IFN-R mRNA expression by the semiquantitative RT-PCR method.In vitro IFN- synthesis was enhanced in patients with CGN, and NK cells were revealed to be responsible for such enhancement. On the other hand, the expression of IFN-R on macrophages was suppressed in CGN patients. These results suggest that impairment of regulation of the IFN- system might be involved in the development of CGN. 相似文献
9.
目的 通过已建立的小鼠睾丸体外培养系统,研究四种内分泌干扰物(Endocrine Disrupting Chemicals,EDCs)对男性内分泌系统的影响。 方法 将新生小鼠的睾丸组织在体外环境中培养24h,而后在培养基中分别加入浓度为0.1μM, 1μM, 10μM and 100μM的四种(DEHP、MEHP、NP、p, p’-DDE)内分泌干扰物并培养72h,同时设置对照组;培养结束后进行组织学观察,测定冻存培养基中睾酮和抑制素βB (INH-βB)的分泌水平,同时测定细胞色素P450侧链裂解酶(P450Scc)、3β-羟基类固醇脱氢酶(3β-HSD)、细胞色素P45017α-羟化酶(P450C17)和波形蛋白(vimentin)的基因表达情况。 结果 所有剂量组中睾酮的分泌水平均发生改变;P450Scc、3β-HSD、P450C17和INH-βB蛋白质的表达及mRNA水平均受到四种内分泌干扰物的影响(P<0.05);DEHP和MEHP降低了波形蛋白的mRNA水平(P<0.05),而NP和p, p’-DDE对波形蛋白没有显著影响(P>0.05)。 结论 本研究建立的体外培养新生小鼠睾丸模型中,所选的四种已知EDCs改变了两种睾丸激素水平,三种类固醇合成酶以及与支持细胞功能相关的波形蛋白的表达。 相似文献
10.
目的 建立啤酒中4种N-亚硝胺类化合物(N-亚硝基二甲胺、N-亚硝基二乙胺、N-亚硝基二丙胺、N-亚硝基二苯胺)的同位素稀释固相萃取-气相色谱串联质谱测定方法。 方法 样品经活性炭固相萃取小柱富集、二氯甲烷洗脱,洗脱液经氮吹浓缩定容后,采用INNOWAX毛细管色谱柱分离,多反应监测(MRM)模式检测,同位素稀释内标法定量。 结果 各物质在5 μg/L~200 μg/L范围内线性关系良好,相关系数均大于0.9995。方法的检出限为0.03-0.10 μg/L,定量限为0.10~0.33 μg/L。不同水平的加标回收率为72.1%~100.3%,相对标准偏差为1.5%~9.5%(n=6)。 结论 该方法操作简单,灵敏度和准确度高,适用于啤酒中4种N-亚硝胺类化合物的测定。 相似文献