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101.
Jaroslav Salamoun Jo
rg Remien 《Journal of pharmaceutical and biomedical analysis》1992,10(10-12):931-936
The inhibiting compounds were separated by micro-column liquid chromatography in the mobile phase containing the natural substrate acetylcholine. A home-made packed bed microbioreactor system containing immobilized enzyme acetylcholinesterase (ACHE) in human red blood cell membrane and choline oxidase (CHO) from alcaligenes was used for the post-column conversion of acetylcholine to hydrogen peroxide which was detected by an electrochemical detector. The inhibition effect of the solutes caused a decrease in the acetylcholinesterase activity, a decrease in the formation of hydrogen peroxide and also a decrease in the response corresponding to the concentration of the solutes. The rate of the enzyme regeneration was also recorded. The micro-system was compared with a conventional LC system comprising commercially prepared enzyme reactor. The stability of the enzymes is at least 3 weeks at ambient temperature. The limit of detection depends on biological activity of inhibition and for galanthamine was 1 pmol. 相似文献
102.
Based upon detailed dissections of the lymphatic system in adult cadavers, the lymphatic drainage of the gallbladder was divided
into three pathways: (1) The cholecystoretropancreatic pathway, which had two routes, one running spirally from the anterior
surface of the common bile duct to the right rear, and the other running almost straight down from the posterior surface of
the common bile duct. These routes converged at the principal retroportal node at the posterior surface of the head of the
pancreas. (2) The cholecysto-celiac pathway; this was the route running to the left through the hepatoduodenal ligament to
reach the celiac nodes. (3) The cholecysto-mesenteric pathway; this was the route running to the left in front of the portal
vein to connect with the nodes at the superior mesenteric root. The cholecysto-retropancreatic pathway can be regarded as
the main pathway, and the principal retroportal node appeared to be critical as the main terminal node in the visceral lymphatic
system of the gallbladder. These three pathways converged with the abdomino-aortic lymph nodes near the left renal vein, and
the nodes in the interaortico-caval space were considered to be of particular importance.
Offprint requests to: M. Ito 相似文献
103.
Kohei SHIOTA 《Congenital anomalies》1991,31(2):67-80
Using the data from the Kyoto Collection of Human Embryos, three main topics related to normal and abnormal development of human embryos are discussed. 1) Wide variability was noted in developmental stage of human embryos at any given gestational age. This was true not only for the estimated ovulation age but also for ‘coital’ age in single coital cases. Such diversity in human prenatal development may be, at least in part, ‘normal’ biological variability and it should be taken into account when assessing the teratogenic risk of environmental agents to human embryos. 2) At the early postimplantation period prior to major organogenesis, the percentage of morphologically abnormal embryos is high (> 30%), which supports the clinical finding that a substantially large proportion of human conceptuses are eliminated at an early stage of pregnancy, often without the knowledge of the mother. The fate of undifferentiated abnormal embryos is not certain and should be studied. 3) Life-table estimates for normal and abnormal human conceptuses showed that more than 10% of all embryos recognizable at 5 weeks gestation are malformed or ‘potentially’ malformed. Because of selective intrauterine death of malformed embryos and fetuses, the proportion of the malformed drops to 2.4% by age 8 weeks and 1% at term. The cumulative intrauterine mortality rate of malformed conceptuses was estimated to be 93%, while the corresponding rate for normal conceptuses was 18%. 相似文献
104.
Antibody-dependent neutrophil-mediated parasite killing in non-lethal rodent malaria 总被引:1,自引:1,他引:0
S. WAKI 《Parasite immunology》1994,16(11):587-591
The effects of administrating recombinant human granulocyte colony-stimulating factor (rhG-CSF) and passively transferring immune serum on infection with an attenuated variant of Plasmodium berghei XAT (Pb XAT), in severe combined immunodeficiency (SCID) mice were examined. In immune competent (C.B-17) mice, the attenuated parasite infection was inevitably self-resolving and degenerating forms inside erythrocytes appeared, coinciding with the drop in parasitaemia, whereas SCID mice were unable to control parasite growth and all the mice died. Continuous administration with rhG-CSF caused neutrophilic granulocytosis in both SCID and C.B-17 mice. The effect of rhG-CSF on the infection in C.B-17 mice was to suppress the course of the parasitaemia at an early phase whereas it had no effect in SCID mice. When immune serum was transferred on the day of infection, the prepatent period was prolonged two days in both SCID and C.B-17 mice. When administration with rhG-CSF was combined with transfer of immune serum, SCID mice showed four days delay in patency and degenerating parasites were seen during the course of parasitaemia, although the infection was ultimately fatal. C.B-17 mice similarly treated showed a seven day delay in the onset of the patent parasitaemia which was of a lesser magnitude and shorter in duration compared with control mice. On the other hand, when C.B-17 mice were splenectomized three weeks before infection and then treated with rhG-CSF and immune serum, no degenerating parasites were seen during the infection and all mice died with high parasitaemias. These results show that antibody-dependent neutrophil-mediated parasite killing may occur in the spleen of mice infected with P. berghei XAT. 相似文献
105.
Multiplex PCR analysis of in vivo-arising deletion mutations in the hprt gene of human T-lymphocytes
James C. Fuscoe Lisa J. Zimmerman Karen Harrington-Brock Martha M. Moore 《Environmental and molecular mutagenesis》1994,23(2):89-95
A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc. 相似文献
106.
用聚焦层析结合DEAE-Sephadex A-50离子交换层析,从正常人肝浸液中分离得两个精氨酸酶同工酶组分.经聚丙烯酰胺凝胶电泳(PAGE)鉴定从聚焦层析得到的第一峰同工酶组分为一条蛋白带,第二峰具有精氨酸酶活性的蛋白组分的主要蛋白带也极明显。各蛋白质成分向阴极电泳的前后顺序与从聚焦层析洗脱的先后次序一致。两型同工酶的比活力分别约为2050U/mg及790U/mg。用SDS-PAGE检测两型同工酶均由两种亚基组成,且分子量近似。 相似文献
107.
Corinna S. Bowser Jean Kaye Rauno O. Joks Cascy-Arnoux Charlot H. Jack Moallem 《Pediatric allergy and immunology》2007,18(4):298-303
Elevated serum immunoglobulin E (IgE) and increased prevalence of atopy is reported in patients infected with human immunodeficiency virus (HIV). The elevated serum IgE may be attributed to polyclonal stimulation of B cells or IgE production against allergens, viruses, fungi and bacteria. This study investigates the prevalence of atopy in perinatally HIV-infected children, and the relationships between serum IgE (and other serum immunoglobulins) with atopy, CD4+ cell count and HIV-disease stage. Serum immunoglobulin levels, epicutaneous skin test for common aeroallergens, clinical Centers for Disease Control and Prevention (CDC) classification, CD4+ cell counts and allergy history were extracted from the charts of perinatally HIV-infected children on highly active antiretroviral therapy. The prevalence of atopy (52%) and the pattern of aeroallergen sensitivity were comparable with the US pediatric population. Serum IgE levels did not correlate with clinical disease stage. However, in non-atopic patients, serum IgE levels increased with disease progression (p = 0.02). There was an inverse relationship between the prevalence of elevated serum IgE levels and atopy with progression of disease (p = 0.019). Serum IgE did not correlate with atopy, CD4+ cell count, or duration of HIV infection or levels of serum immunoglobulins. This is the first study to show no increased prevalence of atopy in perinatally HIV-infected children compared with the general population. In advanced stages of HIV, elevated serum IgE may be specific for antigens other than those known as allergens. 相似文献
108.
垂体高度的断层解剖及MRI测量 总被引:3,自引:0,他引:3
目的:通过尸体断层标本和MRI对照测量垂体的高度,为垂体的影像学诊断提供诊断标准、材料和方法:利用35例成人尸体断层标本,在各个断面上测量垂体的高度;在103例成人冠状头颅MRI上测量垂体的高度,并按年龄和性别分为十二组。将断层标本和MRI的测量数据进行比较。结果:在断层标本上测量垂体的平均高度为5.3±0.6(4.0-7.6)mm;MRI上的平均高度为5.4±1.3(4.0-8.3)mm。两组数据比较,无显著性差异(P>0.05)。男性垂体的平均高度为5.3±1.2(4.0-7.2)mm,女性垂体的平均高度为5.5±1.4(4.0-8.3)mm。女性垂体的平均高度大于男性。各年龄组比较显示,20岁以后,随年龄增长,垂体高度逐渐下降。结论:在MRI诊断中,垂体高度女性≥9mm,男性≥8mm可考虑垂体异常。垂体高度女性大于男性;20岁以后,随年龄增长,垂体高度有逐渐下降的趋势。 相似文献
109.
T. Yoshimaru Y. Suzuki T. Matsui† K. Yamashita† T. Ochiai‡ M. Yamaki† K. Shimizu 《Clinical and experimental allergy》2002,32(4):612-618
BACKGROUND: Previous studies have shown that rat peritoneal mast cells and mast cell model rat basophilic leukaemia (RBL-2H3) cells generate intracellular reactive oxygen species (ROS) in response to antigen challenge. However, the physiological significance of the burst of ROS is poorly understood. OBJECTIVE: The present study was undertaken to investigate the role of superoxide anion in mediator release in rat and human cell systems. METHODS: RBL-2H3 cells were directly stimulated with anti-rat FcepsilonRI alpha-subunit monoclonal antibody (mAb). For the analysis of human cell system, leucocytes were isolated by dextran sedimentation from healthy volunteers or from patients, and challenged either with anti-human FcepsilonRI mAb or with the relevant antigens. Superoxide generation was determined by chemiluminescence-based methods. The releases of histamine and leukotrienes (LT)s were determined by enzyme-linked immunosorben assay (ELISA). RESULTS: Cross-linking of FcepsilonRI on RBL-2H3 cells or on human leucocytes from healthy donors by the anti-FcepsilonRI mAb resulted in a rapid generation of superoxide anion, as determined by chemiluminescence using superoxide-specific probes. Similarly, leucocytes from patients generated superoxide anion in response to the challenge with the relevant allergen but not with the irrelevant allergen. Furthermore, diphenyleneiodonium (DPI), a well-known inhibitor of flavoenzymes suppressed the superoxide generation and the release of histamine and LTC4 induced by the anti-FcepsilonRI mAb or by allergen in parallel. CONCLUSION: These results indicate that both RBL-2H3 cells and human basophils generate superoxide anion upon FcepsilonRI cross-linking either by antibody or by allergen challenge and that blockade of the generation prevents the release of allergic mediators. The findings strongly support the role of superoxide generation in the activation of mast cells and basophils under both physiological and pathological conditions. The findings suggest that drugs regulating the superoxide generation have potential therapeutic use for allergic disorders. 相似文献
110.
目的:观察思他宁对人胰腺癌细胞ASPC-1的生长作用.方法:细胞培养,分别加入不同浓度的思他宁.应用MTT法来观察细胞增殖程度;放免法测定细胞内cAMP含量;荧光法测定[Ca2 ]i.结果:不同浓度的思他宁(10-11~10-6mol/L)均能有效地抑制ASPC-1的生长,能抑制ASPC-1细胞内cAMP生成和细胞内钙离子水平,cAMP生成量和细胞内钙离子水平与思他宁浓度呈负相关.结论:思他宁能抑制ASPC-1细胞的生长,经过特异性受体调节. 相似文献