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41.
一些保肝药物对原代培养大鼠肝细胞糖原合成功能的影响 总被引:1,自引:0,他引:1
本文参照PO Seglen的方法并加以修改,建立了原代培养大鼠肝细胞糖原合成功能的测定体系。观察到联苯双酯既能使正常肝细胞合成糖原增加88%,又能保护肝细胞完全拮抗四氯化碳对其功能的损伤;银耳多糖能使四氯化碳对肝细胞糖原合成功能的损伤减轻57%;去甲斑蝥素10μg/ml能增加肝细胞糖原合成,浓度增加到100μg/ml时,此作用减弱,1000μg/ml则明显抑制糖原的合成,而且在10~100μg/ml浓度时,即能加强四氯化碳的损伤作用;100μg/ml CL1500和熊果酸二钠单独应用可增加肝细胞糖原合成,但与四氯化碳同时应用,反而加重对糖原合成的抑制作用。 相似文献
42.
43.
Tyrosine hydroxylase and serotonin containing cells in embryonic rat rhombencephalon: a whole-mount immunocytochemical study 总被引:5,自引:0,他引:5
Rhombencephala from rat embryos were processed as whole-mounts for immunocytochemical detection of monoaminergic cell populations, using antibodies to tyrosine hydroxylase (TH) and serotonin (5-HT). Specific advantages of the whole-mount technique over the classical serial-section method were that even isolated immunoreactive (IR) cells could be detected easily, and three-dimensional relationships could be ascertained without the need for serial reconstruction. Embryos between embryonic days (E) 12 and 16 (the day following nocturnal mating being considered as E1) were used in this study. Both TH and 5-HT immunoreactivities were already detectable at E12, even in the smallest embryos (crown-rump length: 6 mm), but there was a striking difference in the number and regional distribution of these two types of IR cells. TH was expressed in several cell groups located in the rostral rhombencephalon (the presumed anlage of the A4-7 complex) as well as in the caudal rhombencephalon (the presumed anlagen of groups A1-2 and C1-3), whereas 5-HT was expressed in very few cells located near the rostral border of the rhombencephalon (presumed anlage of the B4-9 complex). Although the three-dimensional distribution of the TH-IR cell groups underwent some modifications during the period studied, its general pattern remained relatively stable after E12. This contrasted with the sequential appearance of the 5-HT-IR cell groups and their spatial transformations during this period. Using the rhombencephalic isthmus as a landmark, we found that conspicuous 5-HT-IR fibre bundles penetrated into the mesencephalon from E13 onwards, but that the 5-HT IR cell bodies were exclusively located caudal to the borderline between the mesencephalon and the rhombencephalon (the rhombencephalic isthmus). We therefore suggest the term "rostral rhombencephalic raphe nuclei" for the rostral 5-HT cell groups instead of "mesencephalic raphe nuclei," which is a misnomer. Close spatial association between TH and 5-HT-IR elements was observed mainly in the caudal rhombencephalon, where 5-HT-IR fibres coursed through an area containing numerous TH-IR cell bodies (the presumed anlagen of groups A1-2 and C1-3). 相似文献
44.
补益中药有效活性成分的免疫药理研究及应用 总被引:4,自引:0,他引:4
几种补益中药(枸杞子、淫羊藿、黄芪和女贞子)的多糖成分具有免疫增强和调节作用,这种作用以提高T淋巴细胞功能为主.主要包括:(1)对有丝分裂剂诱导的T细胞增殖反应更敏感;(2)提高细胞免疫功能的作用部位在胸腺;(3)对于免疫功能低下的老龄鼠和荷瘤鼠均有明显增强T淋巴细胞活性作用.补益中药的多糖成分可能是它们具有"扶正固本"和调节免疫功能的主要物质基础. 相似文献
45.
The connectivity of a region surrounding the established thalamic auditory nuclei, n. ovoidalis (Ov) and n. semilunaris parovoidalis (SPO), was explored in the ring dove by using the anterograde tracers, Phaseolus vulgaris leucoagglutinin (PHAL) and biocytin, and the retrograde tracer, fluorogold. The Ov-SPO surround received a projection from a cell group along the interface of the auditory midbrain and the n. intercollicularis, as revealed with PHAL and biocytin, and was composed of neurons exhibiting a common morphology. These features and the presence of overlapping projections from different portions of the Ov-SPO surround suggest that this region comprises a functionally discrete area, which we term the Ov shell. Single unit recording within the shell established the existence of acoustically responsive units. Both PHAL and fluorogold labeling revealed a robust projection from the Ov shell to the caudomedial hypothalamus. Major telencephalic projections of the shell terminated within the ventral paleostriatal complex, "end-zones" of the field L, the caudomedial hyperstriatum ventrale, and regions immediately dorsal and lateral to the auditory neostriatum. Except for a portion of the shell bordering medial ovoidalis, PHAL injections into the shell also labeled fibers within the caudolateral neostriatum and along the lateral neostriatal rim. The connectivity of the Ov shell suggests that this region may integrate auditory pathways with brain regions associated with endocrine mediated behavior. In addition, the shell may constitute a source of converging input to several levels of central auditory pathways. 相似文献
46.
目的:探讨细胞外基质纤维连接蛋白(FN)、层黏连蛋白(LN)及三维基膜Matrigel胶对平滑肌细胞黏着斑激酶(FAK)表达的影响。方法:免疫荧光组织化学技术对生长在FN、LN和Matrigel胶里的平滑肌细胞FAK的表达进行检测。结果:生长存FN、LN和Matrigel胶里的平滑肌细胞FAK的表达依次为最高、次之和最低,各组之间有统计学意义;平滑肌细胞FAK磷酸化水平和FAK的表达呈正相关,生长在FN上的平滑肌细胞FAK(py397)的表达水平最高,生长在Matrigel胶里的平滑肌表达最低。结论:细胞外基质成分及其构筑对平滑肌细胞FAK的表达具有重要调节作用。 相似文献
47.
Bonnie B. Punske Wayne E. Cascio Connie Engle H. Troy Nagle Leonard S. Gettes Timothy A. Johnson 《Annals of biomedical engineering》1998,26(6):1010-1021
This study applied zero-delay wave number spectral estimation as a means of quantifying the changes in activation and recovery sequences of propagating plane waves on the epicardial surface of in situ porcine hearts during regional hyperkalemia and ischemia. Unipolar electrograms (104) were recorded from the left ventricular surface of nine hearts using a plaque electrode array with 1 mm spatial sampling intervals. The objectives were (1) to define a set of parameters capable of quantifying the spatial and temporal changes in measured extracellular potentials associated with localized ischemia prior to the onset of conduction block; (2) to elevate regional levels of extracellular potassium ion concentration and quantify potential changes due to this known physiologic manipulation; and (3) to use quantitative parameters to make statistical comparisons in order to distinguish wave fronts during normal, ischemic and hyperkalemic conditions. Results showed that the parameters of wave number and average temporal frequency and the associated power, as determined from the wave number spectrum, provided statistically significant (p < 0.05) quantification of changes in wave front features during normal and ischemic or hyperkalemic conditions. The results were consistent with results obtained from conventional time–space domain methods like isochronal mapping and electrograms, with the advantage of a quantitative result enabling simple comparisons and trend analysis for large numbers of heart beats. © 1998 Biomedical Engineering Society.
PAC98: 8759Wc, 8722Fy, 8780+s 相似文献
48.
Tamkovich SN Laktionov PP Rykova EY Starikov AV Skvortsova TE Kuznetsova NP Permyakova VI Vlasov VV 《Bulletin of experimental biology and medicine》2005,139(4):465-467
The concentrations of extracellular DNA and RNA were measured in the plasma of donors and patients with fibroadenoma and breast cancer. The content of extracellular DNA surpassed the normal in 80% plasma samples from patients with mammary tumors. Extracellular RNA was detected in 30% plasma samples from donors and patients with breast tumors. No correlations were found between plasma concentration of extracellular DNA and size and stage of tumor growth. Hence, measurement of extracellular DNA in the plasma of patients can be used only as an accessory test for tumor diagnosis.__________Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 139, No. 4, pp. 462–464, April, 2005 相似文献
49.
Tezak Z Prandini P Boscaro M Marin A Devaney J Marino M Fanin M Trevisan CP Park J Tyson W Finkel R Garcia C Angelini C Hoffman EP Pegoraro E 《Human mutation》2003,21(2):103-111
Complete laminin alpha2 (LAMA2) deficiency causes approximately half of congenital muscular dystrophy (CMD) cases. Many loss-of-function mutations have been reported in these severe, neonatal-onset patients, but only single missense mutations have been found in milder CMD with partial laminin alpha2 deficiency. Here, we studied nine patients diagnosed with CMD who showed abnormal white-matter signal at brain MRI and partial deficiency of laminin alpha2 on immunofluorescence of muscle biopsy. We screened the entire 9.5 kb laminin alpha2 mRNA from patient muscle biopsy by direct capillary automated sequencing, single strand conformational polymorphism (SSCP), or denaturing high performance liquid chromatography (DHPLC) of overlapping RT-PCR products followed by direct sequencing of heteroduplexes. We identified laminin alpha2 sequence changes in six of nine CMD patients. Each of the gene changes identified, except one, was novel, including three missense changes and two splice-site mutations. The finding of partial laminin alpha2 deficiency by immunostaining is not specific for laminin alpha2 gene mutation carriers, with only two patients (22%) showing clear causative mutations, and an additional three patients (33%) showing possible mutations. The clinical presentation and disease progression was homogeneous in the laminin alpha2-mutation positive and negative CMD patients. 相似文献
50.
金针菇子实体多糖提取物对人肝癌SMMC—7721细胞的抑增殖作用 总被引:2,自引:0,他引:2
金针菇子实体经热水提取,乙醇沉淀,胰蛋白酶水解,Sevag法去除蛋白质,乙醇分级沉淀等处理得金针菇子实体多糖。研究了该多糖对人肝部SMMC-7721细胞生长曲线,有丝分裂指数及线粒体活性的影响。结果表明该多糖对体外培养的人肝癌SMMC-7721细胞具一定抑制作用。 相似文献