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991.
992.
Yukichi Tanaka 《Virchows Archiv : an international journal of pathology》1987,410(2):125-132
Summary The present study concerns the immunocytochemical localization of S-100 protein and subunits in the cells of human lymphoreticular tissue and their related tumours. The subunit is mainly localized in dendritic cells, most likely the dendritic reticulum cells (DRCs) located within the germinal centers, while the subunit is mainly localized in the interdigitating reticulum cells (IRCs) in the paracortical area and in Histiocytosis X cells. No immunoreactivity for either subunit was found in the majority of normal lymphocytes, macrophages, malignant lymphoma cells, or xanthoma cells.The DRCs and IRCs are generally considered to show different distribution in the lymphoid tissues and demonstrate some difference in their immunocytochemical and enzyme-histochemical features. It is suggested that S-100 subunits can be used as useful markers for these two types of dendritic cells and investigation of these subunits may provide more information for the study of human lymphoreticular system. 相似文献
993.
Calbindin (CALB), a calcium-binding protein, is known to be expressed in the embryonic nervous system. In this study, we have examined its distribution in the cerebellum of human fetuses (11–25 weeks of gestation) and adult by immunohistochemistry. At the gestational age of 11–12 weeks, CALB immunoreactivity was present in granule and Purkinje cells throughout the cerebellum. By 16–21 weeks of gestation, immunoreactive Purkinje cells were well-differentiated in the vermis and flocculus, and their axons ran towards the deep cerebellar nuclei area, while the axon collaterals were seen to be distributed into adjacent folia. At the gestational period of 24–25 weeks, most Purkinje cells of the flocculus and vermis were arranged in one to two rows, while those of the hemispheres were still undifferentiated. A few Golgi cells of the vermis showed immunoreactivity. The neurons of the deep nuclei were immunonegative right from the gestational age of 11 weeks although a fine stippled staining of fibers was present throughout the body of all nuclei. The fibers lying close to the hilum of the dentate nucleus were strongly CALB-positive. The vestibulocerebellar fibers, being traced at the level of lower pons and upper medulla oblongata were stained as early as 11 weeks of gestation, whereas the olivocerebellar fibers were stained from 16 weeks onward. In the adult cerebellum, Purkinje cells were moderately immunopositive while granule cells were faintly stained; no other cells, including those of the deep nuclei were stained. In the medulla oblongata, the inferior olivary nucleus and olivocerebellar fibers were strongly CALB-positive. Our results indicate that CALB is expressed in early migratory Purkinje cells, and their maturation occurs in a vermal-to-hemisphere gradient. It is likely that CALB plays a significant role in the regulation of Ca2+-dependent activities in the developing cerebellum. 相似文献
994.
Vlad Vasiliu Peter Herzer Dieter Rössler Gisela Lehnert B. Wilske 《Medical microbiology and immunology》1998,187(2):97-102
Borrelia burgdorferi sensu lato, the etiological agent of Lyme borreliosis, has been divided into three genospecies: B. burgdorferi sensu stricto (OspA-type 1), B. afzelii (OspA-type 2) and B. garinii (OspA-type 3–7). Whereas in Europe B. afzelii (OspA-type 2) is predominant among human skin isolates and B. garinii (OspA-type 3–7) among human CSF isolates, some previous serological studies suggested that Lyme arthritis is also associated
with B. burgdorferi sensu stricto in Europe. In the present study we designed ospA type-specific PCRs and identified four different ospA types associated with Lyme arthritis. Our study group consisted of 20 patients with positive serology (ELISA and immunoblotting)
and clinical criteria for Lyme arthritis. B. burgdorferi DNA was detected in 13 patients and in none of 10 control patients from synovial fluid. We identified ospA-type 1 (26.6%), ospA-type 2 (33.3%), ospA-type 4 (6.6%) and ospA-type 5 (33.3%). Our conclusion is that in Europe B. burgdorferi sensu lato strains causing Lyme arthritis are considerably heterogeneous and that there is no prevalence of certain genospecies
or OspA-types among this strains.
Received: 14 May 1998 相似文献
995.
Kritaya Kongsuwan Michael A. Johnson Christopher T. Prideaux Michael Sheppard 《Virus genes》1993,7(3):297-303
To localize the gene encoding the 60 kD glycoprotein (gp60) of infectious laryngotracheitis virus (ILTV), a library of the ILTV genome was constructed in the gt11 expression vector. Twelve recombinant bacteriophages expressing gp60 epitopes as fusion products with -galactosidase were detected by immunoscreening with monoclonal antibodies specific for gp60. The ILTV DNA sequence contained in one of these recombinants 24-4 was used as a hybridization probe for mapping the insert sequence on the viral genome. The gene for the gp60 was located at map unit 0.72–0.77 in the unique long region (UL) of the ILTV genome. The DNA sequence of the 1.2 kb insert of 24-4 containing the gp60 epitope was determined. The majority of deduced gp60 amino acid sequence has no homology with any of the known alphaherpesvirus glycoproteins.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession number X 121209. 相似文献
996.
Neuropeptide Y (NPY) has at least three receptors (Y1, Y2 and Y3) through which it influences different mechanisms in many cell types. Previous data suggest that the Y2 receptor may be divided into prejunctional and postjunctional subgroups. We have examined the intracellular signalling pathways of the postjunctional Y2 receptor in rat renal proximal tubules. The results indicate that NPY regulates Na+,K+-ATPase through several signalling pathways: (1) In proximal tubule (PT) cells NPY increased intracellular calcium. The response was blocked by removing extracellular calcium and was also blocked by using nifedipine. This suggests that calcium was increased by influx from the extracellular space through L -type calcium channels. (2) NPY increased Na+,K+-ATPase activity in PT segments and this effect was also blocked by nifedipine. CaMKII-Ala286[281–302] a blocker of Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibited the NPY-stimulated Na+,K+-ATPase activity. This implies that increased intracellular calcium activates CaMKII which subsequently increases Na+,K+-ATPase activity. CaMKII thus appear to act similar to what has been proposed for protein phosphatase 2B. (3) Calphostin C, an inhibitor of protein kinase C (PKC), did not inhibit NPY-stimulated Na+,K+-ATPase activity. PKC is, therefore, unlikely to be involved. (4) Y2 receptors are negatively coupled to the cAMP pathway. NPY attenuated forskolin-stimulated cAMP production in renal tubules and exogenous cAMP counteracted the NPY-stimulated Na+,K+-ATPase activity. This illustrated the importance of NPY for the regulation of renal sodium handling. We also propose that the renal tubule cell is a good model for studying the function and mechanisms of postjunctional Y2 receptors. 相似文献
997.
The measurement of CA 125 and placental protein 14 in uterine flushings in women with recurrent miscarriage; relation to endometrial morphology 总被引:2,自引:2,他引:2
Dalton C.F.; Laird S.M.; Serle E.; Saravelos H.; Warren M.A.; Li T.C.; Bolton A.E. 《Human reproduction (Oxford, England)》1995,10(10):2680-2684
The concentrations of CA 125 and placental protein 14 (PP14)were measured in uterine flushings obtained throughout the lutealphase of the cycle from eight normal fertile women. The concentrationsof both proteins increased in a similar pattern throughout theluteal phase of the cycle, with the most dramatic increase occurring6 days after their luteinizing hormone surge (day LH +6). However,a greater variation in CA 125 concentrations was seen comparedto that seen for PP14. The concentrations were compared to thoseobtained on day LH + 7 of the cycle from a group (n equals;35) of women with recurrent miscarriage. The ranges in concentrationof PP14 and CA 125 in the flushings of fertile and recurrentmiscarriage patients were very similar. However, a greater proportionof women with recurrent miscarriage (55%) had low concentrations(<5 ng/ml) of PP14 than in the control group (12.5%) andthe concentrations of PP14 in the uterine flushings were significantlyless (P < 0.05) in women with recurrent miscarriage comparedto the normal fertile group. There was no significant differencein the concentrationof CA 125 in the uterine flushings betweenthe two groups. Histological observation of the endometrialbiopsy samples from recurrent miscarriage patients gave menstrualcycle datings that ranged from day LH +2.5 to LH +6.5 with retardedendometrium (;day LH +5) in 12 of 35 (34%) patients. Of these12 patients, 10 (83%) had low PP14 concentrations and six (50%)had low CA 125 concentrations in their uterine flushings. Inthe recurrent miscarriage patients with histologically normal(sequals; day LH +5) endometrial development, 10 out of 23 (43%)also had low PP14 concentrations and 8 out of 23 (35%) had lowCA 125 in their uterine flushings. The results suggest thatPP14 is better than CA 125 as a marker for endometrial functionin this group of women. In some cases (52%) the low concentrationsof PP14 in the uterine flushings couldbe explained by retardedendometrial development but for the others the reduction inPP14 concentration in the uterine flushing was not associatedwith retardation of endometrial development. 相似文献
998.
Kiyoshi Tanabayashi Kaoru Takeuchi Michiko Hishiyama Akio Yamada Akira Sugiura 《Virus genes》1990,3(4):361-365
The nucleotide sequence of the gene encoding the matrix (M) protein of mumps virus (MuV), Miyahara strain, has been determined from several overlapping cDNA clones. The M protein mRNA is 1248 nucleotides in length, exclusive of the poly(A) tail, and codes for a protein of 375 amino acids (Mr41,556). Comparison of the deduced amino acid sequence of the M protein of the Miyahara strain with that of the SBL-1 strain revealed that the M proteins of both strains are highly conserved. A significantly lower rate of nucleotide differences conducive to amino acid differences in the M gene compared with other genes appeared to indicate the importance of the conserved primary structure of the M protein for its function.Requests for reprints should be addressed to Kiyoshi Tanabayashi, Department of Measles Virus, National Institute of Health, 4-7-1 Gakuen, Musashimurayama, Tokyo 190-12, Japan. 相似文献
999.
我国福建汉族人HSP70基因多态性分析 总被引:1,自引:0,他引:1
目的了解福建省汉族人HSP70基因多态性分布,进而为探讨HSP70基因多态性与疾病的相关性提供遗传背景资料。方法应用聚合酶链反应技术、限制性内切酶分析检测了127名福建汉族正常人的HSP70基因3个多态性位点,并比较了部分不同地区和人群之间的基因型与等位基因频率。结果福建汉族人HSP70-1基因型(GG,GC和CC)分布频率分别是55.1%、40.2%和4.7%;HSP70-2基因型(从,AG和GG)分布频率分别是44.1%、铝.8%和6.9%;HSP70-hom基因型(Tr,TC和CC)分布频率分别是59.8%、37.0%和3.2%;HSP70-1等位基因频率G和C分别是75.2%和24.8%;HSP70-2等位基因频率A和G分别是68.5%和31.5%;HSP70-hom等位基因频率T和C分别是78.3%和21.7%。福建汉族人HSP70-1的基因型分布和等位基因频率同日本、墨西哥人群比较差异无统计学意义,与美国和西班牙人比较,差异有统计学意义(P〈0.01)。福建汉族人HSP70-1的GG纯合型(55.1%)显著高于美国(42.6%)和西班牙(33.0%)人群;福建汉族人HSP70-2的基因型分布和等位基因频率与日本人比较差异无统计学意义,与墨西哥、美国和西班牙人群比较,差异有统计学意义(P〈0.05),福建汉族人HSP70-2的AA纯合型(44.1%)高于墨西哥(23.O%)、美国(38.8%)和西班牙(20.O%)人群;福建汉族人群的HSP70-hom基因型和等位基因频率分布同日本、墨西哥、美国和西班牙人群的基本一致,差异无统计学意义,福建汉族人群的HSP70基因型和等位基因频率分布同中国台湾汉族人基本一致,差异无统计学意义,与武汉地区汉族人某些位点存在差异。结论福建汉族人HSP70基因多态性分布不同于某些地区的人群,具有种族和地区差异。 相似文献
1000.
血管发生(angiogenesis)依赖多种促进血管发生因子和抑制血管发生因子之综合的交互作用所调控。血管内皮生长因子(VEGF)和Notch信号传递途径(Notch signaling pathway)参与此过程。之前研究已证明Notch信号传递途径在胚胎发育和肿瘤血管发生(tumour angiogenesis)中扮演重要的角色,而最近研究则发现在血管发育过程中Dll4-Notch信号传递途径扮演着前所未知的新角色,并阐明因Notch信号传递减少而引起血管缺陷之机制,从而揭示破坏肿瘤血管发生的新药物靶点。本文着重于介绍Notch信号传递途径的组成;Dll4-Notch在血管发生中的作用;以及Dll4-Notch对肿瘤治疗的意义。 相似文献