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81.
目的:探讨Egr-1基因剔除对实验性胰腺炎小鼠胰腺组织中炎性相关因子表达的影响。 〖HTH〗方法:利用Egr-1基因剔除小鼠,采用大剂量雨蛙素诱导的实验性胰腺炎模型,观察Egr-1基因剔除后,胰腺组织水肿、MPO水平、血清淀粉酶水平、肺组织MPO水平的改变。并利用定量PCR的方法,检测胰腺组织中炎症相关因子组织因子(TF)、纤维蛋白溶酶原激活因子抑制因子(PAI-1)、单核细胞趋化吸引蛋白1(MCP-1)、Gro-1、IL-6和细胞间黏附分子-1(ICAM-1) mRNA的表达。 〖HTH〗结果:Egr-1基因剔除小鼠胰腺组织水肿明显轻于野生型,但组织MPO水平与血清淀粉酶与野生型组间相比无明显差异;肺组织MPO水平明显低于野生型。定量PCR检测结果表明, Egr-1基因剔除组,胰腺组织中TF、PAI-1,以及MCP-1、ICAM-1和IL-6 mRNA的表达,明显少于野生型组。 〖HTH〗结论:Egr-1基因剔除可明显减轻急性胰腺炎的严重程度,其作用可能通过减少胰腺组织中TF、PAI-1,以及MCP-1、ICAM-1和IL-6的表达而实现。 相似文献
82.
小鼠第一次卵裂周期中线粒体分布的变化 总被引:2,自引:0,他引:2
用线粒体专一性活体荧光染色剂罗丹明123显示小鼠受精卵在第一次卵裂周期中M的分布变化,雌原核和雄原核在汇合之前,M在细胞质中呈弥散状随机分布,两原核汇合后,M在核周围略显聚集,第一次卵裂后期,M沿纺锤体微管和2个子核周围集中,但在赤道区域内明显稀少,预示出细胞分裂面的定位,这说明细胞质分裂是收综环收缩和细胞结构调整共同作用的结果。2-细胞阶段,M在细胞核周围明显聚集。2-细胞胚受秋水仙素作用后,M 相似文献
83.
Kerstin Eberhardt MD PhD Britt-Marie Larsson Social worker Kerstin Nived Social worker 《Patient education and counseling》1993,20(2-3):93-100
We report the interaction of RA and psychological factors over 2 years in a group of 89 patients with newly established disease. Short-time outcome regarding physical features was fairly good. Disease activity decreased, and disability evaluated by HAQ remained at a low level. Psychological distress as measured by the depression and anxiety subscales of SCL 90 (Symptom Check List) was not very pronounced and not related to disease state factors. A slight decrease of anxiety was recorded after 2 years. A new adjustment test was applied. It contained 13 items focused mainly on negative illness effects such as loss of independence, feelings of guilt, and change of social and leisure time activities. Three factors (regret of lost life values, dysphoric mood, and acceptance) explained 48% of the variance of the 13 items. The validity of the test was acceptable. The patients' degree of adjustment changed slowly or not at all during the 2 years. 相似文献
84.
In genome scans of ankylosing spondylitis (AS), with the exception of the HLA loci, linkage has not been easy to replicate across studies. We applied the genome-search meta-analysis (GSMA) method to genome scans of AS and spondyloarthropathy (SpA) to assess evidence for linkage across studies. Three AS genome scans and one SpA scan including 430 families with 1,048 affected individuals were used. All four original genome scans mainly analyzed Caucasian families. Seven bins had both Psumrnk and Pord<0.05, suggesting these bins most likely contain AS-linked loci; bin 6.2, 6.1, 6.3, 16.3, 19.2, 17.1, and 16.4. The GSMA produced significant genome-wide evidence for linkage on chromosome 6p22.3–6p21.1 (Psumrnk=0.000003), including the HLA locus. In addition to the HLA-B27 locus, strong linkage evidence was found on chromosome 6p25.3–6p22.3 (Psumrnk=0.0013) and 6p21.1–6p15 (Psumrnk=0.043). In the GSMA of four genome scans including one SpA study, the bin 9.4 (9q21.32–9q33.1) was newly found for linkage (Psumrnk=0.043, Pord=0.013). This GSMA added the evidence of the HLA loci as the greatest susceptibility factor to AS and showed evidences of chromosome 6, 16q, 19, 17p, and 9q as non-HLA susceptibility loci. 相似文献
85.
1988年至1991年对收治的发病5日以内的肾综合征出血热(HFRS)病人应用姬鼠型HFRSV陈株及家鼠型HFRSVR22株,免疫猪所制备的特异性双价纯化免疫血清F(ab)2(称F(ab)2血清),治疗HFRS病人65例作为研究组,以44例作为对照组。治疗结果表明:①球结膜水肿渗出减轻,24小时出血减轻;②白细胞病毒抗原消失迅速;③研究组出院平均早9.1天;④在洽疗后2、4日,对照组的特异性免疫荧光IgM抗体明显高于研究组的。⑤其他实验室检测指标都以研究组为优。提纯后的免疫血清F(ab)2无抗体-介导反应,无副作用及过敏反应。它含有特异性中和抗体及其他免疫因子,可中和清除体内的病毒抗原,减轻病毒血症及毛细血管壁的损伤,阻断病情发展,促进病情恢复。 相似文献
86.
Kazuei Ito Jutaro Takahashi Yasuhisa Yasuda Masahiro Takahashi Kyoko Kawahata Taichi Goto 《American journal of reproductive immunology (New York, N.Y. : 1989)》1998,39(6):356-361
PROBLEM: Early pregnancy factor (EPF) has been detected in pregnant bovine serum, and its activity appeared from 24 to 48 hr after insemination. However, in bovine in vitro fertilization (IVF), an EPF-like substance(s) had been detected in the culture medium of fertilized ovum. Therefore, we think that EPF and EPF-like substance(s) are very important materials for the development of the embryo. In this study, we examined the development of the embryo when fertilized bovine ova were cultured with IVF culture medium supplemented with EPF-positive or -negative serum. METHOD OF STUDY: EPF activity of each serum (fetal calf serum [FCS], calf serum [CS], estrus bovine serum, and pregnant bovine serum) was assessed by the bovine-rosette inhibition test. The sera were supplemented in TCM-199 culture medium, and IVF bovine ova were cultured with the media for 6 or 7 days, respectively. The culture media of each group were evaluated for EPF activity by the bovine-rosette inhibition test 48 hr after IVF. The cleavage rate of each group was calculated at 48 hr, and 6 or 7 days after IVF. The culture medium of cumulus cells was also tested for EPF activity. RESULTS: Only the pregnant bovine sera were EPF positive. All the culture media 48 hr after IVF became EPF positive. Additionally, the culture medium of cumulus cells did not have EPF activity. There was no significant difference in the cleavage rate of the EPF-positive and - negative sera 48 hr after IVF. However, the cleavage rate of EPF-positive sera tended to be higher than the negative sera. In contrast, the blastocyst development rates of EPF-positive sera were significantly higher than those of the negative sera 6 to 7 days after IVF (P < 0.05). CONCLUSIONS: The data suggest that an EPF-like substance(s) may be secreted from the in vitro fertilized bovine ovum but not from the cumulus cell, and that the EPF in the pregnant serum may accelerate the development of the bovine embryo in IVF. 相似文献
87.
Jean Valmier Michel Simonneau Sylvie Boisseau 《Pflügers Archiv : European journal of physiology》1989,414(3):360-368
The electrophysiological properties of a subset of dorsal root ganglion (DRG) neurons microdissected from 12-day-old (E12) mouse embryos and acutely isolated were analyzed as soon as 3 after their isolation. Two classes of neurons were defined according to their mean diameter. The larger diameter class was examined in this study. They display uniform cytoskeletal properties with co-expression of vimentin and neurofilament triplet proteins. Patch-clamp methods also revealed a homogeneous and limited repertoire of ionic channels that included (1) a TTX-sensitive Na+ current whose properties are similar to that reported in mature mammalian neurons, and (2) two types of K+ currents that can be compared with the delayed rectifier (I
k
) and the transient (I
a) potassium currents found in other mammalian preparations. It may be possible to use this in vitro model to examine the development of new types of currents, such as Ca2+ currents during neuronal growth and differentiation. 相似文献
88.
Chiara Fenoglio Daniela Galimberti Laura Piccio Diego Scalabrini Paola Panina Cecilia Buonsanti Eliana Venturelli Carlo Lovati Gianluigi Forloni Claudio Mariani Nereo Bresolin Elio Scarpini 《Neuroscience letters》2007
Triggering Receptor Expressed on Myeloid cells (TREM)2 deficiency originates a genetic syndrome characterized by bone cysts and presenile dementia, named Nasu-Hakola disease (NHD). Early onset dementia and marked involvement of frontal regions are features characterizing both NHD and other kinds of neurodegenerative disorders, such as Frontotemporal Lobar Degeneration (FTLD), and, in some cases, Alzheimer's disease (AD). Three Single Nucleotide Polymorphisms (SNPs) in TREM2 coding region were screened by allelic discrimination in a population of probable AD patients as well as FTLD patients as compared with age-matched controls. In addition, mutation scanning of the coding region of TREM2 gene was carried out in 7 patients with early onset AD (EOAD), 16 FTLD, and 20 controls. None of the SNPs analyzed was present, either in patients or controls. Moreover, mutation scanning of the five exons of TREM2 failed to detect the presence of novel polymorphisms. These data demonstrate that TREM2 coding region is highly conserved, implying a crucial role of this receptor. Further studies, including a functional analysis, are certainly required to clarify the role of TREM2 in neurodegenerative processes. 相似文献
89.
Salvatore Battaglia Giuseppe Barbolini Annibale R. Botticelli 《Virchows Archiv : an international journal of pathology》1979,382(3):245-259
Summary This study was performed in order to elucidate some of the problems of incidence, morphology and natural history concerned with Stage A prostatic cancer or prostatic microcarcinoma (PMC).The prostates of 100 patients, treated by subtotal prostatectomy for benign prostatic hyperplasia (BPH), were studied by comparing both routine and step-section techniques. The incidence of PMC was 41% by the former and 86% by the latter technique. Assessment of the size of PMC, as measured by the sum of the two main diameters, resulted in three groups: A1, A2, A3. The last of these may represent a frankly malignant condition, judged by size and the histological appearance. Radical prostatectomy is strongly suggested as appropriate therapy for this group.Supported in part by a Grant from the Ministry of Education (art. 286 T.U., 1977/78) 相似文献
90.
Dr. W. Hofmann Th. Rommel Th. Schaupp F. Seuter J. A. Rossner F. M. Hecht G. Mall 《Virchows Archiv : an international journal of pathology》1980,385(2):151-168
Zusammenfassung In unserer ultrastrukturell durchgeführten Studie wurden Thromben in der Arteria carotis communis von Ratten nach einer zuerst von Meng und Seuter (1977) beschriebenen Methode experimentell erzeugt. Induktion der Thrombusbildung erfolgte in vivo durch Unterkühlung eines kleinen Gefäßabschnittes unter konstantem Druck und kurzfristiger Stase. Eine Änderung des Blutflusses wurde durch einen Silberclip erzeugt. Die geschädigten Gefäßsegmente einschließlich der Thromben bzw. deren Vorstufen wurden nach 5, 10, 30 min und 1, 4 und 24 h nach der Thrombosestimulation entnommen und fixiert. Semidünnschnitte und Ultradünnschnitte wurden im Licht- und Elektronenmikroskop morphologisch untersucht.Den Transformationsvorgängen im Thrombus konnten exakte Zeitmarken zugeordnet werden. Als wichtigstes histopathologisches Merkmal für die Altersbestimmung arterieller Thromben in der Frühphase der Thrombogenese werteten wir die Querstreifung der Fibrinfasern. Diese trat bereits nach 5 min auf, erreichte nach 30 min ein Maximum und verschwand als Folge der zunehmenden Verdichtung der Fasern nach einer Stunde. Nach 4 h sahen wir eine weitgehende Retraktion der Fibrinfasern, die nach 24 h zur Bildung des Fibrinfasergerüstes mit Einmauerung korpuskulärer Elemente führte. Überdies beobachteten wir zwei Thrombocytenaggregate von differenter Struktur. Wir unterschieden ein fibrinarmes Aggregat, in dem die Thrombocyten dichtgepackt und pseudopodienreich erschienen von einem thrombocytenarmen Aggregat mit reichlich interponierten Fibrinfasern. Die nach 5 min im Zentrum des Thrombus auftretende Agglutination der Plättchen im thrombocytenreichen Aggregat führte nach 30 min zur Thrombocytorrhexis und ergab daher einen weiteren Anhalt für die Altersbestimmung des Coagulum. Der entstandene celluläre Abraum stimulierte mononucleäre Zellen und Leukocyten zur Phagocytose. Daher sahen wir nach 4 h eine massive Leukocytose als Folge der frühen Thrombocytorrhexis. Nach 24 h war die viscöse Metamorphose im fibrinreichen und fibrinararmen Aggregat weitgehend abgeschlossen. Innerhalb des beobachteten Zeitraumes entstand eine Verballung und bizarre Deformierung der Erythrocyten, die bereits nach 5 min vom Zentrum des Thrombus ausging und nach 24 h die Peripherie erreichte. Eine Hämolyse der Erythrocyten war nach dieser Zeit noch nicht erkennbar.
Evolution in the early changes in the establishment of arterial thrombi
Summary Ultrastructural studies of thrombi were carried out on the common carotid artery of the rat using a method first described by Meng and Seuter (1977). Induction of thrombus formation in vivo was achieved by chilling of a small vessel segment under constant pressure and short-termed stasis. Disturbance of the blood flow was produced by a silver clip. The damaged vessel segments with the thrombotic deposits were removed 5, 10, 30 min, and 1, 4 and 24 h after stimulation of thrombosis. They were fixed and samples were studied as semithin and ultrathin sections morphologically using light and electronmicroscopy.In the maturation of thrombi exact time intervals could be determined. The most important histopathological characteristics for age determination of arterial thrombi in the early period of thrombogenesis were the cross stripes of fibrin fibres. They appeared after 5 min, reaching a maximum after 10 min and disappeared as a result of increasing fibre density after 1 h. After 4 h nearly complete retraction of fibrin fibres was found which led after 24 h to the formation of a corresponding frame walling in the corpuscular elements. Apart from this aggregation of thrombocytes, which were of two different types were observed, one showing a fibrin-poor aggregate in which the thrombocytes appeared densely packed with numerous pseudopods, and one showing a thrombocyte poor aggregate with abundant interposed fibrin fibres. Agglutination of platelets which occurred in the thrombocyte-rich aggregate in the centre of the thrombus after 5 min led to thrombocytorrhexis after 30 min. The resulting cellular waste stimulated phagocytosis by mononuclear cells and leucocytes. Because of this a massive leucocytosis was found as a result of the early thrombocytorrhexis after 4 h. After 24 h the viscous metamorphosis in the fibrin-rich and in the fibrin-poor aggregate was largely completed. Clumping and deformation of erythrocytes was observed in the middle of the thrombus after 5 min and at the periphery of the thrombus after 24 h. Haemolysis did not occur within this time interval.
Frau Antoni, Herrn Ing. grad. Derks und Herrn Rieger sei für ausgezeichnete technische Assistenz herzlichst gedankt. 相似文献