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991.
Significantly reduced expression of the proteoglycan decorin in Alzheimer''s disease fibroblasts 下载免费PDF全文
Enrique Brandan Francisco Melo María García Maribel Contreras 《Journal of clinical pathology》1996,49(6):M351-M356
Aims—To investigate whether proteoglycan synthesis is altered in skin fibroblasts in patients with Alzheimer's disease compared with normal subjects. 相似文献
992.
本文报导了用人胎儿胸腺细胞免疫BALB/c小鼠,取其脾细胞与小鼠骨髓瘤细胞系NS-1融合,获得一株能稳定分泌抗人共同性胸腺细胞单克隆抗体的杂交瘤细胞株,W_(?)T_(?)。它与72%胸腺细胞、皮肤Langerhan's细胞及部分T细胞系呈阳性反应;外周血T、D细胞、粒细胞、红细胞、血小板及B细胞系、Null细胞系均阴性。FACS检测结果及W_(?)T_(?)阳性细胞的组织分布特点均同HIT_6相似。在胸腺、皮质细胞及髓质中少数胞体较大呈树突状的细胞呈阳性反应。在扁桃体实质中少数散在细胞阳性。上皮基底层中的Langerhan's细胞则呈强阳性反应。用W_(?)T_(?)亲和层析柱提取胸腺细胞膜上相应的靶抗原分子,证明W_(?)T_(?)识别分子量为51KDa的抗原。免疫竞争抑制试验表明,W_(?)T_(?)同抗原的结合可被HIT_6完全阻断。说明W_(?)T_(?)与HIT_6识别相同的抗原决定簇。 相似文献
993.
E. Bouza C. Martín-Scapa J. C. L. Bernaldo de Quirós D. Martínez-Hernández J. Menarguez J. Gómez-Rodrigo J. Cosín M. J. Sagues-Cifuentes 《European journal of clinical microbiology & infectious diseases》1988,7(6):785-788
A total of 67 cases of tuberculosis was diagnosed in the first 100 cases of AIDS, diagnosed according to the former CDC criteria, at a hospital in Madrid, Spain. This is the highest known prevalence of tuberculosis in AIDS patients both within and outside Spain. The clinical manifestations of tuberculosis were very variable and atypical. The rate of isolation ofMycobacterium tuberculosis from blood was particularly high: of 25 patients in whom blood cultures were performed, 16 were positive. In a third of the patients with proven mycobacteremia, blood was the first or the only positive specimen. In general, therapy resulted in rapid clinical improvement, but in some cases mycobacteria were isolated from clinical or necroscopy specimens months after what was considered adequate therapy. 相似文献
994.
995.
Extracellular levels of adenosine and its metabolites in the striatum of awake rats: inhibition of uptake and metabolism 总被引:7,自引:0,他引:7
The level of purines in the striatum of awake, freely moving rats was studied using microdialysis. The calculated extracellular concentration of adenosine and its metabolites inosine and hypoxanthine was very high immediately after implantation of the dialysis probe but decreased within 24 h to a level which remained stable for two days. Using in vitro calibration to determine the relative recovery of the dialysis probes we estimated resting levels in the striatal extracellular space to be 40, 110 and 580 nM, respectively. Inhibition of adenosine deaminase by deoxycoformycin produced a significant 1.4-fold increase in extracellular adenosine levels and a fall in inosine and hypoxanthine. A combination of three uptake blockers (dipyridamole, lidoflazine and nitrobenzylthioinosine), caused a 4.5-fold increase in extracellular adenosine levels without any change in inosine or hypoxanthine levels. After uptake inhibition deoxycoformycin did not have any significant effect. The present results show that the microdialysis technique can be used to determine levels of purines in the extracellular fluid of defined brain regions in awake animals. The high levels recorded during the first several hours after implantation may be artefactually high and reflect trauma. The results also show that adenosine levels can be altered in vivo by inhibitors of adenosine transport and adenosine deaminase. The present results indicate that the physiological adenosine level in striatal extracellular space is in the range 40-460 nM. 相似文献
996.
General morphology and capsid fine structure of African swine fever virus particles 总被引:11,自引:0,他引:11
JoséL. Carrascosa JoséM. Carazo Angel L. Carrascosa Narciso García Antonio Santisteban Eladio Viñuela 《Virology》1984,132(1):160-172
The structure of African swine fever virus particles has been examined by electron microscopy. The analysis of virions prepared by negative staining, thin sectioning, and freeze-drying and shadowing showed that the virus particle was composed of several concentric structures with an overall icosahedral shape. The inner region of the virus particles was a nucleoid that was surrounded by a membrane covered by the capsid. The capsid had side-to-side dimensions of 172 to 191 nm and was built up by capsomers arranged in an hexagonal lattice. Computer-filtered electron micrographs of either negatively stained or freeze-dried and shadowed capsids revealed capsomers with a hexagonal outline and a hole in the center. The intercapsomer distance ranged from 7.4 to 8.1 nm. The triangulation number of the capsid was estimated to be 189 to 217, indicative of 1892 to 2172 capsomers. Extracellular African swine fever virus particles had an external membrane that resembled the cytoplasmic unit membrane. 相似文献
997.
A de novo translocation of 15q to 3p with complete monosomy of 15p and partial monosomy of 15q was detected by trypsin banding on peripheral lymphocytes of a 5-year-old boy with Prader-Willi syndrome (severe mental retardation, dyslalia, cryptorchidism, and muscular hypotonia). The pathogenic role of chromosome 15 abnormalities in the aetiology of this syndrome is discussed. 相似文献
998.
999.
Hník P. Holas M. Krekule I. Kříž N. Mejsnar J. Smieško V. Ujec E. Vyskočil F. 《Pflügers Archiv : European journal of physiology》1976,362(1):85-94
Using liquid ion-exchanger semimicroelectrodes with a side pore, we measured changes of extracellular potassium concentration (Ke
+) in adult rabbit and cat gastrocnemius muscles and in venous effluent blood flowing from the cat gastrocnemius muscle during various bouts of activity induced by sciatic nerve stimulation.
相似文献
1. | Isometric tetanic contractions (at 50 Hz) of various durations caused transient accumulation of Ke + which was non-linearly related to the duration of muscle activity. The peak values of Ke + in response to muscle stimulation were analogous in rabbits and cats, attaining values, e.g. after a 20-s isometric tetanus, between 8–9 mEq/lK+ in both species. |
2. | Potassium concentration in venous effluent blood (K ven + ) was transiently increased after isometric tetani. Since blood flow was measured at the same time, it was possible to calculate the amount of K+ lost by the muscle after tetani of various durations. A 32 g gastrocnemius muscle of the cat, for example, loses 9.36±1.52 EqK+ after a 20-s isometric tetanus, which corresponds roughly to 0.5% of the total muscle potassium content. The loss of K+ in this muscle was 29.3 pEq K+/impulse/100 g fresh muscle tissue. |
3. | There was no evident difference between the amount of K+ released during isometric tetani, or tetanic contractions performed under isotonic conditions. Single twitches evoked by indirect stimulation at 1 Hz for several minutes also induced a small rise in K ven + . |
4. | If the loss of K+ from the muscle into the blood stream is transiently prevented by arterio-venous occlusion installed immediately before a 10-s isometric tetanus, most K+ is released subsequently when blood flow is renewed, if the occlusion lasts for 20–25 s. It is not until blood flow is occluded for 40–60 s that most K+ is apparently resorbed and only a minor portion is released and is to be found in the venous blood. |
5. | The transient accumulation of muscle extracellular potassium may locally affect nerve endings, skeletal and smooth muscle cells. |
1000.
动态监测SARS病人IL-1α、IL-1β、TNFα和IL-6含量及其意义 总被引:1,自引:0,他引:1
目的 :动态监测SARS病人IL 1α、IL 1β、TNFα和IL 6含量并探讨其意义。方法 :采用酶联免疫吸附法定量检测早期、恢复期SARS病人以及出院后SARS随访者 ,一线未患SARS健康医护人员及健康体检者血清中IL 1α、IL 1β、TNFα和IL 6含量。结果 :IL 1α和IL 1β含量在早期、恢复期与其他组比较均显著升高 (P <0 0 5 )。SARS早期组TNFα均值显著高于其他组(P <0 0 0 5 ) ,SARS恢复期组均值显著高于SARS随访组、急诊等一线未患SARS组和健康对照组 (P <0 0 1)。SARS早期组IL 6均值显著高于其他各组 (P <0 0 0 5 ) ,SARS随访组与急诊等一线未患SARS组和健康对照组间均值比较 ,均有显著差异 (P <0 0 1)。结论 :SARS在发病过程中其病理损伤与细胞因子IL 1、TNFα和IL 6有关。 相似文献