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901.
902.
Tissue culture studies in Hodgkin’s disease morphologic, cytogenic, cell surface, and enzymatic properties of cultures derived from splenic tumors
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![点击此处可从《The Journal of experimental medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
JC Long PC Zamecnik AC Aisenberg L Atkins 《The Journal of experimental medicine》1977,145(6):1484-1500
Monolayer and suspension cell cultures prepared from Hodgkin's disease tumors in the spleen were examined microscopically and by cytogenetics, tested for lymphocyte and monocyte cell surface properties, and assayed for enzymes by histochemical and spectrophotometric techniques. Hodgkin's disease monolayer cultures were composed of rapidly proliferating round and polygonal cells that were capable of propagation in vitro for an indefinite period of time. Abnormal aneuploid chromosomes were found in short-term Hodgkin's disease monolayers that had been passaged 16-20 times, and in established cell lines carried in culture longer than 3 yr and passaged more than 200 times. Cells fromHodgkin's disease monolayers contained lysozyme (muramidase), fluoride-resistant alpha naphthol acetate esterase, acid and alkaline phosphatase, and chymotrypsin-like activity. The monolayers did not exhibit specific cell surface markers or phagocytosis. Suspension cultures derived from Hodgkin's disease monolayers were composed of cells with aneuploid karyotypes and similar enzymes. The Hodgkin's disease suspension culture cells had surface receptors for complement and IgGFc, lacked surface or cytoplasmic immunoglobulin, and did not form Erosettes, react with an antithymocyte serum, nor exhibit phagocytosis. Normal monolayer culture cells, derived from adult spleen and human fetal spleen and thymus, were composed of spindle cells with a diploid number of chromosomes that could be carried for only a finite period of time in vitro. Normal cultured cells contained similar esterases and phosphatases, but were devoid of lysozyme and chymotrypsin-like activity. The morphologic, cytogenetic, cell surface, and enzymatic findings indicate that our Hodgkin's disease monolayer and suspension cultures are composed of cells with many properties suggesting an origin from monocytes (macrophages) rather than lymphocytes or fibroblasts. The presence of aneuploid karyotypes is consistent with a neoplastic origin and derivation from a malignant cell of Hodgkin's disease. 相似文献
903.
Ira M. Mostovaya Peter J. Blankestijn Michiel L. Bots Adrian Covic Andrew Davenport Muriel P.C. Grooteman Jörgen Hegbrant Francesco Locatelli Raymond Vanholder Menso J. Nubé The EUDIAL – an official ERA‐EDTA Working Group 《Seminars in dialysis》2014,27(2):119-127
In this review, a systematic literature search and meta‐analysis were performed to assess the effects of hemodiafiltration (HDF) on clinical outcome, as compared with hemodialysis (HD). Furthermore, the relation between the convection volume in HDF and clinical outcome was studied. The literature search identified six randomized controlled trials (RCTs). In a meta‐analysis of these RCTs, HDF treatment was related to a decreased risk of mortality (RR: 0.84; 95% CI 0.73–0.96) and cardiovascular death (RR: 0.73; 95% CI 0.57–0.92). Post hoc analyses of the three largest RCTs suggested an inverse relation between the magnitude of convection volume and mortality risk. The evidence presented in this analysis supports a wider acceptance of HDF. 相似文献
904.
905.
906.
Evaluating the predictive value of doublecortin as a marker for adult neurogenesis in canaries (Serinus canaria)
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Michiel Vellema Moritz Hertel Susan L. Urbanus Annemie Van der Linden Manfred Gahr 《The Journal of comparative neurology》2014,522(6):1299-1315
Doublecortin (DCX) is an important microtubule‐associated protein involved in the migration of young neurons into the cortical layers of the brain during early human development. The continued expression of DCX in brain areas with protracted neuron recruitment has promoted this endogenous protein as a popular indirect tool to monitor adult neurogenesis in a variety of species. However, little is known about its possible involvement in other cellular processes and a thorough validation of DCX as a quantitative measure for neurogenesis is generally lacking. Here we investigated the relationship between DCX expression and neuron recruitment in the brains of adult canaries (Serinus canaria), a species well‐known for its adult neurogenesis. We examined the age and functional state of DCX‐labeled cells by using mitotic and neuron‐specific markers, retrograde tracings, and immediate early gene colocalizations. Although DCX expression was high in brain areas implicated in adult neurogenesis, DCX‐expressing neurons were also abundant in regions that do not recruit new neurons. Moreover, DCX expression was observed in adult, active neurons, differentiated projection neurons, and birth‐dated neurons of up to 1 year of age. Season and testosterone treatment affected DCX expression in two song control nuclei, HVC and Area X, but did not correlate with known patterns of neuron recruitment. Together, these results demonstrate that DCX expression is not exclusive to young migrating neurons, and does not predict neuron recruitment equally throughout the canary brain. Therefore, DCX labeling needs careful validation for each brain region separately in each species analyzed when used to quantify adult neurogenesis. J. Comp. Neurol. 522:1299–1315, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
907.
908.
Mark J C Smeulders Michiel Kreulen J Joris Hage Peter A Huijing Chantal M A M van der Horst 《Journal of orthopaedic research》2004,22(6):1331-1335
To answer the question whether the muscle contracture in patients with cerebral palsy is caused by overstretching of in-series sarcomeres we studied the active and passive force-length relationship of the flexor carpi ulnaris muscle (FCU) in relation to its operating length range in 14 such patients with a flexion deformity of the wrist. Force-length relationship was measured intra-operatively using electrical stimulation, a force transducer, and a data-acquisition system. Muscle length was measured in maximally flexed and maximally extended position of the wrist. The spastic FCU was found to exert over 80% of its maximum active force at maximal extension of the wrist and this indicates abundant overlap of the sarcomeres. At maximal wrist extension, FCU passive force corresponded with only 0.7-18% of maximum active force. Both findings imply that the FCU sarcomeres are not overstretched when the wrist is extended. We conclude that the overstretching of in-series sarcomeres appears not to be the cause of contracture of the spastic FCU. 相似文献
909.
Cindy van den Boer Sara H. Muller Andrew D. Vincent Klaus Züchner Michiel W. M. van den Brekel Frans J. M. Hilgers 《European archives of oto-rhino-laryngology》2014,271(2):359-366
Laryngectomized patients suffer from respiratory complaints due to insufficient warming and humidification of inspired air in the upper respiratory tract. Improvement of pulmonary humidification with significant reduction of pulmonary complaints is achieved by the application of a heat and moisture exchanger (HME) over the tracheostoma. The aim of this study was to determine whether the new Provox HMEs (XM-HME and XF-HME) have a better water exchange performance than their predecessors (R-HME and L-HME, respectively; Atos Medical, Hörby, Sweden). The other aim was to assess the short-term clinical feasibility of these HMEs. The XM-HME and XF-HME were weighed at the end of inspiration and at the end of expiration at different breathing volumes produced by a healthy volunteer. The associations between weight changes, breathing volume and absolute humidity were determined using both linear and non-linear mixed effects models. Study-specific questionnaires and tally sheets were used in the clinical feasibility study. The weight change of the XM-HME is 3.6 mg, this is significantly higher than that of the R-HME (2.0 mg). The weight change of the XF-HME (2.0 mg) was not significantly higher than that of the L-HME (1.8 mg). The absolute humidity values of both XM- and XF-HME were significantly higher than that of their predecessors. The clinical feasibility study did not reveal any practical problems over the course of 3 weeks. The XM-HME has a significantly better water exchange performance than its predecessor (R-HME). Both newly designed HMEs did succeed in the clinical feasibility study. 相似文献
910.
Cindy van den Boer Michel C. van Harten Frans J. M. Hilgers Michiel W. M. van den Brekel Valesca P. Retèl 《European archives of oto-rhino-laryngology》2014,271(12):3297-3303
Laryngectomized patients, lacking conditioning of the breathing air in the upper respiratory tract, have reported considerable pulmonary complaints. It is assumed that these patients also run a higher risk of developing severe respiratory infections. Unfortunately, there is little scientific information available about the occurrence of respiratory infections and related health costs in these patients with and without the use of an HME. Therefore, the occurrence of respiratory infections in laryngectomized patients was investigated in the Netherlands Cancer Institute and by means of a survey among head and neck oncology surgeons throughout Europe. The number of tracheobronchitis and/or pneumonia events was retrospectively scored between 1973 and 2013 in medical records of 89 laryngectomized patients treated in our institute. To assess expert experiences and opinions regarding these pulmonary problems, a study-specific survey was developed. The survey was sent by email to head and neck surgeons from ten different countries. In the medical record study, an average of 0.129 respiratory infections per patient/year was found in non-HME users and 0.092 in HME users. In the survey (response rate HN surgeons 20 %; countries 90 %) 0.285 episodes per patient/year in non-HME users was statistically higher than the 0.066 episodes per patient/year in HME users. The average mortality in the HME user group per entire career of each physician was estimated at 0.0045, and for the non-HME user group this was 0.0152. There is a tendency that the number of tracheobronchitis and pneumonia episodes in non-HME users is higher than in HME users. 相似文献