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排序方式: 共有3309条查询结果,搜索用时 78 毫秒
1.
Konstantin V. Dergilev Evgeny K. Shevchenko Zoya I. Tsokolaeva Irina B. Beloglazova Ekaterina S. Zubkova Maria A. Boldyreva Mikhail Yu. Menshikov Elizaveta I. Ratner Dmitry Penkov Yelena V. Parfyonova 《International journal of molecular sciences》2020,21(24)
Cell therapy of the post-infarcted myocardium is still far from clinical use. Poor survival of transplanted cells, insufficient regeneration, and replacement of the damaged tissue limit the potential of currently available cell-based techniques. In this study, we generated a multilayered construct from adipose-derived mesenchymal stromal cells (MSCs) modified to secrete stem cell factor, SCF. In a rat model of myocardium infarction, we show that transplantation of SCF producing cell sheet induced activation of the epicardium and promoted the accumulation of c-kit positive cells in ischemic muscle. Morphometry showed the reduction of infarct size (16%) and a left ventricle expansion index (0.12) in the treatment group compared to controls (24–28%; 0.17–0.32). The ratio of viable myocardium was more than 1.5-fold higher, reaching 49% compared to the control (28%) or unmodified cell sheet group (30%). Finally, by day 30 after myocardium infarction, SCF-producing cell sheet transplantation increased left ventricle ejection fraction from 37% in the control sham-operated group to 53%. Our results suggest that, combining the genetic modification of MSCs and their assembly into a multilayered construct, we can provide prolonged pleiotropic effects to the damaged heart, induce endogenous regenerative processes, and improve cardiac function. 相似文献
2.
IH Bjerkli R Myklebust S R?is?nen S Telimaa LE Stenfors 《Canadian Metallurgical Quarterly》1996,36(3):205-213
Dopaminergic agents and carbidopa/levodopa have become the preferred treatment for both the restless legs (RL) syndrome and for periodic limb movements in sleep (PLMS). For once-nightly treatments with carbidopa/ levodopa, a problem with morning end-of-dose rebound increases in leg movements has been reported to occur in the about one-fourth of the patients. In our clinical studies a previously unreported but far more significant problem of markedly augmented RL symptoms occurred in the afternoon and the evening prior to taking the next nightly dose. A systematic prospective evaluation of this augmentation in 46 consecutive patients treated with carbidopa/ levodopa for RL syndrome or PLMS disorder found this augmentation to be the major adverse effect of treatment. Augmentation occurred for 31% of PLMS patients and 82% of all RL patients. It was greater for subjects with more severe RL symptoms and for patients on higher doses (> or = 50/200 mg carbidopa/levodopa) but was unrelated to gender, age or baseline severity of PLMS. This augmentation was severe enough to require medication change for 50% of the RL patients and 13% of PLMS patients. Augmentation resolved with cessation of the medication and could be minimized by keeping the dose low. 相似文献
3.
Recurrent erosion of the corneal epithelium has been treated successfully by phototherapeutic keratectomy when convention therapy has failed. We present a case of recurrent corneal erosion occurring 1 year after photorefractive keratectomy in a 55-year-old myopic woman. No corneal abnormalities were previously identified in either the affected or the fellow eye. This case demonstrates the potential for ineffective healing of the corneal epithelial basement membrane complex after excimer laser photorefractive keratectomy. 相似文献
4.
LE Lindner 《Canadian Metallurgical Quarterly》1993,41(3):439-445
The silver-staining technique for nucleolar organizer regions (AgNOR) of Ploton et al., as popularized by Crocker, is being widely used for evaluation of nucleolar function, especially in neoplasia. It suffers from limited reliability, background staining, precipitates, and fading of the sections. Factors were identified that affect these problems. The oxidation-reduction level and gelatin used are particularly important. An improved procedure is presented which incorporates pre-reduction of the sections, selection of an optimal gelatin, and post-treatment of the sections to produce a permanent preparation. It is compatible with many fixatives and with other stains used before or after the silver stain. 相似文献
5.
D Averill D Blockus B Brabson J Brom C Jung H Ogren DR Rust M Derrick P Kooijman JS Loos B Musgrave LE Price J Repond K Sugano B Cork C Akerlof J Chapman D Errede MT Ken DI Meyer H Neal D Nitz R Thun R Tschirhart S Abachi P Baringer BG Bylsma R DeBonte D Koltick EH Low RL McIlwain DH Miller CR Ng EI Shibata 《Canadian Metallurgical Quarterly》1989,39(1):123-137
6.
7.
The technique of immunocytochemistry was used to identify myoglobin in kidney, confirming a diagnosis of neuroleptic malignant syndrome following an otherwise obscure autopsy in a decomposed body. The features of neuroleptic malignant syndrome are reviewed with a differential diagnosis of myoglobin renal casts. The report emphasizes a thorough and detailed assessment of deaths which occur during treatment with neuroleptic drugs. 相似文献
8.
We developed a new in vitro model of neuronal injury using NT2-N cells to examine the effects of hydrodynamic loading rate on intraneuronal calcium dynamics and lactate dehydrogenase (LDH) release. Our apparatus consisted of a parallel disk viscometer which induced fluid shear stress with well-defined magnitudes and loading rates to cultured cells. We found that the deformation response of the cells was dependent on the severity of the insult, with increased cellular strains generated for higher shear stresses at a constant loading rate. Peak intracellular free calcium concentration correlated with strain, suggesting that mechanical deformation may regulate calcium response. Slowly applied fluid shear stress elicited no response, whereas high loading rates resulted in peak calcium increases 2.9 to 3.6 times baseline values as injury severity was increased. LDH release measured within 5 min after the insult correlated with loading rate. In addition, LDH release continued to increase out to 24 h following high loading rate conditions, demonstrating that the application of fluid shear stress led to prolonged cell damage. The acute response in NT2-N cells subjected to an insult with the CSID is dependent on the loading rate, and these results suggest that initial membrane deformation may trigger subsequent events. 相似文献
9.
AK Souid MC Ziemba AS Dubansky M Mazur M Oliphant FD Thomas M Ratner PD Sadowitz 《Canadian Metallurgical Quarterly》1993,72(6):2042-2048
The authors presented the cases of two children with inflammatory myofibroblastic (IMF) tumor and reviewed the literature to facilitate the preoperative recognition, delineate the clinical features, and describe the natural history of this entity. The first child had IMF tumor arising from the mesentery of the small intestine. He presented with an abdominal mass associated with severe inflammatory response manifested by fever, impaired growth, thrombocytosis, and microcytic, hypochromic anemia. After surgical resection, his fever resolved and his growth rate and the laboratory abnormalities normalized. Five months after initial diagnosis, the fever, anemia, and thrombocytosis recurred along with two tumors arising from the omentum and the abdominal soft tissue. After the second surgery, he remains free of recurrent disease for 30 months. The second child presented with a lung mass that was radiologically indistinguishable from pulmonary sequestration. After surgical resection, she remains free of recurrent disease for 18 months. IMF tumor should be considered in any solid tumor that occurs in association with a chronic inflammatory response. IMF tumor should also be considered in the differential diagnosis of pulmonary sequestration. 相似文献
10.
TF Tihanyi K Morvay L Nehéz T Winternitz Z Rusz LE Flautner 《Canadian Metallurgical Quarterly》1997,36(1-4):359-361
Management of the pancreatic diseases is still a challenge to the laparoscopic technique. Some experience has been gained in the laparoscopic exploration of the pancreas and staging in cancer. Anatomically the accessibility of the distal pancreas provides the laparoscopic approach technically feasible. Patient and method: A case of insuloma in the tail of the pancreas is presented, where distal pancreatic resection was performed laparoscopically with the preservation of the spleen. In a 55 years old female patient with typical clinical symptoms of hyperinsulinism CT identified a 3 cm large solid tumor in the tail of the pancreas. Complete mobilization of the distal pancreas was enhanced by the use of an ultrasonic dissector (UltraCision). The pancreas is detached from the splenic hilum after dividing the spleen vessels. The pancreas is transected proximally by laparoscopic linear stapler. Preservation of the short gastric vessels provides the necessary blood supply of the spleen following division of the splenic artery and vein. Thus removal of the spleen is not a necessary step in this procedure. The operation was carried out within 4.5 hours. Postoperative course was uneventful, the patient left the hospital on the 5th postoperative day. Advantages of the procedure were the earlier mobilization and shorter recovery time, less postoperative pain. The procedure can be safely performed with a good experience in both pancreatic and laparoscopic surgery. 相似文献