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41.
42.
火把花根片对哮喘豚鼠气道炎症抑制作用的实验研究 总被引:3,自引:0,他引:3
目的 研究火把花根片对哮喘豚鼠气道炎症的作用。方法 建立哮喘豚鼠动物模型。豚鼠17只随机分为2组,即对照组(8只)和火把花根组(9只)。测定支气管肺泡灌洗液(BAIF)细胞总数、嗜酸性粒细胞、淋巴细胞、中性粒细胞数量及蛋白浓度,图像分析软件测定气道壁厚度及腺体厚度。结果 火把花根组BAIF细胞总数、嗜酸性较细胞为主的炎性细胞数量及蛋白浓度均低于对照组(P<0.01),图像分析表明火把花根组气道壁厚度及腺体厚度均较对照组减低(P<0.01)。结论 火把花根片可抑制哮喘豚鼠的气道慢性炎症,对支气管哮喘有治疗作用。 相似文献
43.
Serial in vivo MR tracking of magnetically labeled neural spheres transplanted in chronic EAE mice. 总被引:5,自引:0,他引:5
Tamir Ben-Hur Ruud B van Heeswijk Ofira Einstein Michal Aharonowiz Rong Xue Emma E Frost Susumu Mori Benjamin E Reubinoff Jeff W M Bulte 《Magnetic resonance in medicine》2007,57(1):164-171
Neural stem cell (NSC) transplantation has been shown to attenuate the severity of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Central to the future success of NSC transplantation in MS is the ability of transplanted cells to migrate from the site of transplantation to relevant foci of disease. Using magnetically labeled mouse neurospheres and human embryonic stem cell (hESC)-derived neurospheres, we applied serial magnetic resonance imaging (MRI) to assess the biodynamics of transplanted cell migration in a chronic mouse EAE model. Magnetic labeling did not affect the in vitro and in vivo characteristics of cells as multipotential precursors. Cell migration occurred along white matter (WM) tracts (especially the corpus callosum (CC), fimbria, and internal capsule), predominantly early in the acute phase of disease, and in an asymmetric manner. The distance of cell migration correlated well with clinical severity of disease and the number of microglia in the WM tracts, supporting the notion that inflammatory signals promote transplanted cell migration. This study shows for the first time that hESC-derived neural precursors also respond to tissue signals in an MS model, similarly to rodent cells. The results are directly relevant for designing and optimizing cell therapies for MS, and achieving a better understanding of in vivo cell dynamics and cell-tissue interactions. 相似文献
44.
Arto J. Turunen José A. Fernández Leena Lindgren Kaija T. Salmela Lauri E. Kyllönen Heikki Mäkisalo John H. Griffin Sanna M. Siitonen Jari Petäjä Eero J. Pesonen 《American journal of transplantation》2005,5(9):2204-2212
We studied the role of endogenous activated protein C (APC), the major physiological anti-coagulant with concomitant anti-inflammatory properties, on ischemia/reperfusion (I/R) in 45 patients participating in a larger trial comparing three immunosuppressive protocols in cadaveric renal transplantation: perioperative anti-thymocyte globulin (ATG, Fresenius AG, Bad Homburg, Germany), perioperative basiliximab and conventional triple therapy. Blood samples for assessing plasma APC, protein C, and lactoferrin concentrations, neutrophil CD11b and L-selectin expressions and blood leukocyte differential counts were obtained preoperatively and before reperfusion from central venous cannula, complemented with simultaneous samples from iliac artery and graft vein for calculation of transrenal differences (Delta) of study parameters at 1 and 5 min after reperfusion. Unlike basiliximab or conventional therapy groups, ATG infusion induced a substantial increase in plasma APC concentration (119 [88-144]% before infusion vs. 232 [85-1246]% after infusion, p<0.001), resulting in renal graft sequestration of APC at 1 min after reperfusion (Delta=-72 [-567 to 12]%, p<0.001). Graft APC consumption was associated with transrenal reduction of neutrophil activation markers (L-selectin r=0.7, p=0.01; lactoferrin r=-0.6, p=0.02; CD11b r=-0.8, p=0.001), and with both warm (r=0.6, p=0.01) and cold ischemia time (r=0.6, p=0.02) and donor age (r=0.6, p=0.01). These findings suggest that APC has an anti-inflammatory role in I/R injury in clinical renal transplantation. 相似文献
45.
46.
P. L. Sakellariou 《Dental traumatology》1996,12(3):151-154
Abstract This case of periapical actinomycosis presented the clinical picture of chronic periapical inflammation. The diagnosis was based on the histological examination of the periapical lesions suggesting the necessity for routine histological examination. Although root canals provide a primary port of entry the Actinomyces organisms into the periapical tissue, periapical actinomycosis, is considered extremely rare. This may be due to the omission of routine histological examination of periapical lesions and the clinical behavior of the disease. The large number of cases reported during the last decade indicates that periapical actinomycosis is more frequent than what it is believed and this is important in the daily dental practice. 相似文献
47.
The effects of cysteamine on the upper gastrointestinal tract of children with cystinosis 总被引:1,自引:0,他引:1
The purpose of this study was to evaluate the effects of cysteamine on gastric acid output and serum gastrin levels in children
with nephropathic cystinosis. We studied four children with nephropathic cystinosis receiving a dose of free base cysteamine
of 14.35 mg/kg four times a day (range 12.30 – 18.80 mg/kg). Gastric acid was measured for the hour before and after administration
of the medication. Serum gastrin levels were obtained at 0, 30, 60, and 90 min following the medication. Gastrointestinal
anatomy was evaluated by endoscopy and biopsy. Following administration of the medication, all subjects showed an increase
in gastric acid output. Mean acid output increased from 0.79 to 2.22 mEq/h. Mean gastric acid output adjusted for body weight
increased from 0.03 to 0.09 mEq/kg per hour. Following administration of the medication, all subjects showed an increase in
serum gastrin. The mean increase above the base value was 38.3 pg/dl. Two of the four subjects demonstrated visual and histological
evidence of inflammation. Cysteamine has a marked effect on gastric acid production and serum gastrin, even at the dose used
in children with nephropathic cystinosis. The clinical effect of this acid production is unknown but may be significant.
Received February 13, 1996; received in revised form February 25, 1997; accepted February 27, 1997 相似文献
48.
Magnetic resonance imaging (MRI) has greatly facilitated morphologic evaluation of spinal cord lesions. Eleven cases representative of inflammatory, demyelinating, neoplastic and vascular diseases, are presented which illustrate and summarize important abnormal features in spinal cord imaging, particularly MR findings. Recently, specialised techniques such as MR angiography, fat-inhibiting methods, dynamic MRI and functional imaging have been developed. These methods have facilitated not only lesion diagnosis but also qualitative assessment, and are being used to analyze pathophysiology. Comprehensive diagnoses based on such modalities may be important in determining indications for surgery or defining the extent of surgery or the intensity of other treatments. 相似文献
49.
Convergence of Genetic, Nutritional and Inflammatory Factors in Gastrointestinal Cancers 总被引:2,自引:0,他引:2
Gastrointestinal cancers account for 20% of all cancer incidences worldwide. Colorectal cancer is the second most common cause of all cancer-related mortality and is increasing in Western societies. Infection and inflammation contribute to 15–20% of all malignancies, and are predisposing risk factors for gastrointestinal cancers. Helicobacter pylori infection is commonly associated with gastric cancers, and chronic inflammation increases the risk of colorectal cancer by 1% per year. Micronutrient status and common genetic variations in human populations modify risk for gastrointestinal cancer. Chronic inflammation promotes carcinogenesis by inducing gene mutations, inhibiting apoptosis, and stimulating an-giogenesis and cell proliferation. Inflammation also induces epigenetic alterations that are associated with cancer development. Two key genes in the inflammatory process, cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-kB), provide a mechanistic link between inflammation and cancer and are targets for chemoprevention. Dietary components, and human genetic variation that affects nutrient utilization, can directly modify inflammatory processes and/or suppress genomic alterations that are the molecular antecedents of cancers. The present report focuses on the convergence of genetic, nutritional, and inflammatory factors in the initiation and progression of gastrointestinal cancers, and the emerging dietary strategies for cancer prevention. 相似文献
50.
Splanchnic ischaemia and its role in multiple organ failure 总被引:3,自引:0,他引:3
Multiple organ failure remains the leading cause of death in the intensive care unit. Increasing numbers of investigators have focused their attention on the role of gastrointestinal tract in the pathogenesis of this syndrome. Their data indicate that inadequate gut perfusion leads to a measurable imbalance between oxygen delivery and the needs of the tissues, i.e., ischaemia. Gut ischaemia of sufficient duration impairs gastrointestinal tract barrier function, facilitating the passage of enteric bacterial endotoxin into the circulation. It has been hypothesized that production of tumor necrosis factor α, and other biologic mediators by endotoxin–stimulated macrophages, triggers a generalized and uncontrolled inflammatory response that ultimately leads to multiple organ failure.
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed. 相似文献
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed. 相似文献