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101.
CA Davies SA Loddick RP Stroemer J Hunt NJ Rothwell 《Canadian Metallurgical Quarterly》1998,154(1):199-212
Defining the chronology and severity of cell damage in an evolving lesion after ischemia is important for understanding the underlying mechanisms in the development of therapeutic intervention. In the present study, we used a combination of histological and immunocytochemical methods to evaluate cell responses from 30 min to 48 h after permanent occlusion of the middle cerebral artery (MCAO) in the rat. Specific immunocytochemical markers clearly revealed acute early responses in neurons (neurofilament protein 200), astrocytes (glial fibrillary acidic protein), and microglia/macrophages (OX-42 and ED-1) such as enlarged, convoluted neuronal processes, and disintegration of glia. Progressive topographic changes in the developing lesion, pinpointed by immunolabeling, indicated the severity and extension of the cell damage. Proliferation and hypertrophy of astrocytes and microglia around the infarct, and contralaterally, occurred 24-48 h after MCAO and coincided with mass necrosis and infiltration of neutrophils and macrophages into the core. These observations corroborate the suggestion that the inflammatory process is involved in the progression of the infarct. 相似文献
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A Bensoussan NJ Talley M Hing R Menzies A Guo M Ngu 《Canadian Metallurgical Quarterly》1998,280(18):1585-1589
CONTEXT: Irritable bowel syndrome (IBS) is a common functional bowel disorder for which there is no reliable medical treatment. OBJECTIVE: To determine whether Chinese herbal medicine (CHM) is of any benefit in the treatment of IBS. DESIGN: Randomized, double-blind, placebo-controlled trial conducted during 1996 through 1997. SETTING: Patients were recruited through 2 teaching hospitals and 5 private practices of gastroenterologists, and received CHM in 3 Chinese herbal clinics. PATIENTS: A total of 116 patients who fulfilled the Rome criteria, an established standard for diagnosis of IBS. INTERVENTION: Patients were randomly allocated to 1 of 3 treatment groups: individualized Chinese herbal formulations (n = 38), a standard Chinese herbal formulation (n = 43), or placebo (n = 35). Patients received 5 capsules 3 times daily for 16 weeks and were evaluated regularly by a traditional Chinese herbalist and by a gastroenterologist. Patients, gastroenterologists, and herbalists were all blinded to treatment group. MAIN OUTCOME MEASURES: Change in total bowel symptom scale scores and global improvement assessed by patients and gastroenterologists and change in the degree of interference in life caused by IBS symptoms assessed by patients. RESULTS: Compared with patients in the placebo group, patients in the active treatment groups (standard and individualized CHM) had significant improvement in bowel symptom scores as rated by patients (P=.03) and by gastroenterologists (P=.001), and significant global improvement as rated by patients (P=.007) and by gastroenterologists (P=.002). Patients reported that treatment significantly reduced the degree of interference with life caused by IBS symptoms (P=.03). Chinese herbal formulations individually tailored to the patient proved no more effective than standard CHM treatment. On follow-up 14 weeks after completion of treatment, only the individualized CHM treatment group maintained improvement. CONCLUSION: Chinese herbal formulations appear to offer improvement in symptoms for some patients with IBS. 相似文献
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Thin films of LiCoO2 have been synthesized in which the strongest x-ray reflection is either weak or missing, indicating a high degree of preferred orientation. Thin film solid state batteries with these textured cathode films can deliver practical capacities at high current densities. For example, for one of the cells, 70% of the maximum capacity between 4.2 and 3 V (approximately 0.2 mAh/cm2) was delivered at a current of 2 mA/cm2. When cycled at rates of 0.1 mA/cm2, the capacity loss was < or = 0.001%/cycle. The reliability and performance of Li-LiCoO2 thin film batteries make them attractive for application in implantable devices such as neural stimulators, pacemakers, and defibrillators. 相似文献
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107.
NJ Siegel RA Feldman B Lytton JP Hayslett M Kashgarian 《Canadian Metallurgical Quarterly》1977,40(4):379-384
To examine the role of intrarenal hemodynamics in in obstructive nephropathy, we determined cortical blood flow distribution (CBFD) in rats with bilateral ureteral occlusion (BUO) and unilateral ureteral occlusion (UUO) during and after release of obstruction. Prior to release of obstruction of 24 hours' duration, we found that outer cortical perfusion decreased by 20+/-5% in both BUO and UUO rats. Furthermore, one hour after release of BUO, there was rapid normalization of CBFD associated with a modest return of glomerular filtration rate (GFR), an almost complete return of renal blood flow (RBF), and a marked postobstructive diuresis. In contrast, after release of UUO, we observed that outer cortical perfusion remained decreased by 21+/-31%, both GFR and RBF remained markedly depressed, and no diuresis occurred. These data demonstrate (1) marked ischemia of the outer cortex in both BUO and UUO during obstruction, (2) a rapid return of CBFD to a normal pattern after release of BUO, but (3) persistent outer cortical ischemia following release of UUO. 相似文献
108.
Three patients with the rare association of secundum ASD and congenital clefts of A-V valves are reported. These three patients illustrate the predictive valve of vectoracardiographic analysis in precisely determining the anatomic location of the valvular pathology. The embryologic origins of the lesion are briefly discussed. A review of the literature supports the use of vector analysis in the evaluation of the patients with this type of heart disease. 相似文献
109.
p70s6k function is essential for G1 progression 总被引:2,自引:0,他引:2
An essential step in the pathway by which growth factors trigger cellular proliferation is the induction of high levels of protein synthesis. This appears in part to be controlled by multiple phosphorylation of the ribosomal protein S6 (refs 4, 5). The main kinase responsible, p70s6k (refs 6-8), is activated through the phosphorylation of four sites clustered in a putative autoinhibitory domain, which is mediated by a signalling pathway distinct from those used by other well characterized mitogen-activated serine/threonine kinases (such as p42/p44mapk or p90rsk; refs 10, 11). Here we investigate the role of p70s6k in the mitogenic response. Microinjection of quiescent rat embryo fibroblasts with any of three distinct polyclonal antibodies to p70s6k abolishes serum-induced entry into S phase of the cell cycle. This effect is preceded by almost complete abrogation of the activation of protein synthesis and the expression of an essential immediate early gene product, c-fos. The inhibitory effect on DNA synthesis is also elicited by microinjection of the antibodies late in G1 phase, consistent with the finding that p70s6k activity remains high throughout G1. 相似文献
110.