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排序方式: 共有732条查询结果,搜索用时 15 毫秒
81.
Schlachetzki F Hoelscher T Dorenbeck U Greiffenberg B Marienhagen J Ullrich OW Bogdahn U 《Ultrasound in medicine & biology》2001,27(1):21-31
To investigate new methods of diagnostic transcranial sonography for brain parenchymal, vascular and perfusion imaging, we performed 3-D native tissue harmonic transcranial sonography (3D-nthTCS), 3-D transcranial color-coded duplex sonography (3D-TCCS), and "loss-of-correlation" imaging (LOC-TCCS) in four patients following early hemicraniectomy due to space-occupying "malignant" middle cerebral artery infarction (MMCAI). Three-dimensional datasets, utilizing 3D-nthTCS and 3D-TCCS, were created and up to 10 axial 2-D B-mode image planes, similar to CCT, reconstructed in each patient. Three-dimensional reconstructions of the circle of Willis documented one persistent carotid-T occlusion and three recanalizations of the MCA. LOC-TCCS, based on stimulated acoustic emission from an ultrasound (US) contrast agent, demonstrated a perfusion deficit in 2 of 3 patients, with regard to their infarcts. Concluding, 3D-nthTCS, 3D-TCCS and LOC-TCCS are promising tools for bedside monitoring, early prognosis and treatment evaluation for MMCAI in the postoperative period. Further studies should be performed to standardize these new methods and evaluate their applications through the intact calvarina. 相似文献
82.
The inactivation of HIV by gamma-radiation was studied in frozen and liquid plasma; a reduction of the virus titer of 5 to 6 logs was achieved at doses of 5 to 10 Mrad at -80 degrees C and 2.5 Mrad at 15 degrees C. The effect of irradiation on the biologic activity of a number of coagulation factors in plasma and in lyophilized concentrates of factor VIII (FVIII) and prothrombin complex was examined. A recovery of 85 percent of the biologic activity of therapeutic components present in frozen plasma and in lyophilized coagulation factor concentrates was reached at radiation doses as low as 1.5 and 0.5 Mrad, respectively. As derived from the first-order radiation inactivation curves, the radiosensitive target size of HIV was estimated to be 1 to 3 MDa; the target size of FVIII was estimated to be 130 to 160 kDa. Gamma radiation must be disregarded as a method for the sterilization of plasma and plasma-derived products, because of the low reduction of virus infectivity at radiation doses that still give acceptable recovery of biologic activity of plasma components. 相似文献
83.
Gruber HE Hoelscher GL Ingram JA Bethea S Zinchenko N Hanley EN 《Experimental and molecular pathology》2011,(2):534-539
During disk degeneration, annulus dehydration and matrix fraying culminate in the formation of tears through which nucleus and annulus disk material may rupture, causing radicular pain. Annular tears are present in more than half of the patients in early adulthood and are almost always present in the elderly. Aggrecan, which provides the disk with a shock absorber function under loading, is a key disk extracellular matrix (ECM) component. The objective of the present study was to assess the immunolocalization of aggrecan in the annulus, and to assess molecular gene expression patterns in the annulus ECM utilizing microarray analysis. Immunohistochemistry was performed on 45 specimens using an anti-human aggrecan antibody. Affymetrix microarray gene expression studies used the extracellular matrix ontology approach to evaluate an additional 6 grade I–II, 9 grade III, and 4 grade IV disks. Grade III/IV disks were compared to healthier grade I/II disks. Healthy and less degenerated disks showed a general uniform aggrecan immunolocalization; more degenerated disks contained regions with little or no identifiable aggrecan localization. In degenerated disks, molecular studies showed a significant downregulation of aggrecan, ADAMTS-like 3, and ADAMTS10. Collagen types III and VIII, fibronectin, decorin, connective tissue growth factor, TIMP-3, latent TGF-β binding protein 2 and TGF-β1 were significantly upregulated with fold changes ranging from 2.4 to 9.8. Findings here help us better understand changes in the immunohistochemical distribution of a key proteoglycan during disk aging. Such information may have application as we work towards biologic therapies to improve the aging/degenerating disk matrix. 相似文献
84.
Frederike C. Ling Arnulf H. Hoelscher Daniel Vallböhmer Daniel Schmidt Susanne Picker Birgit S. Gathof Elfriede Bollschweiler Paul M. Schneider 《Journal of gastrointestinal surgery》2009,13(4):581-586
Background Perioperative transfusion of allogeneic blood has been hypothesized to have an immunomodulatory effect and influence survival
in several cancer types. This study evaluates the association between receipt of leucocyte-depleted and non-depleted allogeneic
blood and survival following esophagectomy for cancer.
Methods A retrospective analysis was performed including 291 patients with esophageal cancers who underwent transthoracic en bloc
esophagectomy and extended mediastinal lymphadenectomy. Neoadjuvant chemoradiation was administered in 152 (52.2%) patients.
Perioperative blood transfusions were quantified and the potential prognostic cutoff for transfused units was calculated according
to LeBlanc.
Results The median number of perioperative blood transfusions was 2 (0–24), and 106 patients (36.4%) received no transfusions. Patients
with one or less blood transfusion showed a significantly improved survival compared to patients receiving more than one unit
(p < 0.009). In multivariate analysis, blood transfusion categories showed significance (p < 0.015) next to pT, pN, pM category, and residual tumor categories (R-categories). Separate analysis of 183 patients treated
after the mandatory introduction of leukocyte-depleted blood transfusions detected a strong tendency, but no significant difference
in survival for patients getting one or less or more than one transfusion (p = 0.056). Receipt of leukocyte-depleted versus non-depleted units, however, had no influence on survival (p = 0.766).
Conclusions The need for perioperative allogeneic blood transfusions is significantly associated with poorer survival following resection
for esophageal cancer by univariate and multivariate analysis. Our data suggest that the reduction of leukocytes in allogeneic
transfusions is not sufficient to overcome the negative influence on survival.
This paper was presented at DDW 2008 in the San Diego Convention Center, San Diego, CA, May 17–22, 2008. 相似文献
85.
Helen E. Gruber PhD Gretchen Hoelscher MS Bryan Loeffler MD Yin Chow BS Jane A. Ingram BS Will Halligan BS Edward N. Hanley Jr. MD 《The spine journal》2009,9(9):760-766
Background contextEpidermal growth factor (EGF) is a peptide known to modulate a number of cellular responses including embryogenesis, cell proliferation, and cell survival. Little is known about EGF and its regulation in human annulus cells. Previous work has identified EGF and its receptor in control outer annulus disc tissue, but not in herniated tissue.PurposeTo determine if human annulus cells express EGF in vitro, to determine if the epidermal growth factor-receptor (EGF-r) was expressed in vivo and in vitro in disc cells, to test the effect of EGF on annulus cell proliferation and proteoglycan production in vitro, and to test the effect of prostaglandin E1 (PGE1) and misoprostol on disc cell production of EGF in vitro.Study design/settingStudies were approved by the authors' Human Subjects Institutional review Board. Human disc tissue was used for immunocytochemistry, and human annulus cells were tested in vitro.Patient sampleThirty-four disc specimens were used for studies of proteoglycan production, cell proliferation, and EGF production in vitro. An additional nine discs were used for EGF-r immunolocalization.MethodsDisc tissue was used for immunocytochemical studies for the localization of EGF-r and as a source for cultured annulus cells. Monolayer culture was used to test proliferation responses to 0, 25, 50, or 75 ng/mL EGF over a 2-day culture period. Three-dimensional (3D) culture in a collagen sponge was used to test 100,000 cells cultured in a paired experimental design over 14 days for production of EGF and proteoglycans. Cells were exposed to control conditions, or to either misoprostol at 8 ng/mL or PGE1 at 10?7 M. Conditioned media was harvested and assayed using an enzyme-linked immunosorbent assay (ELISA) assay with the Human Protein Cytokine Antibody Array I kit. Replicate EGF relative intensity values were averaged and normalized to controls assayed on the same membrane. 3D-cultured cells were also used to confirm EGF gene expression using microarray analysis. Standard statistical methods were used to analyze results.ResultsMicroarray analysis of mRNA from annulus cells in 3D culture confirmed expression of EGF, and immunocytochemistry verified the presence of EGF-r in vitro and in vivo. PGE1, at a dose of 10?7 M, and misoprostol (a synthetic PGE1 analog) at a dose of 8 ng/mL, both significantly increased EGF levels in annulus cells cultured in 3D compared with control levels (p=.031 and .034, respectively). No significant difference, however, was seen in cell proliferation or in total sulfated proteoglycan production in EGF-exposed annulus cells.ConclusionsData showed that EGF is expressed and produced by annulus cells in vivo and in 3D culture, with significantly greater in vitro EGF produced in the presence of PGE1 or the PGE1 analog misoprostol. Misoprostol, developed for prevention/treatment of nonsteroidal anti-inflammatory-induced gastropathy, has now been reported to have some interesting anabolic effects stimulating osteoblasts during fracture healing and during ovariectomy in animal models. Exogenous EGF did not increase cell proliferation in monolayer, or total production of proteoglycans in 3D culture. Additional work is needed to further delineate the role of EGF in the human disc. 相似文献
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Respiratory diseases and allergies in two polluted areas in East Germany. 总被引:13,自引:1,他引:12
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J Heinrich B Hoelscher M Wjst B Ritz J Cyrys H Wichmann 《Environmental health perspectives》1999,107(1):53-62
This cross-sectional epidemiological study collected health data for 2,470 school children between 5 and 14 years of age (89% of eligible children) who had lived most of their lives in either one of two counties strongly impacted by industrial pollution (Bitterfeld and Hettstedt) or in a neighboring county without any sources of industrial pollution (Zerbst). The objective of the study was to examine whether regional differences--with respect to the occurrence of childhood respiratory diseases and symptoms or allergies--exist and, if such differences are found, whether they persist when we adjust for the effects of known risk factors such as medical and sociodemographic factors or factors related to the indoor environment. Controlling for medical, sociodemographic, and indoor factors, according to parental reports, children residing in Hettstedt have about a 50% increased lifetime prevalence for physician-diagnosed allergies, eczema, and bronchitis compared to children from Zerbst and about twice the number of respiratory symptoms such as wheeze, shortness of breath, and cough without cold. Sensitization to common aeroallergens according to skin prick tests [odds ratio (OR) = 1.38; 95% confidence interval (CI), 1.02-1.86] and specific IgE levels (OR = 1.75; CI, 1.31-2.33) was more common for children from Hettstedt than children from the nonpolluted county. Bitterfeld children, on the other hand, more often received a diagnosis of asthma and eczema than children residing in Zerbst and also showed slightly increased sensitization rates. In conclusion, industrial pollution related to mining and smelting operations in the county of Hettstedt were associated with a higher lifetime prevalence of respiratory disorders and an increased rate of allergic sensitization in children between the ages of 5 and 14 years. Further studies are needed to determine what role the high dust content of heavy metals plays in Hettstedt. 相似文献
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