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131.
Larsson J Persson C Tengvall P Lundqvist-Gustafsson H 《Journal of biomedical materials research. Part A》2004,68(3):448-457
Polymorphonuclear neutrophils (PMN) are among the first inflammatory cells to arrive at an implant interface, where they encounter with the foreign material and may produce reactive oxygen species (ROS). During the interaction between titanium and ROS, titanium-peroxy (Ti-peroxy) compounds may be formed. We used a Ti-peroxy gel, made from titanium and hydrogen peroxide, to study the effects of Ti-peroxy compounds on PMN. In the absence of serum, the Ti-peroxy gel decreased the oxidative response of PMN to yeast and PMA and reduced PMN apoptosis without inducing necrosis. These effects could not be ascribed to the release of hydrogen peroxide from the Ti-peroxy gel, because a steady-state hydrogen peroxide producing system failed to mimic the effects of the gel. The effects were similarly unaffected when PMN were preincubated with beta(2)-integrin antibodies, questioning the involvement of adhesion molecules. Nevertheless, when a filter was used to separate the Ti-peroxy gel from the cells, the gel effect on PMN life span was abolished, pointing to a contact-dependent mechanism. In the presence of serum, the Ti-peroxy gel had no effect on the PMN oxidative response and life span, but appeared rather inert. In summary, this study demonstrates that the Ti-peroxy gel has potentially anti-inflammatory properties through a combined peroxide and physical contact effect, supporting the notion that interactions between titanium and inflammatory cells are responsible for the good performance of titanium in vivo. 相似文献
132.
Large-scale molecular and tissue microarray analysis of mesothelin expression in common human carcinomas 总被引:10,自引:0,他引:10
Frierson HF Moskaluk CA Powell SM Zhang H Cerilli LA Stoler MH Cathro H Hampton GM 《Human pathology》2003,34(6):605-609
The 40-kilodalton processed glycoprotein, mesothelin, is highly expressed in epithelial mesotheliomas and adenocarcinomas of the ovary (serous papillary) and pancreas, but its expression in a large series of other common carcinomas has not been completely explored. In the present study, we used oligonucleotide and tissue microarrays to profile the expression of the mesothelin gene (MSLN) and encoded protein, respectively. Among 150 carcinomas of multiple anatomic sites, we found the highest average expression of MSLN in serous carcinomas of the ovary and adenocarcinomas of the pancreas, consistent with previous reports, as well as measurable but less-striking expression in pulmonary, gastric/esophageal, and colorectal adenocarcinomas. On tissue microarrays containing 621 carcinomas derived from the same and additional sites as those profiled by gene expression, mesothelin immunoreactivity was highest in cancers of the ovary (serous papillary, endometrioid, and undifferentiated) and pancreas, with less frequent staining seen in adenocarcinomas of the endometrium, lung, and stomach/esophagus. Some immunopositivity was observed in 42% of pulmonary adenocarcinomas, including 18% that had >50% of tumor cells that were immunoreactive. Some 14% of breast and 30% of colorectal adenocarcinomas showed immunopositivity, but no case contained >50% tumor cells that were immunoreactive. Mesothelin was either entirely absent or present in <5% of carcinomas of the prostate, bladder/ureter, liver, kidney, and thyroid. Overall, we observed good concordance between the results obtained by oligonucleotide and tissue microarrays. This large study of the MSLN gene and protein expression in common carcinomas provides data for future investigations that evaluate the utility of mesothelin/megakaryocyte potentiating factor as a potential serum tumor marker or target of immunotoxin-based therapy in human cancers. 相似文献
133.
134.
Detection of somatic mutations in man: evaluation of the microtitre cloning assay for T-lymphocytes 总被引:3,自引:0,他引:3
Henderson Leigh; Cole Helen; Cole Jane; James S. Elizabeth; Green Michael 《Mutagenesis》1986,1(3):195-200
A method of detecting 6-thioguanine-resistant lymphocytes bythe cloning of T-lymphocytes in microtitre wells is evaluatedfor its usefulness in population monitoring. Factors shown toaffect the cloning efficiency of lymphocytes include the strainand irradiation level of the lymphoblastoid feeder cells andthe use of a pre-incubation period in bulk culture without mitogenicstimulus before plating at limiting dilutions. Cord blood sampleshave markedly lower mutant frequencies than adult blood samples.The adult range was 8.0 x 107 to 1.8 x 105. Sevenmales and seven females aged between 23 and 47 years were sampled.No effect of sex or age was found. Individual samples whichwere divided at collection and treated separately did not varyfrom each other, but repeat samples taken at different timesshowd up to a 2-fold variation. The application of this methodin population monitoring is discussed. 相似文献
135.
Influence of cutaneous sensitization with oxazolone on recruitment of myelogenous stem cells in the thymus 下载免费PDF全文
Cutaneous sensitization of CBA mice with oxazolone was followed 3 days later by increased cell proliferation in the regional lymph nodes and spleen, as measured by incorporation of radiolabelled 5-iodo-2'-deoxyuridine. The thymus was reduced in weight and contained fewer proliferating cells. Other mice were part-body irradiated, with shielding of the anterior three-quarters of the body, and injected with CBA-T6T6 bone marrow cells. Half of them were subsequently sensitized with oxazolone. The frequency of dividing cells of bone marrow origin in the thymus of sensitized and control animals was estimated cytologically 3–70 days later. There was a significant tendency for sensitized mice to have more dividing cells of donor origin in the thymus than controls. 相似文献
136.
Helen G. Morris M.D. Ittai Neuman M.D. Elliot F. Ellis M.D. 《The Journal of allergy and clinical immunology》1974,54(6):350-358
Plasma steroid concentrations were measured in asthmatic children 24 and 48 hours after administration of alternate-day treatment with prednisone, and the results were compared with those of control patients who did not receive corticosteroid treatment as well as those of patients who were treated with prednisone each day. It was found that 24 hours after administration of prednisone in any dose, plasma steroid concentrations were significantly lower than those of the control group. The degree of suppression in plasma steroid concentration was less marked in patients who received treatment on alternate days than in those who received the same doses of prednisone each day. Within 48 hours after administration of alternate-day treatment, plasma steroid concentrations approached the values observed in the control group and were independent of the magnitude of the prednisone dose. Although alternateday steroid treatment was associated with transient and incomplete suppression of pituitary-adrenal function, patients whose therapy was changed from a daily to an alternate-day regimen sometimes exhibited prolonged suppression of adrenal cortical function. 相似文献
137.
Monitoring seizure length is an important addition to the clinical practice of ECT. Without monitoring, undetected missed seizures may occur. In a retrospective study of ECT treatments for a sample of 58 patients with a DSM-III diagnosis of major depression, significantly more missed seizures (p < 0.05) occurred in the elderly males. 相似文献
138.
Until last year only two U.S. manufacturers were producing ECT machines for purchase. These machines differed in waveforms: a sine-wave device (Medcraft Corp.) and a brief-pulse bidirectional square-wave machine (MECTA Corp.). Early in 1985 a new brief-pulse bidirectional square-wave machine called the Thymatron was marketed (Somatics Inc.). For the first time this created a choice in brief-pulse equipment available in the U.S. This paper summarizes our initial impressions to this new brief-pulse device and one of MECTA's most recent brief-pulse models (SR-1) in terms of features, safety, practicality, and cost. 相似文献
139.
Improving health care for disabled people in COVID-19 and beyond: Lessons from Australia and England
Anne Kavanagh Helen Dickinson Gemma Carey Gwynnyth Llewellyn Eric Emerson George Disney Chris Hatton 《Disability and health journal》2021,14(2):101050
COVID-19 has exacerbated pre-existing difficulties children and adults with disability face accessing quality health care. Some people with disability are at greater risk of contracting COVID-19 because they require support for personal care and are unable to physically distance, e.g. those living in congregate settings. Additionally, some people with disability have health conditions that put them at higher risk of poor outcomes if they become infected. Despite this, governments have been slow to recognise, and respond to, the unique and diverse health care needs of people with disability during COVID-19. While some countries, including Australia, have improved access to high-quality health care for people with disability others, like England, have failed to support their citizens with disability. In this Commentary we describe the health care responses of England and Australia and make recommendations for rapidly improving health care for people with disability in the pandemic and beyond. 相似文献
140.
Louise Capling Ryan Tam Kathryn L. Beck Gary J. Slater Victoria M. Flood Helen T. OConnor Janelle A. Gifford 《Nutrients》2021,13(1)
While athletes’ nutrient intakes have been widely reported, few studies have assessed the diet quality of athletes. This is the first study to evaluate the diet quality of athletes using the purpose-built Athlete Diet Index (ADI). A convenience sample of 165 elite athletes from Australian sporting institutions completed the ADI online, with subsequent automated results provided to their respective accredited sports dietitians (ASDs). At the completion of athlete participation, ASDs (n = 12) responded to a range of survey items using a Likert scale (i.e., 1 = strongly agree to 5 = strongly disagree) to determine the suitability of the ADI in practice. Differences in ADI scores for demographics and sport-specific variables were investigated using independent t-tests, analysis of variance (ANOVA) and Bonferroni multiple comparisons. Spearman’s rank correlation was used to assess the association between total scores and demographics. The mean total ADI score was 91.4 ± 12.2 (range 53–117, out of a possible 125). While there was no difference in total scores based on demographics or sport-specific variables; team sport athletes scored higher than individual sport athletes (92.7 vs. 88.5, p < 0.05). Athletes training fewer hours (i.e., 0–11 h/week) scored higher on Dietary Habits sub-scores compared with athletes training more hours (≥12 h/week; p < 0.05), suggesting that athletes who train longer may be at risk of a compromised dietary pattern or less than optimal nutrition practices that support training. Most (75%) ASDs surveyed strongly agreed with the perceived utility of the ADI for screening athletes and identifying areas for nutrition support, confirming its suitability for use in practice. 相似文献