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排序方式: 共有849条查询结果,搜索用时 10 毫秒
11.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
12.
Induction of a differentiated ciliated cell phenotype in primary cultures of Fallopian tube epithelium 总被引:5,自引:1,他引:5
Human Fallopian tubal epithelial cells in culture lose morphological
features associated with the epithelium in situ and the extent to which
they retain their in-vivo phenotype or function is unknown. In order to
address this question, immunocytochemical markers were identified which
distinguish secretory (HMFG2+, LhS28-) from ciliated (HMFG2-, LhS28+)
epithelial cells in tissue sections of Fallopian tube. These markers were
used to analyse the phenotype of tubal cells in vitro. Primary cultures of
human tubal epithelial cells were seeded onto glass and grown to confluence
before addition of oestradiol-17beta. In the absence of hormone, tubal
epithelial cells expressed cytokeratins and nuclear receptors for oestrogen
and progesterone and adopted a homogeneous (HMFG2+, LhS28-) secretory cell
phenotype. Following the addition of oestradiol-17beta, a proportion of
cells became positive for LhS28. The induction of a ciliated epithelial
cell phenotype was confirmed by scanning electron microscopy, where on
permeable collagen membranes, approximately one-third of tubal epithelial
cells became ciliated in the presence of oestradiol-17beta. We suggest that
in vitro, tubal epithelial cells adopt an immature secretory-like phenotype
and that oestrogen can induce differentiation to a ciliated epithelial cell
phenotype.
相似文献
13.
K Suzuki T Ezoe J Tohyama J Matsuda MT Vanier K Suzuki 《Acta paediatrica (Oslo, Norway : 1992)》2003,92(S443):54-62
Spontaneously occurring genetic lysosomal storage diseases are as rare in other mammalian species as in man. However, the advent of gene targeting technology has revolutionized the state of animal models of genetic diseases. Nearly all lysosomal storage diseases known in man have been duplicated in the mouse. The technology now allows, not only complete inactivation of endogenous genes, but also the introduction of essentially any type of mutation. These animal models can overcome many of the limitations inherent in studies of human patients - rarity of the disease, extremely complex genetic background and logistical and ethical constraints in the design and execution of experiments with human subjects. For example, genetic manipulations of germ cells or cross-breeding experiments between two mutants are readily feasible with animal models. Two major areas of the utility of animal models are the clarification of the pathophysiology/pathogenetic mechanism of disease and the exploration of therapeutic approaches. Examples of experiments using animal models of lysosomal storage disease are presented, primarily from studies undertaken in our own laboratory.
Conclusion : Animal models have proved invaluable in extending our knowledge of the lysosomal storage diseases and exploring potential therapies. 相似文献
Conclusion : Animal models have proved invaluable in extending our knowledge of the lysosomal storage diseases and exploring potential therapies. 相似文献
14.
Postoperative deep wound infection in adults after posterior lumbosacral spine fusion with instrumentation: incidence and management 总被引:5,自引:0,他引:5
Picada R Winter RB Lonstein JE Denis F Pinto MR Smith MD Perra JH 《Journal of spinal disorders》2000,13(1):42-45
The authors reviewed 817 instrumented lumbosacral fusions in adults and found an incidence of 3.2% deep wound infections. The primary focus of this study was the management of these infections, with particular attention to whether the implants needed to be removed. A consulting infectious disease specialist indicated that an acute infection of a low back fusion wound could not be healed without removal of the metallic implants. This opinion was in contrast to the authors' daily experience and prompted this study. The authors identified and reviewed 817 cases of instrumented posterior lumbosacral arthrodeses in adults. A detailed analysis of any case with a deep wound infection was performed and yielded and infection rate of 3.2% (26 patients). Of these, 24 achieved a clean, closed wound without removal of instrumentation through a protocol of aggressive debridement and secondary closure. Instrumentation removal is not necessary to obtain a clean, closed wound using an aggressive approach with early diagnosis, vigorous debridement in the operative room under general anesthesia, delayed primary or secondary closure, and appropriate antibiotic coverage. 相似文献
15.
Hemoglobin and albumin adducts of benzene oxide among workers exposed to high levels of benzene 总被引:3,自引:0,他引:3
Yeowell-O'Connell K; Rothman N; Smith MT; Hayes RB; Li G; Waidyanatha S; Dosemeci M; Zhang L; Yin S; Titenko-Holland N; Rappaport SM 《Carcinogenesis》1998,19(9):1565-1571
Benzene oxide (BO) reacts with cysteinyl residues in hemoglobin (Hb) and
albumin (Alb) to form protein adducts (BO-Hb and BO-Alb), which are
presumed to be specific biomarkers of exposure to benzene. We analyzed
BO-Hb in 43 exposed workers and 42 unexposed controls, and BO-Alb in a
subsample consisting of 19 workers and 19 controls from Shanghai, China, as
part of a larger cross-sectional study of benzene biomarkers. The adducts
were analyzed by gas chromatography-mass spectrometry following reaction of
the protein with trifluoroacetic anhydride and methanesulfonic acid. When
subjects were divided into controls (n = 42) and workers exposed to < or
=31 (n = 21) and >31 p.p.m. (n = 22) benzene, median BO-Hb levels were
32.0, 46.7 and 129 pmol/g globin, respectively (correlation with exposure:
Spearman r = 0.67, P < 0.0001). To our knowledge, these results
represent the first observation in humans that BO-Hb levels are
significantly correlated with benzene exposure. Median BO-Alb levels in
these 3 groups were 103 (n = 19), 351 (n = 7) and 2010 (n = 12) pmol/g Alb,
respectively, also reflecting a significant correlation with exposure
(Spearman r = 0.90, P < 0.0001). The blood dose of BO predicted from
both Hb and Alb adducts was very similar. These results clearly affirm the
use of both Hb and Alb adducts of BO as biomarkers of exposure to high
levels of benzene. As part of our investigation of the background levels of
BO-Hb and BO-Alb found in unexposed persons, we analyzed recombinant human
Hb and Alb for BO adducts. Significant levels of both BO-Hb (19.7 pmol/g)
and BO-Alb (41.9 pmol/g) were detected, suggesting that portions of the
observed background adducts reflect an artifact of the assay, while other
portions are indicative of either unknown exposures or endogenous
production of adducts.
相似文献
16.
Increased aneusomy and long arm deletion of chromosomes 5 and 7 in the lymphocytes of Chinese workers exposed to benzene 总被引:4,自引:1,他引:4
Zhang L; Rothman N; Wang Y; Hayes RB; Li G; Dosemeci M; Yin S; Kolachana P; Titenko-Holland N; Smith MT 《Carcinogenesis》1998,19(11):1955-1961
Two of the most common cytogenetic changes in therapy- and chemical-
related leukemia are the loss and long (q) arm deletion of chromosomes 5
and 7. The detection of these aberrations in lymphocytes of individuals
exposed to potential leukemogens may serve as useful biomarkers of
increased leukemia risk. We have used a novel fluorescence in situ
hybridization (FISH) procedure to determine if specific aberrations in
chromosomes 1, 5 and 7 occur at an elevated rate in the blood cells of
workers exposed to benzene. Forty-three healthy workers exposed to a wide
range of benzene concentrations (median 31 p.p.m., 8 h time-weighted
average) and 44 unexposed controls from Shanghai were studied. Whole blood
was cultured and metaphase spreads were harvested at 72 h. Benzene exposure
was associated with increases in the rates of monosomy 5 and 7 but not
monosomy 1 (P < 0.001, P < 0.0001 and P = 0.94, respectively) and
with increases in trisomy and tetrasomy frequencies of all three
chromosomes. Long arm deletion of chromosomes 5 and 7 was increased in a
dose-dependent fashion (P = 0.014 and P < 0.0001) up to 3.5-fold in the
exposed workers. These results demonstrate that leukemia-specific changes
in chromosomes 5 and 7 can be detected by FISH in the peripheral blood of
otherwise healthy benzene-exposed workers. We suggest that aberrations in
chromosomes 5 and 7 may be useful biomarkers of early biological effect for
benzene exposure.
相似文献
17.
Wesley H. Self MD MPH Joyce Mickanin MSN RN Carlos G. Grijalva MD MPH Freda H. Grant MT ASCP Michelle C. Henderson MSN RN Glenda Corley MT ASCP D. Glen Blaschke II MD Candace D. McNaughton MD MPH Tyler W. Barrett MD MSCI Thomas R. Talbot MD MPH Barbara R. Paul MD 《Academic emergency medicine》2014,21(3):274-282
18.
19.
Gregory Welter PE BCEE Myra Socher BS EMT/P Patricia Needham MT HEM Steve Bieber MS MPA Heidi Bonnaffon MS 《Journal of healthcare risk management》2013,32(4):5-14
The purpose of this article is to outline the criticality of water supply in sustained operations of healthcare facilities, particularly during community emergencies, and to advocate for enhanced cross‐sector support from the water utilities in meeting this need. Information and ideas presented here were developed in the course of a regional project sponsored by the Metropolitan Washington Council of Governments (MWCOG) for development of emergency water supply operations plans for critical water uses in the Washington, DC, area. 相似文献
20.
Francesco Venturelli Giuliano Carrozzi Letizia Sampaolo Lara Bolognesi Sandro Baldissera Nicoletta Bertozzi Stefano Campostrini Benedetta Contoli Gianluigi Ferrante Maria Masocco Valentina Minardi Angelo D'Argenzio Pirous F Moghadam Luana Penna Alberto Perra Elisa Quarchioni Mauro Ramigni Massimo O Trinito Stefania Salmaso 《Lancet》2014
BackgroundInfluenza is an important public health problem, with potential severe consequences among people with chronic diseases. The aim of this study was to obtain reliable measures of seasonal influenza vaccine uptake in this population, otherwise not available in Italy.MethodsProgressi delle Aziende Sanitarie per la Salute in Italia (PASSI) is a nationwide surveillance system of health-related behaviours and acceptance of preventive interventions (including influenza immunisation) offered by the Italian National Health Service. Data are collected with telephone interviews at local health unit level for supporting local activities. The survey sample is randomly selected from local health unit lists of adult residents. The trend of annual vaccine coverage since 2008 was estimated for people aged 18–64 years who reported having at least one chronic disease. To obtain a sufficient sample size in subgroups, we analysed the characteristics of vaccinated people in the 2010–13 cumulative dataset. Univariate, multivariate, and logistic regression analyses were undertaken.FindingsIn 2008–13, 13 659 individuals with at least one chronic disease were interviewed. Vaccination coverage fell significantly from 29·7% (95% CI 27·2–32·4) in 2007–08 to 19·9% (18·0–22·1) in 2012–13. During 2010–13, the overall proportion of vaccinated people with a chronic disease was 25·6% (24·5–26·7). Vaccine coverage of people with diabetes (34·3%, 31·7–36·9) or cardiovascular diseases (31·8%, 29·6–34·2) was greater than that of people affected by renal failure, respiratory diseases, tumours, or chronic liver diseases (26·5% [22·5–30·7], 24·9% [23·2–26·7], 22·2% [20·0–24·6], and 20·6% [17·5–24·6], respectively). Vaccination coverage increased with age (from 13·1% [11·0–15·5] in the 18–34 year age group to 33·4% [31·9–35·1] in people aged 50–64 years); it was higher among people with a low educational level than among those with a high educational level, higher in those having economic difficulties than in those with no economic difficulties, and higher among Italian citizens than among non-citizens.InterpretationIn the past few years, prevalence of influenza vaccination in Italian adults with at least one chronic disease was well below the Ministry of Health's goal (75% minimum) and showed a downward trend. A major reason of this evolution is probably the changing public perception of the benefits and risks of vaccines. PASSI is a source of useful data not otherwise available for public health intervention.FundingItalian Ministry of Health. 相似文献