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71.
Urmila P Kodavanti Carolyn F Moyer Allen D Ledbetter Mette C Schladweiler Daniel L Costa Russ Hauser David C Christiani Abraham Nyska 《Toxicological sciences》2003,71(2):237-245
Epidemiologists have associated particulate matter (PM) air pollution with cardiovascular morbidity and premature mortality worldwide. However, experimental evidence demonstrating causality and pathogenesis of particulate matter (PM)-induced cardiovascular damage has been insufficient. We hypothesized that protracted, repeated inhalation by rats of oil combustion-derived, fugitive emission PM (EPM), similar in metal composition to selected sources of urban air PM, causes exposure duration- and dose-dependent myocardial injury in susceptible rat strains. Zinc was the only primary water-leachable/bioavailable element of this EPM. Male Sprague-Dawley (SD), Wistar Kyoto (WKY), and spontaneously hypertensive (SH) rats were exposed nose-only to EPM (2, 5, or 10 mg/m(3), 6 h/day for 4 consecutive days or 10 mg/m(3), 6 h/day, 1 day/week for 4 or 16 consecutive weeks). Two days following the last EPM exposure, cardiac and pulmonary tissues were examined histologically. The results showed that particle-laden alveolar macrophages were the only pulmonary lesions observed in all three rat strains. However, WKY rats exposed to EPM (10 mg/m(3) 6 h/day, 1 day/week for 16 weeks) demonstrated cardiac lesions with inflammation and degeneration. To further characterize the nature of EPM-associated lesions, more rigorous histopathological and histochemical techniques were employed for WKY and SD rats. We examined the hearts for myocardial degeneration, inflammation, fibrosis, calcium deposits, apoptosis, and the presence of mast cells. Decreased numbers of granulated mast cells, and multifocal myocardial degeneration, chronic-active inflammation, and fibrosis were present in 5 of 6 WKY rats exposed to EPM for 16 weeks. None of these lesions were present in WKY exposed to clean air. EPM-related cardiac lesions were indistinguishable from air-exposed controls in SD and SH rats. This study demonstrates that long-term inhalation exposures to environmentally relevant PM containing bioavailable zinc can cause myocardial injury in sensitive rats. These findings provide supportive evidence for the epidemiological associations of cardiovascular morbidity and ambient PM. 相似文献
72.
73.
Elevated serum insulin-like growth factor binding protein-2 as a prognostic marker in patients with ovarian cancer. 总被引:3,自引:0,他引:3
Sally Baron-Hay Frances Boyle Alan Ferrier Carolyn Scott 《Clinical cancer research》2004,10(5):1796-1806
PURPOSE: The purpose of this research was to examine the diagnostic and prognostic significance of elevated serum insulin-like growth factor binding protein (IGFBP)-2 levels in women with ovarian cancer from diagnosis through treatment to relapse or remission. EXPERIMENTAL DESIGN: Serum collected pre- and postoperatively in women newly diagnosed with ovarian cancer, during adjuvant chemotherapy cycles, at 6 months follow-up and at relapse was analyzed for IGFBP-2. Control serum was from women undergoing pelvic or abdominal surgery for benign ovarian disease or nonovarian pathology. RESULTS: IGFBP-2 at diagnosis was significantly elevated (P < 0.0001) in women with ovarian cancer (887 +/- 62 ng/ml) compared with benign controls (337 +/- 25 ng/ml), and women undergoing nonovarian surgery (439 +/- 49 ng/ml) and correlated positively with tumor stage and cellular differentiation but not with CA125. Unexpectedly, IGFBP-2 levels increased additionally 1-week postoperatively in ovarian cancer patients (1581 +/- 90 ng/ml; P = 0.0027) as well as controls (977 +/- 95 ng/ml; P < 0.0001) and was higher in women who had suboptimal debulking compared with optimal debulking of their tumor. IGFBP-2 levels returned to normal in women without evidence of progressive disease, but remained significantly elevated in women who later relapsed. Patients with IGFBP-2 levels in the highest tertile at diagnosis had a significantly shorter progression-free interval and overall survival. CONCLUSION: In ovarian cancer IGFBP-2 is elevated at diagnosis, and corresponds to stage and histology with patients in the highest tertile of IGFBP-2 more likely to relapse and have a poorer outlook. Identification of these patients at diagnosis may allow more individualized, aggressive adjuvant treatment and follow-up, and IGFBP-2 may therefore be an important additional prognostic marker in this disease. 相似文献
74.
75.
Beverly Barton Rogers John Sommerauer Albert Quan Charles F. Timmons D. Brian Dawson Richard H. Scheuermann Karen Krisher Carolyn Atkins 《Pediatric and developmental pathology》1998,1(6):480-486
To assess whether the semiquantitative peripheral blood Epstein-Barr virus (EBV) polymerase chain reaction (PCR) test correlates
with post-transplant lymphoproliferative disorder (LPD), we compiled the results of the test done over a 3-year period ending
July 1997. Six hundred seventy-six tests were done on 185 patients. Four hundred-thirty tests (63%) were negative, 167 (25%)
were weak positive, 67 (10%) were moderate positive, and 12 (2%) were strong positive. Twelve of the patients developed a
lymphoproliferative disorder (LPD) during this time. The EBV PCR tests proximate to the diagnosis of LPD in the 12 patients
with EBV-positive LPD were 6 strong positive, 5 moderate positive, 1 weak positive. No patient with LPD had a negative result
at diagnosis. Stated another way, 6/12 (50%) of strong-positive PCR tests, 5/67 (7%) moderate-positive tests, and 1/167 (.6%)
of weak-positive tests correlated with LPD. Serologic evaluation for EBV done on 7 patients at the time of LPD showed low
serologic responses in 5 of the 7 patients. The EBV PCR temporally associated with the serology indicated moderate to large
viral burdens. In each patient evaluated serially, the EBV PCR test rose before the diagnosis of LPD and fell with treatment
for the disorder. In conclusion, the EBV PCR test may be used as an adjunct to the diagnosis of patients with LPD and may
be used to monitor response to therapy for the disorder.
Received August 26, 1997; accepted January 13, 1998. 相似文献
76.
Randomised controlled trial of advice on an egg exclusion diet in young children with atopic eczema and sensitivity to eggs 总被引:2,自引:0,他引:2
Rosemary Lever Carolyn MacDonald Pauline Waugh Tom Aitchison 《Pediatric allergy and immunology》1998,9(1):13-19
Background: The role of exclusion diets in the management of atopic eczema in young children is uncertain. This randomised controlled trial evaluates the effect of excluding egg from the diet in young children with atopic eczema and sensitivity to eggs. Fifty-five such children were randomised either to a 4-week regimen, in which mothers were given general advice on care of eczema and additional specific advice from a dietician about an egg exclusion diet (diet group), or to a control group in which general advice only was given. Both groups continued conventional topical treatment. Disease activity was assessed by estimates of the surface area affected by eczema and by an arbitrary severity score. Possible egg sensitivity was identified by RAST before randomisation and after the trial by double-blind placebo-controlled egg challenge. Results: The mean reduction in surface area affected by eczema was significantly greater (p = 0.02) in the group receiving dietary advice (from 19.6% to 10.9% area affected) than in the control group (from 21.9% to 18.9%). A significant improvement also occurred in severity score (p=0.04): from 33.9 to 24.0 units for the diet group compared with a decrease from 36.7 to 33.5 in the control group. The study suggests that advice on the dietary exclusion of eggs is useful as part of the overall management of young children with atopic eczema and sensitivity to eggs. 相似文献
77.
Carolyn R. Freeman B.S. M.B. FRCP Jean-Pierre Farmer M.D. FRCS José. Montes M.D. 《International journal of radiation oncology, biology, physics》1998,41(5):283-987
Developments in imaging and in neurosurgical techniques over the past decade have substantially altered the management of children with low-grade astrocytoma. Indications for surgery have become more clearly defined, and a larger proportion of children undergo complete or subtotal resection than in the past. Fewer receive adjuvant therapy, even though the options in this regard are more numerous now and theoretically likely to result in less morbidity than conventional external beam radiotherapy.
This review will address in particular the correlations between location, imaging appearance, and behavior that need to be more widely appreciated, and present recommendations regarding the management of these tumors. 相似文献
78.
79.
Krithika Rajagopalan PhD Linda Abetz MA Polyxane Mertzanis MPH Derek Espindle MA Carolyn Begley OD MS Robin Chalmers OD Barbara Caffery OD MS Christopher Snyder OD MS J. Daniel Nelson MD Trefford Simpson PhD Timothy Edrington OD MS 《Value in health》2005,8(2):168-174
OBJECTIVE: The purpose of this study was to compare the discriminative properties of two generic health-related quality of life (QoL) instruments (SF-36 and EQ-5D) and a newly developed disease-specific patient-reported outcomes instrument (Impact of Dry Eye on Everyday Life (IDEEL)) to distinguish between different levels of dry eye severity. METHODS: Assessment of 210 people: 130 with non-Sjogren's Keratoconjunctivitis Sicca (non-SS KCS), 32 with Sj?gren's Syndrome (SS) and 48 controls; comparison of SF-36, EQ-5D, and IDEEL age-adjusted data by dry eye severity levels. Severity was assessed based on diagnosis (non-SS KCS, SS, control), patient-report (none, very mild, mild, moderate, severe, extremely severe) and clinician-report (none, mild, moderate, severe). RESULTS: Discriminative validity results were consistent for all instruments. Significant differences between severity levels were found with most SF-36 scales (P < 0.05), all EQ-5D scales (P < 0.05), and all IDEEL scales (P < 0.0001), except for Treatment Satisfaction. IDEEL scales consistently outperformed the generic QoL measures regardless of the severity criterion used. Most SF-36 scales outperformed the EQ-5D QoL scale, but the EQ-5D visual analog scale outperformed the SF-36 scales, except for General Health Perceptions. CONCLUSIONS: The disease-specific IDEEL scales are better able to discriminate between severity levels than the majority of the generic QoL scales. Preliminary evidence demonstrates that the IDEEL will be sensitive to QoL changes over time, although further testing in controlled longitudinal studies is needed. 相似文献
80.
Peter Spurgeon Carolyn Hicks Stephen Field Fred Barwell 《Health services management research》2005,18(2):75-85
BACKGROUND: In February 2003, a new General Practitioner (GP) contract was agreed between the profession's leaders and the government, which was later accepted following a national ballot of GPs. However, the ballot simply required respondents to vote for or against the proposal; it did not provide any opportunity to identify which aspects of the new contract were more or less acceptable. Since the proposed changes were far reaching, the implications of implementing and managing these were considerable. Consequently, some information about how GPs viewed various components of the new contract would enable a more targeted and effective management strategy to be developed that would facilitate the introduction of all aspects of the contract. OBJECTIVES: To survey GPs working within the West Midlands region regarding their opinions on each of the key features of the new contract. METHOD: A postal survey of 360 GPs was undertaken, using a specially devised questionnaire. RESULTS: Four factors emerged as the most acceptable aspects of the contract: option to opt out of out-of-hours work, flexibility in the services provided, prediction of future income levels and linking practice to performance targets. Least acceptable were: performance monitoring systems, the new financial formula for calculating income, greater patient involvement in service development and 24/48 hour access. With regard to potential outcomes of the contract, the most positive were considered to be increased proportion of salaried GPs, increased salaries, appropriate quality standards for care, earlier retirement; the factors least likely to be of potential benefit were: reduction in occupational stress, simplification of the regulatory framework, improved equity of workload and improved staff retention. Further analysis of the results using inferential statistics revealed a range of subgroup differences in reaction to the contract. CONCLUSION: Overall, those aspects of the new contract that are perceived to reduce workload and enhance salary were supported, while those that increase targets and bureaucracy were not. Generally, there was only moderate support for the changes, which could be explained by a general scepticism about any top-down modifications, the practicality and power of the changes to impact upon practice and/or a genuine belief that the modifications are unacceptable. Taken together, these results provide an indicative focus for managing the implementation of the new contract, especially with regard to its least acceptable components and the emerging differences between subgroups of GPs. 相似文献