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排序方式: 共有832条查询结果,搜索用时 234 毫秒
41.
Michael V. Holmes Ruth Frikke-Schmidt Daniela Melis Robert Luben Folkert W. Asselbergs Jolanda M.A. Boer Jackie Cooper Jutta Palmen Pia Horvat Jorgen Engmann Ka-Wah Li N. Charlotte Onland-Moret Marten H. Hofker Meena Kumari Brendan J. Keating Jaroslav A. Hubacek Vera Adamkova Ruzena Kubinova Martin Bobak Kay-Tee Khaw Børge G. Nordestgaard Nick Wareham Steve E. Humphries Claudia Langenberg Anne Tybjaerg-Hansen Philippa J. Talmud 《Atherosclerosis》2014
Background
Conflicting evidence exists on whether smoking acts as an effect modifier of the association between APOE genotype and risk of coronary heart disease (CHD).Methods and results
We searched PubMed and EMBASE to June 11, 2013 for published studies reporting APOE genotype, smoking status and CHD events and added unpublished data from population cohorts. We tested for presence of effect modification by smoking status in the relationship between APOE genotype and risk of CHD using likelihood ratio test.In total 13 studies (including unpublished data from eight cohorts) with 10,134 CHD events in 130,004 individuals of European descent were identified. The odds ratio (OR) for CHD risk from APOE genotype (ε4 carriers versus non-carriers) was 1.06 (95% confidence interval (CI): 1.01, 1.12) and for smoking (present vs. past/never smokers) was OR 2.05 (95%CI: 1.95, 2.14). When the association between APOE genotype and CHD was stratified by smoking status, compared to non-ε4 carriers, ε4 carriers had an OR of 1.11 (95%CI: 1.02, 1.21) in 28,789 present smokers and an OR of 1.04 (95%CI 0.98, 1.10) in 101,215 previous/never smokers, with no evidence of effect modification (P-value for heterogeneity = 0.19). Analysis of pack years in individual participant data of >60,000 with adjustment for cardiovascular traits also failed to identify evidence of effect modification.Conclusions
In the largest analysis to date, we identified no evidence for effect modification by smoking status in the association between APOE genotype and risk of CHD. 相似文献42.
Carol J. Burns J. Michael Wright Jennifer B. Pierson Thomas F. Bateson Igor Burstyn Daniel A. Goldstein James E. Klaunig Thomas J. Luben Gary Mihlan Leonard Ritter A. Robert Schnatter J. Morel Symons Kun Don Yi 《Environmental health perspectives》2014,122(11):1160-1165
Background: There is a recognized need to improve the application of epidemiologic data in human health risk assessment especially for understanding and characterizing risks from environmental and occupational exposures. Although there is uncertainty associated with the results of most epidemiologic studies, techniques exist to characterize uncertainty that can be applied to improve weight-of-evidence evaluations and risk characterization efforts.Methods: This report derives from a Health and Environmental Sciences Institute (HESI) workshop held in Research Triangle Park, North Carolina, to discuss the utility of using epidemiologic data in risk assessments, including the use of advanced analytic methods to address sources of uncertainty. Epidemiologists, toxicologists, and risk assessors from academia, government, and industry convened to discuss uncertainty, exposure assessment, and application of analytic methods to address these challenges.Synthesis: Several recommendations emerged to help improve the utility of epidemiologic data in risk assessment. For example, improved characterization of uncertainty is needed to allow risk assessors to quantitatively assess potential sources of bias. Data are needed to facilitate this quantitative analysis, and interdisciplinary approaches will help ensure that sufficient information is collected for a thorough uncertainty evaluation. Advanced analytic methods and tools such as directed acyclic graphs (DAGs) and Bayesian statistical techniques can provide important insights and support interpretation of epidemiologic data.Conclusions: The discussions and recommendations from this workshop demonstrate that there are practical steps that the scientific community can adopt to strengthen epidemiologic data for decision making.Citation: Burns CJ, Wright JM, Pierson JB, Bateson TF, Burstyn I, Goldstein DA, Klaunig JE, Luben TJ, Mihlan G, Ritter L, Schnatter AR, Symons JM, Yi KD. 2014. Evaluating uncertainty to strengthen epidemiologic data for use in human health risk assessments. Environ Health Perspect 122:1160–1165; http://dx.doi.org/10.1289/ehp.1308062 相似文献
43.
Z Katsarava A Dzagnidze M Kukava E Mirvelashvili M Djibuti M Janelidze R Jensen LJ Stovner & TJ Steiner 《Cephalalgia : an international journal of headache》2009,29(9):949-952
We present a study of the general-population prevalence of cluster headache in the Republic of Georgia and discuss the advantages and challenges of different methodological approaches. In a community-based survey, specially trained medical residents visited 500 adjacent households in the capital city, Tbilisi, and 300 households in the eastern rural area of Kakheti. They interviewed all ( n = 1145) biologically unrelated adult occupants using a previously validated questionnaire. The household responses rates were 92% in Tbilisi and 100% in Kakheti. The survey identified 32 persons with possible cluster headache, who were then personally interviewed by one of two headache-experienced neurologists. Cluster headache was confirmed in one subject. The prevalence of cluster headache was therefore estimated to be 87/100 000 (95% confidence interval < 258/100 000). We used a conservative approach, which has an obvious advantage of high-quality data collection, but is very demanding of manpower and time. 相似文献
44.
Background
Whole body vibration (WBV) exposure at work is common and studies found evidence that this exposure might cause low back pain (LBP). A recent review concluded there is a lack of evidence of effective strategies to reduce WBV exposure. Most research in this field is focussed on the technical implications, although changing behaviour towards WBV exposure might be promising as well. Therefore, we developed an intervention programme to reduce WBV exposure in a population of drivers with the emphasis on a change in behaviour of driver and employer. The hypothesis is that an effective reduction in WBV exposure, in time, will lead to a reduction in LBP as WBV exposure is a proxy for an increased risk of LBP. 相似文献45.
Sala E Warren R McCann J Duffy S Luben R Day N 《International journal of epidemiology》2000,29(4):629-636
BACKGROUND: Mammographic parenchymal patterns are of particular interest because the denser patterns reduce screening sensitivity as well as increasing breast cancer risk, and because they have been shown to be affected by exogenous oestrogens. METHODS: We designed a case-control study comprising 200 cases with high-risk (P2 and DY) pattern and 200 controls with low-risk (N1 and P1) pattern. Mammograms were evaluated according to the Wolfe classification. RESULTS: Parity, body mass index (BMI) and current smoking were inversely and independently associated, whereas late age of menarche and history of benign breast disease were positively associated with high-risk mammographic patterns. Current-users of hormone replacement therapy (HRT) were more than twice as likely to have a high-risk pattern than never-users (OR = 2.48, 95% CI : 1.32-4.61). Women who used HRT for more than 5 years were almost three times more likely to have a high-risk pattern than never-users (OR = 2.77, 95% CI : 1.11-6.91). Relative to never-users, women who started HRT before the menopause were more than twice as likely to have a high-risk pattern (OR = 2.53, 95% CI : 1.31-4.87). CONCLUSIONS: Careful clinical and mammographical follow-up might be appropriate in women undergoing HRT. The HRT-induced mammographic pattern might be regarded as a new baseline and changes with respect to this new pattern could then be monitored over time. 相似文献
46.
MP Richardson TJ Williamson SW Lenton MJ Tarlow PT Rudd 《Archives of disease in childhood》1995,72(4):294-297
Transient evoked otoacoustic emissions (TEOAEs) are low amplitude sound waves produced by the healthy cochlea. They can be recorded with a microphone in the external ear. TEOAEs are abolished by hearing losses of 30 dB or more. The feasibility of using TEOAEs as a screening test for hearing loss in children was studied. TEOAE recordings were attempted in 56 children attending an audiology clinic. Recordings were possible from both ears in 52 children; of these 104 ears, 32 had hearing deficits of 30 dB or more. Hearing status was compared with the results of six TEOAE screening criteria. All criteria had a sensitivity of 1.00. Four standard TEOAE criteria yielded specificities of 0.46-0.58. Two new criteria derived from analysis of limited frequencies from the TEOAE waveform gave specificities of 0.76 and 0.82. It can be concluded that, when appropriate pass/fail criteria are employed, TEOAEs are a feasible screening test in children. 相似文献
47.
IJ Griffin TJ Cole KA Duncan AS Hollman MDC Donaldson 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(5):544-549
Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty. 相似文献
48.
Background
The Licensing Act 2003 (The Act) was implemented on the 24th November 2005 across England and Wales. The Act allowed more flexible and longer opening hours for licensed premises. We investigated the effect of The Act on alcohol related attendances to an inner city emergency department in Birmingham, UK. 相似文献49.
Wang WS; Fan FS; Hsieh RK; Chiou TJ; Lin JK; Lin TC; Yen CC; Liu JH; Hsu H; Chen PM 《Japanese journal of clinical oncology》1997,27(3):174-179
5-Fluorouracil in combination with leucovorin has been shown to be active
in therapeutic trials of metastatic colorectal carcinoma. In this study, we
administered these drugs to 72 patients with metastatic colorectal
carcinoma. Thirty-six of them without previous exposure to 5-fluorouracil
were treated with weekly bolus injections of 5-fluorouracil (425 mg/m2) and
leucovorin (25 mg/m2) supplemented with oral levamisole. Another 36
patients with or without prior 5-fluorouracil treatment received
5-fluorouracil 3,000 mg/m2 and leucovorin 300 mg/m2 in a 48-hour continuous
infusion every two weeks. Clinical efficacy and toxicity were assessed by
WHO criteria. Variables were tested for relations to response and survival
by univariate and multivariate analysis. The response rate was 19.4% in
weekly bolus arm and 13.9% in biweekly high-dose infusion arm (P = 0.527).
Median survivals in the two arms were 18.4 months (weekly) and 21 months
(biweekly) respectively (P = 0.708). Gastrointestinal side effects
including nausea, vomiting, diarrhea and mucositia were the major
toxicities of these regimens. By multivariate analysis, the only factor to
influence response rate was the site of metastases (P = 0.009). The only
factor to affect survival was performance status of the patient (P =
0.0001). We concluded that the two 5-fluorouracil based regimens are
well-tolerated and shown to have a response rate comparable with previous
reports of similar regimens in patients with metastatic colorectal cancer.
Only liver metastases seemed to have a better response to therapy.
Performance status is the most important prognostic factor in patients with
metastatic colorectal cancer.
相似文献
50.
Wang WS; Liu JH; Chiou TJ; Hsieh RK; Yen CC; Chen PM 《Japanese journal of clinical oncology》1997,27(3):180-184
A 28-year-old woman was admitted to our Hospital with a chief complaint of
progressive gingival swelling and loosening of teeth over about a year.
According to past history, she had received total thyroidectomy 2 years
previously due to thyromegaly. The thyroidectomy specimen was at first
interpreted as 'poorly differentiated carcinoma of the thyroid'. One year
ago, she began to be aware of gingival swelling and loosening of teeth. A
gum biopsy was taken and the pathologic features were similar to her
'thyroid carcinoma'. Subsequent investigations, including
immunohistochemical stain, showed the gum was heavily infiltrated with
histiocyte-like Langerhans' cells which were positive for S-100 protein.
Ultrastructural examination of the cells under electron microscope revealed
many typical intra-cytoplasmic Birbeck granules. Langerhans' cell
histiocytosis was diagnosed. Langerhans' cell histiocytosis with thyroid
involvement is extremely rare and may run a relatively indolent course.
Even on a retrospective examination, it may easily be confused with poorly
differentiated carcinoma of the thyroid. We suspect that this error may
have been made on other occasions and that the occurrence of this condition
may be underreported.
相似文献