全文获取类型
收费全文 | 100篇 |
免费 | 12篇 |
出版年
2022年 | 2篇 |
2019年 | 2篇 |
2016年 | 4篇 |
2015年 | 7篇 |
2014年 | 7篇 |
2013年 | 6篇 |
2012年 | 6篇 |
2011年 | 4篇 |
2010年 | 4篇 |
2009年 | 2篇 |
2008年 | 5篇 |
2007年 | 12篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 4篇 |
2003年 | 3篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1984年 | 2篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
2.
David Bellinger Herbert L. Needleman Richard Bromfield Maureen Mintz 《Biological trace element research》1984,6(3):207-223
To investigate the impact of low-level lead exposure on children's behavior within a natural setting, we assessed the school performance of a sample of 141 elementary school children classified according to dentine lead level. Twenty-two children had “elevated” levels (≥20 parts per million), 71 had “midrange” levels (10.0–19.9 parts per million), and 48 had “low” levels (<10 parts per million). Four types of outcome data were collected: (1) scores on a standardized group intelligence test, (2) teachers' ratings, (3) incidence of academic failure (assignment to remedial aid, grade retention), and (4) observations of classroom behavior. In general, higher dentine lead levels were associated with less favorable school performance, with most covariance-adjustedp-values in the range of 0.05–0.15. The incidence of grade retention was the outcome most strongly related to lead level. The pattern of results suggests a consistent, though weak relationship between children's dentine lead levels and elementary school performance. 相似文献
3.
4.
DC Chhieng AR Frost S Niwas H Weiss WE Grizzle S Beeken 《Biotechnic & histochemistry》2013,88(1):25-36
Small biopsy samples are used increasingly to assess the biomarker expression for prognostic information and for monitoring therapeutic responses prior to and during neoadjuvant therapy. The issue of intratumor heterogeneity of expression of biomarkers, however, has raised questions about the validity of the assessment of biomarker expression based on limited tissue samples. We examined immunohistochemically the expression of HER-2neu (p185erbB-2), epidermal growth factor receptor (EGFR), Bcl-2, p53, and proliferating cell nuclear antigen (PCNA) in 30 breast carcinomas using archived, paraffin embedded tissue and determined the extent of intratumor heterogeneity. Each section was divided into four randomly oriented discrete regions, each containing a portion of the infiltrating carcinoma. For each tumor, the entire lesion and four regions were analyzed for the expression of these markers. Scores of both membrane and cytoplasmic staining of HER-2neu and EGFR, scores of cytoplasmic staining of Bcl-2, and scores of nuclear staining of both p53 and PCNA were recorded. The intensity of staining and the proportion of immunostained cells were determined. A semiquantitative immunoscore was calculated by determining the sum of the products of the intensity and corresponding proportion of stained tumor cells. We analyzed both invasive (IDC) and in situ (DCIS) carcinomas. The Wilcoxon signed-rank test was used for paired comparisons between overall and regional immunoscores and between overall and regional percentages of stained cells. Spearman's correlation coefficients were used to assess the level of agreement of overall biomarker expression with each of the regions. Generalized linear models were used to assess overall and pair-wise differences in the absolute values of percent changes between overall and regional expression of biomarkers. For IDCs, there were no statistically significant differences in the expression of the biomarkers in terms of either the percentage of cells staining or the immunoscores when comparing the entire tumor with each region except for the lower EGFR expression of arbitrarily selected region 1 and lower p53 expression of region 1 compared to that of the entire tumor section. For DCIS, there were no statistically significant differences in the expression of the biomarkers between the entire tumor and each region except in PCNA of region 2 compared to that of entire tumor section. Positive correlation of immunoscores was observed between the entire tumor and each region as well as across all four regions for IDC. Similar observations were noted with DCIS except for HER-2neu and PCNA. No statistically significant differences were observed in the absolute values of percent changes of biomarker expression between overall and the four regions for both DCIS and IDC. Therefore, no significant intratumor heterogeneity in the expression of HER-2neu, Bcl-2, and PCNA was observed in IDC. Minor regional variations were observed for EGFR and p53 in IDC. Similarly, no significant regional variation in the expression of markers was observed in DCIS except for PCNA. 相似文献
5.
Brooke M. Emerling Jonathan B. Hurov George Poulogiannis Kazumi S. Tsukazawa Rayman Choo-Wing Gerburg M. Wulf Eric L. Bell Hye-Seok Shim Katja A. Lamia Lucia E. Rameh Gary Bellinger Atsuo T. Sasaki John M. Asara Xin Yuan Andrea Bullock Gina M. DeNicola Jiaxi Song Victoria Brown Sabina Signoretti Lewis C. Cantley 《Cell》2013
6.
7.
Brecht Devleesschauwer Juanita A. Haagsma Frederick J. Angulo David C. Bellinger Dana Cole D?rte D?pfer Aamir Fazil Eric M. Fèvre Herman J. Gibb Tine Hald Martyn D. Kirk Robin J. Lake Charline Maertens de Noordhout Colin D. Mathers Scott A. McDonald Sara M. Pires Niko Speybroeck M. Kate Thomas Paul R. Torgerson Felicia Wu Arie H. Havelaar Nicolas Praet 《PloS one》2015,10(12)
Background
The Foodborne Disease Burden Epidemiology Reference Group (FERG) was established in 2007 by the World Health Organization to estimate the global burden of foodborne diseases (FBDs). This paper describes the methodological framework developed by FERG''s Computational Task Force to transform epidemiological information into FBD burden estimates.Methods and Findings
The global and regional burden of 31 FBDs was quantified, along with limited estimates for 5 other FBDs, using Disability-Adjusted Life Years in a hazard- and incidence-based approach. To accomplish this task, the following workflow was defined: outline of disease models and collection of epidemiological data; design and completion of a database template; development of an imputation model; identification of disability weights; probabilistic burden assessment; and estimating the proportion of the disease burden by each hazard that is attributable to exposure by food (i.e., source attribution). All computations were performed in R and the different functions were compiled in the R package ''FERG''. Traceability and transparency were ensured by sharing results and methods in an interactive way with all FERG members throughout the process.Conclusions
We developed a comprehensive framework for estimating the global burden of FBDs, in which methodological simplicity and transparency were key elements. All the tools developed have been made available and can be translated into a user-friendly national toolkit for studying and monitoring food safety at the local level. 相似文献8.
9.
John W. Chapman James T. Carlton M. Renee Bellinger April M. H. Blakeslee 《Biological invasions》2007,9(8):995-1008
The closely documented spread of the European periwinkle snail, Littorina littorea from Pictou, Nova Scotia in 1840 to New Jersey by 1870, its near absence in pre-European fossil deposits, and its close association
with human mechanisms of transport from Europe, are among the clearest evidence of a human-mediated marine introduction ever
reported. Genetic data were recently proposed as evidence that North American L. littorea predate European contact and thus, are not introduced. Review of these genetic data and all other data reveals that the simplest
explanation of the modern occurrence of this snail in North America is by human introduction. 相似文献
10.
Shalindra Ranasinghe Renu Wickremasinghe Sanjeeva Hulangamuwa Ganga Sirimanna Nandimithra Opathella Rhaiza DC Maingon Vishvanath Chandrasekharan 《Memórias do Instituto Oswaldo Cruz》2015,110(8):1017-1023
Leishmania donovani is the known causative agent of both cutaneous
(CL) and visceral leishmaniasis in Sri Lanka. CL is considered to be under-reported
partly due to relatively poor sensitivity and specificity of microscopic diagnosis.
We compared robustness of three previously described polymerase chain reaction (PCR)
based methods to detectLeishmania DNA in 38 punch biopsy samples
from patients presented with suspected lesions in 2010. Both,
Leishmaniagenus-specific JW11/JW12 KDNA and LITSR/L5.8S internal
transcribed spacer (ITS)1 PCR assays detected 92% (35/38) of the samples whereas a
KDNA assay specific forL. donovani (LdF/LdR) detected only 71%
(27/38) of samples. All positive samples showed a L. donovani
banding pattern upon HaeIII ITS1 PCR-restriction fragment length polymorphism
analysis. PCR assay specificity was evaluated in samples containing
Mycobacterium tuberculosis, Mycobacterium
leprae, and human DNA, and there was no cross-amplification in JW11/JW12
and LITSR/L5.8S PCR assays. The LdF/LdR PCR assay did not amplify M.
leprae or human DNA although 500 bp and 700 bp bands were observed in
M. tuberculosis samples. In conclusion, it was successfully shown
in this study that it is possible to diagnose Sri Lankan CL with high accuracy, to
genus and species identification, using Leishmania DNA PCR
assays. 相似文献