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1.
A historical mortality study of a cohort of employees of a gold mining and refining company was carried out in Salsigne, France. A major goal of the study was to investigate the relationship between lung cancer mortality and exposure to arsenic, radon, silica, and other contaminants of the working environment. A twofold excess of lung cancer was found both among miners and smelters, mainly concentrated among workers who had experienced exposure to past levels of arsenic, radon, and silica. The consistency of the results in the mine and the refinery are suggestive of a carcinogenic risk from both soluble and insoluble arsenic, although the potential role of other factors cannot be dismissed. © 1994 Wiley-Liss, Inc.  相似文献   
2.
The burden of injuries is underestimated to an even greater extent in developing countries than in industrialized countries. The objective of this paper is to analyze injuries and diseases in the monitored work place of the world's largest tin mining operation in Yunnan, South China.  相似文献   
3.
有色金属矿山的井下氡积累与矿工肺癌   总被引:1,自引:0,他引:1       下载免费PDF全文
作者调查了湖南省4个有色金属矿,在1976-1981年间测定的井下平均氡子体浓度为现行限值的2-13倍,最高424倍;进行回顾性流行病学调查,其观察48125人年,肺癌PMR1.43-3.33,SMR3.46-11.50,氡致肺癌的相对危险增加系数每WLM为).010-0.057。矿上同时暴露于含砷矿尘,部分3.46-11.50,氡致肺癌的相对危险增加系数每WLM为0.010-0.057。矿上同…  相似文献   
4.
目的了解室内空气中氡的本底水平,找出氡的不同来源对室内的相对贡献。方法 REM-2型氡析出率仪对地面和墙壁表面进行氡析出的测量,利用FD-125氡钍分析仪对室内用水和煤气中氡的含量作了分析,探讨了太原市居室内空气中氡本底水平。结果室内氡主要是由土壤、建材中析出的,其次才是室外空气中氡的渗入,室内用水和煤气中氡贡献很小。结论根据调查结果,进行室内空气中氡对人体健康危害分析和剂量评价,建立了室内氡本底水平的数据库,为以后研究室内氡的防护措施提供了依据。  相似文献   
5.
Estimating the effects of small doses of ionising radiation on DNA is one of the most important problems in modern biology. Different cytogenetic methods exist to analyse DNA damage; the cytokinesis-block micronucleus assay (CBMN) for human peripheral blood lymphocytes is a simple, cheap and informative cytogenetic method that can be used to detect genotoxic-related markers. With respect to previous studies on radiation-induced genotoxicity, children are a poorly studied group, as evidenced by the few publications in this area. In this study, we assessed radon genotoxic effects by counting micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in the lymphocytes of children who are long-term residents from areas with high radon concentrations. In the exposed group, radon was found to cause significant cytogenetic alterations. We propose that this method can be employed for biomonitoring to screen for a variety of measures.  相似文献   
6.
7.
Purpose: To study polymorphic variants of repair genes in people affected by long-term exposure to radon. The chromosome aberration frequency in peripheral blood lymphocytes was used as the biological marker of genotoxicity.

Materials and methods: Genotyping of 12 single nucleotide polymorphisms in DNA repair genes (APE, XRCC1, OGG1, ADPRT, XpC, XpD, XpG, Lig4 and NBS1) was performed in children with long-term resident exposure to radon. Quantification of the aberrations was performed using light microscopy.

Results: The total frequency of aberrations was increased in carriers of the G/G genotype for the XpD gene (rs13181) polymorphism in recessive model confirmed by the results of ROC-analysis (‘satisfactory predictor’, AUC?=?0.609). Single chromosome fragments frequency was increased in carriers of the G/G genotype in comparison with the T/T genotype. In respect to the total frequency of aberrations, the G/G genotype for the XpG gene (rs17655) polymorphism was also identified as a ‘satisfactory predictor’ (AUC?=?0.605). Carriers of the T/C genotype for the ADPRT gene (rs1136410) polymorphism were characterized by an increased level of single fragments relative to the T/T genotype.

Conclusion: The relationships with several types of cytogenetic damage suggest these three SNP (rs13181, rs17655 and rs1136410) may be considered radiosensitivity markers.  相似文献   
8.
Ovary detection is the first step in confirming ovarian lesions. The daughter cyst sign is widely used for this purpose; however, it is not always applicable. Recent improvements in image resolution allow Fallopian tube delineation, which can serve as a guide to identify the ovary. This anatomical approach (“follow the Fallopian tube” technique) comprises three steps: (1) confirm the uterus; (2) follow the Fallopian tube; and (3) find the ovary. Other applications of this approach include the differentiation between nonovarian and ovarian masses and ruling out ovarian torsion and an auto‐amputated ovary.  相似文献   
9.
Background Aspect ratio (AP), daughter artery ratio (DA), and lateral angle ratio (LA) have been reported in middle cerebral artery bifurcation aneurysms to correlate with rupture status.Objective To study the differences in AP, DA, LA, and aneurysm orientation between ruptured and unruptured basilar bifurcation aneurysms.Methods Three-dimensional (3D) angiograms of patients with basilar bifurcation aneurysms were analyzed for AP, DA, and LA. Aneurysm projection was classified as type A if the long axis of aneurysm was along basilar artery and type-B if otherwise.Results Thirty-one ruptured and 17 unruptured aneurysms were analyzed. The APs were significantly different (p = 0.008), 2.63 ± 1.1 for ruptured aneurysms and 1.7 ± 0.55 for unruptured aneurysms. AP ≥ 1.9 correlated with rupture status with 68% sensitivity and 70% specificity. Type-A configuration was significantly associated with ruptured aneurysms with an odds ratio (OR) of 5.9. LAs were 0.9 ± 0.4 and 1.4 ± 0.8 for ruptured and unruptured aneurysms, respectively, and the difference tended to be significant (p = 0.56). DAs were 1.25 ± 0.22 and 1.21 ± 0.19 for ruptured and unruptured aneurysms without any statistical difference.Conclusion AP > 1.9, type-A configuration, and lower LA is associated with ruptured basilar bifurcation aneurysms. DA did not differ between ruptured and unruptured aneurysms  相似文献   
10.
Abstract

Purpose: The aim of this study is to assess if there is a relationship between residential radon and lung cancer histological types and patients’ age at diagnosis.

Materials and methods: We conducted a multicenter hospital-based case-control study with eight participating hospitals. We included 216 never-smoking cases with primary lung cancer and 329 never-smoking controls. Controls were frequency matched with cases on age and sex distribution. Of them, 198 cases (91.7%) and 275 controls (83.5%) had residential radon measurements.

Results: Lung cancer risk reached statistical significance only for adenocarcinoma (Odds ratio [OR] 2.19; 95% Confidence interval [CI] 1.44–3.33), for other histologies the results were marginally significant. Residential radon level was higher for patients diagnosed before 50 and 60 years old than for older lung cancer cases.

Conclusions: Residential radon in never smokers seems to be a risk factor for all lung cancer histologies. Individuals diagnosed at a younger age have a higher residential radon concentration, suggesting an accumulative effect on lung cancer appearance.  相似文献   
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