全文获取类型
收费全文 | 380篇 |
免费 | 19篇 |
国内免费 | 46篇 |
专业分类
安全科学 | 38篇 |
环保管理 | 33篇 |
综合类 | 225篇 |
基础理论 | 101篇 |
环境理论 | 1篇 |
污染及防治 | 16篇 |
评价与监测 | 10篇 |
社会与环境 | 9篇 |
灾害及防治 | 12篇 |
出版年
2023年 | 4篇 |
2022年 | 6篇 |
2021年 | 13篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2017年 | 6篇 |
2016年 | 8篇 |
2015年 | 4篇 |
2014年 | 8篇 |
2013年 | 17篇 |
2012年 | 8篇 |
2011年 | 32篇 |
2010年 | 12篇 |
2009年 | 13篇 |
2008年 | 16篇 |
2007年 | 17篇 |
2006年 | 28篇 |
2005年 | 20篇 |
2004年 | 23篇 |
2003年 | 18篇 |
2002年 | 16篇 |
2001年 | 13篇 |
2000年 | 4篇 |
1999年 | 9篇 |
1998年 | 6篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 14篇 |
1994年 | 15篇 |
1993年 | 6篇 |
1992年 | 10篇 |
1991年 | 17篇 |
1990年 | 3篇 |
1989年 | 14篇 |
1988年 | 10篇 |
1987年 | 13篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 4篇 |
排序方式: 共有445条查询结果,搜索用时 31 毫秒
41.
42.
Truncus arteriosus (TA) is a rare cardiac anomaly constituting less than 1% of all congenital heart defects. Its association with complete atrioventricular septal defect (AVSD) is extremely unusual and only 12 cases diagnosed postnatally or postmortem have been reported so far. We describe the first case of truncus arteriosus with AVSD to be diagnosed prenatally by fetal echocardiography. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
43.
44.
Ken Kin Lam Yung Pengfei Fu Yufei Zhao Chuan Dong Zongwei Cai Ruijin Li 《环境科学学报(英文版)》2022,34(12):25-40
Fine particulatematter (PM2.5) is associated with increased risks of Alzheimer’s disease (AD),yet the toxicologicalmechanisms of PM2.5 promoting AD remain unclear. In this study,wildtype
and APP/PS1 transgenic mice (AD mice) were exposed to either filtered air (FA) or PM2.5 for eight weeks with a real-world exposure system in Taiyuan, China (mean PM2.5 concentration
in the cage was 61 μg/m3). We found that PM2.5 exposure could remarkably aggravate AD mice’s ethological and brain ultrastructural damage, along with the elevation of the pro-inflammatory cytokines (IL-6 and TNF-α), Aβ-42 and AChE levels and the decline of ChAT levels in the brains. Based on high-throughput sequencing results, some differentially expressed (DE) mRNAs and DE miRNAs in the brains of AD mice after PM2.5 exposure were screened.Using RT-qPCR, seven DEmiRNAs (mmu-miR-193b-5p, 122b-5p, 466h-3p, 10b-5p, 1895, 384–5p, and 6412) and six genes (Pcdhgb8, Unc13b, Robo3, Prph, Pter, and Tbata)
were evidenced the and verified. Two miRNA-target gene pairs (miR-125b-Pcdhgb8 pair and miR-466h-3p-IL-17Rα/TGF-βR2/Aβ-42/AChE pairs) were demonstrated that they were more
related to PM2.5-induced brain injury. Results of Gene Ontology (GO) pathways and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways predicted that synaptic and postsynaptic
regulation, axon guidance, Wnt, MAPK, and mTOR pathways might be the possible regulatory mechanisms associated with pathological response. These revealed that PM2.5-
elevated pro-inflammatory cytokine levels and PM2.5-altered neurotransmitter levels in AD mice could be the important causes of brain damage and proposed the promising miRNA
andmRNA biomarkers and potentialmiRNA-mRNA interaction networks of PM2.5-promoted AD. 相似文献
45.
46.
47.
Maria Okumura Vera Aparecida dos Santos Mário E. Camargo Regina Schultz Marcelo Zugaib 《黑龙江环境通报》2004,24(3):179-181
The prenatal diagnosis of congenital transmission of Chagas' disease in a pregnant woman with the indeterminate form of the disease is reported. Sonography revealed fetal hydrops at 31 weeks' gestation. Anti-Trypanosoma cruzi IgM and IgG antibodies were negative in the fetal blood sampled by cordocentesis, but T. cruzi trypomastigotes were found in its buffy coat. Owing to anemia, in utero exchange transfusion was undertaken, but fetal demise ensued. Labor was induced and a stillborn infant weighing 2030 g was delivered. The pathological examination revealed placentitis and meningoencephalitis, myocarditis and splenitis in the stillborn fetus. Amastigotes were found in the myocardium, brain and placenta. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
48.
49.
50.
为了研究人群在自然属性和社会属性分类下的效应修饰作用,利用2005~2011年北京市大气PM2.5日均浓度、气象要素及循环系统疾病每日死亡人数数据,根据不同年龄、性别及学历将人群分组,采用时间序列的半参数广义相加模型(GAM),定量评价大气PM2.5对居民循环系统疾病死亡人数的影响.单污染物模型和多污染物模型结果表明,PM2.5为影响循环系统疾病每日死亡人数的主要大气污染物.北京市空气中PM2.5的浓度每增加10μg/m3,循环系统疾病总死亡人数增加0.50%(95% CI:0.36,0.63).不同人群的易感程度不同,各人群死亡人数的增加范围为0.23~0.71%,女性、60~74岁人群、文盲人群的健康风险相对较高.在文盲人群中,老年(60+)女性占比为66.2%,为了分离社会属性人群分类中可能存在的自然属性因素干扰,本文去除其中老年、女性这两个混杂因素的影响,文盲人群健康风险仍然大于较高学历的人群.年龄和性别因素叠加在学历因素上,可能加大低学历人群的健康风险,对于这部分叠加了自然因素和社会因素双重敏感性的人群应给与重点关注. 相似文献