全文获取类型
收费全文 | 226篇 |
免费 | 2篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 1篇 |
环保管理 | 6篇 |
综合类 | 157篇 |
基础理论 | 9篇 |
污染及防治 | 8篇 |
评价与监测 | 24篇 |
社会与环境 | 1篇 |
灾害及防治 | 11篇 |
出版年
2022年 | 3篇 |
2021年 | 4篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 7篇 |
2014年 | 9篇 |
2013年 | 4篇 |
2012年 | 3篇 |
2011年 | 9篇 |
2010年 | 11篇 |
2009年 | 18篇 |
2008年 | 13篇 |
2007年 | 13篇 |
2006年 | 8篇 |
2005年 | 9篇 |
2004年 | 9篇 |
2003年 | 7篇 |
2002年 | 16篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1995年 | 9篇 |
1994年 | 13篇 |
1993年 | 7篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 6篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 2篇 |
排序方式: 共有231条查询结果,搜索用时 15 毫秒
101.
Jeanne M. Meck PhD. Chahira Kozma Jean-Gilles Tchabo Jeffrey C. King Shaun Lencki Thomas L. Pinckert 《黑龙江环境通报》1994,14(9):878-883
Follow-up evaluations were performed on a child at the ages of 2 years 8 months and also at 5 years who had been found on prenatal amniocentesis to be mosaic for trisomy 12. Eight of 36 colonies (22 per cent) were trisomy 12 at amniocentesis, with the remaining colonies showing a normal female karyotype. Cord blood, amnion, chorion, placental, and skin fibroblast chromosome studies failed to show any further evidence of a trisomy 12 cell line. At her evaluations, the child had normal physical and neurological findings. Psychomotor development was appropriate for age on screening. 相似文献
102.
R. Douglas Wilson 《黑龙江环境通报》1995,15(13):1259-1273
Early amniocentesis at less than 14 weeks gestation is becoming more common in prenatal diagnosis populations. Randomized studies are minimal and have not had the power to determine the accuracy and safety of the procedure compared to chorionic villus sampling or mid-trimester amniocentesis. Procedures at 11+0-12+6 weeks should be considered experimental. This clinical review considers the ethics, embryology, and clinical experience (cytogenetics, AFP, AChE, procedure and cytogenetic failures, spontaneous and therapeutic pregnancy losses, congenital anomalies) of early amniocentesis. 相似文献
103.
P. M. Grosheide H. W. P. Quartero Professor Dr S. W. Schalm R. A. Heijtink G. C. M. L. Christiaens 《黑龙江环境通报》1994,14(7):553-558
From 1982 to 1989, pregnant women in two large city hospitals in The Netherlands had serum samples screened for hepatitis B surface antigen (HBsAg). Infants of mothers found to be HBsAg-positive received hepatitis B immune globulin immediately after birth and hepatitis B vaccine in the first year of life. Blood samples of infants were regularly tested for HBsAg and antibodies directed against HBsAg. A retrospective analysis of the pregnancy outcome in HBsAg-positive women who had invasive tests for prenatal diagnosis was carried out to determine whether amniocentesis and chorionic villus sampling (CVS) are risk factors for the intrauterine transmission of the hepatitis B virus. Amniocentesis was carried out in 17 HBsAg-positive women and CVS in one case. Only two women were HBsAg- and HBeAg-positive. Prenatal diagnosis led to the termination of pregnancy for fetal chromosome abnormality in three cases. The remaining 15 pregnancies were uneventful; all infants were negative for HBsAg and developed an active immune response to the vaccine. These data suggest that amniocentesis in HBsAg-positive women constitutes a low risk for the intrauterine transmission of the hepatitis B virus, but definite conclusions in HBeAg-positive women cannot be drawn. 相似文献
104.
Beth A. Pletcher Maureen M. Sanz Jerrold S. Schlessel Suphat Kunaporn Carrie McKenna Martin G. Bialer M. Lita Alonso Ann-Leslie Zaslav W. Ted Brown James H. Ray 《黑龙江环境通报》1994,14(10):933-940
Two phenotypically abnormal liveborns in whom trisomy 16 mosaicism was diagnosed prenatally by amniocentesis are described. Analysis of a percutaneous umbilical blood sample in one case revealed a normal chromosomal complement. Ultrasound examinations performed at the time of amniocentesis were normal. Serial sonography during the late second and third trimesters demonstrated progressive intrauterine growth retardation (IUGR) in both fetuses and a cardiac defect in one. At birth, both infants had dysmorphic features and multiple congenital anomalies. Trisomy 16 mosaicism was confirmed postnatally in both infants in skin fibroblasts; however, peripheral blood samples contained only chromosomally normal cells. The two mosaic trisomy 16 cases described in this report, together with the five confirmed cases reported previously, demonstrate the need for caution in the counselling of patients when trisomy 16 mosaicism is diagnosed prenatally in amniotic fluid samples. Such cases potentially can result in the birth of dysmorphic infants with significant birth defects, growth retardation, and possible developmental disabilities. 相似文献
105.
Cacops, one of the most distinctive Paleozoic amphibians, is part of a clade of dissorophoid temnospondyls that diversified in the
equatorial region of Pangea during the Late Carboniferous and Early Permian, persisting into the Late Permian in Central Russia
and China. Dissorophids were a successful group of fully terrestrial, often spectacularly armoured predators, the only amphibians
apparently able to coexist with amniotes when the latter started to dominate terrestrial ecosystems. In this paper, we describe
excellent new skulls from the Early Permian of Oklahoma attributed to Cacops, Cacops morrisi sp. nov. and provide for the first time detailed information about this iconic dissorophid. These specimens show anatomical
and ontogenetic features that will impact on future studies on the evolution of terrestriality in tetrapods. For example,
the large, posteriorly closed tympanic embayment has fine striations on an otherwise smooth surface, documenting the oldest
known clear evidence for the presence of a tympanic membrane in the fossil record, a structure that is used for hearing airborne
sound in extant tetrapods. The skull of C. morrisi also has several features associated with predatory behaviour, indicating that this dissorophid may have been one of the
top terrestrial predators of its time. 相似文献
106.
107.
108.
对某铁路机务段420名一线职工进行心理健康状况的现况研究并探索其影响因素,初步建立心理健康风险评估模型。整群抽取420例样本,采用症状自评量表(SCL-90)进行心理健康水平测评,与全国常模比较,采用二分类Logistic心理健康风险预警模型进行回归分析。结果表明,铁路一线职工在躯体化、饮食睡眠情况、敌对、强迫症状方面的得分均高于全国常模。年龄、文化程度、现职工种、劳动班制、工龄等因素影响职工心理健康状况。进而提出应做好职工心理疏导工作,探索一线职工心理健康预警指标,实现风险识别关口前移,保障铁路运输安全。 相似文献
109.
110.