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751.
Professor Dr. med. Uwe Claussen Renate Ulmer Ernst Beinder Hans-Joachim Voigt 《黑龙江环境通报》1994,14(2):113-121
From September 1985 to March 1992, 804 amniotic fluid samples from 64 different diagnostic centres of the Federal Republic of Germany were sent to our laboratory exclusively for rapid karyotyping. The average time needed for notification of the analysed karyotype was 4·65 days when the ‘pipette method’ was used for chromosome harvesting and 5·97 days when the ‘in situ’ technique was used. The overall incidence of chromosome aberrations was 15·3 per cent. Data are presented about the likelihood of abnormal ultrasound findings being caused by chromosome aberrations. These findings include polyhydramnios, oligohydramnios, growth retardation, fetal effusions, neural tube defects, craniofacial defects, heart defects, gastroschisis and omphalocele, gastrointestinal tract defects, urinogenital defects, and limb defects. In future, such data need to contain larger numbers of cases for each week of gestation. This will improve the risk evaluation for each case with abnormal ultrasound findings, which should lead to better management during pregnancy, delivery, and postnatal care for those who require rapid karyotyping. 相似文献
752.
Dr W. J. Kleijer G. C. Geilen O. P. Van Diggelen R. A. Wevers F. J. Los 《黑龙江环境通报》1992,12(10):841-843
Prenatal analyses were performed in the pregnancy of the mother of a patient with β-mannosidase deficiency. Partial deficiency of β-mannosidase activity in the chorionic villi indicated a heterozygous fetus and this first-trimester diagnosis was subsequently confirmed by amniocentesis. 相似文献
753.
Juliette G. C. Omtzigt Frans J. Los Adriana M. Hagenaars Patricia A. Stewart Eva S. Sachs Professor Dr Dick Lindhout 《黑龙江环境通报》1992,12(11):893-897
In the context of a prospective study on the adverse effects of anti-epileptic drugs on fetal outcome, we evaluated our experience with prenatal diagnosis by ultrasonography and α- fetoprotein (AFP) determination in amniotic fluid. We compared these results with AFP values in maternal serum obtained prior to amniocentesis. From November 1985 to July 1990, amniocentesis at 16–18 weeks of gestation was performed in 267 pregnancies of 237 different women using anti-epileptic drugs. Among 92 pregnancies with maternal valproic acid use, five (including one concordantly affected monozygotic twin-pair) were terminated because of a spina bifida aperta, all prenatally diagnosed by AFP determination and acetylcholinesterase electrophoresis in amniotic fluid. The maternal serum AFP level was raised (⩾ 2.5 multiples of the median (MOM) for singleton pregnancies and ⩾ 4.5 MOM for twin pregnancies) in only two of these five affected pregnancies. We emphasize that maternal serum AFP levels may be unreliable for prenatal screening for fetal neural tube defects in women taking valproate and recommend that amniocentesis and fetal ultrasound examination should be offered directly. 相似文献
754.
F. Di Trapani M. Marino E. D'Alcamo I. Abate S. D'Agostino S. Lauricella M. Musicò F. Orlandi P. Sammarco Dr. A. Maggio B. Modell 《黑龙江环境通报》1991,11(12):899-904
Prenatal diagnosis of haemoglobin disorders is accepted to be a useful procedure to avoid births of infants with homozygous diseases. Advances in sampling and molecular techniques, such as polymerase chain reaction (PCR) and chorionic villus sampling (CVS), have made earlier and safer first-trimester prenatal diagnosis possible. However, these procedures need previous studies of at-risk couples, which can be very time-consuming when a number of different β-thalassaemia mutations occur in the region. We describe the possibility of making a first-trimester prenatal diagnosis by cordocentesis and fetal blood analysis at the 12th week of gestation. We found no statistically significant difference (p>0.05) between β/γ values in fetuses at the 12th and 18th weeks of gestation. In seven affected fetuses aborted at the 12th week of gestation, the diagnosis was confirmed in all cases by PCR analysis. These findings suggest that early cordocentesis could be an alternative procedure to CVS and PCR analysis. 相似文献
755.
Prenatal cytogenetic study of chorionic villi showed a discrepancy between a normal female karyotype 46,XX in the direct preparation after short-term incubation, and a 45,X karyotype in the long-term culture. The subsequent amniocentesis revealed a normal karyotype in three cultures and a 45,X/46,XX mosaicism in one culture. Cytogenetic analysis of chorionic villi after termination of the pregnancy showed a normal karyotype in the direct preparation and a 45,X/46,XX mosaicism in the long-term culture. Fetal lymphocytes showed normal karyotypes, whereas fibroblast cultures revealed a 45,X/46,XX mosaicism. 相似文献
756.
A rare chromosomal aberration consisting of a chromosomal shift was found in a woman who had prenatal diagnosis because she had previously had a malformed girl with phenotypic features compatible with the diagnosis of Patau syndrome. Chromosome analysis using G, C, and NOR banding showed a direct intrachromosomal insertion of bands 13q12 to 13q14 onto the short arm of chromosome 13 at band 13p13. We discuss this observation and compare it with other published reports of chromosomal shifts. 相似文献
757.
Dr G. Colucci E. Pesenti E. Molteni A. Lobbiani C. De Andreis S. Pariani F. Rossella A. E. Semprini G. Simoni 《黑龙江环境通报》1993,13(5):335-340
Maternal contamination of fetal DNA represents a major problem when highly sensitive molecular techniques are used in the prenatal diagnosis of genetic diseases. For this reason, we have studied the possibility of using DNA isolated from syncytiotrophoblast vesicles as a target of gene amplification (PCR). Three PCR systems were selected which included a repetitive 149 bp fragment of the Y chromosome, the VNTR locus D1S80, and a portion of the β-globin gene. The results of these experiments indicate that DNA isolated from syncytiotrophoblast vesicles is free of maternal contamination and is suitable for gene amplification and DNA analysis. 相似文献
758.
759.
Dr William Cusick Michael Bork Betsy Fabri Peter Benn John F. Rodis Louis Buttino JR 《黑龙江环境通报》1995,15(11):1078-1081
A 27-year-old gravida 4, para 3 was found to have anhydramnios at 14 weeks' gestation following a size/date discrepancy noted at her routine prenatal visit. A detailed ultrasound revealed multiple fetal anomalies including congenital heart defect, chest hypoplasia, and bilateral dysplastic kidneys. Karyotype revealed trisomy 16 in 15/15 cells from a tissue specimen obtained from the fetal cord insertion site following elective pregnancy termination. 相似文献
760.
Dr. S. Artan N. Başaran H. Hassa S. Özalp T. Şener B. S. Şayli C. Cengiz M. Özdemi̊ T. Durak I. Dölen T. Özgünen M. Tuna 《黑龙江环境通报》1995,15(12):1135-1142
In order to determine the incidence of confined placental mosaicism (CPM) in term placentae and to show the presence of specific sites and the effect on fetal development, 125 placentae from uneventful pregnancies were analysed by cytogenetic methods. The incidence was at least 4.8 per cent and there were no specific sites on the placenta. Although the number of cases is still too small, we found CPM to be associated with intrauterine growth retardation in six cases. 相似文献