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排序方式: 共有1398条查询结果,搜索用时 140 毫秒
971.
Two male sibs with severe congenital megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) are presented. Both had enlarged bladder and hydronephrosis due to reduced bladder emptying, decreased bowel motility, and malrotation of the colon. Repeated careful ultrasound examination of the urinary tract in the second sib failed to show significant bladder enlargement prior to 25 weeks' gestation, which has been considered to be a reliable prenatal diagnostic sign for MMIHS. Slight bilateral enlargement of the renal pelves was noted at 21 weeks' gestation, and this may represent the earliest prenatally-detectable observation in this disease. Although more females than males with this condition have been reported, our cases provide support for an autosomal recessive mode of inheritance with a similar recurrence risk for both sexes. 相似文献
972.
In a case of fetal anaemia due to pure red cell anaemia (Blackfan-Diamond syndrome), two-dimensional fetal Doppler echocardiography revealed an altered blood flow velocity pattern with entire incorporation of the atrial contraction component in the early passive filling phase of the right ventricle. Intracardiac blood velocities were increased, whereas cardiac output was only moderately increased. The fetal heart rate was normal. It is concluded that in fetal anaemia the compensatory mechanisms are limited and restricted to an increase in stroke volume. The hypothesis that chronic fetal anaemia is associated with ‘high output cardiac failure’ corresponds well with the present findings. The technique described may prove to be useful in the early diagnosis of fetal anaemia. 相似文献
973.
Moshe Bronshtein Nathan Lewit Polo O. Sujov Imad R. Makhoul Dr Shraga Blazer 《黑龙江环境通报》1995,15(8):695-698
Ultrasonographic prenatal diagnosis of congenital diaphragmatic hernia is well established, but the correlation of prenatal detection with clinical outcome remains unclear. We report our experience with 15 cases of prenatally diagnosed congenital diaphragmatic hernia. Seven fetuses were detected at 14–16 weeks' gestation; two with a normal sonographic study at 15 and 16 weeks' gestation showed visceral herniation at 21 and 23 weeks, respectively. In the remaining six cases, a diaphragmatic hernia was found at ultrasonography after 24 weeks' gestation, while previous sonographic studies had been normal. All seven fetuses in whom a diaphragmatic hernia was diagnosed before 16 weeks' gestation were aborted; four of them had severe malformations or karyotype abnormalities. The two neonates who were diagnosed at 21 and 23 weeks' gestation died after surgical repair. In contrast, all six infants whose visceral herniation was diagnosed after 24 weeks of gestation, and whose sonographic studies at 15–23 weeks had been normal, are alive and well after corrective surgery. The results of this series suggest that the timing of visceral herniation into the thoracic cavity is a major indicator of the prognosis of these fetuses and that herniation that occurs after 25 weeks of gestation carries a favourable clinical outcome. Normal sonographic studies during the first half of pregnancy do not exclude the subsequent development of congenital diaphragmatic hernia, raising questions about the advisability of repeat examinations at later stages of gestation. 相似文献
974.
975.
Dr. Frank A. Firgaira Richard G. H. Cotton David M. Danks Kerry Fowler Anthony Lipson John S. Yu 《黑龙江环境通报》1983,3(1):7-11
Assay of dihydropteridine reductase in amniotic cells from a fetus at risk for malignant hyperphenylalaninemia is described. A normal result was obtained, this was confirmed after delivery. On two-dimensional polyacrylamide gel electrophoresis the enzyme from amniotic cells showed the same mobility as the mature liver reductase. 相似文献
976.
Dr Simon E. Meagher Nicholas M. Fisk Jonathan G. Harvey Geoffrey F. Watson Antheunis Boogert 《黑龙江环境通报》1993,13(6):495-501
Congenital bronchopulmonary malformations detectable on prenatal ultrasound include cystic adenomatoid malformation (CAM), lobar sequestration, and upper airway atresia. We describe three fetuses with prenatally detected intrathoracic lesions in which the associated pulmonary hyperechogenicity disappeared before delivery. In the first case of pulmonary sequestration, the infant was asymptomatic after birth. However, in a case of CAM and another with laryngeal atresia, respiratory distress developed after delivery, despite recent scans showing apparently normal lung fields. This experience suggests that ultrasonic resolution of hyperechogenic lung lesions in utero does not necessarily indicate resolution of the underlying pathology. 相似文献
977.
Initial screening for the common β-thalassaemia mutations with allele-specific oligonucleo-tide probes in an at-risk family suggested non-paternity. Subsequent DNA fingerprinting of the members proved otherwise. The mother had a codon 41/42 frameshift mutation and the father's defect, determined by direct sequencing of PCR-amplified β gene, was a codon 43 nonsense mutation. In the affected children, the close proximity of these two defects resulted in the absence of a hybridization signal to the normal probe in that region and a wrong assumption of homozygosity for the codon 41/42 mutation. The non-reactivity of the father's amplified DNA to the codon 41/42 thalassaemic probe accounted for the initial wrong conclusion of non-paternity. Since prior screening for β-thalassaemia mutations is done in all prenatal diagnosis programmes and concomitant inheritance of these two defects is relatively common in the Chinese, this ‘artefact’ of false non-paternity is worth noting. 相似文献
978.
Maternal serum human chorionic gonadotropin (hCG) and the free alpha-hCG subunit were evaluated in 249 women from 9 to 11 weeks gestation who subsequently underwent chorionic villus sampling for determination of fetal karyotype and in 20 women of 18 or more weeks gestation who were ascertained to have an aneuploid fetus by genetic amniocentesis. Seven of the first-trimester pregnancies were determined to be aneuploid and six had hCG levels in the normal range (one triploid pregnancy had elevated hCG levels) whereas 12 of the 20 secondtrimester cases had abnormal hCG levels and an additional three had elevated levels of alpha-hCG. This study confirms the previous report of abnormal maternal serum hCG levels in women with an aneuploid fetus at ≥ 18 weeks gestation and demonstrates that hCG evaluation is not useful at 9–11 weeks gestation for selecting pregnancies at risk for fetal aneuploidy. 相似文献
979.
Dr. Móshe Zeitune Moshe D. Fejgin Jacques Abramowicz Noah Ben Aderet Richard M. Goodman 《黑龙江环境通报》1988,8(2):145-149
We report two second trimester pregnancy terminations in the same woman following intrauterine ultrasonic findings of hydrops fetalis, polyhydramnios, lack of fetal movements, and short, fixed malformed limbs. One fetus also showed a cystic mass at the back of the head. Radiographic and anatomic studies of the fetuses demonstrated multiple pterygia, flexion contracture of multiple joints, abnormal facial appearance, cleft palate, pulmonary hypoplasia, and gracile bones. The cystic mass of the back of the head was found to be a cystic hygroma. These findings are consistent with the lethal variant of multiple pterygium syndrome. Early prenatal diagnosis of this condition is possible using ultrasonography. 相似文献
980.
Dorothy I. Bulas MD Howard M. Saal Jill Fonda Allen Sudesh Kapur Barbara M. Nies Kurt Newman 《黑龙江环境通报》1992,12(11):867-875
We report a case of cystic hygroma and diffuse lymphangiectasia detected by sonogram at 12 weeks' gestation. Fetal karyotype was normal. At 20 weeks' gestation, herniation of the bowel into the chest was noted. At delivery, the infant was diagnosed as having Fryns' syndrome. This is the first reported case of Fryns' syndrome presenting with cystic hygroma. 相似文献