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AIMS: To determine whether iron supplementation would enhance erythropoiesis in preterm infants treated with high doses of human recombinant erythropoietin (r-HuEPO). METHODS: Sixty three preterm infants were randomly allocated at birth to one of three groups to receive: r-HuEPO alone, 1200 IU/kg/week (EPO); or r-HuEPO and iron, 1200 IU/kg/week of r-HuEPO plus 20 mg/kg/week of intravenous iron (EPO + iron); or to serve as controls. All three groups received blood transfusions according to uniform guidelines. RESULTS: Infants in the EPO + iron group needed fewer transfusions than controls--mean (95% CI) 1.0 (0.28-1.18) vs 2.9 (1.84-3.88) and received lower volumes of blood--mean (95% CI) 16.7 (4.9-28.6) vs 44.4 (29.0-59.7) ml/kg. The EPO group also needed lower volumes of blood than the controls--mean (95% CI) 20.1 (6.2-34.2) vs 44.4 (29.0-59.7) ml/kg, but the same number of transfusions, 1.3 (0.54-2.06) vs 2.9 (1.84-3.88). Reticulocyte and haematocrit values from postnatal weeks 5 to 8 were higher in the EPO + iron than in the EPO group, and both groups had higher values than the controls. Mean (SEM) plasma ferritin was lower in the EPO group-65 (55) micrograms/l than in the EPO + iron group 780 (182) micrograms/l, and 561 (228) micrograms/l in the control infants. CONCLUSIONS: Early administration of high doses of r-HuEPO with iron supplements significantly reduced the need for blood transfusion. Intravenous iron (20 mg/kg/week in conjunction with r-HuEPO yielded a higher reticulocyte count and haematocrit concentration after the forth week of life than r-HuEPO alone. Infants treated with r-HuEPO alone showed signs of reduced iron stores. 相似文献
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VP Strekalovski? 《Canadian Metallurgical Quarterly》1983,29(1):27-29
The rates of colonic tumor growth were studied on the basis of evaluation of the case histories of 19 cancer patients in whom dynamic endocolonoscopy had been carried out. In some cases, malignant tumors appeared in the colon within 12 months after previous colonoscopy. Tumors were under 2.0 cm in size and were not accompanied by any clinical symptoms. Repeated endoscopic examinations performed within a period of 1-3 years detected large tumors which caused the constriction of colonic lumen. Clinical symptoms developed in such patients approximately 1-4 months prior to tumor detection. It is concluded that although the rates of growth of colonic malignancies are rather high, tumorigenesis is preceded by a long-term stage of preclinical disease. 相似文献
25.
The effects of anemia during lead exposures were studied using an infant baboon animal model. When the hemoglobin concentration was reduced to less than 70% of normal, a marked blood lead increase was observed and the free erythrocyte porphyrin value, aminolevulinic acid dehydratase activity and reticulocyte counts increased. Special emphasis should be placed on nutritional effects in lead exposures. 相似文献
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II Gitel'zon VP Nefedov VV Mezhevikin VA Samo?lov IuV Kotlovski? 《Canadian Metallurgical Quarterly》1977,84(7):23-24
Hypoxemia (45-minute) influence in vivo on erythropoietic activity of the kidney, liver, spleen, and sternum was studied by normoxemic perfusion of the isolated organs. The erythropoietic activity proved to increase after 6-hour perfusion of the liver; this confirmed the participation of this organ in the extrarenal secretion of the erythropoietic factor. 相似文献
28.
The present study employed intramuscular (i.m.) injections of the acetylcholine (ACh) receptor antagonist scopolamine hydrobromide (0.10 mg/kg) to investigate the possible involvement of ACh in naturally occurring spatial navigation in homing pigeons (Columba livia). Control pigeons receiving injections of saline or scopolamine methylbromide, an ACh antagonist that does not cross the blood-brain barrier, were oriented in a homeward direction when released from a location 8 km from home. In contrast, pigeons injected with scopolamine hydrobromide (0.10 mg/kg, i.m.) were less well oriented and took more time to return home from the same location. These results suggest that homing pigeon navigation is regulated, in part, by central cholinergic mechanisms. 相似文献
29.
131I dose-dependent thyroid autoimmune disorders in children living around Chernobyl 总被引:1,自引:0,他引:1
EV Vykhovanets VP Chernyshov II Slukvin YG Antipkin AN Vasyuk HF Klimenko KW Strauss 《Canadian Metallurgical Quarterly》1997,84(3):251-259
The nucleotide sequence of 35,400 bp at approximately 10 kb from the right telomere of chromosome VII was determined. The segment contains the MAL1 locus, one of the five unlinked loci sufficient for maltose utilization. Until now, each of these loci was considered to contain three genes (for regulator, permease and alpha-glucosidase), but a fourth gene, presumably an extra alpha-glucosidase gene, was found at MAL1 adjacent to the usual cluster of three genes. The two glucosidase genes are present in opposite orientation, forming an inverted repeat structure. In addition to the four genes at MAL1, there are 11 complete, non-overlapping open reading frames (ORFs) longer than 300 bp in the sequence presented here. A new ABC transporter gene (YGR281w), required for oligomycin resistance was found (YOR1; Katzman et al., 1995), and the previously sequenced BGL2 (YGR282c), ZUO1 (YGR285c) and BIO2 (YGR286c) genes were located. The sequence of BIO2, a biotin synthetase gene, required substantial correction and the size of Bio2p is 375, rather than 356, amino acids. Two ORFs show rather weak similarities to animal genes: YGR278w to an unknown ORF of Caenorhabditis elegans and YGR284c to the murine Surf-4, a member of a cluster of at least four housekeeping genes. The remaining five ORFs do not encode known functions, but three of these show weak to high similarities to other ORFs in the Saccharomyces cerevisiae genome and one (YGR280c) codes for a particularly lysine-rich protein. 相似文献
30.
M Bauchinger K Salassidis H Braselmann A Vozilova S Pressl G Stephan G Snigiryova VP Kozheurov A Akleyev 《Canadian Metallurgical Quarterly》1998,73(6):605-612
Bone morphogenetic proteins (BMPs) and their receptors (BMPRs) are thought to play an important role in bone morphogenesis. The purpose of this study was to determine the locations of BMP-2/-4, osteogenic protein-1 (OP-1, also termed BMP-7), and BMP type II receptor (BMPR-II) during rat fracture healing by immunostaining, and thereby elucidate the possible roles of the BMPs and BMPR-II in intramembranous ossification and endochondral ossification. In the early stage of fracture repair, the expression of BMP-2/-4 and OP-1 was strongly induced in the thickened periosteum near the fracture ends, and coincided with an enhanced expression of BMPR-II. On day 7 after fracture, staining for BMP-2/-4 and OP-1 immunostaining was increased in various types of chondrocytes, and was strong in fibroblast-like spindle cells and proliferating chondrocytes in endochondral bone. On day 14 after fracture, staining with OP-1 antibody disappeared in proliferating and mature chondrocytes, while BMP-2/-4 staining continued in various types of chondrocytes until the late stage. In the newly formed trabecular bone, BMP-2/-4 and OP-1 were present at various levels. BMPR-II was actively expressed in both intramembranous ossification and endochondral ossification. Additionally, immunostaining for BMP-2/-4 and OP-1 was observed in multinucleated osteoclast-like cells on the newly formed trabecular bone, along with BMPR-II. In reference to our previous study of BMP type I receptors (BMPR-IA and BMPR-IB), BMPR-II was found to be co-localized with BMPR-IA and BMPR-IB. BMP-2/-4 and OP-1 antibodies exhibited distinct and overlapping immunostaining patterns during fracture repair. OP-1 may act predominantly in the initial phase of endochondral ossification, while BMP-2/-4 acts throughout this process. Thus, these findings suggested that BMPs acting through their BMP receptors may play major roles in modulating the sequential events leading to bone formation. 相似文献