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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
M Pan J Suárez de Lezo A Medina M Romero E Hernández J Segura F Melian F Wangüemert M Landin F Benítez M Amat F Velasco A Torres 《Canadian Metallurgical Quarterly》1997,80(10):1336-1338
Two hundred twenty-eight patients with successful coronary stent implantation were randomized either to protamine administration and femoral sheath removal (group I, n = 117) or no heparin neutralization and delayed sheath removal (group II, n = 111). The hospital stay after treatment was shorter in patients receiving protamine; therefore, protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation. 相似文献
992.
SW D'Souza E Rivlin J Cadman B Richards P Buck BA Lieberman 《Canadian Metallurgical Quarterly》1997,76(2):F70-F74
AIMS: To compare the outcome in in vitro fertilisation (IVF) children (after fresh embryo transfer) from multiple and singleton births with one another, and with normally conceived control children. METHODS: A cohort of 278 children (150 singletons, 100 twins, 24 triplets and four quadruplets), conceived by IVF after three fresh embryos had been transferred, born between October 1984 and December 1991, and 278 normally conceived control children (all singletons), were followed up for four years after birth. They were assessed for neonatal conditions, minor congenital anomalies, major congenital malformations, cerebral palsy and other disabilities. Control children, all born at term, were matched for age, sex and social class. RESULTS: The ratio of male:female births was 1.03. Forty six per cent of IVF children were from multiple births; 34.9% were from preterm deliveries; and 43.2% weighed less than 2500 g at birth. The IVF singletons were on average born one week earlier than the controls, weighed 400 g less, and had a threefold greater chance of being born by caesarean section. The higher percentage of preterm deliveries was largely due to multiple births and they contributed to neonatal conditions in 45.0% of all IVF children. The types of congenital abnormalities varied: 3.6% of IVF children and 2.5% of controls had minor congenital anomalies, and 2.5% of IVF children and none of the controls had major congenital malformations. The numbers of each specific type of congenital abnormality were small and were not significantly related to multiple births. IVF children (2.1%) and 0.4% of the controls had mild/moderate disabilities. They were all from multiple births, including two children with cerebral palsy who were triplets. CONCLUSIONS: The outcome of IVF treatment leading to multiple births is less satisfactory than that in singletons because of neonatal conditions associated with preterm delivery and disabilities in later childhood. A reduction of multiple pregnancies by limiting the transfer of embryos to two instead of three remains a high priority. 相似文献
993.
O Merimsky B Kaplan M Deutsch R Tirosh A Weinreb S Chaitchik 《Canadian Metallurgical Quarterly》1997,21(2):167-177
The effectiveness of detecting melanoma by measuring the intracellular fluorescein fluorescent polarization (IFFP) of patients' SCM (structuredness of the cytoplasmic matrix)-responding lymphocytes was examined. SCM-responding lymphocytes from 46 melanoma patients and 32 healthy volunteers were labeled with fluorescein diacetate and challenged with different stimuli, and the resulting polarization was determined. The polarizations (P) obtained upon stimulation with nothing (P-0), encephalitogenic factor (P-EF), phytohaemagglutinin (P-PHA), or melanoma antigen (P-MEL), and the ratios RR(ef) (P-EF/P-PHA) and RR(mel) (P-MEL/P-PHA) were lower for SCM-responding lymphocytes from the patients as a group than for those of the controls. The specificity and sensitivity of the IFFP tests (using cutoff values) to detect melanoma were 90.6 and 73.9%, respectively. The IFFP tests may facilitate the discrimination between melanoma patients and healthy subjects, and may be used in follow-up of patients with melanoma. 相似文献
994.
MyoD and Myf-5 differentially regulate the development of limb versus trunk skeletal muscle 总被引:1,自引:0,他引:1
B Kablar K Krastel C Ying A Asakura SJ Tapscott MA Rudnicki 《Canadian Metallurgical Quarterly》1997,124(23):4729-4738
The myogenic progenitors of epaxial (paraspinal and intercostal) and hypaxial (limb and abdominal wall) musculature are believed to originate in dorsal-medial and ventral-lateral domains, respectively, of the developing somite. To investigate the hypothesis that Myf-5 and MyoD have different roles in the development of epaxial and hypaxial musculature, we further characterized myogenesis in Myf-5- and MyoD-deficient embryos by several approaches. We examined expression of a MyoD-lacZ transgene in Myf-5 and MyoD mutant embryos to characterize the temporal-spatial patterns of myogenesis in mutant embryos. In addition, we performed immunohistochemistry on sectioned Myf-5 and MyoD mutant embryos with antibodies reactive with desmin, nestin, myosin heavy chain, sarcomeric actin, Myf-5, MyoD and myogenin. While MyoD(-/-) embryos displayed normal development of paraspinal and intercostal muscles in the body proper, muscle development in limb buds and brachial arches was delayed by about 2.5 days. By contrast, Myf-5(-/-) embryos displayed normal muscle development in limb buds and brachial arches, and markedly delayed development of paraspinal and intercostal muscles. Although MyoD mutant embryos exhibited delayed development of limb musculature, normal migration of Pax-3-expressing cells into the limb buds and normal subsequent induction of Myf-5 in myogenic precursors was observed. These results suggest that Myf-5 expression in the limb is insufficient for the normal progression of myogenic development. Taken together, these observations strongly support the hypothesis that Myf-5 and MyoD play unique roles in the development of epaxial and hypaxial muscle, respectively. 相似文献
995.
W. Fallmann P. Hudek I. Kostic A. Neubauer D. Pum I. Rangelow K. Riedling F. Rüdenauer U. B. Sleytr G. Stangl 《e & i Elektrotechnik und Informationstechnik》1998,115(7-8):349-353
This contribution describes the preparation, based upon a chemically amplified novolak resist (CAR), electron beam lithography, and ECR plasma etching, of structures with a high aspect ratio (10∶1) and lateral dimensions in the sub-micrometer range (150nm–300nm) which may serve as collector surfaces for sub-μm dust particles in a space experiment. 相似文献
996.
Bouferrache B. Krim G. Mejdoub N. Quanjer P.H. Freville M. Libert J.P. 《IEEE transactions on bio-medical engineering》1998,45(11):1305-1312
Dynamic modeling of lung C18O diffusion is used to measure the C18O transfer factor (TLco) of 14 newborns aged 1-4 mo. The model equation is based on the alveolar fractions of C18O and on changing alveolar ventilation induced by the rebreathing conditions. The model does not involve the volume of the rebreathing bag which is usually needed when applying rebreathing technique add which is a source of error. The equation is discretized and solved for recorded data obtained with equipment adapted to use in newborns. A least-square parameter calculation technique is applied to estimate TLco. Results show a strong relationship between this index and the biometrical ones and confirm those found in the literature featuring that the measurement duration can be considerably shortened 相似文献
997.
998.
The authors have exploited the ideas used in vector quantisation for error recovery of scalar quantised LSFs. The good performance of this method has provided high resistance of the LSFs to channel errors, outperforming other schemes by, possibly, a considerable margin. Better objective and subjective performances were obtained with this new method which obviates the need for more powerful FEC schemes for transmission over noisy channels.<> 相似文献
999.
Enzyme-linked immunosorbent assay and flow cytometric methods to screen hybridoma culture supernatants for antibodies to bovine neutrophils (surface antigen-specific) were optimized. Sensitivity of the 2 methods was compared. A panel of 14 murine monoclonal antibodies (MAB) to surface antigens of bovine polymorphonuclear neutrophilic leukocytes (neutrophils) was produced by hybridoma technology, and their isotypes were determined by whole-cell ELISA. Monoclonal antibody reactivity with neutrophils, eosinophils, and lymphocytes isolated on phosphate-buffered saline solution and on Ficoll-sodium diatrizoate were compared. Biochemical characterization of antigens recognized by MAB was performed by immunoblot analysis. Neutrophil plasma membranes were isolated on sucrose gradients (20, 32, and 50%) and purified for polypeptide characterization. Neutrophil surface proteins were characterized by external labeling with 125I. The flow cytometric method was proven to be more sensitive and rapid than ELISA to screen hybridoma supernatants. This method allowed light-scatter gating of live neutrophil populations for analysis, which eliminated nonspecific binding of antibodies to contaminating cells and dead neutrophils. The optimal conditions for flow cytometric analyses were 5 x 10(5) neutrophils and 1 micrograms of fluorescein-labeled F(ab')2/assay as the second antibody. The optimal conditions for hybridoma screening by ELISA were neutrophil concentration of 2.5 x 10(5)/well, using a 96-well polystyrene microtitration plate as solid support, and 2,2'-azino-di[3-ethyl-benzthiazoline sulfonate (6)] with H2O2 as the chromatogenic substrate. Tissue culture plates as solid support and 3,3', 5,5'-tetramethyl benzidine, with H2O2 as the chromogenic substrate, were equally as sensitive. Panel MAB reacted differently with neutrophils, eosinophils, and lymphocytes. Isolation of these cells from blood on Ficoll-sodium diatrizoate generally did not alter MAB reactivity. Coomassie blue-stained gels of neutrophil plasma membrane proteins contained about 25 polypeptide bands, 13 of which were major bands. Autoradiography revealed about 11 surface proteins, 5 of which were heavily labeled with 125I. Monoclonal antibody S7G8 identified a 65-kd protein and MAB S8G10 identified 65- and 70-kd proteins. On the basis of molecular weight, MAB S7G8 and S8G10 are comparable to human CD15, CD16, and CD64 molecules. The MAB generated in this study are potential candidates to discern bovine neutrophil function and heterogeneity. 相似文献
1000.
The urinary catheter is one of the most frequently used medical devices and has a long and intriguing history of development. This paper describes the catheter from its simple beginnings through the subtle but important changes it has undergone paralleling the advances in plastics technology witnessed this century. The changes have not been without controversy and the recent association of catheters with tissue toxicity, which has forced the implementation of strict guidelines for their manufacture and use, is described. 相似文献