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101.
Iida M. Kuroda N. Otsuka H. Hirose M. Yamasaki Y. Ohta K. Shimakawa K. Nakabayashi T. Yamauchi H. Sano T. Gyohten T. Maruta M. Yamazaki A. Morishita F. Dosaka K. Takeuchi M. Arimoto K. 《Solid-State Circuits, IEEE Journal of》2005,40(11):2296-2304
A 16 Mb embedded DRAM macro in a fully CMOS logic compatible 90 nm process with a low noise core architecture and a high-accuracy post-fabrication tuning scheme has been developed. Based on the proposed techniques, 61% improvement of the sensing accuracy is realized. Even with the smallest 5 fF/cell capacitance, a 322 MHz random-cycle access while 32 ms data retention time which contributes to save the data retention power down to 60 /spl mu/W are achieved. 相似文献
102.
The relationships between 4-hydroxy-2-nonenal (HNE), 2-thiobarbituric acid reactive substances (TBARS) and n-6 polyunsaturated fatty acids (n-6 PUFAs) were investigated for pork stored at 0, -20 and -80 degrees C. A significant linear correlation was apparent between HNE and TBARS for the pork stored at each temperature. However, the n-6 PUFA content remained unchanged during storage. 相似文献
103.
S Moriguchi M Hamada K Yamauchi K Sakai S Yamamoto 《Canadian Metallurgical Quarterly》1998,45(1-4):1-8
Spontaneously hypertensive rats (SHR) as a model for aging were used in this experiment and fed a regular (50 IU/Kg diet) or high vitamin E (500 IU/Kg diet) diet for 6 weeks. At 12 weeks old, they were killed and assayed. Although proliferation of thymic lymphocytes was significantly decreased in SHR fed the regular diet compared to Wistar Kyoto rats (WKY) fed the same diet, high vitamin E diet enhanced proliferation of thymic lymphocytes in SHR to almost the levels in WKY fed the regular diet. In addition, the expressions of both CD4 and CD8 antigens on CD+CD8+ T cells, immature T cells existing in thymic cortex, were also decreased in SHR, and significantly improved by high vitamin E diet. These results suggest that high vitamin E diet enhances thymic lymphocyte proliferation through increased T-cell differentiation in thymus. Then, the effect of vitamin E on T-cell differentiation in thymus was investigated by using male Fisher rats. Rats were divided into three groups; vitamin E-free, regular and high vitamin E groups and fed a diet containing various levels of vitamin E (0, 50 and 500 IU/Kg diet) for 7 weeks. Although the percentages of CD4+CD8- and CD4-CD8+ T cells in thymocytes were significantly greater in the high vitamin E group, the percentage of CD4+CD8- T cells inversely decreased in the vitamin E-free group compared to the regular group. We have tried to investigate the mechanism of the increased T-cell differentiation in thymus of rats fed the high vitamin E diet through cytokine production, and thymic epithelial cell (TEC) and macrophage functions. We have found that vitamin E enhances T-cell differentiation through the increase of not macrophage but TEC function in thymus, which is associated with the increased binding capacity of TEC to immature T cells via increased expression of adhesion molecule, ICAM-1. These results suggest that vitamin E is a potent nutrient for promoting health in the aged via the improvement of cellular immunity decreased with aging. 相似文献
104.
K Takeshita S Furui S Ban A Harasawa H Kohtake T Yamauchi Y Sasaki T Shirai Y Kikuchi 《Canadian Metallurgical Quarterly》1996,56(11):744-746
Helical computed tomography was performed with intravenous contrast material administration in ten patients with hepatic tumors (metastatic tumor, n = 6; hepatocellular carcinoma, n = 4). Maximum intensity projection (MIP) images of intrahepatic portal venous branches and hepatic veins, and shaded surface display (SSD) images of the hepatic tumors were reconstructed for each patient. The MIP image and SSD image were fitted to overlap on a single display to obtain three-dimensional (3-D) images showing both the hepatic vessels and hepatic tumors. Subsegmental localization of the tumors determined from the 3-D images proved to be correct in all of the six patients who received hepatic resection after examination. 3-D images seem to be useful for preoperative assessment of hepatic tumors. 相似文献
105.
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107.
The distribution of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) alpha and beta isoforms in the brainstem of adult rats was investigated using an immunohistochemical method with two monoclonal antibodies which specifically recognize the alpha and beta isoform, respectively. We found that these isoforms were differentially expressed by neurons in the substantia nigra, red nucleus, dorsal cochlear nucleus, pontine nuclei and inferior olivary nucleus. Neurons in the inferior olivary nucleus express the alpha isoform, but not the beta isoform. In contrast, neurons in the substantia nigra, red nucleus and pontine nuclei were immunostained with the beta antibody, but not with the alpha antibody. In the dorsal cochlear nucleus, neurons in layers I and II were alpha-immunopositive, whereas neurons in layers III and IV were beta-immunopositive. Therefore, the distribution of the CaM kinase II alpha-immunopositive neurons is completely different from that of CaM kinase II beta-immunopositive neurons. Next we examined the possible coexistence of CaM kinase II alpha isoform and glutamate or that of CaM kinase II beta isoform and glutamic acid decarboxylase (GAD) in the single neuron by double immunofluorescence labelling using a pair of anti-alpha and anti-glutamate antibodies, or a pair of anti-beta and anti-GAD antibodies. The results indicated that neurons expressing anti-alpha immunoreactivity were also immunopositive against anti-glutamate antibody, and neurons expressing beta isoform were also immunopositive against anti-GAD antibody, suggesting that alpha-immunopositive neurons are classified as excitatory-type neurons, and on the contrary, beta-immunopositive neurons are classified as inhibitory-type neurons. In conclusion, the present study confirmed that alpha- and beta-isoforms of CaM kinase II are differentially expressed in the nuclei of the brainstem and have different roles. 相似文献
108.
T Imai T Sugawara A Nishiyama R Shimada R Ohki N Seki M Sagara H Ito M Yamauchi T Hori 《Canadian Metallurgical Quarterly》1997,42(3):388-392
Ataxia telangiectasia (AT) is an autosomal recessive gene disorder, and ATM, a housekeeping gene, has been identified as the gene responsible for AT. Recently we found that another housekeeping gene, NPAT, is located upstream of ATM on human chromosome 11. The two housekeeping genes are transcribed in opposite directions and share a 0.5-kb 5' flanking sequence. The structure and organization of NPAT were determined by direct sequencing of cosmid clones carrying the gene and by application of the long and accurate (LA)-PCR method to amplify regions encompassing the exon/intron boundaries and all of the exons. The gene spans at least 44 kb and consists of 18 exons and 17 introns. It has been suggested that AT heterozygotes have an increased risk of developing cancer, especially breast cancer in women. Frequently, loss of heterozygosity at loci on 11q22-q24 has been observed in DNA isolated from tumors of the breast, uterine cervix, and colon, perhaps suggesting the location of a tumor suppressor gene in 11q22-q24. For investigation of the role of NPAT in AT and these tumors with allelic loss of 11q22-q24, appropriate primer sequences and PCR conditions for amplification of all the NPAT exons from genomic DNA were determined. We previously reported that no recombinations are found among Atm, Npat, and Acat1 (acetoacetyl-CoA thiolase) loci as determined by fine genetic linkage mapping of the mouse AT region. The results of the LA-PCR analysis using NPAT- and ACAT-specific primers and human genomic DNA allowed us to map ACAT 12 kb centromeric to NPAT. 相似文献
109.
D Kobayashi N Watanabe H Sasaki T Okamoto N Tsuji T Sato N Yamauchi Y Niitsu 《Canadian Metallurgical Quarterly》1998,76(4):552-555
The liver is an important target organ for gene therapy but its mitotic quiescence makes it resistant to integrative gene transfer. Retrovirus-based vectors integrate into liver cells in vivo but require the liver to be primed before transduction; experimentally a 70% hepatectomy is commonly used to stimulate regeneration, rendering the liver susceptible to transduction during the resulting wave of cell proliferation. Our aim was to develop a clinically acceptable method of inducing hepatocyte replication before in vivo retroviral gene transfer which is both simple and effective. We have used the physiological hormone tri-iodothyronine (T3) to stimulate hepatocyte replication. A single dose of T3 (400 micrograms/100 g bw) was given subcutaneously to euthyroid rats. This produced a labelling index of 31.7% in the hepatocyte population without histological or biochemical evidence of preceding liver damage. Following T3 administration the rat livers were transfected in vivo with an amphotropic retrovirus, TELCeB/AF-7 which encodes the beta-galactosidase reporter gene together with a nuclear localisation signal. Transgene expression was noted only within the liver where 1.3% of hepatocytes expressed the beta-galactosidase enzyme. This compared to 5.2% of hepatocytes transduced following a 70% hepatectomy, and 0.02% in animals receiving neither T3 nor partial hepatic resection before transduction. T3 administration is a simple way to prime the liver before in vivo retroviral vector-based gene transfer. 相似文献
110.
The purpose of this study was to determine whether the hypothesis on the levels of psychological processes (Hatta, 1977, 1978) accounts for lateral differences in arm positioning movement (a spatial localization task). Fifteen right-handed male subjects were asked to perform a constrained criterion movement, 12 cm in length, with the left or right arm. Then, after a 10-sec retention interval, they were asked to perform the movement with the same arm, estimating lengths of 6, 12 or 24 cm. Different levels of psychological processes were assumed to be involved in estimating these various movement lengths--half, the same, or double that of the original. All possible combinations of the arm (left/right) and three movement length were tested. The CE scores were lower (more accurate) for the left arm (half; 1.5 +/- 8.1 mm, same; 4.3 +/- 6.2mm, double; 5.9 +/- 20.3 mm) than those for the right arm (half; 5.9 +/- 7.6 mm, same; 10.6 +/- 10.6 mm, double; 11.8 +/- 23.6 mm) in all conditions, indicating a lateral difference (the right hemisphere dominance) in arm positioning tasks. This typical lateral difference, which displayed no significant difference among conditions, is supposed to be mediated by complex or high-level psychological processes. These psychological processes are required by the subjects in the estimation of the various movement lengths. This study suggests that the level of psychological processes is a crucial factor in the manifestation of lateral differences in the performance of arm positioning movements. 相似文献