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691.
Three cases of erosive pustular dermatosis of the scalp are reported. In all patients the dermatosis was characterized by pustular, erosive, and crusted lesions; in addition, two patients had areas of scarring alopecia. The results of laboratory tests, bacteriologic and mycologic investigations, and histopathologic examination were nondiagnostic. Although erosive pustular dermatosis of the scalp is characterized by a nonpathognomonic clinical and histopathologic picture, it probably represents a disease entity. 相似文献
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693.
The authors discuss the antenna test range at the US Naval Ocean Systems Center, which provides solutions to some formidable electromagnetics problems on ships. They describe the measurement approach; the pattern range, a 160 ft diameter ground plane constructed of prestressed concrete covered with a very thin coating of lead; the impedance range, which has a subterranean instrument room that houses the measurement equipment and personnel during the test; and the time-domain measurement range. The authors then examine computer modelling of antennas and analysis of the EMC (electromagnetic compatibility) problem. The modelling approach as presented is not limited to ships; it can work for power lines, buildings, and even mountains 相似文献
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696.
P Panayiotidis K Ganeshaguru C Rowntree SA Jabbar VA Hoffbrand L Foroni 《Canadian Metallurgical Quarterly》1997,97(4):844-847
Chromosome 13q deletion is among the most common cytogenetic abnormalities in chronic lymphocytic leukaemia (CLL). We investigated the 13q14.3 deletion in 44 CLL patients by Southern blotting following purification of clonal B CLL cells to >90%. Two sets of probes were used to investigate the site of clonal deletion, the D13S25 and D13S319 markers (at 13q14.3) and probes for exons 11 and 26-27 of the BRCA2 gene (at 13q12). Homozygous and heterozygous deletion at the 13q14.3 region was found in five and 17 patients, respectively. Despite the recent report of the BRCA2 gene involvement in >80% of CLL patients, we failed to detect a single case of homozygous or heterozygous deletion involving the 13q12 region. Our data support previous findings that the 13q14.3, and not the 13q12 region, is the major site of candidate tumour suppressor gene(s) in CLL. 相似文献
697.
The aim of the present study was to determine the association between the presence of Ureaplasma urealyticum in endotracheal aspirates and bronchopulmonary dysplasia (BPD). In addition, a review of similar studies from the English literature is presented. During the period February 1990 until March 1991, 108 mechanically-ventilated infants were included in a prospective study. Endotracheal aspirates were cultured for U. urealyticum. Birth weight, gestational age and development of BPD was recorded. Cultures were positive in 23 infants, resulting in a 21% colonization. The infants with positive cultures had a significantly lower gestational age (mean 28.9 vs 31.5 weeks; range 25-40 vs 25-42 weeks; p=0.0014). A positive U. urealyticum culture was not associated with a low birth weight (mean 1,390 vs 1,690 g; range 675-4,090 vs 700-3,600 g; p=0.0712). A positive U. urealyticum culture was significantly associated with BPD (p=0.0373). However, after correction for gestational age by logistic regression analysis, BPD failed to correlate with the presence of positive U. urealyticum cultures. A MEDLINE search of the English language literature was performed to identify all studies having the association of U. urealyticum colonization and BPD. Fourteen controlled studies were found. Five studies found no significant association between U. urealyticum colonization and BPD. In two studies, after correction for gestational age, the association between U. urealyticum colonization and BPD did not remain significant. In five studies with a significant association between U. urealyticum colonization and BPD, no correction for gestational age had taken place. In conclusion, U. urealyticum colonization is not associated with the development of bronchopulmonary dysplasia. U. urealyticum is often associated with gestational age and/or low birth weight; to investigate the association between U. urealyticum and bronchopulmonary dysplasia correction for both parameters should be made. 相似文献
698.
Alterations in the metabolism of arachidonic (20:4n-6), docosapentaenoic (22:5n-6), and docosahexaenoic (22:6n-3) acids and other polyunsaturated fatty acids in Zellweger syndrome and other peroxisomal disorders are reviewed. Previous proposals that peroxisomes are necessary for the synthesis of 22:6n-3 and 22:5n-6 are critically examined. The data suggest that 22:6n-3 is biosynthesized in mitochondria via a channelled carnitine-dependent pathway involving an n-3-specific delta-4 desaturase, while 20:4n-6, 20:5n-3 and 22:5n-6 are synthesized by both mitochondrial and microsomal systems; these pathways are postulated to be interregulated as compensatory-redundant systems. Present evidence suggests that 22:6n-3-containing phospholipids may be required for the biochemical events involved in successful neuronal migration and developmental morphogenesis, and as structural cofactors for the functional assembly and integration of a variety of membrane enzymes, receptors, and other proteins in peroxisomes and other subcellular organelles. A defect in the mitochondrial desaturation pathway is proposed to be a primary etiologic factor in the clinicopathology of Zellweger syndrome and other related disorders. Several implications of this proposal are examined relating to effects of pharmacological agents which appear to inhibit steps in this pathway, such as some hypolipidemics (fibrates), neuroleptics (phenothiazines and phenytoin) and prenatal alcohol exposure. 相似文献
699.
Inhalant use and use patterns, decision-making pertaining to inhalant use, cognitive capacity, cognitive egocentrism, and adherence to traditional ways were studied in a sample of male and female American Indian adolescents residing in a boarding home. Significant differences were not found for gender. Inhalant use group differences were found for only one variable, participation in tribal activities. For males, cognitive ability, cognitive egocentrism and participation in tribal activities were significant predictors of inhalant use/non-use. For females, tribal activities was the only significant predictor. 相似文献
700.
VA Kharchenko GM Dvojnos RC Krecek JR Lichtenfels 《Canadian Metallurgical Quarterly》1997,83(5):922-926
Cylicocyclus triramosus, a rare species of Cyathostominae from the southern African Burchell's zebra (Equus burchelli antiquorum) is redescribed, and a neotype is proposed. The external leaf-crown of the species consists of 30 elements and the internal leaf-crown numerous small and clear elements. The buccal capsule is cylindrical, oval in cross section, and approximately 3 times as wide as deep. The thin walls of the buccal capsule taper anteriorly from a large ringlike, hoop-shaped thickening around the posterior margin. The dorsal gutter is nipple-shaped. The mouth collar is notched dorsally and ventrally. The dorsal ray of the copulatory bursa is slightly elongate and distinctly set off from the lateral lobes. The branches of the dorsal ray have auxiliary branches. Appendages of the genital cone consist of 2 separated, large, semilunar plates with finger-shaped processes on the margins. The vulva-to-anus distance is greater than the tail length. The species is most similar to Cylicocyclus radiatus. Cylicocyclus triramosus differs from all similar species in the presence of dorsal and ventral notches in its mouth collar. In addition, C. triramosus also has a distinctive form of male genital cone appendage. Cylicocyclus radiatus differs further from C. triramosus in lacking a dorsal gutter and having a more elongate dorsal ray and a female tail nearly equal in length to the vulva-to-anus distance. 相似文献