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991.
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993.
VV Frol'kis SM Novikova LN Bohats'ka RI Potapenko TH Mozzhukhina OK Kul'chyts'ky? MK Burchyns'ka HV Kopylova 《Canadian Metallurgical Quarterly》1997,43(3-4):3-10
Development and regression of experimental atherosclerosis in rabbits is an expressed age-related phenomenon, showing the increase in occurrence and pronouncement of atherosclerotic process with age. A new approach to the disease treatment by means of olivomycin is described. It has shown that while influencing considerably the protein biosynthesis of experimental animal, one can accelerate the regression of atherosclerosis by means of olivomycin and reduce protein and lipid metabolism indicators characterizing the disease development. 相似文献
994.
Whilst prostatic enlargement remains the commonest cause of bilateral hydronephrosis in males greater than 50 years of age, other rarer conditions such as retroperitoneal fibrosis should be borne in mind. We report a case of bilateral hydronephrosis which was eventually diagnosed as idiopathic retroperitoneal fibrosis and treated with open surgical ureterolysis with omental wrapping. 相似文献
995.
BACKGROUND: Adrenal cortical carcinoma is a rare and highly malignant neoplasm. Liver metastases from it may require special differential techniques in addition to cytologic findings. CASE: A 14-month-old child had adrenal cortical carcinoma and a liver metastasis confirmed by fine needle aspiration biopsy (FNAB). Histologic and clinical criteria of malignancy only partially applied to this tumor. Immunohistochemical analysis of both the primary tumor and metastasis supported an adrenal cortical origin. Other ancillary tests-DNA ploidy, proliferation index (proliferating cell nuclear antigen, Ki-67) and p53 protein immunolocalization-were utilized in a diagnostic sequence. Flow cytometric and image analysis of DNA ploidy of the primary tumor gave similar results. Assessment of DNA content of the adrenal cortical carcinoma and liver metastasis by image analysis showed identical patterns. CONCLUSION: The applicability of new diagnostic techniques to FNAB material may provide new objective measures of the biologic potential of adrenal cortical carcinoma. The validity of these tests is enhanced with the use of image-based quantitative approaches that provide greater reproducibility and objectivity of their results. 相似文献
996.
SL Ness W Edelmann TD Jenkins W Liedtke AK Rustgi R Kucherlapati 《Canadian Metallurgical Quarterly》1998,273(37):23904-23911
Keratins are intermediate filaments of epithelial cells. Mutations in keratin genes expressed in skin lead to human disorders, including epidermolysis bullosa simplex and epidermolytic hyperkeratosis. We examined the role of keratin 4 (K4) in maintaining the integrity of internal epithelial linings by using gene targeting to generate mice containing a null mutation in the epithelial K4 gene. Homozygous mice that do not express K4 develop a spectrum of phenotypes that affect several organs which express K4 including the esophagus, tongue, and cornea. The cellular phenotypes include basal hyperplasia, lack of maturation, hyperkeratosis, atypical nuclei, perinuclear clearing, and cell degeneration. These results are consistent with the notion that K4 is required for internal epithelial cell integrity. As mutations in K4 in humans lead to a disorder called white sponge nevus, the K4-deficient mice may serve as models for white sponge nevus and for understanding the role of K4 in cellular proliferation and differentiation. 相似文献
997.
W Dong MK Selgrade IM Gilmour RW Lange P Park MI Luster FW Kari 《Canadian Metallurgical Quarterly》1998,19(3):462-469
The capacity of four chicken lines (Y11, L2, B13, PA12) to control Salmonella enteritidis (SE) phage type 4 (PT4) systemic colonization was investigated. Thirteen-week-old chickens were intravenously inoculated with 10(6) SE colony-forming units, and the levels of SE colonization were determined at various time intervals after inoculation in liver, spleen, genital organs, and ceca. The course of SE infection showed a rapid contamination of liver, spleen, and genital organs, whereas the ceca were infected later. A significant (P < 0.001) effect of the chicken line on levels of SE was detected on day 3 postinoculation (PI) in liver and ceca, on day 10 PI in ceca, and on day 15 PI in spleen. Because an early control of systemic Salmonella infection by the Ity/Nramp1 gene has been demonstrated in mice, we aimed to study the early resistance of chickens to SE. As a consequence, we then focused our study on the between- and within-line variabilities of SE levels on day 3 PI. According to the SE levels in liver on day 3 PI, the chicken lines could be classified as susceptible (Y11 and L2) or resistant (PA12 and B13). This early variability was explored in resistant B13 and susceptible L2 lines. Differences between these two lines were confirmed in liver but not in ceca. A large within-line variability was observed in all organs of these two lines. The genetic origin of this variability will have to be determined as a prerequisite to an eventual selection. 相似文献
998.
JR Keltner LL Wald PJ Ledden YC Chen RT Matthews EH Küestermann JR Baker BR Rosen BG Jenkins 《Canadian Metallurgical Quarterly》1998,39(4):651-656
OBJECTIVES: Despite decreasing infant mortality in North Carolina, the gap between African Americans and Whites persists. This study examined how racial differences in infant mortality vary by maternal education. METHODS: Data came from Linked Birth and Infant Death files for 1988 through 1993. Multiple logistic regression models adjusted for confounders. RESULTS: Infant mortality risk ratios comparing African Americans and Whites increased with higher levels of maternal education. Education beyond high school reduced risk of infant mortality by 20% among Whites but had little effect among African Americans. CONCLUSIONS: Higher education magnifies racial differences in infant mortality on a multiplicative scale. Possible reasons include greater stress, fewer economic resources, and poorer quality of prenatal care among African Americans. 相似文献
999.
OBJECTIVE: Benign tumors account for less than 1% of testicular tumors and the incidence is even lower in children. A rare case of epidermoid cyst of the testis in a child is described. The differential diagnosis and treatment options are discussed. METHODS/RESULTS: A case of unilateral epidermoid cyst of the testis in an 11-year-old boy is presented. The clinical and diagnostic aspects are discussed. Definitive diagnosis could be made only after surgical excision. CONCLUSIONS: Pathological analysis of the entire testis is warranted to make the definitive diagnosis of epidermoid cyst. However, preservation of the testis can be considered, particularly in those cases with bilateral involvement, if supported by solid, consistent diagnostic evidence, including intraoperative biopsy. 相似文献
1000.
MK Mengel AE Stiefenhofer E Jyv?sj?rvi KD Kniffki 《Canadian Metallurgical Quarterly》1993,55(2):159-169
Cold stimuli of varying intensities were randomly applied to upper middle incisors of 12 healthy young subjects for a mean duration of 2 min by individually adapted thermodes the temperatures of which ranged from +30 degrees C to -30 degrees C. The subjects were asked to rate the magnitude of their pain sensations during application of the stimuli by means of a linear potentiometer according to a category scale. After each stimulus, they were asked to describe the quality of their pain sensations. Cold stimulation of the teeth evoked pain sensations were reproducible that in subsequent trials and could be graded according to stimulation intensity. Below certain individually different threshold thermode temperatures the onset of a stimulus was followed, after a short latency (1.6 +/- 1 sec), by a sharp and shooting pain sensation which immediately decreased after reaching its maximum value while the stimulus was still present. The mean maxima of the pain intensities were correlated to the thermode temperature. In general, this first pain component was followed by a second one (latency: 29.9 +/- 6.3 sec) with a lower threshold temperature, less of an increase in rate and lower magnitude. This was described as a dull, burning pain which was difficult to localize. The human pain ratings are compared to recordings of intradental nerve fibres in the cat and, under the assumption that the response behaviour of human pulpal nerve fibres is comparable to that of the cat, we hypothesize that the first pain component is evoked by intradental A delta fibres exhibiting their typical phasic response behaviour and firing during the initial steep temperature decrease. After some seconds, intradental temperature reached values sufficient to evoke C-fibre activity associated with the second pain component. 相似文献