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GL Clayman MG Stewart RS Weber AK el-Naggar EA Grimm 《Canadian Metallurgical Quarterly》1994,120(7):743-748
OBJECTIVE: To determine the relationship between human papillomavirus (HPV) DNA detection in upper aerodigestive tract malignancies and patient outcome. DESIGN: Archival paraffin-embedded specimens from 78 previously untreated patients with squamous carcinomas of the larynx and hypopharynx were pathologically verified and analyzed by polymerase chain reaction for detection of HPV DNA. Charts were independently reviewed and coded until final analysis. SETTING: The University of Texas M. D. Anderson Cancer Center, Houston, a tertiary cancer referral center. RESULTS: DNA was successfully extracted from 65 archival patient samples (83%). The mean (+/- SEM) duration of follow-up for these patients was 42 +/- 21 months. Thirty specimens (46%) exhibited detectable HPV DNA. Detection of HPV was significantly related to decreased survival, independent of disease stage. Log rank testing revealed that HPV detection, pathologic vascular invasion, and nodal status were the most significant predictors of death of disease. CONCLUSIONS: Laryngeal and hypopharyngeal carcinomas with detectable HPV may represent a biologically distinct subset of tumors that carry a poorer prognosis than do cancers with no detectable HPV. 相似文献
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Ade L Souza Júnior RS Poggetti B Fontes CO Bernini AM Figueiredo PD Branco D Birolini 《Canadian Metallurgical Quarterly》1996,51(6):247-249
Duodenal diverticulum is a common anatomic abnormality. Its inflammatory perforation is a rare complication, with less than 100 cases reported in the available literature. Traumatic perforation is exceedingly rare (only 3 cases reported). In this report one more case of traumatic perforation is presented, and the literature is reviewed focusing on the pathogenic, diagnostic and therapeutic aspects of this severe disease. 相似文献
134.
FJ Rocha LA Wickham JD Pena J Gao M Ono RW Lambert RS Kelleher DA Sullivan 《Canadian Metallurgical Quarterly》1993,46(6):737-749
Androgens are known to regulate both the structure and function of lacrimal tissue in a variety of species. To explore the endocrine basis for this hormone action, the following study was designed to: (1) determine the cellular distribution of androgen receptors in the lacrimal gland; and (2) examine the influence of gender and the endocrine environment on the glandular content of these binding sites. Lacrimal glands were obtained from intact, castrated, hypophysectomized, diabetic or sham-operated male or female adult rats, mice or hamsters, as well as from orchiectomized rats exposed to placebo compounds or physiological levels of testosterone. The cellular location of androgen receptors was evaluated by utilizing an immunoperoxidase protocol, in which a purified rabbit polyclonal antibody to the rat androgen receptor was used as the first antibody. Our findings with lacrimal glands showed that: (1) androgen receptors are located almost exclusively in nuclei of epithelial cells; (2) the cellular distribution or intranuclear density of these binding sites is far more extensive in glands of males, as compared to females; (3) orchiectomy or hypophysectomy, but not sham-surgery or diabetes, lead to a dramatic reduction in the immunocytochemical expression of androgen receptors; and (4) testosterone administration to orchiectomized rats induces a marked increase in androgen receptor content, relative to that in placebo-exposed glands. Our results also reveal that a 10 kb androgen receptor mRNA exists in the rat lacrimal gland. Overall, these findings demonstrate that gender and the endocrine system may significantly influence the distribution of androgen binding sites in rat lacrimal tissue. Moreover, our results show that androgens up-regulate their own lacrimal gland receptors. 相似文献
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RS Strobel AK Nagy AF Knowles J Buegel MD Rosenberg 《Canadian Metallurgical Quarterly》1996,271(27):16323-16331
An ecto-ATP diphosphohydrolase (ATPDase) was purified to homogeneity from vesiculosomes shed from chicken oviduct. First, the ecto-ATPDase-enriched vesiculosomes were concentrated by filtration, differential centrifugation, and exclusion chromatography. Next, the nonionic detergent, Nonidet P-40, was used to extract the ecto-ATPDase from vesiculosomal membranes, and the solubilized enzyme was further purified by ion exchange (DEAE-Bio-Gel) and lentil-lectin-Sepharose 4B chromatography. In the final stage, immunoaffinity chromatography was utilized to obtain purified ecto-ATPDase. More than 25,000-fold purification was achieved. Specific activity of the purified enzyme was greater than 800 micronol/min/mg of protein with MgATP as the substrate, the highest ever reported for an ATPDase. The enzyme also hydrolyzed other nucleoside triphosphates in the presence of magnesium at similar rates and CaATP and MgADP at lower rates. The molecular mass of the purified glycoprotein was 80 kDa as determined by SDS-polyacrylamide gel electrophoresis and Western blot analysis. Based on its enzymatic properties, the relationship of the chicken oviduct ecto-ATPDase with other reported ATPDases and ecto-ATPases is discussed. 相似文献
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