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991.
GE Tiller ML Warman Y Gong JH Knoll R Mayne RG Brewton 《Canadian Metallurgical Quarterly》1998,81(3-4):205-207
Type IX collagen is a minor cartilage component which associates with mixed fibrils of types II/XI collagen. We have determined the precise physical and genetic locations for the gene encoding the alpha3 chain of type IX collagen, COL9A3. Utilizing fluorescence in situ hybridization, radiation hybrid mapping, and multipoint linkage analysis, we have mapped COL9A3 to human chromosome 20q13.3, 13 cM telomeric to D20S173. 相似文献
992.
Phytoestrogens: potential endocrine disruptors in males 总被引:1,自引:0,他引:1
R Santti S M?kel? L Strauss J Korkman ML Kostian 《Canadian Metallurgical Quarterly》1998,14(1-2):223-237
Exposure to diethylstilbestrol (DES) induces persistent structural and functional alterations in the developing reproductive tract of males. It is possible that xenoestrogens other than DES alter sexual differentiation in males and account for the increasing incidence of developmental disorders of the reproductive tract in men and wild animals. Phytoestrogens (coumestans, isoflavonoids, flavonoids, and lignans) present in numerous edible plants are quantitatively the most important environmental estrogens when their hormonal potency is assessed in vitro. They exert their estrogenic activity by interacting with estrogen receptors (ERs) in vitro. They may also act as antiestrogens by competing for the binding sites of estrogen receptors or the active site of the estrogen biosynthesizing and metabolizing enzymes, such as aromatase and estrogen-specific 17 beta-hydroxysteroid oxidoreductase (type 1). In theory, phytoestrogens and structurally related compounds could harm the reproductive health of males also by acting as antiestrogens. There are very little data on effects of phytoestrogens in males. Estrogenic effects in wildlife have been described but the evidence for the role of phytoestrogens is indirect and seen under conditions of excessive exposure. In doses comparable to the daily intake from soybased feed, isoflavonoids such as genistein were estrogen agonists in the prostate of adult laboratory rodents. When given neonatally, no persistent effects were observed. In contrast, the central nervous system (CNS)-gonadal axis and the male sexual behavior of the rat appear to be sensitive to phytoestrogens during development. The changes were similar but not identical to those seen after neonatal treatment with DES, but higher doses of phytoestrogens were needed. 相似文献
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994.
CP Porter NJ Pender LL Hayman ML Armstrong SK Riesch MA Lewis 《Canadian Metallurgical Quarterly》1997,45(6):252-257
As the scope of what constitutes health and the range of determinants of health-promoting and compromising behaviors among adolescents are expanded, APNs must be well prepared to be powerful influences in the lives of all adolescents. The guidelines offered by Bright Futures challenge nurse educators to prepare APNs who possess the core competencies to knowledgeably address the health issues and concerns of all adolescents in multiple settings. The American Academy of Nursing Expert Panel's recommendations contained herein, if implemented, will further enhance the capabilities of graduate programs to prepare APNs to provide developmentally and culturally relevant disease prevention and health promotion care to adolescents and their families. 相似文献
995.
A Bhatnagar R Shankar A Mondal MK Chopra ML Satija RV Narayanan 《Canadian Metallurgical Quarterly》1995,20(11):1003-1007
A pelvic hypervascular blush often creates a diagnostic dilemma during radionuclide abdominal imaging studies in females. This blush is shown to be due to uterine vascularity that is more prominent in the secretory and menstrual phases of the menstrual cycle. Significant uterine vascularity in the earlier phases is inappropriate and may be pathologic. Three such cases are presented in which increased uterine vascularity on radionuclide imaging during the proliferative phase either lead to a diagnosis or supported a clinical finding. 相似文献
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In 1851, Virchow introduced the term craniosynostosis to describe a variety of abnormalities in calvarial growth. These skull deformities are usually apparent in infancy. When an abnormal calvarial configuration is detected, a radiologic evaluation is necessary to characterize the deformity and to guide the corrective surgical procedure. Affected children are believed to have an improved outcome when diagnosis and surgical intervention occur at an early age. CT with three-dimensional reconstruction optimally evaluates the presence and degree of sutural involvement and assesses associated facial and intracranial abnormalities. This pictorial essay illustrates the imaging findings, nomenclature, and associated abnormalities of the various types of primary craniosynostosis. 相似文献
1000.