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Cloning and expression analysis of the chick DAN gene, an antagonist of the BMP family of growth factors. 总被引:3,自引:0,他引:3
Lisa M Gerlach-Bank Amanda D Ellis Bridgette Noonen Kate F Barald 《Developmental dynamics》2002,224(1):109-115
Differential screening-selected gene aberrative in neuroblastoma (DAN) is a member of a cystine knot protein family that includes Cerberus and Gremlin. First isolated in a screen to identify genes down-regulated in transformed rat fibroblasts, DAN has subsequently been cloned in Xenopus, mouse, and human. Overexpression of DAN suppresses the transformed phenotype and retards the cell's entry into S phase. Biochemical analyses have demonstrated DAN's ability to bind bone morphogenetic proteins and antagonize their signaling activity. In this study, chick DAN was cloned and sequenced, revealing a conserved cystine knot region as well as an N-glycosylation site. A riboprobe was designed from the 3' chick DAN coding sequence and used for analysis of DAN in the developing chick embryo by in situ hybridization. Chick DAN was expressed beginning at stage 10 in the developing somites and the medial otic epithelium. Expression in the neural layer of the eye became apparent at stage 14. By stage 17, expression had expanded to the base of the hindbrain. Limb bud labeling began at stage 20, whereas expression in the branchial arches appeared at stage 25. Chick DAN expression generally corresponded to that of mouse DAN expression as shown by comparative in situ hybridization. However, chick DAN was found in the otic epithelium and notochord, whereas mouse DAN was restricted to the overlying otic ectomesenchyme and was absent from the notochord. This observation suggests that DAN may play different roles in chick and mouse otic and notochord development. 相似文献
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Russell S. Kirby 《分娩》2004,31(2):148-151
Commentary on: Zhang J, Yancey MK, Henderson CE. U.S. national trends in labor induction, 1989–1998. J Reprod Med 2002;47:120–124. MacDorman MF, Mathews TJ, Martin JA, Malloy MH. Trends and characteristics of induced labour in the United States, 1989–98. Paediatr Perinat Epidemiol 2002;16:263–273. Kozak LJ, Weeks JD. U.S. trends in obstetric procedures, 1990–2000. Birth 2002;29:157–161. Abstract: Three recent studies examined the national trend in labor induction in the United States. All show a doubling in the rate of induction during the 1990s, although vital statistics data show a consistently higher trend than that obtained from national hospital discharge data. Neither data source adequately documents the full range of indications for induction, its timing, hospital staffing considerations, and other factors that may play a role. Although rates of induction of labor may be leveling off, despite a lack of scientific evidence for its widespread use, rates are likely to remain at current levels for the next few years. 相似文献
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Carol Sigelman Tamara Didjurgis Brenda Marshall Frank Vargas Amanda Stewart 《Child psychiatry and human development》1992,22(4):265-276
Native American, Hispanic, and Anglo sixth graders reacting to an example of teenage problem drinking expressed similar beliefs and attitudes in many respects. However, Native American children viewed the problem as less serious, subscribed more to a disease theory of alcoholism, attributed less causal responsibility to the individual, and adopted a less aggressive approach toward treatment than did Hispanic, and especially Anglo, children. Their less conventional value orientations accounted for all these differences except their stronger endorsement of a disease theory of problem drinking. 相似文献
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The University Hospital Nurse Extender Model using patient care technicians is a long-term strategy to maintain quality patient care. The authors present an overview and conceptual framework of the model. In future papers in this four-part series, the authors will discuss the implementation and evaluation of the model and describe six lessons learned during the implementation process. This information will be useful to any nursing administrator planning to implement a change in the way patient care is delivered. 相似文献
27.
Janine A Danks Patricia M W Ho Amanda J Notini Frosa Katsis Peter Hoffmann Bruce E Kemp T John Martin Jeffrey D Zajac 《Journal of bone and mineral research》2003,18(7):1326-1331
A PTH gene has been isolated from the fish Fugu rubripes. The encoded protein of 80 amino acid has the lowest homology with any of the PTH family members. Fugu PTH(1-34) had 5-fold lower potency than human PTH(1-34) in a mammalian cell system. INTRODUCTION: Parathyroid hormone (PTH) is the major hypercalcemic hormone in higher vertebrates. Fish lack parathyroid glands, but there have numerous attempts to identify and isolate PTH from fish. MATERIALS AND METHODS: Polymerase chain reaction (PCR) was performed with primers based on preliminary data from the Joint Genome Institute database. PCR amplification was performed on genomic DNA isolated from Fugu rubripes. PCR products were purified and DNA was sequenced. All sequence was confirmed from more than one independently amplified PCR product. Multiple sequence alignments were carried out, and the percentage of identities and similarities were calculated. An unrooted phylogenetic tree, using all the known PTH and PTH-related protein (PTHrP) amino acid sequences, was determined. Synthetic peptides were tested in a biological assay that measured cyclic adenosine 3',5'-monophosphate formation in UMR106.1 cells. Rabbit polyclonal antisera specific for N-terminal human PTHrP and one rabbit polyclonal antiserum specific for N terminus hPTH were used to test the cross-reactivity with fPTH(1-34) in immunoblots. 相似文献
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This study was designed to examine serum lipid profile and blood pressure in relation to age and sexual maturity. Written informed consent to participate was obtained from 42% of the eligible population of two Devon communities. The blood pressure of 343 boys and 336 girls, aged 11-16 years, was recorded and sufficient blood for analysis was obtained from 320 boys and 301 girls. Of these, sexual maturity of 221 boys and 209 girls was visually assessed using the indices developed by Tanner. In girls there was a significant (p less than 0.05) correlation between age and serum triglyceride level (r = 0.16) and in boys both serum cholesterol and HDL-cholesterol were significantly (p less than 0.01) and negatively correlated with age (r = -0.25 and -0.18 respectively). Girls had significantly higher (p less than 0.05) levels of HDL-cholesterol than boys but neither sex demonstrated significant changes (p greater than 0.05) in serum lipids or lipoproteins with sexual maturity. No significant differences (p greater than 0.05) were detected between the mean diastolic blood pressures of boys and girls but older boys had significantly higher (p less than 0.05) systolic blood pressures than similarly aged girls. Age was positively and significantly correlated (p less than 0.01) with blood pressure in both boys (systolic, r = 0.49; diastolic, r = 0.30) and girls (systolic, r = 0.28; diastolic, r = 0.29). More mature children were demonstrated to have both higher systolic and diastolic blood pressures than less mature children (p less than 0.05) but when allowance was made for school year group through analysis of co-variance the relationship for diastolic blood pressure in boys no longer remained significant. Blood pressures observed in this study do not raise general cause for concern but the data indicate that unfavourable serum lipid and lipoprotein profiles are common. 相似文献
30.