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Facial skeletal changes following hypertelorbitism correction 总被引:4,自引:0,他引:4
J B Mulliken L B Kaban C A Evans R D Strand J E Murray 《Plastic and reconstructive surgery》1986,77(1):7-16
This is a retrospective study of skeletal changes in 19 patients with corrected hypertelorism. A favorable outcome, defined as relapse less than 5 mm, occurred in patients with an average interorbital distance of 32 mm, whereas patients with an average interorbital distance of 40 mm tended to relapse over 5 mm. Neither age, interorbital configuration, nor diagnosis affected the stability of orbital translocation. At last evaluation (mean 6.7 years postoperatively), the mean interorbital distance was 22.4 mm in the favorable outcome group and 28.3 mm in the unfavorable category. This study suggested that the standard hypertelorism operation may interfere with anterior facial growth. Unless psychosocial factors predominate in a child with mild deformity, repair should be postponed until late adolescence. In a young child with gross telorbitism, nasoethmoidal resection and transmaxillary osteotomies or facial bipartition is justified. Another long-term skeletal problem was resorption of the reconstructed nasal complex. Technical and biological explanations for this are given. The correction of hypertelorism is surgery of the nose and of the midface. 相似文献
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D B Snead A Weltman J Y Weltman W S Evans J D Veldhuis M M Varma C D Teates E A Dowling A D Rogol 《Journal of applied physiology》1992,72(6):2149-2156
We examined the relationships among reproductive hormone concentrations and bone mineral density (BMD) in 43 women runners classified as eumenorrheic (n = 24), oligomenorrheic (n = 8), or amenorrheic (n = 11). Results were compared with a eumenorrheic nonrunner control group (n = 11). Serum 17 beta-estradiol, progesterone, and dehydroepiandrosterone sulfate concentrations were determined in daily blood samples for 21 days, and integrated concentrations (areas under the curve) were calculated. BMD was assessed at the lumbar spine and proximal femur by dual-photon absorptiometry. As expected, 17 beta-estradiol, progesterone, and lumbar spine BMD were higher in the control and eumenorrheic runner groups than in the oligomenorrheic and amenorrheic runner groups (P less than 0.05). Progesterone concentration was significantly correlated with lumbar spine BMD in the eumenorrheic runners (r = 0.61). None of the steroid hormones was significantly related to BMD in the oligomenorrheic/amenorrheic group. The present data suggest that circulating levels of gonadal steroid hormones affect axial BMD in eumenorrheic runners. 相似文献
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Correlation between NMR spectral parameters of nucleosides and its implication to the conformation about the glycosyl bond 总被引:1,自引:0,他引:1
Analyses of high resolution proton and carbon NMR spectra of a series of guanine nucleosides in DMSO have revealed a near linear correlation between the chemical shift of the H2, atom of the sugar moiety and the vicinal coupling constant 3JC4-H1'. This unexpected result provides evidence that the variations in the glycosyl torsion angle between nucleosides in solution are less that those which have previously been reported in crystals and it is an experimental basis for analyzing the syn and anti populations from chemical shift and coupling constant data. 相似文献
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D B Evans M Thavarajah J A Kanis 《Biochemical and biophysical research communications》1991,175(3):795-803
Recent studies have demonstrated homology between bone-derived growth factor and beta 2 microglobulin. We have shown that beta 2 microglobulin has proliferative actions on human bone-derived cells in vitro and that these cells also show immunogenicity for beta 2 microglobulin. beta 2 microglobulin stimulated the incorporation of 3H-thymidine into DNA of human bone cells in a dose-dependent manner. In contrast to this stimulatory action, beta 2 microglobulin had no detectable activity with the same concentration on the production of osteocalcin, alkaline phosphatase activity or prostaglandin E2 synthesis. The possibility that the human bone-derived cells could also produce beta 2 microglobulin was examined. Under basal conditions these cells exhibit immunoreactivity for beta 2 microglobulin, the expression of which could be enhanced following treatment with interferon gamma in a dose-dependent manner. The co-localization of staining for beta 2 microglobulin and alkaline phosphatase, a marker of the osteoblast phenotype, indicate that human osteoblast-like cells represent a source of activity of this factor. The production of beta 2 microglobulin by human osteoblast-like cells and the subsequent action of this factor on cells within the bone microenvironment may indicate a role for beta 2 microglobulin as a local regulator of bone metabolism. 相似文献
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The relative rates of biosynthesis of cardenolide and sapogenin steroids of Digitalis purpurea were estimated by their uptake of 14CO2. The incorporation of label into both groups, although initially slow, indicated that biosynthesis occurs even at the end of the growing season. The sapogenins were produced more rapidly than the cardenolides at this stage of plant development. Within the group of sapogenins, digitogenin, the trihydroxy compound, was produced at a greater rate than the dihydroxy steroid gitogenin. In the case of the cardenolides, the trihydroxy gitoxigenin was produced at a slower rate than the dihydroxy digitoxigenin. 相似文献