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91.
Androgen receptor predominance in human ovarian carcinoma 总被引:2,自引:0,他引:2
Cytosols of 94 untreated common epithelial ovarian cancer tissues were analysed for the presence of estrogen-, progesterone- and androgen receptors. Androgen receptors clearly predominated (90%) over and above estrogen- (55%) and progesterone receptors (52%). Further characterisation particularly of the androgen receptor revealed steroid-receptor complex with the sedimentation coefficient similar to ovalbumin (3,6 S). Only androgens, natural and synthetic, were able to alter the sedimentation profile. Estrogen appeared to slightly lower the peak, while progesterone and cortisol did not alter the profile at all. No difference in receptor concentrations between tumor tissues from pre-, peri- and postmenopausal women was found. The serum hormone levels (estradiol-17 beta, testosterone, FSH, LH) measured preoperatively in 20 postmenopausal patients did not correlate with the receptor status. Majority of the ovarian carcinomas studied contained androgen receptors. We therefore suggest consideration of the addition of anti-androgens to the therapeutic strategies applicable to ovarian cancer. 相似文献
92.
A nonlinear mathematical model which incorporates both beta-cell kinetics and a glucose-insulin feedback system is proposed for describing the time variations of plasma glucose and insulin levels. Numerical simulations show that this model is consistent with experimental observations on normal groups. An analysis of the changes in the solutions with variations in the parameters showed that a decrease in a single parameter gave results consistent with experimental findings in protein-deficient (malnutrition-related) diabetes mellitus (PDDM). The model predicts that it is the function and not the number of beta cells which is reduced in PDDM. 相似文献
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In vivo fluorescence imaging uses a sensitive camera to detect fluorescence emission from fluorophores in whole-body living small animals. To overcome the photon attenuation in living tissue, fluorophores with long emission at the near-infrared (NIR) region are generally preferred, including widely used small indocarbocyanine dyes. The list of NIR probes continues to grow with the recent addition of fluorescent organic, inorganic and biological nanoparticles. Recent advances in imaging strategies and reporter techniques for in vivo fluorescence imaging include novel approaches to improve the specificity and affinity of the probes and to modulate and amplify the signal at target sites for enhanced sensitivity. Further emerging developments are aiming to achieve high-resolution, multimodality and lifetime-based in vivo fluorescence imaging. 相似文献
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M. Bhushana Reddy S. Sailaja K. Vemasevana Raju C. Nageswara Raju P. Giridhar B. Vengala Rao B. Sudhakar Reddy 《Luminescence》2011,26(6):680-684
Rare earth ions (Eu3+ or Tb3+)‐activated Ca3 Ga2 Si3O12 (CaGaSi) phosphors were synthesized by using a sol–gel method. Photoluminescence spectra of Eu3+:CaGaSi phosphors exhibited five emission bands at 578, 592, 612, 652 and 701 nm, which were assigned to the transitions (5D0 → 7F0, 7F1, 7F2, 7F3 and 7F4), respectively, with an excitation wavelength of λexci = 392 nm. Among these, the transition 5D0 → 7F2 (612 nm) displayed bright red emission. In the case of Tb3+:CaGaSi phosphors, four emission bands were observed at 488 (5D4 → 7F6), 543 (5D4 → 7F5), 584 (5D4 → 7F4) and 614 nm (5D4 → 7F3) from the measurement of PL spectra with λexci = 376 nm. Among these, the transition 5D4 → 7F5 at 543 nm displayed bright green emission. The structure and morphology of the phosphors were studied from the measurements of X‐ray diffraction (XRD), scanning electron microscopy (SEM) and energy‐dispersive X‐ray analysis (EDAX) results. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
98.
Locus Heterogeneity for Waardenburg Syndrome is Predictive of Clinical Subtypes 总被引:1,自引:4,他引:1 下载免费PDF全文
Lindsay A. Farrer Kathleen S. Arnos James H. Asher Clinton T. Baldwin Scott R. Diehl Thomas B. Friedman Jacquie Greenberg Kenneth M. Grundfast Christopher Hoth Anil K. Lalwani Barbara Landa Kate Leverton Aubrey Milunsky Robert Morell Walter E. Nance Valerie Newton Rajkumar Ramesar Valluri S. Rao Jennifer E. Reynolds Theresa B. San Agustin Edward R. Wilcox Ingrid Winship Andrew P. Read 《American journal of human genetics》1994,55(4):728-737
Waardenburg syndrome (WS) is a dominantly inherited and clinically variable syndrome of deafness, pigmentary changes, and distinctive facial features. Clinically, WS type I (WS1) is differentiated from WS type II (WS2) by the high frequency of dystopia canthorum in the family. In some families, WS is caused by mutations in the PAX3 gene on chromosome 2q. We have typed microsatellite markers within and flanking PAX3 in 41 WS1 kindreds and 26 WS2 kindreds in order to estimate the proportion of families with probable mutations in PAX3 and to study the relationship between phenotypic and genotypic heterogeneity. Evaluation of heterogeneity in location scores obtained by multilocus analysis indicated that WS is linked to PAX3 in 60% of all WS families and in 100% of WS1 families. None of the WS2 families were linked. In those families in which equivocal lod scores (between −2 and +1) were found, PAX3 mutations have been identified in 5 of the 15 WS1 families but in none of the 4 WS2 families. Although preliminary studies do not suggest any association between the phenotype and the molecular pathology in 20 families with known PAX3 mutations and in four patients with chromosomal abnormalities in the vicinity of PAX3, the presence of dystopia in multiple family members is a reliable indicator for identifying families likely to have a defect in PAX3. 相似文献
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Jin CH Krishnaiah M Sreenu D Subrahmanyam VB Rao KS Mohan AV Park CY Son JY Sheen YY Kim DK 《Bioorganic & medicinal chemistry letters》2011,21(20):6049-6053
A series of 1-substituted-3-(6-methylpyridin-2-yl)-4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)pyrazoles 14a-ae, 16a, 16b, and 21a-c has been prepared and evaluated for their ALK5 inhibitory activity in an enzyme assay and in a cell-based luciferase reporter assay. The 4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-N-(4-methoxyphenyl)-3-(6-methylpyridin-2-yl)-1H-pyrazole-1-carbothioamide (14n) inhibited ALK5 phosphorylation with IC(50) value of 0.57 nM and showed 94% inhibition at 100 nM in a luciferase reporter assay using HaCaT cells permanently transfected with p3TP-luc reporter construct. 相似文献