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Novel Genetic Variants Associated With Increased Vertebral Volumetric BMD,Reduced Vertebral Fracture Risk,and Increased Expression of SLC1A3 and EPHB2 下载免费PDF全文
Carrie M Nielson Ching‐Ti Liu Albert V Smith Cheryl L Ackert‐Bicknell Sjur Reppe Johanna Jakobsdottir Christina Wassel Thomas C Register Ling Oei Nerea Alonso Edwin H Oei Neeta Parimi Elizabeth J Samelson Mike A Nalls Joseph Zmuda Thomas Lang Mary Bouxsein Jeanne Latourelle Melina Claussnitzer Kristin Siggeirsdottir Priya Srikanth Erik Lorentzen Liesbeth Vandenput Carl Langefeld Laura Raffield Greg Terry Amanda J Cox Matthew A Allison Michael H Criqui Don Bowden M Arfan Ikram Dan Mellström Magnus K Karlsson John Carr Matthew Budoff Caroline Phillips L Adrienne Cupples Wen‐Chi Chou Richard H Myers Stuart H Ralston Kaare M Gautvik Peggy M Cawthon Steven Cummings David Karasik Fernando Rivadeneira Vilmundur Gudnason Eric S Orwoll Tamara B Harris Claes Ohlsson Douglas P Kiel Yi‐Hsiang Hsu 《Journal of bone and mineral research》2016,31(12):2085-2097
Genome‐wide association studies (GWASs) have revealed numerous loci for areal bone mineral density (aBMD). We completed the first GWAS meta‐analysis (n = 15,275) of lumbar spine volumetric BMD (vBMD) measured by quantitative computed tomography (QCT), allowing for examination of the trabecular bone compartment. SNPs that were significantly associated with vBMD were also examined in two GWAS meta‐analyses to determine associations with morphometric vertebral fracture (n = 21,701) and clinical vertebral fracture (n = 5893). Expression quantitative trait locus (eQTL) analyses of iliac crest biopsies were performed in 84 postmenopausal women, and murine osteoblast expression of genes implicated by eQTL or by proximity to vBMD‐associated SNPs was examined. We identified significant vBMD associations with five loci, including: 1p36.12, containing WNT4 and ZBTB40; 8q24, containing TNFRSF11B; and 13q14, containing AKAP11 and TNFSF11. Two loci (5p13 and 1p36.12) also contained associations with radiographic and clinical vertebral fracture, respectively. In 5p13, rs2468531 (minor allele frequency [MAF] = 3%) was associated with higher vBMD (β = 0.22, p = 1.9 × 10–8) and decreased risk of radiographic vertebral fracture (odds ratio [OR] = 0.75; false discovery rate [FDR] p = 0.01). In 1p36.12, rs12742784 (MAF = 21%) was associated with higher vBMD (β = 0.09, p = 1.2 × 10–10) and decreased risk of clinical vertebral fracture (OR = 0.82; FDR p = 7.4 × 10–4). Both SNPs are noncoding and were associated with increased mRNA expression levels in human bone biopsies: rs2468531 with SLC1A3 (β = 0.28, FDR p = 0.01, involved in glutamate signaling and osteogenic response to mechanical loading) and rs12742784 with EPHB2 (β = 0.12, FDR p = 1.7 × 10–3, functions in bone‐related ephrin signaling). Both genes are expressed in murine osteoblasts. This is the first study to link SLC1A3 and EPHB2 to clinically relevant vertebral osteoporosis phenotypes. These results may help elucidate vertebral bone biology and novel approaches to reducing vertebral fracture incidence. © 2016 American Society for Bone and Mineral Research. 相似文献
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Wesely Edward Gnanaraj Johnson Marimuthu Antonisamy Mohanamathi RB Kavitha Marappampalyam Subramanian 《Asian Pacific Journal of Tropical Biomedicine》2012,2(1):1-5
Objective
To develop the reproducible in vitro propagation protocols for the medicinally important plants viz., Achyranthes aspera (A. aspera) L. and Achyranthes bidentata (A. bidentata) Blume using nodal segments as explants.Methods
Young shoots of A. aspera and A. bidentata were harvested and washed with running tap water and treated with 0.1% bavistin and rinsed twice with distilled water. Then the explants were surface sterilized with 0.1% (w/v) HgCl2 solutions for 1 min. After rinsing with sterile distilled water for 3–4 times, nodal segments were cut into smaller segments (1 cm) and used as the explants. The explants were placed horizontally as well as vertically on solid basal Murashige and Skoog (MS) medium supplemented with 3% sucrose, 0.6% (w/v) agar (Hi-Media, Mumbai) and different concentration and combination of 6-benzyl amino purine (BAP), kinetin (Kin), naphthalene acetic acid (NAA) and indole acetic acid (IAA) for direct regeneration.Results
Adventitious proliferation was obtained from A. aspera and A. bidentata nodal segments inoculated on MS basal medium with 3% sucrose and augmented with BAP and Kin with varied frequency. MS medium augmented with 3.0 mg/L of BAP showed the highest percentage (93.60±0.71) of shootlets formation for A. aspera and (94.70±0.53) percentages for A. bidentata. Maximum number of shoots/explants (10.60±0.36) for A. aspera and (9.50±0.56) for A. bidentata was observed in MS medium fortified with 5.0 mg/L of BAP. For A. aspera, maximum mean length (5.50±0.34) of shootlets was obtained in MS medium augmented with 3.0 mg/L of Kin and for A. bidentata (5.40±0.61) was observed in the very same concentration. The highest percentage, maximum number of rootlets/shootlet and mean length of rootlets were observed in 1/2 MS medium supplemented with 1.0 mg/L of IBA. Seventy percentages of plants were successfully established in polycups. Sixty eight percentages of plants were well established in the green house condition. Sixty five percentages of plants were established in the field.Conclusions
The results have shown that use of nodal buds is an alternative reproducible and dependable method for clonal propagation of A. aspera and A. bidentata. The high rate of direct shoot-root multiplication and their high rate of post-hardening survival indicate that this protocol can be easily adopted for commercial large scale cultivation. 相似文献775.
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Connectedness, maintaining active engagement with life, is crucial to successful aging. Yet, no instruments were found to measure connectedness. The purpose of this study was to develop and test a connectedness scale for older adults. A 72-item instrument was administered to 428 community-dwelling older adults. The sample was largely female, White widows/widowers, with a mean age of 76 (SD 6.95) years. The instrument was reduced to 45 items representing five factors with loadings ranging from .40 to .86. The factor labels and their reliability estimates were: (a) self-regulating (.86), (b) facing aging (.85), (c) being part of a family (.87), (d) having friends (.87), and (e) being spiritual (.88). This promising instrument may advance the science of successful aging. 相似文献
778.
Amr A. Saad Darren M. Ashcroft Kath D. Watson Deborah P. M. Symmons Peter R. Noyce Kimme L. Hyrich British Society for Rheumatology Biologics Register 《Arthritis care & research》2010,62(3):345-353
Objective
To evaluate the impact of anti–tumor necrosis factor (anti‐TNF) therapies on quality of life (QOL) and functional status in psoriatic arthritis (PsA) patients and study potential predictors for QOL improvements.Methods
The study was based on a cohort of 596 PsA patients receiving anti‐TNF therapies. Changes in functional status and QOL were assessed using the Health Assessment Questionnaire (HAQ) and Short Form 36 (SF‐36) questionnaire on a 6‐month basis. The Short Form 6D (SF‐6D) was calculated as a utility score. Univariate and multivariate linear regression models were developed to examine potential predictors of QOL improvements at 6 months, using a range of demographic, baseline disease‐specific, and therapeutic variables.Results
At 6 months, significant improvements in all SF‐36 subscale scores were found, with the greatest percentage improvement from baseline related to physical role (113.8%; 95% confidence interval [95% CI] 102.6, 125.0). The percent improvement for the physical component scale was 53.2% (95% CI 44.5, 61.9) at 6 months, whereas that for the mental component scale was 16.9% (95% CI 14.7, 19.2). The mean ± SD SF‐6D score was 0.58 ± 0.07 at baseline, and this improved to 0.63 ± 0.06 at 6 months. The median HAQ score at baseline was 1.88 (interquartile range [IQR] 1.38–2.25) for the entire cohort, and this improved to 1.25 (IQR 0.63–1.88) at 6 months. Improvements in Disease Activity Score in 28 joints at 6 months were found to be significantly associated with QOL improvements at the same time point.Conclusion
Anti‐TNF therapy is associated with improvement in both physical and mental status in PsA patients. These improvements were most substantial in patients who also had improvements in their disease activity. 相似文献779.
Nicholson TL Brockmeier SL Loving CL Register KB Kehrli ME Stibitz SE Shore SM 《Infection and immunity》2012,80(3):1025-1036
The majority of virulence gene expression in Bordetella is regulated by a two-component sensory transduction system encoded by the bvg locus. In response to environmental cues, the BvgAS regulatory system controls expression of a spectrum of phenotypic phases, transitioning between a virulent (Bvg+) phase and a nonvirulent (Bvg−) phase, a process referred to as phenotypic modulation. We hypothesized that the ability of Bordetella bronchiseptica to undergo phenotypic modulation is required at one or more points during the infectious cycle in swine. To investigate the Bvg phase-dependent contribution to pathogenesis of B. bronchiseptica in swine, we constructed a series of isogenic mutants in a virulent B. bronchiseptica swine isolate and compared each mutant to the wild-type isolate for its ability to colonize and cause disease. We additionally tested whether a BvgAS system capable of modulation is required for direct or indirect transmission. The Bvg− phase-locked mutant was never recovered from any respiratory tract site at any time point examined. An intermediate phase-locked mutant (Bvgi) was found in numbers lower than the wild type at all respiratory tract sites and time points examined and caused limited to no disease. In contrast, colonization of the respiratory tract and disease caused by the Bvg+ phase-locked mutant and the wild-type strain were indistinguishable. The Bvg+ phase-locked mutant transmitted to naïve pigs by both direct and indirect contact with efficiency equal to that of the wild-type isolate. These results indicate that while full activation of the BvgAS regulatory system is required for colonization and severe disease, it is not deleterious to direct and indirect transmission. Overall, our results demonstrate that the Bvg+ phase is sufficient for respiratory infection and host-to-host transmission of B. bronchiseptica in swine. 相似文献
780.
C Evans N Peter M Gibson EPH Torrie RB Galland TR Magee 《Annals of the Royal College of Surgeons of England》2010,92(4):347-352