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991.
Lizbeth E. García-Velázquez Samuel Canizales-Quinteros Sandra Romero-Hidalgo Adriana Ochoa-Morales Leticia Martínez-Ruano Carla Márquez-Luna Víctor Acuña-Alonzo M. Teresa Villarreal-Molina M. Elisa Alonso-Vilatela Petra Yescas-Gómez 《Neurogenetics》2014,15(1):13-17
Spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant disease characterized by progressive cerebellar ataxia and macular degeneration causing progressive blindness. It accounts for 1 to 11.6 % of spinocerebellar ataxias (SCAs) cases worldwide and for 7.4 % of SCA7 cases in Mexico. We identified a cluster of SCA7 families who resided in a circumscribed area of Veracruz and investigated whether the high incidence of the disease in this region was due to a founder effect. A total of 181 individuals from 20 families were studied. Four microsatellite markers and one SNP flanking the ATNX7 gene were genotyped and the ancestral origin and local ancestry analysis of the SCA7 mutation were evaluated. Ninety individuals from 19 families had the SCA7 mutation; all were found to share a common haplotype, suggesting that the mutation in these families originated from a common ancestor. Ancestral origin and local ancestry analysis of SCA7 showed that the chromosomal segment containing the mutation was of European origin. We here present evidence strongly suggesting that the high frequency of SCA7 in Veracruz is due to a founder effect and that the mutation is most likely of European origin with greatest resemblance to the Finnish population. 相似文献
992.
Bryann B. DeBeer Nathan A. Kimbrel Eric C. Meyer Suzy B. Gulliver Sandra B. Morissette 《Psychiatry research》2014
Rates of suicide are alarmingly high in military and veteran samples. Suicide rates are particularly elevated among those with post-traumatic stress disorder (PTSD) and depression, which share overlapping symptoms and frequently co-occur. Identifying and confirming factors that reduce, suicide risk among veterans with PTSD and depression is imperative. The proposed study evaluated, whether post-deployment social support moderated the influence of PTSD–depression symptoms on, suicidal ideation among Veterans returning from Iraq and Afghanistan using state of the art clinical, diagnostic interviews and self-report measures. Operations Enduring and Iraqi Freedom (OEF/OIF) Veterans (n=145) were invited to, participate in a study evaluating returning Veterans? experiences. As predicted, PTSD–depression, symptoms had almost no effect on suicidal ideation (SI) when post-deployment social support was high; however, when, post-deployment social support was low, PTSD–depression symptoms were positively associated with, SI. Thus, social support may be an important factor for clinicians to assess in the context of PTSD and, depressive symptoms. Future research is needed to prospectively examine the inter-relationship, between PTSD/depression and social support on suicidal risk, as well as whether interventions to, improve social support result in decreased suicidality. 相似文献
993.
Seth D. Friedman PhD Sandra L. Poliachik PhD Randolph K. Otto MD Gregory T. Carter MD Christopher B. Budech BA Thomas D. Bird MD Daniel G. Miller MD PhD Dennis W.W. Shaw MD 《Muscle & nerve》2014,49(2):257-260
Introduction: Magnetic resonance imaging of muscle shows short tau‐inversion recovery (STIR) brightness in autosomal dominant facioscapulohumeral muscular dystrophy (FSHD1) suggestive of active inflammation/injury. We measured the longitudinal stability/progression of this potential disease biomarker. Methods: Nine subjects underwent calf MRI imaging over 2 years. Two radiologists evaluated qualitative muscle changes. Results: In 3/9 subjects, calf muscles demonstrated moderate/severe STIR hyperintensity at Time 1 that had progressed to fatty replacement 2 years later (Time 2). In the remaining subjects, moderate/severe muscle STIR abnormalities, when present, were consistent between exams. Mild STIR+ elevations had roughly similar patterns between exams. Conclusions: Moderate/severe STIR hyperintensities often foreshadow fatty replacement over a 2‐year interval. Whether longer time courses are required to observe muscle degeneration and fatty replacement in some subjects remains to be explored. Muscle Nerve 49 : 257–260, 2014 相似文献
994.
Sandra Perez da Rosa Christopher Paul Millward Muhammad Imran Bhatti Andrew Healey Sasha Clare Burn Ajay Sinha 《Child's nervous system》2014,30(5):891-895
Introduction
Cephalocele is a relatively rare cranial dysraphism characterised by herniation of intracranial structures through the skull. Surgical management is primarily necessary where a risk of infection through communication of the lesion with the intracranial space exists, a risk of rupture, or for cosmetic purposes. Cephalocele is often associated with venous anomalies such as vertical embryonic positioning of the straight sinus, splitting of the superior sagittal sinus, vein of Galen elongation, along with tenting of the tentorium [Morioka et al. Childs Nerv Syst 25:309–315, 2009]Patients
Here, we report four cases of cephalocele with pre-operative MRI imaging retrospectively studied, demonstrating associated venous anomalies. Three of these patients went on to have uncomplicated, corrective surgery, while one was managed conservatively.Results
All four cases demonstrated the main venous drainage going through a persistent falcine sinus to drain into the superior sagittal sinus. Upward tenting of the tentorium was observed in three cases (cases 1, 3 and 4). Two of our cases demonstrated other venous anomalies frequently reported in the literature, namely splitting of the superior sagittal sinus and absence of the transverse sinus (case 1) and communication of the cephalocele with the superior sagittal sinus and absence of the straight sinus (case 2).Conclusion
The association between cephalocele and venous anomalies suggests that pre-operative MRI should be mandatory for a full evaluation of a suspicious midline cranial lesion in order to evaluate the safety of corrective surgery. 相似文献995.
996.
Alessandra Carriero Elizabeth A Zimmermann Adriana Paluszny Simon Y Tang Hrishikesh Bale Bjorn Busse Tamara Alliston Galateia Kazakia Robert O Ritchie Sandra J Shefelbine 《Journal of bone and mineral research》2014,29(6):1392-1401
The multiscale hierarchical structure of bone is naturally optimized to resist fractures. In osteogenesis imperfecta, or brittle bone disease, genetic mutations affect the quality and/or quantity of collagen, dramatically increasing bone fracture risk. Here we reveal how the collagen defect results in bone fragility in a mouse model of osteogenesis imperfecta (oim), which has homotrimeric α1(I) collagen. At the molecular level, we attribute the loss in toughness to a decrease in the stabilizing enzymatic cross‐links and an increase in nonenzymatic cross‐links, which may break prematurely, inhibiting plasticity. At the tissue level, high vascular canal density reduces the stable crack growth, and extensive woven bone limits the crack‐deflection toughening during crack growth. This demonstrates how modifications at the bone molecular level have ramifications at larger length scales affecting the overall mechanical integrity of the bone; thus, treatment strategies have to address multiscale properties in order to regain bone toughness. In this regard, findings from the heterozygous oim bone, where defective as well as normal collagen are present, suggest that increasing the quantity of healthy collagen in these bones helps to recover toughness at the multiple length scales. © 2014 American Society for Bone and Mineral Research. 相似文献
997.
Cortical Porosity Identifies Women With Osteopenia at Increased Risk for Forearm Fractures 下载免费PDF全文
Yohann Bala Roger Zebaze Ali Ghasem‐Zadeh Elizabeth J Atkinson Sandra Iuliano James M Peterson Shreyasee Amin Åshild Bjørnerem L Joseph Melton III Helena Johansson John A Kanis Sundeep Khosla Ego Seeman 《Journal of bone and mineral research》2014,29(6):1356-1362
Most fragility fractures arise among the many women with osteopenia, not the smaller number with osteoporosis at high risk for fracture. Thus, most women at risk for fracture assessed only by measuring areal bone mineral density (aBMD) will remain untreated. We measured cortical porosity and trabecular bone volume/total volume (BV/TV) of the ultradistal radius (UDR) using high‐resolution peripheral quantitative computed tomography, aBMD using densitometry, and 10‐year fracture probability using the country‐specific fracture risk assessment tool (FRAX) in 68 postmenopausal women with forearm fractures and 70 age‐matched community controls in Olmsted County, MN, USA. Women with forearm fractures had 0.4 standard deviations (SD) higher cortical porosity and 0.6 SD lower trabecular BV/TV. Compact‐appearing cortical porosity predicted fracture independent of aBMD; odds ratio (OR) = 1.92 (95% confidence interval [CI] 1.10–3.33). In women with osteoporosis at the UDR, cortical porosity did not distinguish those with fractures from those without because high porosity was present in 92% and 86% of each group, respectively. By contrast, in women with osteopenia at the UDR, high porosity of the compact‐appearing cortex conferred an OR for fracture of 4.00 (95% CI 1.15–13.90). In women with osteoporosis, porosity is captured by aBMD, so measuring UDR cortical porosity does not improve diagnostic sensitivity. However, in women with osteopenia, cortical porosity was associated with forearm fractures. © 2014 American Society for Bone and Mineral Research. 相似文献
998.
999.
1000.
Sandra van Brunschot Paul Fockens Olaf J. Bakker Marc G. Besselink Rogier P. Voermans Jan-Werner Poley Hein G. Gooszen Marco Bruno Hjalmar C. van Santvoort 《Surgical endoscopy》2014,28(5):1425-1438