全文获取类型
收费全文 | 399篇 |
免费 | 20篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 3篇 |
基础医学 | 24篇 |
口腔科学 | 6篇 |
临床医学 | 22篇 |
内科学 | 23篇 |
皮肤病学 | 5篇 |
神经病学 | 7篇 |
特种医学 | 17篇 |
外科学 | 140篇 |
综合类 | 55篇 |
预防医学 | 43篇 |
眼科学 | 18篇 |
药学 | 32篇 |
中国医学 | 9篇 |
肿瘤学 | 22篇 |
出版年
2024年 | 3篇 |
2023年 | 14篇 |
2022年 | 24篇 |
2021年 | 28篇 |
2020年 | 14篇 |
2019年 | 11篇 |
2018年 | 20篇 |
2017年 | 8篇 |
2016年 | 10篇 |
2015年 | 13篇 |
2014年 | 27篇 |
2013年 | 20篇 |
2012年 | 22篇 |
2011年 | 31篇 |
2010年 | 21篇 |
2009年 | 23篇 |
2008年 | 12篇 |
2007年 | 15篇 |
2006年 | 18篇 |
2005年 | 17篇 |
2004年 | 17篇 |
2003年 | 10篇 |
2002年 | 5篇 |
2001年 | 7篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 3篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1995年 | 5篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有432条查询结果,搜索用时 15 毫秒
411.
目的:探讨一期后前路联合松解矫形治疗胸腰椎陈旧骨折伴后凸畸形的临床疗效。方法:2005年6月~2010年10月收治21例胸腰椎陈旧骨折伴后凸畸形患者,男13例,女8例,年龄23~61岁,平均37.6岁。均为单节段骨折,角状后凸顶点:T11 1例,T12 7例,L1 8例,L2 5例;后凸Cobb角23°~59°,平均38.6°。均有严重腰背痛症状,术前VAS评分为7.1~10(7.6±2.1)分。9例伴有神经功能障碍,术前Frankel分级:B级2例,C级2例,D级5例;其中4例合并括约肌功能障碍。2例曾行单纯椎板减压手术,10例曾行椎板减压内固定术。术前CT显示关节突骨性融合14例,骨折椎体前方有骨赘及骨桥形成16例。均采用一期后前路联合松解、减压、前路椎体间植骨、内固定术治疗。随访观察患者临床症状及影像学改善情况。结果:手术均顺利完成,手术时间150~310min,平均200min;术中失血量400~1200ml,平均650ml。术中、术后无一例出现严重并发症。患者均获随访,随访时间12~60个月,平均21.3个月,腰背痛症状均明显缓解,VAS评分改善至1.5~2.6(2.1±0.4)分;后凸角明显改善,末次随访时后凸Cobb角为5°~23°(11.1°±5.8°),与术前比较差异有统计学意义(P<0.05),平均矫正率为71.3%。植骨节段均骨性融合,融合时间平均4.3个月。9例有神经功能障碍者术后8例有不同程度恢复,4例括约肌功能障碍者3例改善。结论:一期后前路联合松解、减压、矫形治疗胸腰椎陈旧骨折伴后凸畸形手术安全,能早期重建脊柱稳定性,效果满意。 相似文献
412.
目的对重度僵硬性脊柱侧凸矫正技术的进展进行综述。方法查阅近年来国内外重度僵硬性脊柱侧凸的相关文献,总结重度僵硬性脊柱侧凸矫正技术的最新进展。结果重度僵硬性脊柱侧凸矫正技术有如下进展:Halo-重力牵引应用增多;尝试了后路矫形术中应用Halo-股骨髁上牵引;全椎弓根螺钉固定矫形技术逐步得到推广;经后路全脊椎切除技术、一期前后路手术及单纯后路矫形手术应用增多。结论各种矫形技术的进展显显著提高了重度僵硬性脊柱侧凸的矫形效果,但目前尚无标准化治疗方案,未来可期待更显著的进展。 相似文献
413.
《Dental materials》2020,36(8):e255-e265
Statement of problemMeasurement of irradiance passing through a dental restoration for properly curing a dual- or light-polymerized luting composite is imprecise due to surface reflection.ObjectiveTo provide a mathematical correction of measured transmitted irradiance for predicting true transmitted light intensity through CAD/CAM restorations.MethodsA total of 432 specimens were fabricated. Seven modern CAD/CAM resin-based composites (RBCs) and one CAD/CAM glass-ceramic (control group) were sectioned and polished into specimens of 0.5–5 mm thickness (in 0.5 mm steps, n = 6). Irradiance of a violet-blue LED light curing unit (LCU) (power modes: Standard, High and Plasma) was measured after passing through each specimen with a spectrometer. Data was compared based on 95% confidence intervals and using univariate ANOVA followed by Tukey HSD (α = 0.05).ResultsThe measured transmitted irradiance passing through the specimens decreased exponentially. Significantly highest values of transmitted irradiance were measured for 0.5 mm thick specimens for all materials (p < 0.05). The decadic absorption coefficient for CAD/CAM-RBCs ranged from 0.292 mm−1 to 0.387 mm−1 while the control group (glass-ceramic) reached a significantly lower value of 0.283 mm−1. The reflection ratio for all materials ranged from 12.6% to 18.5%.SignificanceA correction can be implemented to predict the true transmitted irradiance after passing through a dental restoration as function of initial irradiance, specimen thickness and material specific parameters. For a practitioner, this model may be applied depending on the specific treatment conditions, the individual LCU's radiant emittance and restoration thickness for the tested materials. 相似文献
414.
McIntyre C Derrick Roberts AL Ranieri E Clements PR Byers S Anson DS 《Molecular genetics and metabolism》2008,93(4):411-418
Mucopolysaccharidosis type IIIA (MPS IIIA) is a heritable glycosaminoglycan (GAG) storage disorder which is characterised by lysosomal accumulation of heparan sulphate, secondary to a deficiency of sulphamidase (heparan-N-sulphatase, N-sulphoglucosamine sulphohydrolase, EC No. 3.10.1.1.). There is currently no treatment for affected individuals who experience progressive CNS deterioration prior to an early death.As a first step towards developing gene therapy as a treatment for MPS IIIA, an MPS IIIA mouse model was used to examine the efficacy of intravenous lentiviral-mediated gene therapy. Five-week-old mice were injected with virus expressing murine sulphamidase and analysed 6 months after treatment. Transduction by the lentiviral vector was highest in the liver and spleen of treated animals, and sulphamidase activity in these tissues averaged 68% and 186% of normal, respectively.Storage was assessed using histochemical, chemical and mass spectrometric analyses. Storage in most somatic tissues was largely normalised, although chondrocytes were an obvious exception. Histologically, improvement of lysosomal storage within the brain was variable. However, β-hexosaminidase activity, which is abnormally elevated in MPS IIIA, was significantly reduced in every treated tissue, including the brain. Total uronic acid was also significantly reduced in the brains of treated mice. The level of a disaccharide marker (hexosamine-N-sulphate[α-1,4]hexuronic acid; HNS-UA) of heparan sulphate storage was also decreased in the brains of treated mice, albeit non-significantly.These results suggest that lentiviral-mediated somatic gene transfer may affect not only the somatic, but possibly also the CNS pathology, found in MPS IIIA. 相似文献
415.
Sjoerd B. Vos Caroline Micallef Frederik Barkhof Andrea Hill Gavin P. Winston Sebastien Ourselin John S. Duncan 《Journal of neuroradiology. Journal de neuroradiologie》2018,45(6):368-373
T2-FLAIR is the single most sensitive MRI contrast to detect lesions underlying focal epilepsies but 3D sequences used to obtain isotropic high-resolution images are susceptible to motion artefacts. Prospective motion correction (PMC) – demonstrated to improve 3D-T1 image quality in a pediatric population – was applied to high-resolution 3D-T2-FLAIR scans in adult epilepsy patients to evaluate its clinical benefit. Coronal 3D-T2-FLAIR scans were acquired with a 1 mm isotropic resolution on a 3 T MRI scanner. Two expert neuroradiologists reviewed 40 scans without PMC and 40 with navigator-based PMC. Visual assessment addressed six criteria of image quality (resolution, SNR, WM-GM contrast, intensity homogeneity, lesion conspicuity, diagnostic confidence) on a seven-point Likert scale (from non-diagnostic to outstanding). SNR was also objectively quantified within the white matter. PMC scans had near-identical scores on the criteria of image quality to non-PMC scans, with the notable exception that intensity homogeneity was generally worse. Using PMC, the percentage of scans with bad image quality was substantially lower than without PMC (3.25% vs. 12.5%) on the other five criteria. Quantitative SNR estimates revealed that PMC and non-PMC had no significant difference in SNR (P = 0.07). Application of prospective motion correction to 3D-T2-FLAIR sequences decreased the percentage of low-quality scans, reducing the number of scans that need to be repeated to obtain clinically useful data. 相似文献
416.
目的建立一种能够准确测定7-氨基头孢烷酸中有关物质的方法,同时进行不同方法生产的产品的含量测定及有关物质检查。方法采用高效液相色谱法。使用C18色谱柱(SB-C18,5μm,4.6mm×250mm);以磷酸盐缓冲液(取5g磷酸氢二钾和5g磷酸二氢钾溶解于1000m L水中,用磷酸调节流动相p H值至6.0)—乙腈(92:8)为流动相;检测波长为254nm;柱温为35℃;进样量20μL。结果 7-氨基头孢烷酸在504~0.02534μg/m L范围内,线性关系良好,相关系数R2为0.9991;去乙酰7-氨基头孢烷酸在10.52~0.0263μg/m L范围内,线性关系良好,相关系数R2为0.9996;去乙酰氧7-氨基头孢烷酸在9.66~0.02415μg/m L范围内,线性关系良好,相关系数R2为0.9998;头孢菌素C在10.5~0.02625μg/m L范围内,线性关系良好,相关系数R2为0.9998。溶液的稳定性及进样精密度、日内精密度、重复性、专属性良好。去乙酰7-氨基头孢烷酸、去乙酰氧7-氨基头孢烷酸和头孢菌素C的校正因子分别为0.80、0.82、1.67。结论此方法可以准确测定7-氨基头孢烷酸中的含量,并采用校正因子法计算有关物质的含量。不同方法生产的7-氨基头孢烷酸的含量及有关物质无明显差异。 相似文献
417.
418.
419.
420.
王清任一生的医学贡献凝聚于一册薄薄的《医林改错》,其构建的脏腑理论模型具有生理学与病理学的双重含义,具体可分为“气血运行模型”和“水谷运化模型”。前者侧重于病理探讨,生理描述亦多,可细分为“气运模块”与“血运模块”;后者常见于生理阐释,病理描述甚少,可细分为“水运模块”与“谷运模块”。“气运模块”的生理功能以存储和运行元气、津液为主,其病理变化以津液失常和气虚为主;“血运模块”的生理功能以存储和运行血液为主,其病理变化以血瘀为主;“水运模块”的生理功能主以运行水液,“谷运模块”的生理功能主以运化谷物,二者的病理变化均较少涉及。 相似文献