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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
目的:探讨PDCA在缩短肺功能患者等候时间中的作用。方法:通过调取2018年3月19~4月19日肺功能工作量与2017年同期对比,查找患者等候时间长的原因。结果:通过完善绩效考核体系、设定基础工作量、加强科室内部协调等措施,有效缩短了患者等候时间,提高了工作效率。结论:通过PDCA循环,不仅缩短了患者等候时间和呼吸科平均住院日,还提高了患者满意度,使科室内部合作更加协调与紧密。  相似文献   
2.
Objective:In-stent restenosis (ISR) after stenting for intracranial stenosis is a significant issue. This study aimed to evaluate the usefulness of the 3D T1-SPACE technique in the follow-up of patients after stent implantation.Methods:Fifteen patients with intracranial arterial stenosis were prospectively enrolled 6–8 months after stenting. Digital subtraction angiography (DSA) and 3D T1-SPACE imaging were performed to evaluate the degree of stenosis and the enhancement of the vessel wall. Bland–Altman plots were used to assess the agreement between the two imaging methods, and the Pearson correlation coefficient was calculated as a measure of the linear correlation.Results:Eight Enterprise stents and seven Wingspan stents were used in 15 patients. The follow-up DSA after 6–8 months showed that the degree of stenosis was 40% (range, 30–72%), and ISR occurred in 4 of 15 (26.7%) lesions. The degree of stenosis assessed using the 3D T1-SPACE imaging technique was 35% (range, 30–75%). All four patients with ISR demonstrated significant enhancement. The Pearson correlation coefficient between the two methods was 0.959 (p < 0.05), and the Bland–Altman plot showed that all data points were within the consistency limits ( x- ± 1.96 s).Conclusion:As a non-invasive imaging modality, 3D T1-SPACE showed great consistency with DSA in measuring the degree of stenosis after intracranial stenting. It may be used as an optional method for detecting ISR.Advances in knowledge:This study evaluated the usefulness of 3D T1-SPACE technique in the follow-up of patients after stent implantation, which could be used as an optional and non-invasive method in detection of in-stent restenosis.  相似文献   
3.
Facilitated ion transfer (FIT) and simple ion transfer (IT) reactions at the water|1,2-dichloroethane (W|DCE) interface with media of low ionic strength are investigated by employing micro- and nano-pipettes. The model systems chosen for the FIT and IT are K+ transfer facilitated by dibenzo-18-crown-6 (DB18C6) and tetramethylammonium (TMA+), respectively. For the FIT reaction at micro- and submicro-liquid|liquid interfaces, when the supporting electrolyte concentrations in the organic phase are at micromolar levels, its voltammetric waves are analyzed by the theory for one-electron oxidation of uncharged species in organic solution with little added supporting electrolyte on solid ultramicroelectrodes (UMEs) proposed by Oldham [K.B. Oldham, J. Electroanal. Chem. 250 (1988) 1]. Its chronoamperograms are strongly affected by the externally applied potentials, which is consistent with the theory proposed by Stojek and co-workers [A. Jaworski, M. Donten, Z. Stojek, Anal. Chim. Acta 305 (1995) 106, A. Jaworski, M. Donten, Z. Stojek, J. Electroanal. Chem. 407 (1996) 75, W. Hyk, M. Palys, Z. Stojek, J. Electroanal. Chem. 415 (1996) 13, W. Hyk, Z. Stojek, J. Electroanal. Chem. 422 (1997) 179] for reactions at solid UMEs with different concentrations of supporting electrolyte. In addition, the FIT reaction can exhibit well-defined steady-state waves at the nano-liquid|liquid interface when no supporting electrolyte is added to the organic phase. For the TMA+ transfer reaction from the aqueous phase to DCE (or from DCE to the aqueous phase), the magnitude of its steady-state limiting current depends on the concentration of supporting electrolyte in the same phase, and the shape and position of its transfer waves are influenced by the supporting electrolyte concentrations in the adjacent phase. We can observe clearly the migration effect on the transfer reaction of charged species.  相似文献   
4.
6 000 年前成人第三磨牙的研究   总被引:1,自引:0,他引:1  
目的:观察距今约6 000年前成人第三磨牙的位置情况。方法:研究了200个半坡博物馆内保存的新石器时代人颌骨标本,第三磨牙共383颗(上颌187颗,下颌196颗),观察第三磨牙的萌出情况。第三磨牙未萌出者经X线片证实,按有无第三磨牙牙胚,将其分别归为埋伏阻生组或先天缺失组。结果:上颌第三磨牙先天缺失率为26.74%,下颌第三磨牙先天缺失率为17.35%。上颌第三磨牙阻生率为2.67%,下颌第三磨牙阻生率为14.79%。结论:现代人第三磨牙阻生率与先天缺失率均较新石器时代成人高,人类第三磨牙阻生与先天缺失是伴随整个人类进化而发生的咀嚼器官退化现象的一部分。  相似文献   
5.
GP-084泡沫硅橡胶和SY-1硅橡胶之间粘结性能的测定   总被引:1,自引:0,他引:1  
目的:评价GP-084泡沫硅橡胶和SY-1硅橡胶之间的粘结性能。方法:分别测试有无Adhesive-AGP-084泡沫硅橡胶和SY-1硅橡胶之间的粘结强度;并采用电镜观察2种材料之间的粘结界面。结果:使用Adhesive-AGP-084泡沫硅橡胶和SY-1硅橡胶之间的粘结强度为(1.31±0.09)MPa,无Adhesive-AGP-084泡沫硅橡胶和SY-1硅橡胶之间的粘结强度为(1.29±0.11)MPa,2组测试结果的差异无统计学意义;电镜观察2种材料之间没有明显界面,完全融合在一起。结论:GP-084泡沫硅橡胶和SY-1硅橡胶2种材料之间具有良好的粘结效果,可以完全融合在一起,无明显界面形成。  相似文献   
6.
目的建立下颌第二恒磨牙及其牙周膜、牙槽骨的分析用模型。方法应用CAE软件3D MAX6.0及CATIA4.0生成磨牙及其牙周组织的三维有限元模型,利用HYPERMESH划分网格,生成可分析的三维有限元实体模型。结果建立了下颌第二恒磨牙及其牙周膜、牙槽骨的三维有限元模型,可以分别进行受力状态下应力、应变的分析。结论该模型可供口腔正畸矫治中磨牙的受力分析应用。  相似文献   
7.
梁绍  谭光琦 《当代医学》2021,27(32):95-97
目的 探讨微创经皮肾镜取石术对输尿管上段结石患者清除效果及尿流动力学的影响.方法 选取2018年1月至2019年12月本院收治的100例输尿管上段结石患者,依据随机数表法分为两组,各50例.对照组予以输尿管钬激光碎石手术,观察组予以微创经皮肾镜取石术.比较两组手术指标、结石清除效果以及尿流动力学改善情况.结果 两组手术时间比较差异无统计学意义;与对照组比较,观察组术中出血量少于对照组,住院时间短于对照组,差异有统计学意义(P<0.05);观察组结石清除率为94.00%,高于对照组的76.00%,差异有统计学意义(P<0.05);观察组最大尿流率及最大尿道压力(MUP)均高于对照组,差异有统计学意义(P<0.05).结论 输尿管上段结石患者采用微创经皮肾镜取石术治疗效果显著,可有效减少术中出血量、缩短住院时间,提升结石清除率,改善尿流动力学指标,值得临床推广.  相似文献   
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Background

Mechanical thrombectomy is a promising new modality of interventional stroke treatment. Preparation of thrombus is a very important step for the evaluation of the mechanical thrombectomy devices. The objective of this study was to explore a new method of thrombus preparation with fluid model (FM) for assessment of thrombectomy devices used in the recanalization of acute ischemic stroke.

Methods

Elongation test and catheter injection test were used to evaluate the mechanical properties of thrombi prepared by FM and static model (SM). Histological structures of two artificial clots and specimens of stroke patients were compared. Radiopacity of thrombus made by FM was evaluated in a swine embolization model.

Results

The maximum tensile length of thrombi prepared by FM and SM were significantly higher (4.28 ± 0.23 cm vs 3.16 ± 0.13 cm, P < 0.01) and showed less breakage on catheter injection test (13% vs 60%, P < 0.05). Histological features of thrombi prepared by FM showed mixed thrombus structure, similar to thromboemboli retrieved from acute stroke patients, while clots generated by SM were replete with erythrocytes. A total of twelve vessels in two swine were successfully occluded (TIMI 0 or 1), with sufficient radiopacity of each injected thrombus.

Conclusion

The thrombus prepared by FM had good mechanical stability, sufficient radiopacity, and similar histological structure of thromboemboli retrieved from stroke patients, which make it possible to be used in the evaluation of thrombectomy devices.  相似文献   
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