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71.
Evaluation of formocresol versus ferric sulphate primary molar pulpotomy: a systematic review and meta-analysis 总被引:1,自引:0,他引:1
AIM: To present a systematic review of the effects of formocresol and ferric sulphate when used as medicaments in pulpotomized primary molar teeth. METHODOLOGY: The study list was obtained by using MEDLINE, the Cochrane Library, EMBASE and SCI search. Only those papers which met the inclusion criteria were accepted. The quality of studies used for meta-analysis was assessed by a series of validity criteria according to Jadad's scale. A systematic review and meta-analysis were performed. RESULTS: Eleven clinical studies comprising four randomized-clinical trials (RCTs), four controlled clinical trials (CCTs) and three retrospective studies were included. The results of the meta-analysis of six prospective clinical trials suggested that the two popular pulpotomy medicaments were not significantly different in terms of clinical outcomes, radiographic findings, prevalence of apical and furcal destruction, internal root resorption or pulp canal obliteration. The relative risk (RR) value and 95% CI for those parameters were 0.72 (0.43-1.23), 0.87 (0.59-1.30), 0.67 (0.27-1.66), 1.77 (0.56-5.58) and 1.41 (0.63-3.15), respectively. The overall clinical and radiographic success rates based on the data of treatments with ferric sulphate from the 11 studies included ranged from 78% to 100% (mean 91.6 +/- 8.15%) and from 42% to 97% (mean 73.5 +/- 18.40%), respectively. CONCLUSIONS: In primary molar teeth with exposure of vital pulps by caries or trauma, pulpotomies performed with either formocresol or ferric sulphate have similar clinical and radiographic success. Ferric sulphate may be recommended as a suitable replacement for formocresol. 相似文献
72.
目的:评价流动复合树脂作为洞衬材料在楔状缺损修复中的价值。方法:选择85例患者的360颗楔状缺损患牙为研究对象,采用自身对照设计,随机选择每例患者一侧患牙为实验组,采用流动树脂衬洞后再以复合树脂充填;对侧同名牙为对照组,直接采用复合树脂充填。以改良的USPHS/Ryge临床修复体质量评估系统评价修复后1年和3年的疗效。应用SPSS12.0软件包对数据进行统计学处理。结果:实验组在边缘完整性和术后敏感方面优于对照组,有显著性差异。在边缘完整性方面,1年复查时实验组满意率为100%,高于对照组的95.65%(P<0.01);3年复查时实验组满意率为98.56%,高于对照组的92.42%(P<0.01),均有统计学差异。术后1年复查时,实验组未出现敏感病例,而对照组6颗患牙出现中度敏感,需要更换修复体。实验组优于对照组,差异有统计学意义(P<0.05)。结论:流动复合树脂洞衬用于楔状缺损修复可提高边缘完整性和降低术后敏感发生率。 相似文献
73.
74.
目的本文通过对安氏Ⅲ类错的家庭聚集性、遗传度及遗传方式的研究,探讨遗传因素在安氏Ⅲ类错发生中的地位和作用。方法采用遗传流行病学病例对照的研究方法,对195个安氏Ⅲ类错先证家系和208个对照家系进行调查,比较其一级亲属患病率,以二项分布(p+q)n的数学模型及χ2检验判定家庭聚集性。以Falconer回归法进行遗传度的估算。结果安氏Ⅲ类错先证组一级亲属患病率为27.83%,与对照组8.09%相比,统计学上差异具有显著性。二项分布显示,先证组实际频数大于二项分布的理论频数,说明其具有家庭聚集性。一级亲属遗传度为80.85%,其中男性遗传度为90.79%,高于女性遗传度(71.08%)。结论安氏Ⅲ类错的发生具有明显的家庭聚集性,属于多基因遗传模式。其一级亲属遗传度为80.85%,遗传倾向有明显的性别差异。遗传因素在其发病中起重要作用,尤其对男性作用更为明显。 相似文献
75.
Qian Wang Gang Yu Xue-dong Zhou Ove A. Peters Qing-hua Zheng Ding-ming Huang 《Journal of endodontics》2011,37(8):1063-1068
Introduction
The aim of this study was to evaluate the radiographic features of permanent three-rooted mandibular first molars with radix entomolaris (RE), investigate the correlation between anatomical classification and radiographic type of RE, and to determine the most effective horizontal beam angulation for the diagnosis of RE.Methods
Twenty-five extracted mandibular first permanent molars with RE were selected for taking radiographs in 7 horizontal angulations. By using set criteria, 3 evaluators assessed morphologic and radiographic features of the RE and optimum beam angulation for RE diagnosis. Intraexaminer variability was analyzed with Cohen kappa test.Results
Three types of curvature of RE presented with 3 distinct types of typical radiographic appearance on orthoradial radiographs. We classified the radiographic features of RE into 3 types, as follows: type i, type ii, and type iii. Seven teeth showed type i radiographic features. Zero-degree, 5-degree, 15-degree, and 25-degree radiographs were significantly better than the mesially angulated -15-degree and -25-degree images for detecting the type i RE images (P < .05). Fifteen-degree, 25-degree, and -25-degree horizontal beam angulations showed significantly more accurate diagnoses of RE in 8 type ii images (P < .05). Only 25-degree-angled radiographs were found to have a high diagnostic yield of type iii RE images (P < .05). A significant correlation was found between morphologic and radiographic types of RE (P < .05, contingency coefficient = 0.473). Intraexaminer variability was low, with kappa = 0.68 (P < .05).Conclusions
RE presents 3 types of typical radiographic features on orthoradial radiographs. Additional 25-degree mesial horizontal-angled radiographs are essential for preoperative identification and evaluation of RE, especially types ii and iii. 相似文献76.
In Asia, a round face rather is more acceptable than a square face. Intraoral mandibular angle ostectomy is a common aesthetic procedure for correcting a prominent mandibular angle. However, an operation of sheer straight-lined prominent mandibular angle resection would sometimes create extramandibular angles or palpable bone steps in the margin of mandibular body and produce unnatural lower one-third facial appearance, especially for a square and disproportional mandibular angle even extending to the middle mandibular body. This article describes the method of multistage mandibular angle ostectomy to produce a natural lower one-third facial contour. This method mainly focused on the posterior area of mandibular ostectomy by intraoral approach, although it has modifications. Mandibular contouring is realized first through bone cutting from antegonial notch posteriorly upperward, reaching to the middle ramus of the mandible near the earlobe; second ostectomy followed along mandible lower part is to get rid of extramandibular angle according to the preoperative design; sometimes necessarily, third ostectomy creates a smooth mandibular contour. From January 2000 to January 2010, 379 patients were operated on, and satisfactory results were achieved. Thus, this procedure could avoid excessive bone cutting, extramandibular angles, unnatural appearance, and palpable bone steps. 相似文献
77.
目的:建立下颌前牙不同程度牙槽骨吸收后的釉质、牙本质、牙骨质、牙周膜、松质骨、皮质骨等组织的三维有限元模型。方法:利用薄层CT扫描技术与Ansys软件相结合,对层厚为1mm的CT断层影像进行分析处理。结果:模型具有良好的几何相似性,共有单元约13万个,节点约19万个,数据量约130MB,可以根据要求任意旋转、缩放、透视、剖开,进行多种方式观察;并可以按照不同研究目的和要求,对模型进行简单的修改和调整,模拟牙槽骨吸收、联冠修复等临床治疗所需的几何形态,考查各种约束和加载条件下前牙的力学反应;讨论了约束的处理和载荷的施加方式。结论:薄层CT扫描技术与Ansys软件相结合建立的三维有限元模型,能较精确地模拟实际情况,为进一步研究下颌前牙牙槽骨吸收和联冠修复奠定了良好的基础。 相似文献
78.
复方绞股蓝对金地鼠颊囊癌前病变的疗效观察 总被引:2,自引:1,他引:2
本实验采用DMBA(二甲基苯丙蒽)丙酮局部涂抹法成功地建立了金地鼠颊囊癌前病变的动物模型。与此同时应用复方绞股蓝进行了对口腔粘膜癌前病变阻断的实验研究。结果显示:绞股蓝对口腔粘膜癌前病变的阻断部位发生在均质型白斑到颗粒状白斑或疣状白斑阶段。先服绞股蓝后涂DMBA组优于边涂边服组。实验证明绞股蓝具有防癌和抗癌功能,在口腔粘膜癌前病变的防治中具有应用前景,其抗癌机理还有待于作更深入的研究。 相似文献
79.
本文将多功能粘结剂和复合树脂应用于86例牙体缺损的修复并进行术后两年的随访复查,成功率达92.3%,依据病损的不同类型统计学上有显著差异。 相似文献
80.
Fei Li Yong Chen Meiqin Zhang Ping Jing Zhao Gao Yuanhua Shao 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2005,579(1):89-102
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