全文获取类型
收费全文 | 8172篇 |
免费 | 730篇 |
国内免费 | 463篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 35篇 |
妇产科学 | 74篇 |
基础医学 | 459篇 |
口腔科学 | 831篇 |
临床医学 | 616篇 |
内科学 | 396篇 |
皮肤病学 | 33篇 |
神经病学 | 215篇 |
特种医学 | 202篇 |
外科学 | 354篇 |
综合类 | 1428篇 |
预防医学 | 375篇 |
眼科学 | 39篇 |
药学 | 2937篇 |
9篇 | |
中国医学 | 1223篇 |
肿瘤学 | 120篇 |
出版年
2024年 | 10篇 |
2023年 | 126篇 |
2022年 | 171篇 |
2021年 | 245篇 |
2020年 | 263篇 |
2019年 | 233篇 |
2018年 | 208篇 |
2017年 | 219篇 |
2016年 | 236篇 |
2015年 | 223篇 |
2014年 | 505篇 |
2013年 | 559篇 |
2012年 | 649篇 |
2011年 | 662篇 |
2010年 | 523篇 |
2009年 | 450篇 |
2008年 | 429篇 |
2007年 | 505篇 |
2006年 | 482篇 |
2005年 | 438篇 |
2004年 | 335篇 |
2003年 | 285篇 |
2002年 | 192篇 |
2001年 | 193篇 |
2000年 | 138篇 |
1999年 | 113篇 |
1998年 | 89篇 |
1997年 | 85篇 |
1996年 | 101篇 |
1995年 | 87篇 |
1994年 | 74篇 |
1993年 | 79篇 |
1992年 | 58篇 |
1991年 | 55篇 |
1990年 | 38篇 |
1989年 | 51篇 |
1988年 | 31篇 |
1987年 | 37篇 |
1986年 | 20篇 |
1985年 | 36篇 |
1984年 | 23篇 |
1983年 | 17篇 |
1982年 | 20篇 |
1981年 | 14篇 |
1980年 | 16篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1977年 | 9篇 |
1976年 | 9篇 |
1974年 | 5篇 |
排序方式: 共有9365条查询结果,搜索用时 31 毫秒
1.
李朝清 《实用中西医结合临床》2022,22(18)
目的: 探讨银杏叶制剂联合地塞米松在老年突聋治疗中对血清炎症指标的影响。方法: 按随机数字表法将我院2016年7月-2021年7月收治的102例老年突聋患者分入两组(各51例)。对照组用地塞米松治疗,治疗组加用银杏叶制剂治疗。观察两组治疗前后纯音听阈和血管内皮功能指标[超氧化物歧化酶(SOD)、脂质过氧化物(LPO)、一氧化氮(NO)]、血清炎症指标[肿瘤坏死因子-α(TNF-α)、C反应蛋白(CRP)、白细胞介素-6(IL-6)],分析其疗效与不良反应。结果: 与对照组比较,治疗组总有效率更高(96.08%vs 82.35%)(χ2=4.993,P=0.025);两组治疗后各频率点阈值均下降,且相比对照组,治疗组治疗后各频率点阈值更低(P<0.05);治疗后两组SOD、NO水平均升高,LPO水平降低(P<0.05),且相比对照组,治疗组治疗后SOD、NO水平更高,LPO水平更低(P<0.05);治疗后两组血清TNF-α、CRP、IL-6水平降低,且相比对照组,治疗组TNF-α、CRP、IL-6水平更低(P<0.05);治疗组不良反应发生率5.88%,对照组为9.80%,两组比较差异无统计学意义(P=0.543,χ2=0.461)。结论: 银杏叶制剂联合地塞米松治疗老年突聋患者疗效理想,能恢复各频率点听力,安全可靠,推测改善患者血管内皮功能和炎症因子水平是其重要作用机制。 相似文献
2.
3.
《Saudi Dental Journal》2021,33(7):518-523
ObjectiveOptimal tooth reduction is a key requirement for aesthetics, function, and the longevity of fixed restorations. Research has demonstrated that controlled and conservative tooth preparation is crucial for the long-term success of adhesive restorations. Different techniques of fabricating reduction guides have been previously reported in literature. The present technical note describes the fabrication technique and clinical application of a customized metal preparation reduction guide.Material and methodPatient presented with tilted maxillary left central incisor. The flared-out part of the tooth was modified prior to veneer restoration preparation. Resin pattern reduction guide was fabricated on the diagnostic cast with a window on the tilted mesial portion of the tooth. After intraoral evaluation, resin pattern guide was casted. Metal reduction guide was place intraorally and reduction was provided on the exposed surface of the tooth. After the removal of the tilted portion, a harmonious arch form allowed the clinician to provide adequate evaluation and preparation for veneer restorations.ResultsThe device demonstrated good practical value, allowing for selective and controlled reduction of tooth structure, and definitive protection of adjacent tooth surfaces from iatrogenic damage. The clinical outcome successfully addressed the patient’s restorative and aesthetic needs, and the veneer was stable 2 years postoperatively.ConclusionUse of a metal guide assists clinicians to provide a more predictable reduction of a desired tooth surface, while decreasing the risk of compromising the other/adjacent tooth surfaces. 相似文献
4.
5.
目的:建立高效液相色谱-串联质谱法测定雷公藤制剂中雷公藤甲素、雷公藤内酯酮、雷公藤晋碱、雷公藤次碱和雷公藤红素的含量。方法:采用电喷雾正电离模式和多反应监测模式。雷公藤甲素、雷公藤内酯酮、雷公藤晋碱和雷公藤次碱含量测定,以含5 mmol·L-1碳酸氢铵的水溶液和纯甲醇作为流动相,采用梯度洗脱方式在ACE UltraCore SuperPhenylHexyl(2.1 mm×50.0 mm,5 μm)色谱柱上进行分离。雷公藤红素含量测定,以含0.5%甲酸的水溶液和含0.1%甲酸的乙腈作为流动相,采用等度洗脱在ACE Excel C18-AR(2.1 mm×50.0 mm,5 μm)色谱柱上进行分离。结果:雷公藤甲素、雷公藤内酯酮、雷公藤晋碱、雷公藤次碱和雷公藤红素分别在2.4~1 200,2.0~1 000,80~40 000,80~40 000和10~5 000 ng·mL-1范围内线性关系良好,平均加样回收率分别为 94.56%,102.36%,93.27%,95.67%和99.82%,RSD均低于5.13%。结论:本方法运行时间短,灵敏度高,精密度和重复性好,适用于雷公藤制剂中雷公藤甲素、雷公藤内酯酮、雷公藤晋碱、雷公藤次碱和雷公藤红素5种活性成分定量检测,可为雷公藤制剂多指标质量控制提供实验依据。 相似文献
6.
目的:探讨胆汁槟榔维B1胶囊联合复方聚乙二醇电解质散在电子肠镜检查前肠道准备中的应用效果。方法:选取2017年1月至2017年12月来我院行电子肠镜检查的180例病人为研究对象,并随机等分为A、B、C三组,A组病人于肠镜检查前6 h口服3盒复方聚乙二醇电解质散;B组病人于肠镜检查前1 d口服胆汁槟榔维B1胶囊;C组患者在检查前1 d口服胆汁槟榔维B1胶囊,并于肠镜检查前6 h口服3盒复方聚乙二醇电解质散。比较三组病人的排便次数、肠道清洁效果、肠道清洁范围、气泡量及不良反应发生情况。结果:C组病人肠道清洁效果、肠道清洁范围、气泡产生量显著优于A、B组,差异具有统计学意义(P<0.05),肠道清洁效果与气泡产生量A组与B组差异无统计学意义(P>0.05);排便次数B、C组少于A组(P<0.05),且B组少于C组,差异有统计学意义(P<0.05);不良反应发生情况B组低于A、C组(P<0.05),A组与C组差异无统计学意义(P>0.05)。结论:胆汁槟榔维B1胶囊联合复方聚乙二醇电解质散行肠道准备可明显提高肠道清洁效果、肠道清洁范围、降低气泡产生量,并且不良反应发生率不高于单独使用复方聚乙二醇电解质散,能够取得更加满意的肠道准备效果,可在肠镜检查前肠道准备中广泛推广。 相似文献
7.
8.
Surgical site infections (SSIs) impact significantly on patient mortality, morbidity and quality of life. They also incur financial costs on the healthcare system, although the total cost may vary depending on the severity of the infection. Antisepsis, aseptic technique and skin preparation are important concepts in the preventative strategies to reduce the risks of SSIs. This article reviews these concepts and the role they play in the patient's perioperative journey. 相似文献
9.
10.
《Journal of endodontics》2020,46(11):1726-1732
IntroductionThe aim of the present study was to evaluate the morphologic changes on the apical foramen and the formation of dentinal microcracks after foraminal enlargement in straight and curved root canals using scanning electron microscopic (SEM) and micro–computed tomographic (micro-CT) analyses.MethodsSixty teeth were selected and divided into 2 experimental groups: GI (incisors/straight group, n = 30) and GM (molars/curved group, n = 30). Each group was divided into 2 subgroups (n = 15) according to the analysis performed: SEM or micro-CT analysis. The incisors and mesiobuccal canal of molars were instrumented with Reciproc Blue R25 instruments (VDW, Munich, Germany) using standardized shaping procedures in the apical foramen and 1 mm beyond. The occurrence of foraminal deformation was analyzed by scanning electron microscopy. The z test was used for statistical analysis (P < .05). Micro-CT imaging was used to observe the presence of microcracks in the root apical third. Afterward, pre- and postoperative cross-sectional images were screened to identify the presence of dentinal defects.ResultsThe curvature of the canal did not influence the occurrence of foraminal deformation either for instrumentation in the foramen or for instrumentation beyond the foramen (P > .05). It was also observed that the increase in the working length did not influence the appearance of new deformations in the GI/SEM and GM-SEM groups (P > .05). Qualitative micro-CT analysis showed the presence of dentinal defects in 0.8% (112) and 1.5% (208) of the cross sections of incisors and molars, respectively, from a total of 13,987 slices. All dentinal defects identified in the analysis of any postoperative scans were already present in the corresponding preoperative images. Therefore, no new microcracks were observed after root canal preparation.ConclusionsThe preparation of straight and moderately curved root canals with Reciproc Blue, regardless of the working length, did not influence the occurrence of apical foramen deformations and did not cause the formation of dentinal microcracks. 相似文献