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81.
The aim of this study was to evaluate the micro-tensile bond strengths of three self-etching primer adhesive systems to normal dentin (ND), caries-affected dentin (CAD) and caries-infected dentin (CID). Human extracted molars with caries were used, and flat dentin surfaces ground by 600-grit SiC paper were prepared. The surfaces were dyed using Caries-Detector solution, treated with Clearfil SE Bond, Mac-Bond II and UniFil Bond, and then covered with resin composites according to manufacturer's instructions. After immersion in 37 degrees C water for 24 h, the teeth were serially sectioned into multiple slices. Each slice was distinguished into ND, CAD and CID groups by the degree of staining, and the bond strength was measured in a universal testing machine. Scanning electron microscopic (SEM) observation was also performed. For statistical analysis, anova and Scheffe's test were used (P < 0.05). The bond strengths of the three adhesive systems to CAD and CID were significantly lower than those to ND. There was significant difference in the bond strength to ND between Clearfil SE Bond and UniFil Bond, but no significant differences to CAD and CID among the three adhesive systems. On SEM, the hybrid layers in CAD and CID showed more porous structures compared with ND. The results indicated that the bond strengths to CAD and CID were not affected by a variety of self-etching primer adhesive systems because of the porous hybrid layer formation in carious dentin.  相似文献   
82.
五倍子水提取物去除根管内玷污层的扫描电镜观察   总被引:3,自引:0,他引:3  
目的:观察五倍子对根管内玷污层的去除效果。方法:72个离体单根牙随机分为9组,冲洗液为五倍子组(分别为200、100、50、25、12.5、6.25mg/mL)、30mL/L过氧化氢液加生理盐水组、170g/LEDTA加52.5g/LNaOCl组(阳性对照)、双蒸水组(阴性对照)。根管预备后用各冲洗液冲洗,选根中部分进行扫描电镜观察。样本分为10个区,分别评分,结果进行统计学分析。结果:170g/LEDTA加52.5g/LNaOCl组去除玷污层效果最好,但管周牙本质有过度脱矿现象。25、50、100、200mg/mL五倍子组去除玷污层的效果较好,其去除玷污层的能力随浓度增加而增大,且牙本质小管有缩小的现象,当大于50mg/mL时牙本质小管被堵塞。30mL/L过氧化氢液加生理盐水组和双蒸水组不能去除玷污层。结论:大于6.25mg/mL的五倍子水提取物有去除玷污层的作用,随浓度增大,牙本质小管缩小并出现堵塞。  相似文献   
83.
AIM: To compare using scanning electron microscopy (SEM) root canal walls following instrumentation in vitro with two different rotary NiTi instruments. The hypothesis was that no difference should be observable between the experimental groups in terms of debris on canal walls and surface morphology. METHODOLOGY: Twenty-four single-rooted human teeth were selected. Two types of NiTi instruments were used, Mtwo (Sweden & Martina, Padova, Italy) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland). Irrigation for both groups was performed after each instrument change with 5% NaOCl, 3% H2O2 and 17% EDTA solutions. Three different areas (coronal, middle and apical thirds) of the root canal were evaluated using SEM. The canal wall of each sample was assessed and compared using a predefined scale of four parameters, namely, smear layer, pulpal debris, inorganic dentine debris, surface profile. Data were analysed statistically using the Kruskal-Wallis test (anova). RESULTS: A statistically significant difference (P < 0.01) was found between the apical third and the middle and coronal thirds for both groups. No difference was observable between instrumentation groups. In the apical third canal walls were often contaminated by inorganic debris and by smear layer. In the apical third, the surface profile was affected by uninstrumented regions, comprising dentine depressions and grooves in which predentine was still visible. CONCLUSION: Both instruments produced a clean and debris-free dentine surfaces in the coronal and middle thirds, but were unable to produce a dentine surfaces free from smear layer and debris in the apical third. The presence of deep grooves and depression on dentine walls in the apical third may well explain the presence of less-instrumented areas.  相似文献   
84.

Objectives

The aim of this study was to reduce hybrid layer degradation created with simplified dentine adhesives by using two different methods to condition the dentine surface.

Methods

A smear-layer was created on flat dentine surfaces from extracted human third molars with a 180-grit/SiC-paper. Dentine specimens were conditioned before bonding with the following procedures: 37% H3PO4; H3PO4/0.5% NaOCl; 0.1 M EDTA; 0.1 M EDTA/0.5% NaOCl. Two etch-and-rinse adhesives: (Scotchbond 1XT or Optibond Solo Plus) were applied and light-cured. Composite build-ups were constructed. The bonded teeth were sectioned into beams, stored in distilled water (24 h) or 12% NaOCl solution (90 min) and finally tested for microtensile bond strengths (μTBS). Additional dentine surfaces were conditioned and bonded as previously described. They were prepared for a pulpal-micropermeability confocal microscopy study and finally observed using confocal microscopy.

Results

μTBS results revealed that both adhesives gave high bond strengths to acid-etched dentine before, but not after a 12% NaOCl challenge. Bonds made to acid-etched or EDTA-treated dentine plus dilute NaOCl, gave high μTBS that resisted 12% NaOCl treatment, as did EDTA-treated dentine alone. A confocal micropermeability investigation showed very high micropermeability within interfaces of the H3PO4, etched specimens. The lowest micropermeability was observed in H3PO4 + 0.5% NaOCl and 0.1 M EDTA groups.

Conclusions

The use of dilute NaOCl (0.5%) after acid-etching, or the conditioning of dentine smear layers with 0.1 M EDTA (pH 7.4) produced less porous resin–dentine interfaces. These dentine-conditioning procedures improve the resistance of the resin–dentine bond sites to chemical degradation (12% NaOCl) and may result in more durable resin–dentine bonds.  相似文献   
85.
Polymerization of surface active derivatives of pyrrole at the water|1,2-dichloroethane interface leads to the formation of a compact layer. New monomers have been synthesized with two pyrrole units in the molecule. Polymerization of these monomers proceeds at a lower potential and the density of the polymer layer is higher compared with monomers with one pyrrole unit in the molecule. Formation of the polymer layer has been monitored by cyclic voltammetry in the presence of transferable ions of different size and charge. Permeability of the polymer layer can be affected by the presence of a surface active derivative of cyclodextrin in the polymerization process.  相似文献   
86.
目的 探讨单吻合口胃旁路术(OAGB)治疗病态肥胖症及其相关合并症的有效性与安全性。方法 回顾性分析2018年9月至2019年10月首都医科大学附属北京友谊医院普通外科中心实施OAGB的56例肥胖病人的临床资料。结果 56例均顺利完成手术,无中转开腹病例。手术时间为78~262(131.7±30.6)min,术中失血量为20~200(45.2±50.9)mL,术后住院时间为3~7(4.4±1.1)d,每台手术所需钉仓数为5~8(6.7±0.7)个。术后6周内12例(21.4%)发生并发症,其中Clavien-Dindo分级Ⅰ级7例、Ⅱ级4例、Ⅲb级1例。术后3、6、12个月的总体重减少百分比(%TWL)分别为20.0%、26.5%及33.5%。完成术后12个月随访的25例病人中,2型糖尿病、高血压病、高脂血症及高尿酸血症的缓解率分别为100%、83.3%、91.7%及44.4%。结论 OAGB治疗病态肥胖症及其相关合并症安全且有效,术后随访应密切关注胆汁反流和营养不良风险。  相似文献   
87.
目的探讨平行重叠吻合法在3D腹腔镜右半结肠癌根治术中的应用价值。方法采用回顾性横断面研究方法。收集2016年7月至2019年7月河南省人民医院收治的138例行3D腹腔镜右半结肠癌根治术患者的临床病理资料;男83例,女55例;中位年龄为64岁,年龄范围为30~76岁。138例患者术前右半结肠肿瘤均经肠镜及病理学检查确诊为恶性肿瘤;所有患者按日本大肠癌协会第9版《大肠癌规约》进行淋巴结清扫,严格遵循无瘤原则行右半结肠切除术。观察指标:(1)手术情况。(2)术后情况。(3)随访情况。采用门诊或电话方式进行随访,了解患者生存和肿瘤复发转移情况。随访时间截至2019年9月。正态分布的计量资料以±s表示。偏态分布的计量资料以M(范围)表示。计数资料以绝对数或百分比表示。结果(1)手术情况:138例患者均行3D腹腔镜右半结肠癌根治术,消化道重建采用平行重叠吻合法,无1例中转开腹。138例患者手术时间为(151.0±54.0)min,平行重叠吻合时间为(20.1±2.0)min,术中出血量为(60±21)mL。(2)术后情况:138例患者术后首次肛门排气时间为(2.5±0.4)d,术后进食半流质食物时间为(4.0±1.3)d,手术辅助切口长度为(3.0±0.2)cm,术后并发症发生率为3.62%(5/138)。5例术后发生并发症的患者中,1例肠梗阻经胃肠减压、营养支持等保守治疗后痊愈;1例吻合口漏,经胃肠减压、局部通畅引流、控制感染、营养支持等保守治疗后痊愈;1例腹腔积液伴感染行CT引导下置管引流后痊愈;1例切口感染给予控制感染,加强换药,局部冲洗引流后痊愈;1例肺部感染,经抗感染治疗后痊愈。138例患者术后清扫淋巴结数目为(19±8)枚,术后住院时间为(7.2±4.1)d,治疗费用为(4.8±1.4)万元。138例患者术后病理学检查结果示结肠腺癌,其中低分化腺癌27例,中分化腺癌92例,高分化腺癌10例,黏液腺癌9例。(3)随访情况:138例患者中,133例获得随访,随访时间为2~38个月,中位随访时间为18个月。随访期间,2例患者死亡(1例术后16个月发现多发肝转移,术后21个月死亡;1例术后20个月发现多发肝转移,术后24个月死亡),8例出现肿瘤远处转移,其中肝转移5例,肺转移1例,腹腔转移2例,死亡及转移患者的术后病理学分期均为Ⅲ期。其余123例患者一般情况良好。结论平行重叠吻合法应用于3D腹腔镜右半结肠癌根治术中安全、有效。  相似文献   
88.
目的探讨微创Ivor-Lewis食管切除术(minimally invasive Ivor-Lewis esophagectomy,MI-ILE)治疗食管胃结合部腺癌的可行性。方法回顾性分析2018年1月~2019年6月MI-ILE治疗食管胃结合部腺癌48例资料。SiewertⅠ型11例,Ⅱ型31例,Ⅲ型6例。病灶距门齿距离(38.8±2.5)cm。结果手术时间(250.8±42.0)min,术中出血(120.3±67.0)ml。均行R0切除。27例术前新辅助治疗,26例(96%)术后病理显示部分缓解。清扫淋巴结(28.6±10.6)枚,36例淋巴结转移(8.0±5.0)枚。术后吻合口漏2例(4%),1例手术治疗,1例保守治疗,均痊愈。术后住院日(9.7±3.2)d。平均随访14个月(5~22个月),肿瘤均无复发,无死亡。结论MI-ILE治疗食管胃结合部腺癌可以保证满意的上下切缘和足够的淋巴结清扫范围,手术安全可靠。  相似文献   
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90.
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