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1.
目的符合透析治疗安全的透析用水是血液透析日常治疗开展的基本保障,根据统计分析内毒素含量的变化规律,探索控制透析用水内毒素含量的管理方式。方法对上海市21家血液净化中心(室)2019年3月至2020年2月期间透析用水的内毒素(endotoxin,ET)含量数据进行汇总与统计分析。结果透析用水内毒素含量在全年的春季与夏季中会存在部分偏高的情况,其中春季送检的样本中,ET含量>0.25 EU/ml比例占当季送检样本的0.57%,ET含量在0.03~0.25EU/ml之间的比例占7.34%;在夏季送检的样本中,ET含量>0.25EU/ml比例占当季送检样本的1.13%,ET含量在0.03~0.25EU/ml之间的比例占3.39%,与秋冬两季水平相比,差异有统计学意义(F=11.392,P值<0.001)。结论严格管控透析用水生产、输送过程的每个环节,规范采样流程、加强反渗机日常维护管理、重视水处理系统及配管的日常消毒等措施可减少血液透析相关的不良反应发生,提高患者透析质量。  相似文献   
2.
《Dental materials》2020,36(2):257-269
ObjectivesTo assess the release and apical extrusion of toxic volatile compounds and disinfection by-products during instrumentation and irrigation of artificially infected root canal specimens, with sodium hypochlorite and ethylene diamine tetra acetic acid.MethodsForty-two single-rooted human teeth were decoronated to obtain 15 mm-long root specimens and working length was determined 1 mm short of root apex. All specimens were initially preflared, to create sufficient conical space for the development of a nutrient-stressed multispecies biofilm. The specimens were randomly assigned into three groups [Group 1; no endodontic intervention, Group 2; instrumentation with rotary files and irrigation with sterile saline, Group 3; instrumentation with rotary files and irrigation with 2.5% sodium hypochlorite (NaOCl) and 17% ethylene diamine tetra acetic acid (EDTA)]. A customised experimental model apparatus was fabricated for each specimen. The apical root third was inserted in a glass vial filled with sterile ultrapure water, to simulate high-compliance periradicular space. The reaction products of the aliquots obtained from the glass vials were analysed in real time, by selected ion flow tube mass spectrometry (SIFT-MS) in triplicates. Two-way analysis of variance (ANOVA) with post hoc Tukey tests were used for data analysis. The level of statistical significance was set at P < 0.05.ResultsThe group of teeth that were not subjected to endodontic intervention did not show any volatile compounds (VOCs) or disinfection by products (DBPs) whilst instrumentation and irrigation of root canals (Groups 2 and 3) resulted in the apical extrusion of VOCs and DBPs. In Group 3, the aliquots obtained from periradicular space released high concentrations of methanol, propanol, ammonia, chloroform, together with unexpected higher levels of formaldehyde, which were statistically significant compared to Group 2 (P < 0.05).SignificanceThe mechanical preparation and irrigation of artificially infected root canals with rotary files, 2.5% NaOCl and 17% EDTA resulted in the formation of toxic VOCs and DBPs in a water-closed periradicular space. The chemical interaction of NaOCl and EDTA resulted in the generation of high concentrations of formaldehyde. The formation of chloroform and formaldehyde indicate that risk assessment of the potential hazards to health should be carried out.  相似文献   
3.
目的探讨消毒供应室采用全程质控管理模式进行干预对护理管理质量以及预防医院感染的影响作用。方法于该院2017年1-12月期间内接收的患者中选取117例作为对照组,此期间消毒供应室未实施全程质控管理。另于该院2018年1-12月期间内接收的患者中选取105例作为观察组,此期间消毒供应室实施全程质控管理。对比两组患者医院感染发生率以及消毒供应室满意率,并观察手术科室对消毒供应室工作人员工作质量评价情况。结果观察组医院感染发生率较对照组更低,且消毒供应室满意率较对照组更高;观察组清洗质量、器械处理、物品包装、环境监测评分较对照组均更高;差异有统计学意义(P<0.05)。结论全程质控管理可有效提高消毒供应室护理管理质量,降低医院感染事件发生率,临床实用价值较高。  相似文献   
4.
5.
AimTo assess the efficacy of disinfection of caries-effected dentin (CAD) using KTP laser and different decontamination methods using ozonated water (OW), Rose Bengal photosensitizer (RBP), chlorhexidine (CHX), and Er, YAG laser on the shear bond strength (SBS) of adhesive resin bonded to deciduous teeth.Material and methodsA total of 50 extracted and radiographically verified carious primary molars were collected and scrutinized according to ICDAS criteria. Specimens were allocated randomly into five groups (n = 10) as per the type of CAD disinfectants. KTP laser, OW, RBP, CHX (control), and Er, YAG laser. After cavity sanitization, a resin adhesive (prime and bond NT) was smeared on the dentinal exterior followed by incremental composite filling. SBS evaluation was performed by employing specimens in the universal testing machine. The debonded surface was assessed under 40x magnification in a stereomicroscope to ascertain fracture mode. Statistical analysis was done by using the ANOVA and the Post Hoc Tukey multiple comparison tests (p < 0.05).ResultsThe highest SBS was exhibited by group 2 i.e., when OW was employed for CAD disinfection (10.25 ± 0.24 MPa). Whereas, the lowest SBS bond value was unveiled by samples in group 3 when RBP was applied for dentin surface sanitization (7.85 ± 0.59 MPa).CAD disinfection with KTP laser (8.25 ± 0.41 MPa), CHX (8.19 ± 0.73 MPa), and RBP displayed comparable bond values (p > 0.05).ConclusionOzonated water and Er, YAG laser could be employed as cavity disinfectants in primary teeth as they demonstrated better shear bond strength without jeopardizing the adhesive binding capacity of restorative resins bonded to caries-affected dentin.  相似文献   
6.
7.

Objective

This study evaluated the clinical effectiveness of two exposure times of microwave irradiation on the disinfection of complete dentures.

Methods

Biofilm samples were collected from dentures of 30 patients, who were randomly divided into two experimental groups of 15 subjects each: Group 1—patients had their maxillary denture microwaved for 3 min (650 W); Group 2—patients had their maxillary denture microwaved for 2 min (650 W). Denture biofilm samples were taken with swabs, before (left side surfaces) and after (right side surfaces) microwave irradiation. All microbial material was plated on selective media for Candida spp., Staphylococcus spp., mutans streptococci and a non-selective media. After incubation (48 h/37 °C), the number of colony-forming units (cfu/mL) was counted. Microorganisms which grew on selective media were identified using biochemical methods. The data were statistically analyzed by Kruskal–Wallis test, followed by Dunn's post-test (α = 0.05).

Results

Microwave irradiation for 3 min (Group 1) resulted in sterilization of all dentures evaluated. After microwave irradiation for 2 min (Group 2), a significant decrease in Candida spp. (P = 0.0062), Staphylococcus spp. (P = 0.0178), mutans streptococci (P = 0.0047) and non-identified species (P < 0.0001) was achieved in comparison with the cfu/mL obtained before irradiation. The colonies grown after 2 min of microwave irradiation were identified as Candida albicans, non-aureus Staphylococci and Streptococcus mutans.

Conclusion

Microwave irradiation for 3 min may be a potential treatment to prevent cross-contamination.  相似文献   
8.
不同消毒剂对藻酸钾印模表面细菌消毒效果比较   总被引:1,自引:0,他引:1  
目的 使用不同消毒剂浸泡消毒污染口腔印模,观察其消毒效果。方法 实验组81个试件按所染菌种分为金黄色葡萄球菌组,血液链球菌组,白色念珠菌组,每组27个试件。各菌组再按消毒剂不同分三组。每组9个试件。用250ml无菌蒸馏水冲洗后分别浸没于2%强化中性戊二醛,0.1%碘伏,0.5%次氯酸中,于5min。10min,15min各取出3个试件。阳性对照组,每组6个试件。分别染菌后3个试件冲洗,3个试件不冲。阴性对照组,每组2个试件。取印模后不染菌。各组浸于中和液中,洗下余菌。培养并计数。结果 ①冲洗可以使印模表面的附着菌数平均减少95.15%。②2%戊二醛消毒5min对三种菌的消毒效果可达100%。0.1%碘伏浸泡消毒5min对三种菌的消毒效果可达99.99%。0.5%次氯酸消毒10min可达到消毒效果。结论 ①冲洗可以部分去除印模表面附着菌。但迭不到消毒的效果,仍应对印模进行消毒处理。②2%戊二醛消毒5min,0.1%碘伏,0.5%次氯酸消毒10min对沾染白色念珠菌。金黄色葡萄球菌,血链球菌的印模可达到消毒效果。  相似文献   
9.

Objective:

The aim of this study was to evaluate the degree of microbial contamination in packaged gutta-percha cones before and during use in clinical conditions.

Material and Methods:

Sealed packages of #15-40 gutta-percha cones were opened under aseptic laboratory conditions. Two gutta-percha cones from each size were randomly drawn and added to tubes containing glass beads and 750 μL of saline. The tubes were vortexed, serially diluted and samples of 250 μL were cultured on agar plates. The plates were incubated at 37°C for 3 days and colonies were counted. The initially sampled packages were distributed to 12 final year dental students. The packages were collected at the end of the first and the third clinical practice days and sampled as described above.

Results:

Baseline microbial counts did not exceed 3 CFU. At the end of the first and the third day, additional contamination was found in five and three of the packages, respectively. The ratio of contaminated packages at the first day and the third day was not significantly different (z-test; p > 0.05). The numbers of microorganisms cultured at the first day (8 ± 9.9 CFU) and the third day (4.5 ± 8.3 CFU) were not significantly different (Wilcoxon signed-rank test; p > 0.05). No significant correlation was found between the number of filled root canals and cultured microorganisms at either the first day (Spearman''s rho; r = 0.481, p = 0.113) or the third day (r = -0.034, p = 0.917).

Conclusions:

Gutta-percha cones taken directly from manufacturer''s sealed package harbored microorganisms. Clinical use of the packages has been found to be associated with additional contamination of the gutta-percha cones. The counts of cultured microorganisms did not correlate well with the number of filled root canals.  相似文献   
10.
目的:观察氢氧化钙碘仿糊剂运用于有窦型慢性根尖周脓肿根管内封药消毒的临床效果。方法:选择在同一牙列上有二颗磨牙均患有窦型慢性根尖周脓肿的病例50例,共100颗患牙。将同一病例的二颗患牙分别设为实验组和对照组,同时进行根管治疗。实验组(50颗牙)采用氢氧化钙碘仿糊剂根管内封药消毒,对照组(50颗牙)采用氢氧化钙糊剂根管内封药消毒,对两组根管消毒效果进行临床观察和比较。结果:实验组74%(37/50)封药1次后即可行根管充填术,对照组52%(26/50)封药1次后可行根管充填术,两组间封药1次的根管充填率存在显著性差异(P<0.05)。实验组平均封药次数为1.30次,对照组平均封药次数为1.56次。结论:用氢氧化钙碘仿糊剂根管内封药消毒能够减少有窦型慢性根尖周脓肿根管封药消毒的次数,有利于窦道的尽快愈合。  相似文献   
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