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《Journal of endodontics》2022,48(4):479-486
IntroductionAsepsis in endodontics aims to control all potential sources of infection. Inadvertent introduction of bacteria into the root canal system may occur when the aseptic chain is breached during treatment. Therefore, measures are taken to prevent such microbial access and establish an aseptic environment. This study aimed to assess potential bacterial contamination and the potential risk of iatrogenic introduction from 7 sites comprising surfaces, instruments, and files acquired during the treatment of 30 vital, pulpitic teeth.MethodsBacterial samples were collected from access burs, files, endodontic rulers, rubber dam surfaces, gloves, and instruments. Genomic DNA was extracted and quantified by quantitative polymerase chain reaction. Bacterial types were determined using next-generation sequencing.ResultsHigh frequencies of contamination and microbial numbers were encountered in all sample types examined.Thirty-eight percent of the initial files introduced into the root canal had significant levels of bacteria at the point of obturation, including endodontic pathogens. Around half of the rubber dam surfaces were contaminated with substantial bacterial loads at the time of obturation, and bacteria were also detected in 20%–30% of gloves, instruments, and rulers before obturation. Next-generation sequencing revealed the predominant oral or endodontic origin of these contaminants, with the following genera identified: Streptococcus, Rothia, Granulicatella, Cutibacterium, Corynebacterium, Peptostreptococcus, and Fusobacterium. Together, these findings highlight the potential risk of reintroducing endodontically relevant bacteria during treatment.ConclusionsGloves, rubber dams, instruments, and files acquire bacterial contamination during treatment at high frequencies and loads. This highlights the potential risk of iatrogenic contamination at the clinically vulnerable point of canal obturation. Measures to address these may improve clinical outcomes.  相似文献   
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目的:观察左炔诺孕酮宫内缓释系统联合戈舍瑞林治疗子宫内膜不典型增生(AEH)患者的效果。方法:回顾性分析2019年10月至2020年10月该院收治的86例AEH患者的临床资料,根据治疗方案不同分为观察组和对照组各43例。对照组应用戈舍瑞林治疗,观察组在对照组基础上联合左炔诺孕酮宫内缓释系统治疗,比较两组子宫内膜厚度、月经失血图(PBAC)评分、性激素[促黄体生成素(LH)、促卵泡生成素(FSH)、雌二醇(E2)]水平、肿瘤相关因子水平、临床疗效和不良反应发生率。结果:治疗后,观察组子宫内膜厚度、PBAC评分及LH、FSH、E2、血清人附睾蛋白4(HE4)和血管内皮生长因子(VEGF)水平均低于对照组,差异有统计学意义(P<0.05);观察组治疗总有效率为97.67%,明显高于对照组的81.40%,差异有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:左炔诺孕酮宫内缓释系统联合戈舍瑞林治疗AEH患者可提高治疗总有效率,降低子宫内膜厚度、PBAC评分、LH、FSH、E2和肿瘤相关因子水平,效果优于单纯戈舍瑞林治疗。  相似文献   
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目的:研究活血复健汤的作用机理及其在缺血性脑卒中(CIS)治疗中的应用价值。方法:将某院收治的56例CIS患者随机分为X组和X+H组各28例,分别行单纯西药治疗、西药+活血复健汤治疗。于两组患者治疗前后,采用美国国立卫生研究院卒中量表对患者的神经功能进行评价,评价临床干预有效率,并检测血清hs-CRP、IL-6、TNF-α。结果:X+H组患者美国国立卫生研究院卒中量表评分要比X组低(P<0.05),X+H组患者临床干预有效率为92.86%,高于X组的75%(P<0.05);X+H组患者血清hs-CRP、IL-6、TNF-α均低于X组(P<0.05)。结论:在常规西药治疗的基础上联合活血复健汤治疗能进一步提高治疗效果,改善神经功能及机体炎症反应。  相似文献   
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A delayed haemolytic transfusion reaction (DHTR) encompasses a positive direct antiglobulin test (DAT) developed anytime between 24 hours to 28 days after cessation of transfusion, a positive eluate or a newly identified alloantibody in the plasma or serum along with features of haemolysis in the patient. Routinely, it is expected that with the transfusion of one unit of packed red cells in a patient of average height and weight, the haemoglobin level and hematocrit increase by 1 g/dL and 3% respectively. However, in a patient with DHTR, an inadequate rise of post-transfusion haemoglobin (< 1 g/dL) or rapid fall in haemoglobin back to pre-transfusion levels is observed. Kidd antibodies are particularly known to cause DHTR, maybe alone or in unison with other antibodies. Detection of these alloantibodies is consequential in providing good transfusion support to these patients. These events may be difficult to detect as they may present as varied clinical features or immunological nuisances. In this case series, we have presented three cases of DHTR with special emphasis on their clinical presentations, immunohaematological evaluations, laboratory parameters and the role of proper transfusion support in these patients to avoid further complications.  相似文献   
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目的:观察炎可宁联合氧氟沙星治疗急性化脓性中耳炎患儿的效果。方法:回顾性分析2017年10月至2019年10月该院收治的78例急性化脓性中耳炎患儿的临床资料,根据治疗方案不同将其分为对照组和研究组各39例。对照组给予氧氟沙星滴耳液治疗,研究组在对照组基础上联合炎可宁片治疗,比较两组临床疗效、治疗前后T细胞亚群指标水平、炎性因子水平、病原清除率、听力阈值和不良反应发生率。结果:研究组治疗总有效率为97.44%,高于对照组的79.48%,差异有统计学意义(P<0.05);研究组CD4+、CD8+和CD4+/CD8+水平均低于对照组,差异有统计学意义(P<0.05);研究组IL-2、IL-4、IL-6水平均低于对照组,差异有统计学意义(P<0.05);研究组病原清除率为94.87%(37/39),明显高于对照组的74.35%(29/39),差异有统计学意义(P<0.05);研究组听力阈值低于对照组,差异有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:炎可宁联合氧氟沙星治疗急性化脓性中耳炎患儿可提高治疗总有效率和病原清除率,降低T细胞亚群指标水平、炎性因子水平和听力阈值,其效果优于单纯氧氟沙星治疗。  相似文献   
8.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals.  相似文献   
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目的:探讨长链非编码 RNA(lncRNA)RUNX1-IT1在结直肠癌中的表达及其对结直肠癌细胞侵袭和迁移的影响机制。方法:收集2017年1月—2019年1月于河北北方学院附属第一医院进行根治性手术切除的结直肠癌组织标本62例及其相应的癌旁正常组织标本,采用荧光定量PCR(qPCR)法检测结直肠癌组织和其相应的癌旁组织中lncRNA RUNX1-IT1的表达。并培养人结直肠癌细胞系(SW480、SW620、HCT-116)和人正常结直肠上皮细胞系(FHC),qPCR检测细胞系中 lncRNA RUNX1-IT1和 miR-21的表达水平,选择最适细胞系用于后续实验。通过上调或下调SW480细胞中lncRNA RUNX1-IT1和miR-21的表达后,采用qPCR检测lncRNA RUNX1-IT1和miR-21的表达水平,双荧光素酶报告基因实验验证lncRNA RUNX1-IT1和miR-21的靶向关系,Transwell实验检测SW480细胞侵袭和迁移能力。结果:qPCR检测结果显示,与癌旁正常组织比较,lncRNA RUNX1-IT1在结直肠癌组织中表达降低(P<0.05),而miR-21在结直肠癌组织中表达升高(P<0.05),且lncRNA RUNX1-IT1与miR-21在结直肠癌组织中的表达呈负相关(r=-0.275,P=0.031)。与正常结直肠 FHC细胞相比,lncRNA RUNX1-IT1在 3种结直肠癌细胞系中的表达水平均显著降低(均为P<0.05),而miR-21均显著升高(均为P<0.05),且SW480细胞最明显,故后续采用SW480细胞系进行实验。双荧光素酶报告基因实验证实lncRNA RUNX1-IT1靶向调节miR-21的表达;与对照组相比,过表达lncRNA RUNX1-IT1可抑制SW480细胞侵袭和迁移能力(P<0.05);抑制 miR-21表达可抑制 SW480细胞侵袭和迁移能力(P<0.05);上调 miR-21表达可逆转过表达 lncRNARUNX1-IT1对 SW480细胞侵袭和迁移的抑制作用(P<0.05)。结论:LncRNA RUNX1-IT1在结直肠癌中表达下调,lncRNARUNX1-IT1通过靶向miR-21调控SW480细胞侵袭和迁移。  相似文献   
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PurposeThe clinical manifestations of rickettsial diseases mimic other endemic infections with similar presentations thus posing a serious challenge to clinicians for their diagnosis. For the diagnosis of rickettsial disease serological tests like Weil Felix, ELISA and IFA are used. There are limited studies that have evaluated different serological tests for the diagnosis of rickettsial diseases. Therefore, the present study was undertaken to evaluate the ELISA and Weil Felix test for the diagnosis of rickettsial diseases prevalent in this region.MethodsSamples from 281 patients clinically suspected of rickettsial diseases were tested for spotted fever group (SFG), typhus group (TG) and scrub typhus group (STG) by Weil Felix, ELISA and IFA was taken as the gold standard. Baseline titers and cut-off ODs were calculated by taking samples from healthy blood donors.ResultsThe sensitivity, specificity, positive and negative predictive value of Weil Felix test ranged from 30% to 44%, 83.46%–97.86%, 9%–77%, 92–96% respectively. The sensitivity and specificity, positive and negative predictive value of ELISA ranged from 80.77% to 96.15%, 96.33%–98.43%, 70.21%–88.64%, 92.89%–99.60% respectively. Maximum cross-reactions were observed between SFG and STG by the Weil Felix test and between STG and TG by ELISA.ConclusionsELISA was found to be sensitive and specific for the diagnosis of rickettsial diseases. It is easy to perform, does not require a technical expert for result interpretation and a large number of samples can be processed at a time.  相似文献   
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