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81.
长期雾化吸入硝酸甘油对高肺血流大鼠肺动脉压力及肺血管结构重建的影响 总被引:4,自引:1,他引:4
目的探讨长期雾化吸入硝酸甘油对高肺血流大鼠肺动脉压力、肺血管结构的作用及其机制。方法24只健康雄性Wistar大鼠随机分为对照组、分流组和吸入组。对分流组和吸入组大鼠开腹行腹主动脉-下腔静脉分流术,12周后两组大鼠分别雾化吸入生理盐水和硝酸甘油3周。以右心导管法测定肺动脉压,颈动脉插管测定体循环压,检测右心室肥厚,观测肺血管显微及超微结构变化,用免疫组织化学法检测大鼠肺动脉人类尾加压素Ⅱ(hUⅡ)的表达。结果分流组大鼠肺动脉平均压(PAMP)和右心室/左心室 室间隔重量比值(RV/LV S)明显高于对照组(P<0.01),且分流组大鼠肺小血管肌化程度明显增强(P<0.01),中、小型肺肌型动脉相对厚度(RMT)增加,肺动脉内皮细胞和平滑肌细胞hUⅡ表达明显增强。吸入组大鼠mSBP未受影响,PAMP明显低于分流组(P<0.01),RV/(LV S)高于对照组(P<0.01),但与分流组比较差异无显著性(P>0.01),吸入组大鼠肺小血管肌化程度明显改善,小型肺肌型动脉RMT及小型肺动脉内皮细胞和平滑肌细胞hUⅡ减少。结论长期雾化吸入硝酸甘油可缓解高肺血流量所致肺动脉高压和肺血管结构的重建,其对肺动脉内皮细胞和平滑肌细胞hUⅡ表达的抑制作用,可能参与高肺血流量所致肺血管结构重建和肺动脉高压的调节。 相似文献
82.
BACKGROUND: This report examines recurrent pediatric groin hernias and the role of diagnostic laparoscopy in the management of these recurrences. METHODS: A chart review of 19 children presenting with recurrent hernias was performed, analyzing the type of primary hernia, nature of recurrence, preexisting medical conditions, surgical complications at primary repair, and time to recurrence. Diagnostic laparoscopy (DL) was used during the remedial repair of the last nine patients. RESULTS: Seventeen indirect hernias were repaired during the primary repair, and 1 femoral hernia was identified. In one child, no inguinal hernia was identified at the initial operation. Overall, 11 recurrences were found to consist of indirect sacs, and 4 were found to have attenuation of the inguinal floor. Four additional recurrences were found to be femoral hernias. In only 1 patient was a wound factor (infection) thought to play a role in the recurrence. Diagnostic laparoscopy in 9 patients found 4 (44%) to have unsuspected intraoperative findings. Four femoral hernias were identified (3 with unsuspected contralateral femoral hernias). Additionally, 1 unsuspected recurrence of an indirect sac was identified. CONCLUSIONS: Laparoscopy accurately identifies the nature of the defect in children with recurrent groin hernias, detecting unsuspected contralateral indirect, direct, or femoral hernias in 44% of those undergoing laparoscopy. 相似文献
83.
目的分析剖宫产率升高的原因,寻求解决问题的办法,严格掌握剖宫产的手术指征,使诊治更为科学,确保母婴健康。方法对1996年1月1日 ̄2005年10月31日在我院进行剖宫产手术分娩的1570例病例进行回顾性分析,总结分析剖宫产率上升的原因及因素变迁,并提出相应的对策。结果剖宫产率呈逐年上升趋势,尤其近5 ̄6年来,上升明显,究其原因,胎儿窘迫、头盆不称、孕妇精神因素及部分社会因素为主要因素。结论加强围产期宣教,认真做好孕产期监护,医患之间加强沟通,减少医患纠纷,严格掌握剖宫产指征,以最大限度地降低剖宫产率和母婴死亡率。 相似文献
84.
Objective: To investigate the distribution of TRPA1 (one kind of the TRP-like ion channel family) channel in the hippocampus and cerebral cortex of rat. Methods: RT-PCR was used to amplify the fragment of TRPA1 in the DRG (dorsal root ganglion), hippocampus and cerebral cortex of adult SD rat. In situ hybridization staining was used to show the distribution of TRPA1 mRNA in the hippocampus and cerebral cortex of adult rat brain. Results: Both RT-PCR and in situ hybridization staining showed that TRPA1 mRNA was expressed in hippocampus and cerebral cortex of the adult rat brain. Conclusion: Our results suggest that there is expression of TRPA1 mRNA both in the hippocampus and cerebral cortex of the adult rat brain. 相似文献
85.
86.
目的 建立临床急诊急救中药物中毒发生率最高的 2 3种药物在血液、胃液或呕吐物样品中的毛细管气相色谱分析法。方法 血液、胃液或呕吐物样品经处理后 ,以溴己新为内标 ,采用SP 5 0 2型气相色谱仪、SE 5 4型毛细管色谱柱、氢焰检测器检测巴比妥、对乙酰氨基酚、异戊巴比妥、苯海拉明、苯巴比妥、氯苯那敏 (扑尔敏 )、普萘洛尔 (心得安 )、阿米替林、多赛平 (多虑平 )、安坦、异丙嗪、苯妥英钠、罗拉、安定、氯丙嗪、甲氧氯普胺 (胃复安 )、三氟拉嗪、硝西泮 (硝基安定 )、思诺思、氯氮平、艾司唑仑、氟哌啶醇、阿普唑仑等 2 3种药物。结果 该方法在选定条件下 ,能将样品中 2 3种药物成分分离 ,线性范围为 0 .0 2~ 30 .0 0mg L ,最低检出浓度为 0 .0 2~ 0 .5 0mg L ,平均回收率为 86 .8%~10 2 .8% ,相对标准偏差为 2 .8%~ 6 .2 %。结论 该方法操作简便 ,灵敏度高 ,可快速、准确地为临床提供诊断依据。 相似文献
87.
目的:分析与总结苏州大学附属儿童医院临床试验机构质控中发现的问题。 方法:按照国家药品监督管理局食品药品 审核查验中心最新发布的核查要点对 2021 年 1 月-2023 年 6 月机构质控报告中的问题进行整理与归类。 结果:本机构临床试 验项目质控中发现的问题主要集中在研究人员资质文件收集、知情同意书签署、异常值评判、试验数据记录等方面。 结论:临床 试验机构、伦理委员会、研究者和申办方均应履行各自职责,对试验质量全程把关,保障受试者的权益与安全、保证临床试验数 据的真实性。 相似文献
88.
ObjectiveThe postoperative role of adjuvant radiotherapy in non-metastatic head and neck adenoid cystic carcinoma (ACC) remains controversial. We analyzed adjuvant radiotherapy’s effect on surgical patient survival.MethodsPatients diagnosed with ACC from 2004 to 2015 in the Surveillance, Epidemiology, and End Results database were analyzed. The overall survival (OS) and disease-specific survival (DSS) of patients after adjuvant radiotherapy were assessed using the Kaplan–Meier and multivariate Cox methods. Propensity score matching (PSM) was performed to adjust confounders between patients with or without adjuvant radiotherapy; a forest plot was generated by subgroup analysis.ResultsThe study included 742 patients. In the PSM cohort, adjuvant radiotherapy did not improve OS or DSS. Radiotherapy was not a protective factor for OS or DSS in the univariate and multivariate Cox proportional hazard models. In the subgroup analysis, postoperative radiotherapy improved the OS of female and N1-stage patients and those with oropharyngeal tumors or over 79 years and the DSS of N1-stage patients.ConclusionsPostoperative radiotherapy showed different benefits in ACC patients, and postoperative radiotherapy recommendations should be individualized. Female and N1-stage ACC patients and those with oropharyngeal tumors or patients over 79 years without distant metastases postoperatively could benefit from adjuvant radiotherapy. 相似文献
89.
The rGO/CeO2/FTO nanocomposite modified electrode was prepared by an electrochemical method. A simple and highly sensitive electrochemical sensing platform for electrochemical rGO and modified CeO2 nanoribbons directly on FTO electrodes was developed. Simultaneous determination of Pb2+ and Cd2+ used the differential pulse anodic stripping voltammetry (DPASV) method. The method was simple to operate, and CeO2 nanobelts could be obtained simultaneously by electrodeposition and reduction of GO without further processing. This is an environmentally friendly electrochemical method to obtain modified electrodes under mild conditions. The experimental results showed that the linear calibration curves of Pb2+ and Cd2+ are 1–300 and 0.2–500 μg L−1, respectively. At the same time, no interference from other coexisting metal ions was found during the detection process, which proved that the modified electrode had good stability and repeatability.The rGO/CeO2/FTO nanocomposite modified electrode was prepared by an electrochemical method. 相似文献
90.
Di Cui Lei Du Wei Yu Boning Cai Lingling Meng Jun Yang Yanrong Luo Jing Chen Dr. Lin Ma 《Radiology and oncology》2022,56(2):216
BackgroundOur previous study showed that two different regimens of moderate hypofractionated radiotherapy (HFRT) delivered with helical tomotherapy (HT) are well tolerated in older prostate cancer patients. We provide a longterm efficacy and toxicity after > 7 years of follow-up.Patients and methodsThe study recruited 33 patients from February 2009 to July 2011 (76 Gy/34F; Group-1); and 34 from July 2011 to February 2014 (71.6 Gy/28F; 50.4 Gy/25F for the risk of pelvic lymph nodes involvement (LNI) >15%; Group-2). The primary outcomes were biochemical failure (BF), biochemical failure and clinical disease failure (BCDF), progression-free survival (PFS), overall survival (OS), late genitourinary (GU) and gastrointestinal (GI) toxicity.ResultsThe average ages of two groups were 80 and 77 years and the proportions of patients with LNI > 15% were 69.7% and 73.5%, respectively. At the final follow-up in February 2020, 27.3% and 20.6% cases experienced BF, with a median time until BF of 3.3 years. A total of 38.8% patients reached primary endpoints, in which 18 deaths were reported BCDF events (45.5% vs. 32.4%, p = 0.271). There was no significant difference in 7-year PFS (68.6% vs. 74.8%, p = 0.591), BCDF (45.5% vs. 32.4%, p = 0.271) and OS (71.9% vs. 87.5%, p = 0.376) for full set analysis and for subgroup analysis (all p > 0.05). The incidence of grade ≥ 2 late GU (6.2% vs. 6.3%, p = 0.127) and GI toxicities (9.4% vs. 15.6%, p = 0.554) was comparable.ConclusionsIn older patients with localized prostate cancer, two moderate hypofractionated regimens were all well tolerated with similar, mild late toxicities and satisfactory survival, without necessity of prophylactic pelvic node irradiation.Key words: helical tomotherapy, radiation dose hypofractionation, progression-free survival, follow-up studies, prostatic neoplasms, adenocarcinoma 相似文献