全文获取类型
收费全文 | 4773篇 |
免费 | 285篇 |
国内免费 | 66篇 |
专业分类
耳鼻咽喉 | 64篇 |
儿科学 | 75篇 |
妇产科学 | 27篇 |
基础医学 | 304篇 |
口腔科学 | 128篇 |
临床医学 | 555篇 |
内科学 | 543篇 |
皮肤病学 | 41篇 |
神经病学 | 56篇 |
特种医学 | 209篇 |
外科学 | 272篇 |
综合类 | 460篇 |
一般理论 | 1篇 |
预防医学 | 1881篇 |
眼科学 | 72篇 |
药学 | 282篇 |
1篇 | |
中国医学 | 65篇 |
肿瘤学 | 88篇 |
出版年
2024年 | 6篇 |
2023年 | 55篇 |
2022年 | 123篇 |
2021年 | 191篇 |
2020年 | 151篇 |
2019年 | 140篇 |
2018年 | 133篇 |
2017年 | 165篇 |
2016年 | 126篇 |
2015年 | 160篇 |
2014年 | 223篇 |
2013年 | 407篇 |
2012年 | 265篇 |
2011年 | 334篇 |
2010年 | 227篇 |
2009年 | 198篇 |
2008年 | 245篇 |
2007年 | 257篇 |
2006年 | 237篇 |
2005年 | 163篇 |
2004年 | 157篇 |
2003年 | 150篇 |
2002年 | 115篇 |
2001年 | 99篇 |
2000年 | 94篇 |
1999年 | 74篇 |
1998年 | 68篇 |
1997年 | 64篇 |
1996年 | 67篇 |
1995年 | 50篇 |
1994年 | 64篇 |
1993年 | 38篇 |
1992年 | 51篇 |
1991年 | 39篇 |
1990年 | 44篇 |
1989年 | 21篇 |
1988年 | 24篇 |
1987年 | 11篇 |
1986年 | 15篇 |
1985年 | 15篇 |
1984年 | 12篇 |
1983年 | 2篇 |
1982年 | 12篇 |
1981年 | 7篇 |
1980年 | 3篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1977年 | 2篇 |
1975年 | 3篇 |
1972年 | 1篇 |
排序方式: 共有5124条查询结果,搜索用时 15 毫秒
141.
C. Tissier C. Bonithon-Kopp M. Freysz 《Annales fran?aises d'anesthèsie et de rèanimation》2013,32(7-8):465-471
IntroductionThe blunt trauma victim management is still a matter of debate and comparing studies involving different emergency medical services and health care organization remains fictitious. Hence, the French Intensive care Recorded in Severe Trauma (FIRST) was conducted in order to describe the severe blunt trauma management in France. The present paper aimed at recalling the main results of FIRST study.MethodsThe FIRST study was based on a multicenter prospective cohort of patients aged 18 or over with severe exclusive blunt trauma requiring admission to university hospital care unit within the first 72 h and/or managed by medical-Staffed Emergency Mobile Unit (SMUR). Multiple data were collected about patient characteristics, clinical initial status, typology of trauma and the main endpoints were 30-day mortality.ResultsSixty-one percent of trauma patients were road traffic victims and 30% were domestic, sport or leisure trauma. Patients who benefited from medical pre-hospital management were globally more severely injured than those who received basic life support care by fire brigades. Therefore, they were delivered more aggressive treatment in the pre-hospital setting and the median time for their hospital admission was lengthened. However, their 30-day mortality was significantly reduced. The probability of death was also decreased when casualties were transported by SMUR helicopter directly to the university hospital. In the in-hospital setting, the performance of a whole-body computed tomography (CT) was associated with a significant reduction in the mortality risk compared with a selective CT.ConclusionThe FIRST study suggests the benefit of a medical management in the pre-hospital setting on the survival of trauma patients. The emergency physician (EP) expertise in the pre-hospital and initial hospital phases would lead to the concept of the appropriate care for the appropriate trauma patient. It also highlights the necessity to set up organized regional sectors of care and registries. 相似文献
142.
目的提高细支气管肺泡癌(BAC)的X线、CT诊断水平.材料与方法回顾性分析24例BAC的X线、CT表现,将其分为结节型、炎症型和弥漫型.结果结节型7例,均为单发结节.炎症型6例,两肺多发斑片状影4例,大叶实变2例.弥漫型11例,两肺呈细小结节影10例,网状结节影1例.单侧或双侧胸腔少量积液8例,心包大量积液5例,双侧肺门淋巴结增大3例.胸部及远处骨质破坏6例.结论BAC影像表现多种多样,炎症型需与肺结核、肺炎等鉴别.仔细观察、分析X线、CT征象并结合临床表现与治疗情况,可提高BAC的诊断正确率. 相似文献
143.
目的探讨甘氨酸龈下喷砂联合引导组织再生术(GTR)治疗种植体周围炎的有效性。
方法28例伴有牙槽骨吸收的种植体周围炎患者,按照随机、双盲、对照原则将种植体(共34枚)分成2组,分别行GTR,其中试验组(n= 18)在术中使用甘氨酸龈下喷砂系统对种植体表面进行清创;对照组(n= 16)采用塑料刮治器对种植体表面进行清创。在治疗前(基线)、治疗后3个月、治疗后6个月和治疗后12个月进行临床指标的检测,包括菌斑指数(PLI)、出血指数(BI)、探诊深度(PD)、临床附着水平(CAL)及影像学垂直骨增量。数据采用重复测量资料的方差分析,每个时间点采用独立样本t检验进行分析,试验组和对照组分别进行治疗前与治疗后的自身对比,并在基线、治疗后3个月、治疗后6个月和治疗后12个月进行临床指标的组间对比,以P<0.05为差异有统计学意义。
结果在基线,试验组和对照组各临床指标差异无统计学意义(P>0.05)。各组术后PLI、BI、PD、CAL及影像学垂直骨增量均较治疗前(基线)有明显改善,差异有统计学意义(P<0.05)。患者治疗后3个月,试验组与对照组BI、PLI、PD、CAL差异均有统计学意义(tBI= 5.103,PBI= 0.031;tPLI= 5.556,PPLI= 0.025;tPD= 4.440,PPD= 0.043;tCAL= 4.879,PCAL= 0.034)。患者治疗后6个月,试验组和对照组的PD、CAL差异均有统计学意义(tPD= 4.994,PPD= 0.033;tCAL= 4.831,PCAL= 0.035)。患者治疗后12个月,试验组和对照组的PD、CAL差异均有统计学意义(tPD= 4.302,PPD= 0.046;tCAL= 4.325,PCAL= 0.048)。患者治疗后6及12个月,试验组与对照组种植体的PLI和BI均有改善,但差异无统计学意义(P>0.05)。患者影像学垂直骨增量在治疗后3、6、12个月试验组较对照组增加更明显,差异均有统计学意义(t3=4.831,P3= 0.035;t6= 4.412,P6= 0.044;t12= 5.087,P12= 0.031)。
结论在改善种植体周围炎炎症水平及促进牙槽骨再生方面,甘氨酸龈下喷砂联合GTR较机械刮治联合GTR更具优势,可考虑在GTR中使用甘氨酸龈下喷砂来提高种植体周围炎的治疗效果。 相似文献
144.
145.
目的调查对比驻高原与驻平原空军官兵口腔健康状况,为驻高原空军官兵口腔疾病防治提供参考依据。方法对驻高原(平均海拔3900m)空军某部官兵990人(高原组)和驻平原(平均海拔500m)空军某部官兵910人(平原组)进行口腔健康调查。调查内容包括龋病、牙结石、牙龈炎和牙周炎发病情况。结果高原组官兵较平原组官兵口腔疾病发生率高,且驻高原时间越长,口腔患病率越高;高原组患龋病率、牙结石检出率、牙龈炎和牙周炎患病率均高于平原组(Ρ<0.05)。结论驻高原空军官兵口腔疾病患病率较平原官兵高,加强对高原官兵口腔卫生宣传教育,改善高原医疗卫生条件和环境对降低高原官兵口腔疾病发生,提高部队战斗力具有重要意义。 相似文献
146.
目的 探讨充气升温仪在全身麻醉苏醒期中的应用价值。方法 分析空军总医院2016-05至2017-02间行腹腔镜胆囊切除手术治疗的130例苏醒期使用充气升温仪复温的情况,随机分为2组,其中试验组58例,对照组72例。试验组应用充气升温仪升温,对照组为常规复苏。记录比较两组患者的手术时间、出血量、输液量、尿量、拔管时间、完全清醒时间、躁动及寒战发生率。结果 130例均完成腹腔镜胆囊切除手术,两组间手术时间、输液量、出血量、尿量比较,差异均无统计学意义;试验组的拔管时间、完全清醒时间均短于对照组[(13.8±7.2) min vs (19.6±7.8) min;(47.5±7.6) min vs (55.6±11.5) min],差异有统计学意义(P<0.01)。试验组患者躁动及寒战发生率均显著低于对照组(10.3% vs 25.0%; 6.9% vs 30.6%),差异有统计学意义。结论 充气升温仪能缩短拔管及全麻苏醒时间,降低躁动及寒战发生率,值得临床推广。 相似文献
147.
Ryan Kohlbrenner K. Pallav Kolli Andrew G. Taylor Maureen P. Kohi Evan D. Lehrman Nicholas Fidelman Miles Conrad Jeanne M. LaBerge Robert K. Kerlan Robert Gould 《Journal of vascular and interventional radiology : JVIR》2017,28(8):1129-1135.e1
Purpose
To assess radiation dose reduction during uterine fibroid embolization (UFE) using an optimized angiographic processing and acquisition platform.Materials and Methods
Radiation dose data for 70 women (mean age, 46 y; range, 34–67 y) who underwent UFE were retrospectively analyzed. Twenty-one patients underwent UFE using the baseline fluoroscopic and angiographic image acquisition platform, and 49 underwent UFE after implementing an optimized imaging platform in otherwise identical angiography suites. Cumulative kerma-area product (CKAP), cumulative air kerma (CAK), total fluoroscopy time, and image exposure number were collected for each procedure. Image quality was assessed by 3 interventional radiologists blinded to the platform used for image acquisition and processing.Results
Patients undergoing UFE using the new x-ray fluoroscopy platform had significantly lower CKAP and CAK indicators than patients for whom baseline settings were used. Mean CKAP decreased by 60% from 438.5 Gy · cm2 (range, 180.3–1,081.1 Gy · cm2) to 175.2 Gy · cm2 (range, 47.1–757.0 Gy · cm2; P < .0001). Mean CAK decreased by 45% from 2,034.2 mGy (range, 699.3–5,056.0 mGy) to 1,109.8 mGy (range, 256.6–4,513.6 mGy; P = .001). No degradation of image quality was identified through qualitative evaluation.Conclusions
Significant reduction in patient radiation dose indicators can be achieved with use of an optimized image acquisition and processing platform. 相似文献148.
目的:研究潜艇舱室空气中有害气体的组成及主要成分的浓度,为研究潜艇空气控制系统和修订“潜艇舱室空气组分容许浓度”提供依据。方法:在潜艇取样,用气相色谱-质谱仪(GC-MS)作为定性分析的主要手段。用GC及多种专用分析方法在现场作定量分析。结果:定性鉴别出潜艇舱室空气中376种组分,包括脂肪烃、芳香烃、卤代烃、含氧有机物、无机成分等几类;定量测定了舱室中71种组分的浓度;以定量测定结果为主要依据,结合各组分的毒性大小、来源广泛性等因素,提出了舱室中应重点监控的组分及其顺序。结论:潜艇舱室空气污染组成很复杂,某些组分(CO2、CO、HCl、H2SO4、O3等)的浓度有时超过容许标准,需加强监测和控制 相似文献
149.
目的寻找留置针接肝素帽时封管排除帽内残留空气的有效方法。方法将150例术后留置有静脉留置针未连接肝素帽的输液患者随机分成实验组(A组)和对照组(B组、C组),A组采用改良封管法,B组先回抽后封管,C组直接封管,比较三组病例封管后帽内空气残留、针管回血、患者对护士封管的满意度、紧张情绪产生状况。结果采用A组方法患者在无空气残留、无回血率、无紧张情绪产生、对护士封管的满意度方面明显优于对照(B、C)组(P〈0.05)。结论实验组方法能有效避免肝素帽内空气残留及静脉回血,减少患者的紧张情绪,提高患者对护士工作的满意度。 相似文献
150.
Inhalation exposure to ambient polycyclic aromatic hydrocarbons and lung cancer risk of Chinese population 下载免费PDF全文
Yanxu Zhang Shu Tao Huizhong Shen Jianmin Ma 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(50):21063-21067
An Euler atmospheric transport model (Canadian Model for Environmental Transport of Organochlorine Pesticides, CanMETOP) was applied and validated to estimate polycyclic aromatic hydrocarbon (PAH) ambient air concentrations at ground level in China based on a high-resolution emission inventory. The results were used to evaluate lung cancer risk for the Chinese population caused by inhalation exposure to PAHs. The uncertainties of the transport model, exposure, and risk analysis were assessed by using Monte Carlo simulation, taking into consideration the variation in PAH emission, aerosol and OH radical concentrations, dry deposition, respiration rate, and genetic susceptibility. The average benzo[a]pyrene equivalent concentration (B[a]Peq) was 2.43 [≈1.29–4.50 as interquartile range (IR)] ng/m3. The population-weighted B[a]Peq was 7.64 (IR, ≈4.05–14.1) ng/m3 because of the spatial overlap of the emissions and population density. It was estimated that 5.8% (IR, ≈2.0–11%) of China''s land area, where 30% (IR, ≈17–43%) of the population lives, exceeded the national ambient B[a]Peq standard of 10 ng/m3. Taking into consideration the variation in exposure concentration, respiration rate, and susceptibility, the overall population attributable fraction (PAF) for lung cancer caused by inhalation exposure to PAHs was 1.6% (IR, ≈0.91–2.6%), corresponding to an excess annual lung cancer incidence rate of 0.65 × 10−5. Although the spatial variability was high, the lung cancer risk in eastern China was higher than in western China, and populations in major cities had a higher risk of lung cancer than rural areas. An extremely high PAF of >44% was estimated in isolated locations near small-scale coke oven operations. 相似文献