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81.
Nicole E. Sharp Wendy J. Svetanoff Amita Desai Hanna Alemayehu Maneesha U. Raghavan Susan W. Sharp James C. Brown Douglas C. Rivard Shawn D. St. Peter George W. Holcomb III 《The Journal of surgical research》2014
Background
We have previously reported that children receive significantly less radiation exposure after abdominal and/or pelvis computed tomography (CT) scanning for acute appendicitis when performed at our children's hospital (CH) rather than at outside hospitals (OH). In this study, we compare the amount of radiation children receive from head CTs for trauma done at OH versus those at our CH.Methods
A retrospective chart review was performed on all children transferred to our hospital after receiving a head CT for trauma at an OH between July 2012 and December 2012. These children were then blindly case matched based on date, age, and gender to children at our CH.Results
There were 50 children who underwent head CT scans for trauma at 28 OH. There were 21 females and 29 males in each group. Average age was 7.01 ± 0.5 y at the OH and 7.14 ± 6.07 at our CH (P = 0.92). Average weight was 30.81 ± 4.69 kg at the OH and 32.69 ± 27.21 kg at our CH (P = 0.81). Radiation measures included dose length product (671.21 ± 22.6 mGycm at OH versus 786.28 ± 246.3 mGycm at CH, P = 0.11) and CT dose index (53.4 ± 2.26 mGy at OH versus 49.2 ± 12.94 mGy at CH, P = 0.56).Conclusions
There is no significant difference between radiation exposure secondary to head CTs for traumatic injuries performed at OH and those at a dedicated CH. 相似文献82.
目的:了解一起食源性疾病暴发的原因.方法:采用流行病学调查及实验室分离培养确认致病原.结果:在3份病人肛试子和3份末梢水中检出有致病性大肠埃希氏菌,未检出其它致病菌.一日三餐均饮用该水的教师和家属发病率为66.67%,而在校一日只进一餐的学生发病率为26.23%,前者显著高于后者(χ2=52.63,P<0.01).当地场镇居民只用不饮此水未见发病.结论:通过流行病学调查和实验室病原学检查,证实本起疫情系一起致病性大肠埃希氏菌引起的食源性疾病暴发疫情. 相似文献
83.
In the experimental study on the electrophysiology and functions of heart in the animal,the thorax should be opened to expose the heart, at the same time natural breathing is maintained instead of artificial breathing. The key procedure of this new method is to avoid injuring the pleural cavity, so pneumothorax can be prevented. By means of this new method some subject studies have been finished. 相似文献
84.
目的 比较肌松监测下静脉注射罗库溴铵0.9mg/kg后60秒和4个成串刺激(train-of-four,TOF)的T1达到最大抑制程度时的气管插管条件,探讨该药理想的气管插管时机.方法 120例行择期腹腔镜胆囊切除术患者,年龄18岁~60岁,ASA Ⅰ-Ⅱ级,随机均分为两组.分别于静脉注射罗库溴铵0.9 mg/kg后60秒(A组)或T1达到最大抑制程度时(B组)行气管插管.观察并记录两组罗库溴铵起效时间(TOF的T1达到最大抑制程度的时间)、气管插管条件(Cooper's评分)、声门暴露程度(Cormack-Lehane分级)、诱导过程中的心率(heart rate,HR)和收缩压(systolic blood pressuref,SBP)变化以及术后24 h咽喉并发症(喉痛、声嘶等不适).结果 静注罗库溴铵0.9 mg/kg后66.0秒±18.1秒(95%可信区间30.2秒一101.8秒)达到T1最大抑制.B组Cooper's评分和Cormack-Lehane分级均优于A组(P相似文献
85.
86.
87.
《International journal of radiation biology》2013,89(5):390-399
Purpose:?To investigate time exposure dependence of continuous millimeter wave (CW) 99?GHz radiation on Escherichia coli bacterial cell viability and metabolic activity.Materials and methods:?Suspensions of E. coli bacterial cells with an optical density of OD660nm?=?0.1 were used for viability tests and OD660nm?=?1.0 for metabolic activity tests. These suspensions were exposed to 99?GHz CW electromagnetic radiation, generated by a Backward Wave Oscillator (BWO) tube base instrument with a horn antenna at the BWO exit, to obtain an almost ideal Gaussian beam. Calculations of the Gaussian beam show that a power of 0.2?mW/cm2 was obtained at the bacterial plane.Results:?The experimental results show that 1 hour of exposure to 99?GHz CW electromagnetic radiation had no effect on E. coli viability and colony characterisation. In 19?h of radiation, the number of colonies forming units was half order of magnitude higher than the sham-exposed and the control. However, 19?h of exposure did not affect the E. coli metabolic activity.Conclusions:?Exposure of E. coli to millimeter wave (MW) CW 99?GHz radiation for a short period did not affect the viability of E. coli bacterial cells. However, exposure for 19?h caused a slight proliferation but did not influence the metabolic activities of about 90 biochemical reactions that were examined. Hence, we assume that the slight proliferation (half order of magnitude) after 19?h of exposure dose not have a biological meaning. 相似文献
88.
AbstractBackground: The majority of day laborers in the USA are Latinos. They are engaged in high-risk occupations and suffer high occupational injury rates.Objectives: To describe on-the-job injuries reported by Latino day laborers, explore the extent that demographic and occupational factors predict injuries, and whether summative measures for total job types, job conditions, and personal protective equipment (PPE) predict injuries.Methods: A community survey was conducted with 327 participants at 15 corners in Houston, Texas. Hierarchical and multiple logistic regressions explored predictors of occupational injury odds in the last year.Results: Thirty-four percent of respondents reported an occupational injury in the previous year. Education, exposure to loud noises, cold temperatures, vibrating machinery, use of hard hats, total number of job conditions, and total PPE significantly predicted injury odds.Conclusion: Risk for injury among day laborers is not only the product of a specific hazard, but also the result of their exposure to multiple occupational hazards. 相似文献
89.
《International journal of occupational and environmental health》2013,19(1):26-32
AbstractObjectives: To describe the epidemiological and clinical characteristics of an outbreak of occupational silicosis and the associated working conditions.Methods: Cases were defined as men working in the stone cutting, shaping, and finishing industry in the province of Cádiz, diagnosed with silicosis between July 2009 and May 2012, and were identified and diagnosed by the department of pulmonology of the University Hospital of Puerto Real (Cádiz). A census of workplaces using quartz conglomerates was carried out to determine total numbers of potentially exposed workers. A patient telephone survey on occupational exposures and a review of medical records for all participants were conducted.Results: Silicosis was diagnosed in 46 men with a median age of 33 years and a median of 11 years working in the manufacturing of countertops. Of these cases, 91·3% were diagnosed with simple chronic silicosis, with an abnormal high-resolution computerized tomography (HRCT) scan. One patient died during the study period. Employer non-compliance in prevention and control measures was frequently reported, as were environmental and individual protection failures.Conclusions: The use of new construction materials such as quartz conglomerates has increased silicosis incidence due to intensive occupational exposures, in the context of high demand fuelled by the housing boom. This widespread exposure poses a risk if appropriate preventive measures are not undertaken. 相似文献
90.
《International journal of occupational and environmental health》2013,19(2):110-115
AbstractPolychlorinated biphenyls (PCBs) are a group of persistent organic pollutants with the ability to cause adverse impacts on human health and the environment. This study describes the indiscriminate use of PCB-contaminated transformer oil as a coolant in informal welding shops in Kalutara, Sri Lanka. Sixty-three welders, one each from a convenience sample of 63 welding workshops participated in the study. We administered a questionnaire and observed work practices. Sixty-two (98%) workplaces used transformer oil as the coolant in the welding equipment, 60 (95%) claiming that it was the only one available. Sixty-two (98%) did not use any protective measures when refilling coolant oil, while none of them safely disposed of the empty coolant oil containers. Only four (6%) were aware of the possible health effects of PCB-contaminated coolant oil. Health and safety measures in the work places studied were very poor. Coolant oil samples from a sub-sample of 30 welding workshops were tested for PCBs; 19 (63%) were positive. PCB-contaminated coolant oil is widely used by the welders in Kalutara without adequate precautions or safety measures. 相似文献