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111.
符文琛 《工业卫生与职业病》1987,(1)
通过对冶金、锻造、铸造、陶瓷、纺织、印染、铁路、航运等行业的16个作业环境热环境参数和工人生理反应关系的调查,对现行的高温作业分级标准不足之处提出了一些看法,并认为IS0提出的热环境下机体反应的阈限值对我国亦是适宜的。经统计学分析发现,作业环境的计算温度和工人平均体温之间有明显相关(r=0.86)。不同气温下464名工人的主观感觉调查表明,35℃时100%的工人都有热或很热的感觉。 相似文献
112.
113.
预期无残疾寿命(ELWD)在国外公共卫生及老年医学研究中已得到普遍重视,但ELWD的计算中却存在着若干错误,直接影响着ELWD的正确使用。文章简述了ELWD的概念及原理,推导了正确的计算公式,并以实例说明了计算步骤及方法,对ELWD在医学研究中的应用进行了讨论。 相似文献
114.
Development of a Novel Scale to Assess Life Fulfilment as Part of the Further Refinement of a Quality-of-Life Model for Epilepsy 总被引:2,自引:1,他引:1
Summary: We have been involved in developing a health-related quality-of-life model for use as an outcome measure in epilepsy. As part of the further development of this model, we have developed a measure of life fulfilment. This scale is based on methods previously described by Krupinski in 1980. The value of Krupinski's approach is the opportunity for patients to weight the numerous aspects of their quality of life and assess the discrepancy between their actual and desired circumstances. The life fulfilment scale has been shown to be reliable (α= 0.7) and valid. The scale is currently being applied to several clinical studies in epilepsy. We believe that the scale provides a valuable contribution to our health-related quality-of-life model. 相似文献
115.
MIC distribution data were obtained from a variety of international sources, and pooled after selection by a defined criterion. Sixty-seven of these datasets were subjected to a range of statistical goodness-of-fit tests. The log-normal distribution was selected for subsequent modelling. Cumulative counts of MIC distribution data were fitted to the cumulative log-normal distribution using non-linear least squares regression for a range of data subsets from each antibiotic-bacterium combination. Estimated parameters in the regression were the number of isolates in the subset, and (the log(2) values of) the mean and standard deviation. Optimum fits for the cumulative log-normal curve were then used to determine the wild-type MIC range, determined by calculating the MICs associated with the lower and upper 0.1% of the distribution, rounding to the nearest two-fold dilution, and calculating the probabilities of values higher and lower than these values. When plotted logarithmically, histograms of MIC frequencies appeared normal (Gaussian), but standard goodness-of-fit tests showed that the two-fold dilution grouping of MICs fits poorly to a log-normal distribution, whereas non-linear regression gave good fits to population (histogram) log-normal distributions of log(2) MIC frequencies, and even better fits to log-normal cumulative distributions. Optimum fits were found when the difference between the estimated and true number of isolates in the fitted subset was minimal. Sixteen antibiotic-bacterium datasets were fitted using this technique, and the log(2) values of the means and standard deviations were used to determine the 0.1% and 99.9% wild-type cut-off values. When rounded to the nearest two-fold dilution, > or = 98.5% of MIC values fall within the cut-off value range. Non-linear regression fitting to a cumulative log-normal distribution is a novel and effective method for modelling MIC distributions and quantifying wild-type MIC ranges. 相似文献
116.
117.
慢性乙型肝炎患者抗病毒治疗后生存质量评估 总被引:13,自引:0,他引:13
目的了解慢性乙型肝炎(CHB)患者生存质量(QOL)状况,并通过抗病毒治疗对其QOL进行干预.方法采用横断面调查,选择2003年至2004年期间武汉大学人民医院感染科212例慢性乙型肝炎患者及健康人群185例,分别以健康状况问卷(SF-36)、医学应对问卷以及肝病特质问卷进行调查.结果与健康对照组比较,CHB患者除情感职能(RE)外,其他维度得分均明显低于健康对照者(P<0.05).CHB患者QOL与年龄、肝病特质问卷得分以及医学应对问卷中的屈服、面对因子分显著负相关(P<0.01).虽然不同抗病毒治疗方案对CHB患者QOL的影响差异无统计学意义,但完全应答组与无应答组比较,两组除社会功能(SF)(P<0.05)以外其他维度的得分差异均有统计学意义(P<0.01);部分应答组与无应答组比较,仅RE、躯体疼痛(BP)及一般健康状况(GH)维度的得分差异有统计学意义(P<0.05).结论CHB患者QOL多个纬度均有受损.有效的抗病毒治疗能提高患者的QOL. 相似文献
118.
D.R. Pina S.B. Duarte J. Morceli T. Ghilardi Netto 《Applied radiation and isotopes》2006,64(12):1623-1630
We present the construction of a homogeneous phantom to be used in simulating the scattering and absorption of X-rays by a standard patient chest and skull when irradiated laterally. This phantom consisted of lucite and aluminium plates with their thickness determined by a tomographic exploratory method applied to the anthropomorphic phantom. Using this phantom, an optimized radiographic technique was established for chest and skull of standard sized patient in lateral view. Images generated with this optimized technique demonstrated improved image quality and reduced radiation doses. 相似文献
119.
Arne Skretting Elin Strandmyr Mette W. Lindegaard 《European journal of nuclear medicine and molecular imaging》1990,17(1-2):10-14
A prototype version of a recently developed transmission phantom for simulation of radionuclide bone studies was used in a Norwegian nationwide quality assurance project. The design of the phantom made it possible to perform a receiver operation characteristic (ROC) examination with respect to the detection of radionuclide accumulation in the ribs. The participants were also asked to report accumulation in the spinal column. Images obtained by means of a uniform source and a four-quadrant bar pattern were used to judge resolution and homogeneity with the collimator used in the bone studies. The overall performance of the laboratories was satisfactory, but considerable variations were found. There was a marked correlation between the physician's performance and the resolution and homogeneity of the camera. Reports from stationary imaging were generally better than those that were based on whole-body scans. 相似文献
120.
S. Irani C. Mahler L. Goetzmann E.W. Russi A. Boehler 《American journal of transplantation》2006,6(2):404-411
Since lung transplant recipients are susceptible to infections and inhaled pollution, many centers warn against pets. However, data supporting this recommendation are lacking. Our program is less restrictive regarding pets. This study, for the first time, investigates the association of pets with physiological and psychological parameters in these patients. A questionnaire concerning pets was sent to 104 lung transplant recipients. Lung function tests, levels of exhaled nitric oxide (FE(NO)), need for antibiotic treatments and hospitalizations, creatinine clearance, body mass index (BMI) and demographic data were assessed. Additionally, the questionnaire of life satisfaction (FLZ), a question on summarized life satisfaction (LS), the life orientation test (LOT), the hospital anxiety depression scale (HADS) and the social support questionnaire (F-SozU) were assessed. Response rate was 86%. Fifty-two percent defined themselves as pet owners, whereas 48% did not. The two groups did not differ in demographic or physiological data. Significant differences in FLZ (79/65, p = 0.04), in LS (4.3/3.9, p = 0.01), LOT (32/29, p = 0.006) and F-SozU (4.5/4.2, p = 0.04) were found in favor of pet owners. In lung transplant recipients keeping pets the frequency of somatic complications is not higher compared to lung transplant recipients without pets. After lung transplantation, pets are associated with a better quality of life. 相似文献