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991.
Sex-correlated differences in pain perception and behavior have been reported in several studies. Where such differences are found, they are most often in the direction of girls and women reporting more pain than is reported by boys and men. Although biologic, psychologic, and sociocultural factors act interdependently to influence pain responding, most efforts to explain sex-correlated differences in pain have focused on first-order biologic differences between the sexes. The current paper discusses empirical and theoretical literature addressing gender role socialization, cognitive factors, and affective factors associated with sex-correlated differences in pain. We affirm that there is convincing evidence that such psychosocial factors must be taken into account in research on sex-correlated differences in pain. We contend that the use of the dichotomous variable sex as a proxy for presumed biologic aspects of being female or male may obscure the contribution to sex-correlated differences that could be ascribed to the ways in which women and men are socialized with respect to pain perception and pain reporting. 相似文献
992.
The delivery of an intensity modulated radiation field with a dynamic multileaf collimator (MLC) requires precise correlation between MLC positions and cumulative monitor units (MUs). The purpose of this study is to investigate the precision of this correlation as a function of delivered MUs and dose rate. A semi-Gaussian shaped intensity profile and a simple geometric intensity pattern consisting of four square segments were designed to deliver a total of 1, 4, 16, 64, and 100 MUs at three different dose rates of 100, 400, and 600 MU/min. The semi-Gaussian intensity pattern was delivered using both sliding window and step and shoot techniques. The dose profiles of this intensity pattern were measured with films. The four square intensity pattern was delivered using step and shoot and conventional delivery techniques for comparison. Because of geometrical symmetry, the dose to each segment in this intensity pattern is expected to be the same when the same MU is assigned to each segment. An ionization chamber was used to measure the dose in the center of each of the four square segments. For the semi-Gaussian shaped profile, significant artifacts were observed when the profile was delivered with small MUs and/or at a high dose rate. For the four square intensity pattern, the dose measured in each segment presented a large variation when delivered with small MUs and a high dose rate. The variation increases as the MU/segment decreases and as the dose rate increases. These MU and dose rate dependencies were not observed when the intensity pattern was delivered using a conventional delivery technique. The observed distortion of the semi-Gaussian profile and dose variations among the segments of the four square intensity pattern are explained by considering the sampling rate and the communication time lag between the control systems. Finally, clinical significance is discussed. 相似文献
993.
994.
Auditory brainstem responses were recorded in normal children (NL) and children clinically diagnosed with a learning problem (LP). These responses were recorded to both a click stimulus and the formant transition portion of a speech syllable /da/. While no latency differences between the NL and LP populations were seen in responses to the click stimuli, the syllable /da/ did elicit latency differences between these two groups. Deficits in cortical processing of signals in noise were seen for those LP subjects with delayed brainstem responses to the /da/, but not for LPs with normal brainstem measures. Preliminary findings indicate that training may be beneficial to LP subjects with brainstem processing delays. 相似文献
995.
Genetics,genomics and gene discovery in the auditory system 总被引:15,自引:0,他引:15
Morton CC 《Human molecular genetics》2002,11(10):1229-1240
The sounds of silence have forever been broken as genetics and genomics approaches in human and model organisms have provided a powerful and rapid entry into gene discovery in the auditory system. An understanding of the complexities and beauty of the biological process of hearing itself is unfolding as genes underlying hereditary hearing impairment are identified. Genes involved in modifying hearing are also being found, and will be critical to a full comprehension of genotype-phenotype relationships. Investigations in the auditory system will provide important insight into how the nervous system decodes molecular information. Deafness represents a common sensory disorder that can interfere dramatically in the acquisition of speech and language in children, and in the quality of life for a growing aged population. As newborn screening for hearing impairment is being implemented in many birth hospitals, the prospects for precise clinical diagnosis, appropriate genetic counseling and proper medical management for auditory disorders has never been at a more exciting crossroad. 相似文献
996.
997.
Replacing a hospital's obsolete mainframe computer system with a modern integrated clinical and administrative information system presents multiple challenges. When the new system is activated in one weekend, in "big bang" fashion, the challenges are magnified. Careful planning is essential to ensure that all hospital staff are fully prepared for this transition, knowing this conversion will involve system downtime, procedural changes, and the resulting stress that naturally accompanies change. Implementation concerns include staff preparation and training, process changes, continuity of patient care, and technical and administrative support. This article outlines how the University of Missouri Health Care addressed these operational concerns during this dramatic information system conversion. 相似文献
998.
Burbank PM Reibe D Padula CA Nigg C 《Orthopaedic nursing / National Association of Orthopaedic Nurses》2002,21(4):51-61; quiz 61-3
The loss of muscle strength, decreased flexibility and range of motion, and decreased sense of balance that frequently accompany aging contribute to falls and functional decline. Even in advanced old age, one can improve strength, decrease the risk of falls, improve cardiorespiratory fitness, and improve ability to live independently. The Transtheoretical Model (TTM) of behavior change is an internationally recognized model that holds much promise for health behavior changes of all types. This article outlines the effects of exercise on age-related changes in the musculoskeletal system and describes the TTM as a model useful to help older adults change their exercise behavior. Research studies are documented that support the effectiveness of the TTM in changing behavior. Application of the model is described with specific examples illustrated in two case studies. 相似文献
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