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21.
As a consequence of the time-varying magnetic field induced by eddy currents, frequency drifting occurs when the sampling window of localized spectroscopy continuously shifts. The frequency drifting and the concomitant phase variations can severely affect spectroscopy results when data are acquired with multiple echo times (TEs), such as in the measurement of glutamate (Glu) concentration using the TE-averaged method. Specifically, the averaged spectra are further broadened and distorted in the presence of residual eddy currents, and editing of the coupled spins of Glu C4 protons is affected, resulting in errors in the measured relative intensity ratio. Postacquisition correction using unsuppressed water as reference can effectively minimize this detrimental effect, as manifested by the significantly enhanced signal intensity. Also, it is demonstrated that the methyl signals of creatine (Cr) at 3.0 ppm and choline (Cho) at 3.2 ppm can be used as internal references in finding frequency and phase disparities between different TEs. 相似文献
22.
Janet Fricke Carolyn Unsworth Diane Worrell 《Australian Occupational Therapy Journal》1993,40(1):7-15
This paper reports an inter-rater reliability study on the Functional Independence Measure (FIM). The FIM measures inpatient burden of care, as reflected in 18 self care items, rated on a seven point scale from dependent to independent. The subjects were 40 occupational therapists, divided according to experience with the FIM and randomly assigned to a FIM training or non-training group. Subjects rated video tapes of four stroke patients on transfers, bathing, dressing, grooming, toileting and eating items from the FIM. Rater consensus was calculated using the intraclass correlation coefficient (ICC), percentage agreement and a measure of disagreement. Rating accuracy was measured by comparisons with an expert rater. Ratings were most reliable when done by clinicians with no prior FIM experience, from the FIM training group. It is strongly recommended that all clinicians undergo FIM training before using this tool to ensure acceptable reliability. 相似文献
23.
Annotation: Aspects of Pain in Children and Adolescents 总被引:2,自引:0,他引:2
《Journal of child psychology and psychiatry, and allied disciplines》1995,36(5):717-730
24.
用2‰游标卡尺对114具L1~L5段椎骨标本进行测量,包括椎孔上缘矢径及下缘矢径的距离和相互关系。结果:腰椎孔下缘矢径明显大于上缘矢径(P<0.01),腰椎孔下缘矢径明显大于腰椎孔中矢径。为腰椎管狭窄的临床诊断提供解剖学基础。 相似文献
25.
Adolescent stress is an emerging area of importance in considerations of the health of young people. Exposure to stress predicts a range of both physical and mental health problems in adolescents and relates, as well, to the initiation of important health risk behaviours. Yet the measurement of stress in adolescents has been as fraught with methodological difficulty as it has been for adults. This paper examines the Adolescent Stress Questionnaire (ASQ) which was developed specifically to address the domain of stressors specific to adolescent experience and looks at three cohorts of responses to this questionnaire over time (1995, 1998 and 2001). It assesses the stability of the original 7‐factor structure of the ASQ over time, and while confirmatory factor analysis indicates that stability to be acceptable, it also suggests that either adolescent stressors themselves, or the language by which they are reported, vary sufficiently over time to warrant the refinement of the instrument. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
26.
Sylvain Miraux Jean-Michel Franconi Eric Thiaudière 《Magnetic resonance in medicine》2006,56(3):469-473
Blood velocity is a functional parameter that is not easily assessed noninvasively, especially in small animals. A new noninvasive method that uses magnetic resonance angiography (MRA) to measure blood flows is proposed. This method is based on the time-of-flight (TOF) phenomenon. By initially suppressing the signal from the stationary spins in the area of interest, it is possible to sequentially visualize only the signal from the moving spins entering a given volume. With this method, 3D cine images of the blood flow can be generated by positive contrast, with unparalleled spatial (<200 microm) and temporal resolutions (<10 ms/image). As a result, it is possible to measure flow in sinuous paths. The present method was applied in vivo to measure the blood velocity in mouse carotid arteries. Because of its robustness and simplicity of implementation, this method has numerous potential applications for fundamental studies in small animal models. 相似文献
27.
Phoebe S. Y. Lo Michael C. F. Tong Dennis A. Revicki Ching Chyi Lee John K. S. Woo Henry C. K. Lam C. Andrew van Hasselt 《Quality of life research》2006,15(5):877-887
Background: The Rhinitis Symptom Utility Index (RSUI), originally developed in the United States, consists of a patient-preference weighting
scheme and a 10-item questionnaire measuring the severity and frequency of rhinitis related symptoms over a 14-day period.
This study aimed to determine whether the Chinese RSUI could adopt the US-based multi-attribute utility function (MAUF) in
scoring rhinitis symptoms. Methods: In a Hong Kong study, 116 Chinese adults with allergic rhinitis completed the RSUI questionnaire and 36-item Short-Form
Health Survey (SF-36) after they had been seen by two otorhinolaryngologists for disease-severity ratings. Respondents then
completed computer-administered direct preference measures, i.e., visual analogue scale (VAS) and standard gamble (SG) assessments.
The VAS and SG data were used to estimate a MAUF for the Chinese-based RSUI. Results: The derived MAUF was somewhat different than the one developed for the US RSUI. Test–retest reliability for the Chinese
RSUI was satisfactory (ICC = 0.71, p<0.001). Scores differentiated among cases with mild, moderate, and severe symptoms (p<0.001); and between those who did and did not require medications to control symptoms (p = 0.031). Findings were significantly correlated with SF-36 domain scores (r = 0.19 to 0.37; p=0.041 to <0.001). When the US-based scoring function was applied to the Chinese subjects, the resulting mean RSUI score was
significantly lower (p<0.001). Comparisons between directly measured VAS and SG scores between the US and Chinese samples, demonstrated significant
differences (all p<0.05), with the US subjects consistently rating rhinitis symptoms as worse than Chinese subjects. Conclusions: The Chinese RSUI has good measurement properties that reflect patient preferences from the Chinese. Results suggest that
there are differences in preference rating between US and Chinese subjects and that use of the US-based preference function
for the RSUI would bias the measurement of rhinitis symptom outcomes in Chinese subjects. 相似文献
28.
29.
Major progress in clinical pain assessment and management has been achieved in the last decade. More effective analgesic drugs and improved techniques for pain management have been introduced. However, medical reports published during the last few years on postoperative pain management (POPM) indicate that moderate or even severe pain is still rather commonly experienced by surgical patients in the early postoperative period and that worst-pain-episodes may occur even in the late postoperative phase. Insufficient relief of postoperative pain seems a more common problem on surgical wards than on a postanaesthesia care unit (PACU). The aims of POPM are to inhibit autonomic trauma-induced nociceptive impulses that may result in functional disturbances of vital organs and thereby affect the incidence of potentially severe complications influencing clinical outcome. Considering that recent studies continue to show sub-optimal pain management despite the availability of effective drugs and analgesic techniques it must be considered essential to identify possible barriers to effective pain management in clinical practice so that necessary improvements in POPM routines can be carried out. 相似文献
30.
[目的]比较国人正常膝关节与髌骨不稳膝关节的髌腱长度,探讨国人髌腱长度的测量在髌骨不稳诊断中的意义。[方法]2003年1月~2005年12月诊治的43例髌骨不稳患者共49膝(男15例,女28例,6例为双侧髌骨不稳);平均年龄21.4岁(18~28岁);平均身高163(155~173)cm。正常对照组为50例健康体检者共50膝(男16例,女34例);平均年龄24.2岁(18~35岁);平均身高165(154~177)cm。在屈膝30°X线侧位片上测量髌腱长度、胫骨结节至胫骨平台的距离、Insall-Salvati指数。[结果]髌骨不稳组髌腱长度为(53.3±2.7)mm,对照组为(47.3 3.3)mm,统计学上具有显著差异性(P<0.05)。Insall-Salvati指数在髌骨不稳组(1.33±0.17)和对照组(1.06±0.14)也具统计学差异(P<0.05)。胫骨平台与胫骨结节之间的距离在髌骨不稳组为(27.8±3.6)mm,对照组为(28.9±4.1)mm,统计学上无显著性差异(P<0.05)。[结论]髌腱长度过长是髌骨不稳的重要特点之一。联合测量髌腱长度和Insall-Salvati指数有助于髌骨不稳的诊断。 相似文献