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81.
Summary Eight men (20–23 years) weight trained 3 days week–1 for 19 weeks. Training sessions consisted of six sets of a leg press exercise (simultaneous hip and knee extension and ankle plantar flexion) on a weight machine, the last three sets with the heaviest weight that could be used for 7–20 repetitions. In comparison to a control group (n = 6) only the trained group increased (P<0.01) weight lifting performance (heaviest weight lifted for one repetition, 29%), and left and right knee extensor cross-sectional area (CAT scanning and computerized planimetry, 11%, P<0.05). In contrast, training caused no increase in maximal voluntary isometric knee extension strength, electrically evoked knee extensor peak twitch torque, and knee extensor motor unit activation (interpolated twitch method). These data indicate that a moderate but significant amount of hypertrophy induced by weight training does not necessarily increase performance in an isometric strength task different from the training task but involving the same muscle group. The failure of evoked twitch torque to increase despite hypertrophy may further indicate that moderate hypertrophy in the early stage of strength training may not necessarily cause an increase in intrinsic muscle force generating capacity. 相似文献
82.
The effects of training, immobilization and remobilization on musculoskeletal tissue 总被引:2,自引:0,他引:2
P. Kannus L. Jozsa P. Renström M. Järvinen M. Kvist M. Lehto P. Oja I. Vuort 《Scandinavian journal of medicine & science in sports》1992,2(4):164-176
Compared with the knowledge on immobilization, the effects of remobilization on musculoskeletal tissues have not been well established. What is sure is that remobilization and rehabilitation of any component of the musculoskeletal tissues require much more time than the time needed to cause the immobilization atrophy. With intensive rehabilitation, the functional properties of skeletal muscles can be improved significantly even years after the injury and following immobilization, but no study has shown whether full recovery is possible and whether these rehabilitated muscles are able to respond normally to further training. Experimental studies have given evidence that slow-twitch muscle fibres have better capacity for recovery than fast-twitch fibres, most likely due to better circulation and higher protein turnover. Also evidence has been given that fibre regeneration is possible through satellite cell activation and myotube formation. Very little is known, however, about the effects of age, gender or the level of preimmobilization muscle performance on the restoration capacity. Also the fate of the marked structural changes (for example, connective tissue accumulation) induced by immobilization is unknown. Tendon and ligament tissues are likely to respond appropriately to remobilization, resulting in acceleration of collagen synthesis and fibril neoformation. However, there is a strong suspicion that remobilized tendons and ligaments will not achieve all the biochemical and biomechanical properties of their healthy counterparts. Specifically, the amount of weak type III collagen has been shown to be overrepresented in these tissues instead of mature, strong type I collagen. It is not known whether this is an important risk factor for ruptures during later activity. The effects of remobilization on muscle-tendon junction and proprioceptive organs are not known. It would not be surprising if the serious structural changes induced by immobilization were unrestorable. In the literature dealing with immobilization and remobilization, cartilage degeneration is always a major concern, because not only too strenuous training or immobilization, but also unskilful remobilization may activate this process leading finally to osteoarthrosis. Bone may be one of the best components of musculoskeletal tissues to respond to remobilization, probably because the immobilization atrophy of bone is largely quantitative (osteoporosis) only. The prerequisites for bony recovery are that the follow-up time is long enough (months) and that immobilization has not exceeded about 6 months, the time limit between active and inactive (irreversible) osteoporosis. Prevention of the atrophying effects of immobilization can be very successful if performed properly. According to present knowledge, there are many methods for the purpose, including preimmobilization training early, controlled mobilization; optimal positioning of the immobilized joint; muscular training during immobilization; early weightbearing; exercise with the nonimmobilized extremity; and electrical stimulation. Lots of education and information will be needed, however, before these methods are deeply rooted in the daily routines of the attending physicians, physical therapists, athletic trainers and other persons involved in the treatment of musculoskeletal problems. 相似文献
83.
心绞痛PTCA术后患者以步行为主的康复训练 总被引:4,自引:0,他引:4
14例不稳定性心绞痛患者,男性12例,女性2例,平均年龄55岁,均因药物治疗无效而进行PTCA治疗。总计16个血管段、前降支9段,回旋支4段,右冠状动脉3段。术后执行以步行为主要内容的一周康复训练程度,全部病例均顺利完成,表明以步为主的非监护康复训练对不稳定性心绞痛PTCA术后和是安全可行的。 相似文献
84.
提高护士病情观察能力的培训方法与效果 总被引:1,自引:0,他引:1
目的提高护士对病人病情观察的能力。方法针对护士观察病情方面存在的问题,制定对策,进行专业知识培训,制订考核标准,加强考核力度。结果培训后护士病情观察能力、病区护理质量有明显提高(P<0 05或 P<0.01)。结论加强培训可以提高护士病情观察能力,提高护理质量。 相似文献
85.
86.
Eli Peli 《Ophthalmic & physiological optics》2005,25(6):543-555
Subjects with central field loss (CFL) individually selected enhancement parameters to improve visibility of static video images. The effect of enhancement on performance and on perceived quality of motion video was assessed. Performance, e.g. recognition of visual details, was assessed by having subjects answer questions regarding visual information contained in the video motion segments that were enhanced using the individually-selected parameters. Enhancement did not improve subject performance on questions about video content. This result might be due to a ceiling effect limitation of the performance assessment method. In a second procedure, subjects' continuous perceptions of quality (using an adjective-based rating scale) were made while the enhancement parameters were abruptly switched among multiple values; these included the individually-selected enhancements, as well as unenhanced, over-enhanced, and degraded segments. The results indicate that adaptive enhancement (individually-tuned using a static image) adds significantly to perceived image quality when viewing motion video. Subjects who selected stronger contrast enhancement also perceived the enhancement to provide a larger benefit in image quality. 相似文献
87.
88.
脑卒中偏瘫康复训练程序化研究 总被引:4,自引:0,他引:4
目的 :观察脑卒中偏瘫患者进行康复训练的疗效。方法 :2 2例脑卒中患者 :康复组 12例 ,对照组 10例。 2组均接受神经科常规药物治疗。康复组按“中风后程序化康复训练表”进行康复训练 ,分别于康复前、康复后 1月和 3月进行疗效评定。结果 :日常生活活动能力量表 (ADL)测评结果显示 :康复组有效率 83 3% (10 / 12 ) ,对照组 30 % (3/10 ) ,2组差别有显著意义 (P <0 0 5 )。神经功能缺损评分结果显示 :康复组有效率 91 7% (11/ 12 ) ,对照组 4 0 % (4 / 10 ) ,2组差别有显著意义 (P <0 0 1)。结论 :康复训练能降低脑卒中偏瘫患者的致残率 ,提高生活质量。 相似文献
89.
90.