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91.
探讨DR颈椎斜位影像中应用组织均衡技术的优势 总被引:4,自引:0,他引:4
目的探讨颈椎斜位直接数字化X线摄影(direct digital radiography,DR)中,采用组织均衡技术的DR图像与标准DR图像的差别。方法利用中国医科大学附属第一医院引进的GE—Revolution XQ/Ⅰ型DR机对所摄的颈椎斜位影像中随机抽取100例作为分析资料。应用组织均衡技术对图像进行处理,同时与标准DR图像进行比较。结果应用组织均衡技术的图像,同一幅图像上不同部位的细节均可清晰显示;标准DR图像需调节不同的窗宽、窗位才能清晰显示或不能显示不同体厚部位的细节。结论在直接数字化X线摄影中,应用组织均衡技术能明显改善因受体厚度影响而难于观察部分的可视性,同时又不牺牲其他部分的细节显示,使DR的应用更完美。 相似文献
92.
目的:探讨国产吻、缝合器在超低位直肠前切除术中的应用。方法:对27例直肠癌患者行超低位直肠前切除,应用上海产金钟牌缝合器、吻合器,进行结肠-直肠吻合。结果:本组根治性切除25例(92.6%);1例发生吻合口瘘,发生率为3.7%;吻合口狭窄3例,发生率为11.1%,均经保守治疗治愈。结论:合理使用国产缝合器、吻合器可完成超低位直肠癌的保肛手术,可达保肛、根治、降低费用、减少并发症的目的。 相似文献
93.
胡薇 《山西职工医学院学报》2000,(4)
目的:探讨如何处理持续性枕后位,以尽可能减少母儿并发症。方法:总结分析了120例持续性枕后位的孕周、胎儿体重、产重长短对分娩方式的影响以及不同分娩方式对母儿的影响。结果:当孕周大于等于40周,胎儿体重大于等于3500g,潜伏期大于8h,活跃期大于4h时,剖宫产率明显增高,持续性枕后位所致的产程延长及手术助产增加了新生儿窒息率和产妇的并发症。结论:对持续性枕后位应正确观察处理各产程,早期诊断,充分估计其阴道分娩的可能性,对不适于阴道分娩者,应果断行剖宫产术,以降低母儿并发症。[ 相似文献
94.
运用轨道的有限单元模型,采用荷载增量法,计算了低温条件下大型养路机械维修超长无缝线路对钢轨应力和锁定轨温的影响。计算结果表明,大型机械在一次性起道时会对钢轨产生较大的应力,建议一次性起道量不超过40mm。 相似文献
95.
A new generation of intelligent systems is growing up in the community of Artificial Intelligence in Medicine. The main goal
of these systems is the representation and use of real theory of diseases, as they are represented in medical textbooks or
in scientific articles, rather than the heuristic shortcuts of human experts. In this paper, we will argue that the difficulties
in the integration of basic science and clinical knowledge in intelligent systems arise from ontological differences between
these kinds of knowledge and that the solution can be found in their dynamic integration during the reasoning process. In
order to illustrate this point, we will first describe an epistemological analysis of the interplay between basic science
knowledge and clinical knowledge, and then we will provide the example of a computational architecture implementing this view.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
96.
SUMMARY Previous studies have shown that premature infants may be at risk for hypoxemia and bradycardia when placed in standard car seats. However, the relationship of such breathing abnormalities to sleep state have not been studied. The purpose of the present study was to investigate the effect of car seat positioning on respiratory patterns in preterm infants during sleep and to evaluate their relationship to sleep state. Complete polysomnography, including sleep and breathing parameters, was performed on twenty-eight premature infants. Each infant was randomly assigned to the car seat or prone (crib) position for the first recording period. Following the recording of at least two sleep cycles, the position was reversed. The percentage of active and quiet sleep was calculated and breathing parameters were measured. In the car seat, the infants spent significantly more time in active sleep and less time in quiet sleep than in the prone position, of the respiratory parameters, periodic breathing (PB) was significantly higher in the car seat. The presence of at least one abnormal breathing events (bradycardia, desaturation, PB apnoea) was also significantly higher in the car seat. An analysis of variance (ANOVA) of PB revealed significant sleep-state effect (active vs. quiet sleep), but no significant condition or interaction effects, indicating that PB was more frequent in active sleep regardless of the sleeping condition. It is concluded that increased active sleep in the car seat condition, rather than the positioning of the infant in the seat per se, may account for the increase in periodic breathing and possibly other breathing abnormalities reported in car seats. 相似文献
97.
The effects of a series of benzodiazepine (BZ) receptor ligands, ranging from a full agonist through to partial inverse agonists, were examined on short term working memory in the rat. The behavioural paradigm used was a discrete trial, operant delayed matching to position task, as originally described by Dunnett (1985), with delays of 0, 5, 15 and 30 s. The benzodiazepine receptor (BZR) full agonist lorazepam (0.25, 0.375 and 0.5 mg/kg) dose and delay dependently impaired matching accuracy. Lorazepam also increased the latency to respond and decreased the number of nose pokes made into the food tray during the delays. In contrast, the BZR partial agonist ZK 95 962 (1, 3, 10 mg/kg) did not affect matching accuracy, but did increase the speed of responding. The BZR antagonist ZK 93 426 (1.25, 5, 25 mg/kg) had no effects in this paradigm. The BZR weak partial inverse agonists Ro 15-4513 (0.1, 1 and 10 mg/kg) and ZK 90 886 (1, 3 and 10 mg/kg) did not affect accuracy of performance. However, both of these drugs increased the latency to respond and decreased nose poke responses. These motoric effects were particularly strong following 10 mg/kg Ro 15-4513. This shows that the effects of drugs on the accuracy of responding and on the speed of responding can be dissociated. The BZR partial inverse agonist FG 7142 had effects on matching accuracy that were dependent upon dose. The lowest dose of FG 7142 (1 mg/kg) significantly improved accuracy, whereas the highest dose (10 mg/kg) impaired accuracy. This impairment induced by FG 7142 (10 mg/kg) was accompanied by an increase in the latency to respond and a decrease in the number of nose pokes. Taken together, these results show that the accuracy of delayed matching performance can be modulated in opposite ways by the BZR full agonist lorazepam and a low dose of the BZR partial inverse agonist, FG 7142. 相似文献
98.
99.
The genesis of immune privilege high in the evolutionary tree suggests that immune privilege is necessary, if not advantageous for the progressive development of the CNS. Upon reaching a certain degree of complexity, it seems as if the CNS was obliged to restrain the immune system from penetrating the blood-brain barrier. CNS autoimmunity against myelin proteins is known to be a contributory factor in the pathophysiology of multiple sclerosis and in the animal model of experimental autoimmune encephalomyelitis (EAE) (Wekerle, 1993). Such autoimmunity has therefore been regarded as detrimental and hence obviously undesirable. However, recent findings in our laboratory suggest that T-cell autoimmunity to CNS self-antigens (Moalem et al., 1999), if expressed at the right time and the right place, can do much good in the CNS. We shall review the experiments briefly, and then discuss their implications for our understanding of immune privilege and CNS maintenance after injury. 相似文献
100.
Summary
Since 1995 German health maintenance laws require hospitals to document and code all referals, admissions and discharges using
the 4-digit ICD. Operative procedures are documented and coded using the ICPM. Beginning in January 1996, reimbursement for
health services requires a diagnosis-related billing and payment for special procedures. The decision for billing is based
on documented diagnosis and therapy. This extended request for documentation makes an online access to diagnosis and therapy
with a computer-assisted coding system advisable. In 1996 in our hospital each diagnosis and operation was manually documented
and coded on a form. Since the beginning of 1997, documentation and coding has been exclusively computer-assisted. On the
basis of documented diagnosis and therapy the computer provides the route of reimbursement. Retrospectively we evaluated the
number of charged diagnosis-related billings and payments for special procedures from January to April of 1996 and 1997. It
became evident that with computer-assisted documentation and coding the number of detected and charged diagnosis-related billings
and payments for special procedures was significantly increased in comparison with the previous year.
相似文献