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51.
目的 :观察高血压患者在监护拔牙过程中血压、心率、心电图变化及手术应激反应的年龄差异 ,探讨安全科学的监护方法。方法 :对 739例高血压患者监护拔牙的临床资料进行回顾性分析。观察高血压患者和不同年龄组高血压患者麻醉前、中、后 ,拔牙中、拔牙后 ,血压、心率变化。结果 :高血压组血压、心率比对照组显著增高、加快 (P <0 .0 1) ;80岁以上年龄组收缩压显著升高 (P <0 .0 1) ,4 9岁以下年龄组收缩压显著降低 (P <0 .0 5 ,P <0 .0 1)。结论 :各种高血压患者特别是高龄高血压患者 ,在分时安全管理下可以接受无痛拔牙。 相似文献
52.
以氯化亚铁和甘氨酸为原料,研究了甘氨酸螯合铁的合成工艺条件.结果表明,pH值、配位比以及抗氧化剂用量对产品组成和得率有很大影响.确定了螯合的最适条件为:pH值为5.5、配位比为4∶1.采用有机溶剂萃取法,使甘氨酸螯合铁在无水乙醇中以沉淀的方式析出,实现甘氨酸螯合铁与无机铁的分离.讨论了萃取时有机溶剂用量对产品得率的影响,在无水乙醇与滤液的体积比为9∶1时,亚铁得率最高. 相似文献
53.
目的将微波辅助提取新技术应用于茯苓水溶性多糖的提取,寻求最佳提取工艺。方法采用均匀优化设计试验条件,以苯酚-硫酸法测定样品中多糖含量。对超声辅助提取和传统水提法比较,并对水解前后的微波提取多糖衍生物用毛细管电泳检测。结果最佳提取条件:时间为18min;固液比为1:50;微波占空比42%,此时提取率为2.792%。优于传统。结论微波辅助提取速度更快、提取效率更高;毛细管电泳检测表明微波提取茯苓多糖过程合理,能得到较理想的提取物。 相似文献
54.
用十六烷基-二甲基-乙基-溴化铵(CTAB)法快速高效地从样品中提取了可供分析的基因组DNA,经PCR扩增,鉴定了含有35S启动子和NOS终止子的转基因样品.该方法的灵敏度可达0.1%,并且具有很好的稳定性. 相似文献
55.
56.
Purpose. Hydrophilic and charged solutes have a lower membrane permeability which is due to a lower partition into the lipid membrane (low solubility in the membrane phase) and/or a slower transcellular diffusion coefficient. They are therefore anticipated to be absorbed through the paracellular route, which is a consequence of diffusion and a convective volume flow through the water-filled intercellular space.
Methods. Two approaches have been used to investigate the mechanisms underlying the paracellular drug transport across the intestinal mucosa: (a) including water transport by exposing the apical side of the epithelium with a hypotonic solution, and (b) stimulated paracellular transport by widening of tight junction and increased water absorption as a consequence of the sodium-coupled transport of nutrients.
Results. Among the first studies that recognized this fluid flux dependent transmucosal transport of drugs, was one published by Oschenfahrt & Winne in 1973 and the one by Kitazawa et al. in 1975. During the last two decades the importance of this paracellular route for drug delivery have been explored in vitro and in situ.
Conclusions. The limits concerning molecular weight, shape, ionization and the effect of physiological stimulants, such as luminal concentrations of nutrients, osmolality and motility, are currently under investigation. However, recently published in vivo human data by ourselves and others indicate that the promising results obtained in vitro and in situ for various hydrophilic compounds might not be valid in quantitative aspects in humans, especially not for drugs with a molecular weight over 200. 相似文献
57.
高效液相色谱法测定人血浆中翁丹西隆浓度 总被引:1,自引:0,他引:1
建立了翁丹西隆的高效液相色谱测定法。血浆样品用醋酸乙酯萃取,以ZorbaxSilica为固定相,60%0.025mol/L乙酸钠缓冲液(pH4.2)、40%乙腈为流动相,紫外310nm处测定。采用外标法峰高定量。最低检出浓度达1ng/ml,线性范围1.0~40.0ng/ml(r=0.9996),平均回收率为(95.22±3.58)%(RSD3.76%)。用本法测定人血浆中翁丹西隆浓度具有快速、简便、专一性和灵敏度高的优点。 相似文献
58.
Nicole C. Naus Gregorius P. M. Luyten Theo Stijnen Paul T. V. M. De Jong 《Documenta ophthalmologica. Advances in ophthalmology》1995,90(1):53-59
In this study we wanted to investigate the post-operative astigmatism and visual acuity after phacoemulsification and conventional extracapsular cataract surgery. Patients operated between April and June 1993 (n=150) were retrospectively analyzed. The patients were examined prior to surgery and at day 1, at day 10, and in week 6 post-operatively. The difference between the post-operative log mean visual acuity in the Phaco group and in the CECCE group was significant after 1 and 10 days, however it was not significant (p=0.191) after 6 weeks. The mean astigmatism was significantly less in the Phaco group than in the CECCE group during the whole post-operative check-up period. This study suggests that Phaco results in a lower post-operative astigmatism and an earlier visual rehabilitation compared to the CECCE technique.Abbreviations Phaco
Phacoemulsification
- CECCE
Conventional extracapsular cataract extraction 相似文献
59.
修订车间空气中溶剂汽油容许浓度的研究 总被引:1,自引:0,他引:1
通过对969例汽油作业工人的体格检查和对86个作业点760次车间内汽油浓度的测定结果表明,在达标的条件下,工人仍有神经衰弱,植物神经功能障碍的临床症状,说明现行车间的卫生标准应当进行修订。根据动物实验资料计算 MAC,180汽油为198.6mg/m~3,120汽油为225.0mg/m~3,二者相差不大,我们建议车间空气中溶剂汽油容许浓度可修订为200mg/m~3。 相似文献
60.
A membrane-coated fiber (MCF) array approach was developed for quantitative assessment of skin absorption from chemical mixtures, which was based on the similarity in the absorption mechanisms of the MCF membrane and the stratum corneum of the skin. A set of probe compounds were used to detect the relative molecular interaction strengths of chemicals with the vehicle and the membranes, which provided a linkage between the skin permeability (log k) and MCF partition coefficients (log KF). A predictive model was established via multiple linear regression analysis of the data matrix of experimentally measured log k value and log KFm values; log k=a0+a1 log KF1+a2 log KF2+...+an log KFm, where m is the number of diverse MCFs. Twenty-five probe compounds and three MCFs (polydimethylsiloxane for lipophilic, polyacrylate for polarizable, and CarboWax for polar interactions) were used to demonstrate the model development processes in the MCF array approach. The skin permeability of the probe compounds was measured with conventional diffusion cell experiments using dermatomed porcine skin. Three predictive models were established for skin permeability prediction from chemical mixtures in water, 50% ethanol, and 1% sodium lauryl sulfate (SLS) with R2 values of 93, 91, and 83, respectively. The log k and log KF values were considerably altered by the addition of ethanol or SLS into the dose vehicle; however, their correlations to skin permeability remained strong under various conditions. These results suggested that the experimentally based MCF array approach can be used to predict skin absorption from chemical mixtures in different vehicles or formulations. 相似文献