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排序方式: 共有1675条查询结果,搜索用时 46 毫秒
991.
目的通过对社区获得性肠杆菌肺炎与普通肺炎的临床对比研究,探讨社区获得性肠杆菌肺炎新的流行病学变化趋势及其特点。方法10例社区获得性肠杆菌肺炎与20例社区获得性普通肺炎进行配对研究,回顾性分析其临床特点、易患因素、病原学检查特点以及抗生素治疗特点。结果(1)社区获得性肠杆菌肺炎的临床症状、生化检查、胸部X线表现等无特殊性,两组病死率比较差异无显著性。(2)患有基础疾病者易发生社区获得性肠杆菌肺炎。(3)不适合抗生素使用时间的过度延长引起一个复杂的疾病过程,而适合抗生素使用的延迟未引起患者病死率的明显增加。结论(1)对因社区获得性肺炎住ICU的患者,如果具备年老,至少有一种基础疾病存在,有既往住院史,有既往抗菌素使用史等特点,应警惕社区获得性肠杆菌肺炎的可能。(2)对疑诊患者早期病原学检查有助于抗生素的合理的选择。 相似文献
992.
Margot H Uijterwaal Viola MJ Verhoef Peter JF Snijders 《Expert review of molecular diagnostics》2014,14(3):245-248
Several studies have shown that the human papilloma virus (HPV) test is a more sensitive and objective primary cervical cancer screening tool than cytology. Therefore, conversion of cytology into HPV screening (as is planned in The Netherlands and some other European regions) will result in a better protection against cervical cancer and high-grade precursor lesions. Moreover, offering self-sampling for HPV testing will increase screening attendance by re-attracting former non-attendees. However, triage of HPV positive women is necessary because the specificity of HPV testing is 2–4% lower than of cytology. Several triage strategies have been evaluated, of which two, with cytology testing included, are feasible and were recently recommended. As an alternative for cytology triage, objective, non-morphological disease markers are upcoming and so far have shown promising results. Finally, HPV testing can also contribute to a more efficient monitoring of women treated for high-grade cervical precursor lesions, permitting fewer follow-up visits. 相似文献
993.
广西藤茶中黄酮类成份的提取工艺研究 总被引:18,自引:0,他引:18
目的:提取分离藤(Ampelosis grossdentata)中的双氢杨梅树皮素(dihydromyricetin)和杨梅素(Myricetin)。方法:采用新的水提取和溶剂分离的方法,经化学和光谱鉴定确定结构。结果:提取产物经确证为双氢杨梅树皮素(dihydromyricetin)和杨梅素(Myricetin),平均收率分别为19.6%和0.51%。结论:该提取法经济、简便,易于操作并且提取率 相似文献
994.
Marvin Reuter Mariann Rigó Maren Formazin Falk Liebers Ute Latza Stefanie Castell Karl-Heinz J?ckel Karin Halina Greiser Karin B Michels Gérard Krause Stefan Albrecht Ilter ?ztürk Oliver Kuss Klaus Berger Benedikt MJ Lampl Michael Leitzmann Hajo Zeeb Karla Romero Starke Sabine Schipf Claudia Meinke-Franze Wolfgang Ahrens Andreas Seidler Bianca Klee Tobias Pischon Andreas Deckert B?rge Schmidt Rafael Mikolajczyk André Karch Barbara Bohn Hermann Brenner Bernd Holleczek Nico Dragano 《Scandinavian journal of work, environment & health》2022,48(7):588
995.
Olga C Damman Michelle Hendriks Jany Rademakers Diana MJ Delnoij Peter P Groenewegen 《BMC public health》2009,9(1):423-14
Background
To date, online public healthcare reports have not been effectively used by consumers. Therefore, we qualitatively examined how healthcare consumers process and evaluate comparative healthcare information on the Internet. 相似文献996.
N Rintiswati Y Mahendradhata Suharna Susilawati Purwanta Y Subronto CM Varkevisser MJ van der Werf 《BMC public health》2009,9(1):158
Background
Many tuberculosis (TB) patients in Indonesia are diagnosed late. We seek to document patient journeys toward TB diagnosis and treatment and factors that influence health care seeking behavior. 相似文献997.
化学修饰为小干扰RNA(siRNA)治疗面临的诸多挑战提供了解决方法。此综述考察现有的各种siRNA修饰方法,包括RNA和双链siRNA结构的各个方面。然后考察化学修饰siRNA的应用,重点关注其作用的专一性(消除免疫反应和杂交依赖性的脱靶作用)和转运方法,同时对酶稳定性和效价也进行了讨论。 相似文献
998.
MJ Jugus JP Jaworski PB Patra J Jin DM Morrow NJ Laping RM Edwards KS Thorneloe 《British journal of pharmacology》2009,158(1):372-381
Background and purpose:
Cyclooxygenase inhibitors function to reduce levels of prostaglandin E2 (PGE2) and are broadly efficacious in models of bladder overactivity. We therefore investigated a regulation of urinary bladder function in conscious rats by modulation of the EP3 receptor for PGE2.Experimental approach:
The activity of the EP3 receptor agonist GR63799X, and EP3 receptor antagonists, CM9 and DG041, at recombinant EP3 receptors was evaluated in vitro. In vivo, intraduodenal dosing during conscious, continuous-filling cystometry of spontaneously hypertensive rats was utilized to determine the urodynamic effect of EP3 receptor modulation.Key results:
GR63799X dose-dependently (0.001–1 mg·kg−1) reduced bladder capacity, as indicated by a reduction in both the micturition interval and volume of urine per void. In contrast, CM9 (10 and 30 mg·kg−1) and DG041 (30 mg·kg−1) enhanced bladder capacity, as indicated by significantly longer micturition intervals and larger void volumes. CM9 and DG041 inhibited the responses to GR63799X supporting the in vivo activity of these pharmacological agents at the EP3 receptor. In addition to its effect on bladder capacity, GR63799X increased endogenous urine production. Intra-arterial infusion of saline mimicked the enhancement of urine flow observed with GR63799X, and the response was inhibited by CM9.Conclusions and implications:
These data support the EP3 receptor as a modulator of urinary bladder activity in the conscious rat, and in addition, indicate a role for EP3 receptor activity in regulating urine flow. 相似文献999.
CZ Zhu JP Mikusa Y Fan PR Hollingsworth M Pai P Chandran AV Daza BB Yao MJ Dart MD Meyer MW Decker GC Hsieh P Honore 《British journal of pharmacology》2009,157(4):645-655
Background and purpose:
Activation of cannabinoid (CB) receptors decreases nociceptive transmission in inflammatory or neuropathic pain states. However, the effects of CB receptor agonists in post-operative pain remain to be investigated. Here, we characterized the anti-allodynic effects of WIN 55,212-2 (WIN) in a rat model of post-operative pain.Experimental approach:
WIN 55,212-2 was characterized in radioligand binding and in vitro functional assays at rat and human CB1 and CB2 receptors. Analgesic activity and site(s) of action of WIN were assessed in the skin incision-induced post-operative pain model in rats; receptor specificity was investigated using selective CB1 and CB2 receptor antagonists.Key results:
WIN 55,212-2 exhibited non-selective affinity and agonist efficacy at human and rat CB1 versus CB2 receptors. Systemic administration of WIN decreased injury-induced mechanical allodynia and these effects were reversed by pretreatment with a CB1 receptor antagonist, but not with a CB2 receptor antagonist, given by systemic, intrathecal and supraspinal routes. In addition, peripheral administration of both CB1 and CB2 antagonists blocked systemic WIN-induced analgesic activity.Conclusions and implications:
Both CB1 and CB2 receptors were involved in the peripheral anti-allodynic effect of systemic WIN in a pre-clinical model of post-operative pain. In contrast, the centrally mediated anti-allodynic activity of systemic WIN is mostly due to the activation of CB1 but not CB2 receptors at both the spinal cord and brain levels. However, the increased potency of WIN following i.c.v. administration suggests that its main site of action is at CB1 receptors in the brain.British Journal of Pharmacology (2009) 157, 645–655; doi:10.1111/j.1476-5381.2009.00184.x; published online 3 April 2009 相似文献1000.