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121.
目的:探讨马利兰导致继发再障的原因及安全使用马利兰的方法。方法:通过6例因慢粒而使用马利兰治疗后导致继发再障临床资料分析。结果:马利兰导致继发再障与药物剂量、用药时间及个体敏感性有关。结论:遵循小剂量、长疗程的原则使用马利兰治疗慢粒,可减少继发再障的发生。 相似文献
122.
Alternating poly(Glu-Leu) was synthesized by the condensation of the corresponding dipeptide p-nitrophenyl ester at high concentration. It exhibits a random coil structure in pure water at neutral pH. Addition of monovalent cations, such as NH+4 to a final 0.1 M solution, induces a transition to a water soluble β-structure. The salt effect is quite selective since no transition was observed with Li+, Na+ or Cs+ ions. Addition of 0.5 equiv. of calcium, cobalt or manganese chlorides per glutamyl residue induces similar coil to β-sheet transitions. No polymer precipitation was observed at these very low salt concentrations. Addition of 0.5 equiv. of Cu2+ or 0.15 equiv. of Fe3+ induces a coil to α-helix transition. Molecular modeling has been used to understand tentatively the main factors controlling the different conformations observed with the various metal ions. © Munksgaard 1997. 相似文献
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INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
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126.
6-取代苯基哒嗪的3位γ-氨基丁酸衍生物的合成及抗惊活性 总被引:1,自引:0,他引:1
GABA的合成类似物是开发新型抗惊剂和抗癫痫药物的新领域。由芳香醛与吗啉、氰化钾反应形成的α-芳基-α-(4-吗啉)乙腈,可对α,β-不饱和腈或酯进行1,4-加成,生成1,4-酮酸型化合物。此物与肼缩合,再经芳构化即得6-芳基-3(2H)哒嗪酮。后者再经氯化后。与GABA缩合,制备3-(N-GABA)-6-芳基哒嗪类及其分子内脱水产物3-(N-丁内酰胺)-6-芳基哒嗪类化合物。本文应用此法合成了17个上述苯代哒嗪的GABA衍生物,并初步测验了它们的抗惊(MES)活性。活性最强的是3-(N-GABA)-6-(2′,4′-二氯苯基)哒嗪(ED50=21.05mg/kg)。 相似文献
127.
4-甲氧羰基-4-N-丙酰苯胺基哌啶1位衍生物的合成及其镇痛作用 总被引:2,自引:0,他引:2
本文报道了一系列N-[-1(2-苯乙基-4-甲氧羰基-4-哌啶基]-N-丙酰苯胺(4-甲氧羰基芬太尼)哌啶环1位取代衍生物的合成及其镇痛活性;讨论了结构与镇痛活性之间的关系。药理试验结果表明,大部分化合物具有典型的吗啡样镇痛活性,是一类作用极强的麻醉性镇痛剂。特别是哌啶环1位β-苯环被取代乙烯基替代的化合物具有相当或接近子母体化合物的镇痛活性。其代表物1321的镇痛活性(ED_(50)=0.005mg/kg ip,小鼠,热板法)略强于4-甲氧羰基芬太尼(ED_(50)=0.0063 mg/kg)。 相似文献
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129.
Samantha Higgins Sarah Parsons Noel Woodford Matthew Lynch Christopher Briggs Chris O’Donnell 《Forensic science, medicine, and pathology》2017,13(3):317-327
The purpose of this study was to investigate the impact of post-mortem computed-tomography angiography (PMCTA) on the histology of the liver, kidneys and heart. Multiple tissue cores were collected from the liver, left and right kidneys and left ventricle utilizing CT-guided biopsy. Subsequent whole body PMCTA was performed using a solution of polyethylene glycol and iodinated radiographic contrast, and an embalming pump. Corresponding biopsy cores were collected at autopsy, and blinded histology analysis assessing for PMCTA-induced histology artefact was performed. The blinded analysis of pre-PMCTA and post-PMCTA biopsy samples demonstrated that whole body PMCTA had no effect on the histological analyses of the liver (0%, CI = 0–13.7%), left ventricle of the heart (0%, CI = 0–36.9%) and right kidney (0%, CI = 13.2%), however likely caused increased Bowman’s capsule spaces in the left kidney of one case (4%, CI = 0.01–20.4%). Other artefactual histological changes identified included eosinophilic material in the liver, whiter interstitium and dilated tubules in kidney samples, and autolysis-related changes, however these could not be categorically attributed to the PMCTA procedure. PMCTA causes zero or minimal effect to the histological examination of the liver, left kidney, right kidney and left ventricle, and as such performing PMCTA prior to autopsy is unlikely to impact autopsy histological results in these organs. 相似文献
130.