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81.
Journal of Digital Imaging - Although medical imaging is frequently used to diagnose diseases, in complex diagnostic situations, specialists typically need to look at different modalities of image... 相似文献
82.
Recombinant human epidermal growth factor (rhEGF), a polypeptide of 53 amino acid residues, is subject to degradation by numerous
enzymes, especially proteases, when it is applied on the skin for the treatment of open wound. Amastatin, aprotinin, bestatin,
EDTA, EGTA, gabexate, gentamicin, leupeptin, and TPCK were investigated for the possible protease inhibitors, which may use
to protect rhEGF from degradation by the enzymes in the skin. Skin homogenates containing protease inhibitors and rhEGF were
incubated at 37°C for 30 minutes. After the reaction was stopped with trifluoroacetic acid, the amount of rhEGF remaining
in the sample was determined with an HPLC method. The percentages of rhEGF degraded, at the skin/PBS ratio of 0.25, in the
mouse, rat, and human skin homogenate were 85%, 70%, and 46%, respectively. The degree of degradation of rhEGF in the cytosolic
fraction was higher than that in the membrane fraction and these enzyme reactions were completed in 30 minutes. Bestatin,
EGTA, and TPCK showed significant inhibitory effects on the degradation of rhEGF in the two fractions (p<0.05), while the
other protease inhibitors had no significant inhibitory effects or, even resulted in deleterious effects. Therefore, the formulation
containing one or several inhibitors among these effective inhibitors would be a promising topical preparation of rhEGF for
the treatment of open wound. 相似文献
83.
环枕关节脱位:附二例报告 总被引:1,自引:0,他引:1
环枕脱位十分少见。此种病例,由于环枕部结构复杂,照片显示常不够清楚。人们往往只注住只注意环枢椎的关系而对环枕脱位的警惕性不足,容易漏诊,其后果是严重的。本文报道两例环枕关节脱位病例,并对该病的病因、发病机制、局部解剖、合并症及其诊断要点进行分析,并提出“斜坡-齿突线”对本病的诊断有重要意义。 相似文献
84.
Xu H Lu YF Partilla JS Zheng QX Wang JB Brine GA Carroll FI Rice KC Chen KX Chi ZQ Rothman RB 《Synapse (New York, N.Y.)》1999,32(1):23-28
Previous data obtained with the cloned rat mu opioid receptor demonstrated that the "super-potent" opiates, ohmefentanyl (RTI-4614-4) and its four enantiomers, differ in binding affinity, potency, efficacy, and intrinsic efficacy. Molecular modeling (Tang et al., 1996) of fentanyl derivatives binding to the mu receptor suggests that Asp147, Tyr148, Trp318, and His319 are important residues for binding. According to this model, Asp147 interacts with the positively charged opiate agonist to form potent electrostatic and hydrogen-bonding interactions. In this study, the role of weak electrostatic and hydrogen-bonding "pi-pi" interactions of the O atom of the carbonyl group and the phenyl ring structures of RTI-4614-4 and its four enantiomers with residues Tyr148, Trp318, and His319 were explored via site-directed mutagenesis. Tyr148 (in transmembrane helix 3 {TMH3}), Trp318 (TMH7), and His319 (TMH7) were individually replaced with phenylalanine or alanine. Receptors transiently expressed in COS-7 cells were labeled with [125I]IOXY according to published procedures. Mutation of Tyr148 to phenylalanine reduced the binding affinities of some mu-selective agonists (2-7 fold) but did not alter the affinities of DAMGO, naloxone, and the non-selective opiates etorphine and buprenorphine. In contrast, this mutation significantly increased the binding affinities (decreased the Kd values) of [D-Ala2,D-Leu5]enkephalin, IOXY, and dermorphin. Mutation of Trp318 decreased opioid receptor binding to almost undetectable levels. Substitution of alanine for His319 significantly reduced binding affinities for the opioid ligands tested (1.3- to 48-fold), but did not alter the affinities of naloxone and bremazocine. These results indicate the importance of Tyrl48 and His319 for the binding of fentanyl derivatives to the mu receptor. Functional studies using the mutant receptors will provide additional insight into the mechanism of action of RTI-4614-4 and its four enantiomers. 相似文献
85.
The intrathecal (i.t.) administration of the adenosine A1-receptor agonist R-phenylisopropyl-adenosine (R-PIA) reduced pain-related behaviors after peripheral nerve or spinal cord injury in rats. The endogenous ligand adenosine is clinically available and has been tested i.t. as an analgesic. Thus, we set out to investigate whether i.t. adenosine could reduce allodynia in a model of central pain in spinally injured rats. I.t. adenosine did not reduce mechanical and cold allodynia-like behaviors at doses of 10, 100 and 187 nmol, whereas i.t. R-PIA at 10 nmol markedly alleviated allodynia in the same animals. The lack of effect by exogenous adenosine may be due to pharmacokinetic or pharmacodynamic reasons. Alternatively, adenosine may have reduced affinity and selectivity towards the A1-receptors which may be important for the antiallodynic effect. 相似文献
86.
目的 探讨抑那通和缓退瘤联合治疗对正常前列腺,增生的前列腺(BPH)和前列腺癌以及睾丸的作用。方法 对16例接受联合内分泌治疗至少3个月且有治疗前后病理资料的前列腺癌患者的标本进行了系统的病理学检查。对内分泌治疗后的睾丸标本与同龄未接受治疗的进行对照研究。结果 14例内分泌治疗后的前列腺标本2例未见残存癌灶,9例对治疗有明显的反应;3例对治疗反应差,治疗并未降低前列腺癌的病理分期。3例内分泌治疗后 相似文献
87.
88.
在我国中等发达及上农村地区,大病统筹合作医疗或医疗保险以其可缓解农村居民的就医经济风险而受到欢迎,但是在方案的拟订过程中尚存在一些明显的技术缺陷,比如,“大病”的技术定义、农村居民就医经济风险分析、风险临界线界定、保险经付比测算和保险费率厘定等,这些技术的缺乏,已严重影响农村合作医疗或医疗保险的推广和实施效果。 相似文献
89.
90.
目的 观察氯地滴眼液对家兔眼压及房角组织影响。方法 用60只家兔设实验和对照组,以含0.175%氯霉素和0.15%地塞米松的氯地跟液滴眼,每日4次,生理盐水对照。于1/2、1、2、3月测眼压后处死家兔以电镜观察房角组织变化。结果 眼压和房角组织结构与对照组无明显差异。结论 临床应用氯地眼液3月内是安全的。 相似文献