全文获取类型
收费全文 | 7386篇 |
免费 | 578篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 69篇 |
妇产科学 | 65篇 |
基础医学 | 383篇 |
口腔科学 | 98篇 |
临床医学 | 482篇 |
内科学 | 723篇 |
皮肤病学 | 38篇 |
神经病学 | 627篇 |
特种医学 | 66篇 |
外科学 | 256篇 |
综合类 | 832篇 |
预防医学 | 3560篇 |
眼科学 | 32篇 |
药学 | 632篇 |
中国医学 | 57篇 |
肿瘤学 | 80篇 |
出版年
2024年 | 6篇 |
2023年 | 155篇 |
2022年 | 310篇 |
2021年 | 390篇 |
2020年 | 366篇 |
2019年 | 520篇 |
2018年 | 421篇 |
2017年 | 282篇 |
2016年 | 236篇 |
2015年 | 240篇 |
2014年 | 554篇 |
2013年 | 483篇 |
2012年 | 586篇 |
2011年 | 553篇 |
2010年 | 379篇 |
2009年 | 393篇 |
2008年 | 331篇 |
2007年 | 315篇 |
2006年 | 251篇 |
2005年 | 179篇 |
2004年 | 145篇 |
2003年 | 117篇 |
2002年 | 94篇 |
2001年 | 70篇 |
2000年 | 59篇 |
1999年 | 42篇 |
1998年 | 36篇 |
1997年 | 29篇 |
1996年 | 30篇 |
1995年 | 24篇 |
1994年 | 13篇 |
1993年 | 28篇 |
1992年 | 21篇 |
1991年 | 15篇 |
1990年 | 13篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1985年 | 31篇 |
1984年 | 31篇 |
1983年 | 29篇 |
1982年 | 30篇 |
1981年 | 27篇 |
1980年 | 20篇 |
1979年 | 26篇 |
1978年 | 22篇 |
1977年 | 25篇 |
1976年 | 18篇 |
1975年 | 12篇 |
1974年 | 20篇 |
1973年 | 14篇 |
排序方式: 共有8014条查询结果,搜索用时 31 毫秒
31.
对《2007年医院管理年活动方案》的认识与思考 总被引:7,自引:0,他引:7
针对新出台的2007年医院管理年活动方案,文章归纳了2007年管理年活动的主要内容和重点要求,并针对当前我国医院实际,紧密结合《医院管理评价指南(试行)》,从理念、质量、服务和管理4个方面着重分析了医院管理者应当关注的问题,以更好地贯彻落实管理年的有关精神和要求,科学制定出适合各级医院特点的更为具体和更具操作性的实施细则,促进我国公立医院管理水平不断提升。 相似文献
32.
B. Ferger D. Stahl K. Kuschinsky 《Naunyn-Schmiedeberg's archives of pharmacology》1996,353(5):545-551
It was previously shown that a moderate dose of cocaine (10 mg/kg i.p.) produces a pattern in the EEG power spectrum which indicates a preferential activation of dopamine D1-like receptors, namely a decrease of power in most of the frequency bands. In contrast, a large dose of cocaine (30 mg/kg i.p.) produces a decrease of power in most of the frequency bands as well, but a selective increase in the alpha-1 band, characteristic for an additional activation of dopamine D2-like receptors.In the present experiments, it was studied in rats, if in the course of sensitization, a shift from D1-like to additional D2-like receptor activation will occur or not. For this study, the animals were treated 10 times with cocaine (either 10 or 20 mg/kg) and, after a drug free interval of 4 days, tested with the same dose administered previously. Acute administration of 10 mg/kg of cocaine increased the Locomotor activity slightly and its effect tended to be enhanced after repeated administration. Twenty mg/kg cocaine increased the locomotor activity more than the 10 mg/kg dose and its effect was significantly enhanced after repeated treatment. In addition, it was shown that the dose of 10 mg/kg of cocaine which activates D1- but not D2-like receptors is sufficient to elicit conditioned place preference.Ten mg/kg of cocaine produced a decrease of power in most of the frequency bands and this effect was slightly more pronounced after repeated treatment. Twenty mg/kg of cocaine acutely also produced a decrease in power in most of the frequency bands, but did not decrease the power in the alpha-1 band, being just at the threshold of activating D2-like receptors as well. Repeated administration led to a significant increase in power in the alpha-1 band and a less pronounced one in the alpha-2 band. This observation demonstrates that sensitization to cocaine can be manifest in the EEG and that after a certain dosage, a shift from an activation of D1-like dopamine receptors to an additional activation of D2-like receptors becomes obvious. 相似文献
33.
Robert K. McNamara R. Duncan Kirkby Gregory E. dePape Ronald W. Skelton Michael E. Corcoran 《Hippocampus》1993,3(2):149-152
There is some controversy about the role of long-term potentiation (LTP) in spatial learning. The authors have found that triggering generalized kindled seizures with stimulation of the perforant path disrupts spatial learning in the Morris water maze but that kindling per se does not affect spatial learning. It is suggested that abnormal electrical activity induced by high-frequency stimulation of the perforant path may have been responsible for the disruption of spatial learning previously attributed to LTP saturation. 相似文献
34.
Takeda H Matsumura Y Kuwata S Nakano H Shanmai J Qiyan Z Yufen C Kusuoka H Matsuoka M 《International journal of medical informatics》2004,73(3):311-316
To enhance medical cooperation between the hospitals and clinics around Osaka local area, the healthcare network system, named Osaka Community Healthcare Information System (OCHIS), was established with support of a supplementary budget from the Japanese government in fiscal year 2002. Although the system has been based on healthcare public key infrastructure (PKI), there remain security issues to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority in contract with the Japanese Medical Information Systems Organization (MEDIS) in 2003. This paper describes the experimental design and the results of the study concerning message security. 相似文献
35.
Background
Since its sudden appearance and link to microcephaly in 2015, the number of PubMed references for Zika virus (ZIKV) has risen from 181 to 5163, at time of writing, with a vast proportion focused on the consequences of ZIKV infection during pregnancy. This level of attention underlies increased demand for sensitive and specific diagnostic tools able to assess risk to an unborn child, as well as to understand the dynamics and consequences of viral persistence.Aim
Review the expanding knowledge on ZIKV persistence and diagnostic challenges and summarize current advancements in detection.Sources
Peer-reviewed articles based on the search terms ‘Zika’ and ‘ZIKV’ combined with the terms ‘diagnostics’ ‘point-of-care diagnostics’ ‘viral load’ ‘persistence’ ‘detection’ ‘treatment’ ‘nucleic acid amplification testing’ ‘microsphere’ ‘PVRT’ ‘RVNT’ ‘RT-LAMP’ ‘NASBA’ SIBA’ ‘RPA’ ‘SHERLOCK’ ‘ELISA’, and ‘TMA’ as well as laboratory experience of the authors.Content
Topics covered include the emergence of the ZIKV epidemic, pathogenesis of ZIKV infection, the nature of ZIKV persistence, complications in serological diagnosis, tried and novel diagnostic laboratory techniques, and a recent accounting of point-of-care testing (POCT) methods.Implications
Surveillance and research in the case of ZIKV has shifted into a more rapid and coordinated worldwide directive than has occurred with most viral epidemics to date. The particular concentration of outbreaks in resource-limited settings increases the need for simple assays capable of reliable, inexpensive, high-throughput ZIKV diagnosis. This review serves to both catalogue current diagnostic options and consider their suitability at point-of-care. 相似文献36.
3,4-methylenedioxy-methylamphetamine (MDMA) (‘Ecstasy’) and its analogue 3,4-methylenedioxy-methylamphetamine (MDE) (‘Eve’) are well known illicit street drugs mainly abused by young people. In spite of the actual research going on, the classification of their abuse potential remains unclear. Since secondary reinforcers are the main factors responsible for craving and relapse, the aim of our study was to assess the potency of MDMA and MDE in a second order reinforcement paradigm, i.e. conditioned place preference (CPP). For the general assessment of our study conditions, we compared MDMA with amphetamine. Unexpectedly, no significant CPP for MDMA was found in contrast to amphetamine. Detailed analysis of current literature led us to the working hypothesis that social environment is crucial for the development of CPP. In a subsequent experiment we tested the influence of housing conditions on CPP using MDMA and demonstrated that isolated animals show significant CPP compared to group-housed ones. In order to better understand the rewarding mechanisms of Ecstasy-derivatives, we tested both the racemic drugs and the pure isomers in the CPP paradigm. Both MDMA's optical isomers and racemic MDMA showed significant CPP without notable differences, while MDE and its isomers completely failed to show any significant CPP. In conclusion, the mechanism by which MDMA induces addiction is much more complicated than assumed so far and more pronounced in isolated animals. The fact that both optical isomers of MDMA led to CPP implies that at least two pathways by which MDMA induces craving behaviour exist. 相似文献
37.
The existence of subgenomic RNAs is well established in the case of plant viruses such as tobacco mosaic virus (TMV). However, except for the subgenomic coat protein mRNA, it is not known whether the other subgenomic RNAs have a function in the life cycle of the virus. In search of more information about one of the major subgenomic RNAs-intermediate length RNA-2 or I2 RNA-of TMV, in vitro and in vivo translational studies were performed. The I2 RNA, which codes in vitro for the synthesis of a 30K (K = kilodalton) protein, appears to be uncapped as judged by the need of different in vitro translation conditions for the synthesis of this protein, compared to the conditions required for the synthesis of the 126K and 183K proteins coded by the capped genomic RNA. In vivo a protein migrating in the same position as the 30K protein synthesized in vitro can be detected in infected tobacco leaves. Since this protein occurs transiently early upon infection, whether it is virus-coded or virus-induced, it could have an early function during infection. 相似文献
38.
Social interactions have been shown to be rewarding for adolescent and adult rats; however, there has been little emphasis on comparing the strength of the rewarding value of social stimuli across ontogeny. Since age differences in social interactions may vary with sex or housing circumstances, the present study assessed social conditioned place preference (CPP) in adolescent and adult male and female Sprague-Dawley rats housed either socially or in isolation and conditioned with either group-housed or isolate-housed partners. Isolated animals of both sexes and ages demonstrated social CPP, with the strongest preference emerging in adolescent males. Social CPP was not evident in group-housed adults whereas group-housed adolescents developed a preference for the compartment previously paired with similarly housed partners; however, when socially housed adolescents were conditioned with isolated partners, social CPP did not emerge. Age differences in social CPP may reflect age-related neural alterations in brain systems implicated in regulation of social behavior. 相似文献
39.
Diagnosis of paracoccidioidomycosis in an immigrant who had returned to Italy following a long sojourn in Venezuela prompted a review of imported cases of this Latin American disease in nonendemic countries. Forty-two such instances of well documented paracoccidioidomycosis were compiled. Among these, eleven individuals had arrived in nonendemic countries with active symptomatic infections, fifteen others were first suspected of having tuberculosis, and four each were considered to have blastomycosis caused by Blastomyces dermatidis and carcinomas. Three, individuals were considered to have Wegner's granulomatosis or blastomycosis. Two other patients were treated for syphilis before being diagnosed as having paracocidioidomycosis. A striking feature of most of these cases was the long asymptomatic period following initial infection. The dormant periods ranged form four months to 60 years with an average duration of 14 years. The need to question patients about travel to or residency in foreign countries is emphasized, along with the necessity to include the mycoses in differential diagnoses. Three reported cases, all from Africa with no history of travel to the endemic areas of the New World, were considered to be doubtful. In one of these, Russell bodies apparently had been mistaken for the tissue-form cells of Paracoccidioides brasiliensis. A Japanese case, upon restudy of available histologic slides, revealed that the fungal cells present in various organs were those of Cryptococcus neoformans and not of P. brasiliensis.Corresponding author 相似文献
40.
Anatomical disassociation of amphetamine's rewarding and aversive effects: An intracranial microinjection study 总被引:2,自引:0,他引:2
Amphetamine has rewarding properties in some behavioral paradigms, such as self-administration and conditioned place preference (CPP), but an aversive component is also apparent when the drug is tested with the conditioned taste aversion (CTA) paradigm. The persent study was an attempt to determine the neuroanatomical substrates of the drug's rewarding and aversive effects. Previous evidence suggested that amphetamine's stimulation of activity in dopaminergic synapses is critical for both effects. Amphetamine was therefore micro-injected bilaterally (10 g/0.5 l per side) into six different dopaminergic sites, each in a different group of animals: the medial prefrontal cortex, nucleus accumbens, anteromedial caudate nucleus, lateroventral caudate nucleus, amygdala, and the region subjacent to the area postrema (AP region). The effects of these injections in both the taste and place conditioning paradigms were examined in separate experiments. Of the six sites, a significant CPP was observed only with accumbens injections and a significant CTA was observed only with AP region injections. It was concluded that the accumbens plays a primary role in mediating the rewarding effects of amphetamine and that the AP region plays a primary role in mediating the CTA. This constitutes an anatomical disassociation of amphetamine's rewarding and aversive effects. The differential associative bias of place-reward and taste-aversion learning apparent in the results is discussed.
Offprint requests to: N.M. White 相似文献