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排序方式: 共有743条查询结果,搜索用时 15 毫秒
81.
Li-Jie Li Xiang-Min Zheng Dao-Zhen Jiang Wei Zhang Hong-Liang Shen Cheng-Xiang Shan Sheng Liu Ming Qiu -F Minimally Invasive Surgical Center Changzheng Hospital Second Military Medical University Shanghai China Author contributions: Li LJ Zheng XM Jiang DZ Zhang W Shen HL Liu S Shan CX Qiu M contribute to literature search Qiu M Li LJ Zheng XM wrote the review. 《World journal of gastroenterology : WJG》2010,16(19):2341-2347
The development of laparoscopic surgery has generated the new field of study, laparoscopic anatomy. This article reviews the reported literature on laparoscopic anatomy and explores how it has evolved along with advances in abdominal surgery. In addition, the principal concerns in current laparoscopic anatomy research are discussed, including: (1) types of special adjacent anatomical structures; and (2) special surgical planes and anatomical landmarks. Understanding of systematic laparoscopic anatomy can pr... 相似文献
82.
Ameet Sarpatwari Dimitri Bennett John W. Logie Amit Shukla Kathleen J. Beach Adrian C. Newland Simon Sanderson Drew Provan 《Haematologica》2010,95(7):1167-1175
Background
The risk of thromboembolic events in adults with primary immune thrombocytopenia has been little investigated despite findings of increased susceptibility in other thrombocytopenic autoimmune conditions. The objective of this study was to evaluate the risk of thromboembolic events among adult patients with and without primary immune thrombocytopenia in the UK General Practice Research Database.Design and Methods
Using the General Practice Research Database, 1,070 adults (≥18 years) with coded records for primary immune thrombocytopenia first referenced between January 1st 1992 and November 30th 2007, and having at least one year pre-diagnosis and three months post-diagnosis medical history were matched (1:4 ratio) with 4,280 primary immune thrombocytopenia disease free patients by age, gender, primary care practice, and pre-diagnosis observation time. The baseline prevalence and incidence rate of thromboembolic events were quantified, with comparative risk modelled by Cox’s proportional hazards regression.Results
Over a median 47.6 months of follow-up (range: 3.0–192.5 months), adjusted hazard ratios of 1.58 (95% CI, 1.01–2.48), 1.37 (95% CI, 0.94–2.00), and 1.41 (95% CI, 1.04–1.91) were found for venous, arterial, and combined (arterial and venous) thromboembolic events, respectively, when comparing the primary immune thrombocytopenia cohort with the primary immune thrombocytopenia disease free cohort. Further event categorization revealed an elevated incidence rate for each occurring venous thromboembolic subtype among the adult patients with primary immune thrombocytopenia.Conclusions
Patients with primary immune thrombocytopenia are at increased risk for venous thromboembolic events compared with patients without primary immune thrombocytopenia. 相似文献83.
MacPherson SE Della Sala S Logie RH Wilcock GK 《Cortex; a journal devoted to the study of the nervous system and behavior》2007,43(7):858-865
The current study examined the hypothesis that patients with Alzheimer's disease (AD) have a selective deficit in the coordination mechanism of the central executive, which is reflected in their inability to coordinate the performance of two tasks concurrently. One criticism of the previous studies in the literature is that they employ tasks that do not necessarily draw upon the separate peripheral mechanisms within working memory but combine a memory load with a perceptuomotor load. Therefore, the aim of the study was to examine the effects of AD and healthy adult ageing on a verbal memory plus visuospatial memory dual task paradigm. We investigated the performance of 15 AD patients and 20 healthy younger and 20 healthy older individuals on three different dual task combinations (i) digit recall and visual pattern recall; ii) digit recall and tracking; and iii) digit recall and articulatory suppression. The results demonstrate a significant dual task impairment in AD patients when two memory tasks are performed simultaneously compared to healthy younger and older adults. In contrast, there was not a significant age-related disruption in performance in healthy individuals compared to single task conditions. As the demands of each task were adjusted for individual ability levels, this provides further support for there being a specific AD dual task decrement in the mechanism responsible for coordinating dual task performance, which is separate from the resources needed to perform the tasks independently. 相似文献
84.
Older adults have difficulties in binding information in long-term memory (e.g. objects with colours). The effect of age on visual short-term memory (VSTM) binding is less well understood. Recent evidence has suggested that older adults' VSTM for colours bound to shapes or for locations bound in configural representations may be preserved. In two experiments we investigated whether this lack of an age effect on VSTM for bound features can be reproduced when features are drawn from the same dimension (i.e. colour-colour binding) and when spatial clues are not available. Younger and older adults were presented with two sequential arrays of unicoloured or bicoloured objects and their accuracy in detecting changes between arrays was used as the measure of memory performance. Memory was assessed using a change detection paradigm for unicoloured objects and for bicoloured objects with changes in colour conjunctions (i.e. colours swapping between objects) or with changes in non-conjunctive colours (i.e. colours replacing colours in the study array). Both young and older adults were less accurate at remembering objects defined by colour conjunctions than unicoloured objects or objects composed of two non-conjunctive colours (Experiment 1). Increasing task demands in terms of memory and perceptual load had no greater effect on the older than the younger adults (Experiment 2). We suggest (1) that colours were not integrated into single units in VSTM; (2) that remembering the binding between colours has a cost; and (3) that neither of these effects are age-dependent. 相似文献
85.
Oral Diseases (2010) 16 , 136–145 Objective: The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. Design: Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. Methods: The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. Results: Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. Conclusion: Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches. 相似文献
86.
A review of studies of parent-child communication about sexuality and HIV/AIDS in sub-Saharan Africa
Parent-child sexuality communication has been identified as a protective factor for adolescent sexual and reproductive health, including HIV infection. The available literature on this topic in sub-Saharan Africa is increasing; however a systematic review of studies has not been conducted. This article reviews the literature in the area of parental or caregiver and child communication about sexuality and HIV/AIDS in sub-Saharan Africa. A review of peer reviewed literature published between 1980 and April 2011 was conducted. Communication process studies investigating the frequency, content, style, tone of discussions, preferences, as well as associations with and barriers to sexuality communication are reviewed. In addition, studies which examine behavioral associations with parent-child sexuality communication, and intervention studies to improve parent-child sexuality communication are examined. The findings from process studies suggest wide variation in terms of frequency of discussions, with a range of socio-demographic and other factors associated with sexuality communication. Overall, findings demonstrate that discussions tend to be authoritarian and uni-directional, characterized by vague warnings rather than direct, open discussion. Moreover, parents and young people report a number of barriers to open dialogue, including lack of knowledge and skills, as well as cultural norms and taboos. Findings are less clear when it comes to associations between parental communication and adolescent sexual activity and contraception use. However, nascent indications from intervention research suggest positive findings with increases in frequency and comfort of discussions, among other outcomes. Gaps in the research are identified and discussed with implications for future studies. 相似文献
87.
Adam Z.J. Zeman Lorna A. Torrens David J. McGonigle Robert H. Logie 《Neuropsychologia》2010,48(1):145-155
The capacity for imagery, enabling us to visualise absent items and events, is a ubiquitous feature of our experience. This paper describes the case of a patient, MX, who abruptly lost the ability to generate visual images. He rated himself as experiencing almost no imagery on standard questionnaires, yet performed normally on standard tests of perception, visual imagery and visual memory. These unexpected findings were explored using functional MRI scanning (fMRI). Activation patterns while viewing famous faces were not significantly different between MX and controls, including expected activity in the fusiform gyrus. However, during attempted imagery, activation in MX's brain was significantly reduced in a network of posterior regions while activity in frontal regions was increased compared to controls. These findings are interpreted as suggesting that MX adopted a different cognitive strategy from controls when performing the imagery task. Evidence from experimental tasks thought to rely on mental imagery, such as the Brooks’ matrices and mental rotation, support this interpretation. Taken together, these results indicate that successful performance in visual imagery and visual memory tasks can be dissociated from the phenomenal experience of visual imagery. 相似文献
88.
89.
抗病毒药物2,5,6-三取代-4(3H)嘧啶酮衍生物的合成及诱导干扰素活性 总被引:2,自引:0,他引:2
In order to search for more ideal antiviral drugs,21 substituted pyriiT1idinone derivatives were designed and synthesized,among which 11 were not reported before. The cheinicalstructures were characterized by elemen tal and spectral analysis. The serum interferon - inducing activity was tested in mice. All 2-amino-5-bromo-6-substituted-4-(3H)pyrimidinone compounds were shown to have interferon inducing activity.The corresponding substituted pyrimidine thiones were less active.The new compounds of 6-sulfophenyl derivatives are soluble in、water, but the interferon-inducing activity are not higher than the original compound of ABPP. 相似文献
90.
抗病毒药物2,5,6-三取代-4(3H)嘧啶酮衍生物的合成及诱导干扰素活性刘新泳,徐丽君(山东医科大学药学系济南250012)取代嘧啶酮类化合物是一类小分干扰素诱导剂,有抗病毒、抗肿瘤、杀菌抑霉、诱导干扰素和白介素、免疫调节等多种生物活性(1)。目前?.. 相似文献