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排序方式: 共有585条查询结果,搜索用时 15 毫秒
31.
32.
Giuseppe de Vito Lapo Turrini Caroline Müllenbroich Pietro Ricci Giuseppe Sancataldo Giacomo Mazzamuto Natascia Tiso Leonardo Sacconi Duccio Fanelli Ludovico Silvestri Francesco Vanzi Francesco Saverio Pavone 《Biomedical optics express》2022,13(3):1516
Light-sheet fluorescence microscopy (LSFM) enables real-time whole-brain functional imaging in zebrafish larvae. Conventional one-photon LSFM can however induce undesirable visual stimulation due to the use of visible excitation light. The use of two-photon (2P) excitation, employing near-infrared invisible light, provides unbiased investigation of neuronal circuit dynamics. However, due to the low efficiency of the 2P absorption process, the imaging speed of this technique is typically limited by the signal-to-noise-ratio. Here, we describe a 2P LSFM setup designed for non-invasive imaging that enables quintuplicating state-of-the-art volumetric acquisition rate of the larval zebrafish brain (5 Hz) while keeping low the laser intensity on the specimen. We applied our system to the study of pharmacologically-induced acute seizures, characterizing the spatial-temporal dynamics of pathological activity and describing for the first time the appearance of caudo-rostral ictal waves (CRIWs). 相似文献
33.
Test‐retest reliability of the default mode network in a multi‐centric fMRI study of healthy elderly: Effects of data‐driven physiological noise correction techniques 下载免费PDF全文
Rocco Marchitelli Ludovico Minati Moira Marizzoni Beatriz Bosch David Bartrés‐Faz Bernhard W. Müller Jens Wiltfang Ute Fiedler Luca Roccatagliata Agnese Picco Flavio Nobili Oliver Blin Stephanie Bombois Renaud Lopes Régis Bordet Julien Sein Jean‐Philippe Ranjeva Mira Didic Hélène Gros‐Dagnac Pierre Payoux Giada Zoccatelli Franco Alessandrini Alberto Beltramello Núria Bargalló Antonio Ferretti Massimo Caulo Marco Aiello Carlo Cavaliere Andrea Soricelli Lucilla Parnetti Roberto Tarducci Piero Floridi Magda Tsolaki Manos Constantinidis Antonios Drevelegas Paolo Maria Rossini Camillo Marra Peter Schönknecht Tilman Hensch Karl‐Titus Hoffmann Joost P. Kuijer Pieter Jelle Visser Frederik Barkhof Jorge Jovicich 《Human brain mapping》2016,37(6):2114-2132
Understanding how to reduce the influence of physiological noise in resting state fMRI data is important for the interpretation of functional brain connectivity. Limited data is currently available to assess the performance of physiological noise correction techniques, in particular when evaluating longitudinal changes in the default mode network (DMN) of healthy elderly participants. In this 3T harmonized multisite fMRI study, we investigated how different retrospective physiological noise correction (rPNC) methods influence the within‐site test‐retest reliability and the across‐site reproducibility consistency of DMN‐derived measurements across 13 MRI sites. Elderly participants were scanned twice at least a week apart (five participants per site). The rPNC methods were: none (NPC), Tissue‐based regression, PESTICA and FSL‐FIX. The DMN at the single subject level was robustly identified using ICA methods in all rPNC conditions. The methods significantly affected the mean z‐scores and, albeit less markedly, the cluster‐size in the DMN; in particular, FSL‐FIX tended to increase the DMN z‐scores compared to others. Within‐site test‐retest reliability was consistent across sites, with no differences across rPNC methods. The absolute percent errors were in the range of 5–11% for DMN z‐scores and cluster‐size reliability. DMN pattern overlap was in the range 60–65%. In particular, no rPNC method showed a significant reliability improvement relative to NPC. However, FSL‐FIX and Tissue‐based physiological correction methods showed both similar and significant improvements of reproducibility consistency across the consortium (ICC = 0.67) for the DMN z‐scores relative to NPC. Overall these findings support the use of rPNC methods like tissue‐based or FSL‐FIX to characterize multisite longitudinal changes of intrinsic functional connectivity. Hum Brain Mapp 37:2114–2132, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
34.
Coppola A Coppola L Luongo C Arciello A Cacciapuoti F Lama D Luongo M Ruggiero L Pastore A Gombos G 《The International journal of angiology》2007,16(1):7-11
Ozonized autohemotransfusion has been used as a complementary therapy in patients with peripheral arterial disease (PAD). To determine whether ozone therapy could acutely modify artery vasodilatory capacity, a flow-mediated dilation test was performed at the brachial artery level before and after an ozonized autohemotransfusion in 16 patients with PAD, mean (± SD) age 55±1.8 years, and 14 healthy volunteers matched for age, sex and body mass index. Before ozonized autohemotransfusion, the mean baseline diameter of the brachial artery was higher in PAD patients than in healthy subjects (4.6±0.54 mm versus 3.6±0.54 mm, P<0.001) while mean flow-mediated brachial artery dilation and percentage of increase in flow were significantly lower in PAD patients than in controls (6.3±6.1% versus 11.8±2.4%, P<0.02; 433±61% versus 580±46%, P<0.02, respectively). No significant changes were observed after ozonized autohemotransfusion, indicating that ozonized autohemotransfusion does not modify endothelium-dependent ischemia-induced vascular reactivity. 相似文献
35.
This review focuses on resting-state functional connectivity, a functional MRI technique which allows the study of spontaneous
brain activity generated under resting conditions. This approach is useful to explore the brain’s functional organization
and to examine if it is altered in neurological or psychiatric diseases. Resting-state functional connectivity has revealed
a number of networks which are consistently found in healthy subjects and represent specific patterns of synchronous activity.
In this review, we examine the behavioral, physiological and neurological evidences relevant to this coherent brain activity
and, in particular, to each network. The investigation of functional connectivity appears promising from a clinical perspective,
considering the amount of evidence regarding the importance of spontaneous activity and that resting-state paradigms are inherently
simple to implement. We also discuss some examples of existing clinical applications, such as in Alzheimer’s disease, and
emerging possibilities such as in pre-operative mapping and disorders of consciousness. 相似文献
36.
37.
Vesical dysfunctions after radical hysterectomy for cervical cancer: a critical review 总被引:13,自引:0,他引:13
Zullo MA Manci N Angioli R Muzii L Panici PB 《Critical reviews in oncology/hematology》2003,48(3):287-293
Functional disorders of the lower urinary tract are the most common long-term complications following radical surgery for cancer of the uterine cervix (8-80%). These disturbances were associated to the partial interruption of the autonomic fibers innervating the bladder during the resection of anterior, lateral and posterior parametrium and vaginal cuff. The pathophysiology of these changes is actually debated. The nature of the surgical damage appears to be a decentralization rather than a complete denervation and bladder dysfunctions may be either the unmasking of intrinsic detrusor activity, characterized by a loss of beta-adrenergic innervation and a consequent alfa-adrenergic hyperinnervation or the influence of remaining sympathetic innervation. No data on long-term bladder function in patients who underwent class 4 radical hysterectomy have been reported. In our experience on long-term vesical function in 38 patients with locally advanced cervical cancer treated with neoadjuvant chemotherapy and 4 Piver type radical hysterectomy, urinary symptoms were reported in 11 patients (29%), while a normal urodynamic finding was recorded in only nine patients (24%). The most common bladder dysfunction was the storage dysfunction (47%). The voiding dysfunction was present in one patient (3%) and stress urinary incontinence in 20 patients (53%). The parametrial and vaginal resections were compared among the urodynamic diagnosis The size of lateral parametria measured on the giant sections did not differ among the groups of urodynamic diagnosis, while the length of vagina removed was significantly longer in patients with detrusor dysfunctions (storage and voiding dysfunctions) than in patients with normal diagnosis or genuine stress incontinence. 相似文献
38.
Imad Sheiban M.D. Gianpaolo Trevi Dino Casarotto Alberto Marini Paolo Benussi Roberto Accardi Marcello Zanini Peppino Pugliese Luisa Bullian Graziano Montresor Stefano Ferrara Ludovico Antonio Scuro 《Cardiovascular and interventional radiology》1988,11(1):14-17
An attempt was made to assess noninvasively the patency of aorto-coronary bypass grafts by two-dimensional echocardiography
(2-D echo) in 21 patients who underwent myocardial revascularization. Fifteen patients had one graft while the other six had
two grafts. All 21 patients underwent angiography 6–18 months after operation. A day before angiography a 2-D echo was performed
with the aim of visualizing the bypass grafts. In 18 patients with 23 grafts (13 with 1 graft and 5 with 2 grafts) it was
possible to visualize the tract of the graft, by 2-D echo; 16 were judged patent on 2-D echo and confirmed by selective angiography,
while 5 grafts were considered occluded both on 2-D echo and angiography. The other 2 grafts were considered to be occluded
on 2-D echo but angiographic control displayed their patency. In 3 patients 2-D echo failed to visualize grafts that were
patent angiographically. These data must be considered preliminary and need validation in a larger number of patients. However
it is reasonable to conclude that 2-D echo has a reliable capacity to predict graft patency. Such an application may be of
value in sequential control of patients with aorto-coronary bypass surgery, especially when combined with other clinical and/or
technical data. 相似文献
39.
Proton MR spectroscopy in quantitative in vivo determination of fat content in human liver steatosis
Renata Longo Piero Pollesello Claudio Ricci Flora Masutti Bjarne J. Kvam Luisa Bercich Lory S. Croce Piergiovanni Grigolato Sergio Paoletti Benedetto De Bernard Claudio Tiribelli Ludovico Dalla Palma 《Journal of magnetic resonance imaging : JMRI》1995,5(3):281-285
To demonstrate that the lipid volume fraction In liver steatosis can be accurately estimated with in vivo hydrogen-1 magnetic resonance (MR) spectroscopy, the authors developed a calibration procedure based on in vitro MR spectroscopy of lipid extracts from steatotlc liver specimens. The lipid volume fractions determined with the calibration procedure were compared with the results of histomorphometry and with calibrated computed tomographic (CT) data. The volume fraction of fat determined with MR spectroscopy was in good agreement with the CT results, whereas histomorphometry underestimated the amount of hepatic fat. The results indicate that determination of the fat volume fraction in steatotic liver can be achieved noninvasively with MR spectroscopy. 相似文献
40.
Knee axial deformities associated with medial or lateral compartment osteoarthritis can be reliably addressed with high tibial osteotomies. Different surgical techniques can be successfully used for achieving the correction. Whatever the technique used, accurate patient selection and precise surgical procedure are critical to the success of the operation. The authors believe that proximal tibial osteotomy is a valuable procedure to achieve pain relief and to restore knee function in selected patients. Localized knee osteoarthritis of the highly motivated, older, active patient can also be included in the extended indications of the high tibial osteotomy. 相似文献