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991.
Differences in exposure and biological markers of fluoride among White and African American children
Esperanza A. Martinez‐Mier DDS MSD PhD Armando E. Soto‐Rojas DDS MPH 《Journal of public health dentistry》2010,70(3):234-240
Objective: To determine differences in self‐reported fluoride exposure and fluoride exposure biomarkers between two racial groups. Methods: Questionnaires regarding fluoride exposure, urine and water collection kits were distributed to African American and White 7‐14‐year‐old children. Children received a dental exam for fluorosis. Water, urine, and saliva were analyzed for fluoride content. Questionnaire responses and results of sample analyses were compared and observed differences were analyzed. Results: 83 African American and 109 White children completed the study. Dental fluorosis was observed in 62.5 percent White and 80.1 percent African American children. Significant differences were found for fluorosis prevalence and severity between the groups (P < 0.05). Less African American children reported having used fluoride supplements in the past. White children began brushing their teeth at an earlier age. More White children visited a dentist for the first time before age 3. African American children reported currently using larger amounts of toothpaste. More Whites than African Americans had received topical fluoride treatments over the previous year. All of these differences were significant. Multivariate models showed that supplement use and amount of toothpaste used for brushing had significant associations to a child's fluorosis scores. Fluoride concentration of water and saliva was not different for the two groups; however, the fluoride content in urine was significantly higher in African Americans than in Whites [P < 0.05; 1.40 ± standard deviation (SD) 0.65 ppm versus 1.08 ± SD 0.28 ppm]. Conclusions: Differences in fluoride exposure between two racial groups were observed. These differences are complex and need to be better defined. 相似文献
992.
Federico Lussana Francesco Dentali Rosanna Abbate Ernesto d'Aloja Armando D'Angelo Valerio De Stefano Elena M. Faioni Elvira Grandone Cristina Legnani Ida Martinelli Paolo Simioni Daniela Tormene 《Thrombosis research》2009,124(5):e19-e25
The term thrombophilia describes an increased tendency to develop thrombosis and many laboratory markers with different strengths of association with thrombosis have been identified. The main causes of maternal mortality and morbidity in developed countries is venous thromboembolism (VTE) and obstetric complications. During pregnancy and puerperium the risk for VTE increases due to hemostatic imbalance towards a prothrombotic state, and it is further increased in women carriers of thrombophilia; recent studies have also demonstrated an association between thrombophilia and obstetric complications. These complications are, therefore, considered potentially preventable with the prophylactic administration of anticoagulant drugs, although their efficacy is not proven by data from randomized controlled trials. After a systematic comprehensive literature review and using a rigorous methodology, the expert panel formulated recommendations regarding the usefulness of screening for thrombophilia in pregnancy to identify high-risk women and for the management of antithrombotic prophyalxis. When evidence is lacking, consensus-based recommendations are provided. 相似文献
993.
Armando Perez de Prado Carlos Cuellas Alejandro Diego Antonio de Miguel Beatriz Samaniego Norberto Alonso-Orcajo Raul Carbonell Cristina Pascual Felipe Fernandez-Vazquez Ramon G. Calabozo 《Thrombosis research》2009,124(6):678-682
Introduction
A wide variability in the response to clopidogrel and magnitude of post-treatment platelet reactivity has been described. However, this has been demonstrated by light transmittance aggregometry, a method too laborious for daily practice. Point-of-care devices may overcome this limitation, but little is known on the predictive value of such measurements. Our objective was to determine the relationship between platelet reactivity and the incidence of myocardial damage following percutaneous coronary intervention (PCI) in patients with Non-ST-segment Elevation Acute Coronary Syndrome (NSTEACS).Materials and Methods
This prospective study included 93 patients with NSTEACS and PCI. All patients received a loading dose of 300 mg of clopidogrel and 250 mg of aspirin. Myocardial damage was defined as any elevation above upper limit of normal or previous levels of troponin T, assessed every 6 h for at least 24 h following PCI. Platelet reactivity not related to clopidogrel (BASE reactivity), related to P2Y12 inhibition (P2Y12 reactivity) and inhibition of platelet aggregation (IPA) were assessed immediately pre-PCI with the VerifyNow® device.Results
Myocardial damage was detected in 60 patients (64.5%). Higher BASE reactivity was associated with myocardial damage (287.8 ± 62.6 vs. 260 ± 55.9 units, p = 0.043) while a trend was found for P2Y12 reactivity (173.4 ± 70.3 vs. 149.2 ± 58.4 units, p = 0.109). No relationship was detected for IPA. Multivariate logistic regression analysis confirmed that BASE reactivity (p = 0.04) and P2Y12 reactivity (p = 0.03) were independent predictors of myocardial damage.Conclusions
Platelet reactivity before PCI appears to be better predictor of myocardial damage than does response to clopidogrel. 相似文献994.
Iaccarino C Tedeschi E Rapanà A Massarelli I Belfiore G Quarantelli M Bellotti A 《Journal of neurosurgery》2009,110(5):852-857
Object The aim of this study was to correlate intraoperative endoscopic third ventriculostomy (ETV) findings in hydrocephalic patients with the MR imaging appearance of the mammillary bodies (MBs), the fundamental anatomical landmarks of the third ventricle floor (TVF) region. Methods The authors reviewed brain MR images and intraoperative ETV records in 23 patients with hydrocephalus as well as MR imaging data from 120 randomized control volunteers of various ages to define the normal intermammillary distance (IMD). Results In control volunteers, no measurable IMD ("kissing" configuration) was observed in 91 (85%) of 107 cases, and there was mild MB splitting (mean +/- standard deviation, 0.18 +/- 0.12 cm) in only 16 cases with age-related cerebral atrophy. Among the 21 patients with complete MR imaging and ETV data sets, 12 ETV procedures were hindered by anatomical anomalies such as a thickened TVF or an "upward ballooning" phenomenon. On preoperative MR imaging in these 12 patients, there was an increased IMD (0.55 +/- 0.41 cm) compared with that in the remaining 9 patients (0.27 +/- 0.25 cm) who had a normal thin TVF during ETV and in the control group (0.03 +/- 0.08 cm). Magnetic resonance imaging and ETV data concordantly displayed nonsplit MBs in 6 of 9 cases with a thin TVF and split MBs in 10 of 12 cases with a thick TVF. Conclusions The normal configuration of MBs is no measurable IMD, with mild splitting occurring in patients with age-related brain atrophy. In hydrocephalic patients, a thickened TVF was present almost exclusively with an increased IMD on preoperative MR imaging and separated MBs on endoscopic viewing. Large retrospective series are needed to confirm that a preoperative increased IMD is predictive of a thickened TVF during ETV. 相似文献
995.
996.
The dream as a model for psychosis: an experimental approach using bizarreness as a cognitive marker 总被引:1,自引:0,他引:1
Scarone S Manzone ML Gambini O Kantzas I Limosani I D'Agostino A Hobson JA 《Schizophrenia bulletin》2008,34(3):515-522
Many previous observers have reported some qualitative similarities between the normal mental state of dreaming and the abnormal mental state of psychosis. Recent psychological, tomographic, electrophysiological, and neurochemical data appear to confirm the functional similarities between these 2 states. In this study, the hypothesis of the dreaming brain as a neurobiological model for psychosis was tested by focusing on cognitive bizarreness, a distinctive property of the dreaming mental state defined by discontinuities and incongruities in the dream plot, thoughts, and feelings. Cognitive bizarreness was measured in written reports of dreams and in verbal reports of waking fantasies in 30 schizophrenics and 30 normal controls. Seven pictures of the Thematic Apperception Test (TAT) were administered as a stimulus to elicit waking fantasies, and all participating subjects were asked to record their dreams upon awakening. A total of 420 waking fantasies plus 244 dream reports were collected to quantify the bizarreness features in the dream and waking state of both subject groups. Two-way analysis of covariance for repeated measures showed that cognitive bizarreness was significantly lower in the TAT stories of normal subjects than in those of schizophrenics and in the dream reports of both groups. The differences between the 2 groups indicated that, under experimental conditions, the waking cognition of schizophrenic subjects shares a common degree of formal cognitive bizarreness with the dream reports of both normal controls and schizophrenics. Though very preliminary, these results support the hypothesis that the dreaming brain could be a useful experimental model for psychosis. 相似文献
997.
Early-onset Alzheimer disease in an Italian family with presenilin-1 double mutation E318G and G394V
Batelli S Albani D Prato F Polito L Franceschi M Gavazzi A Forloni G 《Alzheimer disease and associated disorders》2008,22(2):184-187
The genetic form of Alzheimer disease (FAD) accounts for about 5% of total Alzheimer disease (AD) cases, and the discovery of FAD-linked genes has shed new light on AD pathogenic mechanism. The presenilins genes (PSEN-1 and PSEN-2) carry the large majority of FAD-linked mutations. Here, we report an Italian kindred with FAD and PSEN-1 double mutation E318G+G394V that clearly cosegregates with the pathology. The E318G mutation has not an assessed pathogenic function, but some data have highlighted a role as a risk factor for AD in a predisposed familiar background. The G394V mutation was still described in association to an AD case with reported (but not demonstrated) familiar cosegregation. In an attempt to better characterize the biochemical effect of this double mutation, we assessed A beta(1-40) and A beta(1-42) concentrations in conditioned media from primary skin fibroblasts obtained from AD-affected and healthy family members. We did not find any modification of the A beta(1-42)/A beta(1-40) ratio, suggesting that this double mutation might be involved in early-onset AD etiopathogenesis by affecting a PSEN-1 function other than gamma-secretase activity. 相似文献
998.
Leonardi E Devescovi V Perut F Ciapetti G Giunti A 《La Chirurgia degli Organi di Movimento》2008,92(2):97-103
Marrow stromal cells (MSC) are increasingly being introduced in orthopaedic practice as potentially powerful effectors of
bone regeneration. Since cell recovery of MSC is affected by a high degree of individual variability, sources for collecting
adequate amounts of safe and effective MSC under routine conditions are needed. We analysed if femoral bone marrow, which
is usually discarded during total hip arthroplasty procedures, is a reliable source of MSC to enhance bone healing and regeneration.
Mononuclear cells were isolated, assayed for typical MSC markers, harvested under appropriate culture conditions and evaluated
for their ability to differentiate into osteoblasts. Cell recovery and osteogenic potential were independent from donor gender
or age, suggesting that elderly individuals are eligible for autologous cell therapy. Although heterogeneous, the pool of
MSC recoveredfrom femoral marrow without further in vitro selection or manipulation proved highly effective in proliferating and differentiating along the osteogenic lineage. In conclusion,
this source of MSC offers a valuable tool to be used to promote osteogenesis and implant fixation. 相似文献
999.
1000.