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101.
Maryann D'Alessandro George Vachtsevanos Rosana Esteller Javier Echauz Stephen Cranstoun Greg Worrell Landi Parish Brian Litt 《Clinical neurophysiology》2005,116(3):506-516
OBJECTIVE: To develop a prospective method for optimizing seizure prediction, given an array of implanted electrodes and a set of candidate quantitative features computed at each contact location. METHODS: The method employs a genetic-based selection process, and then tunes a probabilistic neural network classifier to predict seizures within a 10 min prediction horizon. Initial seizure and interictal data were used for training, and the remaining IEEG data were used for testing. The method continues to train and learn over time. RESULTS: Validation of these results over two workshop patients demonstrated a sensitivity of 100%, and 1.1 false positives per hour for Patient E, using a 2.4s block predictor, and a failure of the method on Patient B. CONCLUSIONS: This study demonstrates a prospective, exploratory implementation of a seizure prediction method designed to adapt to individual patients with a wide variety of pre-ictal patterns, implanted electrodes and seizure types. Its current performance is limited likely by the small number of input channels and quantitative features employed in this study, and segmentation of the data set into training and testing sets rather than using all continuous data available. SIGNIFICANCE: This technique theoretically has the potential to address the challenge presented by the heterogeneity of EEG patterns seen in medication-resistant epilepsy. A more comprehensive implementation utilizing all electrode sites, a broader feature library, and automated multi-feature fusion will be required to fully judge the method's potential for predicting seizures. 相似文献
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103.
Abdolamir Landi Mohammad Tayfeh Aligodarzi Ali Khodadadi Lorne A. Babiuk Sylvia van Drunen Littel‐van den Hurk 《Immunology》2018,153(4):532-544
The concept of dendritic cell (DC) maturation generally refers to the changes in morphology and function of DCs. Conventionally, DC maturity is based on three criteria: loss of endocytic ability, gain of high‐level capacity to present antigens and induce proliferation of T cells, and mobility of DCs toward high concentrations of CCL19. Impairment of DC maturation has been suggested as the main reason for infectivity or chronicity of several infectious agents. In the case of hepatitis C virus, this has been a matter of controversy for the last two decades. However, insufficient attention has been paid to the method of ex vivo maturation as the possible source of such controversies. We previously reported striking differences between DCs matured with different methods, so we propose the use of a standard quantitative index to determine the level of maturity in DCs as an approach to compare results from different studies. We designed and formulated a mathematically calculated index to numerically define the level of maturity based on experimental data from ex vivo assays. This introduces a standard maturation index (SMI) and weighted maturation index (WMI) based on strictly standardized mean differences between different methods of generating mature DCs. By calculating an SMI and a WMI, numerical values were assigned to the level of maturity achieved by DCs matured with different methods. SMI and WMI could be used as a standard tool to compare diversely generated mature DCs and so better interpret outcomes of ex vivo and in vivo studies with mature DCs. 相似文献
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B Landi M Tkoub M Gaudric R Guimbaud J Cervoni S Chaussade D Couturier J Barbier C Cellier 《Gut》1998,42(3):421-425
Background—Push-type enteroscopy, a recent methodfor investigating the small intestine, is currently undergoingassessment. Its diagnostic yield varies in the studies reported to date.
Aim—To assess the diagnostic value of push-typeenteroscopy according to indication.
Patients and methods—From January 1994 toSeptember 1995, 152 consecutive patients (mean age 34 years) underwentpush-type enteroscopy (jejunoscopy, n=93; retrograde ileoscopy, n=17;and double way enteroscopy, n=42). The indications were: unexplained iron deficiency anaemia or macroscopic gastrointestinal bleeding (n=76), radiological abnormalities of the small intestine (n=23), chronic diarrhoea and/or malabsorption syndrome (n=18), abdominal pain(n=12), and miscellaneous (n=23). All patients had undergone previousnegative aetiological investigations.
Results—The jejunum and ileum were exploredthrough 120 cm (30-160 cm) and 60 cm (20-120 cm). Digestivebleeding: lesions of the small bowel were found in 6% of the patientswith isolated iron deficiency anaemia and 20% of patients with patentdigestive haemorrhage. Radiological abnormalities of the smallintestine: push-type enteroscopy provided a diagnosis or modified theinterpretation of radiological findings in 18/23 cases (78%). Chronicdiarrhoea and/or malabsorption: push-type enteroscopy yieldedexplanatory findings in four cases (22%). Abdominal pain: push-typeenteroscopy provided no diagnosis.
Conclusion—In this series, push-type enteroscopywas of particular value in investigating patients with radiologicalabnormalities of the small intestine. It was of some value in theexploration of patent digestive haemorrhage or chronic diarrhoea, butnot of abdominal pain. Its value was limited in the exploration of irondeficiency anaemia.
Aim—To assess the diagnostic value of push-typeenteroscopy according to indication.
Patients and methods—From January 1994 toSeptember 1995, 152 consecutive patients (mean age 34 years) underwentpush-type enteroscopy (jejunoscopy, n=93; retrograde ileoscopy, n=17;and double way enteroscopy, n=42). The indications were: unexplained iron deficiency anaemia or macroscopic gastrointestinal bleeding (n=76), radiological abnormalities of the small intestine (n=23), chronic diarrhoea and/or malabsorption syndrome (n=18), abdominal pain(n=12), and miscellaneous (n=23). All patients had undergone previousnegative aetiological investigations.
Results—The jejunum and ileum were exploredthrough 120 cm (30-160 cm) and 60 cm (20-120 cm). Digestivebleeding: lesions of the small bowel were found in 6% of the patientswith isolated iron deficiency anaemia and 20% of patients with patentdigestive haemorrhage. Radiological abnormalities of the smallintestine: push-type enteroscopy provided a diagnosis or modified theinterpretation of radiological findings in 18/23 cases (78%). Chronicdiarrhoea and/or malabsorption: push-type enteroscopy yieldedexplanatory findings in four cases (22%). Abdominal pain: push-typeenteroscopy provided no diagnosis.
Conclusion—In this series, push-type enteroscopywas of particular value in investigating patients with radiologicalabnormalities of the small intestine. It was of some value in theexploration of patent digestive haemorrhage or chronic diarrhoea, butnot of abdominal pain. Its value was limited in the exploration of irondeficiency anaemia.
Keywords:enteroscopy; gastrointestinal bleeding
相似文献106.
Nicola de’Angelis Filippo Landi Maria Clotilde Carra Daniel Azoulay 《World journal of gastroenterology : WJG》2015,21(39):11185-11198
AIM: To investigate the efficacy(survival) and safety of treatments for recurrent hepatocellular carcinoma(HCC) in liver transplantation(LT) patients.METHODS: Literature search was performed on available online databases without a time limit until January 2015. Clinical studies describing survival after HCC recurrence in LT patients were retrieved for a fulltext evaluation. A total of 61 studies were selected: 13 case reports, 41 retrospective case series, and 7 retrospective comparative studies.RESULTS: Based on all included studies, the mean HCC recurrence rate was 16% of all LTs for HCC. A total of 1021 LT patients experienced HCC recurrence. The median time from LT to HCC recurrence was 13 mo(range 2-132 mo). The majority of patients(67%) presented with HCC extra-hepatic recurrences, involving lung, bone, adrenal gland, peritoneal lymph nodes, and rarely the brain. Overall survival after HCC recurrence was 12.97 mo. Surgical resection of localized HCC recurrence and Sorafenib for controlling systemic spread of HCC recurrence were associated with the higher survival rates(42 and 18 mo, res-pectively). However, Sorafenib, especially when combined with m TOR, was frequently associated with severe side effects that required dose reduction or discontinuation CONCLUSION: Management of recurrent HCC in LT patients is challenging and associated with poor prognosis independently of the type of treatment. 相似文献
107.
E Tagliabue M C Fargnoli S Gandini P Maisonneuve F Liu M Kayser T Nijsten J Han R Kumar N A Gruis L Ferrucci W Branicki T Dwyer L Blizzard P Helsing P Autier J C García-Borrón P A Kanetsky M T Landi J Little J Newton-Bishop F Sera S Raimondi 《British journal of cancer》2015,113(2):354-363
Background:
The melanocortin-1-receptor (MC1R) gene regulates human pigmentation and is highly polymorphic in populations of European origins. The aims of this study were to evaluate the association between MC1R variants and the risk of non-melanoma skin cancer (NMSC), and to investigate whether risk estimates differed by phenotypic characteristics.Methods:
Data on 3527 NMSC cases and 9391 controls were gathered through the M-SKIP Project, an international pooled-analysis on MC1R, skin cancer and phenotypic characteristics. We calculated summary odds ratios (SOR) with random-effect models, and performed stratified analyses.Results:
Subjects carrying at least one MC1R variant had an increased risk of NMSC overall, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC): SOR (95%CI) were 1.48 (1.24–1.76), 1.39 (1.15–1.69) and 1.61 (1.35–1.91), respectively. All of the investigated variants showed positive associations with NMSC, with consistent significant results obtained for V60L, D84E, V92M, R151C, R160W, R163Q and D294H: SOR (95%CI) ranged from 1.42 (1.19–1.70) for V60L to 2.66 (1.06–6.65) for D84E variant. In stratified analysis, there was no consistent pattern of association between MC1R and NMSC by skin type, but we consistently observed higher SORs for subjects without red hair.Conclusions:
Our pooled-analysis highlighted a role of MC1R variants in NMSC development and suggested an effect modification by red hair colour phenotype. 相似文献108.
109.
110.
Natali A Vichi S Landi P Toschi E Severi S L'abbate A Ferrannini E 《Journal of internal medicine》2000,247(2):219-230
OBJECTIVES: To evaluate how the presence of arterial hypertension affects coronary atherosclerosis and prognosis in patients with, or at high risk of, ischaemic heart disease. DESIGN: Retrospective analysis of clinical records and follow-up data. SETTINGS: Single referral centre for ischaemic heart disease. SUBJECTS: All consecutive patients (n = 1700, 38% with hypertension) undergoing coronary angiography for the evaluation of ischaemic heart disease during 1983-92. RESULTS: On angiography, the likelihood of having three-vessel disease was higher amongst hypertensives (odds ratio = 1.41; 95% confidence interval [CI] = 1.08-1.85) after adjustment for age, sex, and angina symptoms. The sum of all visible stenoses (an index of overall atherosclerotic involvement) was 19% higher in hypertensives (262 +/- 204 vs. 220 +/- 194 units, P < 0.005). By multivariate analysis, the presence of hypertension made a modest (+ 28 units), albeit statistically significant, independent contribution to the total atherosclerosis score. On follow-up (median = 96 months), cardiovascular mortality was slightly higher in the hypertensive patients than in the normotensive group (P < 0.05 in a Kaplan-Meier analysis), but a proportional hazard analysis adjusting for age and gender showed no significant independent contribution of hypertension. Hypertensive patients, however, remained at higher risk of non-fatal myocardial infarction following discharge (adjusted odds ratio = 1.21, 95% CI = 1.03-1.46; P < 0.05). CONCLUSIONS: In this referral population, hypertension is a risk factor for presence of three-vessel disease. Distribution, severity and extension of coronary stenosis are similar to those of normotensive patients, and prognosis is only marginally affected. 相似文献