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101.
Hartman TJ Taylor PR Alfthan G Fagerstrom R Virtamo J Mark SD Virtanen M Barrett MJ Albanes D 《Cancer causes & control : CCC》2002,13(10):923-928
Background: The objective of this investigation was to evaluate the association between toenail selenium concentration and lung cancer risk in male smokers. Methods: We conducted a nested case–control study within the Alpha–Tocopherol Beta–Carotene Cancer Prevention Study cohort. This substudy included 250 randomly selected incident lung cancer cases and 250 controls matched on age (up to ± 5 years), intervention group assignment, and date or randomization (±15 days). Odds ratios (ORs) and 95% confidence intervals (CIs) were determined using conditional logistic regression methods. Finland began fortification of argricultural fertilizers in the fall of 1984, increasing the dietary intake, plasma, and toenail selenium concentrations for the population. The present analyses were based on the calculated residual of toenail selenium after regressing it on date of randomization. The selenium residual and the interaction of the residual with date of randomization were included in models with smoking status and body mass index as covariates. Results: We observed a suggestion of a protective association for higher selenium status among men who entered the trial early (when the range of selenium values included very low levels). The OR for men with adjusted toenail selenium concentrations at the 75th percentile compared to those with the lowest selenium concentrations ranged between 0.20 (0.09–0.44) for men randomized earliest in the trail and 0.61 (0.27–1.41) for men randomized in the fifth year. Conclusions: These results suggest that low selenium status may be associated with increased risk for lung cancer. 相似文献
102.
Increased plasma levels of pro- and anti-inflammatory cytokines in patients with febrile seizures 总被引:10,自引:2,他引:8
PURPOSE: Pro- and antiinflammatory cytokines regulate the febrile response during infection. Febrile seizures (FSs) conversely are associated with rapid onset of high fever. Activation of the cytokine network has been shown in previous studies of FSs and cytokines. In this study, the association between cytokines and FSs was further investigated. METHODS: Interleukin-1beta (IL-1beta), interleukin-1 receptor antagonist (IL-1RA), interleukin-6 (IL-6), interleukin-10, and tumor necrosis factor-alpha plasma levels were measured with enzyme-linked immunosorbent assay in 55 children with FSs and in 20 age-matched febrile controls immediately on arrival at the hospital. Cerebrospinal fluid cytokine levels also were measured in 16 FS children. RESULTS: The plasma IL-1RA/IL-1beta ratio (mean, 2,133 vs. 119; median, 790 vs. 105; p < 0.0001) and plasma IL-6 (mean, 41.7 pg/ml vs. 16.1 pg/ml; median, 19.6 pg/ml vs. 10.5 pg/ml; p = 0.005) were significantly higher in FS patients compared with control children. Logistic regression analysis was used to find the most significant predisposing factors for FSs. In this analysis, the high plasma IL-1RA/IL-1beta ratio was the most significant factor connected to FSs (OR, 41.5; 95% CI, 4.9-352.8), but high plasma IL-6 also was significantly associated with FSs (OR, 5.3; 95% CI, 1.4-20.3). CONCLUSIONS: Present results support the hypothesis that the cytokine network is activated and could have a role in the pathogenesis of FS. 相似文献
103.
Mäkikallio TH Tapanainen JM Tulppo MP Huikuri HV 《Cardiac Electrophysiology Review》2002,6(3):250-255
Analysis of heart rate (HR) variability has become an important widely used method for assessingcardiac autonomic regulation. Conventionally, HR variability has been analyzed with time and frequency domainmethods. Analysis of HR dynamics by methods based on nonlinear systems theory has opened a novel approach forstudying the abnormalities in HR behavior. Recent studies have shown that these measures, particularly scalinganalysis methods of HR dynamics, are altered among various patients populations with cardiovascular diseases, andthey provide prognostic information. Altered long-term scaling properties of HR dynamics and more random short-termHR fluctuation has been observed, e.g., among patients with previous myocardial infarction, and these alterationshave been shown to be associated with increased mortality rate. A relatively large body of data indicate thataltered scaling properties of R-R intervals are physiologically deleterious. These findings support the notion thatsome nonlinear methods, such as scaling and complexity measures, give clinically valuable information for riskstratification among various patient populations. This article provides a review of our current knowledge of theusefulness of dynamical measures of HR fluctuation. 相似文献
104.
105.
Nea Malila Mikko J Virtanen Jarmo Virtamo Demetrius Albanes Eero Pukkala 《European journal of cancer prevention》2006,15(2):103-107
A total of 29,133 male smokers, aged 50-69 years, were recruited into the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study in 1984-1988. The nationwide Finnish Cancer Registry (FCR) recorded 5944 incident cases of cancer in this cohort through the end of 1999. Compared with the FCR data of the entire Finnish male population of same age the standardized incidence ratio (SIR) of total cancer in the ATBC cohort was 1.55 [95% confidence interval (CI) 1.51-1.59]. There was a significant excess of established smoking-related malignancies, such as lung cancer (SIR 2.45, 95% CI 2.35-2.56), and cancers of the tongue, mouth, pharynx, larynx, oesophagus, pancreas, stomach, liver, urinary bladder and kidney. In addition to these sites, cancers of the prostate and colon were slightly more common in the ATBC cohort than in the total Finnish male population (SIR 1.10, 95% CI 1.04-1.18 and SIR 1.14, 95% CI 1.00-1.30, respectively). In conclusion, the risk of many cancers was significantly higher in the ATBC Study cohort compared with the total Finnish male population of same age. In addition to the well known smoking-related cancers, cigarette smoking may increase slightly the risk of colon and prostate cancer, too. 相似文献
106.
Freja Ebeling Maija Baer Pirkko Hormila Greta Järventie Pirjo Koistinen Kalevi Kätkä Kalevi Oksanen Mikko Perkkiö Tapani Ruutu Esa Soppi Lea Veijola and Gunnar Myllylä 《Vox sanguinis》1995,69(2):91-94
The tolerability and kinetics of a solvent-detergent-treated 6% intravenous immunoglobulin (IVIG) preparation were studied in 15 hypogammaglobulinaemia patients during 3–4 regular substitution infusions of 9–18 g, the mean dose being 359 mg/kg. The infusions were well tolerated, and the trough serum IgG levels achieved were comparable to two commercial IVIG preparations. The stepwise increase of the infusion rate up to 5 mg/kg/min and the use of this IVIG as a 12% solution were possible without serious adverse events in all the 6 studied hypogammaglobulinaemia patients. This greatly reduced the time needed for the infusions. 相似文献
107.
S Mikko L Andersson 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(10):4259-4263
Major histocompatibility complex (MHC) genes encode cell surface proteins whose function is to bind and present intracellularly processed peptides to T lymphocytes of the immune system. Extensive MHC diversity has been documented in many species and is maintained by some form of balancing selection. We report here that both European and North American populations of moose (Alces alces) exhibit very low levels of genetic diversity at an expressed MHC class II DRB locus. The observed polymorphism was restricted to six amino acid substitutions, all in the peptide binding site, and four of these were shared between continents. The data imply that the moose have lost MHC diversity in a population bottleneck, prior to the divergence of the Old and New World subspecies. Sequence analysis of mtDNA showed that the two subspecies diverged at least 100,000 years ago. Thus, viable moose populations with very restricted MHC diversity have been maintained for a long period of time. Both positive selection for polymorphism and intraexonic recombination have contributed to the generation of MHC diversity after the putative bottleneck. 相似文献
108.
109.
Koivusalo A Pakarinen M Vanamo K Lindahl H Rintala RJ 《Journal of pediatric surgery》2005,40(9):1376-1381
Background and Aim
Long-term respiratory, gastrointestinal, and vertebral sequelae are common after repair of congenital diaphragmatic defects (CDDs). The aim of this study was to assess the effect of these sequelae on the health-related quality of life (HRQoL) of adult survivors after CDD repair.Materials and Methods
A questionnaire, including 36-Item Health Survey Form (SF-36), 36-item Gastrointestinal Quality of Life Index (GIQLI), 55-item Psychosocial Survey, 9-item survey for Respiratory Symptoms-Related Quality of Life Index, and a symptoms query, was sent to 94 adult survivors of CDD and to 400 healthy control subjects. One SD lower than the age-adjusted national average in the 36-Item Health Survey Form score for physical or mental health was considered as low HRQoL.Results
Sixty-nine patients with CDD (72%) and 162 (41%) control subjects returned the questionnaire. The initial presentation was critical in less than 10% of patients with CDD. Forty-five patients with diaphragmatic hernia had primary closure; in 1 patient with diaphragmatic hernia, a patch was used. Twenty-four patients had plication of diaphragmatic eventration. The incidence of gastroesophageal reflux (20% vs 2%), recurrent intestinal obstruction (7% vs 0%), and recurrent abdominal pain (12% vs 2%) was significantly higher in patients with CDD than in control subjects, whereas no difference in the incidence of respiratory, musculoskeletal, or other health problems not associated with CDD was found. Scores in GIQLI, Psychosocial Survey, and Respiratory Symptoms-Related Quality of Life Index did not differ between patients with CDD and control subjects. Health-related quality of life was low in 17 (25%) of 69 patients with CDD, which exceeded 1.5 times the expected value. There was no correlation between the type or severity of the primary defect and HRQoL at the time of the study.Conclusion
Most adults with repaired CDD have good or satisfactory HRQoL. Congenital diaphragmatic defect-associated symptoms with or without acquired diseases significantly impair HRQoL in one fourth of the patients. 相似文献110.
Naum A Laaksonen MS Tuunanen H Oikonen V Teräs M Kemppainen J Järvisalo MJ Nuutila P Knuuti J 《European journal of nuclear medicine and molecular imaging》2005,32(12):1378-1383
Purpose Patient motion during dynamic PET studies is a well-documented source of errors. The purpose of this study was to investigate the incidence of frame-to-frame motion in dynamic 15O-water myocardial perfusion PET studies, to test the efficacy of motion correction methods and to study whether implementation of motion correction would have an impact on the perfusion results.Methods We developed a motion detection procedure using external radioactive skin markers and frame-to-frame alignment. To evaluate motion, marker coordinates inside the field of view were determined in each frame for each study. The highest number of frames with identical spatial coordinates during the study were defined as non-moved. Movement was considered present if even one marker changed position, by one pixel/frame compared with reference, in one axis, and such frames were defined as moved. We tested manual, in-house-developed motion correction software and an automatic motion correction using a rigid body point model implemented in MIPAV (Medical Image Processing, Analysis and Visualisation) software. After motion correction, remaining motion was re-analysed. Myocardial blood flow (MBF) values were calculated for both non-corrected and motion-corrected datasets.Results At rest, patient motion was found in 18% of the frames, but during pharmacological stress the fraction increased to 45% and during physical exercise it rose to 80%. Both motion correction algorithms significantly decreased (p<0.006) the number of moved frames and the amplitude of motion (p<0.04). Motion correction significantly increased MBF results during bicycle exercise (p<0.02). At rest or during adenosine infusion, the motion correction had no significant effects on MBF values.Conclusion Significant motion is a common phenomenon in dynamic cardiac studies during adenosine infusion but especially during exercise. Applying motion correction for the data acquired during exercise clearly changed the MBF results, indicating that motion correction is required for these studies. 相似文献