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991.
White-matter hyperintensities (WMHI) are frequently associated with cerebrovascular risk factors in the elderly, particularly hypertension, and have been interpreted as a subclinical form of ischemic brain damage. WMHI, clinical stroke and blood pressures show significant genetic influences. The objective of this study was to determine whether a relationship exists between family history of stroke and/or hypertension in first degree relatives and WMHI in the elderly. WMHI and stroke (CVA) volumes were quantified from brain MRI performed on 414 white, male twins born between 1917 and 1927 (average age 72.3 +/- 2.9 years). WMHI, adjusted for age and head size, was significantly correlated with the family history score (r = 0.21, p < 0.001). Dividing the family history scores into quintiles revealed significant differences in WMHI by quintile mean (p < 0.05). Subjects in the highest quintile of family history score had the highest mean WMHI. Recalculation of the family history score, by only counting relatives reported to have had a clinical stroke as a positive event, revealed a nonsignificant correlation with WMHI, but the correlation of the family history score with MRI CVA volume was significant (p < 0.05). Stepwise multivariate analysis including ApoE status, current smoking status, smoking packyear history, Doppler ankle/arm blood pressure ratios, current and long term hypertensive status and current systolic and diastolic pressures indicated that the stroke/hypertension family history score was the single best predictor (p < 0.01) of WMHI volumes. Family history was not an independent predictor of CVA volume.  相似文献   
992.
Exhaled nitric oxide (eNO) has been proposed as a potential indirect marker of lower airway inflammation in asthma. To investigate the existence of lower airways inflammation in allergic rhinitis eNO measurements were performed in 32 patients with symptomatic and asymptomatic seasonal allergic rhinitis early in and out of pollen seasons and in 80 healthy volunteers. To further define how exhaled NO is modified by therapy, NO levels were detected following 1-month treatment with either inhaled steroids or non-steroids therapy with nedocromil. Exhaled NO (mean +/- SE) was significantly elevated in patients with seasonal allergic rhinitis with and without symptoms (24.2 + 2.5 and 13.9 + 2.9 ppb, respectively) as compared to healthy volunteers (4.5 + 0.3 ppb) both in and out of pollen season (21.2 + 2.1 and 9.0 + 1.4 p.p.b., respectively) with a higher increase during the allergen exposure in season. Higher levels of exhaled NO were detected in patients with symptoms, either from the upper or lower airways, and with bronchial hyperreactivity. The increased exhaled NO in symptomatic patients was reduced only by inhaled steroids and not by nedocromil. These findings possibly suggest the existence of lower airway inflammation in both symptomatic and asymptomatic patients with seasonal allergic rhinitis in and out of pollen season. Thus, exhaled NO may be used as a non-invasive index for early detection of lower airway inflammation and for monitoring the optional treatment in patients with seasonal allergic rhinitis.  相似文献   
993.
The present study evaluated self-reported subjective complaints (29 single items and 11 scales) at precessation, on quit day, and on Days 1, 2, 3, 7, 14, 21, and 28 after cessation in 46 healthy quitters who remained abstinent for the first month after cessation (biochemically confirmed). Also tested on the same schedule were 29 nonsmokers matched for age and gender. Specific criteria were set for transient and offset effects based on the direction, magnitude, and time course of changes in symptoms after cessation. Results indicated that single-item anger, anxiety, depression, difficulty concentrating, irritability, restlessness, dizziness, and nausea, and the Shiffman-Jarvik Stimulation/Sedation Subscale, the Perceived Stress scale, and the POMS anger, confusion, and tension subscales met the criteria for transient effects, and that single-item desire to smoke, cough, and headache, and the Shiffman-Jarvik Psychological Subscale met the criteria for offset effects. These findings help to clarify which subjective complaints after smoking cessation are transient effects and which are offset effects, a distinction with important implications for understanding nicotine dependence and for designing pharmacological and nonpharmacological interventions for smoking cessation.  相似文献   
994.
感染模型家兔体内莫西沙星的药动学   总被引:5,自引:0,他引:5  
目的研究莫西沙星在感染家兔模型中的药物动力学。方法8只家兔经埴入高尔夫练习球并用肺炎链球菌感染3d后,用多剂量口服莫西沙星治疗,第5天进行药动学试验。用高效液相色谱法测定血药浓度。结果莫西沙星在家兔体内属线性药物并符合二房室模型;达峰时间为(1.2±0.6)h,峰浓度为(13.2±4.0)μg.ml  相似文献   
995.
OBJECTIVES: This study re-evaluates the awareness and attitudes of medical students concerning military programs, which can provide financial support for medical student education. An original study, 10 years ago, demonstrated a minimal awareness of these programs. With medical school tuitions rising dramatically in the intervening years, as well as the resultant student indebtedness increasing significantly, it is appropriate to readdress this knowledge of attitude toward financial options through military programs for medical students. Reassessment was undertaken using the same evaluation instrument. In the decade in which these four assessments were made, attitudes toward amelioration of medical student tuitional indebtedness, through programs sponsored by the Department of Defense, have worsened. This phenomenon jeopardizes military medicine and, in so doing, negatively impacts readiness of our Armed Forces.  相似文献   
996.
IntroductionThe use of multiparametric magnetic resonance imaging (MRI) with targeted biopsies of the prostate improves the diagnosis of clinically significant prostate cancer. Recent studies have shown that targeted prostate biopsies also more accurately predict final histopathology after radical prostatectomy (RP). There are three broad techniques for performing MRI-targeted prostate biopsy: cognitive MRI/ultrasound (US) fusion, software MRI/US fusion, and in-bore MRI-guided. Current practices recommend that a standard systematic 12-core prostate biopsy be performed, as well as targeted biopsies in patients with positive MRI findings. This study aimed to evaluate the accuracy of histological grading of cognitive MRI/US fusion prostate biopsy by comparing the histology from the targeted biopsy specimens (TB), standard systematic specimens (SB), and the combination of both (CB) specimens with the final histological grade from subsequent prostatectomy.MethodsA retrospective, single-center review of 115 patients who underwent standard systematic and cognitive MRI/US-targeted biopsy of the prostate before undergoing a RP between 2016 and 2019 was performed. MRI findings, biopsy, final histology International Society of Urological Pathology (ISUP) grades, and patient demographics were collected. Cochran’s Q test and McNemar test were used to compare the differences in upgrading, downgrading, and concordance between each biopsy group.ResultsThe concordance between SB, TB, and CB biopsy were 28.7%, 49.6%, and 50.4%, respectively. There was no significant difference in concordance between TB and CB. Patients were more likely to be downgraded on the final histology when comparing CB with TB alone (26.1% vs. 16.5%, p<0.05). In cases where an ISUP grade 1 cancer was diagnosed on TB (n=24), there was a 62.5% chance that the final histology would be upgraded. In the same sample, when combined with a SB, the risk of upgrading on final histology was reduced to 37.5%.ConclusionsAlthough grading concordance between TB and CB were similar, the concomitant use of a SB significantly reduced the rate of upgrading in the final RP histopathology. CB may result in better decision-making regarding treatment options and also have implications for intraoperative planning.  相似文献   
997.
998.
OBJECTIVE—To study and compare the effects of mental and physical stress on long QT syndrome (LQTS) patients.
DESIGN—Case-control study.
MAIN OUTCOME MEASURES—QT intervals were measured from lead V3. Serum potassium and plasma catecholamine concentrations were also monitored.
PATIENTS—16 patients with type 1 LQTS (LQT1), 14 with type 2 LQTS (LQT2), both groups asymptomatic, and 14 healthy control subjects.
INTERVENTIONS—Three types of mental stress tests and a submaximal exercise stress test.
RESULTS—Heart rate responses to mental stress and exercise were similar in all groups. During mental stress, the mean QT interval shortened to a similar extent in controls (-29 ms), LQT1 patients (-34 ms), and LQT2 patients (-30 ms). During exercise, the corresponding QT adaptation to exercise stress was more pronounced (p < 0.01) in healthy controls (-47 ms) than in LQT1 (-38 ms) or LQT2 patients (-38 ms). During exercise changes in serum potassium concentrations were correlated to changes in QT intervals in controls, but not in LQTS patients. LQT1 and LQT2 patients did not differ in serum potassium, catecholamine or heart rate responses to mental or physical stress.
CONCLUSIONS—QT adaptation to mental and exercise stress in healthy people and in patients with LQTS is different. In healthy people QT adaptation is more sensitive to physical than to mental stress while no such diverging pattern was seen in asymptomatic LQTS patients.


Keywords: exercise; long QT syndrome; mental stress; potassium channel  相似文献   
999.
高血压脑出血血肿周围组织血-脑屏障变化的动态观察   总被引:18,自引:0,他引:18  
目的动态观察高血压脑出血血肿周围组织血-脑屏障的变化.方法对6例高血压脑出血患者实施立体定向血肿碎吸术,术中取血肿周围少许脑组织进行超微病理观察.结果血-脑屏障的损伤与出血时间的长短呈正比.脑出血后24h,可见星形胶质细胞肿胀,部分细胞崩解、坏死.毛细血管周围细胞足突肿胀,血-脑屏障损坏.72h,部分星形胶质细胞高度肿胀,细胞器溶解.毛细血管内皮细胞胞核增大,胞质突入管腔,内皮细胞间紧密连接消失.4~7d,星形细胞高度肿胀,胞质内充满水肿液,细胞器消失,细胞变性.毛细血管星形细胞足突明显肿胀,血管周围可见微小出血灶.结论血-脑屏障的变化与患者的预后有密切关系.  相似文献   
1000.
Gastric xanthomas   总被引:2,自引:0,他引:2  
  相似文献   
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