全文获取类型
收费全文 | 3667篇 |
免费 | 199篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 114篇 |
妇产科学 | 49篇 |
基础医学 | 545篇 |
口腔科学 | 21篇 |
临床医学 | 300篇 |
内科学 | 725篇 |
皮肤病学 | 79篇 |
神经病学 | 398篇 |
特种医学 | 130篇 |
外科学 | 475篇 |
综合类 | 12篇 |
一般理论 | 1篇 |
预防医学 | 332篇 |
眼科学 | 20篇 |
药学 | 335篇 |
中国医学 | 21篇 |
肿瘤学 | 281篇 |
出版年
2023年 | 21篇 |
2022年 | 28篇 |
2021年 | 64篇 |
2020年 | 34篇 |
2019年 | 49篇 |
2018年 | 92篇 |
2017年 | 51篇 |
2016年 | 67篇 |
2015年 | 64篇 |
2014年 | 96篇 |
2013年 | 112篇 |
2012年 | 242篇 |
2011年 | 249篇 |
2010年 | 169篇 |
2009年 | 126篇 |
2008年 | 219篇 |
2007年 | 229篇 |
2006年 | 224篇 |
2005年 | 244篇 |
2004年 | 226篇 |
2003年 | 196篇 |
2002年 | 187篇 |
2001年 | 93篇 |
2000年 | 81篇 |
1999年 | 98篇 |
1998年 | 50篇 |
1997年 | 39篇 |
1996年 | 38篇 |
1995年 | 33篇 |
1994年 | 30篇 |
1993年 | 20篇 |
1992年 | 47篇 |
1991年 | 36篇 |
1990年 | 43篇 |
1989年 | 26篇 |
1988年 | 31篇 |
1987年 | 19篇 |
1986年 | 20篇 |
1985年 | 18篇 |
1984年 | 11篇 |
1983年 | 17篇 |
1982年 | 11篇 |
1981年 | 11篇 |
1980年 | 15篇 |
1979年 | 17篇 |
1978年 | 7篇 |
1977年 | 9篇 |
1971年 | 5篇 |
1970年 | 4篇 |
1969年 | 4篇 |
排序方式: 共有3870条查询结果,搜索用时 15 毫秒
1.
A I D'hulst K R Bracke T Maes J L De Bleecker R A Pauwels G F Joos G G Brusselle 《The European respiratory journal》2006,28(1):102-112
Chronic obstructive pulmonary disease (COPD) is characterised by a local pulmonary inflammatory response to respiratory pollutants and by systemic inflammation. Tumour necrosis factor (TNF)-alpha has been implicated in systemic effects of COPD and operates by binding the p55 (R1) and p75 (R2) TNF-alpha receptors. To investigate the contribution of each TNF-alpha receptor in the pathogenesis of COPD, the present study examined the effects of chronic air or cigarette smoke (CS) exposure in TNF-alpha R1 knockout (KO) mice, TNF-alpha R2 KO mice and wild type (WT) mice. CS was found to significantly increase the protein levels of soluble TNF-alpha R1 (by four-fold) and TNF-alpha R2 (by 10-fold) in the bronchoalveolar lavage of WT mice. After 3 months, CS induced a prominent pulmonary inflammatory cell influx in WT and TNF-alpha R1 KO mice. In TNF-alpha R2 KO mice, CS-induced pulmonary inflammation was clearly attenuated. After 6 months, no emphysema was observed in CS-exposed TNF-alpha R2 KO mice in contrast to WT and TNF-alpha R1 KO mice. CS-exposed WT and TNF-alpha R1 KO mice failed to gain weight, whereas the body mass of TNF-alpha R2 KO mice was not affected. These current findings suggest that both tumour necrosis factor-alpha receptors contribute to the pathogenesis of chronic obstructive pulmonary disease, but tumour necrosis factor-alpha receptor-2 is the most active receptor in the development of inflammation, emphysema and systemic weight loss in this murine model of chronic obstructive pulmonary disease. 相似文献
2.
Marieke C Wichers Gunter Kenis Carsten Leue Ger Koek Geert Robaeys Michael Maes 《Neuropsychopharmacology》2006,60(1):77-79
BACKGROUND: Major depression has been associated cross-sectionally with increased cell-mediated immune activation but causality has been difficult to establish. This study prospectively investigated the hypothesis that baseline level of immune activation predicts the development of depression during interferon-alpha (IFN-alpha) treatment. METHODS: Sixteen hepatitis C patients without psychiatric disorder underwent IFN-alpha treatment. Proinflammatory and anti-inflammatory cytokines were determined before starting treatment. Presence of a major depressive disorder (MDD) was assessed at baseline and several times during treatment. RESULTS: Baseline soluble interleukin-2 receptor (sIL-2r), interleukin-6 (IL-6), and interleukin-10 (IL-10) concentrations were significantly increased in the five subjects that developed MDD during treatment compared with those that did not, with standardized effect sizes of 1.08, 1.16, and 1.25, respectively, controlling for marijuana use, cigarette smoking, and baseline level of depressive symptoms. CONCLUSIONS: Results suggest that increased immune activation, rather than an epiphenomenon, is a causal risk factor for the development of MDD. 相似文献
3.
Velocity discrimination in the cat 总被引:2,自引:0,他引:2
After considerable training (over 2 years) we measured the just noticeable differences (JNDs) in velocity as a function of reference velocity in three cats. The velocity discrimination curve plotting JNDs in velocity, expressed as Weber fractions as a function of reference velocity is U-shaped with optimal performance at reference speeds between 25 and 60 degrees/sec. The discrimination curve changed little with a tenfold change in slit width. Compared to the human velocity discrimination curve determined with the same test apparatus, the feline curve is narrower and shifted towards faster velocities and larger Weber fractions. These results support our specific linking hypothesis between velocity tuned cells as observed in cortical areas 17 and 18 of the cat, and velocity discrimination. 相似文献
4.
Cytochrome P450 3A4 and P-glycoprotein Activity and Assimilation of Tacrolimus in Transplant Patients with Persistent Diarrhea 总被引:2,自引:0,他引:2
Wim Lemahieu Bart Maes Kristin Verbeke Paul Rutgeerts Karel Geboes Yves Vanrenterghem 《American journal of transplantation》2005,5(6):1383-1391
Renal transplant recipients suffering from persistent diarrhea have been repeatedly reported to have increased tacrolimus (Tac) trough levels. This study aimed to explore this phenomenon in detail in 15 renal transplant recipients with diarrhea, whose immunosuppression consisted of corticosteroids, mofetil mycophenolate and Tac. Both hepatic and intestinal CYP3A4 and PGP activity, important determinants of Tac bioavailability, were assessed, together with global CYP activity and investigations for gastrointestinal infection, function and morphology. Global CYP, CYP3A4, PGP and trough/dose levels of Tac were compared with diarrhea-free controls. In addition, a pharmacokinetic study of Tac was performed in 11 patients affected by diarrhea versus 9 controls. As expected, diarrhea was associated with increased Tac trough levels. An even stronger, significant increase of dose-normalized Tac levels was observed between 90 and 360 min after Tac intake. Time to peak concentration and drug half-life, however, were not altered. In addition, a concomitant decrease (+/-50%) of intestinal PGP activity was noticed in patients with diarrhea. For global CYP, CYP3A4 and hepatic PGP activity no such differences were noted. This pattern was not influenced by the specific cause of diarrhea. These data strongly suggest that persistent diarrhea is associated with an increased oral bioavailability of Tac. 相似文献
5.
The 3-methoxy-4-hydroxyphenylglycol (MHPG) flow, the creatinine flow in 24 h urine and the plasma creatinine level were determined in 42 psychiatric control patients. The creatinine clearance was calculated. The relationship between MHPG flow in 24 h urine and creatinine clearance, creatinine flow, 24 h urinary output, age, sex and weight of the patient were studied by means of single and multiple regression methods. The MHPG flow was significantly correlated with creatinine clearance (r= 0.597), creatinine flow (r = 0.646) and sex of the patient (rpb = 0.434). The variance of the MHPG flow can be explained by the regression with creatinine flow, age and urinary output for at maximum 51.5%. These variables have to be taken into account for the interpretation of data concerning the MHPG flow in subsequent experimental designs. The results of the measurements of the MHPG flow can best be expressed as the residual values obtained after partialling out the predictable component calculated by multiple regression with creatinine flow, age and 24 h urine output. 相似文献
6.
Herlinde Dumez Gunther Guetens Gert De Boeck Martin S Highley Robert A A Maes Allan T van Oosterom Ernst A de Bruijn 《Clinical chemistry and laboratory medicine》2004,42(11):1219-1227
Therapeutic drug monitoring generally focuses on the plasma compartment only. Differentiation between the total plasma concentration and the free fraction (plasma water) has been described for a number of limited drugs. Besides the plasma compartment, blood has also a cellular fraction which has by far the largest theoretical surface and volume for drug transport. It is with anti-cancer drugs that major progress has been made in the study of partition between the largest cellular blood compartment, i.e., erythrocytes, and the plasma compartment. The aim of the present review is to detail the progress made in predicting what a drug does in the body, i.e., pharmacodynamics including toxicity and plasma and/or red blood cell concentration monitoring. Furthermore, techniques generally used in anti-cancer drug monitoring are highlighted. Data for complex Bayesian statistical approaches and population kinetics studies are beyond the scope of this review, since this is generally limited to the plasma compartment only. 相似文献
7.
The authors use injections of botulinum A toxin in treatment of facial spasms. 105 patients (70 patients with blepharospasm, 35 patients with hemispasm) were treated during 4 years. The toxin Wisconsin relieved spasms for an average of 10 weeks. Local complications such as ptosis and diplopia appeared in less than 1/5 of the cases. No general complications were observed. Repeated treatments are necessary. The authors noted a decrease of lacrimal secretion on the treated side in hemifacial spasm and concluded that botulinum A toxin injections could be used as a treatment of epiphora. 相似文献
8.
Piet Borgdorff Geert Jan Tangelder Walter J Paulus 《Journal of the American College of Cardiology》2006,48(4):817-823
OBJECTIVES: We aimed to investigate the effect of parecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, on in vivo shear stress-induced platelet aggregation in a rat model of arterial bypass with focal narrowing. BACKGROUND: Long-term use of COX-2 inhibitors is associated with increased incidence of adverse cardiovascular events, especially in patients with a history of cardiovascular disease. These patients are at risk for thrombotic occlusion of arterial stenoses initiated by shear stress-induced platelet aggregation. METHODS: To mimic the combination of a tight arterial stenosis and high shear stress in rats, an extracorporeal shunt from carotid to femoral artery was compressed by the rollers of a pump. Platelet aggregation was continuously measured by a photometric detector in the shunt. RESULTS: Pretreatment with parecoxib (20 mg/kg) almost doubled shear stress-induced platelet aggregation (188% vs. 100% in control subjects, p = 0.0003). This was accompanied by a fall in plasma 6-keto-prostaglandin F(1alpha) from 100 +/- 25 pg/ml to 36 +/- 11 pg/ml (p < 0.0001). Enhanced platelet aggregation was also observed with high-dose aspirin (150 mg/kg) (146%; p = 0.02) but not with low-dose aspirin (25 mg/kg), which reduced aggregation (68%; p = 0.01). The effect of parecoxib was neutralized by low-dose (1 mg/kg) clopidogrel (from 188% to 92%; p = 0.0001), but not by low-dose aspirin (from 188% to 177%; p = NS). CONCLUSIONS: In the presence of an arterial stenosis, COX-2 inhibitors enhance shear stress-induced platelet aggregation. This enhancement was prevented by low-dose clopidogrel but not by low-dose aspirin. Clopidogrel might therefore allow COX-2 inhibitors to be used without raising risk of thrombotic occlusion. 相似文献
9.
Jan Clement Piet Maes M Muthusethupathi Georgy Nainan Marc van Ranst 《Nephrology, dialysis, transplantation》2006,21(3):826-827
Sir, In a recent Indian serosurvey [1], it was announced that noreports of hantavirus infections in humans from India existed[before 2005]. We wish to point out that serologicaland clinical evidence of hantavirus infection in India was alreadywell documented before 2005. From 1998 on, we screened leptospirosis-suspected cases in Indiafor the only known cosmopolitan hantavirus serotype, Seoul virus(SEOV). Wild rats are the reservoir 相似文献
10.
J M Maes D Rousie C Buchet M M Baralle M Donazzan 《Chirurgie; mémoires de l'Académie de chirurgie》1992,118(10):734-9; discussion 739-40
Among the numerous causes of facial neuralgias, the painful dysfunction syndrome of the manducatory apparatus corresponds to a frequent etiology whose thorough study carried out by a multidisciplinary team over about 500 cases allowed their splitting into several evolutive clinical forms. At present, a number of these forms which are particularly painful, require a disk surgery (dislocation reduction, perforation suture, etc.) and if necessary an articular facet surgery (modelling condylectomy, surfacing, etc.). This study specifies the indications and prognosis for these surgical operations. 相似文献