全文获取类型
收费全文 | 15118篇 |
免费 | 803篇 |
国内免费 | 82篇 |
专业分类
耳鼻咽喉 | 132篇 |
儿科学 | 326篇 |
妇产科学 | 305篇 |
基础医学 | 1999篇 |
口腔科学 | 430篇 |
临床医学 | 1172篇 |
内科学 | 3921篇 |
皮肤病学 | 259篇 |
神经病学 | 1204篇 |
特种医学 | 360篇 |
外国民族医学 | 1篇 |
外科学 | 2311篇 |
综合类 | 53篇 |
一般理论 | 6篇 |
预防医学 | 953篇 |
眼科学 | 154篇 |
药学 | 863篇 |
中国医学 | 46篇 |
肿瘤学 | 1508篇 |
出版年
2023年 | 80篇 |
2022年 | 152篇 |
2021年 | 307篇 |
2020年 | 203篇 |
2019年 | 310篇 |
2018年 | 376篇 |
2017年 | 269篇 |
2016年 | 322篇 |
2015年 | 373篇 |
2014年 | 510篇 |
2013年 | 674篇 |
2012年 | 1050篇 |
2011年 | 1127篇 |
2010年 | 594篇 |
2009年 | 612篇 |
2008年 | 925篇 |
2007年 | 996篇 |
2006年 | 918篇 |
2005年 | 983篇 |
2004年 | 889篇 |
2003年 | 785篇 |
2002年 | 775篇 |
2001年 | 248篇 |
2000年 | 215篇 |
1999年 | 209篇 |
1998年 | 149篇 |
1997年 | 113篇 |
1996年 | 121篇 |
1995年 | 124篇 |
1994年 | 112篇 |
1993年 | 95篇 |
1992年 | 120篇 |
1991年 | 123篇 |
1990年 | 112篇 |
1989年 | 92篇 |
1988年 | 90篇 |
1987年 | 88篇 |
1986年 | 95篇 |
1985年 | 98篇 |
1984年 | 80篇 |
1983年 | 46篇 |
1982年 | 53篇 |
1981年 | 38篇 |
1980年 | 35篇 |
1979年 | 42篇 |
1978年 | 35篇 |
1977年 | 27篇 |
1976年 | 27篇 |
1975年 | 32篇 |
1973年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Eugenio Baraldi Giovanni Montini Stefania Zanconato Graziella Zacchello Franco Zacchello 《Pediatric nephrology (Berlin, Germany)》1990,4(6):623-626
The aim of this study was to evaluate the effect of correction of chronic anaemia on the physical performance and the cardiovascular response to effort in children with end-stage renal disease (ESRD) maintained by haemodialysis. Seven patients (mean age 13.9 years) underwent triangular-type treadmill exercise testing before [haemoglobin (Hb) 6.3±0.9 g/dl] and after (Hb 11.2±1.2 g/dl) anaemia correction with recombinant human erythropoietin (rHuEPO). After treatment, the work-load reached, the peak oxygen uptake and average ventilatory anaerobic threshold (VAT) values were significantly increased (P<0.01,P<0.001,P<0.05 respectively). VAT values, expressed as a percentage of normal values, increased from 55.7±16.6% to 82.4±21%. This improvement correlated well with the increase in Hb (r=0.79). Oxygen pulse also increased significantly, when tested after anacmia correction. In conclusion, these data demonstrate that when the anaemia of children with ESRD is corrected with rHuEPO, there is a clear improvement in acrobic work capacity and effort tolerance. 相似文献
22.
23.
24.
25.
Franco Guzzetta 《Child's nervous system》1991,7(8):417-424
Neonatal pathology comprises a large array of cerebral lesions due to ischemic and/or hemorrhagic mechanisms. Pathogenesis, neuropathology, clinical settings in the acute stages as well as short and long-term outcome are discussed. 相似文献
26.
Dr. Franco Zunino Brunella Barbieri Ornella Bellini Anna Maria Casazza Cristina Geroni Fernando Giuliani Antonio Ciana Giorgio Manzini Franco Quadrifoglio 《Investigational new drugs》1986,4(1):17-23
Summary The chromophore-modified derivative of doxorubicin, 4-demethyl-6-0-methyl-doxorubicin, has been tested for antitumor activity in a range of experimental murine tumor systems. In contrast to the inactive 6-0-methyl derivative of daunorubicin, 4-demethyl-6-0-methyl-doxorubicin provided antitumor effects comparable to that of the parent compound. In addition, detailed DNA-interaction studies showed that the doxorubicin derivative retains the ability to bind DNA by the intercalation mechanism. However, the binding affinity was appreciably reduced following structural modification in the anthraquinone chromophore. On the basis of the proposed models of intercalation, these results could be rationalized in terms of steric influence of the bulky methoxy group. The results of this study are in agreement with the correlation already observed between DNA binding and relative antitumor activity of anthracyclines. 相似文献
27.
The optical resolution of (R,S)-1-amino-2,3-propanediol was carried out in water with (S)(+)- and (R)(?)-2-(6-methoxy-2-naphthyl)propanoic acid according to Marckwald but using half the quantity of the optically active acid, the other half being constituted by hydrochloric acid. 相似文献
28.
29.
Joana Correia Fátima Franco Silva Carla Roque Henrique Vieira Luís Augusto Providéncia 《Revista portuguesa de cardiologia》2007,26(4):335-343
BACKGROUND: High rates of morbidity and mortality are observed in patients with advanced heart failure (AHF). AHF is now considered the most costly syndrome in cardiology owing to the substantial economic burden associated with hospitalizations for acute decompensation. A management program that involves specialized follow-up by a multidisciplinary team has been suggested as a desirable strategy for improving outcomes for these patients. ObjectivE: To evaluate the impact of a specialized outpatient heart failure (HF) follow-up program for patients with AHF on frequency and duration of hospitalization for HF and functional status. METHODS: We retrospectively studied 167 consecutive patients with AHF who were referred to the outpatient HF follow-up program in our institution between January and November 2002, of whom 147 followed for > or =30 days were included in the analysis. In addition to demographic and baseline clinical characteristics, HF medication and NYHA functional class, the number and duration of hospitalizations for HF during the previous 12 months were recorded and compared at the time of referral and after a follow-up period of 6.5+/-3 months. RESULTS: Of the 147 patients analyzed (aged 60.8+/-13 years; 79% male; left ventricular ejection fraction 27+/-11%), 67% were in NYHA functional class III, 20% in class II and 13% in class IV at the time of referral. There was a significant improvement in functional class during the mean follow-up period: 55% of the patients were in class III, 37% in class II, 5% in class I and 3% in class IV (p<0.0001). The proportion of patients on beta-blockers or spironolactone increased from 33% and 51% at the time of referral to 69% and 71% respectively after referral (p<0.0001). In the 12 months before referral, 39% of the patients had been hospitalized for acute decompensation of HF (87 hospitalizations - mean 7.2/month) versus 13% of the patients during the mean follow-up period (25 hospitalizations - 3.8/month, p<0.0001). No significant differences were found in the proportion of patients on angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, digoxin or diuretics, or in the mean duration of hospitalization before and after referral. ConclusioN: The specialized follow-up of patients with AHF by a team with expertise in HF resulted in significant therapeutic optimization. Increased use of beta-blockers and spironolactone was associated with significant improvement in functional capacity and significant reduction in hospitalizations. 相似文献
30.
Ana C Mendes M Madalena Caldeira Claudia Silva Shawn C Burgess Matthew E Merritt Filipe Gomes Cristina Barosa Teresa C Delgado Fatima Franco Pedro Monteiro Luis Providencia John G Jones 《Magnetic resonance in medicine》2006,56(5):1121-1125
Menthol glucuronide was isolated from the urine of a healthy 70-kg female subject following ingestion of 400 mg of peppermint oil and 6 g of 99% [U-(13)C]glucose. Glucuronide (13)C-excess enrichment levels were 4-6% and thus provided high signal-to-noise ratios (SNRs) for confident assignment of (13)C-(13)C spin-coupled multiplet components within each (13)C resonance by (13)C NMR. The [U-(13)C]glucuronide isotopomer derived via direct pathway conversion of [U-(13)C]glucose to [U-(13)C]UDP-glucose was resolved from [1,2,3-(13)C(3)]- and [1,2-(13)C(2)]glucuronide isotopomers derived via Cori cycle or indirect pathway metabolism of [U-(13)C]glucose. In a second study, a group of four overnight-fasted patients (63 +/- 10 kg) with severe heart failure were given peppermint oil and infused with [U-(13)C]glucose for 4 hr (14 mg/kg prime, 0.12 mg/kg/min constant infusion) resulting in a steady-state plasma [U-(13)C]glucose enrichment of 4.6% +/- 0.6%. Menthol glucuronide was harvested and glucuronide (13)C-isotopomers were analyzed by (13)C NMR. [U-(13)C]glucuronide enrichment was 0.6% +/- 0.1%, and the sum of [1,2,3-(13)C(3)] and [1,2-(13)C(2)]glucuronide enrichments was 0.9% +/- 0.2%. From these data, flux of plasma glucose to hepatic UDPG was estimated to be 15% +/- 4% that of endogenous glucose production (EGP), and the Cori cycle accounted for at least 32% +/- 10% of GP. 相似文献