全文获取类型
收费全文 | 18044篇 |
免费 | 1116篇 |
国内免费 | 142篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 493篇 |
妇产科学 | 378篇 |
基础医学 | 2925篇 |
口腔科学 | 343篇 |
临床医学 | 1488篇 |
内科学 | 4573篇 |
皮肤病学 | 302篇 |
神经病学 | 1823篇 |
特种医学 | 456篇 |
外科学 | 1367篇 |
综合类 | 48篇 |
一般理论 | 5篇 |
预防医学 | 1403篇 |
眼科学 | 208篇 |
药学 | 1350篇 |
中国医学 | 61篇 |
肿瘤学 | 1966篇 |
出版年
2024年 | 24篇 |
2023年 | 196篇 |
2022年 | 389篇 |
2021年 | 666篇 |
2020年 | 394篇 |
2019年 | 544篇 |
2018年 | 587篇 |
2017年 | 487篇 |
2016年 | 551篇 |
2015年 | 598篇 |
2014年 | 758篇 |
2013年 | 1004篇 |
2012年 | 1628篇 |
2011年 | 1629篇 |
2010年 | 893篇 |
2009年 | 810篇 |
2008年 | 1322篇 |
2007年 | 1222篇 |
2006年 | 1162篇 |
2005年 | 1011篇 |
2004年 | 919篇 |
2003年 | 772篇 |
2002年 | 670篇 |
2001年 | 99篇 |
2000年 | 65篇 |
1999年 | 107篇 |
1998年 | 126篇 |
1997年 | 101篇 |
1996年 | 95篇 |
1995年 | 52篇 |
1994年 | 47篇 |
1993年 | 50篇 |
1992年 | 32篇 |
1991年 | 33篇 |
1990年 | 28篇 |
1989年 | 13篇 |
1988年 | 16篇 |
1987年 | 23篇 |
1986年 | 15篇 |
1985年 | 10篇 |
1984年 | 21篇 |
1983年 | 16篇 |
1982年 | 14篇 |
1981年 | 11篇 |
1980年 | 9篇 |
1979年 | 8篇 |
1974年 | 7篇 |
1973年 | 11篇 |
1971年 | 9篇 |
1968年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Cristina Benatti Silvia Alboni Giacomo Capone Daniela Corsini Federica Caggia Nicoletta Brunello Fabio Tascedda Joan M.C. Blom 《International journal of developmental neuroscience》2009,27(7):661-668
Protracted or recurrent pain and inflammation in the early neonatal period may cause long-lasting changes in central neural function. However, more research is necessary to better characterize the long-term behavioral sequelae of such exposure in the neonatal period. Objectives: (1) to study whether timing of postnatal exposure to persistent inflammation alters responsiveness to thermal pain in the adult animal; (2) to assess whether animals experiencing early postnatal chronic inflammation display altered anxiety related behavior; (3) to study the importance of genetic background. Newborn mice (outbred strain, CD1 and F1 hybrid strain, B6C3F1) received an injection of Complete Freund's Adjuvant (CFA) or saline on either postnatal day 1 or 14 (PND1; PND14) into the left hind paw. Pain to radiant heat and anxiety were examined in 12-week-old adult animals. Adult baseline PWL was significantly decreased in CD1 mice exposed to CFA on PND 1 and 14 as compared to their saline treated counterparts. B6C3F1 mice exposed to CFA on PND14 showed markedly reduced baseline PWL compared to the PND14 saline group. Persistent inflammation experienced by B6C3F1 mice on PND1 failed to affect baseline adult thermal responsiveness. Adult mice, CD1 and B6C3F1, displayed low anxiety traits only if they had been exposed to persistent inflammation on PND1 and not on PND14. Our research suggests a role for genetic background in modulating long-term behavioral consequences of neonatal persistent inflammation: the data support the hypothesis that pain experienced very early in life differentially affects adult behavioral and emotional responsiveness in outbred (CD1) and hybrid mice (B6C3F1). 相似文献
13.
14.
15.
Estrella Fernández Fabrellas Luis Almenar Bonet Silvia Ponce Pérez José Antonio Moro López Rafael Blanquer Olivas Antonio Salvador Sanz 《Archivos de bronconeumologia》2009,45(4):173-180
Introduction and objectiveWhen sleep apnea-hypopnea syndrome (SAHS) and cardiovascular disease occur concurrently, prognosis is affected. Echocardiography can detect structural cardiac abnormalities but using this technique in all patients would place a heavy burden on resources. The objective of this study was to investigate whether the N-terminal fraction of brain natriuretic peptide (NT-proBNP) can be used as a marker for silent heart disease.Patients and methodsNT-proBNP concentration was measured in the 114 consecutive patients with SAHS who underwent echocardiography before starting treatment. Left and right ventricular systolic and diastolic function, as well as structural abnormalities, were studied. Correlations between NT-proBNP concentration and the abnormalities detected were investigated. A receiver operating characteristics (ROC) curve was plotted for NT-proBNP concentration and cardiac abnormalities.ResultsData for 98 patients were finally analyzed. NT-proBNP concentration was significantly correlated with ventricular septal thickness (r=0.63), posterior wall thickness (r=0.45), and left ventricular enddiastolic diameter (r=0.51) (P<.0001 for all correlations). The area under the ROC curve was significant (0.870; 95% confidence interval, 0.801-0.939; P<.0001). Assuming that specificity would be more useful for clinical practice, we calculated that NT-proBNP concentrations below 100 and 200 pg/mL could rule out structural abnormalities with a reliability of 90% and 100%, respectively.ConclusionsNT-proBNP concentration was strongly correlated with echocardiographic abnormalities and so could be a useful tool for identifying patients who should be referred to the cardiologist. 相似文献
16.
17.
Fernanda Martini Alfredo Corallini Veronica Balatti Silvia Sabbioni Cecilia Pancaldi Mauro Tognon 《Infectious agents and cancer》2007,2(1):13-12
Simian virus 40 (SV40) is a monkey virus that was administered to human populations by contaminated vaccines which were produced
in SV40 naturally infected monkey cells. 相似文献
18.
Varsha Patki Joe Virbasius William S. Lane Ban-Hock Toh Howard S. Shpetner Silvia Corvera 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(14):7326-7330
Phosphatidylinositol 3-kinases (PI 3-kinases) have been implicated in membrane trafficking in the secretory and endocytic pathways of yeast and mammalian cells, but the molecular mechanisms by which these lipid kinases operate are not known. Here we identify a protein of 170 kDa that is rapidly released from cell membranes in response to wortmannin, a potent inhibitor of mammalian PI 3-kinases. The amino acid sequence of peptides from p170 reveal its identity to early endosomal antigen (EEA) 1, an endosomal antigen with homology to several yeast proteins genetically implicated in membrane trafficking. Immunofluorescence analysis of 3T3-L1 adipocytes with antisera against p170/EEA1 reveal a punctate peripheral pattern that becomes diffuse in response to wortmannin. In vitro, p170/EEA1 binds specifically to liposomes containing PIns(3)P, suggesting that the effect of wortmannin on cells is due to inhibition of PIns(3)P production. Thus, p170/EEA1 may define a family of proteins that mediate the regulatory effects of 3′-phosphoinositides on membrane trafficking in yeast and mammalian cells. 相似文献
19.
20.
Alfredo Marzano Silvia Gaia Valeria Ghisetti Silvia Carenzi Alberto Premoli Wilma Debernardi-Venon Carlo Alessandria Alessandro Franchello Mauro Salizzoni Mario Rizzetto 《Liver transplantation》2005,11(4):402-409
Hepatitis B virus (HBV) recurrence after liver transplantation is significantly reduced by prophylaxis with hepatitis B immune globulins (HBIG) or antiviral drugs in nonreplicating patients and by the combination of both drugs in replicating patients. However, the load of HBV DNA, which defines replicating status in patients undergoing liver transplantation, remains unclear. This study analyzes the correlation between the viral load, tested with a single amplified assay, at the time of liver transplantation, and the risk of hepatitis B recurrence in 177 HBV carriers who underwent transplantation in a single center from 1990 to 2002. Overall, HBV relapsed after surgery in 15 patients (8.5%) with a 5- and 8-year actuarial rate of recurrence of 8% and 21%, respectively. After liver transplantation hepatitis B recurred in 9% of 98 selected subjects treated only with immune globulins and in 8% of 79 viremic patients who received immune globulins and lamivudine (P = NS). A linear correlation was observed between recurrence and viral load at the time of surgery. In transplant patients with HBV DNA higher than 100,000 copies/mL, 200-99,999 copies/mL, and DNA undetectable by amplified assay, hepatitis B recurred in 50%, 7.5%, and 0% of patients, respectively. Overall, a viral load higher than 100,000 copies/mL at the time of liver transplantation was significantly associated with hepatitis B recurrence (P = .0003). In conclusion, spontaneous or antiviral-induced HBV DNA viral load at the time of surgery classifies the risk of HBV recurrence after liver transplantation and indicates the best prophylaxis strategy. 相似文献