全文获取类型
收费全文 | 10536篇 |
免费 | 749篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 63篇 |
儿科学 | 362篇 |
妇产科学 | 189篇 |
基础医学 | 1270篇 |
口腔科学 | 188篇 |
临床医学 | 996篇 |
内科学 | 2096篇 |
皮肤病学 | 102篇 |
神经病学 | 919篇 |
特种医学 | 367篇 |
外科学 | 1547篇 |
综合类 | 247篇 |
一般理论 | 9篇 |
预防医学 | 980篇 |
眼科学 | 282篇 |
药学 | 821篇 |
中国医学 | 45篇 |
肿瘤学 | 837篇 |
出版年
2023年 | 41篇 |
2022年 | 70篇 |
2021年 | 203篇 |
2020年 | 132篇 |
2019年 | 222篇 |
2018年 | 226篇 |
2017年 | 168篇 |
2016年 | 194篇 |
2015年 | 210篇 |
2014年 | 355篇 |
2013年 | 464篇 |
2012年 | 755篇 |
2011年 | 787篇 |
2010年 | 404篇 |
2009年 | 399篇 |
2008年 | 663篇 |
2007年 | 790篇 |
2006年 | 737篇 |
2005年 | 727篇 |
2004年 | 660篇 |
2003年 | 627篇 |
2002年 | 568篇 |
2001年 | 85篇 |
2000年 | 72篇 |
1999年 | 87篇 |
1998年 | 119篇 |
1997年 | 118篇 |
1996年 | 90篇 |
1995年 | 84篇 |
1994年 | 73篇 |
1993年 | 79篇 |
1992年 | 61篇 |
1991年 | 39篇 |
1990年 | 46篇 |
1989年 | 44篇 |
1988年 | 41篇 |
1987年 | 39篇 |
1986年 | 45篇 |
1985年 | 47篇 |
1984年 | 54篇 |
1983年 | 38篇 |
1982年 | 54篇 |
1981年 | 52篇 |
1980年 | 49篇 |
1979年 | 26篇 |
1978年 | 31篇 |
1977年 | 25篇 |
1974年 | 23篇 |
1973年 | 30篇 |
1972年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 593 毫秒
101.
Neuropsychological Deficit and Academic Performance in Children and Adolescents Following Traumatic Brain Injury 总被引:1,自引:1,他引:1
Kinsella Glynda; Prior Margot; Sawyer Michael; Murtagh Douglas; Eisenmajer Richard; Anderson Vicki; Bryan Doug; Klug Geoffrey 《Journal of pediatric psychology》1995,20(6):753-767
Evaluated the utility of neuropsychological testing in predictingacademic outcome in children 1 year following traumatic braininjury (TBI). Fifty-one schoolage children who were admittedto hospital after TBI were assessed with a battery of neuropsychologicalmeasures at 3 months postinjury. Academic achievement was assessedat 3 and 12 months postinjury. The neuropsychological batteryincluded intelligence testing and measures of memory, learning,and speed of information processing. Academic outcome was assessedin terms of post-TBI changes in reading, spelling, and arithmetic;changes in teacher ratings of school performance; and changein school placement. According to logistic regression analysis,change in placement from regular to special education at 1-yearpost-TBI was predicted by injury severity and by neuropsychologicalperformance at 3 months post-TBI. Findings suggest that neuropsychologicaltesting is useful in identifying children with special educationalneeds subsequent to TBI. 相似文献
102.
Woodward MJ Best A Sprigings KA Pearson GR Skuse AM Wales A Hayes CM Roe JM Low JC La Ragione RM 《International journal of medical microbiology : IJMM》2003,293(4):299-308
Ruminants are regarded as a primary reservoir for Escherichia coli O157:H7, an important human pathogen. Intimin, encoded by the Locus of Enterocyte Effacement by E. coli O157:H7 organisms, has been cited as one bacterial mechanism of colonisation of the gastrointestinal tract. To confirm this and to test whether a non-toxigenic E. coli O157:H7 strain would colonise and persist in a sheep model, E. coli O157:H7 strain NCTC12900, that lacks Shiga toxin (stx) genes, was evaluated for use in a sheep model of persistence. Following oral inoculation of six-week-old sheep, persistent excretion of NCTC12900 was observed for up to 48 days. E. coli O157-associated attaching-effacing (AE) lesions were detected in the caecum and rectum of one six-week-old lamb, one day after inoculation. This is the first recorded observation of AE lesions in orally inoculated weaned sheep. Also, mean faecal excretion scores of NCTC12900 and an isogenic intimin (eae)-deficient mutant were determined from twenty-four six-week-old orally inoculated sheep. The eae mutant was cleared within 20 days and had lower mean excretion scores at all time points after day one post inoculation compared with the parental strain that was still being excreted at 48 days. Tissues were collected post mortem from animals selected at random from the study groups over the time course of the experiment. The eae mutant was detected in only 1/43 samples but the parental strain was recovered from 64/140 samples primarily from the large bowel although rumen, duodenum, jejunum, and ileum were culture positive especially from animals that were still excreting at and beyond 27 days after inoculation. 相似文献
103.
Roca A Quintó L Abacassamo F Loscertales MP Gómez-Olivé FX Fenwick F Cane PA Saiz JC Toms G Alonso PL 《Journal of medical virology》2003,69(4):579-587
Serological responses have been studied in respiratory syncytial virus (RSV) infected children < 1 year of age attending the outpatient department of the Manhiça District Hospital (Mozambique). Molecular characterization of viral RNA in nasopharyngeal aspirates from the infected children indicated a high level of genetic uniformity among the infecting viruses, all of which belonged to a single genotype of RSV group A. A representative virus strain, Moz00, was isolated from one of the infants and was used, together with the group A strain A2 and the group B strain 8/60, as antigens in the quantification of infant antibody responses. In this study, 97.5% (39/40) and 96.4% (27/28) of infected children produced an antibody response against Moz00 detected by the membrane fluorescent antibody test (MFAT) and the neutralization test (NT), respectively. Seroconversion rates decreased when the A2 and 8/60 strains were used as antigen in MFAT (95.4% and 88.2%, respectively) or NT (81.8% and 54.5%, respectively), indicating that antibody responses had both group‐ and strain‐specific components. Antibodies in convalescent sera of infected children were compared with maternally derived antibodies detected in a group of children also < 1 year of age, but with no evidence of RSV infection. The convalescent sera exhibited reduced neutralizing capacity when the 8/60 strain was used as antigen (P = 0.028), suggesting that the infant antibody response lacks neutralizing capacity against strains of the heterologous virus group. Restricted cross‐reactivity and neutralizing capacity of antibodies generated by young children might be expected to induce only moderate protection in subsequent epidemics against genetically distant strains. J. Med. Virol. 69:579–587, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
104.
Recruitment and baseline epidemiologic profile of participants in the first phase 3 HIV vaccine efficacy trial 总被引:2,自引:0,他引:2
Harro CD Judson FN Gorse GJ Mayer KH Kostman JR Brown SJ Koblin B Marmor M Bartholow BN Popovic V;VAX Study Group 《Journal of acquired immune deficiency syndromes (1999)》2004,37(3):1385-1392
OBJECTIVE: To describe recruitment and baseline epidemiologic characteristics of volunteers in the first phase 3 placebo-controlled trial of a recombinant gp120 HIV vaccine (AIDSVAX B/B). METHODS: Volunteers were gay/bisexual men or women at risk for sexually transmitted HIV infection. Recruitment strategies, demographics, and risk factors were assessed. HIV status was determined by standard HIV-1 antibody assays. Seronegative/viremic HIV infection at enrollment was determined using the HIV-1 nucleic acid test. RESULTS: From June 1998 through October 1999, 5417 of 7185 volunteers screened were enrolled at 61 sites in the United States, Canada, and The Netherlands. Successful recruitment methods included distribution of study information at gay venues, advertising and media coverage, and referrals from volunteers. Most volunteers were altruistically motivated, men (98%), young (median, 36 years), white (83%), well educated (61% college education or more), and at high risk for HIV during the 6 months before enrollment. At baseline, 14 were HIV infected (12 were seronegative but viremic; 2 were seropositive and viremic). CONCLUSION: Men and women at high risk for sexually transmitted HIV infection were successfully recruited for the first phase 3 HIV vaccine efficacy trial. Knowledge of recruitment and baseline epidemiologic characteristics of participants in this trial will provide valuable guidance for designing and conducting future trials. 相似文献
105.
Assessment of ventricular function by radionuclide angiography in patients receiving 4′-epidoxorubicin and mitoxantrone 总被引:1,自引:0,他引:1
Daniel A. Vorobiof Mario Iturralde Geoffrey Falkson 《Cancer chemotherapy and pharmacology》1985,15(3):253-257
Summary Serial assessment of ventricular function by means of radionuclide angiography was performed in 50 patients with malignant neoplasms who received either 4-epidoxorubicin or mitoxantrone for longer than 3 months.In 9 of 30 patients give 4-epidoxorubicin, a decrease of 10% in the left ventricular ejection fraction (LVEF) was documented at doses of 143–1200 mg/m2. Two patients developed clinical signs of cardiotoxicity at a dose of >1000 mg/m2.In 6 of 20 patients given mitoxantrone a decrease of 10% in the LVEF occurred at doses of 26–98 mg/m2.This study was supported in part by a grant from the National Cancer Association of South Africa 相似文献
106.
Anatomical disassociation of amphetamine's rewarding and aversive effects: An intracranial microinjection study 总被引:2,自引:0,他引:2
Amphetamine has rewarding properties in some behavioral paradigms, such as self-administration and conditioned place preference (CPP), but an aversive component is also apparent when the drug is tested with the conditioned taste aversion (CTA) paradigm. The persent study was an attempt to determine the neuroanatomical substrates of the drug's rewarding and aversive effects. Previous evidence suggested that amphetamine's stimulation of activity in dopaminergic synapses is critical for both effects. Amphetamine was therefore micro-injected bilaterally (10 g/0.5 l per side) into six different dopaminergic sites, each in a different group of animals: the medial prefrontal cortex, nucleus accumbens, anteromedial caudate nucleus, lateroventral caudate nucleus, amygdala, and the region subjacent to the area postrema (AP region). The effects of these injections in both the taste and place conditioning paradigms were examined in separate experiments. Of the six sites, a significant CPP was observed only with accumbens injections and a significant CTA was observed only with AP region injections. It was concluded that the accumbens plays a primary role in mediating the rewarding effects of amphetamine and that the AP region plays a primary role in mediating the CTA. This constitutes an anatomical disassociation of amphetamine's rewarding and aversive effects. The differential associative bias of place-reward and taste-aversion learning apparent in the results is discussed.
Offprint requests to: N.M. White 相似文献
107.
This study examined the possibility that amphetamine-induced stereotypy and facilitation of memory consolidation are both mediated by amphetamine's stimulation of dopaminergic activity in the caudate nucleus. In the first experiment, rats were given pairings of a tone and a shock followed by SC amphetamine (2 mg/kg). The amount of stereotypy and increased locomotor activity produced by the injection were measured immediately. Retention of the tone-shock association was evaluated 48 h later by observing the ability of the tone to suppress drinking. The degree of retention was significantly correlated with the amount of stereotypy but not with the amount of locomotion previously measured. In the second experiment, amphetamine was microinjected into the caudate nucleus (10 g/l) and its ability to produce the same three behavioral effects was examined. These injections produced increased stereotypy and improved retention, but no increase in locomotion. The correlation of memory facilitation with stereotypy and the fact that both were produced by intracaudate amphetamine suggest that they may be mediated by the same neuropharmacological substrate, namely amphetamine-induced release of dopamine in the caudate. 相似文献
108.
109.
Lidia Daimiel Víctor Mic Laura Díez-Ricote Paloma Ruiz-Valderrey Geoffrey Istas Ana Rodríguez-Mateos Jos María Ordovs 《Nutrients》2021,13(1)
Beer is a popular beverage and some beneficial effects have been attributed to its moderate consumption. We carried out a pilot study to test if beer and non-alcoholic beer consumption modify the levels of a panel of 53 cardiometabolic microRNAs in plasma and macrophages. Seven non-smoker men aged 30–65 with high cardiovascular risk were recruited for a non-randomised cross-over intervention consisting of the ingestion of 500 mL/day of beer or non-alcoholic beer for 14 days with a 7-day washout period between interventions. Plasma and urine isoxanthohumol were measured to assess compliance with interventions. Monocytes were isolated and differentiated into macrophages, and plasma and macrophage microRNAs were analysed by quantitative real-time PCR. Anthropometric, biochemistry and dietary parameters were also measured. We found an increase in plasma miR-155-5p, miR-328-3p, and miR-92a-3p after beer and a decrease after non-alcoholic beer consumption. Plasma miR-320a-3p levels decreased with both beers. Circulating miR-320a-3p levels correlated with LDL-cholesterol. We found that miR-17-5p, miR-20a-5p, miR-145-5p, miR-26b-5p, and miR-223-3p macrophage levels increased after beer and decreased after non-alcoholic beer consumption. Functional analyses suggested that modulated microRNAs were involved in catabolism, nutrient sensing, Toll-like receptors signalling and inflammation. We concluded that beer and non-alcoholic beer intake modulated differentially plasma and macrophage microRNAs. Specifically, microRNAs related to inflammation increased after beer consumption and decreased after non-alcoholic beer consumption. 相似文献