全文获取类型
收费全文 | 7110篇 |
免费 | 433篇 |
国内免费 | 122篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 119篇 |
妇产科学 | 223篇 |
基础医学 | 779篇 |
口腔科学 | 142篇 |
临床医学 | 780篇 |
内科学 | 990篇 |
皮肤病学 | 66篇 |
神经病学 | 203篇 |
特种医学 | 172篇 |
外科学 | 444篇 |
综合类 | 847篇 |
预防医学 | 1327篇 |
眼科学 | 23篇 |
药学 | 823篇 |
1篇 | |
中国医学 | 136篇 |
肿瘤学 | 554篇 |
出版年
2024年 | 11篇 |
2023年 | 82篇 |
2022年 | 176篇 |
2021年 | 256篇 |
2020年 | 217篇 |
2019年 | 209篇 |
2018年 | 205篇 |
2017年 | 199篇 |
2016年 | 218篇 |
2015年 | 237篇 |
2014年 | 446篇 |
2013年 | 557篇 |
2012年 | 506篇 |
2011年 | 503篇 |
2010年 | 333篇 |
2009年 | 357篇 |
2008年 | 356篇 |
2007年 | 381篇 |
2006年 | 322篇 |
2005年 | 286篇 |
2004年 | 238篇 |
2003年 | 201篇 |
2002年 | 189篇 |
2001年 | 125篇 |
2000年 | 120篇 |
1999年 | 104篇 |
1998年 | 77篇 |
1997年 | 77篇 |
1996年 | 74篇 |
1995年 | 68篇 |
1994年 | 62篇 |
1993年 | 48篇 |
1992年 | 36篇 |
1991年 | 25篇 |
1990年 | 31篇 |
1989年 | 37篇 |
1988年 | 22篇 |
1987年 | 28篇 |
1986年 | 24篇 |
1985年 | 29篇 |
1984年 | 21篇 |
1983年 | 17篇 |
1982年 | 23篇 |
1981年 | 20篇 |
1980年 | 14篇 |
1979年 | 11篇 |
1978年 | 12篇 |
1977年 | 13篇 |
1975年 | 10篇 |
1971年 | 10篇 |
排序方式: 共有7665条查询结果,搜索用时 15 毫秒
1.
《Journal of Radiology Nursing》2022,41(3):170-179
BackgroundDespite indications for the removal of temporary inferior vena cava (IVC) filters, many filters are unintentionally left in place, predisposing patients to adverse outcomes.ObjectiveThis quality improvement study set out to determine the impact of an IVC filter retrieval protocol on filter retrieval rates and patients lost to follow-up for patients who had undergone placement of a temporary IVC filter.MethodsFollowing a quasi-experimental design, data of all consecutive patients who underwent insertion of a temporary IVC filter for a period of 24-month preprotocol and 12-month postprotocol were compared.ResultsFilter retrieval rates of eligible filters increased from 64.2% to 100%; patients lost to follow-up decreased from 35.9% to 0% (p < .01, both outcomes).ConclusionAdoption of a comprehensive IVC filter protocol by the service that implants these devices can improve filter retrieval rates and decrease patients being lost to follow-up. 相似文献
2.
3.
4.
Geneticists have, for years, understood the nature of genome‐wide association studies using common genomic variants. Recently, however, focus has shifted to the analysis of rare variants. This presents potential problems for researchers, as rare variants do not always behave in the same way common variants do, sometimes rendering decades of solid intuition moot. In this paper, we present examples of the differences between common and rare variants. We show why one must be significantly more careful about the origin of rare variants, and how failing to do so can lead to highly inflated type I error. We then explain how to best avoid such concerns with careful understanding and study design. Additionally, we demonstrate that a seemingly low error rate in next‐generation sequencing can dramatically impact the false‐positive rate for rare variants. This is due to the fact that rare variants are, by definition, seen infrequently, making it hard to distinguish between errors and real variants. Compounding this problem is the fact that the proportion of errors is likely to get worse, not better, with increasing sample size. One cannot simply scale their way up in order to solve this problem. Understanding these potential pitfalls is a key step in successfully identifying true associations between rare variants and diseases. 相似文献
5.
B. Midouni E. Mehiri A. Ghariani H. Draoui L. Essalah I. Bouzouita D. Raoult L. Slim-Saidi P.E. Fournier 《International journal of antimicrobial agents》2019,53(1):63-69
Objectives
This study aimed to explore the genetic diversity of Streptococcus pneumoniae isolates in a Tunisian pneumology hospital.Methods
A total of 141 S. pneumoniae strains isolated between 2009–2016 in the microbiology laboratory at A. Mami Hospital of Pneumology were investigated. Antimicrobial susceptibility testing was performed the disk diffusion method. MICs of penicillin G, amoxicillin and cefotaxime were determined by Etest. Serotyping was inferred from the results of multiplex PCR targeting 40 serotypes. Sequence types (STs) were determined by multilocus sequence typing (MLST).Results
Among the 141 S. pneumoniae isolates, 98 (69.5%) were resistant to erythromycin. Evaluation of β-lactam susceptibility showed that 90 strains (63.8%) were non-susceptible to penicillin, whereas 48 (34.0%) had decreased susceptibility to amoxicillin and 21 (14.9%) to cefotaxime. Twenty-five serotypes were detected, and 10 isolates were classified as non-typeable. Vaccine coverage was 56.7%, 60.3% and 75.2% for pneumococcal conjugate vaccine 7 (PCV7), PCV10 and PCV13, respectively. Overall, 73 STs were identified, including 23 described for the first time. The most frequent STs were ST179 (n?=?17), ST3772 (n?=?14), ST2918 (n?=?10) and ST4003 (n?=?5), related to serotypes 19F, 19A, 14 and 23F, respectively. Moreover, 110 strains were classified within 45 STs. Three international antimicrobial-resistant clones were found, including Denmark14-ST230 (n?=?22), Spain9V-ST156 (n?=?22) and Portugal19F-ST177 (n?=?20).Conclusion
This study emphasises the clonal and international dissemination of antimicrobial-resistant S. pneumoniae clones. Significant differences in genetic variation were documented by MLST within the various serotypes identified. 相似文献6.
Rebecca Carman Lesley Andrew Amanda Devine Jacques Oosthuizen 《Australian and New Zealand journal of public health》2019,43(6):563-569
Objective: To identify behavioural barriers of service provision within general practice that may be impacting the vaccination coverage rates of Aboriginal children in Perth, Western Australia (WA). Methods: A purposive developed survey was distributed to 316 general practices across Perth and three key informant interviews were conducted using a mixed‐methods approach. Results: Of the surveyed participants (n=101), 67.4% were unaware of the low vaccination coverage in Aboriginal children; 64.8% had not received cultural sensitivity training in their workplace and 46.8% reported having inadequate time to follow up overdue child vaccinations. Opportunistic vaccination was not routinely performed by 30.8% of participants. Key themes identified in the interviews were awareness, inclusion and cultural safety. Conclusion: Inadequate awareness of the current rates, in association with a lack of cultural safety training, follow‐up and opportunistic practice, may be preventing greater vaccination uptake in Aboriginal children in Perth. Cultural safety is a critical component of the acceptability and accessibility of services; lack of awareness may restrict the development of strategies designed to equitably address low coverage. Implications: The findings of this study provide an opportunity to raise awareness among clinicians in general practice and inform future strategies to equitably deliver targeted vaccination services to Aboriginal children. 相似文献
7.
抗生素的定义,首先来自于20世纪40年代链霉素的发现。在随后的几十年中,其他氨基糖苷类抗生素家族被大量发现并广泛应用,一度成为抗革兰阴性菌感染的首选抗生素。但由于其毒副作用较大,并且细菌对其不断产生耐药性,加上其他结构类别的新型抗生素的不断发现,使其一度几乎退出历史舞台。然而随着多重耐药细菌引起的感染率急剧上升,人们开始关注氨基糖苷类抗生素作为几种重要的治疗革兰阴性病原体的方案之一,并且发掘了其在治疗感染性疾病、艾滋病和遗传性疾病的潜力,使这个“老牌”抗生素重焕生机。 相似文献
8.
Mhamed 《Computerized medical imaging and graphics》2006,30(8):447-451
The aim in this work is to report a new method to calculate parametric images from a single scan acquisition with positron emission tomography (PET) and fluorodeoxyglucose (FDG) in the human brain without blood sampling. It is usually practical for research or clinical purposes to inject the patient in an isolated room and to start the PET acquisition only for some 10–20 min, about 30 min after FDG injection. In order to calculate the cerebral metabolic rates for glucose (CMRG), usually several blood samples are required. The proposed method considers the relation between the uptake of the tracer in the cerebellum as a reference tissue and the population based input curve. Similar results were obtained for CMRG values with the present method in comparison to the usual autoradiographic and the non-linear least squares fitting of regions of interest. 相似文献
9.
L. Lupo V. De Grandi E. Ganci A. Nastri S. Ielo A. Mistretta G. Giammanco 《European journal of epidemiology》1989,5(3):400-402
A longitudinal survey (February 1984 - January 1985) on the incidence of acute diarrhea episodes in a sample of 8,164 children (aged 0–12 years) living in southeastern Sicily was carried out by means of weekly telephone interviews with doctors practising in the territory. The incidence rate was 0.479 (0.472–0.485 95% C.I.) per child per year and the frequency of episodes was significantly higher (p < 0.001) in children aged 0–4 years (0.86). Diarrhea was more frequent in industrial areas than in rural ones, and almost half (45.1%) of the total episodes had a mild course. No death from diarrhea occurred and admission to hospital was reported for 8.4% of all cases.Corresponding author. 相似文献
10.
Bergner Raoul; Hoffmann Martin; Riedel Klaus-Dieter; Mikus Gerd; Henrich Dirk M.; Haefeli Walter E.; Uppenkamp Michael; Walter-Sack Ingeborg 《Nephrology, dialysis, transplantation》2006,21(4):1019-1023
To cover intermediate sensitive Candida glabrata in ICU patients,fluconazole plasma peak levels at least in the range of 1632µg/ml appear necessary for treatment. Previous studiesdid not reach these fluconazole levels under continuous veno-venoushaemofiltration (CVVHF) with dosages of 200600 mg fluconzoledaily. In the present study, nine patients simultaneously requiringCVVHF for treatment of acute oligoanuric renal failure and antimycotictherapy of Candida septicemia received fluconazole 800 mg/day.Fluconazole plasma levels were determined to evaluate whetherthis dosage is adequate to reach the advised fluconazole levels.Patients were dialysed on two consecutive days with an ultrafiltrationrate (UF) of 1000 ml/h or 2000 ml/h, respectively, in a randomizedorder. The predilution was 800 ml/h and 1800 ml/h, respectively.The treatment was tolerated without adverse effects. All patientsreached plasma fluconazole concentrations between 16 and 32µg/ml, remaining in this range for a minimum of 1 up to24 h with a mean of 9.6 h and a UF rate of 2000 ml/h, and 15.7h with a UF rate of 1000 ml/h. So far, there are no in vivodata on the fluconazole plasma concentrations required for effectivetreatment. However, our data demonstrate, that at least thefluconazole concentrations desirable on the basis of in vitrosusceptibility testing can be reached in critically ill patientson CVVHF in an ICU setting. However, in these patients, 800mg fluconazole/day are necessary to achieve fungicidal drugconcentrations. 相似文献