全文获取类型
收费全文 | 3418篇 |
免费 | 236篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 59篇 |
儿科学 | 134篇 |
妇产科学 | 92篇 |
基础医学 | 482篇 |
口腔科学 | 127篇 |
临床医学 | 356篇 |
内科学 | 654篇 |
皮肤病学 | 26篇 |
神经病学 | 270篇 |
特种医学 | 106篇 |
外科学 | 340篇 |
综合类 | 26篇 |
一般理论 | 5篇 |
预防医学 | 309篇 |
眼科学 | 60篇 |
药学 | 348篇 |
中国医学 | 1篇 |
肿瘤学 | 264篇 |
出版年
2023年 | 16篇 |
2022年 | 28篇 |
2021年 | 45篇 |
2020年 | 58篇 |
2019年 | 75篇 |
2018年 | 89篇 |
2017年 | 70篇 |
2016年 | 99篇 |
2015年 | 100篇 |
2014年 | 114篇 |
2013年 | 185篇 |
2012年 | 238篇 |
2011年 | 225篇 |
2010年 | 143篇 |
2009年 | 138篇 |
2008年 | 239篇 |
2007年 | 241篇 |
2006年 | 252篇 |
2005年 | 194篇 |
2004年 | 195篇 |
2003年 | 160篇 |
2002年 | 183篇 |
2001年 | 31篇 |
2000年 | 19篇 |
1999年 | 27篇 |
1998年 | 43篇 |
1997年 | 41篇 |
1996年 | 52篇 |
1995年 | 29篇 |
1994年 | 25篇 |
1993年 | 24篇 |
1992年 | 15篇 |
1991年 | 19篇 |
1990年 | 23篇 |
1989年 | 26篇 |
1988年 | 21篇 |
1987年 | 16篇 |
1986年 | 18篇 |
1985年 | 17篇 |
1984年 | 18篇 |
1983年 | 9篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1979年 | 14篇 |
1978年 | 14篇 |
1977年 | 10篇 |
1975年 | 9篇 |
1972年 | 4篇 |
1967年 | 5篇 |
排序方式: 共有3659条查询结果,搜索用时 15 毫秒
81.
82.
Norethisterone Treatment, a Major Risk-Factor for Veno-Occlusive Disease in the Liver After Allogeneic Bone Marrow Transplantation 总被引:1,自引:0,他引:1 下载免费PDF全文
Hagglund Hans; Remberger Mats; Klaesson Sven; Lonnqvist Berit; Ljungman Per; Ringden Olle 《Blood》1998,92(12):4568-4572
In this single-center study, we retrospectively analyzed incidenceand risk factors for hepatic veno-occlusive disease (VOD) in 249 consecutive patients who underwent allogeneic hematopoietic stem celltransplantation between January 1990 and June 1995. Twenty-four of the249 transplanted patients developed VOD. The probabilities ofdeveloping VOD were 17% among women and 7% in men (P = .01). In women treated with norethisterone, the incidence was 27%compared with 3% in women without this treatment (P = .007).One-year survival rates were 17% and 73% in patients with (n = 24)or without VOD (n = 225), respectively. The use of heparin prophylaxis (100 IE/kg/24 hours for 1 month) did not alter the incidence or 1-year mortality of VOD. In multivariate analysis, thefollowing risk factors were significant: norethisterone treatment (P < .001), bilirubin >26 µmol/L before bone marrowtransplantation (BMT) (P = .002), one HLA-antigen mismatch(P = .003), previous abdominal irradiation (P = .02), and conditioning with busulphan (P = .02). Ourconclusion is that norethisterone treatment should not be used inpatients undergoing BMT and heparin prophylaxis did not affect theincidence or mortality of VOD. 相似文献
83.
Olle Muren Ehsan Akbarian Mats Salemyr Henrik Bodén Thomas Eisler André Stark Olof Sk?ldenberg 《Acta orthopaedica》2015,86(5):569-574
Background and purpose
We have previously shown that during the first 2 years after total hip arthroplasty (THA), periprosthetic bone resorption can be prevented by 6 months of risedronate therapy. This follow-up study investigated this effect at 4 years.Patients and methods
A single-center, double-blind, randomized placebo-controlled trial was carried out from 2006 to 2010 in 73 patients with osteoarthritis of the hip who were scheduled to undergo THA. The patients were randomly assigned to receive either 35 mg risedronate or placebo orally, once a week, for 6 months postoperatively. The primary outcome was the percentage change in bone mineral density (BMD) in Gruen zones 1 and 7 in the proximal part of the femur at follow-up. Secondary outcomes included migration of the femoral stem and clinical outcome scores.Results
61 of the 73 patients participated in this 4-year (3.9- to 4.1-year) follow-up study. BMD was similar in the risedronate group (n = 30) and the placebo group (n = 31). The mean difference was −1.8% in zone 1 and 0.5% in zone 7. Migration of the femoral stem, the clinical outcome, and the frequency of adverse events were similar in the 2 groups.Interpretation
Although risedronate prevents periprosthetic bone loss postoperatively, a decrease in periprosthetic BMD accelerates when therapy is discontinued, and no effect is seen at 4 years. We do not recommend the use of risedronate following THA for osteoarthritis of the hip.Adaptive bone remodeling around the femoral stem following total hip arthroplasty (THA) results in regional loss of bone mass, especially in proximal parts of the femur—most of which takes place within the first postoperative year (Bodén et al. 2006, Sköldenberg et al. 2006). Periprosthetic bone loss may predispose to periprosthetic fracture, aseptic loosening, and difficulties at revision surgery (Lindahl 2007, Streit et al. 2011, Sköldenberg et al. 2014).The bisphosphonate (BP) risedronate has been used successfully to prevent osteoporotic fractures, mainly in the hip and vertebrae, by inhibiting osteoclast activity (McClung et al. 2001). In recent years, the possible use of BPs to prevent or ameliorate periprosthetic adaptive bone resorption, osteolysis, and implant migration has been investigated thoroughly in animal models and humans. The short-term results of several studies showing the effects of postoperative BP treatment in reducing periprosthetic bone loss up to a year after the arthroplasty have already been published (Venesmaa et al. 2001, Wilkinson et al. 2001, Hennigs et al. 2002, Wilkinson et al. 2005, Arabmotlagh et al. 2006).We have previously found that risedronate given once a week for 6 months after THA reduces periprosthetic bone resorption around an uncemented femoral stem in the first and second postoperative year (Sköldenberg et al. 2011). We now report the 4-year outcome in the same cohort. 相似文献84.
Eva Ludvigsen Carina Carlsson Eva Tiensuu Janson Stellan Sandler Mats Stridsberg 《Upsala journal of medical sciences》2015,120(3):157-168
Background
Somatostatin acts through five receptor subtypes (SSTRs 1–5). We aimed to investigate SSTRs mRNA expression and protein distribution in whole rat embryos, with special emphasis on the pancreas.Material and methods
Rat embryos were collected on embryonal days 10, 11, 12, 14, 15, 17, 19, 21, and at birth. Presence of SSTRs was investigated with RT-PCR techniques and immunohistochemistry.Results
There was no SSTR5 mRNA expression in the whole rat embryos. All SSTR1–5 proteins were observed at embryonal day 10, but the localization varied between the different subtypes. From day 11 to birth SSTRs protein presence increased with time in major structures such as skin and cartilage. It remained similar over time in the heart and liver. In the fetal pancreas mRNA expression of SSTR2 and 4 was detected at day 14, and there was an increase up to birth. Only SSTR1 protein co-localized to a higher extent with the islet hormones studied. SSTR2 was present in all islet endocrine cells except for β-cells. In contrast, the immunostaining for SSTR3–4 was co-localized with insulin and PP, and, finally, SSTR5 with glucagon and pancreatic polypeptide. In mRNA isolated from whole rat embryos SSTR1-2 and SSTR4 expression showed a peak at day 14, while SSTR3 mRNA was not present until day 15.Conclusion
The present data suggest a role for SSTRs during the development of the rat embryo. Subsequent functional studies may elucidate regulatory roles of specific SSTRs for the growth and differentiation of the pancreas as well as other organs. 相似文献85.
Milos Kesek MD PhD Anders Englund MD PhD Steen M. Jensen MD PhD Mats Jensen-Urstad MD PhD 《Heart rhythm》2007,4(1):17-19
BACKGROUND: Ablation procedures in the left atrium for treatment of atrial fibrillation are becoming increasingly common. The procedure often involves placing one or two circular mapping catheters in the left atrium. Entrapment of an ablation catheter in the mitral valve during ablations of left-sided accessory pathways by the retrograde approach has been described in two earlier published reports. More recently, several reports describe similar entrapment of a mapping catheter. In a recently published review, however, only one case of unspecified valve damage was registered among 8745 atrial fibrillation procedures. OBJECTIVE: The purpose of this study was to evaluate patients with entrapment. METHODS: Retrospective analysis of electrophysiological results. RESULTS: We describe three patients with entrapment during ablations for atrial fibrillation. The entrapments occurred with three different operators at three different electrophysiological laboratories within 2 years. The complication described here may be more common than is widely appreciated. CONCLUSIONS: From our figures, we estimate the incidence of the complication to 0.9% (95% confidence interval, 0.2-2.5%). 相似文献
86.
87.
Carl-Johan Boraxbekk Andreas Stomby Mats Ryberg Bernt Lindahl Christel Larsson Lars Nyberg Tommy Olsson 《Obesity facts》2015,8(4):261-272
ObjectiveIt has been suggested that overweight is negatively associated with cognitive functions. The aim of this study was to investigate whether a reduction in body weight by dietary interventions could improve episodic memory performance and alter associated functional brain responses in overweight and obese women.Methods20 overweight postmenopausal women were randomized to either a modified paleolithic diet or a standard diet adhering to the Nordic Nutrition Recommendations for 6 months. We used functional magnetic resonance imaging to examine brain function during an episodic memory task as well as anthropometric and biochemical data before and after the interventions.ResultsEpisodic memory performance improved significantly (p = 0.010) after the dietary interventions. Concomitantly, brain activity increased in the anterior part of the right hippocampus during memory encoding, without differences between diets. This was associated with decreased levels of plasma free fatty acids (FFA). Brain activity increased in pre-frontal cortex and superior/middle temporal gyri. The magnitude of increase correlated with waist circumference reduction. During episodic retrieval, brain activity decreased in inferior and middle frontal gyri, and increased in middle/superior temporal gyri.ConclusionsDiet-induced weight loss, associated with decreased levels of plasma FFA, improves episodic memory linked to increased hippocampal activity.Key Words: Functional magnetic resonance imaging, Episodic memory, Obesity, Diet interventions, Hippocampus 相似文献
88.
89.
Maria Benito de Valle Tobias Müller Einar Björnsson Morgane Otten Martin Volkmann Olaf Guckelberger Bertram Wiedenmann Riadh Sadik Eckart Schott Mats Andersson Thomas Berg Björn Lindkvist 《Digestive and liver disease》2014,46(10):903-908
Background
Elevated IgG4 levels have been reported among patients with primary sclerosing cholangitis. Epidemiological data has only been provided from tertiary centres.Aims
To investigate the prevalence of elevated IgG4 levels and to compare prognosis between patients with and without elevated IgG4 levels in serum in two European cohorts of patients with primary sclerosing cholangitis.Methods
Serum IgG4-levels were measured in a consecutive series of patients from Berlin, and retrospectively collected in a population-based cohort from Sweden (total N = 345). Cox's proportional hazard analysis was used to calculate relative risks for liver-related death or liver transplantation and cholangiocarcinoma.Results
Elevated IgG4 values were demonstrated in 10% of patients. A previous history of pancreatitis, combined intra- and extrahepatic biliary involvement and jaundice were independently associated with elevated IgG4 in multivariate analysis. IgG4 status was not associated with an increased risk for the combined endpoint liver-related death or liver transplantation or cholangiocarcinoma.Conclusion
The prevalence of elevated IgG4 values among European patients with primary sclerosing cholangitis is similar to what previously has been reported from the United States. Elevated IgG4 was not associated with an increased risk of liver transplantation or liver-related death or cholangiocarcinoma. 相似文献90.
Jennifer Viberg Mats G Hansson Sophie Langenski?ld P?r Segerdahl 《European journal of human genetics : EJHG》2014,22(4):437-441
Incidental findings (IFs) are acknowledged to be among the most important ethical issues to consider in biobank research. Genome-wide association studies and disease-specific genetic research might reveal information about individual participants that are not related to the research purpose, but may be relevant to those participants'' future health. In this article, we provide a synopsis of arguments for and against the disclosure of IFs in biobank research. We argue that arguments that do not distinguish between communications about pathogenic conditions and complex genetic risk for diseases fail, as preferences and decisions may be far more complex in the latter case. The principle of beneficence, for example, often supports the communication of incidentally discovered diseases, but if communication of risk is different, the beneficence of such communication is not equally evident. By conflating the latter form of communication with the former, the application of ethical principles to IFs in biobank research sometimes becomes too easy and frictionless. Current empirical surveys of people''s desire to be informed about IFs do not provide sufficient guidance because they rely on the same notion of risk communication as a form of communication about actual health and disease. Differently designed empirical research and more reflection on biobank research and genetic risk information is required before ethical principles can be applied to support the adoption of a reasonable and comprehensive policy for handling IFs.A much discussed problem associated with biobank research is the return to participants of incidental findings (IFs): ‘a finding concerning an individual research participant that has a potential health or reproductive importance and is discovered in the course of conducting research but is beyond the aims of the study.''1 How should such information be handled ethically responsibly in genome-wide association studies and disease-specific genetic research?In this paper, we argue that the discussion up until now has neglected a distinction that should be held in the forefront of the discussion, especially concerning genetic biobank research: the distinction between an incidentally discovered disease and an incidentally discovered increased genetic risk for disease of unclear predictive value. Biobank research and rapidly increasing studies in genomics, proteomics, and nutrigenomics continue to identify many genes and biomarkers associated with risk of disease. Genetic testing for monogenic disorders are well established in health services, but little is yet known of the best way to handle complex risk information associated with multifactorial disorders in which the predictive importance of individual elements – genetic, epigenetic, or environmental – will differ for different individuals. The value of being informed about an incidentally discovered genetic risk (be it inherited or caused by a virus) is therefore much more difficult to ascertain than that for an incidentally discovered pathogenic condition revealed, for example, in a brain imaging study.The aim of this paper is to exhibit the absence of a distinction between disease and complex genetic risk for disease in the discussion, and to show how the arguments therefore fail to address the more complex kinds of IFs that increasingly arise in biobank research. Further research should be conducted before the arguments can be considered conclusive.Disease risks can be discovered also in imaging studies, of course, a blood vessel with thin walls can imply an increased risk for stroke. Our focus in this paper, however, is on genetic biobank research, where IFs increasingly concern multifactorial risks for disease having both genetic and environmental dimensions, which we believe introduce complications that so far have not been addressed. 相似文献