全文获取类型
收费全文 | 483616篇 |
免费 | 35447篇 |
国内免费 | 12023篇 |
专业分类
耳鼻咽喉 | 9030篇 |
儿科学 | 12324篇 |
妇产科学 | 7584篇 |
基础医学 | 33440篇 |
口腔科学 | 13594篇 |
临床医学 | 51687篇 |
内科学 | 61879篇 |
皮肤病学 | 5812篇 |
神经病学 | 22652篇 |
特种医学 | 18641篇 |
外国民族医学 | 52篇 |
外科学 | 78244篇 |
综合类 | 62679篇 |
现状与发展 | 37篇 |
一般理论 | 26篇 |
预防医学 | 42597篇 |
眼科学 | 10607篇 |
药学 | 44598篇 |
552篇 | |
中国医学 | 30504篇 |
肿瘤学 | 24547篇 |
出版年
2023年 | 7449篇 |
2022年 | 11676篇 |
2021年 | 21558篇 |
2020年 | 18550篇 |
2019年 | 22601篇 |
2018年 | 17668篇 |
2017年 | 15811篇 |
2016年 | 17103篇 |
2015年 | 19391篇 |
2014年 | 36491篇 |
2013年 | 34367篇 |
2012年 | 34834篇 |
2011年 | 32769篇 |
2010年 | 28405篇 |
2009年 | 26340篇 |
2008年 | 24091篇 |
2007年 | 24265篇 |
2006年 | 20762篇 |
2005年 | 15713篇 |
2004年 | 10907篇 |
2003年 | 9390篇 |
2002年 | 7383篇 |
2001年 | 6259篇 |
2000年 | 5566篇 |
1999年 | 4259篇 |
1998年 | 3922篇 |
1997年 | 3551篇 |
1996年 | 2870篇 |
1995年 | 2896篇 |
1994年 | 2668篇 |
1993年 | 2210篇 |
1992年 | 2288篇 |
1991年 | 2080篇 |
1990年 | 1868篇 |
1989年 | 1861篇 |
1988年 | 1713篇 |
1987年 | 1562篇 |
1986年 | 1336篇 |
1985年 | 3305篇 |
1984年 | 3693篇 |
1983年 | 2487篇 |
1982年 | 2977篇 |
1981年 | 2447篇 |
1980年 | 2123篇 |
1979年 | 1833篇 |
1978年 | 1477篇 |
1977年 | 1290篇 |
1976年 | 1300篇 |
1975年 | 898篇 |
1974年 | 819篇 |
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
61.
《Vaccine》2022,40(6):904-911
BackgroundGSK initiated a Pregnancy Registry in the United States (US) for the reduced-antigen-content tetanus-diphtheria-acellular pertussis (Tdap; Boostrix, GSK) vaccine with the aim to detect and describe pregnancy outcomes in women vaccinated with Boostrix 28 days before estimated conception or during pregnancy.MethodsVoluntary reports of pregnancy exposure to Boostrix received from spontaneous and post-marketing surveillance sources in the US were assessed. Reports were classified as prospective or retrospective based on the knowledge of pregnancy outcomes at the time of reporting. For completeness, reports of exposure to Boostrix or to the Tdap-inactivated poliovirus vaccine (Boostrix-IPV, GSK) reported to the global safety database from countries outside the US were also evaluated.ResultsFrom May 2005 to August 2019, 1517 (1455 prospective and 62 retrospective) pregnancy reports were received in the Boostrix US Pregnancy Registry. Of the prospective reports, 250 had known outcomes: 244 live infants with no apparent birth defects (BDs), three live infants with BDs, and three spontaneous abortions with no apparent BDs. Of the retrospective reports, 55 had known outcomes: 33 live infants with no apparent BDs, 16 live infants with BDs, one spontaneous abortion with no apparent BDs, four stillbirths with no apparent BDs, and one stillbirth with BDs. Cumulatively, 1321 pregnancy reports (1006 for Boostrix; 315 for Boostrix-IPV) were received from countries outside the US. Of these, 163 prospective reports and 551 retrospective reports had known outcomes. Results were in line with those from the Boostrix US Pregnancy Registry.ConclusionsData currently available from the Boostrix US Pregnancy Registry and from countries outside the US suggested that exposure to Boostrix or Boostrix-IPV during pregnancy does not raise safety concerns related to adverse pregnancy outcomes or BDs. 相似文献
62.
63.
64.
《Vaccine》2022,40(16):2370-2378
Porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) are two of the most common pathogens involved in the porcine respiratory disease complex (PRDC) resulting in significant economic losses worldwide. Vaccination is the most effective approach to disease prevention. Since PRRSV and Mhp co-infections are very common, an efficient dual vaccine against these pathogens is required for the global swine industry. Compared with traditional vaccines, multi-epitope vaccines have several advantages, they are comparatively easy to produce and construct, are chemically stable, and do not have an infectious potential. In this study, to develop a safe and effective vaccine, B cell and T cell epitopes of PRRSV-GP5, PRRSV-M, Mhp-P46, and Mhp-P65 protein had been screened to construct a recombinant epitope protein rEP-PM that has good hydrophilicity, strong antigenicity, and high surface accessibility, and each epitope is independent and complete. After immunization in mice, rEP-PM could induce the production of high levels of antibodies, and it had good immunoreactivity with anti-rEP-PM, anti-PRRSV, and anti-Mhp antibodies. The anti-rEP-PM antibody specifically recognizes proteins from PRRSV and Mhp. Moreover, rEP-PM induced a Th1-dominant cellular immune response in mice. Our results showed that the rEP-PM protein could be a potential candidate for the development of a safe and effective multi-epitope peptide combined vaccine to control PRRSV and Mhp infections. 相似文献
65.
《Vaccine》2022,40(33):4748-4763
This work identifies the innovations that made it possible for the Bio-Manguinhos/Fiocruz Immunobiological Technology Institute to engage in the entire production of the Oxford/AstraZeneca vaccine (ChAdOx1 nCov-19) in Brazil, just 1.8 years after the COVID-19 pandemic was declared. The results were summarized in a case-based innovation model composed of 11 workstreams, 32 stages, 22 gates, 11 innovations, and 38 events. In terms of research contributions, three were found: (i) the identification of firm and government-level innovations allowing the substantial reduction in the COVID-19 vaccine time-to-market in Brazil; (ii) the presentation of empirical evidence supporting the new Outbreak Paradigm for vaccine research, development, and production; and (iii) the proposition of a conceptual model for describing innovations through the vaccine value chain in pandemic contexts, particularly when technology transfer is involved. 相似文献
66.
67.
《Cirugía espa?ola》2022,100(11):709-717
ObjectiveMost evidence, including recent randomized controlled trials, analysing anal squamous cell carcinoma (SCC) do not consider immunocompromise patient population. The aim of this study was to compare clinical and oncological outcomes among immunocompetent and immunocompromised patients with anal squamous cell carcinoma.MethodMulticentric retrospective comparative study including 2 cohorts of consecutive patients, immunocompetent and immunocompromised, diagnosed with anal SCC. This study evaluated clinical characteristics, clinical response to radical chemoradiotherapy (CRT) and long-term oncological results including both local and distant recurrence, overall survival (OS) and disease-free survival (DFS).ResultsA total of 84 patients, 47 (55.6%) female, diagnosed with anal SCC from January 2012 to December 2017 were included, 22 (26%) and 62 (74%) patients in immunocompromised and immunocompetent groups respectively. Patients in immunocompromised group were significantly younger (53 vs. 61 years; P=0.001), with smaller tumoral size (P=0.044) and reported higher rates of substance abuse.including tobacco use (P=0.034) and parenteral drug consumption (P=0.001). No differences were found in administered therapies (P=301) neither in clinical response to chemoradiotherapy (83 vs. 100%). Moreover, similar 5-year OS (60 vs. 64%; P=0.756) and DFS (65 vs. 68%; P=0.338) were observed.ConclusionThe present study shows no significant differences in long-term oncological results among immunocompetent and immunocompromised patients diagnosed with anal SCC, with a similar oncologic treatment. This evidence might be explained due to the close monitoring and adequate therapeutic control of HIV positive patients. 相似文献
68.
69.
《European journal of surgical oncology》2022,48(6):1264-1271
BackgroundIn order to avoid excessive treatment of thyroid nodules in the clinic, it is necessary to find a simple and practical analysis method to comprehensively and accurately reflect benign or malignant thyroid nodules. This study aimed to construct and validate a comprehensive and reliable network-based predictive model using a variety of imaging and laboratory criteria for thyroid nodules to stratify the risk of malignancy prior to surgery.MethodsWe retrospectively analyzed data from patients who underwent surgical treatment for thyroid nodules at the Thyroid and Breast Diagnosis and Treatment Center of Weifang Hospital of Traditional Chinese Medicine between January 2018 and December 2020. Binary logical regression analysis was performed to predict whether nodules were malignant or benign. The developmental dataset included 457 patients (January 2018–December 2020). The validation set included separate data points (n = 225, January 2018–December 2020).ResultsIn this study, criteria that showed significant predictive value for malignant nodules included TI-RADS: 4b (p = 0.065); Bethesda IV, Bethesda V, Bethesda VI (P < 0.0001); BRAFV600E mutation (P < 0.0001); Calcitonin>5 pg/ml (p = 0.0037); and FNA-Tg>30 ng/ml (p = 0.0003). A 10-grade risk scoring system was developed. The risk of malignancy risk ranged from 2.06% to 100% and was positively associated with increasing risk grade. The areas under the receiver-operating characteristic curve of the development and validation sets were 0.972 and 0.946, respectively.ConclusionA simple, comprehensive and reliable web-based predictive model was designed using a variety of imaging and laboratory criteria to stratify thyroid nodules by probability of malignancy. 相似文献
70.
《Revista brasileira de otorrinolaringologia (English ed.)》2022,88(4):602-606
IntroductionThe Modena bleeding score is a categorical rating scale that allows the assessment of the surgical field in relation to bleeding during endoscopic surgery. It has recently been presented and validated in the field of endoscopic ear surgery by the present authors. The Modena bleeding score provides five grades for rating the surgical field during endoscopic procedures (from grade 1 ? no bleeding to grade 5 ? bleeding that prevents every surgical procedure except those dedicated to bleeding control).ObjectiveThe aim of this study was to validate the Modena bleeding score in the setting of endoscopic sinus surgery.MethodsFifteen three-minute videos of endoscopic sinus surgery procedures (each containing three bleeding situations) were evaluated by 15 specialists, using the Modena bleeding score. Intra and inter-rater reliability were assessed, and the clinical validity of the Modena bleeding score was calculated using a referent standard.ResultsThe data analysis showed an intra-rater reliability ranging from 0.6336 to 0.861. The inter-rater reliability ranged from 0.676 to 0.844. The clinical validity was α = 0.70; confidence limits: 0.64 ? 0.75, corresponding to substantial agreement.ConclusionThe Modena bleeding score is an effective method to score bleeding during endoscopic sinus surgery. Its application in future research could facilitate the performance and efficacy assessment of surgical techniques, materials or devices aimed to bleeding control during endoscopic sinus surgery. 相似文献