全文获取类型
收费全文 | 1839篇 |
免费 | 106篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 43篇 |
妇产科学 | 149篇 |
基础医学 | 221篇 |
口腔科学 | 45篇 |
临床医学 | 132篇 |
内科学 | 300篇 |
皮肤病学 | 34篇 |
神经病学 | 206篇 |
特种医学 | 156篇 |
外科学 | 215篇 |
综合类 | 22篇 |
一般理论 | 1篇 |
预防医学 | 91篇 |
眼科学 | 99篇 |
药学 | 138篇 |
中国医学 | 7篇 |
肿瘤学 | 73篇 |
出版年
2024年 | 1篇 |
2023年 | 9篇 |
2022年 | 28篇 |
2021年 | 64篇 |
2020年 | 41篇 |
2019年 | 60篇 |
2018年 | 65篇 |
2017年 | 50篇 |
2016年 | 50篇 |
2015年 | 67篇 |
2014年 | 88篇 |
2013年 | 119篇 |
2012年 | 149篇 |
2011年 | 170篇 |
2010年 | 89篇 |
2009年 | 79篇 |
2008年 | 133篇 |
2007年 | 151篇 |
2006年 | 114篇 |
2005年 | 109篇 |
2004年 | 92篇 |
2003年 | 83篇 |
2002年 | 48篇 |
2001年 | 19篇 |
2000年 | 14篇 |
1999年 | 11篇 |
1998年 | 7篇 |
1997年 | 7篇 |
1996年 | 1篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 4篇 |
1973年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有1956条查询结果,搜索用时 31 毫秒
41.
A new type of polymer-layered double hydroxide nanocomposite bearing thiazole moieties was used to support CuI nanoparticles (NPs) as a heterogeneous catalyst for the synthesis of bis-N-arylsulfonamides. The prepared nanostructured catalyst (LDH@MPS-GMA-TZ-CuI) showed high catalytic activity, as well as excellent recyclability for the preparation of bis-N-arylsulfonamides via the chemoselective reaction of 1,3-disulfonyl chloride and nitroarenes. The superior catalytic activity of the LDH@MPS-GMA-TZ-CuI is related to the high loading of CuI NPs and favorable surface properties.CuI NPs supported on novel polymer–LDHs nanocomposite was investigated for the synthesis of bis-N-arylsulfonamides. 相似文献
42.
In this work, an outstanding nano-structured composite electrode is fabricated through the co-deposition of Co(OH)2 nanoplates and porous reduced GO (p-rGO) nanosheets onto Ni foam (NF). Through field emission scanning electron microscopy and transmission electron microscopy observations, it was confirmed that porous reduced graphene oxide sheets are completely wrapped by uniform hexagonal Co(OH)2 plates. Due to the unique architecture of both components of the prepared composite, a high surface area of 234.7 m2 g−1 and mean pore size of 3.65 nm were observed for the Co(OH)2@p-rGO composite. The constructed Co(OH)2@p-rGO/NF composite electrode shows higher energy storage capability compared to that of Co(OH)2/NF and p-rGO/NF electrodes. The Co(OH)2/NF electrode shows specific capacitances of 902 and 311 F g–1 at 5 and 30 A g–1, while the Co(OH)2@p-rGO/NF electrode delivers 1688 and 1355 F g–1 under the same current loads, respectively. Furthermore, when the current load was increased from 1 to 30 A g–1, 74.5% capacitance retention was observed for the Co(OH)2@p-rGO/NF electrode, indicating its outstanding high-power capability, while the Co(OH)2/NF electrode retained only 38.5% of its initial capacitance. The fabricated Co(OH)2@p-rGO/NF//rGO/NF ASC device shows an areal capacitance of 3.29 F cm−2, cycling retention of 91.2% after 4500 cycles at 5 A g−1 and energy density of 68.7 W h kg−1 at a power density of 895 W kg−1. The results of electrochemical tests prove that Co(OH)2@p-rGO/NF exhibits good performance as a positive electrode for use in an asymmetric supercapacitor device. The prepared porous composite electrode is thus a promising candidate for use in supercapacitor applications.Fabrication mechanism of a ready-to-use Co(OH)2@p-rGO/NF electrode: (a) base generation step, (b) electrophoretic deposition of rGO onto NF and (c) chemical formation of Co(OH)2 on rGO. 相似文献
43.
44.
Hedaiat Moradpoor Fatemeh Salari Ramin Mosharraf Sahar Raissi Mohammadjavad Shirani 《Journal of oral rehabilitation》2020,47(4):494-500
Occlusal scheme is a controversial topic that has been linked to patient satisfaction with conventional complete dentures (CCDs). This study aimed to compare the patient satisfaction with CCDs with four different occlusal schemes namely the lingualised occlusion (LO), buccalised occlusion (BO), fully bilateral balanced occlusion (FBBO) and partially group function occlusion (PGFO). In this clinical study, new CCDs were made for 121 patients; out of which, 97 patients (mean age of 57.87 ± 9.5 years) completed the 1-year follow-up. The CCD wearers were followed up at 1 month, 3 months and 1 year after CCD delivery. Data were collected via an interview and recorded in a checklist by a blinded examiner. The checklist included the demographic variables, the 19-item version of Oral Health Impact Profile for Edentulous Patients (OHIP-EDENT), and seven 100-mm line visual analogue scales (VASs) to assess the items related to patient satisfaction. The Kruskal-Wallis and Friedman tests followed by post hoc tests were used to compare the variables among the 4 groups and between the 3 follow-ups. P-value ≤ .05 was considered statistically significant for all tests. The patients with BO presented higher satisfaction scores for comfort, stability and retention at the 1-year follow-up compared with PGFO. Both PGFO and FBBO groups had higher physical pain scores compared with BO and LO. The psychological discomfort scores of FBBO group were significantly higher than those in LO group. Pairwise comparisons revealed no significant differences in the general patient satisfaction and total OHIP-EDENT scores between the 4 groups. For most items, within-group analysis showed significant improvement of the satisfaction scores and reduction of domain scores over time. 相似文献
45.
46.
Rasoul Pourebrahim Hossein Fakhrzadeh Fatemeh Bandarian Ozra Tabatabaie Masoomeh Noori Forouzan Djalilpour Farzaneh Zahedi Iman Rahimi Ramin Heshmat Ebrahim Djavadi Sara Ghotbi Bagher Larijani 《European journal of cardiovascular prevention and rehabilitation》2006,13(2):229-235
BACKGROUND: A parental history of cardiovascular disease has a strong relationship with risk factor clusters in the offspring. This study was performed to identify major cardiovascular risk factors in middle school-aged children and their parents in both high and low-risk families. DESIGN: A school-based, cross-sectional study. METHODS: The middle schools of the 6th district of Tehran were divided randomly into two groups. A total of 169 high-risk children with their families were recruited from the first group and 105 low-risk children with their families were recruited from the second group of schools. Anthropometric and metabolic measurements were performed. RESULTS: The means of the waist circumference and waist-to-hip ratio were significantly higher in high-risk fathers. The means of total and low-density lipoprotein (LDL) cholesterol were significantly higher in both parents and children of the high-risk group. The means of the fasting plasma glucose were significantly higher in fathers and offspring of high-risk families. More fathers in high-risk families were smokers. The prevalence of increased total cholesterol, LDL-cholesterol and hyperglycemia (> or = 100 mg/dl) were higher in high-risk parents and children. The prevalence of increased body mass index (> or = 25 kg/m for parents and 85th percentile for children) was higher in fathers and children of high-risk families. CONCLUSIONS: Cardiovascular risk factors are more prevalent and clustered in high-risk families. The screening of high-risk families is essential to prevent the progression of atherosclerosis from childhood and reduce the burden of cardiovascular disease in adulthood. 相似文献
47.
Ramin Khatami Gianina Luca Christian R. Baumann Claudio L. Bassetti Oliviero Bruni Francesca Canellas Yves Dauvilliers Rafael Del Rio‐Villegas Eva Feketeova Raffaele Ferri Peter Geisler Birgit Högl Poul Jennum Birgitte R. Kornum Michel Lecendreux Antonio Martins‐da‐Silva Johannes Mathis Geert Mayer Teresa Paiva Markku Partinen Rosa Peraita‐Adrados Guiseppe Plazzi Joan Santamaria Karel Sonka Renata Riha Mehdi Tafti Aleksandra Wierzbicka Peter Young Gert Jan Lammers Sebastiaan Overeem European Narcolepsy Network 《Journal of sleep research》2016,25(3):356-364
Narcolepsy with cataplexy is a rare disease with an estimated prevalence of 0.02% in European populations. Narcolepsy shares many features of rare disorders, in particular the lack of awareness of the disease with serious consequences for healthcare supply. Similar to other rare diseases, only a few European countries have registered narcolepsy cases in databases of the International Classification of Diseases or in registries of the European health authorities. A promising approach to identify disease‐specific adverse health effects and needs in healthcare delivery in the field of rare diseases is to establish a distributed expert network. A first and important step is to create a database that allows collection, storage and dissemination of data on narcolepsy in a comprehensive and systematic way. Here, the first prospective web‐based European narcolepsy database hosted by the European Narcolepsy Network is introduced. The database structure, standardization of data acquisition and quality control procedures are described, and an overview provided of the first 1079 patients from 18 European specialized centres. Due to its standardization this continuously increasing data pool is most promising to provide a better insight into many unsolved aspects of narcolepsy and related disorders, including clear phenotype characterization of subtypes of narcolepsy, more precise epidemiological data and knowledge on the natural history of narcolepsy, expectations about treatment effects, identification of post‐marketing medication side‐effects, and will contribute to improve clinical trial designs and provide facilities to further develop phase III trials. 相似文献
48.
Vahid Haghpanah Peiman Shooshtarizadeh Ramin Heshmat Bagher Larijani Seyed Mohamad Tavangar 《Applied immunohistochemistry & molecular morphology》2006,14(4):422-425
Survivin is one of the 8 members of human inhibitor of apoptosis , which is differentially expressed in cancerous/transformed cells versus normal differentiated tissues. This retrospective study of thyroid histologic samples aimed to assess the clinical usefulness of survivin immunostaining for discrimination between follicular adenoma and carcinoma of thyroid. Immunohistochemical staining for survivin was performed on 41 lesions from patients who had undergone surgery for either follicular adenoma or carcinoma of thyroid. Survivin expression was significantly (P < 0.005) higher in the cases that received a diagnosis of carcinoma in comparison with follicular adenomas cases. Odds ratio of follicular carcinoma for survivin expression was 21.375 (95% CI: 3.283 to 139.177). Our results showed potential value of survivin in discrimination between follicular thyroid adenoma and follicular thyroid carcinoma. We conclude that survivin is a potential candidate for further investigation in the proper histologic diagnosis of thyroid cancers. 相似文献
49.
Anurag Gupta Ronilda Lacson Patricia C. Balthazar Shan Haq Adam B. Landman Ramin Khorasani 《Journal of digital imaging》2018,31(4):562-567
To facilitate follow-up of critical test results across transitions in patient care settings, we implemented an electronic discharge module that enabled care providers to include follow-up recommendations in the discharge instructions. We assessed the impact of this module on documentation of follow-up recommendations for critical imaging findings in Emergency Department (ED) discharge instructions. We studied 240 patients with critical imaging findings discharged from the ED before (n?=?80) and after (n?=?160) implementation of the module. We manually reviewed hand-written forms and electronic discharge instructions to determine if follow-up recommendations were documented. Follow-up recommendations in ED discharge instructions increased from 60.0% (48/80) to 73.8% (118/160) post-module implementation (p?=?0.03), a relative increase of 23%. There was no significant change in the rate of documented critical imaging findings in the discharge instructions (77.5% [62/80] before the intervention and 76.9% [123/160] after the intervention; p?=?0.91). Implementation of a discharge module was associated with increased documentation of critical imaging finding follow-up recommendations in ED discharge instructions. However, one in four patients still did not receive adequate follow-up recommendations, suggesting further opportunities for performance improvement exist. 相似文献
50.
Aguilera M Ramin K Nyholm J Gidvani M Jacobs K Sivanandam S 《American journal of perinatology》2011,28(6):431-434
The etiology of polyhydramnios may be attributed to either increased production of amniotic fluid (fetal polyuria or high-output cardiac failure) or decreased fetal swallowing (obstruction or neurological impairment). Although idiopathic polyhydramnios occurs in nearly half of all cases, it is often associated with fetal abnormalities. Fetal ductus arteriosus flow is normally from right to left. We report a case of antenatally detected bidirectional fetal ductus arteriosus flow diagnosed concomitantly with polyhydramnios. Amnioreduction was performed due to severe maternal symptoms, which resulted in correction of the fetal ductus arteriosus flow. Postnatal diagnosis of a Morgagni diaphragmatic hernia indicates that our sonographic findings collectively may have been a diagnostic clue. 相似文献