全文获取类型
收费全文 | 20987篇 |
免费 | 6228篇 |
国内免费 | 95篇 |
专业分类
耳鼻咽喉 | 411篇 |
儿科学 | 501篇 |
妇产科学 | 556篇 |
基础医学 | 660篇 |
口腔科学 | 1466篇 |
临床医学 | 6420篇 |
内科学 | 5040篇 |
皮肤病学 | 662篇 |
神经病学 | 2463篇 |
特种医学 | 652篇 |
外科学 | 2986篇 |
综合类 | 138篇 |
现状与发展 | 2篇 |
一般理论 | 1篇 |
预防医学 | 2744篇 |
眼科学 | 446篇 |
药学 | 471篇 |
中国医学 | 56篇 |
肿瘤学 | 1635篇 |
出版年
2024年 | 225篇 |
2023年 | 1365篇 |
2022年 | 492篇 |
2021年 | 965篇 |
2020年 | 1315篇 |
2019年 | 693篇 |
2018年 | 1748篇 |
2017年 | 1806篇 |
2016年 | 1765篇 |
2015年 | 1789篇 |
2014年 | 2077篇 |
2013年 | 2070篇 |
2012年 | 994篇 |
2011年 | 958篇 |
2010年 | 1252篇 |
2009年 | 1558篇 |
2008年 | 725篇 |
2007年 | 535篇 |
2006年 | 638篇 |
2005年 | 408篇 |
2004年 | 338篇 |
2003年 | 292篇 |
2002年 | 257篇 |
2001年 | 299篇 |
2000年 | 154篇 |
1999年 | 249篇 |
1998年 | 290篇 |
1997年 | 304篇 |
1996年 | 295篇 |
1995年 | 261篇 |
1994年 | 165篇 |
1993年 | 156篇 |
1992年 | 117篇 |
1991年 | 93篇 |
1990年 | 80篇 |
1989年 | 100篇 |
1988年 | 79篇 |
1987年 | 59篇 |
1986年 | 49篇 |
1985年 | 56篇 |
1984年 | 43篇 |
1983年 | 26篇 |
1982年 | 25篇 |
1981年 | 24篇 |
1980年 | 15篇 |
1978年 | 17篇 |
1977年 | 15篇 |
1976年 | 10篇 |
1975年 | 10篇 |
1971年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 17 毫秒
131.
132.
Saqib Masroor Qiong Qiu Mohamad Alghothani Rajesh Gupta George V. Moukarbel 《Journal of cardiac surgery》2021,36(1):398-400
Percutaneous occlusion of the left atrial appendage is increasingly being used as an alternative for stroke prevention in patients with non‐valvular atrial fibrillation at high risk of complications from long term anticoagulation. We describe a case of left atrial appendage perforation during Watchman device implantation requiring emergency repair of the left atrium using sternotomy and cardiopulmonary bypass. Technical considerations for surgical decision making are discussed; in hemodynamically unstable patients as well as those at high risk for embolization. 相似文献
133.
Khodamorad Jamshidi Abolfazl Bagherifard Hamadalla Hadi Al-Baseesee Alireza Mirzaei 《Clinical orthopaedics and related research》2021,479(5):1134
BackgroundHeterotopic ossification (HO) is common after total joint arthroplasty and usually does not cause diagnostic problems. However, the occurrence of HO after oncologic prostheses implantation can be troublesome as it may mimic a locally recurrent tumor. Because this distinction could have a profound impact on the surgeon and patient, it is important to distinguish the two entities; to our knowledge, no study has evaluated this after oncologic endoprosthetic reconstruction around the knee after tumor resection.Questions/purposes(1) How common is the occurrence of HO compared with local recurrence (LR) after resection of bone sarcoma and the use of an oncologic knee prosthesis? (2) Are there any factors associated with the development of HO after limb salvage procedures with an endoprosthesis? (3) What features allow the surgeon to differentiate HO from a locally recurrent tumor in this setting?MethodsBetween 2002 and 2018, we performed 409 resections of primary bone tumors followed by reconstructions with oncologic endoprostheses. Of these, 17% (71 of 409) died before 2 years and did not have HO at that time, 2% (8 of 409) were lost to follow-up before 2 years, and another 2% (10 of 409) did not have radiographs available at a minimum of 2 years after surgery (and had not developed HO before then), and so could not be analyzed, leaving 320 patients for analysis in this retrospective study. Forty-two patients were excluded; 2% (5 of 320) for a history of failed allograft reconstruction, 3% (8 of 320) for pathologic fracture at presentation, 2% (6 of 320) for inadequate or complicated biopsy, 1% (2 of 320) for stem fractures, 2% (7 of 320) for stem loosening, and 4% (14 of 320) for extracortical bone bridging, leaving 278 patients for final evaluation. Two observers analyzed AP and lateral radiographs for signs of HO at a mean follow-up of 63 ± 33 months after surgery. We defined HO as extraskeletal bone formation in soft tissues. The primary study endpoint was survivorship free from HO, as ascertained by a competing-risks estimator. To identify factors associated with HO appearance, the demographic, radiographic, clinical, pathologic, and surgical characteristics were compared between patients with HO and those who had no lesion. Characteristic features were also compared between patients with HO and those with LR to help their differentiation. Univariate analysis was used for all statistical evaluations.ResultsHO developed in 8% (21 of 278) of patients in whom oncologic knee prosthesis was implanted. LR developed in 10% (28 of 278) of the patients. According to survivorship estimates, the HO-free survival rate was not different from the LR-free survival rate at 2 years after oncologic knee reconstruction (76 ± 5% [95% CI 63 to 87] versus 74 ± 5% [95% CI 62 to 88]; p = 0.19). History of infection was more common in patients with HO than in patients with no lesion (19% [4 of 21] versus 5% [12 of 229], Odds ratio [OR] 6 [95% CI 2 to 17]; p < 0.001). The male sex was more common in the HO group as well (76% [16 of 21] versus 55% [128 of 229], OR 2 [95% CI 1 to 5]; p = 0.03). The Modular Universal Tumor and Revision System prosthesis was more frequently used in patients with HO (67% [14 of 21]) compared to those with no lesions (40% [92 of 229]; OR 2 [95% CI 1 to 5]; p = 0.02). The lesion border in radiographs was ill-defined in 19% (4 of 21) of patients with HO and 100% (28 of 28) of patients with LR (OR 8 [95% CI 3 to 20]; p < 0.001). The median time to the appearance of HO was shorter than the time to LR (8 months [3 to 13] versus 16 months [11 to 21], [95% CI 10 to 13]; p < 0.001). Pain at presentation was more frequent in patients with LR than in those with HO (86% [24 of 28] versus 14% [3 of 21], OR 36 [95% CI 7 to 181]; p < 0.001).ConclusionHO may occur after the use of oncologic knee prostheses for reconstruction after tumor resection. In most patients, HO could be differentiated from local recurrence through identifying a well-defined border on radiographs. Otherwise, factors such as an earlier time of presentation and absence of pain could suggest an HO, rather than an LR.Level of EvidenceLevel III, therapeutic study. 相似文献
134.
Mohamad Kassem Ali El Habhab Guillaume Kreutter Lamia Amoura Philippe Baltzinger Malak Abbas Noura Sbat Fatiha Zobairi Valérie B. Schini-Kerth Laurence Kessler Florence Toti 《Transplantation proceedings》2021,53(5):1736-1743
BackgroundIschemia-driven islet isolation procedure is one of the limiting causes of pancreatic islet transplantation. Ischemia-reperfusion process is associated with endothelium dysfunction and the release of pro-senescent microvesicles. We investigated whether pro-senescent endothelial microvesicles prompt islet senescence and dysfunction in vitro.Material and methodsPancreatic islets were isolated from male young rats. Replicative endothelial senescence was induced by serial passaging of primary porcine coronary artery endothelial cells, and microvesicles were isolated either from young passage 1 (P1) or senescent passage 3 (P3) endothelial cells. Islet viability was assessed by fluorescence microscopy, apoptosis by flow cytometry, and Western blot. Function was assessed by insulin secretion and islet senescence markers p53, p21, and p16 by Western blot. Microvesicles were stained by the PKH26 lipid fluorescent probe and their islet integration assessed by microscopy and flow cytometry.ResultsRegardless of the passage, half microvesicles were integrated in target islets after 24 hours incubation. Insulin secretion significantly decreased after treatment by senescent microvesicles (P3: 1.7 ± 0.2 vs untreated islet: 2.7 ± 0.2, P < .05) without altering the islet viability (89.47% ± 1.69 vs 93.15% ± 0.97) and with no significant apoptosis. Senescent microvesicles significantly doubled the expression of p53, p21, and p16 (P < .05), whereas young microvesicles had no significant effect.ConclusionPro-senescent endothelial microvesicles specifically accelerate the senescence of islets and alter their function. These data suggest that islet isolation contributes to endothelial driven islet senescence. 相似文献
135.
136.
137.
Gerson M. Struik MSc MD PhD Bram Schermers MSc Ingeborg Mares MSc MD PhD Harold E. Lont MSc MD Jennifer W. Bradshaw MSc MD Bernard ten Haken MSc Ir PhD Theo J. M. Ruers MSc MD PhD Jurgen E. M. Mourik PhD Erwin Birnie MSc PhD Taco M. A. L. Klem MSc MD PhD 《The breast journal》2021,27(8):638-650
Wire-guided localization (WGL) is the standard of care in the surgical treatment of nonpalpable breast tumors. In this study, we compare the use of a new magnetic marker localization (MaMaLoc) technique to WGL in the treatment of early-stage breast cancer patients. Open-label, single-center, randomized controlled trial comparing MaMaLoc (intervention) to WGL (control) in women with early-stage breast cancer. Primary outcome was surgical usability measured using the System Usability Scale (SUS, 0–100 score). Secondary outcomes were patient reported, clinical, and pathological outcomes such as retrieval rate, operative time, resected specimen weight, margin status, and reoperation rate. Thirty-two patients were analyzed in the MaMaLoc group and 35 in the WGL group. Patient and tumor characteristics were comparable between groups. No in situ complications occurred. Retrieval rate was 100% in both groups. Surgical usability was higher for MaMaLoc: 70.2 ± 8.9 vs. 58.1 ± 9.1, p < 0.001. Patients reported higher overall satisfaction with MaMaLoc (median score 5/5) versus WGL (score 4/5), p < 0.001. The use of magnetic marker localization (MaMaLoc) for early-stage breast cancer is effective and has higher surgical usability than standard WGL. 相似文献
138.
139.