全文获取类型
收费全文 | 36048篇 |
免费 | 2074篇 |
国内免费 | 721篇 |
专业分类
耳鼻咽喉 | 290篇 |
儿科学 | 190篇 |
妇产科学 | 259篇 |
基础医学 | 1697篇 |
口腔科学 | 2055篇 |
临床医学 | 2988篇 |
内科学 | 1792篇 |
皮肤病学 | 117篇 |
神经病学 | 724篇 |
特种医学 | 1952篇 |
外国民族医学 | 2篇 |
外科学 | 13926篇 |
综合类 | 6564篇 |
预防医学 | 1264篇 |
眼科学 | 253篇 |
药学 | 2180篇 |
60篇 | |
中国医学 | 1423篇 |
肿瘤学 | 1107篇 |
出版年
2024年 | 29篇 |
2023年 | 581篇 |
2022年 | 1051篇 |
2021年 | 1480篇 |
2020年 | 1669篇 |
2019年 | 1126篇 |
2018年 | 1060篇 |
2017年 | 1225篇 |
2016年 | 1400篇 |
2015年 | 1276篇 |
2014年 | 2758篇 |
2013年 | 2549篇 |
2012年 | 2515篇 |
2011年 | 2690篇 |
2010年 | 2217篇 |
2009年 | 2075篇 |
2008年 | 1884篇 |
2007年 | 1900篇 |
2006年 | 1634篇 |
2005年 | 1514篇 |
2004年 | 1228篇 |
2003年 | 918篇 |
2002年 | 694篇 |
2001年 | 605篇 |
2000年 | 486篇 |
1999年 | 422篇 |
1998年 | 320篇 |
1997年 | 282篇 |
1996年 | 207篇 |
1995年 | 165篇 |
1994年 | 139篇 |
1993年 | 120篇 |
1992年 | 85篇 |
1991年 | 67篇 |
1990年 | 44篇 |
1989年 | 38篇 |
1988年 | 41篇 |
1987年 | 37篇 |
1986年 | 33篇 |
1985年 | 37篇 |
1984年 | 23篇 |
1983年 | 36篇 |
1982年 | 43篇 |
1981年 | 35篇 |
1980年 | 19篇 |
1979年 | 19篇 |
1978年 | 17篇 |
1977年 | 11篇 |
1976年 | 14篇 |
1975年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
《Cirugía espa?ola》2023,101(8):548-554
IntroductionPelvic fractures due to high energy trauma present a high risk of associated injuries that compromise the functional and vital prognosis of the patients. The objective of this study was to analyze the relationship between traumatic pelvic fractures and their associated injuries according to the Tile classification.MethodsRetrospective observational study of patients who suffered traumatic pelvic fractures (Type A, B or C of the Tile classification) with concomitant associated injuries, analyzing hemoglobin levels, between 6/2013 and 1/2016.ResultsA total of 42 patients were included; of those 69% (n = 29) were males, mean age was 48 years. 45% (n = 19) suffered traffic accidents and 26.2% (n = 11) falls. There was a different proportion in pelvic injuries: Tile A (n = 15, 35.7%), B (n = 20, 47.6%), and C (n = 7, 16.6%) of cases. 54.8% (n = 23) underwent surgery, 21.4% (n = 9) needed temporary or definitive external fixation. Significant differences were found between Tile A type and scapula fractures (P=.032), and Tile B with sacral fractures (P=.033) and visceral injuries (P=.049), while there is a tendency without a statistical significal between Tile C and costal fractures. 61.9% (n = 26) needed blood transfusion; 9.5% (n = 4) presented hypovolemic shock.ConclusionsTile A pelvic fractures were associated with scapular fractures, and Tile B with transforaminal fractures of the sacrum and with visceral injuries (lungs, liver and genitourinary). The small number of Tile C prevent us to confirm an association with any pathology, although they are the ones which presnt more hemodynamically instability and thoracic injuries. 相似文献
3.
《Revista brasileira de otorrinolaringologia (English ed.)》2022,88(4):523-528
IntroductionPapillary thyroid carcinoma is the most frequent endocrine neoplasia and its incidence has tripled over the past 35 years. Although papillary thyroid carcinoma carries a good prognosis, 10%?30% of patients still develop recurrence and metastasis. Some clinical and genetic features are associated with worse prognosis. The most frequent mutation is the BRAF p.V600E, which has been associated with many clinical features of poor prognosis. However, many studies have produced controversial results without any association between BRAF mutation and clinicopathological features of poor prognosis.ObjectiveSince the prognostic value of BRAF mutations remains controversial, this study aims to investigate the importance of this mutation in therapeutic decisions for papillary thyroid carcinoma.MethodsTherefore, we evaluated whether the presence of BRAF mutation is associated with features of poor prognosis in 85 patients with papillary thyroid carcinoma older than 45 years treated at A.C. Camargo Cancer Center, from 1980 to 2007. BRAF mutation was evaluated by pyrosequencing. Statistical analysis was performed using SPSS.ResultsThe mean age of patients was 54 years (range: 45 ? 77 years), 73 were women (85.8%) and 12 were men (14.2%). Among them, 39 cases (45.9%) presented extrathyroidal extension and 11 cases had recurrent disease. BRAF mutation was detected in 57 (67%) patients. No significant association was observed between BRAF mutation and gender (p = 0.743), age (p = 0.236), N-stage (p = 0.423), vascular and perineural infiltration (p = 0.085 or multifocality (p = 1.0). Although not statistically significant, the majority of patients with recurrent disease were BRAF positive (9 out of 11) (p = 0.325). Patients affected by BRAF mutation are associated with tumors larger than 1 cm (p = 0.034) and with extrathyroidal extension (p = 0.033).ConclusionAlthough BRAF testing is widely available, there are no consistent data to support improvement in outcomes from incorporating it into therapeutic decision for thyroid cancer. 相似文献
4.
《Dental materials》2022,38(11):1789-1800
ObjectivesDentin microstructure undergoes changes with age and its materials properties degrade over time. In the present study, we investigate the coupled influence of increased filled tubules and decreased materials properties on the fracture behavior of human dentin.MethodsWe assume degraded materials properties are linked with increased advanced glycation end-products (AGEs) crosslinks in dentin tissue. We use morphological data of human molars to create 2D and 3D models of dentin microstructure, and utilize a phase field fracture framework to study crack growth trajectories. We construct aged dentin samples (i.e., filled tubules and degraded properties) and compare the fracture results with the samples without age-related changes.ResultsThe simulations show an increase in the number of filled tubules can deactivate the toughening mechanisms such as crack deflection and microcracking. In addition, filled tubules have adverse impacts on the ability of peritubular dentin to shield microcracking. We further show how the dentinal tubules’ orientations affect the crack surface growth. We also investigate that an increase in the AGEs level can result in increased brittleness.SignificanceThe developed model and findings of the present study provide region-dependent information on crack growth trajectories as well as more understanding of crack surface growth at the presence of filled tubules. 相似文献
5.
6.
7.
8.
Prithvi Mohandas Rajsirish Bellal Sridharan Senthilvelan Rajagopalan 《Seminars in Arthroplasty》2022,32(2):389-397
BackgroundThe treatment of complex 3- and 4-part proximal humerus fractures (PHFs) in the elderly poses significant challenges because of osteoporosis and fracture comminution. The wide range of surgical options available is evidence of the complex nature of the injury. At present, reverse shoulder replacement is gaining popularity among shoulder surgeons for treating these difficult fractures, and the literature has shown equivalent or superior outcomes with reverse shoulder arthroplasty (RSA). We aimed to analyze the long-term results of these complex PHF treated with reverse shoulder replacement.MethodsFor this study, fractures from 39 patients with a mean age of 63.18 years who were treated with RSA for acute complex fractures of the proximal humerus in our institution between 2013 and 2019 were analyzed (n = 31, acute 4-part fractures; n = 4, acute fracture–dislocation; n = 3, fracture with irreparable cuff tear; n = 1, osteoporotic 2-part fracture). All patients had a standard reverse shoulder replacement (cemented humeral stem n = 37 and uncemented stem n = 2) surgery in a level 1 trauma center. The mean follow-up duration was 60 months (24-111 months). The clinical outcomes (Oxford Shoulder Score and Constant Shoulder Score) and the complications at 6 months, 12 months, and 24 months were analyzed.ResultsOur study found a relatively younger population, with 21 patients (53.84%) aged <66 years. Spearman's correlation showed that younger patients had better signs of improvement in Oxford Shoulder Scores at 2 years (P = .008). The average Oxford Shoulder Score was 39.12 ± 4.327, and the average Constant Shoulder Score was 67.67 on the operated side. The mean active forward elevation was 142.56 ± 22.29º, abduction was 136.538 ± 24.31º, external rotation was 27 ± 9.011º, and internal rotation was 33 ± 20.41º. The overall complication rate of 17.94% (periprosthetic infection n = 2, periprosthetic humerus fracture n = 1, and hematoma evacuation n = 4) in our study was similar to those of recent studies in the literature.ConclusionRSA provides a reliable option for PHFs and offers good results in the form of pain relief and good functional outcomes at 2 years even in a younger age group. Thus, it is fast becoming an important option in treating complex PHF, but we must be wary of the steep learning curve and the complications pertinent to this procedure. 相似文献
9.
对于结直肠癌患者,术后复发转移是导致其死亡的主要原因。大量研究显示中医药在结直肠癌复发转移的预防方面有着良好疗效。本文从临床研究入手,针对疾病不同分期,从结直肠癌术后辨证分型的临床研究及中医药预防结直肠癌复发转移的临床试验研究两方面展开论述,发现问题并给出未来临床研究方向的建议。本文旨在为结直肠癌术后复发转移中医药预防的临床研究提供思路和方法,把控好中医药在结直肠癌全过程防治中关键环节,更好地继承发扬中医药在“治未病”中的独特优势。 相似文献
10.