全文获取类型
收费全文 | 1149篇 |
免费 | 90篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 87篇 |
妇产科学 | 65篇 |
基础医学 | 120篇 |
口腔科学 | 28篇 |
临床医学 | 104篇 |
内科学 | 210篇 |
皮肤病学 | 54篇 |
神经病学 | 95篇 |
特种医学 | 31篇 |
外科学 | 96篇 |
综合类 | 8篇 |
一般理论 | 1篇 |
预防医学 | 63篇 |
眼科学 | 73篇 |
药学 | 111篇 |
中国医学 | 5篇 |
肿瘤学 | 84篇 |
出版年
2024年 | 1篇 |
2023年 | 23篇 |
2022年 | 58篇 |
2021年 | 70篇 |
2020年 | 62篇 |
2019年 | 75篇 |
2018年 | 82篇 |
2017年 | 58篇 |
2016年 | 83篇 |
2015年 | 53篇 |
2014年 | 88篇 |
2013年 | 88篇 |
2012年 | 98篇 |
2011年 | 98篇 |
2010年 | 46篇 |
2009年 | 43篇 |
2008年 | 62篇 |
2007年 | 60篇 |
2006年 | 43篇 |
2005年 | 27篇 |
2004年 | 14篇 |
2003年 | 5篇 |
2002年 | 3篇 |
1994年 | 1篇 |
排序方式: 共有1241条查询结果,搜索用时 15 毫秒
31.
32.
33.
Gunjan Arora Manavi Yadav Rashmi Gaur Radhika Gupta Pooja Rana Priya Yadav Rakesh Kumar Sharma 《RSC advances》2020,10(33):19390
In the present report, an environmentally benign magnetically recoverable nickel(ii)-based nanoreactor as a heterogeneous catalyst has been developed via a template free approach. The catalytic performance of the synthesized catalyst is assessed in the confined oxidative coupling of arenethiols with arylhydrazines to form unsymmetrical diaryl sulfides under aerobic conditions. The salient features of our protocol include oxidant- and ligand-free conditions, use of water as a green solvent, room temperature and formation of nitrogen and water as the only by-products. Moreover, a broad range of functional groups are tolerated well and provide the corresponding diaryl sulfides in moderate to good yields. Moreover, the heterogeneous nature of the catalyst permits facile magnetic recovery and reusability for up to seven runs, making the present protocol highly desirable from industrial and environmental standpoints.An environmentally benign nickel(ii)-based magnetic nanoreactor has been developed for oxidative coupling of arenethiols with arylhydrazines to form unsymmetrical diaryl sulfides in water at room temperature. 相似文献
34.
Anne Tsampalieros Pooja Gupta Michelle R Denburg Justine Shults Babette S Zemel Sogol Mostoufi‐Moab Rachel J Wetzsteon Rita M Herskovitz Krista M Whitehead Mary B Leonard 《Journal of bone and mineral research》2013,28(3):480-488
The impact of glucocorticoids (GC) on skeletal development has not been established. The objective of this study was to examine changes in volumetric bone mineral density (vBMD) and cortical structure over 1 year in childhood nephrotic syndrome (NS) and to identify associations with concurrent GC exposure and growth. Fifty‐six NS participants, aged 5 to 21 years, were enrolled a median of 4.3 (0.5 to 8.1) years after diagnosis. Tibia peripheral quantitative computed tomography (pQCT) scans were obtained at enrollment and 6 and 12 months later. Sex, race, and age‐specific Z‐scores were generated for trabecular vBMD (TrabBMD‐Z), cortical vBMD (CortBMD‐Z), and cortical area (CortArea‐Z) based on >650 reference participants. CortArea‐Z was further adjusted for tibia length‐for‐age Z‐score. Quasi‐least squares regression was used to identify determinants of changes in pQCT Z‐scores. At enrollment, mean TrabBMD‐Z (?0.54 ± 1.32) was significantly lower (p = 0.0001) and CortBMD‐Z (0.73 ± 1.16, p < 0.0001) and CortArea‐Z (0.27 ± 0.91, p = 0.03) significantly greater in NS versus reference participants, as previously described. Forty‐eight (86%) participants were treated with GC over the study interval (median dose 0.29 mg/kg/day). On average, TrabBMD‐Z and CortBMD‐Z did not change significantly over the study interval; however, CortArea‐Z decreased (p = 0.003). Greater GC dose (p < 0.001), lesser increases in tibia length (p < 0.001), and lesser increases in CortArea‐Z (p = 0.003) were independently associated with greater increases in CortBMD‐Z. Greater increases in tibia length were associated with greater declines in CortArea‐Z (p < 0.01); this association was absent in reference participants (interaction p < 0.02). In conclusion, GC therapy was associated with increases in CortBMD‐Z, potentially related to suppressed bone formation and greater secondary mineralization. Conversely, greater growth and expansion of CortArea‐Z (ie, new bone formation) were associated with declines in CortBMD‐Z. Greater linear growth was associated with impaired expansion of cortical area in NS. Studies are needed to determine the fracture implications of these findings. © 2013 American Society for Bone and Mineral Research. 相似文献
35.
36.
37.
38.
Marshall C. Strother Alexander Kutikov Matthew Epstein Emily Bochner Mengying Deng Elizabeth Handorf Bianca Lewis Pooja Ghatalia Richard E. Greenberg David Chen Rosalia Viterbo Fern Anari Marc C. Smaldone Matthew R. Zibelman Robert G. Uzzo Elizabeth R. Plimack Daniel M. Geynisman 《BJU international》2022,129(3):364-372
39.
Anish Jacob Cherian Mahasampath Gowri Pooja Ramakant Thomas V. Paul Deepak Thomas Abraham Mazhuvanchary Jacob Paul 《World journal of surgery》2016,40(4):881-888
Background
The purpose of this study was to determine the prevalence of hypomagnesemia in patients undergoing thyroidectomy and evaluate the relationship of hypomagnesemia with transient and severe hypocalcemia.Materials and methods
This was a prospective observational study of 50 patients undergoing thyroidectomy. Blood samples were collected pre- and postoperatively for calcium, albumin, magnesium, phosphorous and parathormone (PTH). Signs, symptoms of hypocalcemia and volume of intravenous fluids used perioperatively were documented. The statistical analysis was performed using STATA I/C 10.1.Results
Preoperatively, twelve patients (24 %) had hypomagnesemia and one (2 %) hypocalcemia. On the first postoperative day, hypomagnesemia was seen in 70 % and hypocalcemia in 30 %. A similar trend was observed in the fall and rise of postoperative calcium and magnesium values (p = 0.41). Severe hypocalcemia was present in three patients (6 %). All three patients had a very low postoperative PTH (<2 pg/ml). Among them, two patients (66 %) had hypomagnesemia and their hypocalcemia responded to intravenous magnesium correction. Significant risk factors for postoperative hypocalcemia include a higher volume of fluid used perioperatively and low postoperative PTH (<8 pg/ml) (p = 0.01 and 0.03, respectively).Conclusion
Preoperative hypomagnesemia (24 %) was prevalent in this cohort of patients. Postoperative hypomagnesemia is a common event (70 %) following total thyroidectomy, and magnesium levels tend to mimic the calcium levels postoperatively. The cause of hypocalcemia post-thyroidectomy in this study is mainly a factor of parathyroid function and fluid status. Severe hypocalcemia is a rare event, and hypomagnesemia is associated in the majority of these patients. The role of magnesium correction to alleviate severe hypocalcemia needs to be further studied.40.