全文获取类型
收费全文 | 9833篇 |
免费 | 559篇 |
国内免费 | 87篇 |
专业分类
耳鼻咽喉 | 163篇 |
儿科学 | 107篇 |
妇产科学 | 116篇 |
基础医学 | 1554篇 |
口腔科学 | 220篇 |
临床医学 | 700篇 |
内科学 | 1951篇 |
皮肤病学 | 361篇 |
神经病学 | 619篇 |
特种医学 | 515篇 |
外科学 | 1480篇 |
综合类 | 36篇 |
一般理论 | 3篇 |
预防医学 | 385篇 |
眼科学 | 207篇 |
药学 | 852篇 |
中国医学 | 143篇 |
肿瘤学 | 1067篇 |
出版年
2024年 | 10篇 |
2023年 | 81篇 |
2022年 | 235篇 |
2021年 | 415篇 |
2020年 | 149篇 |
2019年 | 265篇 |
2018年 | 301篇 |
2017年 | 233篇 |
2016年 | 378篇 |
2015年 | 462篇 |
2014年 | 541篇 |
2013年 | 557篇 |
2012年 | 891篇 |
2011年 | 796篇 |
2010年 | 478篇 |
2009年 | 388篇 |
2008年 | 575篇 |
2007年 | 521篇 |
2006年 | 473篇 |
2005年 | 462篇 |
2004年 | 379篇 |
2003年 | 322篇 |
2002年 | 249篇 |
2001年 | 258篇 |
2000年 | 218篇 |
1999年 | 154篇 |
1998年 | 71篇 |
1997年 | 54篇 |
1996年 | 41篇 |
1995年 | 50篇 |
1994年 | 37篇 |
1993年 | 31篇 |
1992年 | 72篇 |
1991年 | 52篇 |
1990年 | 40篇 |
1989年 | 36篇 |
1988年 | 37篇 |
1987年 | 31篇 |
1986年 | 25篇 |
1985年 | 23篇 |
1984年 | 9篇 |
1983年 | 9篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 8篇 |
1978年 | 5篇 |
1976年 | 7篇 |
1974年 | 4篇 |
1973年 | 6篇 |
1968年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Proshad N. Efune Matthew J. Hoyt Rita Saynhalath Chul Ahn Matthew F. Pearsall Umar H. Khan Thomas Feehan Dev M. Desai Peter Szmuk 《Paediatric anaesthesia》2023,33(9):754-764
Introduction
Fluid administration is an important aspect of the management of children undergoing liver transplantation and may impact postoperative outcomes. Our aim was to evaluate the association between volume of intraoperative fluid administration and our primary outcome, the duration of postoperative mechanical ventilation following pediatric liver transplantation. Secondary outcomes included intensive care unit length of stay and hospital length of stay.Methods
We conducted a multicenter, retrospective cohort study using electronic data from three major pediatric liver transplant centers. Intraoperative fluid administration was indexed to weight and duration of anesthesia. Univariate and stepwise linear regression analyses were conducted.Results
Among 286 successful pediatric liver transplants, the median duration of postoperative mechanical ventilation was 10.8 h (IQR 0.0, 35.4), the median intensive care unit length of stay was 4.3 days (IQR 2.7, 6.8), and the median hospital length of stay was 13.6 days (9.8, 21.1). Univariate linear regression showed a weak correlation between intraoperative fluids and duration of ventilation (r2 = .037, p = .001). Following stepwise linear regression, intraoperative fluid administration remained weakly correlated (r2 = .161, p = .04) with duration of postoperative ventilation. The following variables were also independently correlated with duration of ventilation: center (Riley Children's Health versus Children's Health Dallas, p = .001), and open abdominal incision after transplant (p = .001).Discussion
The amount of intraoperative fluid administration is correlated with duration of postoperative mechanical ventilation in children undergoing liver transplantation, however, it does not seem to be a strong factor.Conclusions
Other modifiable factors should be sought which may lead to improved postoperative outcomes in this highly vulnerable patient population. 相似文献72.
Jihyun Kim Junshik Hong Seog Gyun Kim Kyung Hoon Hwang Minsu Kim Hee Kyung Ahn Sun Jin Sym Jinny Park Eun Kyung Cho Dong Bok Shin Jae Hoon Lee 《Nuclear Medicine and Molecular Imaging》2014,48(3):187-195
Purpose
The purpose of this study was to evaluate the prognostic value of metabolic tumor volume (MTV) measured by 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT) in patients with diffuse large B-cell lymphoma (DLBCL) treated with rituximab-containing immunochemotherapy.Methods
Patients with newly diagnosed DLBCL who underwent pre-treatment torso FDG-PET/CT scan taken within 10 days before treatment were included. MTV was defined as the volume of hypermetabolic tissue with a standardized uptake value (SUV) greater than a threshold value of 2.5 and calculated using volume viewer software. Association of MTV with patient characteristics and survival were compared.Results
A total of 96 patients were evaluated. During a median follow-up period of 27.8 months, 3-year event-free survival (EFS) and overall survival was 69.5 % and 72.9 %, respectively. The Ann Arbor staging showed a limitation of prognosis because there was no difference of EFS between patients with Ann Arbor stage II and those with stage III. On the contrary, among patients with Ann Arbor stage II or III disease (n?=?53), the higher MTV group showed significantly inferior EFS compared with the lower MTV group.Conclusions
In the current study, we identified the pre-treatment MTV measured by FDG-PET/CT as a potential predictor of survival in patients with DLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP), at least in Ann Arbor stage II and III disease. 相似文献73.
PCGEM1 stimulates proliferation of osteoarthritic synoviocytes by acting as a sponge for miR‐770 下载免费PDF全文
Yeonho Kang Jinsoo Song Dongkyun Kim Chiyeon Ahn Sujung Park Churl‐Hong Chun Eun‐Jung Jin 《Journal of orthopaedic research》2016,34(3):412-418
Long non‐coding RNAs (lncRNAs) have been reported to play important roles in cellular metabolism and development. Various diseases have been associated with aberrant expression of lncRNAs and the related dysregulation of mRNAs. An lncRNA profiling assay was carried out to identify the key lncRNA in osteoarthritic human synoviocytes; the results revealed that prostate cancer gene expression marker 1 (PCGEM1) was significantly overexpressed in osteoarthritic synoviocytes. Exogenous overexpression of PCGEM1 inhibited apoptosis, induced autophagy, and stimulated the proliferation of human synoviocytes. The increased expression of PCGEM1 in human synoviocytes also suppressed the expression of miR‐770. Transfection of the miR‐770 precursor resulted in reduced proliferation, and induced apoptosis of human synoviocytes. This effect of miR‐770 expression was reversed by co‐introduction of PCGEM1. Target validation showed a direct binding between PCGEM1 and miR‐770. We demonstrate that PCGEM1 act as sponge lncRNA for miR‐770 that regulates proliferation/apoptosis and autophagy, and suggest PCGEM1 as possible target for OA therapy. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:412–418, 2016. 相似文献
74.
Cubilin (cubn) is a receptor for vitamins and various protein ligands. Cubn lacks a transmembrane domain but anchors to apical membranes by forming complexes with Amnionless or Megalin. In an effort to better understand the uptake of nutrients in testis, we analysed cubn expression in the developing mice testes. In testes, cubn mRNA increased from birth to adulthood. In the inter‐stitium and isolated seminiferous tubules, neonatal increase in cubn mRNA until 14 days post‐partum (pp) was followed by a marked increase at puberty (28 days pp). Cubn was found in the gonocytes, spermatogonia, spermatocytes and spermatids in the developing testes. In adult testes, strong Cubn immunoreactivity was found in the elongating spermatids, suggesting the role of Cubn in endocytosis during early spermiogenesis. In Sertoli cells and peritubular cells, Cubn immunoreactivity was weak throughout the testis development. In the inter‐stitium, Cubn immunoreactivity was found in foetal Leydig cells, was weak to negligible in the stem cells and progenitor Leydig cells and was strong in immature and adult Leydig cells, demonstrating a positive association between Cubn and steroidogenic activity of Leydig cells. Collectively, these results suggest that Cubn may participate in the endocytotic uptake of nutrients in germ cells and somatic cells, supporting the spermatogenesis and steroidogenesis in mouse testes. 相似文献
75.
Comparing MR imaging and CT in the staging of gastric carcinoma 总被引:49,自引:0,他引:49
Sohn KM Lee JM Lee SY Ahn BY Park SM Kim KM 《AJR. American journal of roentgenology》2000,174(6):1551-1557
OBJECTIVE: The purpose of this study was to assess the usefulness of breath-hold two-dimensional (2D) fast low-angle shot (FLASH) and T2-weighted turbo spin-echo fast MR imaging compared with helical CT in the staging of gastric carcinoma. SUBJECTS AND METHODS: Thirty patients with gastric carcinoma underwent preoperative MR imaging and helical CT. MR imaging at 1.5 T was performed immediately after the intramuscular injection of scopolamine and the oral administration of water or effervescent granules. Breath-hold 2D FLASH T1-weighted images in all three planes, turbo spin-echo T2-weighted axial images, and gadolinium-enhanced fat-suppressed 2D FLASH axial images were included. Helical CT was performed 60 sec after initiation of i.v. contrast medium injection (2.5-3 ml/sec). Two groups of two radiologists each independently analyzed the MR and helical CT findings, and these results were compared with the pathologic findings. RESULTS: For T staging, MR imaging accuracy was higher than that of helical CT (73.3% and 66.7%, respectively); however, the accuracies of the two methods were not significantly different from each other (McNemar test, p > 0.05). Overstaging was noted in 6.7% of cases with MR imaging and 10% with helical CT. Understaging was noted in 20% of cases with MR imaging and 23.3% with helical CT. For N staging, the accuracies of MR imaging and helical CT were 55% and 58.6%, respectively, with no statistical significance (overstaging, 10% and 6.9%; understaging, 34.5% and 34.5%, respectively). CONCLUSION: MR imaging was comparable to helical CT in the T and N staging of gastric cancer. 相似文献
76.
Primary tumors and mediastinal lymph nodes after neoadjuvant concurrent chemoradiotherapy of lung cancer: serial CT findings with pathologic correlation 总被引:10,自引:0,他引:10
Lee KS Shim YM Han J Kim J Ahn YC Park K Jung KJ 《Journal of computer assisted tomography》2000,24(1):35-40
PURPOSE: The purpose of this work was to describe the changes of primary tumor and mediastinal lymph nodes on CT after neoadjuvant concurrent chemoradiotherapy and to correlate the CT findings with pathology. METHOD: Twenty-one consecutive patients [N2 disease (n = 19) or resectable T4 and N2 disease (n = 2)] with non-small cell lung cancer underwent neoadjuvant concurrent chemoradiotherapy. Changes of primary tumor and mediastinal nodes before and after the therapy were assessed using CT. The CT findings were correlated with pathologic findings. RESULTS: With neoadjuvant therapy, decrease in T stage was achieved in 9 of 21 (43%) patients on CT. On pathology, the remaining tumor consisted mostly of fibrosis and necrosis with little proportion of viable tumor cells (mean volume 17%, range 0-55%). Decrease in nodal stage was achieved in 14 of 21 (67%) patients on pathologic examination. Seven patients had cancer cells in mediastinal lymph nodes: in 6 of 9 (67%) patients with adenocarcinoma and 1 of 12 (8%) patients with squamous cell carcinoma (p = 0.016). CONCLUSION: With neoadjuvant concurrent chemoradiotherapy, the remaining tumor consists mostly of fibrosis or necrosis. Decreased nodal stage on pathology is achieved especially in patients with N2 disease of squamous cell carcinoma. The CT findings of the tumor and mediastinal nodes are not helpful in predicting the pathology after the therapy. 相似文献
77.
Canadian Journal of Anesthesia/Journal canadien d'anesthésie - 相似文献
78.
79.
Sirolimus inhibits platelet-derived growth factor-induced collagen synthesis in rat vascular smooth muscle cells 总被引:2,自引:0,他引:2
Vascular smooth muscle cell (VSMC) proliferation and extracellular matrix (ECM) accumulation play key roles in the development and the progression of vascular remodeling such as transplant arteriosclerosis and restenosis. The present study examined the effects of sirolimus (SRL) on platelet-derived growth factor (PDGF)-induced fibronectin secretion, collagen synthesis, and the related signaling pathways including reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPK) in rat VSMCs. Primary rat VSMCs were isolated from male Sprague-Dawley rats. Growth arrested, synchronized cells were treated with various concentrations of SRL before the addition of PDGF at 10 ng/mL. Proliferating cell nuclear antigen expression, fibronectin secretion, and the activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK were assessed by Western blot analysis, collagen synthesis by [(3)H]-proline incorporation, and cellular ROS by flow cytometry. PDGF (10 ng/mL) increased VSMC proliferation by 1.7-fold, fibronectin secretion by 1.5-fold, collagen synthesis by 2.1-fold, cellular ROS by 1.6-fold, and activation of ERK and p38 MAPK by 3.3- and 3.9-fold compared to controls. SRL above 1 nmol/L inhibited PDGF-induced VSMC proliferation and collagen synthesis but not PDGF-induced fibronectin secretion, cellular ROS, and activation of ERK and p38 MAPK. These data demonstrated that PDGF increased ECM synthesis as well as proliferation through cellular ROS and subsequent MAPK activation and that SRL inhibited PDGF-induced VSMC proliferation and collagen synthesis in a cellular ROS- and MAPK activation-independent way. 相似文献
80.
Anterior translocation of the pulmonary root was used as a new approach to the staged repair of Taussig-Bing anomaly with an interrupted aortic arch. It was performed to construct the right ventricle outflow tract with intraventricular baffling of the left ventricle to the aorta as the second stage operation after repair of the interrupted arch and pulmonary artery banding. This technique allows minimization of pulmonary regurgitation and has the major theoretical advantage for growth potential, which could diminish the need for reoperation. 相似文献