全文获取类型
收费全文 | 14912篇 |
免费 | 1024篇 |
国内免费 | 152篇 |
专业分类
耳鼻咽喉 | 200篇 |
儿科学 | 340篇 |
妇产科学 | 164篇 |
基础医学 | 1839篇 |
口腔科学 | 230篇 |
临床医学 | 1189篇 |
内科学 | 3902篇 |
皮肤病学 | 331篇 |
神经病学 | 1031篇 |
特种医学 | 613篇 |
外科学 | 2106篇 |
综合类 | 201篇 |
一般理论 | 21篇 |
预防医学 | 1075篇 |
眼科学 | 350篇 |
药学 | 906篇 |
中国医学 | 60篇 |
肿瘤学 | 1530篇 |
出版年
2024年 | 14篇 |
2023年 | 96篇 |
2022年 | 198篇 |
2021年 | 341篇 |
2020年 | 236篇 |
2019年 | 330篇 |
2018年 | 375篇 |
2017年 | 354篇 |
2016年 | 401篇 |
2015年 | 438篇 |
2014年 | 552篇 |
2013年 | 683篇 |
2012年 | 1117篇 |
2011年 | 1071篇 |
2010年 | 666篇 |
2009年 | 528篇 |
2008年 | 1002篇 |
2007年 | 1103篇 |
2006年 | 977篇 |
2005年 | 1030篇 |
2004年 | 885篇 |
2003年 | 957篇 |
2002年 | 899篇 |
2001年 | 135篇 |
2000年 | 114篇 |
1999年 | 134篇 |
1998年 | 167篇 |
1997年 | 178篇 |
1996年 | 139篇 |
1995年 | 131篇 |
1994年 | 89篇 |
1993年 | 77篇 |
1992年 | 63篇 |
1991年 | 51篇 |
1990年 | 46篇 |
1989年 | 38篇 |
1988年 | 34篇 |
1987年 | 29篇 |
1986年 | 22篇 |
1985年 | 24篇 |
1984年 | 27篇 |
1983年 | 31篇 |
1982年 | 28篇 |
1981年 | 24篇 |
1980年 | 29篇 |
1978年 | 23篇 |
1977年 | 28篇 |
1976年 | 17篇 |
1973年 | 15篇 |
1966年 | 13篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Peter Reimer Sanjay Saini Ken K. Kwong Mark S. Cohen Ralph Weissleder Thomas J. Brady 《Journal of magnetic resonance imaging : JMRI》1994,4(3):331-335
To develop guidelines for clinical magnetic resonance imaging of the liver, the authors undertook an animal study to investigate the effect of dose and pulse sequence on liver signal intensity in gadopentetate dimeglumine—enhanced echo-planar imaging. Serial imaging of the liver was performed in anesthetized rats after intravenous administration of five different doses (0.01, 0.05, 0.1, 0.2, and 0.5 mmol/kg) of contrast agent, with six different pulse sequences. The results show that gadopentetate dimeglumine—enhanced echo-planar images obtained during the perfusion phase can yield either positive (due to increased T1 relaxation rates) or negative (due to susceptibility-induced increased T2 relaxation rates) liver enhancement depending on choice of pulse sequence and dose. At the current clinically recommended dose of 0.1 mmol/kg, maximal liver signal enhancement was seen with a T1-weighted inversion-recovery sequence, while maximal liver signal diminution was seen with a T2*-weighted gradient-echo sequence. The authors conclude that gadopentetate dimeglumine—enhanced echo-planar imaging can provide T1, T2, and T2* contrast that may be exploited for both lesion detection and lesion characterization. 相似文献
42.
43.
Masayuki Imamura Yutaka Shimada Yuhji Kanda Manabu Fukumoto Ken Yanagibashi Tokiharu Miyahara Takayoshi Tobe 《Surgery today》1992,22(5):409-415
In order to decrease the perioperative complications by preoperative cisplatin chemotherapy, the preoperative single administration of cisplatin (30 mg/m2) was performed weekly from one to six times in 36 consecutive patients with esophageal cancer classified as higher than Stage II. The survival curve of 17 patients in Stage III was significantly better (P<0.05) than that of patients who had been treated without preoperative cisplatin treatment. In 3 of the 12 patients who had locally invasive cancer, either the main tumors or the metastatic lymph nodes, which had invaded the trachea or the left main bronchus, sufficiently receded, so that a curative esophagectomy became possible; 2 of them have survived over 33 months while 1 died of pneumonia 33 months after surgery. The number of perioperative complications was minimal, and thus, we consider that the postoperative use of cisplatin and fluorouracil is indicated in patients in whom a histological response is noted in the resected specimens.This work was partially supported by Grant No. 02454315 from the Japanese Ministry of Education 相似文献
44.
消化道恶性肿瘤确诊初期患者社会支持与生命质量的调查 总被引:6,自引:1,他引:5
目的 调查消化道恶性肿瘤确诊初期的患者半年中的社会支持和生命质量变化。方法 采用社会支持评定量表和CARES-SF对146名患者的社会支持和生命质量进行为期半年的追踪调查。结果 消化道恶性肿瘤确诊初期患者的生命质量为中等,其中婚姻关系维度、性关系维度得分半年后下降。患者所获得的社会支持最多的是情感支持,其次是实际支持,信息支持为第三位。情感支持大多来源于家庭成员,信息支持大多来源于医务人员。患者大多很少参与社交活动。在半年中情感支持、实际支持、信息支持的变化模式不一。诊断初期的患者不能有效地利用社会支持。结论 应对确诊初期患者加强咨询,以充分识别和利用社会资源。应持续评估患者的生命质量和社会支持,并制订干预方案,提高消化道恶性肿瘤确诊初期患者的社会支持程度,最终提高其生命质量。 相似文献
45.
46.
47.
48.
We describe a case of elastosis perforans serpiginosa with additional findings of degenerative skin changes. A 20-year-old man with hepatolenticular degeneration, under prolonged treatment with D-penicillamine, presented with a circular or serpiginous arrangement of nuchal papules. Histopathologically, transepidermal channels were accompanied by granulomatous reactions, with several giant cells engulfing elastic fibers. In addition to these findings of a typical elastosis perforans serpiginosa, we observed scar-like skin changes inside the circular arrangement of the papules. At the scar-like tissue, we found electron-microscopical evidence of randomly aggregated thin collagen fibers with no tendency toward systemic combined bundle formation, which is a characteristic feature of normal collagen fiber formation. Pseudoxanthoma-elasticum-like changes were observed on his neck. On his axillae and groin, slight skin thickening and wrinkling were detected. The diagnosis of elastosis perforans serpiginosa does not represent all of the manifestations or the pathological background described above. The skin manifestations described here represent not only an elastosis but also a total degenerative dermatosis with over-healed collagenosis. Thus, those dermatoses should be summarized as one entity, penicillamine-induced degenerative dermatosis. After considering the pathogenic background and clinical similarities, we further propose to simplify the penicillamine-induced skin manifestations to three categories: acute sensitivity reactions, bullous dermatoses, and degenerative dermatoses. 相似文献
49.
Expression of cell-matrix molecules and integrin receptors in human liver grafts during chronic rejection 总被引:1,自引:0,他引:1
Ken Hoshino Bjorn Nashan Gustav Steinhoff Rudolf Pichlmayr K. Hoshino 《Transplant international》1994,7(S1):637-640
Abstract The inflammatory response of immune cells to target cells and cell-matrix molecules is regulated by several receptor-ligand molecules. As fibrosis develops in ongoing chronic rejection after liver transplantation, it is of interest to analyze patterns of integrin receptors and cell-matrix molecules in order to study the relation between immune cells and the stromal and parenchymal cells. In the present study, we demonstrated the expression of these molecules in chronic rejected human liver grafts using immunohistochemical techniques. The results showed a differential expression and induction of integrin receptors and cell-matrix molecules on resident liver cells, especially on sinusoids, reflecting a state of chronic inflammation and a specific interaction between integrin receptors and cell-matrix molecules. The patterns of induced integrin receptors on graft-infiltrating cells was closely related to the local production of cell-matrix molecules and reflected the final sequence of a stepwise progress of the inflammatory reaction. 相似文献
50.
Katsushige Tada Ken Nagao Katsuhisa Tanjoh Nariyuki Hayashi 《Circulation journal》2006,70(8):1064-1069
BACKGROUND: Although an elevated blood glucose has prognostic value in cardiovascular disease, few data are available regarding its prognostic value for patients across the spectrum of cardiogenic shock. METHOD AND RESULTS: A total of 81 patients with cardiogenic shock whose blood glucose and adrenaline were measured on arrival at the emergency room (ER) were enrolled in this prospective study. The primary endpoint was death from any cause in hospital. The rate of death was 12.3% (10/81), and the glucose level was lower among patients who were discharged alive than among those who died (8.7+/-3.7 mmol/L vs 13.8+/-6.7 mmol/L, p<0.001). The unadjusted rate of death increased in a stepwise fashion among patients in increasing quartiles of glucose level (p<0.05). The blood glucose level of 9.2 mmol/L had the highest combined sensitivity and specificity for the identification of death. In the multiple logistic-regression analysis for the primary outcome, the adjusted odd ratio for a glucose level of 9.2 mmol/L or more was 5.8 (95% confidence interval, 1.0-32.8, p=0.047). There was a significant positive correlation between the glucose and adrenaline levels (R=0.726, p<0.0001). CONCLUSION: The measurement of blood glucose level on ER arrival provides predictive information for use in risk stratification across the spectrum of cardiac emergencies complicated by cardiogenic shock. 相似文献