全文获取类型
收费全文 | 10485篇 |
免费 | 525篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 107篇 |
儿科学 | 204篇 |
妇产科学 | 185篇 |
基础医学 | 1431篇 |
口腔科学 | 332篇 |
临床医学 | 621篇 |
内科学 | 2435篇 |
皮肤病学 | 225篇 |
神经病学 | 734篇 |
特种医学 | 343篇 |
外科学 | 1925篇 |
综合类 | 48篇 |
预防医学 | 367篇 |
眼科学 | 173篇 |
药学 | 724篇 |
中国医学 | 11篇 |
肿瘤学 | 1204篇 |
出版年
2023年 | 55篇 |
2022年 | 86篇 |
2021年 | 184篇 |
2020年 | 92篇 |
2019年 | 136篇 |
2018年 | 188篇 |
2017年 | 136篇 |
2016年 | 168篇 |
2015年 | 212篇 |
2014年 | 211篇 |
2013年 | 341篇 |
2012年 | 523篇 |
2011年 | 528篇 |
2010年 | 319篇 |
2009年 | 262篇 |
2008年 | 554篇 |
2007年 | 550篇 |
2006年 | 597篇 |
2005年 | 605篇 |
2004年 | 585篇 |
2003年 | 518篇 |
2002年 | 602篇 |
2001年 | 332篇 |
2000年 | 301篇 |
1999年 | 309篇 |
1998年 | 186篇 |
1997年 | 144篇 |
1996年 | 147篇 |
1995年 | 106篇 |
1994年 | 98篇 |
1993年 | 85篇 |
1992年 | 182篇 |
1991年 | 178篇 |
1990年 | 198篇 |
1989年 | 169篇 |
1988年 | 130篇 |
1987年 | 109篇 |
1986年 | 118篇 |
1985年 | 100篇 |
1984年 | 85篇 |
1983年 | 81篇 |
1982年 | 43篇 |
1981年 | 36篇 |
1979年 | 71篇 |
1978年 | 41篇 |
1977年 | 34篇 |
1976年 | 30篇 |
1972年 | 29篇 |
1971年 | 32篇 |
1970年 | 32篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
993.
Yoshihiko Shimizu Ling Jin Hiroshi Yamaguchi Utaroh Motosugi Seiya Sannohe Koji Nagata Takaki Sakurai Shinichi Murata Masanori Yasuda Michio Shimizu 《Annals of diagnostic pathology》2009,13(3):168-172
We investigated the presence of lymphatic invasion detected by D2-40 immunostaining compared to conventional hematoxylin-eosin (HE) staining in primary pancreatic cancer. We also compared the alkaline phosphatase-fast red detection method with the 3,3′-diaminobenzidine (DAB) detection method. We reviewed 25 cases of pancreatic cancer with lymph node (LN) metastases and 15 cases without LN metastases and evaluated the detection rate of lymphatic invasion by HE stain slide alone and D2-40 immunostains. Regarding the cases with positive LN metastasis, 4 (16%) of the 25 cases showed lymphatic invasion by HE slide alone, whereas 7 cases (28%) demonstrated positive lymphatic invasion by D2-40 immunostain. On the other hand, even in cases with negative LN metastasis, 3 of the 15 cases revealed lymphatic invasion by D2-40 immunostaining. Lymphatic invasion was easily detected by alkaline phosphatase-fast red technique, especially at the lower magnification. Regarding the location of lymphatic invasion, it was recognized not only at the peripheral portion but also in the central part of the tumors by D2-40 immunostains; this was difficult to identify by HE stain slide alone. Our study indicates that lymphatic invasion may be overlooked when only HE stain slides are used. In addition, the alkaline phosphatase-fast red detection method (vivid red color) is a distinctive advantage compared with the DAB detection method (brown color), especially in detecting lymphatic invasion at the lower magnification. 相似文献
994.
995.
This paper describes a study in which numerical simulations were applied to improve the separation efficiency of a microfluidic-based
sperm sorter. Initially, the motion of 31 sperm were modeled as a sinusoidal wave. The modeled sperm were expected to move
while vibrating in the fluid within the microchannel. In this analysis, the number of sperm extracted at the outlet channel
and the rate of movement of the highly motile sperm were obtained for a wide range of flow velocities within the microchannel.
By varying the channel height, and the width and the position of the sperm-inlet channel, we confirmed that the separation
efficiency was highly dependent on the fluid velocity within the channel. These results will be valuable for improving the
device configuration, and might help to realize further improvements in efficiency in the future. 相似文献
996.
997.
Toshiyuki Komiya Norihiko Goto Asami Takeda Keiji Horike Hiroshi Onoda Kaoru Sakai Ken Kitamura Keiko Yamamoto Tadashi Oikawa Takaharu Nagasaka Takahisa Hiramitsu Syuichi Simabukuro Keisuke Suzuki Tetsuhiko Sato Watarai Yoshihiko Kazuharu Uchida Kunio Morozumi 《Clinical transplantation》2009,23(S20):27-30
Abstract: We report clinical and histopathologic findings of a case of acute rejection with adenovirus infection after kidney transplantation. A 63-yr-old woman with end-stage renal disease caused by lupus nephritis received an ABO-incompatible living kidney transplantation from her husband. On the 7th post-operative day (POD), she had fever, hematuria, and bladder irritation. Although she was treated with an antibiotic, the symptoms were not improved. We diagnosed adenovirus infection as positive with the urine shell vial method and blood PCR analysis. Cyclophosphamide was interrupted and immunoglobulin therapy was performed. However, urine output decreased and serum creatinine levels increased. An episode biopsy was performed on POD 20. We diagnosed acute antibody-mediated rejection. She was treated with plasma exchange for acute rejection and antiviral drug (rivabirin) for active adenovirus infection. However, the renal graft dysfunction was deemed irreversible and the renal graft was removed on POD 34. The graftectomy specimen showed acute rejection and acute tubular necrosis with adenovirus infection. 相似文献
998.
Tomoyuki Nagata md Kazuhiro Ishii md Tatsuhiko Ito md Kimiyoshi Aoki md Yoshito Ehara md Hidehiro Kada md Haruko Furukawa cp Maki Tsumura cp Shunichiro Shinagawa md phd Hiroo Kasahara md phd Kazuhiko Nakayama md phd 《Psychiatry and clinical neurosciences》2009,63(4):449-454
Aims: The purpose of the present study was to investigate the relationship between delusional thoughts (delusional ideation or misidentification) and frontal lobe function using the Japanese version of the Frontal Assessment Battery (FAB) bedside screening neuropsychological test in early stage Alzheimer's disease (AD) patients.
Methods: Forty-eight probable AD patients with Mini-Mental State Examination score ≧18 points and a clinical dementia rating score of either 0.5 or 1.0 were divided into two groups based on data obtained from interviews with their caregivers: a delusional thought group ( n = 19) and a non-delusional thought group ( n = 29). The FAB total and subtest scores were then compared for the two groups.
Results: Significant differences were found between the FAB total ( P < 0.01) and subtest scores (similarities, motor series, conflicting instructions; P < 0.05) for the two groups. Multiple regression analysis showed that delusional thought was significantly associated with the FAB total score.
Conclusions: In addition to episodic memory disorders, a reduction in the FAB score may reflect frontal lobe dysfunctions, including executive function, in patients with AD, leading to delusional ideation. 相似文献
Methods: Forty-eight probable AD patients with Mini-Mental State Examination score ≧18 points and a clinical dementia rating score of either 0.5 or 1.0 were divided into two groups based on data obtained from interviews with their caregivers: a delusional thought group ( n = 19) and a non-delusional thought group ( n = 29). The FAB total and subtest scores were then compared for the two groups.
Results: Significant differences were found between the FAB total ( P < 0.01) and subtest scores (similarities, motor series, conflicting instructions; P < 0.05) for the two groups. Multiple regression analysis showed that delusional thought was significantly associated with the FAB total score.
Conclusions: In addition to episodic memory disorders, a reduction in the FAB score may reflect frontal lobe dysfunctions, including executive function, in patients with AD, leading to delusional ideation. 相似文献
999.
CXCL12 and CCL20 play a significant role in mucosal T-lymphocyte adherence to intestinal microvessels in mice 总被引:1,自引:0,他引:1
Oyama T Miura S Watanabe C Hokari R Fujiyama Y Komoto S Tsuzuki Y Hosoe N Nagata H Hibi T 《Microcirculation (New York, N.Y. : 1994)》2007,14(7):753-766
OBJECTIVE: Although it is known that the chemokines CXCL12 and CCL20 are expressed in the intestine, their contribution to lymphocyte homing has not been investigated in detail. The authors investigated whether the CXCL12-CXCR4 and CCL20-CCR6 systems are involved in T lymphocyte-endothelial interaction in microvessels of the small and large intestines. METHODS: Labeled lamina proprial lymphocytes (LPLs) were administered to mice, and their adhesion to microvessels of normal and TNF-alpha -induced inflamed intestinal mucosa was observed under an intravital microscope. Antibodies against CXCL12, CCL-20, or CCL-25 were administered prior to lymphocyte administration, and in some experiments CXCR4 or CCR6 on LPLs was desensitized with an excess amount of chemokine. RESULTS: LPLs adhered to microvessels of the ileum and colon, and TNF-alpha induced a significant accumulation at both sites. Blocking of the CXCL12-CXCR4 system significantly inhibited the LPL adhesion in the ileum and colon under both normal and TNF-alpha -treated conditions. However, blocking of the CCL20-CCR6 system significantly attenuated LPL adhesion only under a TNF-alpha -treated condition. There was an additive inhibitory effect on LPL adherence by CXCL12 and CCL20 blocking in TNF-alpha -induced inflamed intestines. There was also an additive function of the CCL25-CCR9 system in LPL accumulation in the small intestine. CONCLUSION: Several chemokine systems may play significant roles cooperatively in vivo in LPL adherence to microvessels of intestinal mucosa. 相似文献
1000.
Aoki-Nagase T Nagase T Oh-Hashi Y Kurihara Y Yamaguchi Y Yamamoto H Nagata T Kurihara H Ouchi Y 《Respirology (Carlton, Vic.)》2007,12(6):807-813
BACKGROUND AND OBJECTIVE: Acid-induced lung injury from aspiration is one of the most important causes of ARDS. Calcitonin gene-related peptide (CGRP) is a neuropeptide that has various biological actions. The current study investigated whether CGRP might have pathophysiological roles in acid-induced lung injury. METHODS: The investigations employed CGRP gene-disrupted mice--mutant mice (CGRP(-/-)) and their littermate controls (CGRP(+/+)). Anaesthetized and mechanically ventilated mice received 2 mL/kg HCl (pH = 1.5) intratracheally. Lung wet-to-dry weight ratios were calculated to assess pulmonary oedema, total and differential cell counts of the BALF were determined, and measurements of myeloperoxidase activity were performed. RESULTS: Acid-induced lung injury was characterized by an increase in lung permeability and respiratory failure. Disruption of the CGRP gene significantly attenuated acid-induced injury, oedema and respiratory failure. CONCLUSIONS: This study suggests that CGRP is involved in the pathogenesis of acute lung injury caused by acid aspiration and CGRP mutant mice may provide an appropriate model to study molecular mechanisms in this context. 相似文献