全文获取类型
收费全文 | 8693篇 |
免费 | 366篇 |
国内免费 | 74篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 263篇 |
妇产科学 | 73篇 |
基础医学 | 1304篇 |
口腔科学 | 158篇 |
临床医学 | 513篇 |
内科学 | 2569篇 |
皮肤病学 | 182篇 |
神经病学 | 725篇 |
特种医学 | 232篇 |
外科学 | 1131篇 |
综合类 | 19篇 |
预防医学 | 211篇 |
眼科学 | 99篇 |
药学 | 709篇 |
中国医学 | 43篇 |
肿瘤学 | 825篇 |
出版年
2023年 | 35篇 |
2022年 | 58篇 |
2021年 | 145篇 |
2020年 | 55篇 |
2019年 | 100篇 |
2018年 | 125篇 |
2017年 | 93篇 |
2016年 | 138篇 |
2015年 | 143篇 |
2014年 | 192篇 |
2013年 | 255篇 |
2012年 | 453篇 |
2011年 | 474篇 |
2010年 | 283篇 |
2009年 | 257篇 |
2008年 | 526篇 |
2007年 | 598篇 |
2006年 | 550篇 |
2005年 | 597篇 |
2004年 | 618篇 |
2003年 | 619篇 |
2002年 | 656篇 |
2001年 | 100篇 |
2000年 | 51篇 |
1999年 | 135篇 |
1998年 | 166篇 |
1997年 | 125篇 |
1996年 | 144篇 |
1995年 | 127篇 |
1994年 | 141篇 |
1993年 | 146篇 |
1992年 | 95篇 |
1991年 | 85篇 |
1990年 | 74篇 |
1989年 | 81篇 |
1988年 | 50篇 |
1987年 | 49篇 |
1986年 | 40篇 |
1985年 | 40篇 |
1984年 | 50篇 |
1983年 | 44篇 |
1982年 | 63篇 |
1981年 | 56篇 |
1980年 | 36篇 |
1979年 | 31篇 |
1978年 | 26篇 |
1977年 | 19篇 |
1976年 | 25篇 |
1975年 | 21篇 |
1973年 | 16篇 |
排序方式: 共有9133条查询结果,搜索用时 31 毫秒
991.
Ikomi F Kawai Y Nakayama J Ogiwara N Sasaki K Mizuno R Ohhashi T 《Microcirculation (New York, N.Y. : 1994)》2008,15(7):591-603
Molecular mechanisms of reconnection of collecting lymph vessels were analyzed by using murine popliteal prenodal lymph vessels. At 1 and 2 weeks after being divided by cutting the lymph vessel, lymphatic reconnection was frequently observed accompanied by mesh-like lymphatic channels. Electron microscopic study also showed a monolayer of endothelial cells in the newly developed lymph vessels. Smooth muscle markers were immunofluorescently demonstrated in the wall of the new vessels. At 1 week after the procedure of cutting, augmented expressions of VEGF receptors 1, 2 and 3 were found immunohistochemically at the site of the reconnected lymph vessels. The expression of mRNA for VEGF receptor 3 was enhanced at 5 days and 1 week in small pieces of the tissues containing the reconnected lymph vessels, compared with that in the corresponding tissues obtained with sham operated ones. The administration of VEGF-C at the cutting site of the collecting lymph vessel significantly increased the rate of the reconnected lymph vessels, whereas additional treatment with Flt4/Fc chimera protein significantly reduced the rate of the reconnected ones. These results suggest that activation of VEGF-C-VEGF receptor 3 has critical roles in reconnection of the collecting lymph vessels in adult mice. 相似文献
992.
Laboratory parameters identify familial haemophagocytic lymphohistiocytosis from other forms of paediatric haemophagocytosis 下载免费PDF全文
Takahiro Yasumi Masayuki Hori Eitaro Hiejima Hirofumi Shibata Kazushi Izawa Hirotsugu Oda Kouhei Yoshioka Kenji Nakagawa Tomoki Kawai Ryuta Nishikomori Osamu Ohara Toshio Heike 《British journal of haematology》2015,170(4):532-538
Haemophagocytic lymphohistiocytosis (HLH) is a life‐threatening syndrome of immune dysregulation and is classified as primary or secondary according to the underlying aetiology. The treatment strategies recommended for these two groups differ substantially; however, it is thought to be impossible to predict the underlying causes of HLH using conventional laboratory tests. Recent studies show that serum levels of soluble interleukin‐2 receptor (sIL2R) and ferritin are useful for differentiating some forms of HLH. The present study reports that combinations of common laboratory parameters, such as the percentage of total lymphocytes within the peripheral blood leucocyte population, serum levels of lactate dehydrogenase and the sIL2R/ferritin ratio, are useful for identifying patients with familial haemophagocytic lymphohistiocytosis and for differentiating the underlying aetiology of paediatric HLH during the early course of the disease. These findings suggest that the pathogenesis of HLH differs greatly in terms of innate and adaptive immunity depending on the aetiology and may provide a new approach to unravelling the complex pathophysiology underlying this syndrome. 相似文献
993.
Long-term follow-up of a patient with idiopathic myelofibrosis associated with chromosome 11 and 13 abnormalities 总被引:2,自引:0,他引:2
Toubai T Tanaka J Higa T Ota S Ibata M Shono Y Mashiko S Miura Y Umehara S Kahata K Toyoshima N Morioka M Asaka M Kasai M Imamura M 《American journal of hematology》2005,78(1):67-70
A case of a leukemic transformation following a 27-year history of idiopathic myelofibrosis (IMF) is presented. The patient had two chromosomal abnormalities: a deletion of chromosome 13, del 13(q12q14), and a deletion of chromosome 11, del 11(q14q23). This patient's final diagnosis was acute micromegakaryocytic leukemia, and she died 1 month after leukemic transformation with an additional chromosomal abnormality, trisomy 8. IMF with myeloid metaplasia associated with deletion of the long arms of chromosomes 11 and 13 has not been previously reported. We speculate that the leukemic transformation in this patient was associated with chromosomal abnormalities del 11 and trisomy 8. 相似文献
994.
Nationwide Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation (J-POPS)
Shiro Saito Kazuto Ito Atsunori Yorozu Manabu Aoki Hirofumi Koga Takefumi Satoh Toshio Ohashi Naoyuki Shigematsu Shinichiro Maruo Takashi Kikuchi Shinsuke Kojima Takushi Dokiya Masanori Fukushima Hidetoshi Yamanaka 《International journal of clinical oncology / Japan Society of Clinical Oncology》2015,20(2):375-385
995.
996.
997.
Akihisa Kato Aya Naiki-Ito Takahiro Nakazawa Kazuki Hayashi Itaru Naitoh Katsuyuki Miyabe Shuya Shimizu Hiromu Kondo Yuji Nishi Michihiro Yoshida Shuichiro Umemura Yasuki Hori Toshio Mori Masahiro Tsutsumi Toshiya Kuno Shugo Suzuki Hiroyuki Kato Hirotaka Ohara Takashi Joh Satoru Takahashi 《Oncotarget》2015,6(40):42963-42975
Despite progress in clinical cancer medicine in multiple fields, the prognosis of pancreatic cancer has remained dismal. Recently, chemopreventive strategies using phytochemicals have gained considerable attention as an alternative in the management of cancer. The present study aimed to evaluate the chemopreventive effects of resveratrol (RV) and apocynin (AC) in N-Nitrosobis(2-oxopropyl)amine-induced pancreatic carcinogenesis in hamster. RV- and AC-treated hamsters showed significant reduction in the incidence of pancreatic cancer with a decrease in Ki-67 labeling index in dysplastic lesions. RV and AC suppressed cell proliferation of human and hamster pancreatic cancer cells by inhibiting the G1 phase of the cell cycle with cyclin D1 downregulation and inactivation of AKT-GSK3β and ERK1/2 signaling. Further, decreased levels of GSK3βSer9 and ERK1/2 phosphorylation and cyclin D1 expression in the nuclear fraction were observed in cells treated with RV or AC. Nuclear expression of phosphorylated GSK3βSer9 was also decreased in dysplastic lesions and adenocarcinomas of hamsters treated with RV or AC in vivo. These results suggest that RV and AC reduce phosphorylated GSK3βSer9 and ERK1/2 in the nucleus, resulting in inhibition of the AKT-GSK3β and ERK1/2 signaling pathways and cell cycle arrest in vitro and in vivo. Taken together, the present study indicates that RV and AC have potential as chemopreventive agents for pancreatic cancer. 相似文献
998.
Selina Greuel Nora Freyer Güngr Hanci Mike Bhme Toshio Miki Johannes Werner Frank Schubert Michael Sittinger Katrin Zeilinger Carl‐Fredrik Mandenius 《Journal of tissue engineering and regenerative medicine》2019,13(7):1203-1216
For clinical and/or pharmaceutical use of human‐induced pluripotent stem cells (hiPSCs), large cell quantities of high quality are demanded. Therefore, we combined the expansion of hiPSCs in closed, perfusion‐based 3D bioreactors with noninvasive online monitoring of oxygen as culture control mechanism. Bioreactors with a cell compartment volume of 3 or 17 ml were inoculated with either 10 × 106 or 50 × 106 cells, and cells were expanded over 15 days with online oxygen and offline glucose and lactate measurements being performed. The CellTiter‐Blue® Assay was performed at the end of the bioreactor experiments for indirect cell quantification. Model simulations enabled an estimation of cell numbers based on kinetic equations and experimental data during the 15‐day bioreactor cultures. Calculated oxygen uptake rates (OUR), glucose consumption rates (GCR), and lactate production rates (LPR) revealed a highly significant correlation (p < 0.0001). Oxygen consumption, which was measured at the beginning and the end of the experiment, showed a strong culture growth in line with the OUR and GCR data. Furthermore, the yield coefficient of lactate from glucose and the OUR to GCR ratio revealed a shift from nonoxidative to oxidative metabolism. The presented results indicate that oxygen is equally as applicable as parameter for hiPSC expansion as glucose while providing an accurate real‐time impression of hiPSC culture development. Additionally, oxygen measurements inform about the metabolic state of the cells. Thus, the use of oxygen online monitoring for culture control facilitates the translation of hiPSC use to the clinical setting. 相似文献
999.
Qin Y Kanasaki Y Takasugi M Shinohara Y Kaminou T Kurosaki M Ogawa T 《Clinical imaging》2012,36(4):379-382
Primary fourth ventricular meningiomas are extremely rare and often misdiagnosed as other tumors. They have no characteristic imaging appearance on computed tomography and magnetic resonance imaging. Therefore, differentiating the lesion from common lesions in the fourth ventricle can be diagnostically challenging. In this report, we present a 25-year-old man with fourth ventricular meningioma and refer to the usefulness of diffusion-weighted imaging and apparent diffusion coefficient measurements for the differential diagnosis of fourth ventricular tumors. 相似文献
1000.
Kawahara S Nakashima Y Oketani H Wada A Fujii M Yamamoto T Mawatari T Motomura G Sato T Akiyama M Fujii T Takamura K Iwamoto Y 《Journal of orthopaedic science》2012,17(3):226-232