全文获取类型
收费全文 | 1462篇 |
免费 | 67篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 37篇 |
儿科学 | 9篇 |
妇产科学 | 11篇 |
基础医学 | 200篇 |
口腔科学 | 65篇 |
临床医学 | 85篇 |
内科学 | 406篇 |
皮肤病学 | 5篇 |
神经病学 | 120篇 |
特种医学 | 60篇 |
外科学 | 234篇 |
综合类 | 3篇 |
一般理论 | 1篇 |
预防医学 | 71篇 |
眼科学 | 14篇 |
药学 | 74篇 |
中国医学 | 2篇 |
肿瘤学 | 139篇 |
出版年
2023年 | 17篇 |
2022年 | 17篇 |
2021年 | 37篇 |
2020年 | 19篇 |
2019年 | 35篇 |
2018年 | 23篇 |
2017年 | 12篇 |
2016年 | 28篇 |
2015年 | 19篇 |
2014年 | 30篇 |
2013年 | 39篇 |
2012年 | 52篇 |
2011年 | 69篇 |
2010年 | 27篇 |
2009年 | 34篇 |
2008年 | 64篇 |
2007年 | 62篇 |
2006年 | 72篇 |
2005年 | 69篇 |
2004年 | 64篇 |
2003年 | 58篇 |
2002年 | 63篇 |
2001年 | 74篇 |
2000年 | 59篇 |
1999年 | 52篇 |
1998年 | 15篇 |
1997年 | 14篇 |
1996年 | 21篇 |
1995年 | 15篇 |
1994年 | 9篇 |
1992年 | 43篇 |
1991年 | 37篇 |
1990年 | 42篇 |
1989年 | 30篇 |
1988年 | 21篇 |
1987年 | 20篇 |
1986年 | 21篇 |
1985年 | 22篇 |
1984年 | 16篇 |
1983年 | 17篇 |
1982年 | 10篇 |
1980年 | 6篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1974年 | 7篇 |
1973年 | 5篇 |
1970年 | 6篇 |
1969年 | 6篇 |
1967年 | 6篇 |
1966年 | 5篇 |
排序方式: 共有1536条查询结果,搜索用时 15 毫秒
21.
Yuriko Masuda Yasunori Nawa Wataru Inami Yoshimasa Kawata 《Biomedical optics express》2015,6(8):3128-3133
Intracellular structures of HeLa cells are observed using a direct electron beam excitation-assisted fluorescence (D-EXA) microscope. In this microscope, a silicon nitride membrane is used as a culture plate, which typically has a low biocompatibility between the sample and the silicon nitride surface to prevent the HeLa cells from adhering strongly to the surface. In this work, the surface of silicon nitride is modified to allow strong cell attachment, which enables high-resolution observation of intracellular structures and an increased signal-to-noise ratio. In addition, the penetration depth of the electron beam is evaluated using Monte Carlo simulations. We can conclude from the results of the observations and simulations that the surface modification technique is promising for the observation of intracellular structures using the D-EXA microscope.OCIS codes: (170.0170) Medical optics and biotechnology, (170.0180) Microscopy 相似文献
22.
Masato Kaku Hiroshi Shimasue Junji Ohtani Shunichi Kojima Hiromi Sumi Hanaka Shikata Shotoku Kojima Masahide Motokawa Tahsin Raquib Abonti Toshitsugu Kawata Kazuo Tanne Kotaro Tanimoto 《The Angle orthodontist》2015,85(3):518
This case report describes the treatment of a skeletal Class III malocclusion with autotransplantation of a cryopreserved tooth. To gain an esthetic facial profile and good occlusion, extraction of bimaxillary premolars and surgical therapy were chosen. The patient had chronic apical periodontitis on the lower left first molar. Although she did not feel any pain in that region, the tooth was considered to have a poor prognosis. Therefore, we cryopreserved the extracted premolars to prepare for autotransplantation in the lower first molar area because the tooth would probably need to be removed in the future. The teeth were frozen by a programmed freezer with a magnetic field (CAS freezer) that was developed for tissue cryopreservation and were cryopreserved in −150°C deep freezer. After 1.5 years of presurgical orthodontic treatment, bilateral sagittal split ramus osteotomy was performed for mandible setback. Improvement of the facial profile and the occlusion were achieved in the retention phase. Six years after the initial visit, the patient had pain on the lower left first molar, and discharge of pus was observed, so we extracted the lower left first molar and autotransplanted the cryopreserved premolar. Three years later, healthy periodontium was observed at the autotransplanted tooth. This case report suggests that long-term cryopreservation of teeth by a CAS freezer is useful for later autotransplantation, and this can be a viable technique to replace missing teeth. 相似文献
23.
24.
Estrogen and non-feminizing estrogen for Alzheimer's disease 总被引:3,自引:0,他引:3
Honjo H Iwasa K Fushiki S Hosoda T Tatsumi H Mihara M Hirasugi Y Oida M Kariya K Kikuchi N Kawata M 《Endocrine journal》2003,50(4):361-367
The preventive effect of estrogen on Alzheimer's disease (AD) has become clearer with many epidemiological reports. However, the therapeutic effects of estrogen have been controversial until now. In our trials, estrogen treatment showed a beneficial therapeutic effect for women with mild to moderate AD. Improvement of cognitive function was recognized during the third week from the beginning of administration and maintained as long as estrogen treatment continued. The longer the duration of HRT, the more HRT is useful for the prevention and therapy of AD. However, in most cases, administration of estrogen is discontinued because of the adverse effects on the uterus and breast. J 861 is a derivative of estradiol-17alpha, which has little effect on the sexual organs. The effects of estradiol-17beta (E2) and J 861 on neuronal function and vascular factors were investigated. J 861 was suggested to prevent both the intracellular calcium increase and peroxidation induced by amyloid beta (Abeta), more effectively than E2. The effect of J 861 may be related with both the direct non-genomic and the ER-mediated systems. J 861 showed neurotrophic effects like E2. J 861 inhibited the adhesion of monocytes to vascular endothelium, more effectively than E2. Also, J 861 suppressed the expression of adhesive factors, such as E-selectin and intercellular cell adhesion molecule-1 (ICAM-1), more effectively than E2. 相似文献
25.
Ando Y Yang GX Tsuda M Kawata K Zhang W Nakajima T Tsuneyama K Leung P Lian ZX Okazaki K Ridgway WM Norman GL Ansari AA He XS Coppel RL Gershwin ME 《Hepatology (Baltimore, Md.)》2012,56(4):1418-1426
Dominant negative form of transforming growth factor beta receptor type II (dnTGFβRII) mice, expressing a dominant negative form of TGFβ receptor II under control of the CD4 promoter, develop autoimmune colitis and cholangitis. Deficiency in interleukin (IL)-12p40 lead to a marked diminution of inflammation in both the colon and the liver. To distinguish whether IL-12p40 mediates protection by the IL-12 or IL-23 pathways, we generated an IL-23p19(-/-) dnTGFβRII strain deficient in IL-23, but not in IL-12; mice were longitudinally followed for changes in the natural history of disease and immune responses. Interestingly, IL-23p19(-/-) mice demonstrate dramatic improvement in their colitis, but no changes in biliary pathology; mice also manifest reduced T-helper (Th)17 cell populations and unchanged IFN-γ levels. We submit that the IL-12/Th1 pathway is essential for biliary disease pathogenesis, whereas the IL-23/Th17 pathway mediates colitis. To further assess the mechanism of the IL-23-mediated protection from colitis, we generated an IL-17A(-/-) dnTGFβRII strain deficient in IL-17, a major effector cytokine produced by IL-23-dependent Th17 cells. Deletion of the IL-17A gene did not affect the severity of either cholangitis or colitis, suggesting that the IL-23/Th17 pathway contributes to colon disease in an IL-17-independent manner. These results affirm that the IL-12/Th1 pathway is critical to biliary pathology in dnTGFβRII mice, whereas colitis is caused by a direct effect of IL-23. (HEPATOLOGY 2012). 相似文献
26.
Masahide Motokawa Natsumi Tsuka Masato Kaku Toshitsugu Kawata Tadashi Fujita Junji Ohtani Yayoi Matsuda Akiko Terao Kazuo Tanne 《Archives of oral biology》2013,58(1):35-41
ObjectiveThe purpose of this study was to clarify the interaction of vascular endothelial growth factors (VEGFs)-C and -D with cell surface foetal liver kinase-1 (Flk-1) and fms-like tyrosine kinase-4 (Flt-4) receptors in the induction and activity of osteoclasts in cultured human peripheral blood mononuclear cells (PBMCs).DesignPBMCs were cultured on chamber slides or on ivory discs for 2 or 3 weeks in the presence of macrophage-colony stimulating factor (M-CSF), VEGF-A, -C or -D, or placental growth factor (PlGF) with or without receptor activator of nuclear factor kappa-B ligand (RANKL). The number of osteoclasts in each group was counted and the area of ivory resorption was measured. In addition, osteoclast differentiation was further analysed under the same conditions, but with the addition of specific neutralizing antibodies against Flk-1 and Flt-4.ResultsRANKL was essential for the induction of osteoclasts in PBMCs. However, significant differences were found in the number of osteoclasts induced by VEGF-A, -C, -D or M-CSF with RANKL compared with control groups lacking or containing RANKL. Blocking of either Flk-1 or Flt-4 resulted in a reduction in the enhancement of osteoclast differentiation in PBMCs by VEGF-C or -D with RANKL. The osteoclasts induced by VEGF-A, -C, -D or M-CSF with RANKL formed significantly larger resorption lacunae than those formed by osteoclasts induced by RANKL alone.ConclusionsThis study showed that VEGF-C and -D play a role in the induction of osteoclast differentiation through both Flk-1 and Flt-4 receptors and influence the area of the ivory resorption in PBMCs. 相似文献
27.
28.
Motokawa M Tsuka N Kaku M Kawata T Fujita T Ohtani J Matsuda Y Terao A Tanne K 《Archives of oral biology》2012,57(4):352-356
ObjectiveExpression of osteoclasts in osteopetrotic (op/op) mice is substantially reduced by the absence of functional macrophage colony-stimulating factor (M-CSF). However, it has been reported that osteoclasts do gradually appear in the bones of op/op mice and spontaneously correct the osteopetrosis.DesignAge-related production of osteoclasts and the changes of serum levels of vascular endothelial growth factor (VEGF) and receptor activator for nuclear factor (NF)-κB ligand (RANKL) in op/op mice were examined.ResultsThe number of femoral osteoclasts, and the serum levels of VEGF, both gradually increased in op/op mice after birth and reached a peak in 120- and 60-day-old mice, respectively. However, the serum levels of RANKL showed an inverse relationship to osteoclast number.ConclusionsThese findings suggest that the appearance of osteoclasts may be influenced by the serum levels of VEGF and that the serum levels of RANKL may be influenced by the appearance of osteoclasts. 相似文献
29.
Yukie Hirahara Ken Ichi Matsuda Hisao Yamada Akira Saitou Shinsuke Morisaki Keiko Takanami Joan M. Boggs Mitsuhiro Kawata 《Glia》2013,61(3):420-431
Estrogen exerts neuroprotective and promyelinating actions. The therapeutic effect has been shown in animal models of multiple sclerosis, in which the myelin sheath is specifically destroyed in the central nervous system. However, it remains unproven whether estrogen is directly involved in remyelination via the myelin producing cells, oligodendrocytes, or which estrogen receptors are involved. In this study, we found that the membrane‐associated estrogen receptor, the G protein‐coupled receptor 30 (GPR30), also known as GPER, was expressed in oligodendrocytes in rat spinal cord and corpus callosum. Moreover, GPR30 was expressed throughout oligodendrocyte differentiation and promyelinating stages in primary oligodendrocyte cultures derived from rat spinal cords and brains. To evaluate the role of signaling via GPR30 in promyelination, a specific agonist for GPR30, G1, was administered to a rat model of demyelination induced by cuprizone treatment. Histological examination of the corpus callosum with oligodendrocyte differentiation stage‐specific markers showed that G1 enhanced oligodendrocyte maturation in corpus callosum of cuprizone‐treated animals. It also enhanced oligodendrocyte ensheathment of dorsal root ganglion (DRG) neurons in co‐culture and myelination in cuprizone‐treated animals. This study is the first evidence that GPR30 signaling promotes remyelination by oligodendrocytes after demyelination. GPR30 ligands may provide a novel therapy for the treatment of multiple sclerosis. © 2012 Wiley Periodicals, Inc. 相似文献
30.
Yasue Nishii Shinnosuke Kawata Naoto Fujita Koichi Tomoda Hidetaka Imagita 《Sport Sciences for Health》2016,12(1):91-97