全文获取类型
收费全文 | 14556篇 |
免费 | 625篇 |
国内免费 | 104篇 |
专业分类
耳鼻咽喉 | 190篇 |
儿科学 | 374篇 |
妇产科学 | 134篇 |
基础医学 | 1585篇 |
口腔科学 | 392篇 |
临床医学 | 872篇 |
内科学 | 3510篇 |
皮肤病学 | 252篇 |
神经病学 | 1101篇 |
特种医学 | 574篇 |
外科学 | 2883篇 |
综合类 | 45篇 |
预防医学 | 449篇 |
眼科学 | 294篇 |
药学 | 944篇 |
中国医学 | 34篇 |
肿瘤学 | 1652篇 |
出版年
2023年 | 86篇 |
2022年 | 174篇 |
2021年 | 311篇 |
2020年 | 142篇 |
2019年 | 206篇 |
2018年 | 240篇 |
2017年 | 194篇 |
2016年 | 299篇 |
2015年 | 267篇 |
2014年 | 341篇 |
2013年 | 445篇 |
2012年 | 739篇 |
2011年 | 801篇 |
2010年 | 506篇 |
2009年 | 453篇 |
2008年 | 746篇 |
2007年 | 859篇 |
2006年 | 848篇 |
2005年 | 905篇 |
2004年 | 870篇 |
2003年 | 744篇 |
2002年 | 703篇 |
2001年 | 379篇 |
2000年 | 404篇 |
1999年 | 324篇 |
1998年 | 232篇 |
1997年 | 196篇 |
1996年 | 155篇 |
1995年 | 125篇 |
1994年 | 131篇 |
1993年 | 124篇 |
1992年 | 237篇 |
1991年 | 213篇 |
1990年 | 202篇 |
1989年 | 220篇 |
1988年 | 163篇 |
1987年 | 161篇 |
1986年 | 145篇 |
1985年 | 158篇 |
1984年 | 91篇 |
1983年 | 92篇 |
1982年 | 42篇 |
1980年 | 37篇 |
1979年 | 59篇 |
1978年 | 48篇 |
1977年 | 53篇 |
1974年 | 37篇 |
1972年 | 41篇 |
1970年 | 39篇 |
1968年 | 43篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
O Shinohara S Kato H Yabe M Yabe C Kubota R Mitsuda M Kimura 《The American journal of pediatric hematology/oncology》1991,13(3):263-268
Growth of the patients with hematological malignancies, aplastic anemia, Fanconi's anemia, and Wiscott-Aldrich syndrome who had been treated with bone marrow transplantation (BMT) was studied. Fourteen out of 21 patients showed suppression of linear growth after BMT. Recovery of the growth velocity after 1-2 years tended to occur if BMT was performed at younger age. Six of eight patients with chronic graft-versus-host-disease (CGVHD) had impaired growth after BMT, whereas eight of 13 (61%) without CGVHD did. Provocative tests for growth hormone (GH) performed 5-72 months after BMT revealed three boys who showed poor response to more than two different stimuli. Two of these three boys had prolonged suppression of growth. Neither the age at BMT, difference in disease, nor presence of posttransplant growth retardation gave significant difference in the response of GH to provocative tests. It was concluded that approximately two-thirds of marrow-grafted children experienced transient decrease in growth velocity after BMT. 相似文献
33.
34.
Hideaki Anai Yoshihiko Maehara Tatsuo Oshiro Hideo Baba Hiroyuki Orita Toshiro Okuyama Keizo Sugimachi 《Journal of surgical oncology》1993,53(3):204-207
In 268 of the 1,115 patients (24.0%) with gastric cancer who underwent a curative resection in our clinics, the tumor was located in the middle third of the stomach. The clinicopathological features and prognosis of these patients were divided into two groups, according to site of the tumor: anterior wall (n = 58) vs. other sites (n = 210). Clinicopathological factors did not differ between the two groups. The survival time for patients with a tumor in the anterior group was shorter than that for patients with a tumor in other areas (P < 0.05). The five-year survival rate was 79.3% for patients with an anterior tumor and 91.9% for those with a tumor at a different site. A multivariate analysis indicated lymph node metastasis, serosal invasion, and anterior wall location to be independent prognostic factors indicative of a poor prognosis when the tumor was located in the middle third of the stomach. For such patients, close follow-up is needed to detect possible recurrences. © 1993 Wiley-Liss, Inc. 相似文献
35.
Regeneration of defects in articular cartilage in rat knee joints by CCN2 (connective tissue growth factor). 总被引:7,自引:0,他引:7
Takashi Nishida Satoshi Kubota Shunji Kojima Takuo Kuboki Kyouji Nakao Toshihiro Kushibiki Yasuhiko Tabata Masaharu Takigawa 《Journal of bone and mineral research》2004,19(8):1308-1319
CTGF/CCN2, a hypertrophic chondrocyte-specific gene product, possessed the ability to repair damaged articular cartilage in two animal models, which were experimental osteoarthritis and full-thickness defects of articular cartilage. These findings suggest that CTGF/CCN2 may be useful in regeneration of articular cartilage. INTRODUCTION: Connective tissue growth factor (CTGF)/CCN2 is a unique growth factor that stimulates the proliferation and differentiation, but not hypertrophy, of articular chondrocytes in vitro. The objective of this study was to investigate the therapeutic use of CTGF/CCN2. MATERIALS AND METHODS: The effects of recombinant CTGF/CCN2 (rCTGF/CCN2) on repair of damaged cartilage were evaluated by using both the monoiodoacetic acid (MIA)-induced experimental rat osteoarthritis (OA) model and full-thickness defects of rat articular cartilage in vivo. RESULTS: In the MIA-induced OA model, quantitative real-time RT-PCR assays showed a significant increase in the level of CTGF/CCN2 mRNA, and immunohistochemical analysis and in situ hybridization revealed that the clustered chondrocytes, in which clustering indicates an attempt to repair the damaged cartilage, produced CTGF/CCN2. Therefore, CTGF/CCN2 was suspected to play critical roles in cartilage repair. In fact, a single injection of rCTGF/CCN2 incorporated in gelatin hydrogel (rCTGF/CCN2-hydrogel) into the joint cavity of MIA-induced OA model rats repaired their articular cartilage to the extent that it became histologically similar to normal articular cartilage. Next, to examine the effect of rCTGF/CCN2 on the repair of articular cartilage, we created defects (2 mm in diameter) on the surface of articular cartilage in situ and implanted rCTGF/CCN2-hydrogel or PBS-hydrogel therein with collagen sponge. In the group implanted with rCTGF/CCN2-hydrogel collagen, new cartilage filled the defect 4 weeks postoperatively. In contrast, only soft tissue repair occurred when the PBS-hydrogel collagen was implanted. Consistent with these in vivo effects, rCTGF/CCN2 enhanced type II collagen and aggrecan mRNA expression in mouse bone marrow-derived stromal cells and induced chondrogenesis in vitro. CONCLUSION: These findings suggest the utility of CTGF/CCN2 in the regeneration of articular cartilage. 相似文献
36.
37.
Hideaki Ban Hiroyuki Kato Tsutomu Araki Hideaki Fujikura Yoshinari Hasegawa Kyuya Kogure 《Brain research》1994,646(2)
We investigated the effects of age and naftidrofuryl oxalate (Naftidrofuryl), a 5-HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus using quantitative autoradiography. [3H]Quinuclidinyl benzilate (QNB), [3H]cyclohexyl-adenosine (CHA), [3H]MK-801, and [3H]muscimol were used to label muscarinic acetylcholine, adenosine A1, N-methyl-d-aspartate (NMDA), and γ-aminobutyric acid-A (GABAA) receptors, respectively. [3H]PN200-110 labeled L-type Ca2+ channels. [3H]Forskolin, [3H]cyclic adenosine monophosphate (cAMP), [3H]phorbol 12,13-dibutyrate (PDBu), and [3H]inositol 1,4,5-triphosphate (IP3) were used to label adenylate cyclase, cAMP-dependent protein kinase, protein kinase C (PKC), and IP3 receptors, respectively. Approximately 20% reductions in [3H]QNB, [3H]forskolin, and [3H]PDBu binding were observed in the hippocampus of 9-month-old gerbils in comparison with 5-week-old gerbils. Treatment with Naftidrofuryl (10 mg/kg, i.p., once a day for 7 days) ameliorated these reductions. No changes were found in [3H]CHA, [3H]MK-801, [3H]muscimol, [3H]PN200-110, [3H]cAMP, and [3H]IP3 binding. The results suggest that Naftidrofuryl may have beneficial effects on the age-related alterations in signal transmission and transduction systems in the brain. Because the acetylcholine system, adenylate cyclase, and PKC are considered to be involved in learning and memory processes, the result may have clinical implications. 相似文献
38.
Dr. Shosaku Nakahara M.D. Hideaki Itoh M.D. Ryuichi Mibu M.D. Shinichi Ikeda M.D. Yoshihiro Oohata M.D. Kamesaburo Kitano M.D. Yoshihiko Nakamura M.D. 《Diseases of the colon and rectum》1988,31(10):762-766
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line,
using an EEA™ stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following
surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients
could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure
and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct
tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily
by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation
is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is
a functionally acceptable option for low rectal cancer. 相似文献
39.
Regeneration of endothelial cells after balloon denudation of the rabbit carotid artery and changes in responsiveness 总被引:2,自引:0,他引:2
The present experiments were carried out to determine the regrowth of endothelial cells (EC) after balloon denudation of the rabbit carotid artery and the changes in responsiveness of the artery with regenerated EC. Scanning electron microscopic findings revealed that 28.8% of the luminal surface was covered with regenerated EC at week 1. The regrowth of EC proceeded progressively, and a full lining was achieved at week 6. Regenerated EC were morphologically different from native ones; they were elongated (weeks 1 and 2) and irregularly oriented (weeks 4 and 6), and their numbers had significantly increased. Light microscopy revealed the intimal thickening and proliferation of smooth muscle cells. No accumulation of lipids in the vascular wall could be detected at any observation time. The experiments in an organ bath demonstrated that the altered appearance of EC was accompanied by depressed endothelium-dependent relaxations to acetylcholine, ADP and A23187. However, sodium nitroprusside-induced relaxation and contractile responses to noradrenaline, serotonin and histamine remained unchanged in the normal and denuded preparations, indicating that the dysfunction of the endothelium occurs at a time when the ability of the underlying vascular smooth muscle to relax or contract was unchanged. In addition, it is suggested that the impairment of the endothelium-dependent relaxation may be partly due to impairment of the synthesis and/or release of endothelium-derived relaxing factor(s) in EC. 相似文献
40.