全文获取类型
收费全文 | 4503篇 |
免费 | 233篇 |
国内免费 | 49篇 |
专业分类
耳鼻咽喉 | 68篇 |
儿科学 | 71篇 |
妇产科学 | 93篇 |
基础医学 | 618篇 |
口腔科学 | 110篇 |
临床医学 | 414篇 |
内科学 | 763篇 |
皮肤病学 | 150篇 |
神经病学 | 322篇 |
特种医学 | 203篇 |
外科学 | 577篇 |
综合类 | 32篇 |
一般理论 | 3篇 |
预防医学 | 243篇 |
眼科学 | 67篇 |
药学 | 576篇 |
中国医学 | 110篇 |
肿瘤学 | 365篇 |
出版年
2023年 | 31篇 |
2022年 | 113篇 |
2021年 | 183篇 |
2020年 | 90篇 |
2019年 | 116篇 |
2018年 | 143篇 |
2017年 | 105篇 |
2016年 | 140篇 |
2015年 | 195篇 |
2014年 | 255篇 |
2013年 | 277篇 |
2012年 | 388篇 |
2011年 | 404篇 |
2010年 | 222篇 |
2009年 | 167篇 |
2008年 | 269篇 |
2007年 | 256篇 |
2006年 | 225篇 |
2005年 | 190篇 |
2004年 | 165篇 |
2003年 | 140篇 |
2002年 | 107篇 |
2001年 | 97篇 |
2000年 | 78篇 |
1999年 | 82篇 |
1998年 | 33篇 |
1997年 | 18篇 |
1996年 | 22篇 |
1995年 | 11篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 31篇 |
1991年 | 29篇 |
1990年 | 25篇 |
1989年 | 22篇 |
1988年 | 10篇 |
1987年 | 12篇 |
1986年 | 5篇 |
1985年 | 17篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1979年 | 5篇 |
1974年 | 8篇 |
1972年 | 5篇 |
1971年 | 8篇 |
1970年 | 4篇 |
1969年 | 6篇 |
1968年 | 14篇 |
1967年 | 5篇 |
1966年 | 4篇 |
排序方式: 共有4785条查询结果,搜索用时 15 毫秒
101.
Jin-Hwa Jang Ji-Hae Lee Mi-Kyung Je Myeong-Ji Cho Young Mee Bae Hyeon Seok Son Insung Ahn 《Yebang Ŭihakhoe chi》2015,48(4):203-215
Objectives:
This study was performed to investigate the relationship between the incidence of national notifiable infectious diseases (NNIDs) and meteorological factors, air pollution levels, and hospital resources in Korea.Methods:
We collected and stored 660 000 pieces of publicly available data associated with infectious diseases from public data portals and the Diseases Web Statistics System of Korea. We analyzed correlations between the monthly incidence of these diseases and monthly average temperatures and monthly average relative humidity, as well as vaccination rates, number of hospitals, and number of hospital beds by district in Seoul.Results:
Of the 34 NNIDs, malaria showed the most significant correlation with temperature (r=0.949, p<0.01) and concentration of nitrogen dioxide (r=-0.884, p<0.01). We also found a strong correlation between the incidence of NNIDs and the number of hospital beds in 25 districts in Seoul (r=0.606, p<0.01). In particular, Geumcheon-gu was found to have the lowest incidence rate of NNIDs and the highest number of hospital beds per patient.Conclusions:
In this study, we conducted a correlational analysis of public data from Korean government portals that can be used as parameters to forecast the spread of outbreaks. 相似文献102.
Usefulness of optical coherence tomography to detect central serous chorioretinopathy in monkeys
下载免费PDF全文
![点击此处可从《Journal of applied toxicology : JAT》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Hyun‐Kyu Park Woori Jo Hyun‐Ji Choi Bongcheol Kim Gilnam Lee Jeongbeob Seo Suk Young Cho Choung‐Soo Kim Eun Kyung Choi Jung Jin Hwang Joo Yong Lee Young Hee Yoon Woo‐Chan Son 《Journal of applied toxicology : JAT》2015,35(2):199-204
Many systemic drugs can induce ocular toxicity and several ocular side‐effects have been identified in clinical studies. However, it is difficult to detect ocular toxicity in preclinical studies because of the lack of appropriate evaluation methods. Optical coherence tomography (OCT) is useful because it can provide real‐time images throughout a study period, whereas histopathology only provides images of sacrificed animals. Using OCT alongside histopathology, attempts were made to find effective approaches for screening of drug‐induced ocular toxicity in monkeys. Such approaches could be used in preclinical studies prior to human trials. Six male cynomolgus monkeys (Macaca fascicularis Raffles) were orally administered one of six candidate MAPK/ERK kinase (MEK) inhibitors. Central serous chorioretinopathy, a known side‐effect of such inhibitors, was identified in four monkeys by OCT. Artifacts generated during tissue processing meant that histopathology could not detect edematous changes. Thus, OCT is a useful tool to detect ocular toxicity which cannot be detected by histopathology in preclinical studies. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
103.
104.
YongSung Kwon Shivshankar Chaudhari ChaEun Kim DaHae Son JiHwan Park MyungJun Moon MinYoung Shon YouIn Park SeungEun Nam 《RSC advances》2018,8(37):20669
Ag-exchanged NaY zeolite (Ag-NaZ) particles were prepared by ion exchange and introduced to a polyvinyl alcohol (PVA) membrane cross-linked with polyacrylic acid (PAA) for the pervaporation dehydration of an isopropanol (IPA) aqueous mixture. The Ag-exchanged NaY zeolite particles were characterized by FE-SEM, EDS, BET, and XRD studies. The prepared Ag-NaZ-loaded PVA/PAA composite membrane was characterized by FE-SEM, XRD, a swelling study, and contact angle measurements. Pervaporation characteristics were investigated in terms of Ag-NaZ concentrations within PVA/PAA membranes using diverse feed solution conditions. The preferential sorption of IPA/water mixtures for Ag-NaZ-introduced membranes were also determined by calculating the apparent activation energies of IPA and water permeation, respectively. As a result, flux and selectivity increased with the Ag-NaZ concentration to 5 wt% in the membrane. Optimum pervaporation performance was observed in a 5 wt% Ag-NaZ-incorporated membrane with a flux equal to 0.084 kg m−2 h−1 and a separation factor of 2717.9 at 40 °C from an 80 wt% IPA aqueous feed solution.Ag-exchanged NaY zeolite (Ag-NaZ) particles were prepared by ion exchange and introduced to a polyvinyl alcohol (PVA) membrane cross-linked with polyacrylic acid (PAA) for the pervaporation dehydration of an isopropanol (IPA) aqueous mixture. 相似文献
105.
Chung YS Chung YW Moon SY Yoon SM Kim MJ Kim KO Park CH Hahn T Yoo KS Park SH Kim JH Park CK 《World journal of gastroenterology : WJG》2008,14(6):948-950
Foreign bodies in the colon are encountered with increasing frequency, but only sporadic reports concerning their management have appeared in the literature. While most ingested foreign bodies usually pass through the gastrointestinal tract uneventfully, sharp foreign bodies such as toothpicks infrequently cause intestinal perforation and may even result in death. We report our experience with a patient with a sigmoid colon pseudodiverticulum formation, a complication of accidental ingestion of a toothpick that was diagnosed and successfully managed colonoscopically. 相似文献
106.
J A van Son U Steinseifer H Reul E Knott J G Vincent L K Lacquet 《The Thoracic and cardiovascular surgeon》1989,37(5):288-293
The vulnerability of the Medtronic-Hall, Bj?rk-Shiley Monostrut, Duromedics, and St. Jude Medical valves to occluder immobilization by sutures was determined under static and pulsatile flow conditions. Variables were cardiac output, cross-sectional diameter of suture, type of suture (braided versus monofilament) and position of the offending suture along the circumference of the valve ring. Under static conditions, pressures, ranging from 40 to 340 mmHg and 10 to 170 mmHg, were required to decompress obstructed Medtronic-Hall and Bj?rk-Shiley Monostrut valves, respectively. As a result of different design characteristics and different occluder/orifice clearances the Medtronic-Hall valve showed its maximum opening pressure in case of interference with sutures at the axis of symmetry in both minor and major orifices, whereas for the Bj?rk-Shiley Monostrut valve this was reached in the minor orifice. Under pulsatile flow conditions, in case of interference with Prolene 2-0 suture, the Duromedics valve showed irregularly delayed opening and an opening pressure difference of 50 mmHg at a cardiac output of 8 L/min, whereas leaflet motion and pressure difference in the St. Jude Medical valve were undisturbed under similar conditions. The necessary pressure difference for opening the Medtronic Hall valve reached 44mmHg at a cardiac output of 8 L/min. High and low risk of extrinsic leaflet obstruction in the Duromedics and St. Jude Medical valves, respectively, is related to the design of the hinge mechanisms and the wedge angle of their leaflets (2 degrees versus 25 degrees). Precautionary principles in implantation of prosthetic heart valves are stressed to prevent the potentially lethal complication of occluder immobilization.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
107.
TNF-alpha has significant inhibitory effects on steroidogenesis and folliculogenesis and is associated with several inflammatory responses. Because ovulation is an inflammatory reaction, the effects of TNF on the family of acute-phase proteins in granulosa cells were investigated. Granulosa cells from immature mice at 28 d of age were cultured in the presence of 10 ng TNF/ml for 24 h. Serum amyloid A3 (SAA3), a main acute-phase protein, was induced by TNF in granulosa cells. The other isoforms of serum amyloid proteins SAA1, SAA2, and SAA4 were neither expressed in granulosa cells nor induced by TNF. TNF did not induce SAA3 mRNA in granulosa cells from TNF receptor type 1 (TNFR1) knockout mice, although SAA3 mRNA was induced within 3 h after TNF treatment in wild-type cells. Two SAA3 promoters, -617/+73 and -198/+73, were responsive to TNF and to p65, a component of the TNF signaling molecule nuclear factor (NF)-kappaB. The -106/+73 promoter of SAA3 lacking a NF-kappaB-like site was not responsive to TNF or p65. In granulosa cells from TNFR1 knockout mice, the SAA3 promoter (-198/+73) was responsive to transfection with the p65 component of NF-kappaB, but neither TNF treatment nor overexpression of the p50 component of NF-kappaB increased promoter activity. Similar results were observed in the murine ovarian granulosa tumor cell line (OV3121-1). Overexpression of the inhibitor of NF-kappaB (called IkappaB) blocked SAA3 promoter activity induced by TNF and by p65 in OV3121-1 cells. Closer analysis of deletion mutants of the SAA3 promoter revealed the necessity of a NF-kappaB like site for responsiveness to TNF in the OV3121-1 cells. TNF rapidly increased p65 in OV3121-1 nuclei when compared with controls not treated with TNF. TNF also increased phospho-IkB and SAA3 in whole-cell homogenates as determined by Western blots. Thus, TNF likely increased SAA3 promoter activity and protein by activating NF-kappaB signaling via TNFR1 in mouse granulosa cells. SAA3 is a novel gene in granulosa cells with yet unknown functions in the ovary. 相似文献
108.
Changes in autoimmune thyroid disease following allogeneic bone marrow transplantation 总被引:1,自引:0,他引:1
Lee WY Oh ES Min CK Kim DW Lee JW Kang MI Min WS Cha BY Lee KW Son HY Kang SK Kim CC 《Bone marrow transplantation》2001,28(1):63-66
Autoimmune diseases can be transmitted and eliminated by bone marrow transplantation (BMT). There have been several cases of autoimmune thyroid disease (AITD) occurring after BMT, but AITD remission has been rarely reported. We present four cases in which the remission or transfer of AITD occurred after an allogeneic BMT. Two patients with severe aplastic anemia (SAA) showed evidence of remission of Hashimoto's thyroiditis which they had before allogeneic BMT. One patient with SAA, which developed during treatment with propylthiouracil for Graves' disease, underwent allogeneic BMT and showed evidence of Graves' disease remission following BMT. In one patient, new AITD occurred after an allogeneic BMT from an HLA-matched sibling who already had AITD. These cases support the evidence that the immune system is newly reconstituted after BMT, and severe autoimmune disease can be an indication for BMT. To fully understand the real changes in autoimmune status after BMT, long-term prospective studies are necessary. 相似文献
109.
Maaike B. van Werkhoven Jeffrey Damman Mohamed R. Daha Christina Krikke Harry van Goor Willem J. van Son Jan-Luuk Hillebrands Marcory C.R.F. van Dijk Marc A.J. Seelen 《Molecular immunology》2013,53(3):237-245
AimsThe complement system, and especially C5a, plays an important role in the pathophysiology of renal diseases and post-transplant renal injury. The two receptors for C5a are C5a receptor (C5aR) and C5a-like-receptor-2 (C5L2). Only renal C5aR expression has been reported, although exact localization and alterations in expression after transplantation are unknown.Materials and resultsRenal C5aR and C5L2 expression and localization were analyzed immunohistochemically. C5aR and C5L2 expression was analyzed in human kidney biopsies obtained from living donors and patients suffering from acute tubular necrosis, acute cellular and vascular rejection or IF/TA.C5aR was expressed in the thick ascending limb of Henle's loop and first part of the distal convoluted tubule (DCT). Under inflammatory conditions, C5aR was de novo expressed in proximal tubuli. C5L2 was expressed in the kidney and localized to DCT1, DCT2 and connecting tubule. Persistent distal tubular expression of both receptors was demonstrated after renal transplantation.ConclusionsThis study shows distinct renal expression patterns for C5aR and C5L2. Our findings suggest a functional role for renal C5L2 rather than being a C5a decoy receptor. Future studies focusing on renal C5a–C5aR interaction should take differential C5aR and C5L2 expression into account, alongside abundant C5aR expression on infiltrating cells. 相似文献