全文获取类型
收费全文 | 13142篇 |
免费 | 915篇 |
国内免费 | 170篇 |
专业分类
耳鼻咽喉 | 239篇 |
儿科学 | 226篇 |
妇产科学 | 164篇 |
基础医学 | 2357篇 |
口腔科学 | 130篇 |
临床医学 | 1175篇 |
内科学 | 2529篇 |
皮肤病学 | 584篇 |
神经病学 | 800篇 |
特种医学 | 917篇 |
外科学 | 1315篇 |
综合类 | 55篇 |
一般理论 | 1篇 |
预防医学 | 515篇 |
眼科学 | 358篇 |
药学 | 1499篇 |
中国医学 | 214篇 |
肿瘤学 | 1149篇 |
出版年
2024年 | 11篇 |
2023年 | 96篇 |
2022年 | 347篇 |
2021年 | 455篇 |
2020年 | 266篇 |
2019年 | 362篇 |
2018年 | 408篇 |
2017年 | 367篇 |
2016年 | 583篇 |
2015年 | 796篇 |
2014年 | 929篇 |
2013年 | 972篇 |
2012年 | 1374篇 |
2011年 | 1202篇 |
2010年 | 878篇 |
2009年 | 657篇 |
2008年 | 824篇 |
2007年 | 772篇 |
2006年 | 634篇 |
2005年 | 596篇 |
2004年 | 435篇 |
2003年 | 346篇 |
2002年 | 297篇 |
2001年 | 85篇 |
2000年 | 66篇 |
1999年 | 40篇 |
1998年 | 47篇 |
1997年 | 52篇 |
1996年 | 37篇 |
1995年 | 28篇 |
1994年 | 29篇 |
1993年 | 23篇 |
1992年 | 25篇 |
1991年 | 22篇 |
1990年 | 18篇 |
1989年 | 21篇 |
1988年 | 24篇 |
1987年 | 12篇 |
1986年 | 15篇 |
1985年 | 18篇 |
1984年 | 8篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1971年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
11.
BACKGROUND: The phenomenon of wound contraction results in a decrease in wound size and a healed scar significantly smaller than the original defect. OBJECTIVE: This study was undertaken (1) to determine the amount of wound contraction in Mohs surgery defects allowed to heal by second intention, (2) to evaluate for regional differences in wound contraction based on the facial anatomic zones for second intention healing described by Zitelli, and (3) to determine whether regional differences in wound contraction account for observed differences in cosmetic outcome. METHODS: One hundred sixty secondarily healed Mohs surgery defects limited to the head and neck having a wound age of greater than 12 weeks in 102 consecutively examined patients were carefully measured with a tissue caliper. The percent wound contraction was calculated and compared for each Zitelli anatomic subunit. The final shape of the wound (quantitatively described) and the cosmetic acceptability (subjectively rated by the patient and examiner) were also compared with the percent wound contraction for each anatomic area. RESULTS: Both NEET (concave surface of the nose, eye, ear, and temple) and FAIR (forehead, antihelix, eyelids, and the remainder of the nose, lips, and cheeks) areas were identical in terms of mean wound contraction (74%), cosmetic acceptability (97%), and conversion to a wound shape with a ratio of maximal length to width of greater than 3.0 (fusiform and linear shapes) (52%). NOCH areas (convex surface of the nose, oral lips, cheeks and chin, and the helix of the ear) demonstrated less wound contraction (66%), cosmetic acceptability (78%), and fusiform-linear conversion (29%). Subset differences and variables that appear to influence wound contraction are discussed. Secondarily healed wounds in areas with one or more positive contraction variables contract 75%, whereas defects in areas with negative contraction variables contract 55%. CONCLUSIONS: Regional differences in wound contraction of secondarily healed head and neck wounds exist and account for some differences in cosmetic acceptability. Scar location, regardless of the degree of wound contraction, is the most important factor for the final cosmetic outcome. 相似文献
12.
Hyun Chul Kim Sang Woo Nam Yong Keun Cho Hey Jin Jeong Se In Kim Seong Hun Kim Chul Min An In Hee Kim Sang Wook Kim Seung Ok Lee Soo Teik Lee 《Taehan Sohwagi Hakhoe chi》2006,47(3):233-237
Although adenocarcinoma is a well known complication of chronic inflammatory bowel disease, primary gastrointestinal lymphoma occurring in Crohn's disease is rare. A 40-year-old man with 10 year-history of Crohn's disease had multiple longitudinal ulcerative lesions on descending colon in follow-up colonoscopic examination. Microscopic examination of proximal descending colon revealed peripheral T cell lymphoma and other site of the descending colon was consistent with Crohn's disease. The patient reached complete remission of malignant lymphoma after three cycles of combined chemotherapy. He has been well for 10 months with sulfasalazine maintenance therapy but was admitted to the hospital due to spontaneous bowel perforation of ascending colon. Right hemicolectomy was done, but the patient died of post-surgical recurrent mesenteric abscess and sepsis. To the best of our knowledge, this is the first case of Non-Hodgkin's lymphoma complicating Crohn's disease in Korea which was confirmed by immunohistochemical studies. 相似文献
13.
Si Chan Sung Yun Hee Chang Jong Soo Woo 《European journal of cardio-thoracic surgery》2007,31(4):742-743
We developed a technique of translocation of the pulmonary artery anterior to the ascending aorta without transection of the aorta in the repair of tetralogy of Fallot with absent pulmonary valve. Our technique includes detachment of the main pulmonary artery (MPA) from the pulmonary annulus, vertical division of the MPA, anterior translocation of the pulmonary artery with patch augmentation between the vertically divided MPA. 相似文献
14.
Ei Tae Kim Lee Hoo Kim Jung Il Lee Hee Seung Chin 《Japanese journal of ophthalmology》2009,53(6):598-602
Background
To assess the nature, incidence, and risk factors of retinopathy associated with pegylated interferon and ribavirin combination therapy in chronic hepatitis C patients. 相似文献15.
PCBs with the highest vapor pressures (fewest chlorines) in Aroclors 1016, 1242, 1254 and 1268 were enriched in the vapor phase relative to the original Aroclor during volatilization from a glass surface for up to 8 hr. PCBs with the lowest vapor pressures (most highly chlorinated) were enriched in the corresponding residue. Thus, visual matching of gas chromatograms with those of Aroclor standards may not be sufficient to identify a specific Aroclor since the past history of a sample is often unknown. The enrichment also was detected using isomeric classes, but not using total chlorine content. The perchlorination method and the Webb-McCall method using all chromatographic peaks agreed quantitatively; this was not always so for the NIOSH multiple peaks and the Webb-McCall methods. 相似文献
16.
A method for dynamic imaging in MRI is presented that enables the acquisition of a series of images with both high temporal and high spatial resolution. The technique, which is based on the projection reconstruction (PR) imaging scheme, utilizes distinct data acquisition and reconstruction strategies to achieve this simultaneous capability. First, during acquisition, data are collected in multiple undersampled passes, with the view angles interleaved in such a way that those of subsequent passes bisect the views of earlier ones. During reconstruction, these views are weighted according to a previously described k-space weighted image contrast (KWIC) technique that enables the manipulation of image contrast by selective filtering. Unlike conventional undersampled PR methods, the proposed dynamic KWIC technique does not suffer from low image SNR or image degradation due to streaking artifacts. The effectiveness of dynamic KWIC is demonstrated in both simulations and in vivo, high-resolution, contrast-enhanced imaging of breast lesions. 相似文献
17.
Yang Hee Lee Ihn Rhan Lee Won Sick Won Chung Hee Park 《Archives of pharmacal research》1988,11(3):247-249
18.
Growth factor-dependent activation of the MAPK pathway in human pancreatic cancer: MEK/ERK and p38 MAP kinase interaction in uPA synthesis 总被引:3,自引:0,他引:3
Increased expression of the hepatocyte growth factor (HGF) receptor (c-met) and urokinase type plasminogen (uPA) correlated
with the development and metastasis of cancers. To investigate the role of HGF/c-met signaling on metastasis in cancer cells
stimulated with HGF, we examined the effects of a specific MEK1 inhibitor (PD98059) and a p38 MAP kinase inhibitor (SB203580)
on HGF-induced uPA expression in pancreatic cancer cell lines, L3.6PL and IMIM-PC2. Pretreatment of PD98059 decreased HGF-mediated
phosphorylation of extracellular receptor kinase (ERK), uPA secretion and expression of matrix metalloproteinases (MMP-2 and
MMP-9) in a dose-dependent manner. In contrast, SB203580 pretreatment increased HGF-stimulated ERK phosphorylation, uPA secretion
and expression of MMPs. SB203580 also reversed the inhibition of HGF-mediated ERK activation and uPA secretion in the PD98059-pretreated
cells. These results suggest that ERK activation by HGF might play important roles in the metastasis of pancreatic cancer
and the p38 MAPK pathway also involved in the HGF-mediated uPA secretion and metastasis by regulation of ERK pathway.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
19.
The application of molecular techniques to solid tumors 总被引:1,自引:0,他引:1
Recent developments in the field of molecular biology including the sequencing of the human genome and related high throughput methodologies are presenting the diagnostic pathologist with new opportunities to expand our understanding of human disease. These techniques enable the comprehensive assessment of molecular alterations with cell populations of interest, including cancer. It will be necessary for the diagnostic pathologist to become familiar with these techniques to effectively translate their potential into the clinical environment. 相似文献
20.
Detection of YMDD motif mutants by oligonucleotide chips in lamivudine-untreated patients with chronic hepatitis B virus infection 总被引:9,自引:0,他引:9
Heo J Cho M Kim HH Shin YM Jang HJ Park HK Kim CM Kim GH Kang DH Song GA Yang US 《Journal of Korean medical science》2004,19(4):541-546
Lamivudine, a nucleoside analogue, has been used widely as an effective antiviral agent for the treatment of patients with chronic hepatitis B virus (HBV) infection. However, the YMDD motif mutation of HBV polymerase resistant to lamivudine occurs very frequently after long term therapy. We developed an oligonucleotide chip for the detection of YMDD motif mutants resistant to lamivudine and investigated the prevalence of the mutants in patients with chronic HBV infection who had not been treated by lamivudine before. Forty patients who had not been treated with lamivudine were included in this study. Serum samples were tested by the oligonucleotide chips designed for detection of wild-type YMDD motif, M552V and M552I. Samples were confirmed by restriction fragment length polymorphism (RFLP) and direct sequencing. M552I mutants were detected by the oligonucleotide chips in 7.5% (3/40) of chronic HBV infected patients (2 chronic hepatitis and 1 cirrhosis). The results were in accordance with those of RFLP. YMDD motif mutants occur as natural genome variabilities in patients with chronic HBV infection who had not been treated with lamivudine before. Oligonucleotide chip technology is a reliable and useful diagnostic tool for the detection of mutants resistant to antiviral therapy in chronic HBV infection. 相似文献