全文获取类型
收费全文 | 6838篇 |
免费 | 306篇 |
国内免费 | 74篇 |
专业分类
耳鼻咽喉 | 111篇 |
儿科学 | 124篇 |
妇产科学 | 257篇 |
基础医学 | 518篇 |
口腔科学 | 132篇 |
临床医学 | 602篇 |
内科学 | 1912篇 |
皮肤病学 | 86篇 |
神经病学 | 366篇 |
特种医学 | 289篇 |
外科学 | 1379篇 |
综合类 | 26篇 |
预防医学 | 308篇 |
眼科学 | 146篇 |
药学 | 309篇 |
中国医学 | 3篇 |
肿瘤学 | 650篇 |
出版年
2024年 | 3篇 |
2023年 | 47篇 |
2022年 | 132篇 |
2021年 | 239篇 |
2020年 | 130篇 |
2019年 | 195篇 |
2018年 | 206篇 |
2017年 | 146篇 |
2016年 | 164篇 |
2015年 | 166篇 |
2014年 | 298篇 |
2013年 | 332篇 |
2012年 | 587篇 |
2011年 | 603篇 |
2010年 | 363篇 |
2009年 | 331篇 |
2008年 | 571篇 |
2007年 | 581篇 |
2006年 | 480篇 |
2005年 | 405篇 |
2004年 | 350篇 |
2003年 | 314篇 |
2002年 | 259篇 |
2001年 | 34篇 |
2000年 | 13篇 |
1999年 | 31篇 |
1998年 | 52篇 |
1997年 | 26篇 |
1996年 | 30篇 |
1995年 | 23篇 |
1994年 | 18篇 |
1993年 | 11篇 |
1992年 | 10篇 |
1991年 | 5篇 |
1990年 | 11篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 11篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1974年 | 4篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有7218条查询结果,搜索用时 15 毫秒
11.
Inge Reimann Dimitrios Vittas Steen Levin Nielsen Eiliv Svalastoga 《Acta orthopaedica》1989,60(2):185-187
The resorption pattern of synovial fluid through the lymphatic system from normal and synovitic knee joints in rabbits was studied with 99mHechnetium-rhenium-sulfur colloid injected intraarticularly and monitored for 14 hours with a gamma camera.
On the normal side the regional lymph nodes were visualized after I hour and after 14 hours still 75 percent activity remained in the knee. In the synovitic knees no lymphatic transport could be detected; and the radiotracer was unstable with rapid liberation of technetium, which was excreted in the urine. This radiolysis was not found in vitro in synovitic joint fluid.
The lymphatic transport from normal rabbit knees is low. We found a clear difference in lymphatic transport between normal and synovitic knee joints. 相似文献
On the normal side the regional lymph nodes were visualized after I hour and after 14 hours still 75 percent activity remained in the knee. In the synovitic knees no lymphatic transport could be detected; and the radiotracer was unstable with rapid liberation of technetium, which was excreted in the urine. This radiolysis was not found in vitro in synovitic joint fluid.
The lymphatic transport from normal rabbit knees is low. We found a clear difference in lymphatic transport between normal and synovitic knee joints. 相似文献
12.
Nakopoulou L Tsirmpa I Giannopoulou I Trafalis D Katsarou S Davaris P 《Cancer Genetics and Cytogenetics》2002,134(2):127-132
Breast carcinoma is a genetically and phenotypically heterogeneous disease and is frequently associated with nonrandom chromosomal alterations. The aim of this study was to investigate the numerical aberrations of chromosome 20 in breast cancer. The observed chromosome-specific numerical abnormalities were evaluated along with the established clinicopathological parameters, the immunohistochemical expression of ER, PR, p53, c-erbB-2, Ki-67 and patients' survival. Nonisotopic in situ hybridization was applied to interphase cell nuclei on paraffin embedded tissue sections. Polysomy of chromosome 20 was the prevalent alteration in 45 of 50 (90%), monosomy in 2 of 50 (4%) and disomy in 3 of 50 (6%) cases. Invasive ductal carcinomas displayed a higher percentage of polysomy than lobular ones. A statistical significant association was demonstrated between Ki-67 immunohistochemical expression and polysomy of chromosome 20. Disomy was inversely correlated with Ki-67, while monosomy was suggestively associated with PR positive expression. Among the patients, those with the highest levels of polysomy showed the worst survival. In conclusion, the gain of chromosome 20 is the prevalent aberration in patients with breast carcinomas and may be useful prognostic marker in breast cancer. 相似文献
13.
Lamszus K Makrigeorgi-Butera M Laas R Westphal M Stavrou D 《Brain pathology (Zurich, Switzerland)》2003,13(1):115-117
The September 2002 COM. A 24-year-old female presented with a history of 3 generalized seizures, the first of which had occurred 6 months before admission. Her neurological examination was normal, but upon admission her MRI showed a small cystic lesion in the left parieto-occipital region. The lesion was hyper-intense on T-2 weighted images and did not show contrast enhancment. At surgery, the tumor was found to be deep to the cortex and was a cyst with amber fluid surrounded by gliotic brain. Microscopically, the tumor was well-demarcated from the surrounding tissues, which showed reactive changes, including Rosenthal fibers. The tumor was composed of GFAP-positive glial cells, which were arranged in a pseudopapillary fashion around blood vessels. In between, the tumor cells were positive for neuronal markers. The diagnosis was papillary glioneuronal tumor (PGNT), a relatively recently described lesion that may be a variant of ganglioglioma. The current literature on PGNTs is reviewed. 相似文献
14.
15.
Prediction of AVM obliteration after stereotactic radiotherapy using radiobiological modelling 总被引:1,自引:0,他引:1
Mavroidis P Theodorou K Lefkopoulos D Nataf F Schlienger M Karlsson B Lax I Kappas C Lind BK Brahme A 《Physics in medicine and biology》2002,47(14):2471-2494
This study was carried out in order to derive the radiobiological parameters of the dose-response relation for the obliteration of arteriovenous malformation (AVM) following single fraction stereotactic radiotherapy. Furthermore, the accuracy by which the linear Poisson model predicts the probability of obliteration and how the haemorrhage history, location and volume of the AVM influence its radiosensitivity are investigated. The study patient material consists of 85 patients who received radiation for AVM therapy. Radiation-induced AVM obliterations were assessed on the basis of post-irradiation angiographies and other radiological findings. For each patient the dose delivered to the clinical target volume and the clinical treatment outcome were available. These data were used in a maximum likelihood analysis to calculate the best estimates of the parameters of the linear Poisson model. The uncertainties of these parameters were also calculated and their individual influence on the dose-response curve was studied. AVM radiosensitivity was assumed to be the same for all the patients. The radiobiological model used was proved suitable for predicting the treatment outcome pattern of the studied patient material. The radiobiological parameters of the model were calculated for different AVM locations, bleeding histories and AVM sizes. The range of parameter variability had considerable effect on the dose-response curve of AVM. The correlation between the dosimetric data and their corresponding clinical effect could be accurately modelled using the linear Poisson model. The derived response parameters can be introduced into the clinical routine with the calculated accuracy assuming the same methodology in target definition and delineation. The known volume dependence of AVM radiosensitivity was confirmed. Moreover, a trend relating AVM location with its radiosensitivity was observed. 相似文献
16.
Kitty Pavlakis Panteleimon Kountourakis Efstathios Stathopoulos Amanda Psyrri Dimitra Rontogianni Maria Kafousi Maria Derivianaki Nikolaos Xiros Dimitrios Pectasides Theofanis Economopoulos 《Applied immunohistochemistry & molecular morphology》2007,15(4):441-445
This study was sought to evaluate the relationship between Her-2 protein expression, cellular localization, gene amplification, and other clinicopathologic parameters in colorectal carcinomas. Her-2 protein expression and gene amplification were assessed in paraffin sections from 106 primary colorectal adenocarcinoma cases using immunohistochemistry and fluorescence in situ hybridization. Both membranous and cytoplasmic immunostaining was evaluated. The results were correlated with each other and with tumor grade, stage, and overall survival. Membranous and cytoplasmic protein expression was identified in 6 (5.6%) and 13 (12.26%) cases, respectively. Gene amplification was detected in 4 (3.7%) cases. There was a high concordance between membranous protein expression and gene amplification (kappa=0.791). No apparent association with any of the clinicopathologic parameters was identified. Membranous Her-2 protein expression and gene amplification are encountered in a small subset of colorectal carcinomas and are highly concordant events. Cytoplasmic protein expression might be either artifactual or it might represent a cross-reacting protein or a precursor form of the mature protein. 相似文献
17.
Dimitrios I. Athanasiadis Sara Monfared Hamed Asadi Cameron L. Colgate Denny Yu Dimitrios Stefanidis 《Surgery》2021,169(3):496-501
BackgroundWork-related musculoskeletal injuries have been increasingly recognized to affect surgeons. It is unknown whether such injuries also affect surgical trainees. The purpose of this study was to assess the ergonomic risk of surgical trainees as compared with that of experienced surgeons.MethodsErgonomic data were recorded from 9 surgeons and 11 trainees. Biomechanical loads during surgery were assessed using motion tracking sensors and electromyography sensors. Demanding and static positions of the trunk, neck, right/left shoulder, as well as activity from the deltoid and trapezius muscles bilaterally were recorded. In addition, participants reported their perceived discomfort on validated questionnaires.ResultsA total of 87 laparoscopic general surgery cases (48 attendings and 39 trainees) were observed. Both trainees and attendings spent a similarly high percentage of each case in static (>60%) and demanding positions (>5%). Even though residents reported overall more discomfort, all participants shared similar ergonomic risk with the exception of trainees’ trunk being more static (odds ratio: –11.42, P = .006).ConclusionSurgeons are prone to ergonomic risk. Trainees are exposed to similar postural ergonomic risk as surgeons but report more discomfort and, given that musculoskeletal injuries are cumulative over time, the focus should be on interventions to reduce ergonomic risk in the operating room. 相似文献
18.
Pyrgaki Konstantina Argyraki Ariadne Kelepertzis Efstratios Botsou Fotini Megremi Ifigeneia Karavoltsos Sotirios Dassenakis Emmanuel Mpouras Thanasis Dermatas Dimitrios 《Bulletin of environmental contamination and toxicology》2021,106(3):446-452
Bulletin of Environmental Contamination and Toxicology - The holistic approach of Driver-Pressure-State-Impact-Response (DPSIR) methodology was applied to selected Cr(VI) impacted groundwater... 相似文献
19.
The a- and b-wave latencies as a prognostic indicator of neovascularisation in central retinal vein occlusion 总被引:1,自引:0,他引:1
Moschos M Brouzas D Moschou M Theodossiadis G 《Documenta ophthalmologica. Advances in ophthalmology》1999,99(2):123-133
To evaluate the prognostic value of ERG in cases of central retinal vein occlusion (CRVO) regarding the development of neovascularisation
(NV), we studied 20 patients with unilateral CRVO. Half of them were allocated in the perfused group and the other 10 finally
developed NV and were allocated in the non-perfused group. Flash ERG was recorded from all patients. Our findings suggest
that b-wave latency is the most reliable parameter in predicting NV, followed by the a-wave latency. The b/a wave amplitude of ERG ratio does not seem to be suitable for clinical use.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
20.