全文获取类型
收费全文 | 169821篇 |
免费 | 7798篇 |
国内免费 | 492篇 |
专业分类
耳鼻咽喉 | 2490篇 |
儿科学 | 5089篇 |
妇产科学 | 3850篇 |
基础医学 | 22991篇 |
口腔科学 | 5188篇 |
临床医学 | 10973篇 |
内科学 | 41764篇 |
皮肤病学 | 5114篇 |
神经病学 | 13951篇 |
特种医学 | 4615篇 |
外国民族医学 | 7篇 |
外科学 | 20869篇 |
综合类 | 930篇 |
一般理论 | 47篇 |
预防医学 | 16625篇 |
眼科学 | 3533篇 |
药学 | 11745篇 |
中国医学 | 748篇 |
肿瘤学 | 7582篇 |
出版年
2023年 | 973篇 |
2022年 | 1105篇 |
2021年 | 3870篇 |
2020年 | 1957篇 |
2019年 | 3823篇 |
2018年 | 7280篇 |
2017年 | 4336篇 |
2016年 | 3538篇 |
2015年 | 3807篇 |
2014年 | 4747篇 |
2013年 | 6947篇 |
2012年 | 11510篇 |
2011年 | 12169篇 |
2010年 | 6384篇 |
2009年 | 4905篇 |
2008年 | 9898篇 |
2007年 | 10467篇 |
2006年 | 9770篇 |
2005年 | 9760篇 |
2004年 | 8829篇 |
2003年 | 8318篇 |
2002年 | 7881篇 |
2001年 | 4929篇 |
2000年 | 5610篇 |
1999年 | 4277篇 |
1998年 | 963篇 |
1997年 | 635篇 |
1996年 | 626篇 |
1995年 | 522篇 |
1994年 | 420篇 |
1993年 | 389篇 |
1992年 | 1775篇 |
1991年 | 1472篇 |
1990年 | 1388篇 |
1989年 | 1154篇 |
1988年 | 978篇 |
1987年 | 979篇 |
1986年 | 928篇 |
1985年 | 806篇 |
1984年 | 594篇 |
1983年 | 456篇 |
1979年 | 495篇 |
1975年 | 395篇 |
1974年 | 444篇 |
1973年 | 487篇 |
1972年 | 426篇 |
1971年 | 441篇 |
1970年 | 392篇 |
1969年 | 379篇 |
1968年 | 378篇 |
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
91.
Luis J García-Flórez Guillermo Gómez-álvarez Ana M Frunza Luis Barneo-Serra Manuel F Fresno-Forcelledo 《World journal of gastrointestinal surgery》2015,7(9):196-202
AIM: To establish the association between lymph node involvement and the response to neoadjuvant therapy in locally advanced rectal cancer.METHODS: Data of 130 patients with mid and low locally advanced rectal adenocarcinoma treated with neoadjuvant chemoradiation followed by radical surgery over a 5-year period were reviewed. Tumor staging was done by endorectal ultrasound and/or magnetic resonance imaging. Tumor response to neoadjuvant therapy was determined by T-downstaging and tumor regression grading (TRG). Pathologic complete response (pCR) is defined as the absence of tumor cells in the surgical specimen (ypT0N0). The varying degrees TRG were classified according to Mandard’s scoring system. The evaluation of the response is based on the comparison between previous clinico-radiological staging and the results of pathological evaluation. χ2 and Spearman’s correlation tests were used for the comparison of variables.RESULTS: Pathologic complete response (pCR, ypT0N0, TRG1) was observed in 19 cases (14.6%), and other 18 (13.8%) had only very few residual malignant cells in the rectal wall (TRG2). T-downstaging was found in 63 (48.5%). Mean lymph node retrieval was 9.4 (range 0-38). In 37 cases (28.5%) more than 12 nodes were identified in the surgical specimen. Preoperative lymph node involvement was seen in 77 patients (59.2%), 71 N1 and 6 N2. Postoperative lymph node involvement was observed in 41 patients (31.5%), 29 N1 and 12 N2, while the remaining 89 were N0 (68.5%). In relation to ypT stage, we found nodal involvement of 9.4% in ypT0-1, 22.2% in ypT2 and 43.7% in ypT3-4. Of the 37 patients considered “responders” to neoadjuvant therapy (TRG1 and 2), there were only 4 N+ (10.8%) and the remainder N0 (89.2%). In the “non responders” group (TRG 3, 4 and 5), 37 cases were N+ (39.8%) and 56 (60.2%) were N0 (P < 0.001).CONCLUSION: Response to neoadjuvant chemoradiation in rectal cancer is associated with lymph node involvement. 相似文献
92.
93.
94.
An important part of fundamental research in catalysis is based on theoretical and modeling foundations which are closely connected with studies of single-crystalline catalyst surfaces. These so-called model catalysts are often prepared in the form of epitaxial thin films, and characterized using advanced material characterization techniques. This concept provides the fundamental understanding and the knowledge base needed to tailor the design of new heterogeneous catalysts with improved catalytic properties. The present contribution is devoted to development of a model catalyst system of CeO2 (ceria) on the Cu(111) substrate. We propose ways to experimentally characterize and control important parameters of the model catalyst—the coverage of the ceria layer, the influence of the Cu substrate, and the density of surface defects on ceria, particularly the density of step edges and the density and the ordering of the oxygen vacancies. The large spectrum of controlled parameters makes ceria on Cu(111) an interesting alternative to a more common model system ceria on Ru(0001) that has served numerous catalysis studies, mainly as a support for metal clusters. 相似文献
95.
Duds Eszter Susa va Pamjav Horolma Szabolcsi Zoltn 《International journal of legal medicine》2020,134(2):487-489
International Journal of Legal Medicine - Gyula Ágner was a Royal Hungarian First Lieutenant (1st Lt.) during the World War II and died at 30 years old due to a mine shrapnel injury... 相似文献
96.
97.
Águeda Prior-Español Yaiza García-Mira Sonia Mínguez Melania Martínez-Morillo Laia Gifre Lourdes Mateo 《Reumatología clinica》2019,15(6):e81-e85
ObjectiveSeptic arthritis is a medical emergency and crystal-induced arthritis is a risk factor for its development. If both occur simultaneously, crystal-induced arthritis may mask the diagnosis of infection and delay antibiotic therapy.MethodRetrospective analysis of patients with coexistence of septic and crystal-induced arthritis. We included only patients with isolation of crystals in synovial fluid analysis and positive culture of synovial fluid and/or blood culture.ResultsA total of 25 patients (17 men and 8 women) with a mean age of 67 years. The most commonly affected joint was the knee. In synovial fluid cytological studies, the most frequently identified crystals were monosodium urate. Risk factors included diabetes and chronic renal failure. The most frequently isolated germs were methicillin-sensitive S. aureus (48%), methicillin-resistant S. aureus (12%) and Mycobacterium tuberculosis (12%). In all, 36% of subjects required surgical drainage (excluding those caused by M. tuberculosis). Clinical outcome was favorable in 56%, although intercurrent complications were usual (40%). Mortality was 8%.ConclusionsCoexistence of septic and crystal-induced arthritis represents a diagnostic challenge and requires a high index of suspicion. Gout was the most prevalent crystal-induced arthritis. S. aureus was the most commonly causative pathogen, with a high rate of methicillin-resistant S. aureus infection. If treated early, the outcome is usually favorable, making synovial fluid microbiological study imperative. 相似文献
98.
99.
G Steinitz M C Martín N Gazit-Yaari M L Quesada J de la Nuez R Casillas U Malik Z B Begin 《Applied radiation and isotopes》2006,64(4):520-524
Multi-day signals, generally with duration of 2-10 days, are a prominent temporal variation type of radon (Rn) in geogas in the unsaturated zone. Rare multi-day Rn signals have been found which are characterized by: (a) a declining limb lasting up to 10 days which conforms to the radioactive decay of Rn, (b) recurs at the same location and (c) is recorded in diverse situations-volcanic and seismogenic. It suggested that a Rn blob is injected at a lower level on a steady upward flow of geogas whereby the rise and final fall of the signal are attributed to the edges of the blob while the central Rn-decay segment records the passing of the decaying blob itself. Rn-decay signals are a small subset of multi-day Rn signals which are considered as highly irregular and unusable for the understanding of geophysical processes. In difference, it is concluded that multi-day Rn signals are probably proxies of subtle geodynamic processes at upper crustal levels and are therefore significant for studying such processes. 相似文献
100.
H. Wessling C. L. Simosono M. Escosa-Bagé P. de las Heras-Echeverría 《Acta neurochirurgica》2006,148(6):673-675
Summary We present a case of blindness and Anton’s syndrome in a psychiatric patient with late diagnosis of a giant frontal meningioma.
The criteria for advanced diagnostic imaging in the psychiatric population are discussed. We conclude that MR or CT scan is
indicated in psychiatric in-patients who fail to improve with standard psychiatric treatment. This strategy should be submitted
to a cost-benefit analysis. 相似文献