全文获取类型
收费全文 | 1192篇 |
免费 | 40篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 35篇 |
儿科学 | 12篇 |
妇产科学 | 18篇 |
基础医学 | 147篇 |
口腔科学 | 12篇 |
临床医学 | 67篇 |
内科学 | 225篇 |
皮肤病学 | 20篇 |
神经病学 | 103篇 |
特种医学 | 26篇 |
外科学 | 152篇 |
综合类 | 18篇 |
预防医学 | 194篇 |
眼科学 | 24篇 |
药学 | 119篇 |
中国医学 | 11篇 |
肿瘤学 | 56篇 |
出版年
2022年 | 14篇 |
2021年 | 21篇 |
2020年 | 12篇 |
2019年 | 14篇 |
2018年 | 24篇 |
2017年 | 8篇 |
2016年 | 13篇 |
2015年 | 26篇 |
2014年 | 40篇 |
2013年 | 40篇 |
2012年 | 69篇 |
2011年 | 65篇 |
2010年 | 35篇 |
2009年 | 38篇 |
2008年 | 76篇 |
2007年 | 93篇 |
2006年 | 81篇 |
2005年 | 62篇 |
2004年 | 89篇 |
2003年 | 82篇 |
2002年 | 68篇 |
2001年 | 9篇 |
2000年 | 11篇 |
1999年 | 15篇 |
1998年 | 8篇 |
1996年 | 6篇 |
1995年 | 6篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1988年 | 5篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 6篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1979年 | 9篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 8篇 |
1974年 | 7篇 |
1973年 | 7篇 |
1972年 | 6篇 |
1969年 | 5篇 |
1968年 | 6篇 |
1966年 | 7篇 |
1942年 | 4篇 |
1938年 | 6篇 |
1929年 | 4篇 |
排序方式: 共有1239条查询结果,搜索用时 15 毫秒
91.
92.
Katalin Kristó János Bajdik István Eros Imre Dékány Zsolt Pallai Klára Pintye-Hódi 《European journal of pharmaceutics and biopharmaceutics》2008,68(3):741-746
The main objective of this study was to evaluate and to increase the processibility of a model protein (human serum albumin (HSA)) for preparation of an intermediate for a solid dosage form. The applicability of the solid forms is easier, and therefore their formulation is a promising method for the application of proteins. The layering of powdered cellulose with HSA solutions of different concentrations in a fluid bed apparatus with the top spray method was applied. The yield of this technique was very good, independently of the concentration of the applied solution. The HSA covered the particles (the HSA layer formed was smooth), but it caused aggregation of the cellulose particles, and spray-dried microparticles also formed. The proportion of optimum-sized particles (200-315 microm) decreased. The largest amount was detected for the samples prepared with liquid containing 15% HSA (about 2 times higher than the second best). Not only the size, but also the shape of the particles was changed. The alteration in this parameter caused a change in the flowability. This was likewise the best for the samples prepared with the liquid containing 15% HSA. The concentration of HSA in the fraction containing smaller particles was higher, because of the abrasion of the particles and the enrichment of the spray-dried HSA. The distribution of HSA in the large particles was uneven. The layering of powder cellulose can be applied to produce an intermediate from HSA for solid dosage forms, but the appropriate concentration of this protein solution must be optimized previously because HSA can act as a binder. The formation of large agglomerates must be eliminated, because the distribution of the active agent in these is very inhomogeneous. The present results indicated that the best value can be achieved with liquid containing between 12.5% (most homogeneous distribution of HSA) and 15% HSA (best flowability). 相似文献
93.
Szabolcs Szakáll Olga Esik Gábor Bajzik Imre Repa Gabriella Dabasi István Sinkovics Péter Agoston Lajos Trón 《Journal of nuclear medicine》2002,43(1):66-71
Postsurgically elevated or increasing serum calcitonin levels strongly suggest the presence of residual or recurrent medullary thyroid carcinoma (MTC). Several imaging modalities (sonography, MRI, CT, scintigraphy with different types of radiolabeled ligands, etc.) are routinely used in an attempt to localize tumorous tissue, but such efforts often fail. In the search for a more reliable method, 18F-FDG PET was applied to detect tumor tissue of residual or recurrent MTC. METHODS: Forty patients with a postoperatively elevated plasma calcitonin level were included. These patients underwent routine diagnostic imaging procedures (CT, MRI, and 131I-metaiodobenzylguanidine [MIBG] whole-body planar scintigraphy or SPECT) and 18F-FDG PET examinations. Two independent experts visually analyzed the images provided by each method to detect pathologic lesions. Lymph nodes of > or = 1 cm in short diameter that were detected by radiologic methods were considered to be pathologic. 18F-FDG accumulation with a sharp contour reported by both independent observers was similarly regarded as pathologic. RESULTS: PET detected 270 foci with a high tracer accumulation, whereas only 116 lesions were detected by MRI and 141 by CT. The numbers of such foci determined by PET, MRI, and CT were 98, 34, and 34, respectively, in the neck; 25, 5, and 6, respectively, in the supraclavicular regions; and 117, 35, and 39, respectively, in the mediastinum. 131I-MIBG scintigraphy findings were positive for only 3 patients. CONCLUSION: For MTC patients with a postoperatively elevated plasma tumor marker level, PET was more sensitive and superior in localizing tumorous lymph node involvement than were the other imaging modalities, especially in the cervical, supraclavicular, and mediastinal lymphatic regions. 相似文献
94.
Peter Diószeghy Sándor Imre Ferenc Mechler 《European archives of psychiatry and clinical neuroscience》1989,238(3):175-177
Summary Lipid peroxidation (LP) and superoxide dismutase (SOD) activity were determined in erythrocytes and skeletal muscle obtained from patients with limb-girdle and facioscapulohumeral muscular dystrophies, neurogenic atrophies and from age-matched control subjects. Neither lipid peroxidation nor SOD activity in erythrocytes of patients differed from control values. SOD activity and LP in muscle specimens were also normal in types of neurogenic atrophy. Lipid peroxidation in the muscle from patients with adult types of muscular dystrophy had a tendency to be increased. The values were widely scattered, the highest being obtained in the older patients with long duration of disease. 相似文献
95.
96.
97.
Objective
Within the context of the Third i2b2 Workshop on Natural Language Processing Challenges for Clinical Records, the authors (also referred to as ‘the i2b2 medication challenge team’ or ‘the i2b2 team’ for short) organized a community annotation experiment.Design
For this experiment, the authors released annotation guidelines and a small set of annotated discharge summaries. They asked the participants of the Third i2b2 Workshop to annotate 10 discharge summaries per person; each discharge summary was annotated by two annotators from two different teams, and a third annotator from a third team resolved disagreements.Measurements
In order to evaluate the reliability of the annotations thus produced, the authors measured community inter-annotator agreement and compared it with the inter-annotator agreement of expert annotators when both the community and the expert annotators generated ground truth based on pooled system outputs. For this purpose, the pool consisted of the three most densely populated automatic annotations of each record. The authors also compared the community inter-annotator agreement with expert inter-annotator agreement when the experts annotated raw records without using the pool. Finally, they measured the quality of the community ground truth by comparing it with the expert ground truth.Results and conclusions
The authors found that the community annotators achieved comparable inter-annotator agreement to expert annotators, regardless of whether the experts annotated from the pool. Furthermore, the ground truth generated by the community obtained F-measures above 0.90 against the ground truth of the experts, indicating the value of the community as a source of high-quality ground truth even on intricate and domain-specific annotation tasks. 相似文献98.
Tibor Kovács Marianna Farsang Edina Vitaszil Péter Barsi Tamás Györke Imre Szirmai Anita Kamondi 《Journal of neural transmission (Vienna, Austria : 1996)》2009,116(12):1631-1634
Levetiracetam (LEV) has been shown to suppress myoclonus of various origins. Corticobasal degeneration (CBD), a progressive
neurodegenerative disorder with Parkinsonian syndrome, is frequently accompanied by myoclonus. We investigated the effect
of LEV on myoclonus in two CBD patients. LEV remarkably decreased the myoclonic activity in both patients already at 1,500 mg/day
dose. This is the first report on LEV alleviating myoclonus in CBD. Our data indicate that it might be worthwhile to assess
this effect in an appropriately designed study. 相似文献
99.
Background The time of onset of myocardial infarction shows seasonal and daily variation. We aimed to investigate whether the number of hours with daylight has an effect on the seasonal variation of heart attack, and whether the time of sunrise has an effect on the diurnal rhythm of myocardial infarction. Methods We carried out a retrospective database study covering all patients admitted to any acute care hospital with the diagnosis of myocardial infarction in Hungary between January 2004 and December 2005 (n=32 329). Data were collected from the National Health Insurance Fund Administration (OEP) according to the International Classification of Diseases (ICD 121, 122) and National Meteorology Service (OMSZ). In case of patients who occurred in the database several times the events have been considered as a separate case. Results With consideration to seasonal variation, the peak period of heart attack was found in the spring, with the lowest number of events in the summer. The number of hours with daylight showed a weak negative correlation with the occurrence of myocardial infarction (r=-0.108, P 〈0.05). With respect to diurnal variation, the peak period of daily events was between 6-12 in the morning (35.57%). We have found a positive correlation between the time of sunrise and sunset and the occurrence of myocardial infarction (P 〈0.01). Conclusion Based on our findings, the number of hours with daylight and the time of sunrise may be connected with the chances of having heart attack; however other factors, such as high blood pressure, diabetes or smoking may also have an influence. 相似文献