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排序方式: 共有454条查询结果,搜索用时 31 毫秒
21.
This study evaluated the haematology and clinical chemistry profile of rats given drinking water contaminated with varied
low percentages of used engine oil (UEO) for a period of 21 days. Fifty female albino rats of 6–7 weeks of age were used for
the study. They were divided into five groups (A–E) and given water contaminated with 5%, 1%, 0.1%, 0.01% and 0% vol/vol.
of UEO respectively as the only source of drinking water for 21 days. The group E given uncontaminated water (0% contamination)
served as the control. The haematological parameters and clinical chemistry profile of the rats was comprehensively evaluated
after the 21 days of administration of the group-specific waters. Results showed that contamination of water with up to 5%
UEO led to no significant effects (p > 0.05) on all the haematological indices and on the levels of serum alanine amino transferase, aspartate amino transferase,
albumin, creatinine and calcium, blood urea nitrogen and fasting blood glucose level, feed consumption and body weight. However,
the rat group given water contaminated with 5% UEO had a significantly increased serum alkaline phosphatase (AP) (p < 0.01), total bilirubin (p < 0.05) and cholesterol (p < 0.01), and a significantly decreased serum total protein and globulin (p < 0.01), and water consumption (p < 0.05). The rat group given water contaminated with 1% UEO had a significantly increased serum AP (p < 0.01), total bilirubin (p < 0.05) and cholesterol (p < 0.01), and a significantly decreased water consumption (p < 0.05), while the rat group given water contaminated with 0.1% UEO had a significantly elevated (p < 0.01) serum AP. It was concluded that sub-acute contamination of drinking water of rats with up to 5% UEO led to hepato-biliary
disorders and adverse effects on hepatic secretion and excretion, including diminution of serum protein and globulin levels
and elevation of serum cholesterol levels, but did not lead to any significant effects on haematology, hepatocellular integrity,
kidney/renal function, pancreatic function and body weight. 相似文献
22.
利用网络获取医学信息探讨 总被引:1,自引:0,他引:1
结合首都医科大学附属北京佑安医院实践,介绍如何利用网络获取医学信息以及信息获取过程中存在的问题,在此基础上提出进一步开发利用网络信息资源的途径,包括重视人才培养、寻找交流平台、增强安全防范意识等方面。 相似文献
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25.
目的探讨汽油机尾气致肺脏慢性损伤的形态学改变。方法大鼠40只,随即分为8组,即对照组、1d、3d、1周、2周、4周、8周、12周,每组5只,将汽油机尾气通入装有实验大鼠的自制染毒容器中染毒,每天染毒2h,于1d、3d、1周、2周、4周、8周、12周分别处死实验大鼠,对肺组织进行HE染色、masson染色,显微镜下对肺组织进行观察。结果前2周以炎症反应为主,4周后可见肺组织开始出现成纤维细胞增生,随时间延长,纤维组织增生也越来越明显,但仍有慢性炎症反应。结论汽油机尾气长期染毒可致大鼠肺脏损伤,以纤维化和慢性炎症为主。 相似文献
26.
Literature reviews are an essential step in the research process and are included in all empirical and review articles. Electronic databases are commonly used to gather this literature. However, several factors can affect the extent to which relevant articles are retrieved, influencing future research and conclusions drawn. The current project examined articles obtained by comparable search strategies in two electronic archives using an exemplar search to illustrate factors that authors should consider when designing their own search strategies. Specifically, literature searches were conducted in PsycINFO and PubMed targeting review articles on two exemplar disorders (bipolar disorder and attention deficit/hyperactivity disorder) and issues of classification and/or differential diagnosis. Articles were coded for relevance and characteristics of article content. The two search engines yielded significantly different proportions of relevant articles overall and by disorder. Keywords differed across search engines for the relevant articles identified. Based on these results, it is recommended that when gathering literature for review papers, multiple search engines should be used, and search syntax and strategies be tailored to the unique capabilities of particular engines. For meta-analyses and systematic reviews, authors may consider reporting the extent to which different archives or sources yielded relevant articles for their particular review. 相似文献
27.
Carolina Panis Luciana Pizzatti Ana Cristina Herrera Rubens Cecchini Eliana Abdelhay 《Cancer letters》2013
This study evaluated the plasmatic proteomic profile of breast cancer patients in the early (ED) and advanced (AD) stages, employing high-throughput proteomics. We identified 92 differentially expressed proteins in ED and 73 proteins in AD patients. Gelsolin, lumican, clusterin, SALL4 and PMS2, as well hTERT, TNF-α and GRHL3 were chosen for further investigation. ED presented augmented expression of GRHL3 and reduced circulating TNF-α with high expression of GRHL3 in tumors. AD displayed high TNF-α and a significant expression of PMS2 in tumors. These findings suggest processes enrolling stem cell division in ED, with TNF-α signaling and DNA mismatch repair in the advanced stage. 相似文献
28.
《Toxicology in vitro》2010,24(4):1119-1125
Gasoline engine exhaust has been considered as a major source of air pollution in China. Due to lower cyto- and geno-toxicity effects of methanol engine exhaust, methanol is regarded as a potential substitute for gasoline. We have previously compared cyto- and geno-toxicities of gasoline engine exhaust with that of methanol engine exhaust in A549 cells (Zhang et al., 2007).To characterize the immunotoxic effects for gasoline and methanol engine exhausts in immune cell, in this study, we further compared effects of gasoline and methanol engine exhausts on immune function in RAW264.7 cell and rabbit alveolar macrophages. Results showed that both gasoline and methanol engine exhaust could evidently inhibit RAW264.7 cell proliferation, promote RAW264.7 cell apoptosis, decrease E-rosette formation rate and inhibit anti-tumor effects of alveolar macrophages, at the same time, these effects of gasoline engine exhaust were far stronger than those of methanol engine exhaust. In addition, gasoline engine exhaust could significantly inhibit activities of ADCC of alveolar macrophages, but methanol engine exhaust could not. These results suggested that both gasoline and methanol engine exhausts might be immunotoxic atmospheric pollutants, but some effects of gasoline engine exhaust on immunotoxicities may be far stronger than that of methanol engine exhaust. 相似文献
29.
How to perform a comprehensive search for FDG-PET literature 总被引:1,自引:0,他引:1
G. Sophie Mijnhout Lotty Hooft Maurits W. van Tulder Walter L.J.M. Devillé Gerrit J.J. Teule Otto S. Hoekstra 《European journal of nuclear medicine and molecular imaging》2000,27(1):91-97
In this study, a comprehensive, unbiassed search strategy for identifying literature on fluorine-18 fluorodeoxyglucose positron
emission tomography (FDG-PET) in Medline, Embase and Current Contents was developed, with specific search strategies for each
database, using MeSH terms as well as free text words for PET and FDG. To examine which text words apply to FDG, we evaluated
the ways of spelling FDG in a random sample of FDG-PET articles (n=100). These words were used as free text words in the two databases and overlap was determined. PET publications were identified
using the text words ”positron emission tomography” and ”pet$” combined with the respective MeSH terms for each database.
To compare the yield of the combined FDG-PET strategy in each database, the retrieved citations were downloaded to Pro-Cite
4.0. Finally, we added search terms for lung cancer, breast cancer, melanoma, head and neck cancer and lymphoma to our strategy
and to a short strategy (consisting of the text words ”positron emission tomography” and ”fdg”). In order to measure the yield
and precision (positive predictive value, PPV) of our search strategy and compare it with the short one, we screened the title
and abstract of the retrieved citations. Reviewing a random sample of the FDG-PET literature yielded 56 different ways of
spelling FDG. We confined the list to 11 text words, without missing articles. Of the publications retrieved by these text
words, only 4% were indexed by the MeSH term ”Fludeoxyglucose F18” in Medline and 29% by the MeSH-term ”Fluorodeoxyglucose
F18” in Embase. Only 51% of PET articles were indexed by the MeSH term ”Tomography, emission-computed” in Medline and 40%
by the MeSH term ”Positron emission tomography” in Embase. The combined search strategy for identifying studies on FDG and
PET resulted in 2865 publications in Medline and 2646 in Embase. Medline identified 1662 publications not found by Embase;
Embase identified 1422 publications not found by Medline. Compared with the short strategy, our search strategy yielded on
average 52% more publications (94%, 41% and 20% more in Medline, Embase and Current Contents, respectively). The PPV of our
strategy (percent of publications that were really on PET, FDG and the specified subject) was 70%, compared with 76% using
the short strategy. Regardless of the strategy used, Embase yielded more publications and was also slightly more specific
than Medline. With the recommended strategy, FDG-PET publications can be identified more efficiently. We have shown the importance
of searching more than one database and emphasize the use of both MeSH terms and text words in a search strategy. Standardization
of the spelling of FDG and indexing of articles on FDG would substantially simplify searching.
Received 5 July and in revised form 25 September 1999 相似文献
30.
Resin transfer molding of an inorganic polymer binder was successfully demonstrated in the preparation of ceramic fiber reinforced engine exhaust valves. Unfortunately, in the preliminary processing trials, the resulting composite valves were too brittle for in-engine evaluation. To address this limited toughness, the effectiveness of a modified fiber-matrix interface is investigated through the use of carbon as a model material fiber coating. After sequential heat treatments composites molded from uncoated and carbon-coated fibers are compared using room temperature 3-point bend testing. Carbon-coated Nextel fiber reinforced geopolymer composites demonstrated a 50% improvement in strength, versus that of the uncoated fiber reinforced composites, after the 250 °C postcure. 相似文献