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41.
快速检测产单核李斯特菌免疫胶体金层析法的研究 总被引:4,自引:0,他引:4
目的:为产单核李斯特菌提供了一个方便快捷切实有效的检测技术。方法:采用胶体金标记产单核李斯特菌抗体制备免疫层析检测试剂,通过免疫层析作用对产单核李斯特菌进行检测。结果:通过选用柠檬酸钠改良法制备胶体金,测定其最适结合蛋白浓度为28μg/ml,构建起免疫层析检测试剂和检测方法,检测了冷冻猪肉、牛奶、冰激凌以及不同稀释度的产单核李斯特菌标准样品,灵敏度达87.5%,具有良好的重现性。结论:免疫胶体金层析法用于快速检测产单核李斯特菌是可行的。 相似文献
42.
Johan Sandell 《Journal of labelled compounds & radiopharmaceuticals》2012,55(14):499-500
[14C]Formaldehyde was synthesized by reducing 14CO2 at ambient temperature with Schwartz's reagent. The [14C]formaldehyde was then used in the radiosynthesis of high specific activity (2.1 GBq/mmol) [14C]hydrochlorothiazide via cyclization of 4‐amino‐5‐chloro‐1,3‐benzenedisulfonamide. 相似文献
43.
David J. Schenk Dave Hesk Rosemary Marques Roy Helmy Patty Cheung 《Journal of labelled compounds & radiopharmaceuticals》2012,55(12):447-449
The specific activities for a series of S‐35 tracers were found to vary from the decay‐corrected specific activity of the labeled reagent. If not known before the stock solution preparation and binding assay, this variation would have resulted in performing the assay at approximately two to three times over the targeted concentration, thereby leading to considerable error in the calculated binding and related conclusions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
44.
《Statistics In Biopharmaceutical Research》2013,5(3):268-278
In this article, we describe an adjusted method to facilitate a noninferiority trial using a three-arm robust design. Because local optimal designs derived by Hasler et al. require knowledge about the ratios of the population variances and are not necessarily robust with respect to possible misspecifications, we adopt a maximin approach. This method requires only the specification of an interval for the variance ratios and yields robust and efficient designs. We demonstrate that a maximin optimal design depends only on the boundary points specified for the variance ratios’ intervals and we obtain numerical and analytical solutions which are demonstrated in several examples. The derived designs are robust and very efficient for statistical analysis in noninferiority three-arm trials. 相似文献
45.
《Vaccine》2014,32(27):3460-3467
We have previously shown that the combination of MIDGE-Th1 DNA vectors with the cationic lipid SAINT-18 increases the immune response to the encoded antigen in mice. Here, we report on experiments to further optimize and characterize this approach. We evaluated different formulations of MIDGE-Th1 vectors with SAINT-18 by assessing their influence on the transfection efficiency in cell culture and on the immune response in mice. We found that high amounts of SAINT-18 in formulations with a w/w ratio MIDGE Th1/SAINT-18 of 1:4.8 are beneficial for cell transfection in vitro. In contrast, the formulation of HBsAg-encoding MIDGE-Th1 DNA vectors with the lowest amount of SAINT-18 (w/w ratio MIDGE Th1/SAINT-18 of 1:0.5) resulted in the highest serum IgG1 and IgG2a levels after intradermal immunization of mice. Consequently, latter formulation was selected for a comparative biodistribution study in rats. Following intradermal administration of both naked and formulated MIDGE-Th1 DNA, the vectors localized primarily at the site of injection. Vector DNA levels decreased substantially over the two months duration of the study. When administered in combination with SAINT-18, the vectors were found in significantly higher amounts in draining lymph nodes in comparison to administration of naked MIDGE-Th1 DNA. We propose that the high immune responses induced by MIDGE-Th1/SAINT-18 lipoplexes are mediated by enhanced transfection of cells in vivo, resulting in stronger antigen expression and presentation. Importantly, the combination of MIDGE-Th1 vectors with SAINT-18 was well tolerated in mice and rats and is expected to be safe in human clinical applications. 相似文献
46.
47.
Catherine M. Champagne Hongmei Han Sudip Bajpeyi Jennifer Rood William D. Johnson Carol J. Lammi-Keefe Jean-Pierre Flatt George A. Bray 《Journal of the Academy of Nutrition and Dietetics》2013,113(11):1532-1538
Because day-to-day food intake varies, we tested the hypothesis that ad libitum food intake and energy expenditure show corrective responses over periods of 1 to 10 days in healthy young women. Food intake and accelerometry measurements were collected daily for 17 days in 15 young women. Total daily energy expenditure (TDEE) using doubly labeled water was also measured. The daily deviations in macronutrient and energy intake and energy expenditure from the average values were compared with the deviations observed over succeeding intervals to estimate the corrective responses. The intraindividual coefficients of variation for energy intake averaged ±25%, ranging from 16% to 34%. TDEE had a coefficient of variation of 8.3%, and accelerometry had a coefficient of variation of 8.4% (range=4.6% to 16.4%). Energy expenditure by accelerometry (2,087±191 kcal/day) was not significantly different from TDEE (2,128±177 kcal/day), but reported daily energy intake was 20.4% lower (1,693±276 kcal/day). There were significant corrective responses in energy from fat and total energy intake. This occurred from Days 3 to 6, with a peak at Day 5 that disappeared when data were randomized within each subject. Human beings show corrective responses to deviations from average energy and macronutrient intakes with a lag time of 3 to 6 days, but not 1 to 2 days. These corrective responses are likely to play a role in bringing about weight stability. 相似文献
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49.
Vabitha Shetty MDS Pooja B.L. Amitha M. Hegde BSc BDS MDS 《Special care in dentistry》2014,34(1):34-40
The study sample consisted of 100 children with visual impairment aged 6–14 years. 6‐n‐propylthiouracil (PROP) sensitivity test was carried out. The Caries experience was recorded, estimation of Streptococcus mutans done and their taste likes and dislikes assessed through a food preference questionnaire. The Caries experience and S. mutans levels were highest in the non‐tasters, comparatively low in medium tasters and the least in the supertasters. Dietary preferences indicated tasters were sweet dislikers and non‐tasters, sweet likers. PROP test can be a useful tool in determining genetic taste sensitivity levels amongst the visually impaired children and thus used as a screening tool in those children who are at a high risk of developing dental caries. 相似文献
50.
Suqin Zhu Mingyong Zeng Wei Guo Guangxin Feng 《journal of environmental science and health part c-environmental carcinogenesis & ecotoxicology reviews》2019,37(2):55-66
Gold nanoparticles (AuNPs) have been previously shown to induce gut dysbiosis during colitis in mice, but the underlying mechanism is not clear yet. Here, we evaluated the effects of AuNPs (5?nm diameter, coated with tannic acid, polyvinylpyrrolidone or citrate) on H2O2 accumulation and pathogen antagonization by an intestinal strain of Lactobacillus gasseri under aerobic cultural conditions. AuNPs (0.65?μg/mL) reduced over 50% of H2O2 accumulation by L. gasseri, and significantly inhibited the antagonistic action of L. gasseri on growth of four foodborne enteric pathogens, i.e. Salmonella enterica serovar Typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus in associative cultures. 相似文献