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71.
《Expert review of anticancer therapy》2013,13(11):1559-1568
Melanoma is one of the few tumors that have increased in incidence over the last few decades. Strategies devoted solely to protecting against ultraviolet radiation have, at best, had a modest impact on the development of melanoma. Chemoprevention is an under-explored approach that could significantly decrease the morbidity and mortality from this deadly cancer. However, the scientific and logistical challenges of performing clinical studies in chemoprevention require innovative approaches to prove the effectiveness of putative preventive agents. There are several pharmacological and nutriceutical agents that are mechanistically linked to events in melanoma carcinogenesis that are candidates for advanced human studies. We will review the data for several promising agents, including statins, curcumin, resveratrol, silymarin and green tea, and discuss some importance issues and concepts that should be considered in any melanoma chemoprevention strategy. 相似文献
72.
目的分析北京、成都、上海、广州居民的夏季一天不同时间段的饮水行为。方法采用多阶段随机抽样方法从四城市抽取18~60岁成年人1483名,使用连续7天的饮水记录表,由调查对象利用定量用具详细记录每天8个时间段内每次饮水的种类及饮水量。结果调查对象早、中、晚餐后的饮水率(97%~99%)及饮水量(290~471ml)较其他5个时间段高(饮水率:49%~88%;饮水量:54~166ml,F=972.55,P<0.01);白水、茶水、饮料的饮水人数与饮水量的分布情况同总水趋势一致。调查对象上午(719ml/d)的饮水量最高,其次是下午(539ml/d),晚上(417ml/d)的最低(F=265.49,P<0.01)。白水和饮料的饮用量均是上午最高;茶水上午和下午的接近,同时高于晚上(t=-52.13,P<0.01)。非就餐时(1436ml/d)的饮水量高于就餐时(240ml/d)的饮水量。就餐时饮料的饮用量最高;非就餐时白水的饮用量最高(P<0.05)。结论我国四城市居民在上午、下午、晚上均以饮用白水为主;就餐时以饮用饮料为主,非就餐时以白水为主。 相似文献
73.
There are many emerging adsorbents, with relatively high adsorption capacities, that can be used during the extraction of pesticides from complex matrices. Poly(ionic liquids) are among these emerging adsorbents. The applications of poly(ionic liquids) as adsorbents during pesticide pre-concentration are explored in this paper. Some researchers have taken advantage of the adhesive nature of polydopamine and used it to synthesise adsorbents with relatively high adsorption capacities. The use of polydopamine-based sorbents during pesticide pre-concentration is also reviewed in this paper. Deep eutectic solvents, on the other hand, can be used to synthesise adsorbents to extract pesticides in complex matrices. This is usually done either by immobilising it on a solid support or by polymerisation. Applications of deep eutectic solvent-based adsorbents during pesticide extraction are discussed in detail in this review. In addition, this review has explored the challenges associated with the use of these emerging adsorbents during the extraction of pesticides as well as the future prospects. 相似文献
74.
Calcineurin and mTOR inhibitors are commonly used immunosuppressive agents with narrow therapeutic range. As the drugs are mainly metabolized by the P450 cytochrome system, the interaction between food and herbs are also commonly seen and affect the drug levels. We present a case of a kidney transplant recipient with toxic therapeutic levels of cyclosporine A and sirolimus due to interaction between the immunosuppressive agents and Chinese herbal tea. Ingredients within the herbal tea were reported to have inhibitory effect on cytochrome CYP3A4 in-vitro studies. Transplant recipients should be alert that there may be potent interaction between the immunosuppressive drugs and herbs resulting in adverse effect on allograft function. 相似文献
75.
《Journal of nutrition education and behavior》2014,46(5):324-333
ObjectiveTo develop and validate an instrument to assess environmentally conscious eating (Green Eating [GE]) behavior (BEH) and GE Transtheoretical Model constructs including Stage of Change (SOC), Decisional Balance (DB), and Self-efficacy (SE).DesignCross-sectional instrument development survey.Setting/ParticipantsConvenience sample (n = 954) of 18- to 24-year-old college students from a northeastern university.AnalysisThe sample was randomly split: (N1) and (N2). N1 was used for exploratory factor analyses using principal components analyses; N2 was used for confirmatory analyses (structural modeling) and reliability analyses (coefficient α). The full sample was used for measurement invariance (multi-group confirmatory analyses) and convergent validity (BEH) and known group validation (DB and SE) by SOC using analysis of variance.ResultsReliable (α > .7), psychometrically sound, and stable measures included 2 correlated 5-item DB subscales (Pros and Cons), 2 correlated SE subscales (school [5 items] and home [3 items]), and a single 6-item BEH scale. Most students (66%) were in Precontemplation and Contemplation SOC. Behavior, DB, and SE scales differed significantly by SOC (P < .001) with moderate to large effect sizes, as predicted by the Transtheoretical Model, which supported the validity of these measures.Conclusions and ImplicationsSuccessful development and preliminary validation of this 25-item GE instrument provides a basis for assessment as well as development of tailored interventions for college students. 相似文献
76.
77.
Green tea prevents vascular disturbs and attenuates periodontal breakdown in long‐term hyperglycaemia in T1D rats 下载免费PDF全文
78.
Gluconic acid is non-toxic, non-volatile, non-corrosive, and easily biodegradable chemical, which can be produced from biomass using several methods: oxidation by molecular oxygen using heterogeneous catalysis, enzymatic oxidation, and microbial fermentation. Being highly soluble in water, gluconic acid can form concentrated aqueous solutions, and its 50% aqueous solution has found application as a catalytic medium for organic synthesis. For some reactions, gluconic acid aqueous solutions (GAAS) outperform conventional and green solvents when used as media for organic synthesis. GAAS was found to be particularly efficient in the Knoevenagel condensation, the Michael addition, and multicomponent reactions based on them. These and other chemical transformations utilizing GAAS as a medium are discussed in this review. We also compare the effectiveness of GAAS as a new green catalytic medium and the performance of other solvents and catalysts. 相似文献
79.
L. X. Peng L. Zou J. B. Wang J. L. Zhao D. B. Xiang G. Zhao 《Indian journal of pharmaceutical sciences》2015,77(6):661-667
The rutin, quercetin concentrations, antioxidant activity, and aroma compounds in different commercial tartary buckwheat tea were analyzed in our study. Results revealed that the materials and the processing protocol affected the chemical composition and activity of tartary buckwheat tea. Rutin and quercetin concentrations, antioxidant activity were significantly different in various kinds of tartary buckwheat tea, where the whole bran tea and the whole plant tea had the lower rutin, but higher quercetin concentrations and higher antioxidant activity. The whole embryo tea had the converse results. There was strong correlation between quercetin concentration and antioxidant activity (r>0.98, P<0.05). Meanwhile, Twenty eight different aroma compounds in tartary buckwheat tea were identified by gas chromatography-mass spectrometry. Those compounds were mainly composed of pyrazine, aldehydes, fatty acids and ketones. The main type of aroma compounds in different tartary buckwheat tea were similar, but their relative contents were different. The implications to the quality control of buckwheat tea were extensively discussed. 相似文献
80.
目的观察中药内服外用兼针灸治疗婴幼儿湿疹的疗效。方法将82例婴幼儿湿疹患儿分为观察组和对照组,观察组43例,对照组39例,观察组采用内服加减消风导赤汤,外用肤乐霜,加针灸治疗;对照组采用西医抗组胺类药、抗生素、皮质类固醇激素等全身治疗和局部治疗。结果观察组有效率为97.7%,治愈率为72.1%;对照组有效率为79.5%,治愈率为59.0%。结论中药内服外用兼针灸治疗婴幼儿湿疹疗效显著,明显优于单纯西医治疗。中医治疗婴幼儿湿疹具有安全可靠、毒副作用小、疗效持久、复发率低的特点。 相似文献