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31.
茶树油的提取工艺优化试验研究   总被引:1,自引:0,他引:1  
郑恒  杜光  宗凯  贡雪芃  叶青 《中国药师》2004,7(3):166-167
目的:以茶树油提取率为考察指标,研究茶树油的提取工艺.方法:采用正交试验进行优选,气相色谱法测定4-羟基萜烯含量.结果:影响茶树油提取率的主要因素是提取时间,对茶树油的提取有显著影响;其次是加水量,对茶树油的提取有较大影响;浸泡时间的影响最小.各因素对4-羟基萜烯含量无影响.结论:最佳的提取工艺为浸泡时间2 h,提取时间6 h,加水800 ml.  相似文献   
32.
目的:研究茶属植物及茶多酚类和嘌呤碱类成分对抗原刺激RBL-2H3细胞脱颗粒及肿瘤坏死因子α(TNF-α)和白细胞介素4(IL-4)释放的抑制作用。方法:测定β-hexosaminidase的释放以评价脱颗粒反应的指标,酶联免疫吸附法测定TNF-α和IL-4的释放,评价茶中主要成分的抗过敏活性。结果:茶属植物均有抑制RBL-2H3细胞脱颗粒作用,其中花类表现出较叶类更强的抗过敏活性;EGCG对抗原刺激的RBL-2H3细胞即刻相(IC50:234μmol·L-1)和延缓相反应(IL4,IC50:158μmol·L-1),及钙离子载体A23187诱导的脱颗粒反应均有抑制作用(IC50:126μmol·L-1)。结论:茶属植物和EGCG具有明显的抗过敏作用。  相似文献   
33.
消痹灵袋泡剂治疗强直性脊柱炎的临床研究   总被引:5,自引:0,他引:5  
周翠英  张鹏 《中成药》1999,21(6):299-302
以消痹灵袋泡剂为治疗组,以消痹灵水煎剂,湿热痹冲剂分别为对照甲,乙组,共治疗强直性脊柱炎80例。治疗组临床治愈率为21.43%,总有效率为95%。与对照乙组相比具有显著差异,与对照甲组相比无显著差异。说明消痹灵袋光剂疗效明显优于湿热痹冲剂,与消痹灵水煎剂疗效相当。  相似文献   
34.
Green tea and bone metabolism   总被引:1,自引:0,他引:1  
Osteoporosis is a major health problem in both elderly women and men. Epidemiological evidence has shown an association between tea consumption and the prevention of age-related bone loss in elderly women and men. Ingestion of green tea and green tea bioactive compounds may be beneficial in mitigating bone loss of this population and decreasing their risk of osteoporotic fractures. This review describes the effect of green tea or its bioactive components on bone health, with an emphasis on (i) the prevalence and etiology of osteoporosis; (ii) the role of oxidative stress and antioxidants in osteoporosis; (iii) green tea composition and bioavailability; (iv) the effects of green tea and its active components on osteogenesis, osteoblastogenesis, and osteoclastogenesis from human epidemiological, animal, as well as cell culture studies; (v) possible mechanisms explaining the osteoprotective effects of green tea bioactive compounds; (vi) other bioactive components in tea that benefit bone health; and (vii) a summary and future direction of green tea and bone health research and the translational aspects. In general, tea and its bioactive components might decrease the risk of fracture by improving bone mineral density and supporting osteoblastic activities while suppressing osteoclastic activities.  相似文献   
35.
目的建立毓麟茶的质量控制方法。方法采用薄层色谱法对毓麟茶中黄芪、蛇床子、五味子、枸杞子进行定性鉴别,采用高效液相色谱法测定君药五味子有效成分五味子醇甲的含量。色谱条件:Welch Materials C18色谱柱(250 mm×4.6 mm,5μm),甲醇-水(70∶30)为流动相,检测波长250 nm。结果薄层色谱鉴别方法简便,专属性强。五味子醇甲0.222~0.2220μg范围内呈良好的线性关系,r=0.9999,平均加样回收率为98.96%,RSD=0.74%。结论所建立的方法可用于该制剂的质量控制。  相似文献   
36.
茶叶中铝的来源及溶解性研究   总被引:6,自引:1,他引:6  
本文采用微波消解法和沸水浸泡法处理茶叶、石墨炉原子吸收光谱法测定16种茶叶中总铝和水溶性铝含量。均值分别为601.6mg/kg和148.3mg/kg。茶叶中水溶性铝占总铝含量的24.7%。对广东省五个茶场的现场采样调查表明茶叶中的铝主要来源于茶树根系对铝的特异吸收。老叶片铝含量远高于嫩叶片是造成茶叶铝含量波动较大的主要原因  相似文献   
37.
毕武  姚霞  何春年  彭勇  肖培根 《中国现代中药》2013,15(11):1012-1018
综述文献资料,对我国别样茶之一的香风茶进行总结和探讨。香风茶为蜡梅科蜡梅属植物山蜡梅Chimonanthus nitens Oliv、柳叶蜡梅C.salicifolius S.Y.Hu和浙江蜡梅C.zhejiangensis M.C.Liu的嫩叶经加工而成,具有祛风解表,理气化痰,醒脾化浊等功效。香风茶在我国民间应用广泛,历史悠久。现代研究表明,其主要化学成分为挥发油、黄酮和生物碱类等,药理活性主要为抗菌抗病毒、降压、降脂减肥、抗氧化和抗肿瘤等作用。香风茶是一种具有广阔开发前景的茶饮,值得继续深入系统研究。  相似文献   
38.

Ethnopharmacological relevance

The volatile essential oil derived from the plant Melaleuca alternifolia, also called tea tree oil (TTO), is largely employed for its antimicrobial properties against several human pathogens. It is used in many topical formulations to treat cutaneous infections.

Aim of the study

Since very few studies have been done on the safety and toxicity of the crude Melaleuca alternifolia essential oil, current investigation evaluates the possible genotoxic effects of TTO in human lymphocyte cultures.

Material and methods

The composition of current TTO sample was determined by GC/MS and NMR. The level of cytotoxicity in TTO treated cultures was determined by decrease of mitotic index when compared to that in negative control. The genotoxic potential of TTO was assessed by the in vitro mammalian cell micronucleus and the chromosome aberrations (CA) tests.

Results

Twenty-seven compounds were identified, accounting for 98.9% of the constituents. Terpinen-4-ol (42.8%), γ-terpinene (20.4%), p-cymene (9.6%), α-terpinene (7.9%), 1,8-cineole (3%), α-terpineol (2.8%) and α-pinene (2.4%) were the major compounds of the oil sample. None of the tested TTO concentrations (95 μg/ml, 182 μg/ml and 365 μg/ml) caused a significant increase in the observed frequencies of micronuclei when compared to those in the untreated cultures (negative control). Additionally, no significant differences regarding the frequencies of CA were observed among the tested TTO concentrations and the negative control.

Conclusions

Results demonstrate that TTO, in the tested concentrations, is not genotoxic in in vitro mammalian cells.  相似文献   
39.
目的 通过探讨茶及其有效成分对肝癌细胞HepG2增殖的影响,为乌龙茶成分进一步开发提供有力的实验室证据.方法 体外培养人肝癌细胞株HepG2,加入浓度为25、50、100和200 mg/L的茶叶浸出液、茶多酚、茶色素、茶多糖、茶氨酸作用24h后,用水溶性四唑盐(WST-1)检测肝癌细胞的存活率.结果 乌龙茶及其有效成分对肝癌细胞HepG2进行干预后,各组肝癌细胞的增殖均被抑制,各组的吸光度值均低于阴性对照组,茶汤100 mg/L组和200 mg/L组、茶多酚各组和茶色素各组、茶多糖和茶氨酸50mg/L、100 mg/L和200 mg/L组,与阴性对照组比较,差异均有统计学意义(均P<0.05).同时茶多酚25 mg/L组、茶色素25 mg/L组与茶汤25 mg/L组比较,差异均有统计学意义[(0.1658±0.0025)、(0.1913±0.0013)比(0.2005±0.0013),均P<0.05];茶多酚50mg/L组、茶色素50mg/L组、茶多糖50 mg/L组、茶氨酸50 mg/L组与茶汤50 mg/L组比较,差异均有统计学意义[(0.1545±0.0041)、(0.1655±0.0039)、(0.1595±0.0019)、(0.1728 ±0.0040)比(0.1970 ±0.0078),均P<0.05];茶多酚100 mg/L组(0.1370±0.0016)与茶汤100 mg/L组(0.1600 ±0.0037)比较,差异有统计学意义(P<0.05).结论 乌龙茶及其有效成分对人肝癌细胞HepG2具有明显的抑制作用,表现出抗肝癌的作用.  相似文献   
40.
The study investigates the antioxidant characteristics of various white teas steeped in either hot or room-temperature water in relation to grade of tea and brewing conditions. Antioxidant activity, chelating activity, total phenol (TPC), flavonoids (TFC), theaflavins and individual catechin content were examined. The results confirm that extraction of tea leaves carried out with water at room temperature leads to the formation of infusions particularly rich in compounds with antioxidant activity. In fact, for all the white teas studied, cold infusions had a higher content of phenols (4.77–7.63 mmol/L Gallic Acid Equivalents, GAE), flavonoids (1.47–2.53 mmol/L Catechin Equivalents, CE) and catechins (441.5–1328.2 μg/mL) compared to hot infusions (1.43–4.02 mmol/L GAE, 0.70–1.13 mmol/L CE, 83.4–534.8 μg/mL, respectively). The same trend was also observed for antioxidant activities examined using the ABTS assay (cold: 17.09–34.23; hot: 5.26–17.07 mmol/L Trolox Equivalents) and by monitoring the effects of the infusions on LDL oxidation (lag time, cold: 172.4–271.2; hot: 88.4–145.9 min). A general trend in antioxidant activity and in polyphenolic compound content can be delineated between Chinese teas, i.e. Bai Mu Dan  Xue Ya  White Lung Ching > Anji Needle Mao Feng > Yhin Zhen Bai Hao and between African teas, i.e. White Salima Peony > Thyolo Bsp > Bvumbwe Bsp. Concerning metal chelating activity, all the white teas displayed similar levels (0.3–0.6 mmol/L EDTA Equivalents) with no significant differences between the hot and cold infusions (except Bvumbwe Bsp and Thyolo Bsp). This paper contains key information on the antioxidant properties, TPC, TFC, and individual catechin content of several white teas commercially available and the outcomes suggest that preparing tea infused in room temperature water for approximately 2 h may constitute an alternative tea beverage potentially richer in healthful bioactive compounds compared to the more commonly consumed hot tea infusions.  相似文献   
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