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51.
本实验用纯系CFW小鼠与Wistar大鼠建立“虚证”模型。以环核苷酸系统反应性为指标观察了肉桂挥发油的作用。通过气相色谱及气质联用等方法研究表明,本实验所提取的挥发油中桂皮醛含量约为92%。肉桂挥发油可显著降低“阳虚”——甲状腺素缺乏(甲减)模型升高了的cGMP系统反应性而使其降低了的耗O_2率升高;这是一种治疗作用。肉桂挥发油可显著升高“阴虚”——甲状腺素过多(甲亢)模型已升高了的cAMP系统反应性并使其升高了的耗O_2率进一步升高,这是一种恶化作用。这两种作用与中医对症治疗的原则是一致的。  相似文献   
52.
目的:探讨ω-3鱼油脂肪乳剂对重症胰腺炎患者腹内高压及肠黏膜功能的影响。方法:选择驻马店市中心医院重症医学科收治的136例重症胰腺炎患者作为研究对象,进行前瞻性研究,并按照随机数字表法分为对照组和观察组,各68例。其中对照组给予常规治疗法进行治疗,观察组在上述治疗的基础上外加ω-3鱼油脂肪乳剂进行治疗。观察两组患者治疗后病情缓解时间变化,比较两组患者治疗前后肠黏膜功能指标、趋化因子及腹内压水平变化,分析两组患者治疗效果差异。结果:观察组腹痛缓解时间、腹胀缓解时间、肠鸣音恢复时间以及肛门首次排便时间等病情症状明显改善(均P<0.05)。与治疗前相比,两组治疗后的血清肠型脂肪酸结合蛋白(I-FABP)、二胺氧化酶(DAO)、D-乳酸、中性粒细胞趋化因子(CINC)、FKN、单核细胞趋化因子蛋白-1(MCP-1)及乳果糖/甘露醇(L/M)、腹内压水平明显低于对照组,血清三叶因子(ITF)、乳脂球表皮生长因子8(MFG-E8)明显降低,且观察组改善更显著(均P<0.05)。观察组患者治疗有效率为94.12%,明显高于对照组的76.47%(P<0.05)。结论:ω-3鱼油脂肪乳...  相似文献   
53.
Objective and Design: Whilst the anti-microbial properties of tea tree oil (TTO) are established, the anti-inflammatory effects of TTO in human skin remain largely anecdotal and require evaluation. This study examined the effect of topically applied TTO on nickel-induced contact hypersensitivity reactions in human dorsal skin.Treatment: TTO (100%), a 5% TTO lotion, a placebo lotion (no TTO), or 100% macadamia oil were applied at days 3 and 5 after nickel exposure.Methods: The flare area and erythema index were measured on days 3, 5 and 7. The regulatory effects of TTO were also investigated on the proliferative response to nickel or polyclonal mitogens by peripheral blood mononuclear cells from nickel-sensitive and control subjects.Results: TTO (100%) significantly reduced the flare area and erythema index when compared to the nickel-only sites. With respect to the erythema index, the anti-inflammatory effects were predominantly, but not exclusively, seen in a subgroup of nickel-sensitive subjects with a prolonged development phase of nickel-induced contact hypersensitivity response. The 5% TTO lotion, the placebo lotion and the 100% macadamia oil were all without significant effect. TTO significantly inhibited proliferation to nickel but not to non-specific polyclonal mitogens by peripheral blood mononuclear cells from nickel-sensitive subjects.Conclusions: Topical application of 100% TTO may have therapeutic benefit in nickel-induced contact hypersensitivity in human skin. The mode of action of TTO requires further investigation, but may be an effect on the antigen presenting cells or the antigen presenting process in nickel-induced contact hypersensitivity, as well as vascular changes associated with this response.Received 14 February 2004; returned for revision 30 June 2004; accepted by J. S. Skotnicki 13 September 2004  相似文献   
54.
Effect of acute psychological stress on the inhibition of in vitroplatelet aggregation by dietary long-chain n-3 fatty acids was studied in 20 adult males. Subjects were randomly divided into groups receiving either olive oil or fish oil (2.4 g long-chain n-3 fatty acids/day) for 4 weeks. In vitroaggregation responses to two doses of ADP collagen, and epinephrine were measured immediately prior to and following exposure to three psychological stressors (2 min each), before and after the supplementation period. Olive oil had no effect on baseline aggregatory responses, while fish oil reduced aggregatory responses to ADP and epinephrine. Exposure to the stressors had no effect upon presupplementation aggregation in either group or in the olive oil group postsupplementation. However, stress abolished antiaggregatory effects of fish oil. This reversal of the antiaggregatory effects of fish oil by mild stress suggests possible limitations of low-dose fish oil supplementation in clinical situations.This study was funded by a grant-in-aid from the Heart and Stroke Foundation of Ontario.  相似文献   
55.
This study was intended to determine the number and density of both retinal ganglion cells and the oil droplets of cone photoreceptor cells in brown-eared bulbul (Hysipetes amaurotis). For this study birds were killed with proper dose of anesthetic (pentobarbital, 30 mg/kg), and the eyes were removed from the orbital cavity to isolate the retina. For the ganglion cell study retinal whole-mount specimens were prepared and stained with 0.1% cresyl violet. The different types of oil droplets were counted from color microphotographs of freshly prepared retinal samples. The mean total number of ganglion cells was estimated at approximately 2.5×106; with an average density of 16 523 cells/mm2. Two high-density areas, namely the central area (CA) and the dorso-temporal area (DTA), are located in the central and dorso-temporal retinas, respectively, in bulbuls (24 032 cells/mm2 in the CA; 23 113 cells/mm2 in the DTA). Small ganglion cells persisted in the highest density areas, whereas the largest soma sizes were found in the lowest density areas of the retina. Four types of different colored oil droplets — red, orange, green and clear — were identified with an average density of 29 062/mm2. Among the different colors, the green oil droplets had a significantly higher population (13 083/mm2) than the others across the retina. The central retina had a significantly higher number of all types of oil droplets, at a density of 60 552/mm2. The density and size of the different colored oil droplets were inversely related across the regions of the retina. Taken together, it is concluded that the CA of the retina is an excellent quality area for visual perception due to peak density of ganglion cells and oil droplets. Moreover, each specific oil droplet makes a distinct contribution to visual perception, thereby ensuring that the bird has a retina that best matches its natural environment and feeding behavior.  相似文献   
56.
Summary We present a method whereby, with integrating electronics, quartz patch electrodes and a novel use of silicone oil, background noise levels as low as .083 pA RMS in a 5 kHz bandwidth (4-pole Butterworth filter) have been achieved in single channel patch clamp recordings. These approaches result in much higher signal to noise ratios for single channel recording than have previously been reported and should allow many investigators to significantly reduce noise at a constant bandwidth or to increase their recording bandwidths by several kHz.  相似文献   
57.
胡萝卜籽挥发油的抗生育作用   总被引:3,自引:0,他引:3  
胡萝卜籽挥发油对小鼠有抗着床,抗早、中和晚期妊娠作用。对大鼠也有抗着床作用。挥发油中的萜类碳氢化合物部位,对小鼠皮下注射抗早期妊娠的ED_(50)为2.9ml/kg,甲地孕酮和hCG能明显逆转其作用;对假孕小鼠蜕膜瘤有抑制作用,此作用不能被甲地孕酮拮抗,皮下注射于早孕大鼠24、48小时后血浆孕酮浓度明显下降。以上提示其抗早孕作用机制可能与抑制孕酮合成和蜕膜反应有关。此外,挥发油碳氢部分无雌激素和抗雌激素活性,低浓度时对早孕大鼠离体子宫的收缩活动没有影响,高浓度则表现抑制作用。  相似文献   
58.
The mortality experience of a large refinery cohort (1937-1978) was examined by dividing it into three subcohorts according to hire dates: those hired before 1940, those hired during the period 1940-1945, and those hired after 1945. These three periods are approximately equivalent to before, during, and after World War II and span a total hiring period of more than 75 years. The results showed that a substantial portion of the cohort (3,330 or 27%) had been recruited during 1940-1945, and they contributed 980 or 28% of the total deaths. However, their mortality experience was quite different from the rest. A series of significant increases were seen among the external causes for accidents, suicide, and homicide. In terms of overall mortality and in contrast to the rest of the cohort, no "healthy worker effect" was seen (SMR = 1.00). They also showed increases in several types of cancer including cancers of the pancreas and prostate and leukemia. These unusual experiences cannot be explained either on the basis of their war-related deaths or on their period of employment (one-half were terminated within 1 year from date of hire), and data is insufficient to separate the role of hiring practices or their socioeconomic status. However, their life-styles were probably quite different judged from the fact that alcoholism-related deaths were increased as much as fivefold. Almost two-thirds of the total deaths occurred among 4,080 workers in the before 1940 subcohort. Further, the 5,117 workers of the after-1945 subcohort contributed only 5% of the total deaths. Thus, the results of the original refinery cohort (1937-1978) primarily reflect the experience of those employees hired before 1940. Given the same cohort method (historical prospective), cohort results vary widely according to different study designs, and this has implications for "generalizable" risk assessment or risk projections. A prospective study of new hires with 30 years of follow-up is rather inefficient because it would yield only a small number of deaths, with a strong healthy worker effect. The same is true for studies based on active workers with a short period of follow-up. Studies based on time of hire, however, provide a means for controlling time-related occupational exposures.  相似文献   
59.
Terpene hydrocarbons in Pimpinella anisum L.   总被引:1,自引:0,他引:1  
The essential oil of anise (fruits and shoots) was investigated focusing on the composition of the hydrocarbon fraction. Several sesquiterpenes were identified by GC-MS and the relative composition of the fractions was established by GC analysis. -Himachalene and the diterpene neophytadiene were isolated by TLC and column chromatography at low temperatures. Their structures were determined by MS and NMR including1H-1H correlated COSY and NOE experiments.  相似文献   
60.
紫苏籽油与亚麻籽油合用安全性及降血脂作用研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的 评价紫苏籽油与亚麻籽油合用的安全性及降血脂作用。方法 通过急性经口毒性试验、Ames试验、骨髓细胞微核试验、小鼠精子畸形试验和大鼠30天喂养试验对紫苏籽油与亚麻籽油合用的安全性进行考察;通过建立大鼠混合型高脂血症模型,经口灌胃不同剂量(250、750、1500mg/kg.BW)的紫苏籽油与亚麻籽油混合物连续30天,测定血脂指标,对紫苏籽油与亚麻籽油合用的降血脂作用进行考察。结果 安全性试验结果显示,紫苏籽油与亚麻籽油合用对大、小鼠急性经口MTD值均>15.0g/kg.BW,属无毒级;Ames试验、骨髓细胞微核试验、小鼠精子畸形试验结果均为阴性;30天喂养试验未引起动物中毒性损伤改变。降血脂试验结果显示,与模型对照组比较,紫苏籽油与亚麻籽油合用的三个剂量组的总胆固醇(TC)、甘油三酯(TG)显著降低(F=4.405,P=0.010;F=4.601,P=0.008),降血脂作用明显。结论 紫苏籽油与亚麻籽油合用的安全性高,无致突变性及亚急性毒性,并且具有较好的降血脂作用。  相似文献   
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