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31.
设置了5个氮素浓度梯度(N0、N1、N2、N3、N4)、3个PEG(P0、P1、P2)浓度梯度以及2个CO2浓度(370±50 μmol·mol-1; 700±50 μmol·mol-1)水平的盆栽试验,探究了小麦幼苗生长、物质积累与分配以及植株水分条件的变化规律。结果表明:小麦幼苗株高、地上部干重、根干重、生物量以及叶水势的最大值以及高浓度CO2的最大刺激作用均出现在处理N1P0; 而根长和根冠比的最大值分别出现在处理N0P0和N1P2,高浓度CO2的最大刺激值也分别出现在处理N0P0和N1P2; 适宜养分条件下,高浓度CO2能够最大限度地促进小麦幼苗的生长,同时高浓度CO2通过提高小麦幼苗叶水势,一定程度上缓解了低浓度PEG胁迫的不利影响。因此,未来CO2浓度升高将对水肥条件好的小麦产生促进作用,可缓解轻度水分不足的不利影响,而对严重干旱胁迫下小麦的生长作用不明显。  相似文献   
32.
成利娟  葛朝亮  杨翠  刘铭  许杜娟 《安徽医药》2015,19(10):1849-1852
目的:观察小麦胚芽油(wheat germ oil,WGO)对动脉粥样硬化(atherosclerosis,AS)大鼠的治疗效果,并探讨其抗 AS 的可能作用机制。方法连续高脂乳剂灌胃4周,制作 AS 大鼠模型,分别给予各组大鼠连续灌胃不同剂量 WGO 8周;HE 染色光镜下观察大鼠主动脉弓病理形态的改变;酶联免疫吸附试验(ELISA)法检测各组大鼠血清中前列环素(Prostacyclin 2, PGI2)、血栓素 A2(Thromboxane 2,TXA2)及内皮素-1(Endothelin-1,ET-1)的含量。结果2.0 g·kg -1的 WGO 能明显改善 AS大鼠主动脉弓的病理状态,基本恢复正常状态;与模型组比较,1.0、2.0 g·kg -1 WGO 均可显著提高 AS 大鼠血清中 PGI2含量,明显降低 TXA2、ET-1水平(P <0.05)。结论WGO 能明显改善 AS 大鼠的动脉粥样硬化状态。其作用机制可能为小麦胚芽油具有良好的调节 PGI2、TXA2平衡,抑制血栓形成,修复内皮损伤以及较强的抗氧化作用。  相似文献   
33.
Context: Allergy to hydrolyzed wheat protein in facial soap has become a major social issue in Japan. It has been reported that the most frequent early symptoms of allergy to hydrolyzed wheat protein in soap are allergic conjunctivitis and rhinitis, while wheat-dependent exercise-induced anaphylaxis can be induced by long-term use.

Objective: We evaluated the relation between tear fluid levels of specific IgE for wheat and the features of allergic conjunctivitis.

Methods: A prospective, non-randomized, cross-sectional study was conducted in 103 patients with moderate to severe allergic conjunctivitis (allergic group) and 20 age- and sex-matched healthy control subjects (control group). Specific IgE for wheat was measured in tear fluid with an immunochromatography assay, and a skin prick test (SPT) was also performed. Symptoms (sneezing, rhinorrhea, nasal obstruction, ocular itching, and lacrimation) were assessed in each subject along with the activities of daily living (ADL) score and the total ocular symptom score for allergic conjunctivitis. A severity score (0, 1, 2, or 3) was assigned for various changes of the palpebral and bulbar conjunctiva, as well as for limbal and corneal lesions associated with allergic conjunctivitis.

Results: The IgE positive rate and specific IgE score were both higher in the allergic group than in the control group (71.8% versus 40.0% and 1.9?±?0.7 versus 1.4?±?0.5). A positive SPT for wheat was also more frequent in the allergic group than in the control group (6.8% versus 0.0%). Within the allergic group, patients with a positive SPT had higher specific IgE scores than patients with a negative SPT (3.3?±?0.5 versus 1.8?±?0.6, p?wheat IgE level in tear fluid was correlated with the severity of allergic conjunctivitis symptoms, including ocular itching (r?=?0.665), tearing (r?=?0.672), and the total ocular symptom score (r?=?0.204). Wheat IgE in tear fluid was also correlated with the severity of rhinitis symptoms, including sneezing (r?=?0.610), nose blowing (r?=?0.640), and nasal obstruction (r?=?0.677). Furthermore, the tear fluid wheat IgE score was correlated with five objective features of allergic conjunctivitis (p?Conclusions: These results suggest that wheat allergy may be involved in the development of allergic conjunctivitis.  相似文献   
34.
The current research work was conducted to characterize wheat proteins through immunochemical techniques and to find out their relationship with wheat quality traits. The results revealed that wheat variety AARI-11 possessed higher protein content (11.96%), wet gluten (31.39%), dry gluten (9.66%), Pelshenke value (190.52 min), and SDS-Sedimentation value (28.27 ml) than other tested varieties. The chapattis prepared from the wheat variety AARI-11 got significantly higher sensory scores owing to its higher protein contents. The wheat variety AARI-11 also exhibited significantly the highest antibody response against all the assessed protein fractions. The results of the present study suggest that anti-glutenin and anti-high molecular weight glutenin subunits (HMW-GS) antibody response was found positively correlated to the quality characteristics of flours and chapattis. The present study suggests that the use of antibodies response against glutenin and HMW-GS offers good tool for predicting quality and suitability of wheat to chapatti-making quality.  相似文献   
35.
The aim of the present research was to modify wheat gluten by binding methionine to gluten proteins to develop bread for celiac disease (CD) patients. The highest protein content, wet gluten content, dry gluten content and sodium dodecyl sulphate-sedimentation value were shown by the wheat variety AARI-11, therefore, it was selected for gluten modification. The bound methionine to gluten proteins was found increasing along the reaction time as the reaction proceeds and at a maximum near to 60 minutes and then it starts decreasing. The lowest immunoreactivity of the modified gluten was obtained near to 60 min of reaction at pH 10. The results for immunoglobulin A (IgA) index showed that the serum of each patient had positive IgA index to gliadins from unmodified gluten, but just sera of two patients had positive IgA index to gliadins from modified gluten and when these proteins were digested, the sera of no patient's serum had positive IgA reactivity. Among physical characteristics of breads 2 hours after baking, the specific volume of the modified gluten containing bread (4.13 ± 0.14 cm3/g) was lower than the control bread (4.59 ± 0.21 cm3/g). However, bread made with modified gluten had higher specific volumes than other gluten-free breads. Texture of the modified gluten was also affected by modification. Finally, the gluten content in the modified gluten bread was 79 ppm which is under the limits set by the Codex Alimentarius for food with reduced gluten content should have from 20 to 100 ppm. The study concludes that the incorporation of steric immensity into gluten proteins in order to shun immune recognition is the most promising approach to acquire wheat-based products that are tolerated by CD patients.  相似文献   
36.
Recovery of gluten in buckwheat flour was evaluated as part of an effort to produce wheat-contaminated buckwheat flours that could be used as reference materials (RMs) for testing the presence of gluten in buckwheat. RMs of buckwheat containing 0, 20, 100 and 1000 ppm gluten were created and tested by ELISA. The Gluten-Check kit detected gluten accurately at all levels; RIDASCREEN and Biokits tests were accurate at 20 and 100 ppm levels, but at 1000 ppm both suffered from extraction saturation effect; Veratox kit read 60% higher for the 20 ppm RM (i.e., 31.9 ppm), but close to the target at 100 ppm RM; Veratox R5 kit showed low accuracy with around 30% recovery at 20 and 100 ppm and some 60% at 1000 ppm level. Overall, the results showed variations in recovery among different test kits which could have important implications in the accurate detection of gluten in buckwheat.  相似文献   
37.
Food allergies are increasing in prevalence, and with it, IgE testing to foods is becoming more commonplace. Food-specific IgE tests, including serum assays and prick skin tests, are sensitive for detecting the presence of food-specific IgE (sensitization), but specificity for predicting clinical allergy is limited. Therefore, positive tests are generally not, in isolation, diagnostic of clinical disease. However, rationale test selection and interpretation, based on clinical history and understanding of food allergy epidemiology and pathophysiology, makes these tests invaluable. Additionally, there exist highly predictive test cutoff values for common allergens in atopic children. Newer testing methodologies, such as component resolved diagnostics, are promising for increasing the utility of testing. This review highlights the use of IgE serum tests in the diagnosis of food allergy.  相似文献   
38.
39.
目的采用Box-Behnken响应面法优化蜜麦麸的制备工艺。方法根据《浙江省中药炮制规范》(2015版)中蜜麦麸制备方法,通过单因素试验筛选影响蜜麦麸制备工艺的关键因素,以麸皮与炼蜜比例、加热温度、加热时间为考察因素,蜜麦麸含水量、堆积密度和色度及阿魏酸含量的总评归一值作为综合指标,利用Box-Behnken设计-响应面法优选蜜麦麸制备工艺,并进行预测分析及工艺验证。结果蜜麦麸最刘制备工艺为麸皮与炼蜜比例为10∶3,加热温度为90℃,加热时间为90 s;含水量、堆积密度、色度、阿魏酸含量均符合蜜麦麸要求,综合指标平均值为0.676 0,与预测值(0.692 7)相对误差为2.41%,相对误差较小。结论优选的制备工艺稳定可靠,且简单可行,适用于蜜麦麸的制备应用。  相似文献   
40.
Recent studies have demonstrated that wheat peptides protected rats against non-steroidal anti-inflammatory drugs-induced small intestinal epithelial cells damage, but the mechanism of action is unclear. In the present study, an indomethacin-induced oxidative stress model was used to investigate the effect of wheat peptides on the nuclear factor-κB(NF-κB)-inducible nitric oxide synthase-nitric oxide signal pathway in intestinal epithelial cells-6 cells. IEC-6 cells were treated with wheat peptides (0, 125, 500 and 2000 mg/L) for 24 h, followed by 90 mg/L indomethacin for 12 h. Wheat peptides significantly attenuated the indomethacin-induced decrease in superoxide dismutase and glutathione peroxidase activity. Wheat peptides at 2000 mg/L markedly decreased the expression of the NF-κB in response to indomethacin-induced oxidative stress. This study demonstrated that the addition of wheat peptides to a culture medium significantly inhibited the indomethacin-induced release of malondialdehyde and nitrogen monoxide, and increased antioxidant enzyme activity in IEC-6 cells, thereby providing a possible explanation for the protective effect proposed for wheat peptides in the prevention of indomethacin-induced oxidative stress in small intestinal epithelial cells.  相似文献   
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