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41.
Endotoxin contamination was measured in washed and unwashed cottons from three distinct growing areas, California, Mississippi, and Texas. The data show differences in endotoxin contamination based upon the geographic source of the cotton. It is also shown that washing bulk cotton before the carding process results in lower endotoxin in the cotton dust. Washing conditions can affect the endotoxin levels, and all size fractions of the airborne dust contain quantifiable endotoxin contamination. Endotoxin analyses provide a simple and reliable method for monitoring the cleanliness of cotton or airborne cotton dusts.  相似文献   
42.
Electron microscopic observations on pinealocytes of cotton rats (Sigmodon bispidus) killed in October revealed the presence of cytoplasmic inclusion bodies (CIBs) and two kinds of nuclear inclusions--coiled bodies and granular inclusion bodies. These inclusions were usually not bounded by a membrane. CIBs showed round or irregular profiles and consisted of granular and filamentous materials of moderate electron opacity intermingled with electron-lucent areas. Nuclear granular inclusions appeared as homogeneous or heterogeneous granules of variable electron opacity, which usually exhibited round profiles of variable diameters and consisted of granular and filamentous elements. Electron-opaque granules were observed in perinuclear spaces, dilated cisternae of rough endoplasmic reticulum, as well as in the central portion of CIBs. In CIBs containing granules, the peripheral region was composed of the moderately electron-opaque substance seen in usual CIBs, while the central core was occupied by a granular and filamentous substance and an intervening electron-lucent matrix. Since an electron-opaque granular substance in nuclei, perinuclear spaces, cisternae of rough endoplasmic reticulum, and the central portion of CIBs may occur concomitantly, the granules seen in these sites may be related. Coiled bodies were round in profile and were composed of electron-opaque strands consisting of granular and filamentous elements and intervening material of low electron opacity. This structure, frequently located in close proximity to the nuclear granular inclusions, may play a role in the formation of the intranuclear granules in cotton rat pinealocytes.  相似文献   
43.
This study evaluated the antiinflammatory activities of pinitol and glucosamine either alone or in combination against carrageenan- and cotton pellet-induced acute and subacute inflammation in rats. Five groups were included in each of the acute and subacute inflammation studies: the vehicle control group, positive control group (aminopyrine 100 mg/kg), pinitol group (20 mg/kg), glucosamine group (25 mg/kg) and a pinitol (20 mg/kg) and glucosamine (25 mg/kg) combination group. When 20 mg/kg of pinitol was administered to the rats, paw edema induced by the carrageenan injection was significantly suppressed and the level of granuloma formation induced by the cotton pellet implantation was slightly reduced. When 25 mg/kg of glucosamine was administered, paw edema caused by the acute inflammation was slightly reduced and the level of granuloma formation caused by the subacute inflammation was strongly suppressed. Although the combined application of pinitol and glucosamine did not have an additional antiinflammatory effect on the paw edema caused by acute inflammation, it did have an increased antiinflammatory effect on the formation of granuloma induced by subacute inflammation. Therefore, pinitol and glucosamine have an antiinflammatory effect on acute and subacute conditions. Moreover, a synergistic antiinflammatory effect against subacute inflammation was observed when the two chemicals were administered in combination.  相似文献   
44.
In this study, the aqueous (AQJP) and alcoholic (ALJP) extracts of the whole plant of Justicia prostrata Gamble (Acanthaceae) were screened for their acute and subacute anti-inflammatory activities using carrageenan-induced acute inflammation and cotton-pellet-induced granuloma (subacute inflammation), respectively, in rats. In the carrageenan-induced rat paw oedema model, both extracts were found to exhibit maximum reduction in paw volume at the first hour in a dose-dependent manner. At the dose of 500 mg/kg p.o., both extracts AQJP and ALJP showed maximum inhibition (51.39% and 62.5%, respectively) in rat paw oedema volume at the first hour of carrageenan-induced acute inflammation. In the cotton pellet granuloma assay, AQJP and ALJP at the dose of 500 mg/kg p.o. suppressed the transudative, exudative and proliferative phases of chronic inflammation. These extracts were able to (i) reduce the lipid peroxide content of exudates and liver and (ii) normalize the increased activity of acid and alkaline phosphatases in serum and liver of cotton pellet granulomatous rats. Preliminary phytochemical screening revealed the presence of lignans, triterpenes and phenolic compounds in ALJP, whereas phenolic compounds and glycosides in AQJP. The anti-inflammatory properties of these extracts may possibly be due to the presence of phenolic compounds. The anti-inflammatory effects produced by the extracts at the dose of 500 mg/kg, p.o. was comparable with the reference drug diclofenac sodium (5 mg/kg p.o.).  相似文献   
45.
Transposable elements, particularly LTR-retrotransposons, comprise the primary vehicle for genome size expansion in plants, while DNA removal through illegitimate recombination and intrastrand homologous recombination serve as the most important counteracting forces to plant genomic obesity. Despite extensive research, the relative impact of these opposing forces and hence the directionality of genome size change remains unknown. In Gossypium (cotton), the 3-fold genome size variation among diploids is due largely to copy number variation of the gypsy-like retrotransposon Gorge3. Here we combine comparative sequence analysis with a modeling approach to study the directionality of genome size change in Gossypium. We demonstrate that the rate of DNA removal in the smaller genomes is sufficient to reverse genome expansion through Gorge3 proliferation. These data indicate that rates of DNA loss can be highly variable even within a single plant genus, and that the known mechanisms of DNA loss can indeed reverse the march toward genomic obesity.  相似文献   
46.
47.
Fatty acyl‐CoA reductases (FARs), the enzymes that catalyse reduction of a fatty acyl‐CoA to the corresponding alcohol in insect pheromone biosynthesis, are postulated to play an important role in determining the proportion of each component in the pheromone blend. For the first time, we have isolated and characterized from the Egyptian cotton leaf worm Spodoptera littoralis (Lepidoptera: Noctuidae) a FAR cDNA (Slit‐FAR1), which appeared to be expressed only in the pheromone gland and was undetectable in other female tissues, such as fat body, ovaries, wings, legs or thorax. The encoded protein has been successfully expressed in a recombinant system, and the recombinant enzyme is able to produce the intermediate fatty acid alcohols of the pheromone biosynthesis of S. littoralis from the corresponding acyl‐CoA precursors. The kinetic variables Km and Vmax, which have been calculated for each acyl‐CoA pheromone precursor, suggest that in S. littoralis pheromone biosynthesis other biosynthetic enzymes (e.g. desaturases, acetyl transferase) should also contribute to the final ratio of components of the pheromone blend. In a phylogenetic analysis, Slit‐FAR1 appeared grouped in a cluster of other FARs involved in the pheromone biosynthesis of other insects, with little or non‐specificity for the natural pheromone precursors.  相似文献   
48.
49.
Over the last few decades, a number of natural dyes have become non-toxic, eco-friendly and biocompatible substitutes of highly carcinogenic synthetic dyes. Herein, we selected the Acalypha wilkesiana (copper plant) as the source of a natural colorant for auxiliary-free dyeing of cotton, a way forward to eco-friendly dyeing. The bioactive phytochemical constituents of this plant include tannins, flavonoids, phlobatanins, cardiac glycosides, saponins, alkaloids, terpenes and steroids. Both the aqueous and methanol extracts of copper leaf were extracted and applied to unmodified and modified cotton fabrics with the percentage shade depths of 0.5%, 1%, 2%, 4%, 5% and 6% both at pH 4 and 7. The cationized samples rendered substantial improvement in color strength (K/S) values as compared to un-cationized ones. Aqueous and methanolic extracts offered very similar K/S values on cationized samples. Without using any metallic salts as mordants, the color fastness properties like rubbing fastness, washing fastness were also slightly improved due to greater dye fixation on cationized samples compared to uncationized ones. In conclusion, the aqueous extract exhibited dye fixation and color fastness properties comparable to methanolic extract at pH 4 and 7. Thus, it suggested the avoidance of toxic organic solvent for extraction and auxiliary chemicals in subsequent dyeing, a step towards eco-friendly sustainable dyeing.  相似文献   
50.
霍山石斛的抗炎作用   总被引:1,自引:0,他引:1  
目的:观察霍山石斛的抗炎作用。方法:60只昆明种小鼠,随机分为正常组、模型组、石斛高、中、低剂量组(4,2,1 g·kg~(-1)),醋酸地塞米松组(醋酸地塞米松,0. 01 g·kg~(-1));连续灌胃给药14 d;末次给药1 h后,于小鼠右耳的耳中部两侧滴二甲苯20μL建立耳肿胀模型。1 h后断头处死所有小鼠,计算各组小鼠耳肿胀率。健康SD大鼠36只,分别为正常组、模型组、霍山石斛高、中、低(2. 8,1. 4,0. 7 g·kg~(-1))剂量组、醋酸地塞米松组。连续灌胃给药7 d。末次灌胃给药1 h后,于各组大鼠的右后肢足趾皮下注射10%新鲜鸡蛋清建立足肿胀模型。分别于0,0. 5,1,2,3,4,5 h时,测量各大鼠的右后足周长,计算大鼠的足肿胀度。取SD大鼠60只,向双侧腹股沟皮下植入无菌干燥棉球,分组同上。第2天灌胃给药,连续14 d。末次给药后,取出棉球,计算肉芽肿抑制率;检测各组大鼠血清中肿瘤坏死因子-α(TNF-α),白细胞介素-1β(IL-1β),白细胞介素-2(IL-2),白细胞介素-6(IL-6),γ-干扰素(IFN-γ)含量。结果:与正常组比较,模型组耳肿胀率、足肿胀度显著升高(P 0. 01);与模型组比较,霍山石斛高、中、低剂量组均可明显降低小鼠耳肿胀率(P 0. 01);霍山石斛高、中剂量组足肿胀度明显降低(P0. 05,P 0. 01);给药各组棉球肉芽干重显著下降(P 0. 01),胸腺、脾脏指数没有显著性变化;与正常组比较,模型组大鼠血清中炎症因子含量显著升高(P 0. 01);与模型组比较,霍山石斛高、中、低剂量组和醋酸地塞米松组炎症因子含量显著降低(P 0. 05,P 0. 01)。结论:霍山石斛能够有效抑制急、慢性炎症反应。  相似文献   
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