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41.
Water quality and the distribution of some heavy metals in three different organs of Lepomis gibbosus from the Cine Stream were studied. Also, histopathological changes in gill, liver, and muscle tissue were examined at light microscopical level. Micronucleus (MN) formation in fish erytrocytes, as an indicator of chromosomal damage, has been increasingly used to detect the genotoxic potential of environmental contaminants. The frequency of MN was examined from samples of fish from the Cine Stream and a control group. MN frequency was higher in fish samples caught from the Cine Stream than that in the control group. The chemicals ammonia, nitrite, nitrate, orthophosphate, and sulphate were determined as parameters that possibly affect the gill, liver, and muscle morphology. Zn was the most accumulated metal in tissues as well as in water. Maximum metal accumulation occurred in both liver and gills. For histopathological examinations, samples of gills, liver, and muscle tissues of L. gibbosus were studied by using light microscopy. In this study, a significant decrease in mean length of primary and secondary lamellae were observed. Moreover, cellular proliferation developed with secondary lamellae fusion, ballooning degenerations or club deformation of secondary lamellae, as well as distribution of necrotic, hyperplastic and clavate secondary lamellae. In the liver, altered staining, swollen and ruptured parenchymal cells, loss of cord structure, reduce of glycogen in hepatocytes, and vacuolar structure filled with cellular debris and many dark particles were seen. In muscle tissue, focal necrosis, cellular dissolution, and a decline or loss of striation in muscle fibres were found.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Um die Ausbreitung von SARS-CoV‑2 (schweres akutes Atemwegssyndrom-Coronavirus-Typ 2) zu verlangsamen, haben Bund...  相似文献   
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Background: Aminoglycoside antibiotics, including gentamicin, despite their ability to induce adverse effects on pigmented tissues, remain valuable and sometimes indispensable for the treatment of various infections. It is known that gentamicin binds to melanin biopolymers, but the relation between this drug affinity to melanin and its toxicity is not well documented. The aim of this work was to examine the impact of gentamicin on viability and melanogenesis in HEMa-LP (light pigmented) and HEMn-DP (dark pigmented) normal human melanocytes.

Methodology/principal findings: The effect of gentamicin on cell viability was determined by 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate (WST-1) assay; melanin content and tyrosinase activity were measured spectrophotometrically. It has been demonstrated that gentamicin induces concentration-dependent loss in melanocytes viability. The application of antibiotic in concentration of 10?mM causes higher reduction in viability of the light pigmented melanocytes (by about 74%) when compared with the dark pigmented ones (by about 62%). The value of the concentration of a drug that produces loss in cell viability by 50% (EC50) for both cell lines was found to be ~7.5?mM. It has been shown that gentamicin causes inhibition of tyrosinase activity and reduces melanin content in light pigmented melanocytes significantly more than in the dark pigmented cells.

Conclusion/significance: We have found that gentamicin modulates melanization process in melanocytes in vitro, what may explain the potential role of melanin biopolymer in the mechanisms of undesirable toxic effects of this drug in vivo, as a result of its accumulation in pigmented tissues. We have also stated that the melanogenesis process in light pigmented melanocytes is more sensitive to the inhibitory effect of gentamicin than in the dark pigmented cells.  相似文献   
44.
用混合凝胶电泳法 ,调查长沙地区 2 34名汉族人群GLOⅠ表型频率分布。发现三种GLOⅠ表型 ,其基因频率为GLOⅠ1 =0 .1 30 3 ,GLOⅠ2 =0 .8697。与不同地区、不同国家和民族相比较。检测不同条件下的血痕标本 ,发现室温下 (2 0~ 30℃ )保存的 2 0例纱布血痕 40d内可全部正确分型 ,低温 0~ 4℃保存的 2 0例纱布血痕至少 1 0 0d也可全部正确分型。日晒、水洗等因素可影响血痕GLOⅠ型的正确检出  相似文献   
45.
The aim of this study was to compare the biological activities of ethanolic propolis extracts of Apis mellifera caucasica obtained from Ardahan and Erzurum provinces of Turkey. Samples were tested for antioxidant, anticytotoxic, anticarcinogenic, antibacterial, and antifungal potentials using different techniques. Propolis samples from the two provinces had different mineral and organic compositions related to their geographical origin. The ferric reducing antioxidant power (FRAP) test showed superiority of Ardahan propolis over the Erzurum. Regardless of origin and the presence of mitomycin C in the culture medium, propolis enhanced human peripheral lymphocyte viability, which depended on the duration and propolis concentration. Antiperoxidative activity on MCF-7 breast cancer cells was concentration-dependent. Erzurum propolis showed the highest anticarcinogenic activity at the concentrations of 62.5 μg/mL and 125 μg/ mL, which dropped at higher concentrations. All propolis samples also showed antibacterial activity against the tested human pathogens similar to ampicillin and penicillin controls, except for Pseudomonas aeruginosa. However, they did not exert any antifungal activity against Candida albicans and Yarrowia lipolytica. In conclusion, propolis samples from both provinces showed promising biological activities, but further research should focus on finding the right concentrations for optimal effect and include the cell necrosis pathway to get a better idea of the anticarcinogenic effects.Key words: anticarcinogen, antimicrobial, biological activity, mineral, mitomycin C, organic composition  相似文献   
46.
Aminoglycosides, such as amikacin and kanamycin, are powerful broad-spectrum antibiotics used for the treatment of many bacterial infections. The widely used aminoglycosides have the unfortunate side effects of targeting sensory hair cells of the inner ear, so that treatment often results in permanent hair cell loss. The aim of the study was to evaluate the influence of incubation time and drug concentration on viability of melanocytes cultured in the presence of amikacin or kanamycin. The normal human melanocytes HEMa-LP and the different concentrations of amikacin (0.075, 0.75 and 7.5 mmol/l) and kanamycin (0.06, 0.6 and 6.0 mmol/l), were used. The estimations were performed after 24, 48 and 72 h. The observed decrease in melanocytes viability may be an explanation for the mechanisms involved in aminoglycosides toxicity on pigmented tissues during high-dose and/or long-term therapy.  相似文献   
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Background: Because of its high density and viscosity, xenon (Xe) may influence respiratory mechanics when used as an inhaled anesthetic. Therefore the authors studied respiratory mechanics during xenon and nitrous oxide (N2O) anesthesia before and during methacholine-induced bronchoconstriction.

Methods: Sixteen pentobarbital-anesthetized pigs initially were ventilated with 70% nitrogen-oxygen. Then they were randomly assigned to a test period of ventilation with either 70% xenon-oxygen or 70% N2O-oxygen (n = 8 for each group). Nitrogen-oxygen ventilation was then resumed. Tidal volume and inspiratory flow rate were set equally throughout the study. During each condition the authors measured peak and mean airway pressure (Pmax and Pmean) and airway resistance (Raw) by the end-inspiratory occlusion technique. This sequence was then repeated during a methacholine infusion.

Results: Both before and during methacholine airway resistance was significantly higher with xenon-oxygen (4.0 +/- 1.7 and 10.9 +/- 3.8 cm H2O [middle dot] s-1 [middle dot] l-1, mean +/- SD) when compared to nitrogen-oxygen (2.6 +/- 1.1 and 5.8 +/- 1.4 cm H2O [middle dot] s-1 [middle dot] l-1, P < 0.01) and N2O-oxygen (2.9 +/- 0.8 and 7.0 +/- 1.9, P < 0.01). Pmax and Pmean did not differ before bronchoconstriction, regardless of the inspired gas mixture. During bronchoconstriction Pmax and Pmean both were significantly higher with xenon-oxygen (Pmax, 33.1 +/- 5.5 and Pmean, 11.9 +/- 1.6 cm H2O) when compared to N2O-oxygen (28.4 +/- 5.7 and 9.5 +/- 1.6 cm H2O, P < 0.01) and nitrogen-oxygen (28.0 +/- 4.4 and 10.6 +/- 1.3 cm H2O, P < 0.01).  相似文献   

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