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121.
Cyclophosphamide (CP) is a common anticancer drug, but its use in cancer treatment is limited due to its severe toxicities induced mainly by oxidative stress in normal cells. Reactive oxygen species (ROS) lead to multiple organ injuries, including the kidneys. Selenium (Se) is a nutritionally essential trace element with antioxidant properties. In the present study, the possible protective effect of Se on CP-induced acute nephrotoxicity was investigated. Forty-two Sprague-Dawley rats were equally divided into six groups of seven rats in each. The control group received saline, and other groups were injected with CP (150 mg/kg), Se (0.5 or 1 mg/kg), or CP + Se intraperitoneally. Total antioxidant capacity (TAC), total oxidant state (TOS), oxidative stress index (OSI), creatinine, and cystatin C (Cys C) levels were measured in the sera. In addition, kidney tissues were examined histologically. In the CP alone treated rats, creatinine, Cys C, TOS, and OSI levels increased, while TAC level decreased. CP-induced histological damages were decreased by co-treatment of Se and biochemical results supported the microscopic observations. In conclusion, our study points to the therapeutic potential of Se and indicates a significant role of ROS in CP-induced kidney toxicity.  相似文献   
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123.
ObjectivesEliminating unnecessary laboratory tests is a good way to reduce costs while maintain patient safety. The aim of this study was to define and process strategies to rationalize laboratory use in Ankara Numune Training and Research Hospital (ANH) and calculate potential savings in costs.MethodsA collaborative plan was defined by hospital managers; joint meetings with ANHTA and laboratory professors were set; the joint committee invited relevant staff for input, and a laboratory efficiency committee was created. Literature was reviewed systematically to identify strategies used to improve laboratory efficiency. Strategies that would be applicable in local settings were identified for implementation, processed, and the impact on clinical use and costs assessed for 12 months.ResultsLaboratory use in ANH differed enormously among clinics. Major use was identified in internal medicine. The mean number of tests per patient was 15.8. Unnecessary testing for chloride, folic acid, free prostate specific antigen, hepatitis and HIV testing were observed. Test panel use was pinpointed as the main cause of overuse of the laboratory and the Hospital Information System test ordering page was reorganized. A significant decrease (between 12.6–85.0%) was observed for the tests that were taken to an alternative page on the computer screen. The one year study saving was equivalent to 371,183 US dollars.ConclusionHospital-based committees including laboratory professionals and clinicians can define hospital based problems and led to a standardized approach to test use that can help clinicians reduce laboratory costs through appropriate use of laboratory tests.  相似文献   
124.
Many organisms live in populations structured by space and by class, exhibit plastic responses to their social partners, and are subject to nonadditive ecological and fitness effects. Social evolution theory has long recognized that all of these factors can lead to different selection pressures but has only recently attempted to synthesize how these factors interact. Using models for both discrete and continuous phenotypes, we show that analyzing these factors in a consistent framework reveals that they interact with one another in ways previously overlooked. Specifically, behavioral responses (reciprocity), genetic relatedness, and synergy interact in nontrivial ways that cannot be easily captured by simple summary indices of assortment. We demonstrate the importance of these interactions by showing how they have been neglected in previous synthetic models of social behavior both within and between species. These interactions also affect the level of behavioral responses that can evolve in the long run; proximate biological mechanisms are evolutionarily stable when they generate enough responsiveness relative to the level of responsiveness that exactly balances the ecological costs and benefits. Given the richness of social behavior across taxa, these interactions should be a boon for empirical research as they are likely crucial for describing the complex relationship linking ecology, demography, and social behavior.  相似文献   
125.
126.
The aim of this study is to investigate the phytochemical contents and antibacterial properties of 2-year Prunus avium L. standard cultivars [Cristalina (Cr), 0900 Ziraat (Zr)] and to elucidate the mechanism of action of the extracts on the quorum sensing (QS) system by using homology modelling and molecular docking. Phenolic contents of methanol extract of Cr and Zr stalks were detected by HPLC. As a result, catechin hydrate (6364·67–8127·93 µg g−1) and chlorogenic acid (998·81–1273·4 µg g−1) were found to be the highest in stalk extracts in the two varieties in 2017. All extracts had inhibitory effect on Gram-positive bacteria. Stalk extract of Zr showed higher inhibition rate (86%) on swarming motility. Stalk samples of Zr collected in 2017 and 2018 also reduced biofilm formation by 75 and 73%, respectively. The computational analysis revealed that one of the major component of the extracts, chlorogenic acid, was able to bind to the QS system receptors, LasR, RhlR, and PqsR. Therefore, the mechanism of decreasing the production of virulence factors by the extracts might be through inhibiting these receptors and thus interfering with the QS system.  相似文献   
127.
Interactions with stromal components influence the growth, survival, spread, and colonization capacities of tumor cells. Fibroblasts and macrophages which are responsible for the stroma production and maintenance are of the basic elements found in tumor microenvironment. Cellular density and ratio of stromal cells to tumor cells can also have modulatory effects in cancer. Here, the contribution of fibroblast and/or macrophage cells on the malignant behavior of breast cancer cells was modeled in co-culture systems. Co-cultures were established at different cell densities and ratios with 4T1 breast cancer, NIH/3T3 or 3T3-L1 fibroblast, and J774A.1 monocyte/macrophage cell lines. Flow cytometry-based proliferation, 3D growth on alginate matrix, and matrigel invasion assays were performed to determine the change in the malignant assets of tumor cells. The data were also supported by immunocytochemical and morphological analyses. Co-culturing with fibroblasts (especially, NIH/3T3 cells) significantly supported the proliferation, scattering, and invasiveness of 4T1 cells whereas inclusion of macrophages disrupted this positive influence. On the other hand, the invasion capacity of 4T1 cells was not enhanced in the co-cultures with fibroblasts whose motility were inhibited with pertussis toxin pretreatment. Particularly at low-density seeding in 3D cultures, 4T1 cells could form substantially more spheroids than that of in the co-cultures with fibroblasts. Only, increasing the amount of fibroblasts could restore the 3D-growth. Intriguingly, co-existence of macrophage, fibroblast, and tumor cells in 3D cultures provided a convenient stroma sustaining the spheroid formation and growth. In conclusion, fibroblasts can form a favorable environment for tumor cells’ spread and motility whereas restricting their 3D-growth capacity. On the other hand, presence of macrophages may disrupt the influence of fibroblasts and enhance the spheroid formation by the tumor cells.  相似文献   
128.

Objective

Interleukin-4 (IL-4) is a strong chondroprotective cytokine and polymorphisms within this gene may be a risk factor for osteoarthritis (OA). We aimed to investigate genotype and allele frequencies of IL-4 gene intron 3 variable number of tandem repeats (VNTR) polymorphism in patients with knee OA in a Turkish population.

Methods

The study included 202 patients with knee OA and 180 healthy controls. Genomic DNA was isolated and IL-4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers followed by restriction fragment length polymorphism (RFLP) analysis.

Results

Our result show that there was statistically significant difference between knee OA patients and control group with respect to IL-4 genotype distribution and allele frequencies (p = 0.000, OR: 0.20, 95% CI: 0.10–0.41, OR: 0.22, 95% CI: 0.12–0.42, respectively).

Conclusions

Our findings suggest that there is an association of IL-4 gene intron 3 VNTR polymorphism with susceptibility of a person for development of knee OA. As a result, IL-4 gene intron 3 VNTR polymorphism could be a genetic marker in OA in a Turkish study population. This is the first association study that evaluates the associations between IL-4 gene VNTR polymorphism and knee OA.  相似文献   
129.
We investigated the cytotoxic, neurotoxic, apoptotic and antiproliferative effects of extracts from Petalonia fascia, Jania longifurca and Halimeda tuna on the MCF-7 breast cancer cell line. J. longifurca extracts were more toxic than those of P. fascia and H. tuna. The algal extracts showed significant toxic effects at different dilutions. The toxic effects were due to increased oxidative stress and resulted in apoptosis. Algal toxicity may exert negative effects through the food chain or by direct interaction. Algal toxicity also has potential for cancer therapy. The toxic effects that we observed may be especially important for therapy for breast tumors.  相似文献   
130.
Benzimidazoles of both natural and synthetic sources are the key components of many bio-active compounds. Several reports have shown antifungal, antiviral, H(2) receptor blocker and antitumor activities for benzimidazoles and their derivatives. In this study, we synthesized twelve bis-benzimidazole derivatives by selecting di(1H-benzo[d]imidazol-2-yl)methane as the main compound. The numbers of carbons at 2 positions of bis-benzimidazole derivatives were changed from 1 to 4, and derivatives were synthesized with methyl substitutions at 5- and/or 6- positions. The compounds were screened via in vitro plasmid superciol relaxation assays using mammalian DNA topoisomerase I and cytostatic assays were carried out against HeLa (cervix adenocarcinoma), MCF7 (breast adenocarcinoma) and A431 (skin epidermoid carcinoma) cells for selected derivatives. Our results suggest that the malonic acid derivatives of bis-benzimidazoles, namely, bis(5-methyl-1H-benzo[d]imidazol-2-yl)methane and bis(5,6-dimethyl-1H-benzo[d]imidazol-2-yl)methane, were remarkably active compounds in interfering with DNA topoisomerase I and the former compound was also found to be cytotoxic against MCF7 and A431 cells. The inhibitory effects obtained with these derivatives are significant as these compounds can be potential sources of anticancer agents.  相似文献   
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