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701.
H. S. Salama R. Aboul‐Ela A. El‐Moursy A. Abdel‐Razek 《Biocontrol Science and Technology》1991,1(4):281-287
Exposure of Plodia interpunctella and Sitotroga cerealella to sublethal concentrations of Dipel 2X® (Bacillus thuringiensis var.kurstaki‐HD‐1)with its spores and endotoxin crystals led to an increase in the sum of larval‐pupal duration. A decrease in moth emergence, egg production and fertility was observed with increase of Dipel 2X concentration, while the longevity of the moths was not affected by treatment. Sublethal concentrations of β‐exotoxin (ABG‐6162 A) had no significant effect on the sum of larval—pupal duration of either insect species. Percentage of moth emergence decreased with the increase of β‐exotoxin concentrations. The longevity of both male and female adults of P. interpunctella and of females of S. cerealella were shorter at high concentrations. Egg production in P. interpunctella was reduced by all concentrations of the β‐exotoxin, and hatching of eggs was reduced by concentrations of 15 ppm and above. 相似文献
702.
Kamel H. Shaker Michael Müller M. Abdel Ghani Hans‐Martin Dahse Karlheinz Seifert 《化学与生物多样性》2010,7(8):2007-2015
The new cembrane diterpene (3E,11E)‐cembra‐3,8(19),11,15‐tetraene‐7α‐ol ( 1 ), nephthenol ( 2 ), and all‐trans‐peridinin ( 3 ) have been isolated from the soft coral Litophyton arboreum. The tetraterpene 3 , (+)‐7,8‐epoxy‐7,8‐dihydrocembrene C ( 4 ), emblide ( 5 ), sarcophytoxide ( 6 ), sarcoglaucol‐16‐one ( 7 ), guajacophine ( 8 ), and 1,4‐peroxymuurol‐5‐ene ( 9 ) have been obtained from the soft coral Sarcophyton ehrenbergi. The compounds were characterized primarily by NMR spectroscopy. Some of the terpenes were tested for their antiproliferative activity against the cell lines HUVEC and K‐562 and for cytotoxicity against the cell line HeLa, and they showed moderate activities. 相似文献
703.
Ahmed E. L. Bedewi Randa Youssef Dalia M. Abdel Halim Rehab A. Hegazy William Willis Lisa M. Miller Safinaz S. Sayed Medhat E. L. Mofty 《International journal of peptide research and therapeutics》2013,19(3):209-215
Mycosis fungoides (MF) is the most common type of cutaneous T cell lymphoma in which the distinction between early stage MF and other inflammatory dermatosis remains difficult. Twenty patients of early stage MF and nine patients with psoriasis and lichen planus were included in this study. Ten MF patients were treated with psoralen plus UVA (PUVA) and the other 10 MF patients were treated with PUVA plus methotrexate (MTX) until complete clinical remission. Synchrotron infrared microspectroscopy (SIRM) found that MF lesions were biochemically different compared to inflammatory diseases. After treating MF with either therapeutic modality, the lymphocytic count decreased significantly in both the epidermis and dermis (P < 0.001) but no biochemical changes were observed in the remaining lymphocytes after treatment, indicating the disease process was slowed by treatment but not eradicated. In conclusion SIRM is a promising method for distinguishing MF from other inflammatory diseases such as psoriasis and lichen planus. A significant reduction in lymphocyte count indicated that PUVA therapy is an effective treatment for early stage MF, and MTX could be reserved for more advanced cases that are not PUVA responsive. However, SIRM evidence of persistent disease suggests that maintenance therapy is recommended after clinical remission. 相似文献
704.
Experimental studies have demonstrated the occurrence of angiogenesis, blood vessels formation from pre-existing vessels, in the initial phase of bilharzial granuloma formation and during fibrosis progression in chronic hepatic schistosomiasis. Paradoxically, a recent work demonstrated an occurrence of angiogenesis during fibrosis regression months after curative treatment. Studies regarding the in situ kinetics of blood vessels in the phase of granuloma resolution and liver tissue healing early after treatment are lacking. The current work compared the kinetics of blood vessels by immunohistochemical staining using CD34, vascular endothelial growth factor (VEGF) and actin in the livers of normal control mice, Schistosoma mansoni infected mice and mice 2 weeks after curative treatment. The present study demonstrated a process of angiogenesis remodeling in the liver in the curative phase of hepatic schistosomiasis during the stage of granuloma resolution. Such finding raises the evidence of the importance and potential beneficial effect of vascular proliferation in the process of healing and restoration of liver tissue functions. Thus, blocking of angiogenesis may not represent the appropriate therapeutic target for the early treatment of schistosomal liver fibrosis. 相似文献
705.
An antimicrobial agent is produced by the cyanobacterium Synechococcus leopoliensis which was found to be active against the Gram-positive bacterium Staphylococcus aureus. The effects of temperature, pH, incubation period, some media and different nitrogen and carbon sources on both growth and antimicrobial activity were investigated. Temperature 35 °C and pH 8 were the best for growth and antimicrobial agent production and 14 and 15 days of incubation were found to be the best for maximum growth and antimicrobial activity, respectively, in the medium BG-11.
No antimicrobial activity could be detected by the use of G medium, moderate activity was recorded with Chu 10 medium, while high activity was reported in BG-11 medium. Leucine was the best nitrogen source for antimicrobial activity, while maximum antimicrobial activity was introduced by using the carbon sources, citrate and acetate. Very high antimicrobial activity could be detected by using the carbon source galactose in combination with the nitrogen source alanine or by using arabinose with methionine. 相似文献
706.
ABSTRACT: BACKGROUND: Discovering new biomarkers has a great role in improving early diagnosis of Hepatocellular carcinoma (HCC). The experimental determination of biomarkers needs a lot of time and money. This motivates this work to use in-silico prediction of biomarkers to reduce the number of experiments required for detecting new ones. This is achieved by extracting the most representative genes in microarrays of HCC. RESULTS: In this work, we provide a method for extracting the differential expressed genes, up regulated ones, that can be considered candidate biomarkers in high throughput microarrays of HCC. We examine the power of several gene selection methods (such as Pearson's correlation coefficient, Cosine coefficient, Euclidean distance, Mutual information and Entropy with different estimators) in selecting informative genes. A biological interpretation of the highly ranked genes is done using KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, ENTREZ and DAVID (Database for Annotation, Visualization, and Integrated Discovery) databases. The top ten genes selected using Pearson's correlation coefficient and Cosine coefficient contained six genes that have been implicated in cancer (often multiple cancers) genesis in previous studies. A fewer number of genes were obtained by the other methods (4 genes using Mutual information, 3genes using Euclidean distance and only one gene using Entropy). A better result was obtained by the utilization of a hybrid approach based on intersecting the highly ranked genes in the output of all investigated methods. This hybrid combination yielded seven genes (2 genes for HCC and 5 genes in different types of cancer) in the top ten genes of the list of intersected genes. CONCLUSIONS: To strengthen the effectiveness of the univariate selection methods, we propose a hybrid approach by intersecting several of these methods in a cascaded manner. This approach surpasses all of univariate selection methods when used individually according to biological interpretation and the examination of gene expression signal profiles. 相似文献
707.
Essamadi AK Bengoumi M Zaoui D Faye B Bellenchi GC Musci G Calabrese L 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2002,131(3):509-517
Adult and young camel ceruloplasmin (Cp) were isolated and purified using the single-step chromatography on amino ethyl-activated sepharose. There are no differences between the adult and the young camel protein. The molecular mass of the protein, as estimated by SDS-PAGE (denaturant conditions), was approximately 130000 Da. The electrophoretic mobility of camel Cp is slightly higher as compared to human and sheep protein suggesting that the camel Cp is homogeneous, compact and more acid. The copper content was estimated to be 5.8+/-0.3 atoms per molecule. The spectroscopic feature includes an absorption maximum at 610 nm, which could be attributed to type 1 copper. The EPR spectrum was completely devoid of any typical signal of the type 2 copper. The kinetic parameters of the adult camel Cp for the specific activity as p-phenylendiamine oxidase were determined as K(m)=0.42 mM and V(max)=0.93 microM NADH/mn/mg Cp. The optimum pH for the activity was 5.7. 相似文献
708.
Xiuzu Song Nicole Mosby Jennifer Yang Aie Xu Zalfa Abdel‐Malek Ana Luisa Kadekaro 《Pigment cell & melanoma research》2009,22(6):809-818
Exposure of cultured human melanocytes to ultraviolet radiation (UV) results in DNA damage. In melanoma, UV‐signature mutations resulting from unrepaired photoproducts are rare, suggesting the possible involvement of oxidative DNA damage in melanocyte malignant transformation. Here we present data demonstrating immediate dose‐dependent generation of hydrogen peroxide in UV‐irradiated melanocytes, which correlated directly with a decrease in catalase activity. Pretreatment of melanocytes with α‐melanocortin (α‐MSH) reduced the UV‐induced generation of 7,8‐dihydro‐8‐oxyguanine (8‐oxodG), a major form of oxidative DNA damage. Pretreatment with α‐MSH also increased the protein levels of catalase and ferritin. The effect of α‐MSH on 8‐oxodG induction was mediated by activation of the melanocortin 1 receptor (MC1R), as it was absent in melanocytes expressing loss‐of‐function MC1R, and blocked by concomitant treatment with an analog of agouti signaling protein (ASIP), ASIP‐YY. This study provides unequivocal evidence for induction of oxidative DNA damage by UV in human melanocytes and reduction of this damage by α‐MSH. Our data unravel some mechanisms by which α‐MSH protects melanocytes from oxidative DNA damage, which partially explain the strong association of loss‐of‐function MC1R with melanoma. 相似文献
709.
The effect of ruthenium on the performance of porphyrin dye and porphyrin–fullerene (PF) dyad solar cells is investigated by using density functional theory and time-dependant density functional theory calculations. The results reveal that ruthenium facilitates rapid electron injection from porphyrin to fullerene, narrows the band gaps of porphyrin dye and PF dyad and alters the density of states near the corresponding Fermi levels. The HOMOs are localised on the donor moieties and the LUMOs on the acceptor moieties. The donor and acceptor dyads form good donor–acceptor pairs for photo-to-current conversion under the effect of ruthenium. HOMOs of porphyrin and ruthenium metalloporphyrin dyes fall within the (TiO2)60 and Ti38O76 gaps, and support the issue of typical interfacial electron transfer reaction. The calculated transition energies of porphyrin are almost insensitive to ethanol solvent effects. The introduction of ruthenium to the porphyrin ring leads to more active nonlinear optical performance, stronger response to the external electric field and induces higher photo-to-current conversion efficiency. Moreover, ruthenium shifts the absorption bands of porphyrin and makes it a potential candidate for harvesting light for photovoltaic applications. 相似文献
710.
Fleury M Charron DF Holt JD Allen OB Maarouf AR 《International journal of biometeorology》2006,50(6):385-391
The incidence of enteric infections in the Canadian population varies seasonally, and may be expected to be change in response to global climate changes. To better understand any potential impact of warmer temperature on enteric infections in Canada, we investigated the relationship between ambient temperature and weekly reports of confirmed cases of three pathogens in Canada: Salmonella, pathogenic Escherichia coli and Campylobacter, between 1992 and 2000 in two Canadian provinces. We used generalized linear models (GLMs) and generalized additive models (GAMs) to estimate the effect of seasonal adjustments on the estimated models. We found a strong non-linear association between ambient temperature and the occurrence of all three enteric pathogens in Alberta, Canada, and of Campylobacter in Newfoundland-Labrador. Threshold models were used to quantify the relationship of disease and temperature with thresholds chosen from 0 to −10°C depending on the pathogen modeled. For Alberta, the log relative risk of Salmonella weekly case counts increased by 1.2%, Campylobacter weekly case counts increased by 2.2%, and E. coli weekly case counts increased by 6.0% for every degree increase in weekly mean temperature. For Newfoundland-Labrador the log relative risk increased by 4.5% for Campylobacter for every degree increase in weekly mean temperature. 相似文献