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51.
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Although endothelial dysfunction deteriorates diabetic angiopathy, the mechanisms are obscure. We revealed that high glucose augmented eNOS through stimulation of eNOS mRNA in cultured BAECs. NO was decreased and O2- was increased simultaneously. NOS inhibitor, inhibited O2- release, so did NADPH oxidase inhibitor. The effects were synergistic. Both intracellular BH4 level and GTPCH1 activity were decreased by high glucose, in line with decrease of GTPCH1 mRNA. HMG-CoA reductase inhibitor, atorvastatin increased GTPCH1 mRNA and activity, and BH4 level. Conclusively, high glucose leads to eNOS dysfunction by inhibiting BH4 synthesis and atorvastatin stimulate BH4 synthesis directly, and it may work as atherogenic process.  相似文献   
53.
We propose a simple procedure for the identification and quantitative analysis of neurite outgrowth in neuronal cell lines that were uniformly differentiated. Upon stimulation most neuronal cell lines extend neurites in the differentiation process, resulting, according to our observation, in the increase of cell surface area. This increase is dependent on the length and the number of extended neurites. Furthermore, we use this method for the phenotype analysis of cell array experiments to perform large-scale functional evaluation of genes involved in the neurite outgrowth during neuronal differentiation.  相似文献   
54.
To establish an in vitro method of predicting in vivo efficacy of antifungal drugs against Candida albicans and Aspergillus fumigatus, the antifungal activities of fluconazole, itraconazole, and amphotericin B were determined in mouse serum. The minimum inhibitory concentration (MIC) of each drug was measured using mouse serum as a diluent. For C. albicans, the assay endpoint of azoles was defined as inhibition of mycelial extension (mMIC) and for A. fumigatus, as no growth (MIC). The MICs of amphotericin B for both pathogens were defined as the MIC at which no mycelial growth occurred. Serum MIC or mMIC determinations were then used to estimate the concentration of the drugs in serum of mice treated with antifungal drugs by multiplying the antifungal titer of the serum samples by the serum (m)MIC. The serum drug concentrations were also determined by HPLC. The serum concentrations estimated microbiologically showed good agreement with those determined by HPLC, except for itraconazole. Analysis of the serum samples from itraconazole-treated mice by a sensitive bioautography revealed the presence of additional spots, not seen in control samples of itraconazole. The bioautography assay demonstrated that the additional material detected in serum from mice treated with itraconazole was an active metabolite of itraconazole. The data showed that the apparent reduction in the itraconazole serum concentration as determined by HPLC was the result of the formation of an active metabolite, and that the use of a microbiological method to measure serum concentrations of drugs can provide a method for prediction of in vivo efficacy of antifungal drugs.  相似文献   
55.
Chlorogenic acid possessed a weak caffeine-like psychostimulant property when assessed for its effect on spontaneous locomotor activity in mice. In the evaluation of the effects for the major metabolites of chlorogenic acid which were detected upon incubation with rat feces and/or excreted in urine after oral administration to rats, caffeic and m-coumaric acids were found to be the principal active metabolites, while the others contributed little to this caffeine-like psychostimulant activity.  相似文献   
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The occurrence of the salp Thetys vagina was observed in theJapan Sea during spring 2004. Catches up to 187 kg wet weight(WW) per 2.18 x 105 m3 (equal to 0.9 g WW m–3) were collectedwith 10-m diameter surface-water otter trawl nets. The horizontaldistribution indicated that the high biomass was related tothe area with high chlorophyll a (Chl a) concentration, whichwas located around the subarctic front with the warm TsushimaCurrent. Five prey taxa were identified from the gut contentsof individuals from the high Chl a area. The diatom Coscinodiscusspp. (13–55 µm in diameter) dominated numerically.Another significant prey was the large diatom Coscinodiscuswailesii (219–313 µm) that is an indicator of thespring bloom in this area. The mass occurrence of T. vaginathus appears related to phytoplankton availability, though themechanisms remain uncertain.  相似文献   
58.
Estrogens are essential for normal reproductive activity in female and male vertebrates. In female reptiles, they are essential for ovarian differentiation during a critical developmental stage. To understand the molecular mechanisms of estrogen action in the Nile crocodile (Crocodylus niloticus), we have isolated cDNA encoding the estrogen receptor alpha (ERalpha) from the ovary. Degenerate PCR primers specific to ER were designed and used to amplify Nile crocodile cDNA from the ovary. The full-length Nile crocodile ERalpha cDNA was obtained using 5' and 3' rapid amplification cDNA ends (RACE). The deduced amino acid sequence of the Nile crocodile ERalpha showed high identity to the American alligator ERalpha (98%), caiman ER (98%), lizard ER (82%) and chicken ERalpha (92%), although phylogenetic analysis suggested profound differences in the rate of sequence evolution for vertebrate ER sequences. Expression of ERalpha was observed in the ovary and testis of juvenile Nile crocodiles. These data provide a novel tool allowing future studies examining the regulation and ontogenic expression of ERalpha in crocodiles and expands our knowledge of estrogen receptor evolution.  相似文献   
59.
The distribution of pink-pigmented facultative methylotrophs (PPFMs) on the leaves of various vegetables was studied. All kinds of vegetable leaves tested gave pink-pigmented colonies on agar plates containing methanol as sole carbon source. The numbers of PPFMs on the leaves, colony-forming units (CFU)/g of fresh leaves, differed among the plants, although they were planted and grown at the same farm. Commercial green perilla, Perilla frutescens viridis (Makino) Makino, gave the highest counts of PPFMs (2.0-4.1×10(7) CFU/g) of all the commercial vegetable leaves tested, amounting to 15% of total microbes on the leaves. The PPFMs isolated from seeds of two varieties of perilla, the red and green varieties, exhibited high sequence similarity as to the 16S rRNA gene to two different Methylobacterium species, M. fujisawaense DSM5686(T) and M. radiotolerans JCM2831(T) respectively, suggesting that there is specific interaction between perilla and the PPFMs.  相似文献   
60.
5-Alkenyl or 5-alkynyl-4-anilinopyrimidines were prepared and evaluated for in vitro inhibition of EGFR/Her-2 kinase activity and the growth of tumor cell lines (BT474 and N87). Several of these compounds inhibited the growth of BT474 and N87 at concentrations below 200nM. Structure-activity relationship studies revealed a critical role for the 5-alkynyl moieties. The representative compound 19 exhibited significant antitumor potency in a mouse xenograft model.  相似文献   
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