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131.
Dorota Łażewska Kamil Kuder Xavier Ligneau Jean-Claude Camelin Walter Schunack Holger Stark Katarzyna Kieć-Kononowicz 《Bioorganic & medicinal chemistry》2009,17(8):3037-3042
Synthesis and biological activities of a series of homo- or substituted piperidine unsymmetrical diethers are described. The novel compounds were evaluated for histamine H3 receptor binding affinities at recombinant human H3 receptor stably expressed in HEK-293 cells. All diethers showed in vitro affinities in nanomolar concentration range. The most potent compounds are 1-[3-(3-(4-chlorophenoxy)propoxy)propyl]-3-methylpiperidine 11 (Ki = 3.2 nM) and 1-[3-(3-(4-chlorophenoxy)propoxy)propyl]azepane 13 (Ki = 3.5 nM). 相似文献
132.
Katarzyna Gach Janusz Szemraj Anna Wyrębska Anna Janecka 《Molecular biology reports》2011,38(2):1231-1236
Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in degradation of extracellular matrix, a process that initiates
uncontrolled spread of proliferating cancer cells and therefore plays a crucial role in cancer invasion and metastasis. Compounds
able to modulate MMP activity may become important tools in cancer research. In the present study we examined the effect of
two μ-selective opioids, morphine and endomorphin-2 (EM-2) on the production of MMP-2 and MMP-9 in MCF-7 cells. We report
that both opioids time- and concentration-dependently inhibited the expression and secretion of these MMPs. The observed effect
was not reversed by naloxone (Nal). Further experiments showed that morphine and EM-2 decreased endothelial nitric oxide synthase
(eNOS) mRNA level and nitric oxide (NO) secretion in MCF-7 cells. These findings indicate that attenuation of MMP secretion
by opioids was not mediated by opioid receptors but was under the control of nitric oxide system. 相似文献
133.
Troutman JM Chehade KA Kiegiel K Andres DA Spielmann HP 《Bioorganic & medicinal chemistry letters》2004,14(19):4979-4982
Three isoprenoid diphosphate analogues of farnesyl diphosphate (FPP) where the diphosphate has been replaced by methylene diphosphonate and the negative charges masked by frangible pivaloyloxymethyl (POM) esters were prepared. Farnesyl methylenediphosphonate is a sub-micromolar substrate for protein farnesyl transferase. The tripivaloyloxymethyl esters of isoprenoid methylenediphosphonate have significantly increased lipophilicity and may act as important farnesyl diphosphate prodrugs. 相似文献
134.
Dolińska B Zieliński M Dobrzański Z Chojnacka K Opaliński S Ryszka F 《Biological trace element research》2012,147(1-3):354-358
The influence of incubation conditions, enzyme type, hydrolysis time, and potassium iodide concentration on hydrolysis and iodine enrichment were studied in supernatant and pellets of Saccharomyces cervisiae hydrolysates. The type of enzyme used and incubation time significantly influence hydrolysis efficiency and protein concentration in supernatant and pellet. The highest protein hydrolysis efficiency was obtained by 24-h incubation with papain. Significantly lower values were observed for pepsin and autolysis. The potassium iodide concentration influences the iodine content of supernatant and pellet, but not hydrolysis. Iodide enrichment of supernatant and pellet depends on the concentration of iodide using during incubation. High concentration of iodide and long incubation times were the conditions for optimal iodide enrichment and high-protein hydrolysates. The optimal hydrolysis efficiency and iodine enrichment were obtained during 24-h incubation with papain in a 4.5-mM potassium iodide medium. The efficiency reached 98.22% with iodine concentrations of 2,664.91 and 9,200.67 μg/g iodine in pellet and supernatant, respectively. 相似文献
135.
Tomasz Kowalczyk Katarzyna Hnatuszko-Konka Aneta Gerszberg Andrzej K. Kononowicz 《World journal of microbiology & biotechnology》2014,30(8):2141-2152
Elastin-like polypeptides (ELP) are artificial, genetically encodable biopolymers, belonging to elastomeric proteins, which are widespread in a wide range of living organisms. They are composed of a repeating pentapeptide sequence Val–Pro–Gly–Xaa–Gly, where the guest residue (Xaa) can be any naturally occurring amino acid except proline. These polymers undergo reversible phase transition that can be triggered by various environmental stimuli, such as temperature, pH or ionic strength. This behavior depends greatly on the molecular weight, concentration of ELP in the solution and composition of the amino acids constituting ELPs. At a temperature below the inverse transition temperature (Tt), ELPs are soluble, but insoluble when the temperature exceeds Tt. Furthermore, this feature is retained even when ELP is fused to the protein of interest. These unique properties make ELP very useful for a wide variety of biomedical applications (e.g. protein purification, drug delivery etc.) and it can be expected that smart biopolymers will play a significant role in the development of most new materials and technologies. Here we present the structure and properties of thermally responsive elastin-like polypeptides with a particular emphasis on biomedical and biotechnological application. 相似文献
136.
Witold Kycler Bronisława Szarzyńska Cezary Łoziński Konstanty Korski Katarzyna Lamperska 《Reports of Practical Oncology and Radiotherapy》2012,17(1):13-18
Background/aimThe aim of our study was to check how MGMT methylation status together with known factors influenced the risk of colon cancer development.Materials and methodsWe examined patients with colon polyps. Information concerning gender, age, lifestyle, diet, anthropometry and medical information, including cancer and family history of cancer, was analyzed. Polymorphism variety of MGMT gene was investigated in another study. Genetic analysis for MGMT methylation assessment was performed for polyp tissue samples from 143 patients.ResultsPositive methylation MGMT status was found in 55 patients. There was no correlation between gender and MGMT methylation status (p = 0.43). We did not find correlation between patients younger and older than 60 (p = 0.87). There was no correlation between smoking and MGMT methylation status (p = 0.36). We did not find correlation between BMI and MGMT methylation status (p = 0.86). We did not find correlation between MGMT methylation status and colon cancer in familial history (p = 0.45).ConclusionOur study showed no correlations between methylation status of MGMT polymorphisms and clinical features like age, gender, polyp localization, smoking status, or obesity. It has been shown previously that MGMT methylation status may show nonspecific methylation in colon polyps. Gene methylation status in adenoma tissues has also been associated by other authors with the adenoma's size, histology, and degree of atypia. In our study, we evaluated the gene methylation status in colon polyps and found no association with adenoma characteristics. The present study showed no correlation for MGMT methylation in polyps in different regions of colon. 相似文献
137.
Molecular chaperones recognize and bind destabilized proteins. This can be especially important for proteins whose stability
is reduced by mutations. We focused our study on a major chaperone system, RAC-Ssb, which assists folding of newly synthesized
polypeptides in the yeast cytosol. A sensitive phenotypic assay, the red color of Ade2 mutants, was used to screen for variants
with metabolic activity dependent on RAC-Ssb. None of the Ade2 mutants were found to exhibit lower metabolic activity after
inactivation of RAC-Ssb. In order to explicitly test the relationship between protein instability and activity of chaperones,
a series of temperature sensitive Ade2 mutants were tested in the presence or absence of RAC-Ssb. The growth of Ade2(ts) mutants
at elevated temperatures was enhanced if chaperones were missing. Similar pattern was found for thermally sensitive mutants
of several other genes. Because RAC-Ssb normally supports the folding of proteins, it appears paradoxical that catabolic activity
of mutants is reduced when these chaperones are present. We suggest that under non-stressful conditions, molecular chaperones
are tuned to support folding of native proteins, but not that of mutated ones. 相似文献
138.
Wysocka M Lesner A Guzow K Mackiewicz L Legowska A Wiczk W Rolka K 《Analytical biochemistry》2008,378(2):208-215
In this study, chemical synthesis of the selective chromogenic/fluorogenic substrates for proteinase 3 is described. The substrates’ sequence was obtained using combinatorial chemistry methods. Deconvolution of the tripeptide library against proteinase 3 with general formula ABZ-X3-X2-X1-ANB-NH2 yielded the active sequence. Selected peptide was further modified on its C terminus to investigate the impact of chromophore moiety modification on enzyme-substrate interaction. To determine specificity, activity of selected substrates was characterized against proteinase 3 and neutrophil elastase. Finally, the peptide ABZ-Tyr-Tyr-Abu-ANB-NH2 displayed the highest value of specificity constant (kcat/KM = 189 × 103 M−1 s−1) for proteinase 3. To the best of our knowledge, this is the first short peptide that undergoes selective proteolysis by proteinase 3 and displays no significant hydrolysis in the presence of human neutrophil elastase and cathepsin G. 相似文献
139.
140.
Tadeusz Osadnik Joanna Katarzyna Strzelczyk Rafa? Regu?a Kamil Bujak Martyna Fronczek Ma?gorzata Gonera Marcin Gawlita Jaros?aw Wasilewski Andrzej Lekston Anna Kurek Marek Gierlotka Przemys?aw Trzeciak Micha? Hawranek Zofia Ostrowska Andrzej Wiczkowski Lech Poloński Mariusz G?sior 《PloS one》2016,11(3)