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51.
Summary The apolipoprotein B gene is subject to mutations that may be important in coronary heart diseases. We have used polymerase chain reaction and denaturin gradient gel electrophoresis to characterize a single nucleotide substitution in the apolipoprotein B gene. This mutation affects amino acid 4311 of the protein and converts asparagine to serine. It was found in 24% of the 81 unrelated individuals analyzed. Moreover, another mutation was detected by sequencing in a single individual.  相似文献   
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53.
The network of interactions between human myelopoietic growth factors can lead to signal amplification that all regulate normal myelopoiesis. The present study identified synergistic interactions between recombinant human interleukin-3, GM-CSF and G-CSF on normal human marrow day 14 CFU-GM suggesting that the interactions between these human myelopoietic growth factors are mainly confined to the early stages of normal human myelopoiesis. The synergistic combinations of recombinant human interleukin-3 plus G-CSF and GM-CSF plus G-CSF warrant clinical trial for the recovery from cancer chemotherapy or radiotherapy-induced myelosuppression and for augmenting human defence against infections.  相似文献   
54.
In this study we determined that Aspergillus tamarii Kita is able to utilize Avena sativa L. (oats) for the production of β-xylosidase under static or shaking conditions in submerged liquid-state (LSF), solid-state (SSF) and slurry-state (SlSF) cultures. The produced enzyme was purified and characterized. Maximum yield occurred under shaking conditions in SSF cultures (33.7 U/ml), with 24.9 and 5.5 U/ml produced in SISF and LSF cultures, respectively. Peptone was found to be the best nitrogen additive and enhanced enzyme production (41.5 U/ml). The produced enzyme was precipitated by ammonium sulfate (60 %) and further purified by gel filtration through a Sephadex G-100 and ion exchange column of diethylaminoethyl cellulose, with a yield of 40.57 % and 35.73-fold purification. Enzyme activity was optimal at pH 5.5 and 55 °C. The purified enzyme retained full activity even at the end of a 1-h incubation at this optimal condition. Midpoint of thermal inactivation (Tm) was recorded at 60 °C after 90 min of exposure. The Michaelis–Menten constant, maximal reaction velocity, turnover number and specificity constant of the purified enzyme were calculated to be 0.075 mg/ml, 71.42 U/mg of protein, 7.14/S and 95.2 mg/ml/s, respectively. The inability of the purified enzyme to hydrolyze celluloses indicated that the enzyme was a free cellulase. The most efficient enzyme activators were Mg2+, followed by Mn2+ and Zn2+ in that order. The molecular mass of the purified enzyme was 91 kDa as determined by SDS-PAGE. The possibility of using the fermentation of ground oat hydrolysate for the production of ethanol and xylitol in the presence of Pichia stipitis Pignal was assessed. The maximum production of ethanol and xylitol were obtained after 72 h of fermentation, resulting in 11.06 and 21.51 g/l respectively.  相似文献   
55.
Journal of Molecular Histology - Breast cancer is the leading cancer worldwide among women. Traditional clinicopathological prognostic and predictive markers need refining to improve clinical...  相似文献   
56.
Molecular Biology Reports - Nuclear factor-κB (NF-κB) has been identified as the major link between inflammation and cancer. Natural agents that inhibit this pathway are essential in...  相似文献   
57.
This present study includes twelve species that represent the Ficus genus, namely; aspera, carica, tinctoria subsp. gibbosa, hirta, hispida, neriifolia, palmata, pumila, racemosa, septica, sur, and sycomorus, belonging to the Moraceae family. The species samples were collected from various locations in Egypt. The study focused on the anatomical and molecular characteristics of mature foliage leaves. Since the identification and classification of taxa are highly dependent on the anatomical features of leaves, the anatomical characteristics were recorded in the form of a comparison between the examined plants in the data matrix. This study aims to contribute to the identification of the studied species based on the anatomical details of the matured leaves. Anatomical characterization includes the variations in upper and lower epidermal layers that are covered by a thin or thick cuticle; the number of palisade and spongy layers; crystals; secretory elements; lithocysts; the midrib zone has parenchyma associated with mechanical tissue, vascular system, and investigation of trichomes; on the other hand, in the current study, the phylogenetic analysis was conducted by using the ITS and 5.8 S sequences. From the analysis of all the available data, it could be stated that there is an overall agreement with the anatomical character dendrogram.  相似文献   
58.
Hybrid rice has contributed significantly to the dramatic increase of rice production in the world. Despite this, little attention has been given to studying the genetic basis of heterosis in rice. In this paper, we report a diallel analysis of heterosis using two classes of molecular markers: restriction fragment length polymorphisms, (RFLPs) and microsatellites. Eight lines, which represent a significant portion of hybrid rice germ plasm, were crossed in all possible pairs, and the F1s were evaluated for yield and yield component traits in a replicated field trial. The parental lines were surveyed for polymorphisms with 117 RFLP probes and ten microsatellites, resulting in a total of 76 polymorphic markers well-spaced in the rice RFLP map. The results indicated that high level heterosis is common among these crosses: more than 100% midparent and 40% better-parent heterosis were observed in many F1s, including some crosses between maintainer lines. Heterosis was found to be much higher for yield than for yield component traits, which fits a multiplicative model almost perfectly. Between 16 and 30 marker loci (positive markers) detected highly significant effects on yield or its component traits. Heterozygosity was significantly correlated with several attributes of performance and heterosis. Correlations based on positive markers (specific heterozygosity) were large for midparent heterosis of yield and seeds/panicle and also for F1 kernel weight. These large correlations may have practical utility for predicting heterosis.  相似文献   
59.
Changes in the sucrose metabolism of Curcuma longa L. plants were studied under treatment with different triazole compounds viz., triadimefon (TDM) and propiconazole (PCZ). Plants were treated with TDM at 15 mg/L and PCZ at 10 mg/L separately by soil drenching on 80, 110, and 140 days after planting (DAP). The plants were harvested randomly on 90, 120, and 150 DAP to determine the effect of both the triazoles on sucrose metabolizing enzymes and phenol content. The sucrose metabolism was studied by analyzing sucrose metabolizing enzymes like sucrose synthase and sucrose phosphate synthase. All the analyses were assayed in leaves and tubers of both control and treated plants. It was found that both of the triazole compounds had profound effects on these parameters.  相似文献   
60.
Two new series of 2H-1-benzopyran-2-one derivatives substituted at C-6 and/or C-7 with propanolamines, and/or piperazine propanol derivatives have been synthesized and assayed for the H(1)-histamine antagonist. Twelve of the 20 newly synthesized 4- substituted benzopyrones have shown potent antihistaminic H(1) activity. In addition, molecular modeling and docking of the tested compounds into high affinity histamine binding protein (HBP) and histamine N-methyltranseferase (HNMT) active site in complex with its bound inhibitor (diphenhydramine) was performed in order to predict the affinity and orientation of these compounds at the active sites. The ICM score values show good agreement with predicted binding affinities obtained by molecular docking studies as verified by pharmacological screening. The results showed similar orientation of the target compounds at HBP, and HNMT active sites compared with reported histamine H(1) antagonist. Also, it was concluded that in order for the compounds to be active, they must bind with both active sites of HNMT enzyme (two pockets) to inhibit it. Compounds 8c, 8i, 11g, 11i, and 11k; observe the maximum activities.  相似文献   
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