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71.
Probiotics and Antimicrobial Proteins - Data on the effects of synbiotic supplementation on glycemic control, lipid profiles, and atherogenic index of plasma (AIP) of women with polycystic ovary...  相似文献   
72.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common inherited disease, which causes neonatal hemolytic anemia and jaundice. Recent studies of our group showed that the Mediterranean variant of this enzyme (Gd-Md) is the predominant G6PD in Iranian male infants suffering from jaundice; this variant is classified as severe G6PD deficiency. Considering the importance of G6PD reaction and its products NADPH and glutathione (GSH) against oxidative stress, we hypothesized the failure of detoxification of H(2)O(2) in G6PD-deficient white blood cells that could probably induce primary DNA damage. For the evaluation of DNA damage, we analyzed mononuclear leukocytes of 36 males suffering from the Gd-Md deficiency using alkaline single cell gel electrophoresis (SCGE) or comet assay. The level of DNA damage was compared with the level of basal DNA damage in control group represented by healthy male infant donors (of the same age group). Visual scoring was used for the evaluation of DNA damages. The results showed that the mean level of the DNA strand breakage in mononuclear leukocytes of 36 male G6PD-deficient (Gd-Md) infants was significantly higher (P < 0.001) than those observed in the normal lymphocytes. In conclusion, this investigation indicates that the mononuclear leukocytes of the Gd-Md samples may be exposed to DNA damage due to oxidative stress. This is the first report using comet assay for evaluation of DNA damage in severe G6PD deficiency samples.  相似文献   
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As effector innate immune cells and as a host to the protozoan parasite Leishmania, macrophages play a dual role in antileishmanial immunoregulation. The 2 key players in this immunoregulation are the macrophage-expressed microRNAs (miRNAs) and the macrophage-secreted cytokines. miRNAs, as small noncoding RNAs, play vital roles in macrophage functions including cytokines and chemokines production. In the reverse direction, Leishmania-regulated cytokines alter miRNAs expression to regulate the antileishmanial functions of macrophages. The miRNA patterns vary with the time and stage of infection. The cytokine-regulated macrophage miRNAs not only help parasite elimination or persistence but also regulate cytokine production from macrophages. Based on these observations, we propose a novel immunoregulatory framework as a scientific rationale for antileishmanial therapy.  相似文献   
75.
β-Thalassemia is the most common single gene disorder in Iran and more than 25,000 affected individuals have been reported. It has been reported that in patients with β-thalassemia in the presence of Xmn1 polymorphic site the level of Hb F and Gγ: Aγ ratio is increased. The prevalence of Xmn1 polymorphic site, Gγ: Aγ ratio and Hb F in 197 β-thalassemia major patients from the Kermanshah Province of Iran were studied. The Xmn1 polymorphic site was determined by PCR-RFLP procedure. The levels of Gγ and Aγ chains were detected by HPLC. The percent of Hb F was determined using electrophoresis method. In β-thalassemia major patients the frequency of presence Xmn1 was 0.39. The mean of Gγ: Aγ ratio was found to be 2.5. In the present study it was found that in the presence of Xmn1 polymorphic site Gγ percent and Gγ: Aγ ratio were significantly increased (P = 0.01) and the clinical features such as splenomegaly and bone marrow expansion were significantly improved (P = 0.01). We found that in the presence of Xmn1 polymorphic site on both chromosomes (+/+) the level of Hb F tended to be increased compared to the absence of Xmn1 (−/−). The present investigation has studied the frequency of Xmn1 polymorphic site in β-thalassemia major patients from Western Iran and has revealed that the presence of this polymorphic site caused a positive influence on Hb F production and the Gγ percent which could improve the clinical symptoms of β-thalassemia patients.  相似文献   
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Oxygen mass transfer was studied in conventional, bead mill and baffled roller bioreactors. Using central composite rotational design, impacts of size, rotation speed and working volume on the oxygen mass transfer were evaluated. Baffled roller bioreactor outperformed its conventional and bead mill counterparts, with the highest k L a obtained in these configurations being 0.58, 0.19, 0.41 min?1, respectively. Performances of the bead mill and baffled roller bioreactor were only comparable when a high bead loading (40 %) was applied. Regardless of configuration increase in rotation speed and decrease in working volume improved the oxygen mass transfer rate. Increase in size led to enhanced mass transfer and higher k L a in baffled roller bioreactor (0.49 min?1 for 2.2 L and 1.31 min?1 for 55 L bioreactors). Finally, the experimentally determined k L a in the baffled roller bioreactors of different sizes fit reasonably well to an empirical correlation describing the k L a in terms of dimensionless numbers.  相似文献   
78.
Endometriosis is a frequent and chronic illness in young women which could be defined by the existence of endometrial stroma and glands outside of the normal site of the lining of the uterus. It has painful symptoms. The advanced stage of endometriosis may lead to gynecological malignancies, such as ovarian cancer, and other complications, including infertility. However, its exact physiopathology is not well known. Recent studies have shown the possible roles of inflammation along with oxidative stress. Additionally, angiogenesis and apoptosis dysregulation contribute to endometriosis pathophysiology. Therapeutic strategies and continuing attempts, to conquer endometriosis should be done regarding molecular signaling pathways. Thus, the present review summarizes current studies and focuses on molecular mechanisms.  相似文献   
79.
After a dry period with prolonged droughts in the 1970s and 1980s, recent scientific outcome suggests that the decades of abnormally dry conditions in the Sahel have been reversed by positive anomalies in rainfall. Various remote sensing studies observed a positive trend in vegetation greenness over the last decades which is known as the re‐greening of the Sahel. However, little investment has been made in including long‐term ground‐based data collections to evaluate and better understand the biophysical mechanisms behind these findings. Thus, deductions on a possible increment in biomass remain speculative. Our aim is to bridge these gaps and give specifics on the biophysical background factors of the re‐greening Sahel. Therefore, a trend analysis was applied on long time series (1987–2013) of satellite‐based vegetation and rainfall data, as well as on ground‐observations of leaf biomass of woody species, herb biomass, and woody species abundance in different ecosystems located in the Sahel zone of Senegal. We found that the positive trend observed in satellite vegetation time series (+36%) is caused by an increment of in situ measured biomass (+34%), which is highly controlled by precipitation (+40%). Whereas herb biomass shows large inter‐annual fluctuations rather than a clear trend, leaf biomass of woody species has doubled within 27 years (+103%). This increase in woody biomass did not reflect on biodiversity with 11 of 16 woody species declining in abundance over the period. We conclude that the observed greening in the Senegalese Sahel is primarily related to an increasing tree cover that caused satellite‐driven vegetation indices to increase with rainfall reversal.  相似文献   
80.
Hydrogen production by water splitting may be an appealing solution for future energy needs. To evolve hydrogen efficiently in a sustainable manner, it is necessary first to synthesize what we may call a 'super catalyst' for water oxidation, which is the more challenging half reaction of water splitting. An efficient system for water oxidation exists in the water oxidizing complex in cyanobacteria, algae and plants; further, recently published data on the Manganese-calcium cluster have provided details on the mechanism and structure of the water oxidizing complex. Here, we have briefly reviewed the characteristics of the natural system from the standpoint of what we could learn from it to produce an efficient artificial system. In short, to design an efficient water oxidizing complex for artificial photosynthesis, we must learn and use wisely the knowledge about water oxidation and the water oxidizing complex in the natural system. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial.  相似文献   
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