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El Husseiny NM Said ES El Shahat Mohamed N Othman AI 《Biological trace element research》2011,143(3):1451-1460
The aim of this study was to confirm if there is a link between the alteration in blood levels of trace elements (chromium,
copper, lead, cadmium, and zinc) and dehydroepiandrosterone sulfate (DHEAS) in healthy and diabetic states. This study is
the first study to test these parameters in Egyptians. The study included 150 subjects divided into the following four groups:
healthy middle-aged, healthy elderly, middle-aged diabetics, and elderly diabetics. Our results revealed a statistically significant
decrease in the level of DHEAS in the elderly compared to middle-aged healthy and diabetic groups (p < 0.05). There was a significant difference between the middle-aged groups with respect to zinc, copper, chromium, and cadmium
levels. Zinc and copper were lower in the diabetic subjects while chromium and cadmium were higher in the same group in comparison
to healthy subjects. In the elderly groups, there were significant increases in chromium and cadmium levels in diabetic subjects
rather than healthy ones. There was a significant increase in the thiobarbituric acid reactive substance level in the elderly
healthy and diabetic groups and a significant decrease in the glutathione level in the elderly groups. There was no correlation
between the levels of trace elements and DHEAS or between the levels of DHEAS, oxidants, and antioxidants in all of the tested
groups. In conclusion, only the DHEAS level was correlated with age. There was no difference between the diabetic and healthy
groups with respect to the levels of trace elements, with the exception of chromium and cadmium, which suggests the effect
of pollution on the pathogenesis of diabetes in Egyptians. No correlation existed between the levels of DHEAS and trace elements,
oxidants, and antioxidants. Finally, we believe that there is a large regional variation in the levels of trace elements due
to different environmental exposure and nutritional factors which are responsible for contradictory results regarding the
pathogenesis of diseases related to alterations in the levels of trace elements. 相似文献
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The effect of inorganic pollutants on the treatment of organic pollutants using algal/bacterial microcosm was investigated in a continuous photobioreactor. The microcosm was composed of Chlorella vulgaris MM1 and Pseudomonas MT1 and was able to efficiently treat artificial waste-water contaminated with 6.4 salicylate and 2.2 mM phenol at a hydraulic retention time of 4 days. No negative effect was recorded when the waste-water was supplemented with 1.6 mM thiocyanate; however, the treatment efficiency severely deteriorated when the system was challenged with 0.74 mM cyanide. Addition of 2 g NaHCO3 l?1 did not improve the efficiency of the treatment. Toxicity of the pollutants to the alga was cyanide > thiocyanate > phenol > salicylate. The high toxicity of the waste-water was eliminated either by a 25-fold dilution or by photocatalytic pre-treatment which allowed the subsequent efficient biological treatment. 相似文献
35.
Badary OA AbdEl-Gawad HM Taha RA Ali AA Hamada FM 《Journal of biochemical and molecular toxicology》2003,17(2):86-91
The effects of benzo[a]pyrene (B[a]P) on some drug-metabolizing and antioxidant systems in liver, lung, and stomach were investigated in normal and protein malnutrition (PM) rats. PM significantly inhibited tissue glutathione (GSH) content and increased hepatic lipid peroxidation. Cytochrome P450 isoform CYP1A1 was significantly increased in various tissues (42-73%). Also, lung glutathione S-transferase (GST) activity was significantly decreased (19%) in PM rats. On the other hand, B[a]P significantly induced tissue GSH of control and PM rats. Also, hepatic lipid peroxidation were significantly increased in control rats treated with B[a]P. Superoxide dismutase (SOD) activity was decreased by B[a]P treatment in PM rat stomach. B[a]P significantly induced both quinone reductase (QR) (in all tissues) and hepatic GST of control and PM rats. GST activity in PM rat liver was significantly higher than that of control rat liver after B[a]P treatment. Also, B[a]P induced hepatic CYP1A1 by 32-fold and 27-fold (P < or = 0.05) in control and PM rats, respectively. Stomach and hepatic UDP-glucuronosyltransferase activities were significantly decreased (34%) and increased (74%), respectively by B[a]P in PM rats. The results suggest that PM status has a modifying effect on the response of some antioxidant and metabolizing systems to a well-known carcinogen risk. 相似文献
36.
Hyperoxia induces retinal vascular endothelial cell apoptosis through formation of peroxynitrite 总被引:5,自引:0,他引:5
Gu X El-Remessy AB Brooks SE Al-Shabrawey M Tsai NT Caldwell RB 《American journal of physiology. Cell physiology》2003,285(3):C546-C554
Hyperoxia exposure induces capillary endothelial cell apoptosis in the developing retina, leading to vaso-obliteration followed by proliferative retinopathy. Previous in vivo studies have shown that endothelial nitric oxide synthase (NOS3) and peroxynitrite are important mediators of the vaso-obliteration. Now we have investigated the relationship between hyperoxia, NOS3, peroxynitrite, and endothelial cell apoptosis by in vitro experiments using bovine retinal endothelial cells (BREC). We found that BREC exposed to 40% oxygen (hyperoxia) for 48 h underwent apoptosis associated with activation of caspase-3 and cleavage of the caspase substrate poly(ADP-ribose) polymerase. Hyperoxia-induced apoptosis was associated with increased formation of nitric oxide, peroxynitrite, and superoxide anion and was blocked by treatment with uric acid, nitro-L-arginine methyl ester, or superoxide dismutase. Analyses of the phosphatidylinositol 3-kinase/Akt kinase survival pathway in cells directly treated with peroxynitrite revealed inhibition of VEGF- and basic FGF-induced activation of Akt kinase. These results suggest that hyperoxia-induced formation of peroxynitrite induces BREC apoptosis by crippling key survival pathways and that blocking peroxynitrite formation prevents apoptosis. These data may have important clinical implications for infants at risk of retinopathy of prematurity. oxygen-induced retinopathy; vaso-obliteration; superoxide; nitric oxide 相似文献
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Maria Pérez-Marcos Maria Isabel Arnaldos Elena López-Gallego Aurelio Luna Azza Khedre Maria Dolores García 《法国昆虫学会纪事》2018,54(4):367-380
Summary. Since the entomosarcosaprophagous community is affected by environmental variables, it needs to be studied under different environmental conditions. In addition, because most studies are usually conducted with biomodels rather than human corpses, it is necessary to verify whether or not the type of decomposing animal matter affects the decomposition process itself, as well as the related fauna. For this reason, a study was conducted on the sarcosaprophagous Diptera community in two different environments of the Region of Murcia (SE Spain), using piglet and chicken carcasses, and Schoenly traps as collecting devices. To analyse possible differences regarding faunal composition among samples, a one-way Permutational Multivariate Analysis of Variance (PERMANOVA) was applied. The results indicate significant differences concerning the bait. In this sense, Calliphoridae, Muscidae, Fanniidae and Sarcophagidae families are the main groups responsible for such differences. In terms of environment-related differences, the only species that contribute are those of the dominant families, Calliphoridae and Muscidae. 相似文献
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40.
Prophylactic administration of carnosine and melatonin abates the incidence of renal toxicity induced by an over dose of titanium dioxide nanoparticles 下载免费PDF全文
Laila Mohamed Fadda Azza M. Mohamed Hanaa Mahmoud Ali Hanan Hagar Manal Aldossari 《Journal of biochemical and molecular toxicology》2018,32(3)
The alleviative effects of two antioxidants, carnosine (Car) and melatonin (Mel), against titanium dioxide nanoparticles (TiO2‐NPs) toxicity‐induced oxidative and inflammatory renal damage were examined in rats. Administration of these antioxidants along with TiO2‐NPs effectively reduced serum urea, uric acid, creatinine, glucose, tumor necrosis factor‐α, interleukin‐6, C‐reactive protein, immunoglobulin G, vascular endothelial growth factor, and nitric oxide, as well as a significant amelioration of the decrease in glutathione levels in renal tissue was observed, compared to those in rats treated with TiO2‐NPs alone. The renoprotective properties of the antioxidants were confirmed by reduced intensity of renal damage as demonstrated by histological findings. In conclusion, Car and Mel play protective roles against TiO2‐NPs‐induced renal inflammation and oxidative injury, likely due to their antioxidant and anti‐inflammatory properties. 相似文献