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21.
Myotonic dystrophy 1 (MD1) is caused by a CTG expansion in the 3′-unstranslated region of the myotonic dystrophy protein kinase (DMPK) gene. MD1 patients frequently present insulin resistance and increased visceral adiposity. We examined whether DMPK deficiency is a genetic risk factor for high-fat diet-induced adiposity and insulin resistance using the DMPK knockout mouse model. We found that high-fat fed DMPK knockout mice had significantly increased body weights, hypertrophic adipocytes and whole-body insulin resistance compared with wild-type mice. This nutrient-genome interaction should be considered by physicians given the cardiometabolic risks and sedentary lifestyle associated with MD1 patients.  相似文献   
22.

Background  

Coffea canephora, also called Robusta, belongs to the Rubiaceae, the fourth largest angiosperm family. This diploid species (2x = 2n = 22) has a fairly small genome size of ≈ 690 Mb and despite its extreme economic importance, particularly for developing countries, knowledge on the genome composition, structure and evolution remain very limited. Here, we report the 160 kb of the first C. canephora Bacterial Artificial Chromosome (BAC) clone ever sequenced and its fine analysis.  相似文献   
23.
The viability of two strains of Lentinula edodes and two of L. boryana under cryogenic storage during 1 week has been studied from the evaluation of five contact periods (1, 1.5, 2, 3 and 5 h) of the cryoprotector, glycerol 10% (v/v), with the mycelium. On average, 99.25% of samples were recovered, 1.5 h being the best contact period. Afterwards, samples of the strains, before and after the cryogenic process, were cultivated at a pilot plant using a mix of Carpinus carolineana sawdust, rice bran and sorghum grains as substrate. The evaluation parameters were: days of incubation, primordia initiation, number of flushes, fruiting body sizes and biological efficiency (EB). Only L. edodes developed carpophores. On average, 3–4 flushes were obtained, which reached EB of 67.1 ± 30.7 to 74.7 ± 24.5 with no statistical differences detected between the yields. The majority of fructification sizes ranged from 5 to 14.9 cm. Morphological differences between the samples before and after the treatment were not observed.  相似文献   
24.
Sleep deficit and related disorders are becoming increasingly prevalent in modern life and an extensive literature has documented that acute or chronic sleep deprivation can lead to several physiological consequences. Here, we evaluated the effects of sleep deprivation on hematopoietic composition of either bone marrow or peripheral blood. Mice were subjected to paradoxical sleep deprivation (PSD) for 72 h by modified multiple platform method, with or without an additional sleep recovery (SR) period of 10 days. PSD decreased total cellularity of the bone marrow and peripheral blood concomitantly. Subsequent analysis of cell composition showed that absolute number of hematopoietic stem/progenitor cells and colony-forming units was decreased. Moreover, the absolute number of granulocytes and monocytes in bone marrow was reduced in PSD group. These alterations were paralleled by an accumulation of neutrophils and monocytes in peripheral blood. PSD also induced lymphopenia in the circulation. To the best of our knowledge, this is the first study that demonstrates the importance of sleep on the hematopoietic microenvironment and provides new insights into the relationship between sleep and the immune system.  相似文献   
25.
26.
The objective of the present in vitro study was to estimate the adhesion strength of nanometer crystalline hydroxyapatite (HA)-small intestine sub-mucosa (SIS) composites on model implant surfaces. Techniques of thermal denaturation (60 degrees C, 20 min) of SIS were used to enhance the adhesion strength of entheses materials to underlying implants. Specifically, results indicated that the adhesion strength of thermally denatured SIS was 2-3 times higher than that for normal unheated SIS. In addition, aqua-sonicated, hydrothermally treated nano-HA dispersions enhanced the adhesion strength of SIS on implant surfaces. Importantly, results of the present study demonstrated that human skeletal muscle cell (hSkMC) numbers were not affected by thermally denaturing SIS in nano-HA composite coatings; however, they increased on aqua-sonicated nano-HA/SIS composites compared with SIS alone. Interestingly, thermally denatured SIS that contained aqua-sonicated, hydrothermally treated nano-HA decreased human osteoblasts (hOBs) numbers compared with respective unheated composites; all other composites when thermally denatured did not influence hOB numbers. Results also showed that the number of hOBs increased on nano-HA/SIS composites compared with SIS composites alone. Human mesenchymal stem cell (hMSC) numbers were not affected by the presence of nano-HA in SIS composites. For these reasons, the collective results of this in vitro study demonstrated a technique to increase the coating strength of entheses coatings on implant surfaces (using thermally denatured SIS and aqua-sonicated, hydrothermally prepared nano-HA) while, at the same time, supporting cell functions important for entheses regeneration.  相似文献   
27.
We have shown that the ameliorative effect of stannous chloride (SnCl2) pretreatment on potassium dichromate (K2Cr2O7)-induced renal damage 24 h after K2Cr2O7 injection was associated with the induction of heme oxygenase-1 (HO-1). In this work we evaluated: (a) if the protective effect of SnCl2 (given 12 h before K2Cr2O7) is associated with changes in the renal activity of HO-1, superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT) 24 and 48 h after K2Cr2O7 injection, and (b) if HO-1 induction is indispensable before K2Cr2O7 injection. It was found that the protective effect of SnCl2 on renal function was observed both at 24 and 48 h reaching its maximum at 24 h when HO-1 expression was higher. Cu,Zn-SOD, Mn-SOD, and GR activities remained unchanged whereas GPx and CAT activities decreased at 48 h in K2Cr2O7-treated rats. The activity of Cu,Zn-SOD, Mn-SOD, GPx, CAT, and GR was unchanged in the SnCl2-treated rats. To fulfill the objective (b) groups of rats treated with K2Cr2O7 and SnCl2 (given at the same time or 12 h after K2Cr2O7) were studied 24 h after K2Cr2O7-injection. The simultaneous injections of SnCl2 and K2Cr2O7 had no protective effect whereas the injection of SnCl2 12 h after K2Cr2O7 exacerbated renal damage. In conclusion, the protective effect of SnCl2 on K2Cr2O7-induced nephrotoxicity is associated with HO-1 induction and not with other antioxidant enzymes (Cu,Zn-SOD, Mn-SOD, GPx, GR, and CAT) and SnCl2 has a preventive and not a therapeutic effect on renal damage induced by K2Cr2O7.  相似文献   
28.
Gentamicin (GM) is an antibiotic whose clinical use is limited by its nephrotoxicity. Experimental evidences suggest a role of reactive oxygen species in GM-induced nephrotoxicity. Therefore, we investigated if aged garlic extract (AGE), an antioxidant, has a protective role in this experimental model. Four groups of male Wistar rats were studied: 1) Control (CT), injected subcutaneously (s.c.) and intraperitoneally (i.p.) with saline, 2) GM, treated s.c. with GM (70 mg/kg/12 hours/4 days), 3) AGE, treated i.p with AGE (1.2 mL/kg/12 hours/6 days), and 4) GM + AGE treated with GM and AGE. The treatment with AGE started two days before the first dose of GM (GM + AGE group) or saline (AGE group). Animals were sacrificed on day 5, and blood, urine, and kidneys were obtained. Nephrotoxicity was made evident by: 1) the increase in blood urea nitrogen and plasma creatinine, 2) the decrease in plasma glutathione peroxidase (GPx) activity and the urinary increase in N-acetyl-beta-D-glucosaminidase activity and total protein, and 3) necrosis of proximal tubular cells. These alterations were prevented or ameliorated by AGE treatment. Furthermore, AGE prevented the GM-induced increase in the renal levels of oxidative stress markers: nitrotyrosine and protein carbonyl groups and the decrease in manganese superoxide dismutase (Mn-SOD), GPx, and glutathione reductase (GR) activities. The protective effect of AGE was associated with the decrease in the oxidative stress and the preservation of Mn-SOD, GPx, and GR activities in renal cortex. These data suggest that AGE may be a useful agent for the prevention of GM-nephrotoxicity.  相似文献   
29.
Excitotoxicity elicited by overactivation of N-methyl-D-aspartate receptors is a well-known characteristic of quinolinic acid-induced neurotoxicity. However, since many experimental evidences suggest that the actions of quinolinic acid also involve reactive oxygen species formation and oxidative stress as major features of its pattern of toxicity, the use of antioxidants as experimental tools against the deleterious effects evoked by this neurotoxin becomes more relevant. In this work, we investigated the effect of a garlic-derived compound and well-characterized free radical scavenger, S-allylcysteine, on quinolinic acid-induced striatal neurotoxicity and oxidative damage. For this purpose, rats were administered S-allylcysteine (150, 300 or 450 mg/kg, i.p.) 30 min before a single striatal infusion of 1 microl of quinolinic acid (240 nmol). The lower dose (150 mg/kg) of S-allylcysteine resulted effective to prevent only the quinolinate-induced lipid peroxidation (P < 0.05), whereas the systemic administration of 300 mg/kg of this compound to rats decreased effectively the quinolinic acid-induced oxidative injury measured as striatal reactive oxygen species formation (P < 0.01) and lipid peroxidation (P < 0.05). S-Allylcysteine (300 mg/kg) also prevented the striatal decrease of copper/zinc-superoxide dismutase activity (P < 0.05) produced by quinolinate. In addition, S-allylcysteine, at the same dose tested, was able to reduce the quinolinic acid-induced neurotoxicity evaluated as circling behavior (P < 0.01) and striatal morphologic alterations. In summary, S-allylcysteine ameliorates the in vivo quinolinate striatal toxicity by a mechanism related to its ability to: (a) scavenge free radicals; (b) decrease oxidative stress; and (c) preserve the striatal activity of Cu,Zn-superoxide dismutase (Cu,Zn-SOD). This antioxidant effect seems to be responsible for the preservation of the morphological and functional integrity of the striatum.  相似文献   
30.
Nephrotic syndrome (NS) is characterized by proteinuria, oxidative stress and endogenous hyperlipidemia. Hyperlipidemia and oxidative stress may be involved in coronary heart disease and the progression of renal damage in these patients. Garlic has been suggested to be beneficial in various disease states. Some of the beneficial effects of garlic may be secondary to its hypolipidemic and antioxidant properties. Therefore, the effect of a 2% garlic diet on acute and chronic experimental NS induced by puromycin aminonucleoside (PAN) was studied in this work. Acute NS was induced by a single injection of PAN to rats which were sacrificed 10 days later. Chronic NS was induced by repeated injections of PAN to rats which were sacrificed 84 days after the first injection. Garlic treatment was unable to modify proteinuria in either acute or chronic NS, and hypercholesterolemia and hypertriglyceridemia in acute NS. However, garlic treatment diminished significantly total-cholesterol, LDL-cholesterol and triglycerides, but not HDL-cholesterol in chronic NS. Garlic induced no change in the percentage of sclerotic glomeruli in chronic NS and a significative decrease on the percentage of sclerotic area of these glomeruli (33 ± 3% in NS+Garlic group vs. 47 ± 4% in NS group, p = 0.0126). The enhanced in vivo renal H2O2 production and the diminished renal Cu, Zn-SOD and catalase activities in acute NS, and the decreased renal catalase activity in chronic NS were not prevented by garlic treatment. These data indicate that garlic treatment ameliorates hyperlipidemia and renal damage in chronic NS which is unrelated to proteinuria or antioxidant enzymes.  相似文献   
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