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161.
Quercetin, an antioxidant derived from plants, can play a beneficial role in the protection of various tissues against ischemia-reperfusion injuries (IRI). The purpose of the present research was to investigate the protective effects of quercetin on gastrocnemius muscle ischemia-reperfusion. A total of 80 adult male Wistar rats (weights: 250–300 g) were divided into ten groups (n = 8 per group). We used silk 6.0 surgical thread to create a knit to occlude the femoral artery and vein for 3 hr. The treated groups, which comprised half of each experimental group, received intraperitoneal injections of 150 mg/kg quercetin after the ischemia. Blood flow was subsequently reestablished in the reperfusion phase. The rats were kept in reperfusion for 3, 7, 14, or 28 days after which they were killed with high doses of anesthetic drugs, and the gastrocnemius muscles were removed and fixed. Tissue processing, hematoxylin and eosin and toluidine blue staining, and immunohistochemistry were used to assess tumor necrosis factor-α (TNF-α) and nuclear factor κB (NF-κB) levels. A comparison between treated and untreated ischemic sites showed that on the third day of reperfusion, the severity of edema and NF-κB level decreased significantly; on the 7th day of reperfusion, the severity of edema and the levels of TNF-α and NF-κB decreased significantly; and on the 14th day of reperfusion, all of the parameters showed significant decreases. On the 28th day of reperfusion, there were significantly decreased levels of TNF-α and NF-κB, and decreased mast cell infiltration when compared with the untreated groups. According to the results, administration of quercetin after ischemia could significantly prevent gastrocnemius muscle IRI.  相似文献   
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Abstract

Phosphorus (P) is the most important macronutrient next to nitrogen for the growth and development of plants. But often unavailable for plants because of its high reactivity with many soil constituents. Thus, the use of phosphate solubilizing bacteria (PSBs) as biofertilizers seems to be an effective way to resolve the soluble phosphorus availability in soil. The present study was conducted to isolate and characterize rock PSB associated with the rhizosphere of wheat (Triticum aestivum L.) from fourteen different wheat-growing sites of Meknes region in Morocco. A total of one hundred ninety-eight (198) rock PSBs were isolated employing NBRIP medium amended with rock phosphate (RP), out of which five strains (A17, A81, B26, B106, and B107) were selected for their strong ability to dissolve RP and were tested in vitro for plant growth-promoting (PGP) traits including production of indole acetic acid (IAA), siderophores, hydrogen cyanide (HCN), and antifungal activity, as well as their response to the effect of extrinsic and intrinsic stress. The 16S rRNA gene sequencing and phylogenetic analysis identified these isolates belong to four genera, Pantoea, Pseudomonas, Serratia, and Enterobacter. The phosphate solubilization index (SI) of selected isolates ranged between 2.3 and 2.7, and the amount of solubilized phosphorus in the liquid medium varied from 59.1 to 90.2 µg mL?1. HPLC analysis revealed that all the selected isolates produced multiple organic acids (oxalic, citric, gluconic succinic, and fumaric acids) from glucose under aerobic conditions. Except for the A81 strain, all selected isolates were able to produce IAA ranging between 2.9 and 21.2 µg mL?1. The isolates A17, B26, and B107 showed the ability to produce siderophores ranging from 79.3 to 20.8% siderophore units. Only two strains (A17 and B26) were able to produce HCN. All selected isolates showed good resistance against different environmental stresses like 10–50?°C temperature, 0.5–2?g L?1 salt concentration and 4.5–9?pH range, and against different antibiotics. The antagonistic effect showed that among the five selected strains, only two strains (B26 and A17) were able to suppress the growth of tested fungi. This study clearly indicates that our selected rock PSBs can be used as biofertilizers for grain crops after studying their interaction with the host crop and field evaluation.  相似文献   
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This study deals with the simultaneous determination of sucrose and trehalose in olive leaf samples, with easy sample preparation step, by second derivative UV–Vis spectrophotometry and partial least squares technique. A training set consisting of 31 binary mixture solutions was applied for the construction of PLS model. The proposed procedure was successfully applied for the simultaneous determination of both carbohydrates in laboratory prepared mixtures and in real samples. The real samples were from different growth stages of olive plant. The root mean square error of prediction was determined to be 1.95 and 2.06 for sucrose and trehalose, respectively. Also, limit of detection was 0.21 ppm for sucrose and 0.26 ppm for trehalose. The proposed procedure is rapid, simple, and easy to perform which can be used for routine analysis of both carbohydrates in plant leaves.  相似文献   
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Molecular Biology Reports - Numerous pieces of evidence show that many environmental and genetic factors can cause male infertility. Much research in recent years has investigated the function of...  相似文献   
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Three hundred female broilers were assigned to five groups with six replicates and were fed with either a basal diet (two control groups) or the basal diet supplemented with 800-mg vitamin C/kg (Vit C group), 1,200-μg Cr+3 from chromium (Cr) chloride/kg (Cr group) or 800-mg Vit C and 1,200-μg Cr+3 from Cr chloride/kg (Vit C?+?Cr group) from 42 to 49 days of age. Treatments did not affect performance. Transport decreased insulin level in the control and Cr groups and increased glucose/insulin (G/I) ratio in the groups. The level of insulin was higher in the Vit C?+?Cr group than those in the control and Cr groups after the transport. The G/I ratio was lowest in the Vit C?+?Cr group after the transport. The transport significantly decreased triiodothyronine (T3) concentration in the groups except the Vit C?+?Cr group and only increased thyroxin (T4) concentration in the Vit C?+?Cr group. The T3/T4 ratio was significantly decreased in the groups except the Cr group by transport. The T3/T4 ratio was greatest in the Vit C?+?Cr group before the transport. Alkaline phosphatase activity was decreased in the Vit C?+?Cr group due to transport. Transport decreased triglyceride levels in the groups and also decreased low-density lipoprotein cholesterol levels in the Vit-C-supplemented groups. Transport increased malondialdehyde concentration in the control and Vit C groups and also increased glutathione peroxidase (GPx) activity in the Cr-fed groups. The GPx activity was higher in the Vit C?+?Cr group than those in the control and Cr groups after the transport. Ferric reducing/antioxidant power (FRAP) value was decreased in the Vit C and Cr groups by transport. Either alone or in combination, Cr increased the FRAP value before the transport. Neither transport nor treatments had significant effects on the duration of tonic immobility (TI) and number of inductions to induce TI.  相似文献   
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