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91.
AIM To investigate the effect of sinomenine (SN) on the damage of human neuroblastoma SK-N-SH cells induced by 1-methyl-4-4 phenylpyridine (MPP+) and its mechanism for exploring the pathogenesis of Parkinson disease. METHODS SN was used to treat MPP+-induced SK-N-SH cells. The levels of malondialdehyde (MDA) and glutathione (GSH) in cell culture supernatants were measured by ELISA. The apoptosis was analyzed by flow cytometry. The protein expression levels of Bcl-2 and Bax were determined by Western blot. The expression levels of long noncoding RNA ANRIL and microRNA-626 (miR-626) were detected by RT-qPCR. Dual-luciferase reporter assay was used to evaluate the relationship between ANRIL and miR-626. After ANRIL small interfering RNA was transfected into SK-N-SH cells, the effects of ANRIL expression knock-down on MPP+-induced SK-N-SH cell apoptosis, the protein expression levels of Bcl-2 and Bax, and the levels of MDA and GSH in cell culture supernatants were examined. RESULTS After treatment with MPP+, the apoptotic rate, Bax protein level and ANRIL expression in SK-N-SH cells were increased (P<0.05), and the Bcl-2 protein level and miR-626 expression were decreased (P<0.05). The level of MDA in cell culture supernatants was increased (P<0.05), and the level of GSH was decreased (P<0.05). After SN treatment or ANRIL expression knock-down, decreased apoptotic rate, Bax protein level and ANRIL expression (P<0.05), and increased Bcl-2 protein level and miR-626 expression in MPP+-induced SK-N-SH cells were observed (P<0.05). The level of MDA in the cell culture supernatants was decreased (P<0.05), and the level of GSH was increased (P<0.05). CONCLUSION SN attenuates MPP+-induced damage in SK-N-SH cells by regulating ANRIL/miR-626 signaling pathway.  相似文献   
92.
AIM To explore the effects of oxidative stress and inflammatory response on kidney injury induced by hyperthyroidism in mice. METHODS Forty male Kunming mice were randomly divided into control group (n=20) and L-thyroxine (T4) group (n=20). The mice in T4 group were intraperitoneally injected with T4 diluent at a dose of 1 mg/kg to induce hyperthyroidism, and those in control group were injected with normal saline of the same volume. After 7 weeks, the mice were weighed and dissected, the kidneys were removed and weighed, and the length of tibia was also measured. The activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) in the kidney tissues were detected. The pathological changes of the kidney tissues were observed by HE staining. The levels of 4-hydroxynonenal (4-HNE)-modified proteins, interleukin-1 receptor-associated kinase 1 (IRAK1) and tumor necrosis factor receptor-related factor 6 (TRAF6) were determined by Western blot and immunohistochemistry. RESULTS Compared with control group, the body weight of the mice was decreased, while the kidney size and weight were increased significantly in T4 group. In addition, the ratios of kidney weight/body weight and kidney weight/tibia length were also increased (P<0.05). In T4 group, the renal tubules were enlarged, and the epithelial cells of renal tubules were swollen and exfoliated, with vacuolar degeneration. Furthermore, reduced SOD activity, and increased MDA content and 4-HNE-modified proteins were found in T4 group, all of which were related to oxidative stress (P<0.05). The levels of inflammation-related proteins IRAK1 and TRAF6 were significantly increased in T4 group (P<0.05). CONCLUSION Excessive T4 may lead to kidney hypertrophy and injury in mice, and the mechanism may be related to oxidative stress and inflammatory response.  相似文献   
93.
AIM To investigate the role of curcumin (CUR) in lung ischemia/reperfusion (I/R) injury (LIRI) and its relationship with autophagy. METHODS 40 SD rats were randomly divided into sham operation (sham) group, I/R group, solvent (DMSO) group, CUR group and CUR+rapamycin (CUR-Rap) group. The rats were intraperitoneally injected with normal saline, DMSO, CUR or CUR+Rap before operation. After the rat LIRI model was established, the lung tissues were taken to measure W/D, TLW, IAR, and the contents of SOD and MDA were also measured to indicate the oxidative stress level. Light and electron microscopes were used to observed the morphology and ultrastrucure of lung tissues. The expression levels of autophagy-related proteins were determined by Western blot to evaluate autophagy levels. RESULTS Compared with sham group, wet weight/dry weight (W/D), total lung water (TLW), injured alveoli rate(IAR) and malondialdehyde (MDA) content in all other groups were increased, superoxide dismutase (SOD) activity was decreased, the levels of autophagy were increased (P<0.05), and lung tissue injury and cell ultrastructural damage were aggravated in CUR group. Compared with DMSO group, W/D, TLW and IAR and MDA content were decreased, SOD activity was decreased, autophagy levels were also decreased (P<0.05), and lung tissue and cell ultrastructural damage were attenuated. Compared with CUR group, W/D, TLW, IAR and MDA content were increased, SOD activity declined, the autophagy levels were increased (P<0.05), and damage of lung tissues and cells were more serious in CUR-Rap group. CONCLUSION Curcumin attenuates the lung I/R injury in rats, and its mechanism may be related to the reduction of oxidative stress and the inhibition of autophagy.  相似文献   
94.
95.
研究了日粮维生素E、硒水平对熟化过程中牛肉氧化稳定性的影响。选择16头体重420~560kg的健康晋南牛阉牛,按体重分为4组,每组4头,试验期为2个月。试验采用2×2因子完全随机设计:维生素E的补饲水平为每头每天0和1000IU,硒的添加水平为0 10和0 40mg/kg。结果表明:与未补饲VE组相比,补饲1000IUVE可显著提高血浆和臀中肌α 生育酚含量(P<0 004),日粮中添加0 10和0 40mg/kg硒对组织α 生育酚含量影响差异不显著(P>0 05);日粮中添加0 40mg/kg硒组全血和臀中肌硒含量显著高于0 10mg/kg组(P<0 002);补饲1000IUVE和/日粮中添加0 40mg/kg硒可显著提高全血GPx(谷胱甘肽过氧化物酶)和熟化过程中臀中肌GPx酶活力(P<0 01),但对组织SOD(超氧化物歧化酶)酶活力影响差异不显著(P>0 05);补饲1000IUVE可显著抑制熟化过程中牛肉的脂质氧化(P<0 001),对牛肉的保水性能和颜色稳定性影响差异不显著(P>0 05);虽然提高日粮硒水平可明显增强熟化过程中牛肉GPx酶活力,但GPx酶活力的提高没有降低牛肉的TBARS值、滴水损失和METMB(高铁肌红蛋白)含量,该结果提示不同日粮硒水平对牛肉氧化稳定性没有显著影响。  相似文献   
96.
AIM To investigate the effects of astragaloside on the levels of sex hormone and oxidative stress in rats with polycystic ovary syndrome (PCOS). METHODS Female SD rats (n=60) were randomly divided into normal control group, model group, Diane-35 (0.339 2 mg/kg) group, low dose astragaloside (12.5 mg/kg) group and high dose astragaloside (50 mg/kg) group, with 12 rats in each group. The PCOS model was induced by letrozole (1 mg/kg), which was administered by gavage once a day for 3 weeks. After administration, the estrus cycle of the rats was observed by vaginal smear, and the ovarian index was calculated. HE staining was used to observe the histopathological changes of the ovaries. Serum levels of the sex hormones testosterone (T), estradiol (E2), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured by ELISA. The levels of superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) in serum and ovarian tissue were detected by colorimetry, and the protein levels of steroidogenetic acute regulatory protein (StAR) and apoptosis-related proteins cleaved caspase-3, Bax and Bcl-2 in ovarian tissue were detected by Western blot. RESULT Compared with control group, the oestrous cycle of the rats in model group was disorder, and the ovarian index was increased, ovary was polycystic. The serum levels of T, LH and MDAwere significantly increased (P<0.05), while the contents of E2, FSH and the activities of GSH-Px and SOD were significantly decreased (P<0.05). The levels of MDA, StAR, cleaved caspase-3 and Bax proteins in ovarian tissue were significantly up-regulated (P<0.05). GSH-Px and SOD activities and Bcl-2 protein levels were significantly down-regulated (P<0.05). CONCLUSION Astragalosideeffectively balances the levels of sex hormone in PCOS rats and relieves the oxidative stress injury, the mechanism may be related to the inhibition of StAR expression.  相似文献   
97.
Both melamine and cyanuric acid have low toxicity, but together they may cause serious lesions to the kidney, via an unknown mechanism. This study was aimed to estimate whether lesions to the kidney were relative to oxidative damage and hypoxia in the kidney after mice exposed to 1 mg/kg/day, 5 mg/kg/day or 25 mg/kg/day of a mixture of melamine and cyanuric acid for 13 weeks. Pathological changes to the kidneys, oxidative stress and energy parameters and hypoxia-inducible factor-1α (HIF-1α) change in the kidneys were evaluated. Pathological changes were found in the distal tubules of kidneys, such as crystals, proteinaceous casts and compensatory expansion, indicating that the mixture induced toxicity to the kidney. The activities of total antioxidant capacity (TAC) and superoxide dismutase (SOD) and the concentration of glutathione (GSH) decreased, while the concentrations of lipid peroxidation (MDA) and protein carbonyl groups (PC) increased after exposure to the mixture, demonstrating that the mixture resulted in imbalance of antioxidant and reactive oxygen species (ROS) and excessive ROS induced oxidant damage to lipid and proteins in kidneys. The activities of malate dehydrogenase (MDH) and succinate dehyrogenase (SDH) decreased, however, the activity of lactic dehydrogenase (LDH) and the concentration of HIF-1α increased after exposure to the mixture. Accordingly, it was concluded that the mixture resulted in a hypoxic state in kidneys and that both oxidative stress and hypoxia contributed to the lesion of kidneys. The exact cause of oxidative damage and hypoxia is not clear, it might be caused by either a direct effect or by an indirect effect, which is secondary to substantial renal damage caused by tubular obstruction due to crystal formation.  相似文献   
98.
张毅宾  李拥军 《现代农业科技》2023,(16):188-191+199
绿原酸是一种植物提取物,具有抗氧化、抑菌、抗病毒和抑制突变等多种作用。研究发现,绿原酸在畜禽繁殖生产方面具有重要作用。本文从抗氧化活性、抑菌、提高畜禽生长性能等方面阐述了绿原酸在畜禽繁殖生产中的应用,并从抗氧化机理、抑菌机理、提高畜禽生长性能的机理等方面分析了绿原酸的作用机理,以期为促进绿原酸在畜禽繁殖生产中的应用提供参考。  相似文献   
99.
AIM:To explore the role of superoxide dismutase (SOD) and malondialdehyde (MDA) in chronic pancreatitis (CP) induced by dibutyltin dichloride (DBTC) combined with ethanol, and the mechanisms for prevention and treatment of pancreatic fibrosis by Chaihushugansan. METHODS:The KM mice were randomly divided into control group, CP group (DBTC combined with ethanol) and Chaihushugansan group (CP+Chaihushugansan). Except for control group, the mice in other groups were intravenously injected in tail with DBTC (8 mg/kg) and drank 10% ethanol. The mice in Chaihushugansan group were administered intragastrically with Chaihushugansan (6 g·kg-1·d-1) at the following experimenal period. Before modeling and 1 week, 2 weeks, 4 weeks and 8 weeks after modeling, the mice were anesthetized and sacrificed. The activity of amylase and the content of hyaluronic acid in the serum were measured. The morphology and the degree of fibrosis in the pancreas were observed by HE staining. The activity of SOD and the level of MDA in the pancreas homogenate were analyzed. The protein of pancreas was extracted to detect the expression of type I collagen by Western blotting. RESULTS:DBTC combined with ethanol induced CP with increased serum amylase and hyaluronic acid levels, while the serum amylase and hyaluronic acid levels in Chaihushugansan group were significantly lowered (P<0.05). In 1 week, 2 weeks, 4 weeks and 8 weeks, the pancreas were obviously injured and appeared different degrees of fibrosis. The content of MDA and the expression of type I collagen in the increased significantly, but the SOD was decreased. In Chaihushugansan group, the pathological damage and the degree of fibrosis of the pancreas were improved. The level of MDA and type I collagen expression in the pancreas were significantly reduced, but the SOD was increased. CONCLUSION: The oxidative stress may take part in the development of CP. Inhibition of oxidative stress in the pancreas is one of the mechanisms that Chaihushugansan attenuates the development of CP.  相似文献   
100.
Ying-Hua ZHANG 《园艺学报》2014,30(12):2161-2165
AIM: To investigate the effects of sulindac on oxidative stress in autism. METHODS: With an autistic model induced by prenatal exposure to valproic acid (VPA), we detected the expression of the signaling molecules of canonical Wnt pathway in the prefrontal cortex (PFC) and hippocampus (HC) of autistic rats treated with sulindac. The protein expression levels of glycogen synthase kinase 3β (GSK-3β), β-catenin and 4-hydroxynonenal (4-HNE) were observed by Western blotting. The mRNA expression of thioredoxin(Trx)1 and Trx2 was assessed by semi-quantitative RT-PCR.RESULTS: The protein level of GSK-3β and mRNA levels of Trx1 and Trx2 were lower, whereas the protein expression levels of β-catenin and 4-HNE were higher in VPA group than those in control group. In contrast, the protein levels of GSK-3β were significantly higher in the animals treated with both VPA and sulindac than those in VPA group, while the levels of β-catenin and 4-HNE were decreased.CONCLUSION: Sulindac attenuates oxidative stress in the pathogenesis of autism, suggesting the up-regulation of the Wnt/β-catenin signaling pathway disrupts oxidative homeostasis and further facilitates susceptibility to autism.  相似文献   
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