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71.
72.
The inhalation of a wide range of organic solvents has become popular among young adults. Toluene is one of the most commonly used solvents in industry; it is easily available and conventient to use. Many toxicologic effects on biological systems secondary to deliberate inhalation of toluene have been reported, but investigations on adverse effects associated with bone morbidity is limited. The purpose of this study is to determine bone mineralization and investigate the adverse effects of toluene on bone. The bone mineral density and content of the femoral neck of mice exposed to toluene at 300 ppm for 8 wk were measured by dual X-ray absorptiometry and found significantly reduced compared to the control group. Chronic exposure to toluene was found to affect bone metabolism, and toluene-induced changes could contribute to bone resorption and inhibition of bone formation. Toluene seems to be the responsible component for the demineralizating effects of commonly abused substances, and medical doctors must promote their education about the health hazards in those who abuse solvents especially in areas where inhalant abuse is endemic.  相似文献   
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OBJECTIVE: It has been known that there was a relation between the levels of DNA damage and the severity of the coronary artery disease (CAD). However, little is known about association of DNA damage with total antioxidant capacity (TAC) and CAD. The aim of this study is to evaluate the relationship between DNA damage, TAC and CAD. METHODS: We used the comet assay to measure DNA damage from 53 patients with angiographically documented CAD and 42 patients with angiographically documented normal coronary vessel. The extent and severity of CAD was calculated to Gensini score index. TAC of plasma was determined using a novel automated measurement method. RESULTS: Mean values of DNA damage were significantly higher in CAD patients than in the control group (p<0.001). There was a positive correlation between Gensini score index and DNA damage (r=0.590, p<0.001). Additionally, significantly positive correlations between score of DNA damage, and diabetes, smoking, obesity and hyperlipidemia were found (p<0.05). There was also a negative correlation between TAC and DNA damage (r=-0.711, p<0.001). The DNA damage was significantly higher in diabetic, smoker, hyperlipidemic and obese individuals than those without these conditions (p=0.001, p=0.006, p=0.001, p=0.004, respectively). CONCLUSIONS: These data indicate that the level of DNA damage is increased and TAC level is decreased in CAD. DNA damage is correlated with the severity of the CAD, and levels of TAC.  相似文献   
75.
The pathologic mechanisms underlying the gestational trophoblastic diseases are largely unexplored, but are thought to involve oxidative damage to the maternal vasculature and also to the placenta. In this study we have assessed the plasma levels of total antioxidant response (TAR) and the levels of endogenous DNA damage--determined by the comet assay--in peripheral blood lymphocytes from 13 women with complete hydatidiform mole (CHM) and compared these with those of 12 healthy pregnant controls and 10 healthy non-pregnant controls. Significantly lower mean levels of plasma TAR were found in patients with CHM compared with healthy pregnant controls (1.08+/-0.29 versus 1.17+/-0.14 mmol Trolox Eq/L, p<0.05) and with healthy non-pregnant controls (1.08+/-0.29 versus 1.38+/-0.12 mmol Trolox Eq/L, p<0.05). Significantly higher mean levels of endogenous DNA damage were observed in patients with CHM than in healthy pregnant controls (234.5+/-50.74 versus 125.7+/-45.4 AU, p<0.05) or in healthy non-pregnant controls (234.5+/-50.74 versus 104.0+/-49.6 AU, p<0.05). We observed an inverse correlation between the plasma TAR and the levels of endogenous DNA damage (r=-0.64, p<0.01), in that the levels of oxidative damage to the DNA were found to parallel the decrease in the plasma TAR in the CHM group. These results reveal a relationship between the extracellular and intracellular (as reflected by damage to the DNA) levels of oxidation. Our observations suggest that there is a link between the increased levels of oxidative stress and the increase in endogenous DNA damage seen in patients with CHM, as compared with those seen in normal pregnancy. However, the nature of this link, and whether it is direct or indirect, remains to be explored.  相似文献   
76.
ObjectiveHistone acetylation and deacetylation may play a role in the pathogenesis of inflammatory lung diseases. We evaluated the preventive effect of valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, on neonatal hyperoxic lung injury.MethodsForty newborn rat pups were randomized in normoxia, normoxia+VPA, hyperoxia and hyperoxia+VPA groups. Pups in the normoxia and normoxia+VPA groups were kept in room air and received daily saline and VPA (30 mg/kg) injections, respectively, while those in hyperoxia and hyperoxia+VPA groups were exposed to 95% O2 and received daily saline and VPA (30 mg/kg) injections for 10 days, respectively. Growth, histopathological, biochemical and molecular biological indicators of lung injury, apoptosis, inflammation, fibrosis and histone acetylation were evaluated.ResultsVPA treatment during hyperoxia significantly improved weight gain, histopathologic grade, radial alveolar count and lamellar body membrane protein expression, while it decreased number of TUNEL(+) cells and active Caspase-3 expression. Expressions of TGFβ3 and phospho-SMAD2 proteins and levels of tissue proinflammatory cytokines as well as lipid peroxidation biomarkers were reduced, while anti-oxidative enzyme activities were enhanced by VPA treatment. VPA administration also reduced HDAC activity while increasing acetylated H3 and H4 protein expressions.ConclusionsThe present study shows for the first time that VPA treatment ameliorates lung damage in a neonatal rat model of hyperoxic lung injury. The preventive effect of VPA involves HDAC inhibition.  相似文献   
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Some 1,5-diaryl-3-ethoxycarbonyl-2-methylpyrrole derivatives were obtained by reacting 1-aryl-3-ethoxycarbonylpent-1,4-diones and a suitable aniline derivative or sulfanilamide under Paal-Knorr pyrrole synthesis conditions. The cytotoxicity of the compounds was tested and all compounds, except for compound 2 h, showed a time-dependent increase in cytotoxic activity. Analgesic activities of the compounds were determined by using the tail-flick and tail-immersion methods; some of the compounds showed potent analgesic activity.  相似文献   
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We report here a series of 2-thiophene-sulfonamides incorporating 1-substituted aryl-1,2,3-triazolyl moieties, prepared by click chemistry from 5-ethynylthiophene-2-sulfonamide and substituted aryl azides. The new sulfonamides were investigated as inhibitors of the zinc metalloenzyme CA (EC 4.2.1.1), and more specifically against the human (h) cytosolic isoforms hCA I and II and the transmembrane, tumor-associated ones hCA IX and XII: The new compounds were medium–weak hCA I inhibitors (KIs in the range of 224–7544 nM), but were compactly, highly effective, low nanomolar hCA II inhibitors (KIs of 2.2–7.7 nM). The tumor-associated hCA IX was inhibited with KIs ranging between 5.4 and 811 nM, whereas hCA XII with inhibition constants in the range of 3.4–239 nM. The X-ray crystal structure of the adducts of two such compounds bound to hCA II (one incorporating 1-naphthyl, the other one 3-cyanophenyl moieties) evidenced the reasons of the high affinity for hCA II. Highly favorable, predominantly hydrophobic interactions between the sulfonamide scaffold and the hCA II active site were responsible for the binding, in addition to the coordination of the sulfamoyl moiety to the zinc ion. The tails of the two inhibitors adopted very diverse orientations when bound to the active site, with the naphthyltriazolyl moiety orientated towards the hydrophobic half of the active site, and the 3-cyanophenyl one pointing towards the hydrophilic half. These data may be used for the structure-based drug design of even more effective hCA II inhibitors, with potential use as antiglaucoma agents or as diuretics.  相似文献   
79.

OBJECTIVES:

Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) is a newly defined disease in neuropsychiatry and occurs with an autoimmune mechanism after Group A Beta Hemolytic Streptococcus (GABHS) infection. Tumor necrosis factor (TNF), encoded by TNF-α gene has an important role in the apoptotic mechanisms of autoimmune diseases. Recently, TNF-α polymorphisms and autoimmune/psychiatric disorders have been reported to be related. In this regard, we focused on to investigate a possible relation between the TNF-α gene promoter region−308 G/A and − 850 C/T polymorphisms and PANDAS.

MATERIALS AND METHODS:

In this study, ages of PANDAS patient and control groups were ranging from 4 years to 12-year-old. Patient group includes childhood onset PANDAS patients (n = 42) and control group includes healthy children (n = 58). Diagnoses have been carried out according to Diagnostic and Statistical Manual of Mental Disorder (DSM-IV) criteria with Affective Disorders and Schizophrenia-Present and Lifetime (KSAD-S-PL) and Children Yale-Brown Obsessive Compulsive Scale Moreover, PANDAS criteria established by the American National Psychiatry Institute have been employed for diagnoses. For identifying polymorphisms; Polymerase Chain Reaction, Restriction Fragment Length Polymorphism and Polyacrylamid Gel Electrophoresis were used.

RESULTS AND DISCUSSION:

For −308 polymorphism, 37 of 42 PANDAS patients’ results and for −850 C/T polymorphism, 38 of 42 PANDAS patients’ results were obtained. According to our statistical analysis there is a positive relationship between PANDAS patients for −308 G/A polymorphism but not for −850 C/T polymorphism. There is no positive relationship between −308 G/A polymorphism and antistrep-tolysin O (ASO) titers and no relationship between −850 C/T polymorphism and ASO titers. We found, however, positive relationship between genders of patients (boys) and the disease. According to our results, we propose that the AA polymorphism of −308 G/A polymorphism can be used as a molecular indicator for PANDAS.  相似文献   
80.
The present study aims to evaluate the effect of selenium supplementation on lipid peroxidation and lactate levels in rats subjected to acute swimming exercise. Thirty-two adult male rats of Sprague–Dawley type were divided into four groups. Group 1, control; group 2, selenium-supplemented; group 3, swimming control; group 4, selenium-supplemented swimming group. The animals in groups 2 and 4 were supplemented with (i.p.) 6 mg/kg/day sodium selenite for 4 weeks. The blood samples taken from the animals by decapitation method were analyzed in terms of erythrocyte-reduced glutathione (GSH), serum glutathione peroxidase (GPx) and superoxide dismutase (SOD), and plasma malondialdehyde (MDA) and lactate using the colorimetric method, and serum selenium values using an atomic emission device. In the study, the highest MDA and lactate values were found in group 3, while the highest GSH, GPx and SOD values were obtained in group 4 (p < 0,001). Group 2 had the highest and group 3 had the lowest selenium levels (p < 0,001). Results of the study indicate that the increase in free radical production and lactate levels due to acute swimming exercise in rats might be offset by selenium supplementation. Selenium supplementation may be important in that it supports the antioxidant system in physical activity.  相似文献   
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