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91.
The prevalence of obesity in children has increased dramatically over the last 20-30 years in developed countries. The aim of this study was to evaluate the oxidative and antioxidant status and any correlation with leptin in obese prepubertal children. A cross-sectional study was made of healthy children from ten elementary schools in the province of Elazig, Eastern Turkey. Blood samples were drawn from children comprising obese and control groups, on a visit to their school in the morning after an overnight fast. The mean body mass index (BMI) was 24.03 +/- 4.09 kg/m(2) in the obese group and was 17.51 +/- 2.33 kg/m(2) in the control group. Mean plasma leptin concentration was significantly higher in the obese children. Homocysteine and malondialdehyde (MDA) levels were also significantly higher in the obese group. In contrast superoxide dismutase (SOD) and glutathione peroxidase activities were significantly decreased in the obese group (p < 0.001). In conclusion, in prepubertal obese children oxidative stress was increased and MDA and homocysteine levels were well correlated with serum leptin level and BMI. In contrast with the increase in oxidative stress, antioxidant activities of SOD and glutathione peroxidase were decreased in obese prepubertal children.  相似文献   
92.
In this study, we evaluated the hypothesis that long term dietary restriction would have beneficial effects on the oxidative stress and antioxidant enzyme systems in liver, heart and kidney in adult male rats undergoing different intensities of swimming exercise. Sixty male, Sprague-Dawley rats were assigned as either dietary restricted on every other week day (DR) or fed ad libitum (AL) groups, and each group was further subdivided into sedentary, endurance swimming exercise training (submaximal exercise) and exhaustive swimming exercise (maximal exercise) groups. Animals in the submaximal exercise group swam 5 days/week for 8 weeks, while maximal exercise was performed as an acute bout of exercise. In parallel with the increase in the intensity of the exercise, the degree of lipid peroxidation and protein oxidation were increased in both the DR and AL groups; however the rate of increase was lower in the DR group. Reduced glutathione (GSH), glutathione peroxidase (GSH-Px) and glutathione reductase (GR) enzyme activities were lower in the DR group than in the AL group. In parallel with the increase in exercise intensity, GSH and GR enzyme activities decreased, whereas an increase was observed in GSH-Px enzyme activity. In conclusion, the comparison between the DR and AL groups with the three swimming exercise conditions shows that the DR group is greatly protected against different swimming exercise-induced oxidative stress compared with the AL group.  相似文献   
93.
BACKGROUND/AIMS: Exposure to diabetes in utero has been established as a significant risk factor for some of components of metabolic syndrome. A few studies have examined relationship between the metabolic syndrome and echocardiographic left ventricular (LV) mass. We aimed to investigate relationship between abdominal aortic intima-media thickness (aIMT), LV mass and lipid profile in macrosomic newborns. METHODS: Abdominal aIMT was measured in 30 macrosomic neonates of diabetic mothers (group A), 30 macrosomic neonates of healthy mothers (group B) and 30 healthy neonates (group C). Lipid profile and LV mass were determined. RESULT: Mean aIMT was significantly higher in groups A and B (0.489 +/- 0.015, 0.466 +/- 0.019 mm, respectively) than in controls (0.375 +/- 0.024 mm). Weight-adjusted aIMT in group A was significantly higher than in groups B and C. Macrosomia was associated with increased lipid concentrations. Both LV mass indexed for BSA (body surface area) and birth weight measurements were significantly increased in group A compared with control. CONCLUSIONS: Macrosomic neonates of diabetic mothers have significant aIMT and LV mass indexed for BSA and birth weight with lipid alterations. It might play a role in the pathogenesis of atherosclerosis in adult life.  相似文献   
94.
Two elemanolide sesquiterpenes and two eudesmane-type sesquiterpene glycosides named hierapolitanins A-D, were isolated, together with five known compounds, two flavones; hispidulin and jaceosidin, a flavon-C-glycoside, shaftoside, a flavonol glycoside, kaempferol-3-O-rutinoside and a neolignan, dehydrodiconiferyl alcohol from the aerial parts of Centaurea hierapolitana Boiss. (Asteraceae). Structure elucidations were based on spectroscopic evidence.  相似文献   
95.
Molecular motors, which use energy from ATP hydrolysis to take nanometer-scale steps with run-lengths on the order of micrometers, have important roles in areas such as transport and mitosis in living organisms. New techniques have recently been developed to measure these small movements at the single-molecule level. In particular, fluorescence imaging has contributed to the accurate measurement of this tiny movement. We introduce three single-molecule fluorescence imaging techniques which can find the position of a fluorophore with accuracy in the range of a few nanometers. These techniques are named after Hollywood animation characters: Fluorescence Imaging with One Nanometer Accuracy (FIONA), Single-molecule High-REsolution Colocalization (SHREC), and Defocused Orientation and Position Imaging (DOPI). We explain new understanding of molecular motors obtained from measurements using these techniques.  相似文献   
96.
Since the discovery of the megaherbivore Arsinoitherium zitteli Beadnell (early Oligocene of Egypt), the extinct order Embrithopoda has remained an enigmatic group, with disputed affinities among ungulates. In this study, new specimens of Palaeoamasia kansui from the early Palaeogene of Turkey are described and a synthetic dental terminology is proposed for embrithopods. Based on 130 cranial–mandibular and dental characters, the first phylogenetic analysis of embrithopods is carried out in aim to enhance the position of Palaeoamasia within embrithopods. The monophyly of Embrithopoda is confirmed, following the topology (Phenacolophus (Namatherium (Arsinoitheriinae, Palaeamasiinae))). However, phylogenetic relationships between Eurasian embrithopods (Palaeoamasiinae: Palaeoamasia, Crivadiatherium and Hypsamasia) remain unresolved. The integration of all embrithopod genera within a cladistic analysis encompassing a wider taxonomic sample (Condylarthra, Afrotheria/Paenungulata and Laurasiatheria) also supports Embrithopoda as being monophyletic, but questions the position of both Phenacolophus and Namatherium within Embrithopoda. Finally, possible faunal exchange events are proposed based on three hypothesized scenarios between Eurasia and Arabia–Africa during the early Palaeogene.  相似文献   
97.
The relationship between the stem cells and the bone turnover in uremic bone disease due to chronic renal failure (CRF) is not described. The aim of this study was to investigate the effect of bone turnover status on stem cell properties. To search for the presence of such link and shed some light on stem-cell relevant mechanisms of bone turnover, we carried out a study with mesenchymal stem cells. Tissue biopsies were taken from the abdominal subcutaneous adipose tissue of a CRF patient with secondary hyperparathyroidism with the high turnover bone disease. This patient underwent parathyroidectomy operation (PTX) and another sample was taken from this patient after PTX. A CRF patient with adynamic bone disease with low turnover and a healthy control were also included. Mesenchymal stem cells isolated from the subjects were analyzed using proteomic and molecular approaches. Except ALP activity, the bone turnover status did not affect common stem cell properties. However, detailed proteome analysis revealed the presence of regulated protein spots. A total of 32 protein spots were identified following 2D gel electrophoresis and MALDI-TOF/TOF analyzes. The identified proteins were classified into seven distinct groups and their potential relationship to bone turnover were discussed. Distinct protein expression patterns emerged in relation to the bone turnover status indicate a possible link between the stem cells and bone turnover in uremic bone disease due to CRF.  相似文献   
98.
Demirhan  Osman  Tunç  Erdal 《Chromosoma》2022,131(4):225-237
Chromosoma - Cytogenetic analysis is helpful in diagnostic workup of patients having prenatal or early postnatal medical problems and provides a basis for genetic counseling or deciding on clinical...  相似文献   
99.
ABSTRACT

Obesity is a chronic disease that is characterized by increased body fat owing to imbalance between consumed and expended energy. Inflammation generally is accompanied by accumulation of excess lipid in adipose tissue and liver. High mobility group box-1 (HMGB1) participates in the pathogenesis of inflammatory diseases. We investigated the relation of the number of HMGB1 positive cells to body mass index (BMI), liver inflammation and the number of Kupffer cells. We divided 18 female Wistar albino rats into two groups: group 1, untreated control fed normal commercial rat diet and group 2, obese rats fed a special diet containing 40% fat. The plasma concentrations of cholesterol, glucose, superoxide dismutase enzyme (SOD) and catalase activities were measured for all animals. The numbers of hepatocytes, Kupffer cells and HMGB1 positive cells were counted using stereological methods. The mean numbers of Kupffer cells and HMGB1 positive cells were higher for group 2 than for group 1. The concentrations of plasma cholesterol and glucose levels also were higher in group 2. Plasma levels of SOD and catalase were significantly lower in group 2 compared to group 1. The number of HMGB1 cells was related directly to BMI and inflammation. The role of HMGB1 was demonstrated for the liver of the obese group. We demonstrated the relations among HMGB1, BMI, obesity and inflammation.  相似文献   
100.
A mural excavated at the Neolithic Çatalhöyük site (Central Anatolia, Turkey) has been interpreted as the oldest known map. Dating to ∼6600 BCE, it putatively depicts an explosive summit eruption of the Hasan Dağı twin-peaks volcano located ∼130 km northeast of Çatalhöyük, and a birds-eye view of a town plan in the foreground. This interpretation, however, has remained controversial not least because independent evidence for a contemporaneous explosive volcanic eruption of Hasan Dağı has been lacking. Here, we document the presence of andesitic pumice veneer on the summit of Hasan Dağı, which we dated using (U-Th)/He zircon geochronology. The (U-Th)/He zircon eruption age of 8.97±0.64 ka (or 6960±640 BCE; uncertainties 2σ) overlaps closely with 14C ages for cultural strata at Çatalhöyük, including level VII containing the “map” mural. A second pumice sample from a surficial deposit near the base of Hasan Dağı records an older explosive eruption at 28.9±1.5 ka. U-Th zircon crystallization ages in both samples range from near-eruption to secular equilibrium (>380 ka). Collectively, our results reveal protracted intrusive activity at Hasan Dağı punctuated by explosive venting, and provide the first radiometric ages for a Holocene explosive eruption which was most likely witnessed by humans in the area. Geologic and geochronologic lines of evidence thus support previous interpretations that residents of Çatalhöyük artistically represented an explosive eruption of Hasan Dağı volcano. The magmatic longevity recorded by quasi-continuous zircon crystallization coupled with new evidence for late-Pleistocene and Holocene explosive eruptions implicates Hasan Dağı as a potential volcanic hazard.  相似文献   
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