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排序方式: 共有640条查询结果,搜索用时 15 毫秒
81.
82.
West DS Raczynski JM Phillips MM Bursac Z Heath Gauss C Montgomery BE 《Obesity (Silver Spring, Md.)》2008,16(3):630-636
Objective: Examine the accuracy of parental weight perceptions of overweight children before and after the implementation of childhood obesity legislation that included BMI screening and feedback. Methods and Procedures: Statewide telephone surveys of parents of overweight (BMI ≥ 85th percentile) Arkansas public school children before (n = 1,551; 15% African American) and after (n = 2,508; 15% African American) policy implementation were examined for correspondence between parental perception of child's weight and objective classification. Results: Most (60%) parents of overweight children underestimated weight at baseline. Parents of younger children were significantly more likely to underestimate (65%) than parents of adolescents (51%). Overweight parents were not more likely to underestimate, nor was inaccuracy associated with parental education or socioeconomic status. African‐American parents were twice as likely to underestimate as whites. One year after BMI screening and feedback was implemented, the accuracy of classification of overweight children improved (53% underestimation). African‐American parents had significantly greater improvements than white parents (P < 0.0001). Discussion: Parental recognition of childhood overweight may be improved with BMI screening and feedback, and African‐American parents may specifically benefit. Nonetheless, underestimation of overweight is common and may have implications for public health interventions. 相似文献
83.
Banfić L Vrkić Kirhmajer M Vojković M Strozzi M Smalcelj A Lasić Z 《Collegium antropologicum》2008,32(2):385-390
Access site complications are major source of morbidity following cardiac catheterization. Their incidence varies in the literature because of multiple definitions and methods of determining the presence of particular complication. The aim of this prospective study was to determine the incidence of access site complications following cardiac catheterization using arterial duplex ultrasonography. A total of 319 consecutive patients, who had cardiac catheterization underwent femoral artery duplex study 24 to 48 hours following manual hemostasis. Diagnostic angiogram had 232 (71.8%) while 87 (28.2%) had percutaneous coronary intervention (PCI). Femoral artery duplex ultrasound was normal in 247 (77.4%). Haematoma was found in 48 (15.1%), pseudoaneurysm in 17 (5.3%), AV fistula in 2 (0.6%) and dissection of the femoral artery in 5 (1.6%) patients. Baseline demografic characteristics were similar in group with normal duplex study and group with detected complication. Pseudoaneurysm and AV fistula were more commonly observed in patients following PCI than diagnostic angiogram (9.2% vs. 4.7%, p<0.001). Patients with documented complications more frequently had concomitant administration of antiplatelet and anticoagulant medication compared to the patients without complications (p=0.003). Hemodynamic disturbances (hypotension and bradycardia) during manual compression were more frequent in patients with complication (11% vs. 4.5%, p=0.047). Low threshold for use of duplex ultrasound should be exercised in patients following cardiac catheterization to establish the presence of access site complications. Special attention is needed in the setting of aggressive antiplatelet and anticoagulant therapy, interventional procedures and hemodynamic disturbances during manual hemostas. 相似文献
84.
Bandi E Jevsek M Mars T Jurdana M Formaggio E Sciancalepore M Fumagalli G Grubic Z Ruzzier F Lorenzon P 《American journal of physiology. Cell physiology》2008,294(1):C66-C73
The aim of this study was to elucidate the mechanisms responsible for the effects of innervation on the maturation of excitation-contraction coupling apparatus in human skeletal muscle. For this purpose, we compared the establishment of the excitation-contraction coupling mechanism in myotubes differentiated in four different experimental paradigms: 1) aneurally cultured, 2) cocultured with fetal rat spinal cord explants, 3) aneurally cultured in medium conditioned by cocultures, and 4) aneurally cultured in medium supplemented with purified recombinant chick neural agrin. Ca(2+) imaging indicated that coculturing human muscle cells with rat spinal cord explants increased the fraction of cells showing a functional excitation-contraction coupling mechanism. The effect of spinal cord explants was mimicked by treatment with medium conditioned by cocultures or by addition of 1 nM of recombinant neural agrin to the medium. The treatment with neural agrin increased the number of human muscle cells in which functional ryanodine receptors (RyRs) and dihydropyridine-sensitive L-type Ca(2+) channels were detectable. Our data are consistent with the hypothesis that agrin, released from neurons, controls the maturation of the excitation-contraction coupling mechanism and that this effect is due to modulation of both RyRs and L-type Ca(2+) channels. Thus, a novel role for neural agrin in skeletal muscle maturation is proposed. 相似文献
85.
The antioxidant activity and contents of various polyphenol classes in the seeds of 20 soybean hybrids were evaluated. Total polyphenols, tannins and proanthocyanidins were determined after extraction of plant material with 70% aqueous acetone. In addition, flavonoid content was determined. Antioxidant activity of seed extracts was evaluated by DPPH free radical scavenging activity assay. A positive linear correlation between antioxidant activity and contents of total phenols, tannins and proanthocyanidins was established. The highest antioxidant activity was observed in the extracts of hybrids which have higher levels of all polyphenol classes examined. The most of the single-cross hybrids were poor in tannins which recommend them as good source for ensiled livestock feed. Results suggested that polyphenol content should be considered as an important feature of the soybean seed. 相似文献
86.
Zoran Stanimirovic Jevrosima Stevanovic Slobodan Jovanovic Marko Andjelkovic 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2005,588(2):152-157
Apitol®, with cymiazole hydrochloride as the active ingredient, is used in bee-keeping against the ectoparasitic mite Varroa destructor. The preparation was evaluated for genotoxicity in cultured human peripheral blood lymphocytes. Sister chromatid exchange, the mitotic index and the cell proliferation index were determined for three experimental concentrations of Apitol® (0.001, 0.01 and 0.1 mg/ml). All concentrations significantly (p < 0.001) increased the mitotic index (MI = 7.35 ± 0.18%, 8.31 ± 0.20% and 12.33 ± 0.25%, respectively), the proliferative index (PI = 1.83 ± 0.01, 1.84 ± 0.01 and 1.88 ± 0.02, respectively) and the frequency of sister chromatid exchange (SCE = 8.19 ± 1.81, 8.78 ± 1.80 and 13.46 ± 1.88, respectively), suggesting that cymiazole hydrochloride has genotoxic potential. 相似文献
87.
Neven Zarkovic Zoran Ilic Mislav Jurin R. Jrg Schaur Herbert Puhl Hermann Esterbauer 《Cell biochemistry and function》1993,11(4):279-286
The aim of this study was to analyze the growth response of HeLa cells over a prolonged period of time to a single exposure of physiological and supraphysiological concentrations of 4-hydroxynonenal (HNE), a peroxidation product of omega-6-polyunsaturated fatty acids. Furthermore, the growth modulating effect of serum factors, particularly albumin, on the growth pattern was examined. The effects of HNE on the growth rate and viability of the cells, as well as on the incorporation of labelled amino acids were monitored daily over a period of four days. Fetal calf serum not only had a growth stimualting effect but also modulated the action of HNE. In neither respect was albumin able to substitute for serum indicating that the influence of serum was not exerted via an albumin–HNE conjugate. HNE had a clear dose-dependent effect and a distinction could be made between a supraphysiological concentration (100 μM), which was primarily cytotoxic and a physiological range (below 10 μM) which showed growth modulatory effects. These effects consisted of a transient inhibition in the initial phase of the cell growth, which under optimal conditions (in presence of serum) was followed by a period of increased proliferation, compared to untreated control cultures, until confluence was attained. It is suggested that HNE is not only a toxic product of lipid peroxidation, but a physiological growth regulating factor as well. 相似文献
88.
Gregor Stiglic Petra Povalej Brzan Nino Fijacko Fei Wang Boris Delibasic Alexandros Kalousis Zoran Obradovic 《PloS one》2015,10(12)
Different studies have demonstrated the importance of comorbidities to better understand the origin and evolution of medical complications. This study focuses on improvement of the predictive model interpretability based on simple logical features representing comorbidities. We use group lasso based feature interaction discovery followed by a post-processing step, where simple logic terms are added. In the final step, we reduce the feature set by applying lasso logistic regression to obtain a compact set of non-zero coefficients that represent a more comprehensible predictive model. The effectiveness of the proposed approach was demonstrated on a pediatric hospital discharge dataset that was used to build a readmission risk estimation model. The evaluation of the proposed method demonstrates a reduction of the initial set of features in a regression model by 72%, with a slight improvement in the Area Under the ROC Curve metric from 0.763 (95% CI: 0.755–0.771) to 0.769 (95% CI: 0.761–0.777). Additionally, our results show improvement in comprehensibility of the final predictive model using simple comorbidity based terms for logistic regression. 相似文献
89.
Milan Ivanov Nevena Mihailovi?-Stanojevi? Jelica Gruji? Milanovi? ?ur?ica Jovovi? Jasmina Markovi?-Lipkovski Sanja ?irovi? Zoran Miloradovi? 《PloS one》2014,9(5)
Ischemic acute renal failure (ARF) is a highly complex disorder involving renal vasoconstriction, filtration failure, tubular obstruction, tubular backleak and generation of reactive oxygen species. Due to this complexity, the aim of our study was to explore effects of Angiotensin II type 1 receptor (AT1R) blockade on kidney structure and function, as well as oxidative stress in spontaneously hypertensive rats (SHR) after renal ischemia reperfusion injury. Experiments were performed on anaesthetized adult male SHR in the model of ARF with 40 minutes clamping the left renal artery. The right kidney was removed and 40 minutes renal ischemia was performed. Experimental groups received AT1R antagonist (Losartan) or vehicle (saline) in the femoral vein 5 minutes before, during and 175 minutes after the period of ischemia. Biochemical parameters were measured and kidney specimens were collected 24h after reperfusion. ARF significantly decreased creatinine and urea clearance, increased LDL and lipid peroxidation in plasma. Treatment with losartan induced a significant increase of creatinine and urea clearance, as well as HDL. Lipid peroxidation in plasma was decreased and catalase enzyme activity in erythrocytes was increased after losartan treatment. Losartan reduced cortico-medullary necrosis and tubular dilatation in the kidney. High expression of pro-apoptotic Bax protein in the injured kidney was downregulated after losartan treatment. Our results reveal that angiotensin II (via AT1R) mediates the most postischemic injuries in hypertensive kidney through oxidative stress enhancement. Therefore, blockade of AT1R may have beneficial effects in hypertensive patients who have developed ARF. 相似文献
90.
Mirjana Lenhardt Goran Markovic Aleksandar Hegedis Stevan Maletin Miroslav Cirkovic Zoran Markovic 《Reviews in Fish Biology and Fisheries》2011,21(3):407-421
A total of 22 fish species have been introduced into the inland waters of Serbia, either intentionally or accidentally. This
paper provides a summary of data concerning time and reason of introduction, mode of expansion, degree of acclimatization,
impact on native fish and estimated area of recent distribution. Four of the non-native fish species currently occupy more
than 51% of Serbian territory while 5 of them occupy between 21–50% of territory. This paper reviews impacts of introduced
freshwater fish in Serbia based on collected data. 相似文献