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排序方式: 共有654条查询结果,搜索用时 15 毫秒
61.
The report presents two cases of neurofibromatosis type 1 one previously known and one detected during pregnancy. It describes how the disease was detected and diagnosed, and what was the outcome of pregnancies. This is the first case of prenatal neurofibromatosis type 1 diagnosed in our clinic.  相似文献   
62.
63.
Reich BJ  Hodges JS  Zadnik V 《Biometrics》2006,62(4):1197-1206
Disease-mapping models for areal data often have fixed effects to measure the effect of spatially varying covariates and random effects with a conditionally autoregressive (CAR) prior to account for spatial clustering. In such spatial regressions, the objective may be to estimate the fixed effects while accounting for the spatial correlation. But adding the CAR random effects can cause large changes in the posterior mean and variance of fixed effects compared to the nonspatial regression model. This article explores the impact of adding spatial random effects on fixed effect estimates and posterior variance. Diagnostics are proposed to measure posterior variance inflation from collinearity between the fixed effect covariates and the CAR random effects and to measure each region's influence on the change in the fixed effect's estimates by adding the CAR random effects. A new model that alleviates the collinearity between the fixed effect covariates and the CAR random effects is developed and extensions of these methods to point-referenced data models are discussed.  相似文献   
64.
The aim of this work was to investigate the influence of [PdCl4]2-, [PdCl(dien)]+ and [PdCl(Me4dien)]+ complexes on Na+ / K+-ATPase activity. The dose-dependent inhibition curves were obtained in all cases. IC50 values determined by Hill analysis were 2.25 x 10(-5) M, 1.21 x 10(-4) M and 2.36 x 10(-4) M, respectively. Na+ / K+-ATPase exhibited typical Michelis-Menten kinetics in the presence of Pd(II) complexes. Kinetic parameters (Vmax, Km) derived using Eadie-Hofstee transformation indicated a noncompetitive type of Na+ / K+-ATPase inhibition. The inhibitor constants (Ki) were determined from Dixon plots. The order of complex affinity for binding with Na+ / K+-ATPase, deducted from Ki values, was [PdCl4]2- > [PdCl(dien)]+ > [PdCl(Me4dien)]+. The results indicated that the potency of Pd(II) complexes to inhibit Na+/ K +-ATPase activity depended strongly on ligands of the related compound. Furthermore, the ability of SH-donor ligands, L-cysteine and glutathione, to prevent and recover the Pd(II) complexes-induced inhibition of Na+ / K+-ATPase was examined. The addition of 1 mM L-cysteine or glutathione to the reaction mixture before exposure to Pd(II) complexes prevented the inhibition by increasing the IC50 values by one order of magnitude. Moreover, the inhibited enzymatic activity was recovered by addition of SH-donor ligands in a concentration-dependent manner.  相似文献   
65.
The aim of this study was to examine the association of weight gain and life expectancy at birth in Croatia. Mean body mass index was based on the data from the Croatian Adult Health Survey 2003. Birth rate and mortality data needed for life expectancy calculation were supplied by the Central Bureau of Statistics. The results suggest that the increase in mean body mass index value (1.31 kg m(-2) for women and 1.41 kg m(-2) for men) will shorten life expectancy at birth for one year. Obesity, if unchecked, might have a negative effect on life expectancy in Croatia. Despite widespread knowledge about how to reduce the severity of the problem, observed trends in obesity in Croatia continue to worsen. These trends threaten to diminish the health and life expectancy of current and future generations.  相似文献   
66.
This study was undertaken to examine the alteration of masseter and plasma interleukin-6 after inducing occlusal interference and chronic stress. Male Wistar rats were submitted to chronic stress procedure, exposed to occlusal interference, or exposed to both mentioned procedures. Whole blood and masseter tissue were collected to determine interleukin-6 level, measured by means of ELISA. Masseter pain was evaluated using the orofacial formalin test. Masseter interleukin-6 level was significantly higher in animals submitted to combination of occlusal interference and chronic stress than in the control group (p<0.05). There was positive and significant correlation between pain response and masseter interleukin-6 level (r=0.5741; p<0.0003). No significant differences in plasma interleukin-6 level were found between groups (p>0.05), as well as no correlation with pain (p>0.05). Combination of occlusal interference and chronic stress leads to strong local reaction characterized by high levels of masseter interleukine-6. High concentrations of muscle interleukin-6 and its correlation with pain point to inflammatory background of masticatory muscle pain.  相似文献   
67.
The objective of this paper was to evaluate the 5-year incidence of obesity on a sample of 3229 adults and investigate the potential effect of several sociodemographic and lifestyle habits on weight change and obesity incidence in these individuals. The average annual rate of increase in the prevalence of obese adults between 2003 and 2008 was 10.60% for men and 11.08% for women. Analysis showed that development of obesity in 5-year period in women in Croatia is significantly positively associated with frequent consumption of "hidden" fats of animal origin and significantly negative with each higher education level. No significant predictor of obesity has been found in men. Obesity remains a serious health problem for the Croatian population; the alarming rates of excess body weight continue to increase. Preventive measures should urgently be undertaken.  相似文献   
68.
During the eighteen-year period in "Sestre milosrdnice" University Hospital Center, Zagreb, 271 women with ovarian tumor was studied. 229 women with ovarian cancer and 42 with borderline tumor. The pathohistological types of tumors were different. The age of the patients ranged from 20-83 years. In all patients the value of biochemical marker CA125 was determined. The aim of this study was to determine the usefulness of CA125 measurement in different age groups and in different patohistologycal forms of tumor. CA125 has proven to be positive in 89.1% of women with ovarian cancer and in 62% with neoplasm of low malignant potential. The higher values of CA125 were detected in younger women with low malignant tumor potential. Serous and metastatic tumor types were also associated with higher values of CA125.  相似文献   
69.
Human Jagged-1, one of the ligands of Notch receptors, is a transmembrane protein composed of a large extracellular region and a 125-residue cytoplasmic tail which bears a C-terminal PDZ recognition motif. To investigate the interaction between Jagged-1 cytoplasmic tail and the inner leaflet of the plasma membrane we determined, by solution NMR, the secondary structure and dynamics of the recombinant protein corresponding to the intracellular region of Jagged-1, J1_tmic, bound to negatively charged lysophospholipid micelles. NMR showed that the PDZ binding motif is preceded by four α-helical segments and that, despite the extensive interaction between J1_tmic and the micelle, the PDZ binding motif remains highly flexible. Binding of J1_tmic to negatively charged, but not to zwitterionic vesicles, was confirmed by surface plasmon resonance. To study the PDZ binding region in more detail, we prepared a peptide corresponding to the last 24 residues of Jagged-1, J1C24, and different phosphorylated variants of it. J1C24 displays a marked helical propensity and undergoes a coil-helix transition in the presence of negatively charged, but not zwitterionic, lysophospholipid micelles. Phosphorylation at different positions drastically decreases the helical propensity of the peptides and abolishes the coil-helix transition triggered by lysophospholipid micelles. We propose that phosphorylation of residues upstream of the PDZ binding motif may shift the equilibrium from an ordered, membrane-bound, interfacial form of Jagged-1 C-terminal region to a more disordered form with an increased accessibility of the PDZ recognition motif, thus playing an indirect role in the interaction between Jagged-1 and the PDZ-containing target protein.  相似文献   
70.
General adhesion behavior of phospholipid vesicles was examined in a wide range of potentials at the mercury electrode by recording time-resolved adhesion signals. It was demonstrated that adhesion-based detection is sensitive to polar headgroups in phospholipid vesicles. We identified a narrow potential window around the point of zero charge of the electrode where the interaction of polar headgroups of phosphatidylcholine vesicles with the substrate is manifested in the form of bidirectional signals. The bidirectional signal is composed of the charge flow due to the nonspecific interaction of vesicle adhesion and spreading and of the charge flow due to a specific interaction of the negatively charged electrode and the most exposed positively charged choline headgroups. These signals are expected to appear only when the electrode surface charge density is less than the surface charge density of the choline groups at the contact interface. In comparison, for the negatively charged phosphatidylserine vesicles, we identified the potential window at the mercury electrode where charge compensation takes place, and bidirectional signals were not detected.  相似文献   
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