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21.
To find a promising drug carrier to suppress tumor using magnetic induction hyperthermia (MIH) and targeted therapy, two superparamagnetic iron oxide nanoparticles (SPIONs) coated with polyethylene glycol (PEG) and LyP-1, respectively, were prepared and compared. The particle size ranges of PEG-SPIONs and LyP-1-SPIONs were 10–15 nm, and 15–20 nm, respectively. In FTIR spectra, PEG-SPIONs and LyP-1-SPIONs had strong peaks between 575 and 1630 cm?1. Specifically, the PEG-SPIONs mainly has peaks in 581 and 1630 cm?1. The LyP-1-SPIONs mainly had peaks in 575, 1050 and 1625 cm?1. The contents of Fe3O4 in the PEG-SPIONs and LyP-1-SPIONs were about 94.24 and 89.26%, respectively. The iron contents in the MCF-7 and CT-26 cells were 33.1 ± 1.8 and 27.9 ± 0.95 pg, respectively, after co-incubation with LyP-1-SPIONs for 8 h. The LyP-1-SPIONs accumulated in the nucleus of MCF-7 cells while PEG-SPIONs in cytoplasma. In vitro, after 30 days we can found the tumor almost stopped to grow in Group LyP-1-SPIONs. LyP-1-SPIONs are promising in treating cancer as they accumulated in the nucleus of MCF-7 cells which expressed p32 and almost stopped tumor growth by combined MIH and targeted therapy.  相似文献   
22.
Infective endocarditis (IE) is a life-threatening disease, caused by septic vegetations and inflammatory foci on the surface of the endothelium and the valves. Due to its complex and often indecisive presentation the mortality rate is still about 30%. Most frequently bacterial microorganisms entering the bloodstream are the underlying origin of the intracardiac infection. While the disease was primarily restricted to younger patients suffering from rheumatic heart streptococci infections, new at risk categories for Staphylococcus (S.) aureus infections arose over the last years. Rising patient age, increasing drug resistance, intensive treatment conditions such as renal hemodialysis, immunosuppression and long term indwelling central venous catheters but also the application of modern cardiac device implants and valve prosthesis have led to emerging incidences of S. aureus IE in health care settings and community. The aetiologic change has impact on the pathophysiology of IE, the clinical presentation and the overall patient management. Despite intensive research on appropriate in vitro and in vivo models of IE and gained knowledge about the fundamental mechanisms in the formation of bacterial vegetations and extracardiac complications, improved understanding of relevant bacterial virulence factors and triggered host immune responses is required to help developing novel antipathogenic treatment strategies and pathogen specific diagnostic markers.In this review, we summarize and discuss the two main areas affected by the changing patient demographics and provide first, recent knowledge about the pathogenic strategies of S. aureus in the induction of IE, including available experimental models of IE used to study host-pathogen interactions and diagnostic and therapeutic targets. In a second focus we present diagnostic (imaging) regimens for patients with S. aureus IE according to current guidelines as well as treatment strategies and surgical recommendations.  相似文献   
23.

Purpose

To compare diameters of in vivo microwave ablation (MWA) performed in swine kidneys with ex vivo diameters, and to correlate with ablation work (AW), a new metric reflecting total energy delivered.

Material and methods

Eighteen in vivo MWA were performed in 6 swine kidneys successively using one or two antennas (MicroThermX®). Ablation consisted in delivering power (45–120 W) for 5–15 minutes. Ex vivo diameters were provided by the vendors and obtained on bovine liver tissue. AW was defined as the sum of (power)*(time)*(number of antennas) for all phases of an ablation (in kJoules). Kidneys were removed laparoscopically immediately after ablation. After sacrifice, ablations zones were evaluated macroscopically, and maximum diameters of the zones were recorded. Wilcoxon sum rank test and Pearson's correlation were used for comparisons.

Results

For a single antenna (n = 12), the in vivo diameters ranged from 12 to 35 mm, and 15–49 mm for 2 antennas (n = 6). The in vivo diameters remained shorter than ex vivo diameters by 8.6% ± 30.1 on 1 antenna and 11.7% ± 26.5 on 2 antennas (P = 0.31 and 0.44, respectively). AW ranged from 13.5 to 108 kJ. Diameters increased linearly with AW both with 1 and 2 antennas, but only moderate correlations were observed (r = 0.43 [95% confidence interval: ?0.19; 0.81], P = 0.16; and 0.57 [?0.44; 0.95], P = 0.24, respectively).

Conclusion

Although diameters after in vivo renal MWA increased linearly with AW, the moderate correlation and wide standard deviations observed may justify a careful imaging monitoring during treatment delivery and settings adaptation, if needed, for optimal ablation.  相似文献   
24.
25.
Stiff skin syndrome is a rare genetic disorder that is present in infancy or early childhood. It is characterized by hard, inflexible skin and limited joint mobility making anesthetic management of these patients challenging. Their limited neck flexibility and chest wall rigidity make intubation and mask ventilation difficult. Intraoperative positioning can be challenging due to joint contractures and potential entrapment peripheral neuropathy. Even though peripheral intravenous access can be relatively easy, central venous cannulation may be problematic due to the hard skin overlying the entry sites. Our case report details the anesthetic management and considerations of a pediatric patient with stiff skin syndrome.  相似文献   
26.
In 14 patients (12 men, 2 women, mean age 51 +/- 4 years) we evaluated a new technique for intraoperative arrhythmia induction during Ventak 1550 automatic implantable cardioverter defibrillator (AICD), pulse generator placement. At the time of surgery (nine new implants, five pulse generator replacements), when the AICD pulse generator is in its final configuration with the rate sensing and patch electrodes leads inserted into the header, a #2 hex wrench was inserted into each of the rate sensing lead set screw sites. The alligator clips of a temporary pacing cable were placed on each of the hex wrenches and the remainder of the cable passed off field for attachment to a programmed stimulator or AC fibrillator. In all 14 patients, the clinical arrhythmia was induced at least twice (ventricular tachycardia in eight patients, ventricular fibrillation in six patients). No difficulties with arrhythmia induction or AICD sensing as discharge were encountered. We conclude that this technique is both a safe and effective means of intraoperative arrhythmia induction during placement or replacement in the Ventak AICD 1550 and 1600 series pulse generators.  相似文献   
27.
Neddermeyer TJ  Flühr K  Lötsch J 《Pain》2008,138(2):286-291
We addressed the question whether pain thresholds to different stimuli measure independent aspects of pain or one common phenomenon. In the first case, different stimuli are required to completely characterize a subject’s pain sensitivity. In the second case, different stimuli are redundant and can be used to calculate composite scores across pain modalities. We measured pain thresholds to several stimuli (heat, heat/capsaicin, cold, cold/menthol, blunt pressure, 5-Hz sine-wave electric current (0–20 mA), punctate pressure (von Frey hairs), and von Frey hairs plus capsaicin application) in 45 healthy men and 32 healthy women (aged 20–44 years). We observed that pain thresholds were significantly correlated with each other. Principal component analysis indicated that their variance was attributable more to the difference in subjects (variance estimate: 0.393) than to the difference in pain stimuli within a subject (variance estimate: −0.008). Among three principal components of the intercorrelation matrix with eigenvalues >1, the first, explaining 48% of the total variance, carried high loadings from all stimuli indicating that they shared a common source of half of their variance. Only minor variance components, each explaining <14% of the total variance, indicated a distinction of pain stimuli. There, a pattern of similarities and dissimilarities emerged agreeing with known distinct mechanisms of nociceptive responses to different stimuli. We conclude that characterizing a person as being generally stoical or complaining to any painful stimulus appears to be justified at least at pain threshold level.  相似文献   
28.

Objectives

To evaluate the precision and accuracy in CT attenuation measurement of vascular wall using region-of-interest (ROI) supported by differentiation curves.

Study design

We used vascular models (actual attenuation value of the wall: 87 HU) with wall thicknesses of 1.5, 1.0, or 0.5 mm, filled with contrast material of 250, 348, or 436 HU. The nine vascular models were scanned with a 64-detector CT. The wall attenuation values were measured using three sizes (diameter: 0.5, 1.0, and 1.5 mm) of ROIs without differentiation curves. Sixteen measurements were repeated for each vascular model by each of two operators. Measurements supported by differentiation curves were also performed. We used analyses of variance with repeated measures for the measured attenuations for each size of the ROI.

Results

Without differentiation curves, there were significant differences in the attenuation values of the wall among the three densities of contrast material, and the attenuation values tended to be overestimated more as the contrast material density increased. Operator dependencies were also found in measurements for 0.5- and 1.5-mm thickness models. With differentiation curves, measurements were not possible for 0.5- and 1.0-mm thickness models. Using differentiation curves for 1.5-mm thickness models with a ROI of 1.0- or 1.5-mm diameter, the wall attenuations were not affected by the contrast material densities and were operator independent, measuring between 75 and 103 HU.

Conclusions

The use of differentiation curves can improve the precision and accuracy in wall attenuation measurement using a ROI technique, while measurements for walls of ≤1.0 mm thickness are difficult.  相似文献   
29.
Two commercially available methods of total serum IgE determination have been evaluated, viz: the radioimmunosorbent test (RIST) and the assay by single radial immunodiffusion (RID). RIST was found a suitable and rapid method for the wide range of IgE concentrations to be expected in the sera of an allergic population. The RID method has a lower limit of detection of about 1000 I.U./ml; over this value, both techniques provided statistically correlated results. However, for technological reasons RID was considered less suitable for routine application.  相似文献   
30.
Abstract:   While sex differences in pain reporting are frequently observed, the reasons underlying these differences remain unclear. The present study examined sex differences in self-report and physiological measures of pain threshold and tolerance following the administration of two laboratory pain-induction tasks. The primary study aim centered on determining whether repeated exposure to such tasks would yield sex differences in terms of pain threshold and tolerance. In addition, it was hypothesized that if such differences did exist, negative mood states might account for changes in pain ratings, threshold, and/or tolerance in subsequent exposure to noxious stimuli. Recruited from a convenience sample, 66 participants (44 female and 22 male) were exposed to both thermal and cold noxious stimuli at three separate times, while psychophysiological and self-report data were collected. Because women outnumbered men 2:1, Fisher z transformations were performed to determine whether the observed associations between mood states and pain ratings differed. We found stronger associations between fatigue and thermal-heat pain ratings for men at their first and third exposure to the pain task compared to women ( z  = 2.11, P  < 0.05; z  = 3.14, P  < 0.001, respectively). Results indicated that women evidenced greater pain tolerance than men on both a behavioral and physiological level; however, they reported greater pain severity than men. Fatigue was also found to be particularly important to reports of pain severity in men and pain tolerance in response to noxious stimuli for women. Possible pathways in which mood states influenced these endpoints are discussed.  相似文献   
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