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1.
Prednisone-induced worsening of neuromuscular function in myasthenia gravis   总被引:2,自引:0,他引:2  
In patients with myasthenia gravis who received single doses of prednisone orally (40 to 100 mg), we found acute inhibition of neuromuscular function as manifest by increased decremental responses to repetitive nerve stimulation, reduced twitch tension, and lowered maximum voluntary contraction strength. The time course of these changes correlated with plasma methylprednisolone levels, implying direct drug effects on neuromuscular function.  相似文献   
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BACKGROUND AND AIMS: It is not known, to what extent the observed cellular changes in healing surgical wounds are species-, individual- or site-specific or whether they depend on the research method used. The aim of this study was to compare two independent methods for harvesting wound cells from porcine wounds after two time intervals, and to assess individual changes of wound cell composition. MATERIAL AND METHODS: In a standardised wound model in six pigs, with eight dorsal skin incision wounds in each, the Cellstick device and the Wound Edge Contact (WEC) method were used to collect inflammatory cells from the same wounds at hour 6 or 24 post-surgery. The wound cells were stained by the May-Grünwald-Giemsa (MGG) -method and counted differentially. RESULTS: A significant difference was found between the 6 and 24 hour Cellstick specimen in the proportions of wound neutrophils (p = 0.007), lymphocytes (p = 0.02) and monocytes (p < 0.001). The differential counts of wound cells within each individual animal did not significantly differ from each other. Instead, a significant difference was found in the wound neutrophils (p = 0.001), lymphocytes (p = 0.04) and monocytes (p < 0.001) between the wounds of individual animals. The WEC method revealed the same significant differences in the wound cell proportions. CONCLUSIONS: The Cellstick and the WEC method gave analogous results with equal variances from the incision wounds for up to at least 24 hours after injury.  相似文献   
4.
Absent response of serum thyrotrophin (TSH) after stimulation with 200 micrograms synthetic thyrotrophin-releasing hormone (TRH) was used as a criterion of adequate suppression of TSH in the treatment of thyroid carcinoma patients with thyroxine. The mean causing total suppression of the response was 223 micrograms of thyroxine per day. At this dose level about 40% of the patients had serum thyroxine concentrations above the upper reference interval and only 10% had elevated triiodothyronine concentrations. In some patients the TSH response to TRH varied between absent and low normal when tested at long intervals. The ideal dose of thyroxine is obviously slightly higher than the smallest one causing total suppression of the TSH response to TRH, i.e. about 250 micrograms a day. The individual dose must be found using the TRH stimulation test because serum thyroid hormone levels cannot be used as a guideline for adequate dosage. In some patients the thyroid remnant of apparently normal thyroid tissue was not totally suppressed although the thyroxine dose was definitely above the level causing suppression of the response to TRH.  相似文献   
5.

Background

Individual depressive symptoms may contribute to the risk of chronic depression. This study aimed to explore which symptoms predict chronic dysphoria, a hallmark of depression.

Methods

1057 participants from the population-based Young Finns study were examined for four times during a 16-year period. Those with a modified Beck’s Depression Inventory score in the upper third at all four screenings were considered to have chronic dysphoria (n=135). Participants with only one high depression score formed the reference group of transient dysphoria (n=179). Individual items of the Inventory were analyzed in terms of their association with dysphoria status and chronicity, controlling for potential confounding factors, such as personality assessed using the Temperament and Character Inventory.

Results

Body-image dissatisfaction was strongly associated with chronically elevated dysphoria (Bonferroni-corrected p=0.006). The degree of body-image dissatisfaction was associated with the probability for chronic dysphoria in a dose–response manner, with the estimated probability ranging from 0.01 to 0.60 as a function of item response. The association remained after adjustments for a wide range of personality characteristics.

Limitations

The study relied on self-reports of mood and personality, and lacked information on external opinion on participants appearances. The requirement of full time-series data may have resulted in attrition-related bias.

Conclusions

Body-image dissatisfaction was a strong predictor of chronic depression characterized by dysphoria. This finding suggests that dysfunctional attitude towards oneself might represent a potentially important target for cognitive therapies and preventive interventions.  相似文献   
6.
Metal phthalocyanines (MPcs) are a widely studied class of materials that are frequently used in organic thin-film transistors (OTFTs), organic photovoltaics (OPVs) and organic light emitting diodes (OLEDs). The stability of these devices and the materials used in their fabrication is important to realize their widespread adoption. Seven P-type MPcs: zinc (ZnPc), magnesium (MgPc), aluminum (AlClPc), iron (FePc), cobalt (CoPc), and titanium (TiOPc) were investigated as the semiconductors in OTFTs under varying temperatures (25 °C to 150 °C) and environmental conditions (air and vacuum, P < 0.1 Pa). Devices using the divalent MPcs (except MgPc) showed significant shifts in threshold voltage and field-effect mobility with rising temperature in both air and vacuum. AlClPc and TiOPc, on the other hand, had more stable electrical properties, making them useful for applications requiring consistent performance. Distinct variations in film morphology as determined by atomic force microscopy may explain the different thermal response between the two groups of MPcs, while thermal gravimetric analysis in air and nitrogen (N2) provides additional insight into their susceptibility to oxidation at elevated temperature. To demonstrate proof-of-concept thermal sensing under realistic operating conditions, current changes were monitored in response to temperature stimuli using two more sensitive divalent MPcs. This comparative study of the effect of central atom inclusion in MPcs, the resulting material stability and thin-film characteristics will facilitate design of future sensors and other OTFT applications.

A series of metal phthalocyanine based organic thin film transistors were evaluated and their responses to changes in temperature and environmental was determined: the choice of central atom makes a difference.  相似文献   
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8.
The UK islet allotransplant program is nationally funded to deliver one or two transplants over 12 months to individuals with type 1 diabetes and recurrent severe hypoglycemia. Analyses were undertaken 10 years after program inception to evaluate associations between transplanted mass; single versus two transplants; time between two transplants and graft survival (stimulated C-peptide >50 pmol/L) and function. In total, 84 islet transplant recipients were studied. Uninterrupted graft survival over 12 months was attained in 23 (68%) single and 47 (94%) (p = .002) two transplant recipients (separated by [median (IQR)] 6 (3–8) months). 64% recipients of one or two transplants with uninterrupted function at 12 months sustained graft function at 6 years. Total transplanted mass was associated with Mixed Meal Tolerance Test stimulated C-peptide at 12 months (p < .01). Despite 1.9-fold greater transplanted mass in recipients of two versus one islet infusion (12 218 [9291–15 417] vs. 6442 [5156–7639] IEQ/kg; p < .0001), stimulated C-peptide was not significantly higher. Shorter time between transplants was associated with greater insulin dose reduction at 12 months (beta ?0.35; p = .02). Graft survival over the first 12 months was greater in recipients of two versus one islet transplant in the UK program, although function at 1 and 6 years was comparable. Minimizing the interval between 2 islet infusions may maximize cumulative impact on graft function.  相似文献   
9.
We present a comprehensive review of the applications of biosynthesized metallic nanoparticles (NPs). The biosynthesis of metallic NPs is the subject of a number of recent reviews, which focus on the various “bottom-up” biofabrication methods and characterization of the final products. Numerous applications exploit the advantages of biosynthesis over chemical or physical NP syntheses, including lower capital and operating expenses, reduced environmental impacts, and superior biocompatibility and stability of the NP products. The key applications reviewed here include biomedical applications, especially antimicrobial applications, but also imaging applications, catalytic applications such as reduction of environmental contaminants, and electrochemical applications including sensing. The discussion of each application is augmented with a critical review of the potential for continued development.  相似文献   
10.

Background  

Novelty seeking temperament has been associated with higher coronary heart disease risk factors, but the mechanism behind the association is open. Cardiac stress response is a potential candidate.  相似文献   
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