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21.
One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the
amount of capsular contraction was found much less than when similar ``slick' prostheses were used. Another advance was their
fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were
moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of
the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been
that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced. 相似文献
22.
23.
建立了较完整的估计重油和沥青中饱和碳浓度数方法,其中包括环烷桥头碳、环烷甲基取代碳、环烷烷基(≥C2)取代碳等。基于理论分析,建立了估计环间的桥链和各种平均结构参数的方法,包括平均芳环环核数和环烷环环核数、芳环和环烷环烷工取代度、单元片上芳环和环烷环数。从实验数据出发,提出了烷基链长分布的公式。 相似文献
24.
J. A. Dunstan J. Roper L. Mitoulas† P. E. Hartmann† K. Simmer S. L. Prescott 《Clinical and experimental allergy》2004,34(8):1237-1242
BACKGROUND: Breast milk contains many immunomodulatory factors (soluble CD14 (sCD14), IgA and cytokines) with the potential to influence infant immune development. OBJECTIVE: To determine if changes in breast milk omega-3 polyunsaturated fatty acid (n-3 PUFA) composition as a result of maternal dietary fish oil supplementation during pregnancy can modify levels of these immunological parameters in breast milk. METHOD: In a randomized controlled trial, 83 atopic women received either 4 g fish oil capsules (containing 3.7 g n-3 PUFA) (n = 40) or 4 g olive oil capsules (n = 43) from 20 weeks gestation until delivery. Breast milk was collected 3 days post-partum and fatty acids were analysed by gas liquid chromatography and IgA, sCD14 and cytokines (IL-5, IL-6, IL-10, TNF-alpha and IFN-gamma) were quantitated by ELISA or time resolved fluorescence (TRF). RESULTS: Omega-3 docosahexaenoic acid (DHA; 22:6n-3) and eicosapentaenoic acid (EPA; 20:5n-3) levels were significantly higher (P < 0.001) in breast milk from women supplemented with fish oil (n = 33, DHA mean 1.15%, SD 0.47% and EPA mean 0.16%, SD 0.07%) than in samples from the control group (n = 40, DHA mean 0.50%, SD 0.17% and EPA mean 0.05%, SD 0.02%). Breast milk arachidonic acid (AA; 20:4n-6) levels were significantly lower (P = 0.045) in the fish oil group (mean 0.55%, SD 0.12%) compared with the control group (mean 0.61%, SD 0.14%). Breast milk IgA was positively correlated with DHA (P = 0.046) and 22:5n-3 (P = 0.003), but inversely correlated with linoleic acid (LA; 18:2n-6) (P=0.034). Levels of sCD14 were also positively correlated with 22:5n-3 (P=0.009). Cytokines involved in IgA synthesis (IL-10 and IL-6) were also significantly correlated with both IgA and n-3 PUFA levels, although there were no differences in the levels of breast milk IgA, sCD14 or cytokines between study groups. CONCLUSION: Supplementation with fish oil during pregnancy significantly alters early post-partum breast milk fatty acid composition. omega-3 PUFA levels were positively associated with IgA and sCD14 levels, suggesting a relationship between fatty acid status and mucosal immune function. 相似文献
25.
The present study investigated the phototoxic effect of bergamot oil and its photosensitive component, bergapten, on sunburn cell (SBC) production in guinea pig skin. The back skin was pretreated with bergamot oil or bergapten and exposed to monochromatic light under various conditions. After irradiation, skin specimens were excised, and histological sections were prepared. The number of sunburn cells in the interfollicular epidermis was counted. The SBC formation by bergamot oil or bergapten plus UVB radiation was the same as that without pretreatment with any photosensitizer. In contrast, a significant number of SBCs were induced by bergamot oil or bergapten plus UVA radiation, but no SBCs were found after the treatment with UVA alone. The result indicates that bergamot oil or bergapten was photosensitized by UVA irradiation. The SBCs were linearly increased in a UV-dose dependent manner. On the basis of the regression lines, an action spectrum and spectral peak for the photosensitizers plus UVA were obtained. The action spectrum for bergamot oil- and bergapten-induced SBC formation was in the ranges of 325–365 nm and 325–350 nm, and their spectral peaks were at 335–345 nm and 335–350 nm, respectively. The data are in good accordance with those estimated from skin erythema reactions. Therefore, counting SBCs is a very useful parameter for quantitative evaluation of phototoxicity. 相似文献
26.
A. J. Ferdous S. N. Islam M. Ahsan C. M. Hasan Z. U. Ahmed 《Phytotherapy research : PTR》1992,6(3):137-140
The antibacterial activity of the volatile oil of Nigella sativa seeds was studied against 37 isolates of Shigella dysenteriae 1, Shigella flexneri, Shigella sonnei and Shigella boydii and 10 strains of Vibrio cholerae and Escherichia coli. Most of the strains were clinically resistant to ampicillin, co-trimoxazole and tetracycline. All the strains tested showed promising sensitivity to the volatile oil. The minimum inhibitory concentration (MIC) of the volatile oil for Shigella, Vibrio and Escherichia strains tested was between 50–400 μg/mL. 相似文献
27.
Leoncio Garrido Bettina Pfleiderer Bruce G. Jenkins Carol A. Hulka Daniel B. Kopans 《Magnetic resonance in medicine》1994,31(3):328-330
Studies using magnetic resonance spectroscopy in human volunteers to evaluate their livers in vivo and to analyze their blood in vitro suggest that there are measurable amounts of silicon compounds in the blood of some women with implants and that there is migration of silicone to other organs such as the liver. 相似文献
28.
29.
Multicoil Dixon chemical species separation with an iterative least-squares estimation method. 总被引:1,自引:0,他引:1
Scott B Reeder Zhifei Wen Huanzhou Yu Angel R Pineda Garry E Gold Michael Markl Norbert J Pelc 《Magnetic resonance in medicine》2004,51(1):35-45
This work describes a new approach to multipoint Dixon fat-water separation that is amenable to pulse sequences that require short echo time (TE) increments, such as steady-state free precession (SSFP) and fast spin-echo (FSE) imaging. Using an iterative linear least-squares method that decomposes water and fat images from source images acquired at short TE increments, images with a high signal-to-noise ratio (SNR) and uniform separation of water and fat are obtained. This algorithm extends to multicoil reconstruction with minimal additional complexity. Examples of single- and multicoil fat-water decompositions are shown from source images acquired at both 1.5T and 3.0T. Examples in the knee, ankle, pelvis, abdomen, and heart are shown, using FSE, SSFP, and spoiled gradient-echo (SPGR) pulse sequences. The algorithm was applied to systems with multiple chemical species, and an example of water-fat-silicone separation is shown. An analysis of the noise performance of this method is described, and methods to improve noise performance through multicoil acquisition and field map smoothing are discussed. 相似文献
30.
目的探讨不同方法治疗压疮的临床效果。方法将65例患者计Ⅱ~Ⅲ度溃疡84处按基本条件相当原则随机分成A、B、C三组,A组21例28处,伤口采用清创冲洗后,给予康惠尔水胶体敷料;B组23例30处,伤口采用湿润烧伤膏;C组21例26处,清创冲洗后,给予自制凡士林油纱敷料外敷溃疡面处。结果B组愈合率最高,且平均显效时间和愈合时间均较A、C两组明显缩短,且A、B组明显高于C组。结论采用清创冲洗后用湿润烧伤膏是治疗压疮较好的方法之一。 相似文献