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31.
El-Shazly MM El-Sonbaty MA Kamel AH Zaki MS Baumeister RG 《Plastic and reconstructive surgery》2004,113(1):294-298
Microsurgery is one of the highly interesting surgical procedures that can be performed using different applications and in different specialties, including plastic surgery. The endoscope is a popular instrument used in many fields, including plastic surgery. Although the operating microscope is still a must for microsurgical performance, microsurgery could be performed, depending on the experiences and facilities, by using other visual-assisting equipment. From this point of view, the authors tried to find less costly and more widespread equipment suitable for performing microsurgery that can, furthermore, be applied in special situations and indications, such as operating in an optical cavity. The authors investigated this issue with the endoscope. In this experimental project, the authors performed vascular microsurgical anastomoses of the rats' femoral vessels to create an optical cavity in a prefabricated skin retraction model in the groin area of 10 Sprague-Dawley male rats. The microsurgical anastomoses of the femoral vessels and nerves were performed easily in a reasonable time, without recorded difficulties, and with maximum physical and visual comfort for the surgeon. The authors spent a mean time of 28.1, 27.3, and 19.2 minutes for the arterial, venous, and neural anastomoses, respectively. In this group of animals, 90 percent vascular patency and 100 percent accurate neural anastomoses were recorded. The advantage the authors noted was that this new technique of operating in the field of microsurgery, with its feasibility and difficulties, would be a point of research and application for the young generations of microsurgeons. 相似文献
32.
Houman H Hamzaoui A Ben Ghorbal I Khanfir MS Feki M Hamzaoui K 《Mediators of inflammation》2004,13(4):247-253
BACKGROUND: Peripheral blood CD8+ T cells expressing interferon gamma and interleukin-4 (IL-4), and lacking CD28 molecules, were responsible for the dynamic interplay between peripheral blood and inflammatory sites. INTRODUCTION: The aim of the current study was to define in Behçet''s disease (BD), CD8+ T-cell subsets using CD28 and CD11b monoclonal antibodies, and the characterization of the Tc1/Tc2 ratio and perforin expression. METHODS: Flow cytometry was used for intracytoplasmic cytokines and perforin expression. Effector cells were investigated by adhesion of CD8+ T cells to human microvascular endothelial cells and by chemotaxis using beta-chemokine. RESULTS: Interferon-gamma-producing CD8+ T cells in active and remission BD patients were increased, which induce a significant increase of the Tc1:Tc2 ratio in BD. CD8(+)CD28(-)CD11b+ T cells were found to be more expanded in BD patients than in age-matched healthy controls. The expression of CD11b molecules in active BD allowed to CD8(+)CD28+/CD8(+)CD28- subsets to adhere to human microvascular endothelial cells, with more efficiency in BD. Using MIP-1alpha, we observed that the migratory process of CD28(-)CD11b(+) is more important in BD. CD28(-)CD11b+ exhibited an increased perforin expression in BD patients. CONCLUSION: Taken together these results suggest the presence of immune activation, probably in response to a profound inflammation affecting BD patients. The physiopathological significance of these results were toward autoimmune diseases and/or infectious process. 相似文献
33.
Cantu C Benlagha K Savage PB Bendelac A Teyton L 《Journal of immunology (Baltimore, Md. : 1950)》2003,170(9):4673-4682
CD1 resembles both class I and class II MHC but differs by the important aspect of presenting lipid/glycolipids, instead of peptides, to T cells. Biophysical studies of lipid/CD1 interactions have been limited, and kinetics of binding are in contradiction with functional studies. We have revisited this issue by designing new assays to examine the loading of CD1 with lipids. As expected for hydrophobic interactions, binding affinity was not high and had limited specificity. Lipid critical micelle concentration set the limitation to these studies. Once loaded onto CD1d, the recognition of glycolipids by alphabeta T cell receptor was studied by surface plasmon resonance using soluble Valpha14-Vbeta8.2 T cell receptors. The Valpha14 Jalpha18 chain could be paired with NK1.1 cell-derived Vbeta chain, or any Vbeta8 chain, to achieve high affinity recognition of alpha-galactosylceramide. Biophysical analysis indicated little effect of temperature or ionic strength on the binding interaction, in contrast to what has been seen in peptide/MHC-TCR studies. This suggests that there is less accommodation made by this TCR in recognizing alpha-galactosylceramide, and it can be assumed that the most rigid part of the Ag, the sugar moiety, is critical in the interaction. 相似文献
34.
Cohen RI Hassell AM Ye X Marzouk K Liu SF 《Biochemical and biophysical research communications》2003,307(3):451-458
Studies of the regulation of iNOS expression have provided many contradictory results. Comparing iNOS expression profile between cell types or organs of the same animal under the same experimental conditions may provide an explanation for these conflicting results. We have examined iNOS mRNA and protein expression in heart and liver of the same group of pigs. We found that there is a sharp difference in iNOS expression between heart and liver. The iNOS mRNA and protein was constitutively expressed in the heart at high level, but was not detectable in the liver of the same control animal. Lipopolysaccharide (LPS, 100 microg/kg, i.v.) caused a marked iNOS induction in the liver, but significantly down-regulated iNOS expression in the heart. This differential iNOS expression appears to be physiologically relevant, since LPS and the iNOS inhibitor, S-methylisothiourea, exerted different effects on hepatic and myocardial blood flow. Our data demonstrate a fundamental difference in iNOS regulation in the heart and liver of swine, and may explain the contradictory data on the regulation of iNOS expression. 相似文献
35.
Iodine deficiency (ID) and related disorders are still major, yet unresolved health concerns. Recently, in a systematic survey
of schoolage children (SAC), we reported severe to moderate ID, in Ankara and three cities from Black Sea region of Turkey.
The current study attempted to evaluate selenium (Se) status, thiocyanate (SCN−) overload, and their possible contribution to the goiter endemics and thyroid hormone profile observed in these cities. Thyroid
ultrasonography was performed and serum Se, SCN−, thyroid hormones, sensitive TSH (sTSH) levels, and urinary iodine concentrations (UICs) were determined from 251 SAC (9–11
yr old).
Thyroid volumes (TVs) exceeding recommended upper normal limits and median UIC indicated goitre endemics and moderate to severe
ID in the areas studied. Mean serum SCN− concentrations were found to be greater than the controls from the literature. The UIC/SCN− ratio was found to be lowest in Bayburt and Trabzon denoting that SCN− overload may contribute to the goiter endemics. Serum Se concentrations represent a marginal deficiency in the four areas
studied. No significant correlations between serum Se concentrations and the other parameters studied (i.e., TV, SCN−, thyroid hormones, sTSH, UIC) was detected.
In conclusion, this study showed that selenium is also marginally deficient in the iodine-deficient endemic areas studied,
but this has little or no impact on the thyroid hormone profile and the goiter endemics. SCN− overload may contribute to the endemics, especially for the areas where iodine is severely deficient. An effective iodine
supplementation program will not only resolve the goiter endemics but also the consequence of SCN− overload as well in the endemic goiter areas studied. 相似文献
36.
Kamel MS 《Phytochemistry》2003,62(8):1247-1250
From the aerial parts of Solenostemma argel, four new acylated phenolic glycosides sinapyl alcohol 9-O-feruloyl-4-O-alpha-rhamnopyranosyl-(1-->2)-beta-glucopyranoside, solargin I (1), sinapyl alcohol 9-O-caffeoyl-4-O-alpha-rhamnopyranosyl-(1-->2)-beta-glucopyranoside, solargin II (2), sinapyl alcohol 9-O-feruloyl-4-O-alpha-rhamnopyranosyl-(1-->2)-alpha-rhamnopyranosyl-(1-->2)-beta-glucopyranoside, solargin III (3) and sinapyl alcohol 9-O-caffeoyl-4-O-alpha-rhamnopyranosyl-(1-->2)-alpha-rhamnopyranosyl-(1-->2)-beta-glucopyranoside, solargin IV (4) have been isolated. The structures of the isolated compounds were verified by means of MS and NMR spectral analyses. 相似文献
37.
Kamel MS 《Phytochemistry》2003,63(4):449-452
From the aerial parts of Lupinus hartwegii, two new flavone C-glycosides apigenin-7-O-beta-apiofuranosyl-6, 8-di-C-beta-glucopyranoside (1) and apigenin-7-O-beta-apiofuranosyl-6-C-beta-glucopyranosyl-8-C-(6z.qprime;-O-E-feruloyl)- beta-glucopyranoside (2) have been isolated together with two known isoflavonoid glucosides genistein-7-O-beta-glucopyranoside (3) and genistein-7, 4'-di-O-beta-glucopyranoside (4) as well as two known compounds ferulic acid 4-O-beta-glucopyranoside (5) and sparteine (6). The structures of the isolated compounds were verified by means of MS and NMR spectral analyses. 相似文献
38.
Mahmoud KZ Edens FW Eisen EJ Havenstein GB 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2003,136(4):329-335
Dietary ascorbic acid (AA) and heat stress (HS) affect heat shock protein 70 (hsp70) and body temperature (BT) of strain cross white Leghorn chickens. At five weeks of age, chicks fed either no supplemental AA (N-AA) or 200 mg/kg AA (AA) were subjected to either HS (42 degrees C) or maintained in control (CN, 23 degrees C) ambient temperature (T(a)) for 1 h. Body temperature (BT) was recorded for each bird before collection of heart and liver for hsp70 assay. In the CN AA-fed groups, neither the lower constitutive hsc70 nor the decreased hsp70 response to HS in the heart and liver were sex-dependent. The BT was increased by HS, but neither AA nor sex of the bird affected BT response. A diet X T(a) interaction revealed that BT of CN AA-fed chickens was lower than in N-AA-fed chickens, but BT of HS AA-fed chicks was greater than BT in HS N-AA-fed chickens. The BT and hsp70 responses were positively correlated. A lower expression of hsp70 indicated less of a stress response in the AA-fed chickens. 相似文献
39.
Minor phenolics from Crinum bulbispermum bulbs 总被引:1,自引:0,他引:1
From the bulbs of Crinum bulbispermum Milne, four new minor compounds were isolated viz. 4-hydroxy-2',4'-dimethoxydihydrochalcone (1), 4,5-methylenedioxy-4'-hydroxy-2-aldehyde[1,1'-biphenyl] (4), hippacine (6), and 4'-hydroxy-7-methoxyflavan-3-ol (7). In addition, four known compounds were isolated and identified as 2(S),3',4'-dihydroxy-7-methoxy flavan (2), isolarrien (3), isoliquiritigenin (5) and liquiritigenin (8). The structures of the isolated compounds were established by spectral evidence. 相似文献
40.
The effect of diethyl pyrocarbonate on chromatophores and isolated pigment--protein complexes of Chromatium minutissimum was studied. It is shown that modification of histidine residues results in the destruction of the core antenna LHI (B880) and in a spectral shift from 850 to 830 nm in the peripheral antenna LHII (B800-850). In the purple sulfur bacterium Chromatium minutissimum the pigment--protein complexes B800-B850 (peripheral antenna, LHII) and B880 (core antenna, LHI) collect and transmit the absorbed light energy to the reaction centers. The composition of pigments and proteins as well as primary structure of the majority of polypeptides in both types of complexes from various photosynthetic bacteria have been determined. 相似文献