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991.
992.
Arthroscopic surgery causes considerably less soft tissue damage than conventional surgery. As the result of the development of an optical system employed with a chip camera and a video chain arthroscopic knee surgery can be ideally documented with excellent picture quality. Besides the advantage of soft-tissue sparing procedures, diagnosis is substantially improved and operative procedures can be kept to a minimum. This means, in particular in the case of meniscus procedures, that only the damaged areas are removed, this minimising changes to the biomechanics of the knee. The technical equipment, the arthroscopic surgery technic and the advantages of the knee arthroscopy are discussed. 相似文献
993.
7-Deoxy-7-iodohept-1-enitols react intramolecularly to give 5-carba analogues of pyranoses (pseudo sugars) by the action of tributyltin hydride, which generates a radical at C-7. The configuration at the new chiral centre depends on the relative orientation of the oxygen functions in the starting material and the pattern of substitution. 相似文献
994.
H Carlsten N Nilsson R Jonsson K B?ckman R Holmdahl A Tarkowski 《Cellular immunology》1992,144(1):190-202
Estrogen is known to influence immune responses in healthy subjects in a dichotomous fashion. Thus, in number of previous studies we and others have demonstrated that B cell activities are augmented after exposure to estrogen whereas T cell reactivity is suppressed. Furthermore, it has been shown that this hormone has significant impact on the course of certain human and experimental autoimmune diseases. In this study we report that treatment with physiological doses of estradiol exerts dichotomous effects on different manifestations of the lupus disease in MRL/l mice. On one hand immune complex-mediated glomerulonephritis was significantly accelerated. This outcome was due to polyclonal B cell activation with increased production of antibodies to double-stranded DNA and formation of circulating immune complexes. In contrast, T cell-mediated lesions such as focal sialadenitis, renal vasculitis, and periarticular inflammation were all significantly ameliorated in MRL/l mice exposed to estrogen. Thus, we were able to demonstrate that, within one subject and even within one organ, administration of estrogen leads to differential outcome of SLE morbidity. We propose that the differential effect of estrogen on the manifestations of the autoimmune disease of MRL/l mice is due to its dichotomous effects on B and T cell-mediated immune responses. 相似文献
995.
K Fukuzawa W Ikebata A Shibata I Kumadaki T Sakanaka S Urano 《Chemistry and physics of lipids》1992,63(1-2):69-75
Studies were made on the position and dynamics of the OH-group of alpha-tocopherol in phospholipid membranes. There was no difference in the spin-lattice (T1) relaxation times at the 5a-position of alpha-tocopherol labeled with 13C- or C19F3-determined from the nuclear magnetic resonance (NMR) spectra of liposomes positively charged with stearylamine (SA) and negatively charged with dicetylphosphate (DCP). The zeta-potentials of egg yolk phosphatidylcholine (EYPC) liposomes with and without SA or DCP were not affected by incorporation of 20 mol% alpha-tocopherol, though incorporation of 10 mol% ascorbyl-palmitate decreased the zeta-potentials of EYPC and EYPC-SA liposomes. The P==O stretching band (1235 cm-1) of the phosphate group and C==O stretching band (1734 cm-1) of the acyl ester linkage in dimyristoylphosphatidylcholine (DMPC) liposomes, measured by Fourier transform-infrared (FT-IR) spectroscopy, were not changed by incorporation of alpha-tocopherol. These results suggest that no specific interaction occurred between the OH-group of alpha-tocopherol and the polar interfacial region of the bilayer. The dynamic quenching effects of n-(N-oxy-4,4'-dimethyloxazolidine-2-yl)stearic acids (n-NSs) on the intrinsic fluorescence of alpha-tocopherol were in the order 5-NS > 7-NS = 12-NS > 16-NS. Acrylamide, a water-soluble fluorescence quencher with a very low capacity to penetrate through phospholipid bilayers, had very low quenching efficiency. These results indicate that the bulk of the chromanol moiety of alpha-tocopherol is located in a position close to that occupied by the nitroxide group of 5-NS in the membranes and is poorly exposed at the membrane surface.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
997.
The effects of 2 redox based carriers for brain directed delivery of estradiol (CDS-E2) and ethinyl estradiol (CDS-EE) on body weight were examined in rats. A single dose of CDS-E2 (3 mg/kg) decreased weight gain in castrate rats for at least 24 days. The dose response of weight gain and LH suppression were compared 12 days and 12 to 25 after CDS-E2 and CDS-EE, respectively, in ovariectomized (OVX) rats. Weight decrease was detected at a lower dose and was significant for longer after drug treatment than LH decrease. Both compounds were more potent than equimolar estradiol or estradiol valerate in reducing weight gain. Intact rats also showed decreased weight gain but were less sensitive to CDS-E2 compared to OVX rats. The effects appeared to be estrogen specific as carrier-linked testosterone had no effect on weight. The mechanisms of sustained and potent drug effects on weight are being explored. 相似文献
998.
Summary The child with iminoglycinuria is in our observation. Hyperprolinuria was seen at 5 months by screening program. The child was repeatedly examined in the hospital and was seen last time at 16 months. IQ was 67, in the urine were excessive amounts of glycine, proline a hydroxyproline. In the blood aminoacids were in normal levels. In the child was noticed the same increase of proline in the blood as in the control child of the same age following loading test with L-proline, indicating normal intestinal absoption. Both parents and father's sister's 2-year-old mentally retarded child exhibit excessive glycinuria. The father, his sister, father's father, and grandfather are partialy, congenitaly deaf. 相似文献
999.
David W. Thomas Amabile K. Matida Célio L. Silva Thuioshi Ioneda 《Chemistry and physics of lipids》1979,23(3):267-282
The purification procedure of 6,6′-diesters of trehalose from Corynebacterium diphtheriae was modified and the isolated substance was analysed by mass spectrometry as its permethylated derivative. The fatty acid moiety released from the glycolipid after alkaline hydrolysis was studied by mass spectral analysis of the O-methylated and O-acetylated methyl ester derivatives. By argentation thin-layer chromatography, three species of O-acetylated methyl esters were recognized, corresponding to saturated, mono-unsaturated and di-unsaturated α-branched-β-hydroxylated fatty acids. The double bond was located by ozonolysis of the O-acetylated methyl ester derivatives, by gas chromatography of the reaction product and mass spectrometry of the effluent from the gas chromatograph. The main components of each species of α-branched-β-hydroxylated fatty acids found in the gly colipid fraction of C. diphtheriae were 2-tetradecyl-3-hydroxyoctadecanoic acid (C32H64O3, corynomycolic acid), 2-tetradecyl-3-hydroxy-11-octadecenoic acid (C32H62O3, corynomycolenic acid), 2-tetradec-7′-enyl-3-hydroxy octadecanoic acid (C32H62O3) and 2-tetradec-7′-enyl-3-hydroxy-11-octadecenoic acid (C32H60O3, corynomycoldienic acid). The glycolipid fraction from C. diphtheriae is obviously a complex mixture of 6,6′-diesters of trehalose. 相似文献
1000.
The effects of estrogen on the uridine uptake into cells were examined in primary cultures of liver parenchymal cells from Xenopus laevis. The total uptake of [3H]uridine into the estrogen-treated cells and its incorporation into RNA were about 1.5 times higher than the values for control cells. The uptake of [3H]adenosine and its incorporation into RNA were not affected by estrogen. An experiment in which liver parenchymal cells were double labeled with [3H]uridine and [3H]adenosine showed that estrogen elevated the specific radioactivity of the UTP pool 1.4-fold the value found for the control cells, but that of the ATP pool was not altered by estrogen. Short term labeling revealed that estrogen did not significantly alter the rate of the initial uptake of [3H]uridine into the cells, but it did stimulate [3H]uridine phosphorylation about 1.7-fold. Uridine kinase activity measured in cell-free extracts of hepatocytes treated with estrogen had a value 1.6 times that of the control cells. These data indicate that the stimulation of [3H]uridine uptake and phosphorylation in Xenopus laevis hepatocytes in the presence of estrogen is caused by the enhancement of uridine kinase activity. 相似文献