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971.
Mousumi Bose Sriram Machineni Blanca Oliván Julio Teixeira James J. McGinty Baani Bawa Ninan Koshy Antonia Colarusso Blandine Laferrère 《Obesity (Silver Spring, Md.)》2010,18(6):1085-1091
The goal of this study was to understand the mechanisms of greater weight loss by gastric bypass (GBP) compared to gastric banding (GB) surgery. Obese weight‐ and age‐matched subjects were studied before (T0), after a 12 kg weight loss (T1) by GBP (n = 11) or GB (n = 9), and at 1 year after surgery (T2). peptide YY3–36 (PYY3–36), ghrelin, glucagon‐like peptide‐1 (GLP‐1), leptin, and amylin were measured after an oral glucose challenge. At T1, glucose‐stimulated GLP‐1 and PYY levels increased significantly after GBP but not GB. Ghrelin levels did not change significantly after either surgery. In spite of equivalent weight loss, leptin and amylin decreased after GBP, but not after GB. At T2, weight loss was greater after GBP than GB (P = 0.003). GLP‐1, PYY, and amylin levels did not significantly change from T1 to T2; leptin levels continued to decrease after GBP, but not after GB at T2. Surprisingly, ghrelin area under the curve (AUC) increased 1 year after GBP (P = 0.03). These data show that, at equivalent weight loss, favorable GLP‐1 and PYY changes occur after GBP, but not GB, and could explain the difference in weight loss at 1 year. Mechanisms other than weight loss may explain changes of leptin and amylin after GBP. 相似文献
972.
A new mixed-valence copper coordination polymer with copper-copper metal bonds in a two-dimensional network was generated from an in situ oxidation reaction route under hydrothermal conditions. The synthesis of this coordination polymer demonstrated that the novel compounds that may not be accessible using the known methods could be synthesized via an oxidation reaction route. The reaction conditions are mild enough to keep the building blocks intact during the oxidation and self-assembly process under hydrothermal conditions. 相似文献
973.
Human placental α-l-fucosidase has been purified 670-fold with a 57% yield by a one-step affinity chromatographic procedure using agaroseepsilon-amino-caproyl-fucosamine. 相似文献
974.
The construction of a Perspex slide holder for use in immune staining is described. The apparatus allows large numbers of slides to be stained at once and makes the procedure less tedious than it would otherwise be. 相似文献
975.
976.
Olatz Arteaga Miren Revuelta Leyre Urigüen Antonia álvarez Haizea Montalvo Enrique Hilario 《PloS one》2015,10(11)
Despite advances in neonatal care, hypoxic-ischemic brain injury is still a serious clinical problem, which is responsible for many cases of perinatal mortality, cerebral palsy, motor impairment and cognitive deficits. Resveratrol, a natural polyphenol with important anti-oxidant and anti-inflammatory properties, is present in grapevines, peanuts and pomegranates. The aim of the present work was to evaluate the possible neuroprotective effect of resveratrol when administered before or immediately after a hypoxic-ischemic brain event in neonatal rats by analyzing brain damage, the mitochondrial status and long-term cognitive impairment. Our results indicate that pretreatment with resveratrol protects against brain damage, reducing infarct volume, preserving myelination and minimizing the astroglial reactive response. Moreover its neuroprotective effect was found to be long lasting, as behavioral outcomes were significantly improved at adulthood. We speculate that one of the mechanisms for this neuroprotection may be related to the maintenance of the mitochondrial inner membrane integrity and potential, and to the reduction of reactive oxygen species. Curiously, none of these protective features was observed when resveratrol was administered immediately after hypoxia-ischemia. 相似文献
977.
Gibberellic acid (GA) has no effect on abscission when applied proximally or distally to the abscission zones of debladed petioles of Coleus. Application of GA to the stem apex increases the rate of abscission of debladed petioles. The effect on abscission is accompanied by an increase in the level of endogenous auxin in the stem. Correspondingly proximal applications of indoleacetic acid (IAA) accelerate abscission, whereas the longevity of the debladed petiole approaches that of the intact leaf only in the presence of a continuous distal supply of IAA. No correlation is found between petiole elongation and its longevity. The experimental data support the view that auxin acts at the abscission zone in regulating separation processes and that the effect of GA is through its effect on the level of endogenous auxin. 相似文献
978.
979.
Jack Rosenbluth 《The Journal of cell biology》1971,50(3):900-904
980.
In order to show whether the estrogen complex (ER) in the intact cell binds to some nuclear component or whether it is in free equilibrium between the cytoplasm and the nucleus, we incubated intact uteri under conditions which increased the ratio of nuclear to cytoplasmic ER. These conditions included (a) the use of sucrose at concentrations greater than 0.75 M, (b) ethanol at 7.5% to 10%, or (c) 1 mM mercuric chloride or phenylmercuric acetate. Whereas (b) and (c) increased the ratio by preferentially denaturing the cytoplasmic ER, (a) caused ER to move from the cytoplasm into the nucleus by an undetermined mechanism. Uteri with a high ratio of nuclear to cytoplasmic ER were then washed, incubated in fresh “normal” incubation media, fractionated and the location of ER determined. If ER binding does occur in the nucleus, the high ratio of nuclear ER to cytoplasmic ER should be maintained, whereas if ER is in an equilibrium in the cell, ER should redistribute and reestablish the “normal” ratio. In all cases studied; i.e., after pretreatment with sucrose at different concentrations, ethanol at different concentrations and either mercuric chloride or phenylmercuric acetate, the ratio of nuclear to cytoplasmic ER remained high, suggesting that ER binds to some nuclear component in intact cells. 相似文献