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991.
992.
We investigated repair of acrylamide (AA) induced damage in intestines by administration of crocin. We used 40 male Wistar rats in four groups of 10 animals: control, AA, crocin, and AA + crocin groups. We investigated biochemical and histological changes to small and large intestine. AA ingestion decreased glutathione (GSH) levels and total antioxidant status (TAS) in the intestine compared to the control group, while superoxide dismutase (SOD) and catalase (CAT) activities, and total oxidant status (TOS) and malondialdehyde (MDA) levels were increased. Villi were shortened and villus degeneration was observed in ileum of the AA group. Degeneration of surface epithelium and Liberkühn crypts were observed in colon sections. GSH and TAS levels increased after administration of AA together with crocin, while SOD and CAT levels and TOS and MDA levels decreased; significant recovery of histological damage also was observed. We found that crocin exhibits protective effects on AA induced small and large intestine damage by inhibiting oxidative stress.  相似文献   
993.
Both 5% cholesterol feeding and fasting produced a decrease in the hepatic 3-hydroxy-3-methylglutaryl-CoA reductase activity, although certain diurnal variations remained during the second day of treatment. Supplementation of 5% cholesterol to the diet produced a significant increase in cholesterol content of hepatic microsomes, whereas no significant variations were observed after fasting. The phospholipid content of hepatic microsomes did not change by fasting. However, cholesterol feeding produced a clear decrease in microsomal phospholipids. After 7 hr of cholesterol feeding, an increase of nearly 3-fold in the cholesterol/lipidic phosphorus molar ratio was found. Fasting had no effect on this molar ratio. The changes observed by cholesterol feeding agree with a mechanism of regulation of hepatic reductase by alteration in membrane fluidity, a mechanism that would be already operative during the neonatal period.  相似文献   
994.
The rich vascular network of the gluteal and posterior thigh region provides for a larger range of flaps for reconstructive surgery than previously described. Facility with these flaps requires an appreciation of relevant anatomy, embryology, and anthropology. Structural changes in the gluteus maximus muscle are critical to the evolutionary advance toward an upright stance during walking. The superficial and deep segmentation of the gluteus maximus are best appreciated by phylogenic and ontogenetic study. Femoral arterial and gluteal arterial anastomotic hemodynamics are affected by the relative involution of the gluteal system in late embryogenesis. The gluteal thigh flap should include contributions from the femoral system when the cutaneous branch of the inferior gluteal artery cannot be identified. Huge sacral wounds can be closed with gluteus maximus myocutaneous flaps with maintenance of muscular function by detaching the entire origin, sliding the muscle medially, and reconstructing these attachments. By dissection between the divergent inserting fibers of the gluteus maximus, a long, superficial portion of the muscle can be raised that forms the basis of the extended gluteus maximus flap. The pedicle of the flap is at the level of the piriformis muscle and the skin paddle can be placed over the midportion of the posterior thigh. Finally, the first deep femoral perforating artery forms the basis of a posterolateral fasciae latae flap that is well suited for coverage of defects over the trochanter.  相似文献   
995.
From the roots of Tephrosia woodii, a new Mexican Tephrosia species, a new prenylated flavanone, oaxacacin, and its chalcone, mixtecacin, have been isolated and their structures elucidated from their chemical properties and spectral data.  相似文献   
996.
Phospholipid synthesis activity and plasma membrane growth have been studied in the Saccharomyces cerevisiae temperature-sensitive, secretion-defective mutants isolated by Novick and Schekman (Proc. Natl. Acad. Sci. U.S.A. 76:1858-1862, 1979; Novick et al., Cell 21:205-215, 1980). The mutants, sec1 through sec23, do not grow at 37 degrees C and exhibit lower rates of phospholipid synthesis than does the wild-type strain X2180. None of the mutants exhibits a decline in lipid synthesis rapid enough to explain secretion failure. Plasma membrane growth was assessed indirectly by examining the osmotic sensitivity of spheroplasts derived from cultures transferred from 24 to 37 degrees C. Spheroplasts from the normal-growing strain X2180 exhibited a small rapid increase in osmotic sensitivity and stabilized at a more sensitive state. Spheroplasts from the sec mutants exposed to the same temperature shift exhibited progressively increasing osmotic sensitivity. Cycloheximide treatment prevented progressive increases in osmotic fragility. These data are compatible with the hypothesis that plasma membrane expansion is restricted in the sec mutants. During incubation at 37 degrees C, the accumulation of intracellular materials within the no-longer expanding plasma membrane exerts osmotic stress on the membrane, increasing with time. The gene products defective in Novick and Schekman's sec mutants appear to be required for both extracellular protein secretion and plasma membrane growth in yeast cells.  相似文献   
997.
A new species of Blastobotrys Klopotek (1, 2, 4, 5) has been recovered from white pepper. It appears to be sufficiently distinct from B. nivea v. Klopotek. (5), B. proliferas Marvanová, and B. aristata Marvanová (2), to be described as a new species under the name of Blastobotrys navarrensis. Both morphological as well as physiological characteristics were taken in account to differentiate the new species from Blastobotrys species known up to date.  相似文献   
998.
999.
A Rhodospirillum rubum strain, F24.1, was isolated as a spontaneous phototrophic revertant from a nonphototrophic mutant with a defective reaction center. The revertant grew anaerobically in the light at a rate close to that of the wild-type strain and exhibited a normal light-induced increase of the internal ATP levels. However, continuous illumination of light-grown F24.1 cells failed to elicit any infrared absorbance changes which could be ascribed to changes in the redox state of reaction-center bacteriochlorophyll. The spectral properties of whole cells and of isolated chromatophores indicate that the reaction center of F24.1 is profoundly altered: It lacks the characteristic absorption band near 800 nm and shows an infrared shift of the absorption band which is reversibly bleached by potassium ferricyanide in the dark.  相似文献   
1000.
A cDNA for the pro alpha 2 chain of human type I collagen has been recently cloned and amplified. We have used this specific probe to identify the human chromosome carrying the pro alpha 2(I) collagen gene. The DNA from 17 independent human/hamster and human/mouse somatic cell hybrids was digested by Eco RI and the restriction pattern analyzed in Southern blot experiments, using the 32P-labeled cDNA as a hybridization probe. The gene coding for the pro alpha 2 collagen subunit could be unambiguously assigned to human chromosome 7. All the other chromosomes, including chromosome 17, were excluded.  相似文献   
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