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1.
One hundred and forty five women who had undergone hemiarthroplasty for a subcapital fracture of the femoral neck but who were otherwise fit were studied to determine whether undue delay between injury and operation influenced their social circumstances three months after surgery. The median delay for those patients who showed good rehabilitation at three months was 29 hours, but for those who showed poor rehabilitation it was 57 hours. This difference was significant. It is suggested that a subcapital fracture in an otherwise fit elderly patient should therefore be regarded as a surgical emergency. 相似文献
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A comparison of uterine contraction induced by PGE1 and oxytocin in Ca-free solution 总被引:1,自引:0,他引:1
The contraction of the rat uterus incubated in Ca-free EDTA-containing solution in response to PGE1, oxytocin and vanadate has been investigated in order to examine the mechanism of the release of Ca from intracellular stores. The results obtained show that PGE1 evoked a sustained contraction the magnitude of which diminishes slightly after successive additions of PGE1 but not after long exposure to Ca-free medium. Oxytocin induced two different contractions: one of them was transient and observed only after incubating for 5 min in Ca-free solution; the other remained constant during prolonged incubation in Ca-free medium. Vanadate, an inhibitor of Ca-ATPase, induced sustained contraction after prolonged exposure to Ca-free medium, and isoprenaline, which stimulates Ca re-uptake by intracellular organelles, counteracted the sustained contractile response induced by the three agonists. 相似文献
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P de Paz Cabello M Fernandez C A Chamorro J G Fernandez J M Villar 《Acta anatomica》1988,132(1):12-16
The neuroectodermal cells of chick embryos have been analyzed during neurulation by stereological and morphometrical ultrastructural methods in an attempt to describe their cytometric evolution. A profound change of cellular form coefficient was observed which is related to the typical process of columnarization of these cells. At stages 7 and 8, the nucleus appeared round in shape, probably due to a loss of pressure of the vitelline inclusions. In this sense, the volume density of these inclusions falls during this period. There was also a significant increase of the nuclear surface density, the significance of which is discussed on the basis of the nucleo-cytoplasmic interchanges and the differentiation process. At the same time, an increase in the number of mitochondria was observed, which is related to the neural folding process. Simultaneously, the amount of rough endoplasmic reticulum increases, presumably related to the remarkable changes of the embryonic extracellular matrix. 相似文献
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Isolation and characterization of Pediococcus halophilus from salted anchovies (Engraulis anchoita) 总被引:3,自引:0,他引:3
M Villar A P de Ruiz Holgado J J Sanchez R E Trucco G Oliver 《Applied and environmental microbiology》1985,49(3):664-666
The presence of bacteria in salted anchovies during and at the end of the curing process was investigated. Attempts to isolate bacteria under aerobic or anaerobic conditions led to the isolation of only bacteria of the genus Pediococcus which were identified as Pediococcus halophilus. The isolates correspond to a rather heterogeneous group in which some of the members differ in some biochemical tests from the types described in the literature. 相似文献
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The ultrastructure of endoderm cells of the area pellucida has been analysed in the chick embryo by stereological methods. These cells show a specific subcellular evolution which can be correlated with several aspects of morphogenetic behaviour. The cell form coefficient (CFc) changes notably from stage 5 (0.683) to stage 8 (0.446) accompanying the transformation of this layer into a squamous epithelium. An increase of the nuclear surface density is observed and is discussed in relation to the control of nucleocytoplasmic interchange. The mitochondrial volume and surface densities remain constant (3.12% of cellular volume and 0.727 mitochondria/mu(3) respectively). The endodermal cells possess higher levels of vitelline reserves (lipid bodies, 6.97% and yolk droplets, 8.90%) than other cellular types of the chick embryo. This fact is discussed with respect to the role of the endoderm in the phagocytosis of yolk. The RER length density shows an increase that could be related to some specific changes of the extracellular matrix during this period, but this fact remains to be demonstrated in relation to changes of Golgi membranes. 相似文献
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Summary In order to understand the nature of interspecific barriers in Populus, we have explored pollen/pistil interactions in intra- and interspecific crosses Populus nigra x P. nigra and P. nigra x P. alba. The kinetics of pollen-tube growth demonstrated that P. nigra and P. alba pollen tubes have distinct behavioral patterns inside P. nigra pistils. P. alba pollen tubes exhibit an unique S-shaped growth curve and an arrested growth site near the sylodium. P. nigra pollen tubes exhibit two growth phases, in the stigmatic tissues and in the ovarian cavity respectively. P. nigra and P. alba curves diverge 5 h after controlled pollination and could be related to a change in the physiology of the P. nigra pollen tube, which shifts from an autotrophic to a heterotrophic type of nutrition. Protein analysis of pollinated stigmatic extracts (0,6 and 20 h after pollination) revealed qualitative and quantitative differences that are related to the presence of either P. nigra or P. alba pollen tubes inside the stigmatic tissues. Increasing numbers of protein bands were detectable from 0 to 20 h after pollination only in intraspecific cross. Glycoproteins were detected, and the differences observed were dependent of the cross. -Galactosidase activity was found in pollinated stigmas, but an increase in its activity (one isozyme of pHi 4.2) between 6 h and 20 h after pollination was detected only in the intraspecific cross. This enzyme could play a role in heterotrophic pollen-tube nitrition, and its activity could be the final result of a series of interactions started by the initial pollen-stigma dialog. 相似文献
10.
Structural requirements in the reaction of morphine uridine diphosphate glucuronyltransferase with opioid substances. 下载免费PDF全文
The influence of the 3-hydroxyl and N-alkyl groups in the reactivity of narcotic compounds with morphine UDP-glucuronyltransferase was studied. Opioids possessing both, one or none of these groups were tested for inhibition of morphine glucuronidation in rabbit liver microsomal preparations. Compounds with only a 3-hydroxyl group (normorphine) or an N-methyl group (codeine, ethylmorphine) were less potent competitive inhibitors than those containing both groups (dextrorphan). Norcodeine, with neither of these groups, had no inhibitory effect. The synthetic narcotics (+)- and (-)-methadone, (-)-alpha-acetylmethadol and meperidine, with only an N-alkyl group, were effective competitive inhibitors. No stereoselectivity of the morphine glucuronyltransferase for opioid isomers was observed, and [methionine]enkephalin does not react with morphine glucuronyltransferase. Differences of pKa values and water/lipid solubility of narcotics could not explain the effects. Results indicate that the N-alkyl group plays a critical role in the interaction of narcotics with the morphine UDP-glucuronyltransferase. 相似文献