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61.
In most cases, the loss of a free-tissue transfer is a disaster for both the patient and the surgeon. Seven patients received a second microvascular free-tissue transfer after loss of the first. The indications for free-tissue transfer included chronic osteomyelitis of the lower leg (four patients), acute traumatic defect of the leg (one patient), acute traumatic defect of the arm (one patient), and esophageal defect after surgical excision (one patient). In three patients, the interval between the first and second procedures was less than 2 weeks. The remaining four patients had their second free-tissue transfer performed 5 weeks to 21 months after the first. Six of the seven free flaps were successful. Two patients with venous obstruction occurring after the second free-tissue transfer were salvaged by reexploration. Partial loss of the flap was noted in one of these patients. It is concluded from this select group of patients that failure of a free-tissue transfer does not contraindicate a second microtissue transfer does not contraindicate a second microvascular free-tissue transfer. 相似文献
62.
M G Bitzan E May 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1992,50(1-2):127-144
The paper represents a cross-sectional study from a sample of 1800 out of 3000 school-children from the Braunschweiger L?ngsschnitt. In this methodical approach we first eliminate approximately the influence of age and stature on the raw data from all body measurements with regression equations. The transformed data were attached to three "types" named 'below normal', 'normal', and 'above normal', in course of which 'normal' means all cases in the range of the standard deviation, whereas the two other "types" are corresponding to the adjacent ranges of values. Subsequently each transformation on the mean of age and stature a discriminant analysis has been performed grouping the cases by the "types" of the width of pelvis, resp. shoulders. There were found great influences of the stature on the chosen measures of width in our investigated class of age. They could be made clear alone by using allometrical methods. Only before correction of the body height the given grouping is supported by other variables, at which different sets of variables dominate the discriminant functions for boys and girls. Out of this new aspects and considerations result for the understanding of the physique and the physique typologies, which would be significant in our opinion for acceleration phenomenon as well as for the comparative examinations on populations. 相似文献
63.
Subculturing of a polychlorinated biphenyl-dechlorinating anaerobic enrichment on solid media. 总被引:4,自引:4,他引:0
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An anaerobic culture capable of dechlorinating polychlorinated biphenyls was subcultured under strict anaerobic conditions on solid media containing sterilized river sediment. The dechlorination activity was transferred as a bacterial colony on a solid medium three times. After two transfers on solid medium, the culture was no longer methanogenic but still dechlorinated a mixture of tri- and tetrachlorobiphenyls. This demonstrates that anaerobic bacteria are responsible for the polychlorinated biphenyl dechlorination and can be grown without polychlorinated biphenyl on solid media. 相似文献
64.
John R. Atack Conrad May Jeffrey A. Kaye Stanley I. Rapoport 《Neurochemistry international》1990,16(4):533-538
Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were measured in 13 sequential 2 ml aliquots of cerebrospinal fluid (CSF) obtained by lumbar puncture from 7 young and 7 elderly healthy normal subjects. The slopes of the rostrocaudal gradients of AChE and BChE were calculated and compared to those of total protein concentration and the major dopaminergic metabolite homovanillic acid (HVA), for which a pronounced rostrocaudal gradient (with highest concentrations of HVA in more rostral CSF) is consistent with HVA originating primarily from the brain. AChE activity was higher in more caudal fractions of young, but not elderly subjects and there was a significant difference between the mean AChE gradient slopes in the young and old groups. These results suggest that the spinal cord makes an important contribution to AChE activity in lumbar CSF. Furthermore, the absence of a negative AChE gradient in elderly subjects may be the result of a greater rate of entry of cerebral AChE into CSF, possibly as a consequence of an increased ventricular surface area and shorter diffusion distances in atrophic elderly brains. In contrast to AChE, BChE activity and total protein concentrations were higher in more caudal CSF fractions of not only young but also old subjects. In addition, there was a significant correlation between the gradient slopes of BChE activity and total protein concentrations, suggesting that the majority of BChE activity in lumbar CSF derives from the same source as the majority of total protein, namely plasma. The diffuse (i.e. brain and spinal cord) origin of AChE in lumbar CSF would explain the relatively modest changes in lumbar CSF AChE activity in diseases involving certain central cholinergic systems, most notably Alzheimer's disease. 相似文献
65.
Applications of fractals in ecology 总被引:2,自引:0,他引:2
Fractal models describe the geometry of a wide variety of natural objects such as coastlines, island chains, coral reefs, satellite ocean-color images and patches of vegetation. Cast in the form of modified diffusion models, they can mimic natural and artificial landscapes having different types of complexity of shape. This article provides a brief introduction to fractals and reports on how they can be used by ecologists to answer a variety of basic questions, about scale, measurement and hierarchy in, ecological systems. 相似文献
66.
Leonhard Schnittger Jürgen May Christina Kretschmer Peter G. Kremsner C. G. Meyer 《Immunogenetics》1996,44(5):405-406
The nucleotide sequence data reported in this paper have been submitted to the EMBL nucleotide sequence database and have
been assigned the accession number X96986. The nameDPB1
*
6601 was officially assigned by the WHO Nomenclature Committee in May 1996. This follows the agreed policy that, subject to the
conditions stated in the most recent Nomenclature Report (Bodmer et al. 1995), names will be assigned to new sequences as
they are identified. Lists of such sequences will be published in the following WHO Nomenclature Report 相似文献
67.
68.
69.
Christoph Theurer Hans-Joachim Treumann Thomas Faust Ursula May Wolfgang Kreis 《Plant Cell, Tissue and Organ Culture》1994,38(2-3):327-335
The glycosylation and deglycosylation of cardiac glycosides was investigated using cell suspension cultures and shoot cultures, both established from Digitalis lanata EHRH. plants, as well as isolated enzymes. Shoots were capable of glucosylating digitoxigenin, evatromonoside, digiproside, glucodigitoxigenin and digitoxin. Suspension cultured Digitalis cells glucosylated all the substrates mentioned but digiproside, whereas the UDP-glucosedependent cardinolide glucosyltransferase isolated from that source did not accept digitoxigenin and digiproside as substrates. It is concluded that at least three different glucosyltransferases are involved in cardiac glycoside formation in Digitalis. Similar experiments carried out with glucosylated cardenolides which were administered to cultured cells, shoots and a cardenolide -glucosidase isolated from young leaves revealed that at least two different glucosidases occur in Digitalis lanata, albeit in different tissues or during different phases of development. The biotransformation of glucoevatromonoside was investigated using unlabelled compound and [14C-glucose]-glucoevatromonoside synthesized enzymatically. After 7 d of incubation almost no radioactivity could be recovered from the cardenolide fraction, indicating that the terminal glucose of glucoevatromonoside was now incorporated into volatile, hydrophilic and insoluble compounds. Since, on the other hand, large amounts of cardenolides were found in the experiments with unlabelled glucoevatromonoside it is assumed that steady state or pool size regulation is achieved by the coordinated action of a cardenolide glucosidase and a glucosyltransferase.Abbreviations Acdox
D-acetyldigitoxose
- dgen
digoxigenin
- dox
D-digitoxose
- dten
digitoxigenin
- dtl
D-digitalose
- fuc
D-fucose
- gten
gitoxigenin
- qun
D-quinovose
- CGH
cardenolide 16-O-glucohydrolase
- DFT
UDP-fucose:digitoxigenin 3-O-fucosyltransferase
- DGT
UDP-glucose:Digitoxin 16-O-glucosyltransferase
- DQT
UDP-quinovose:digitoxigenin 3-O-quinovosyltransferase 相似文献
70.
Ursula Kües Anna M. Tymon Wendy V. J. Richardson Georgiana May Paul T. Gieser Lorna A. Casselton 《Molecular & general genetics : MGG》1994,245(1):45-52
We have identified the seven genes that constitute the A43 mating-type factor of Coprinus cinereus and compare the organisation of A43 with the previously characterised A42 factor. In both, the genes that trigger clamp cell development, the so-called specificity genes, are separated into and loci by 7 kb of noncoding sequence and are flanked by homologous genes -fg and -fg. The specificity genes are known to encode two classes of dissimilar homeodomain (HD1 and HD2) proteins and have different allelic forms which show little or no cross-hybridisation. By partial sequencing we identified a divergently transcribed HD1 (a1-2) and HD2 (a2-2) gene in the A43 locus. a2-2 failed to elicit clamp cell development in three different hosts, suggesting that it is non-functional. a1-2 elicited clamp cells in an A42 host that has only an HD2 gene (a2-1) in its locus, thus demonstrating that the compatible A mating interaction is between an HD1 and an HD2 protein. The A43 locus contains three specificity genes, the divergently transcribed HD1 and HD2 genes b1-2 and b2-2 and a third HD1 gene (d1-1) that was shown by hybridisation and transformation analyses to be functionally equivalent to d1-1 in A42. An untranscribed footprint of a third A42 HD1 gene, c1-1, was detected between the A43 b2-2 and d1-1 genes by Southern hybridisation. 相似文献