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91.
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
92.
M J D'Occhio D R Gifford C R Earl T Weatherly W von Rechenberg 《Journal of reproduction and fertility》1989,85(2):495-502
Post-partum acyclic beef cows received continuous long-term treatment with GnRH (200 or 400 ng/kg body wt/h) or the GnRH agonist buserelin (5.5 or 11 ng/kg body wt/h) using s.c. osmotic minipumps which were designed to remain active for 28 days. All treatments increased circulating LH concentrations whereas FSH remained unchanged. Ovulation and corpus luteum (CL) formation as judged by progesterone concentrations greater than or equal to 1 ng/ml occurred in 0/5 control, 4/5 200 ng GnRH, 4/4 400 ng GnRH, 4/5 5.5 ng buserelin and 3/5 11 ng buserelin cows. The outstanding features of the progesterone profiles were the synchrony, both within and across groups, in values greater than or equal to 1 ng/ml around Day 6, and the fact that most CL were short-lived (4-6 days). Only 3 cows, one each from the 400 ng GnRH, 5.5 ng buserelin and 11 ng buserelin groups, showed evidence of extended CL function. Cows failed to show a second ovulation which was anticipated around Day 10 and this could have been due to insufficient FSH to stimulate early follicular development, or the absence of an endogenously driven LH surge. The highest LH concentrations for the respective groups were observed on Days 2 and 6 and by Day 10 LH was declining, although concentrations did remain higher than in controls up to Day 20.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
93.
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
94.
Subculturing of a polychlorinated biphenyl-dechlorinating anaerobic enrichment on solid media. 总被引:4,自引:4,他引:0 下载免费PDF全文
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
95.
James M. Caffrey Harry A. Smith John C. Schmitz Andrea Merchant Earl Frieden 《Biological trace element research》1990,25(1):11-19
The hemolysis of red blood cells (RBC) induced by Cu(II) is modified by ceruloplasmin (Cp) and albumin. The time course of hemolysis for rabbit RBC by Cu(II) consisted of two parts, an induction period followed by a catastrophic lysis period. The induction period decreased and the lysis rate increased with increasing Cu(II) concentration. Cp or albumin, modified Cu(II) induced hemolysis, by increasing the duration of the induction period and decreasing the overall rate of hemolysis of RBC. The catastrophic lysis period coincided with a sharp increase in the formation of metHb within the cell and in a rapid uptake of Cu(II). The presence of Cp led to an increase in the induction period prior to the rapid increase in metHb formation and in Cu(II) uptake. Porcine Cp was prepared with either two or three nonprosthetic copper binding sites (sites where Cu(II) is easily removed by passing over Chelex-100). Cp with three nonprosthetic binding sites gave more protection than Cp with two. Likewise, albumin can be prepared with three and five nonprosthetic copper binding sites. The albumin with five sites gave more protection than the albumin with three sites. 相似文献
96.
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
97.
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
98.
Folding, assembly, and intracellular trafficking of the human immunodeficiency virus type 1 envelope glycoprotein analyzed with monoclonal antibodies recognizing maturational intermediates. 总被引:8,自引:5,他引:3 下载免费PDF全文
Monoclonal antibodies (MAbs) that bind linear or conformational epitopes on monomeric or oligomeric human immunodeficiency virus type 1 (HIV-1) envelope glycoproteins were screened for their recognition of maturational intermediates. On the basis of reactivities with gp160 at different times after pulse-labeling, the MAbs were sorted into groups that exhibited binding which was immediate and constant, immediate but transient, delayed, late, or very late. This grouping was consistent with the selectivity of the MAbs for structural features of gp160. Thus, a MAb to the V3 loop reacted with envelope proteins at all times, in accord with the relative conformational independence and accessibility of the epitope. Several MAbs that preferentially react with monomeric gp160 exhibited diminished binding after the pulse. A 10-min tag occurred before gp160 reacted with conformational MAbs that inhibited CD4 binding. The availability of epitopes for other conformational MAbs, including some that react equally with monomeric and oligomeric gp160 and some that react better with oligomeric forms, was half-maximal in 30 min and closely followed the kinetics of gp160 oligomerization. Remarkably, there was a 1- to 2-h delay before gp160 reacted with stringent oligomer-specific MAbs. After 4 h, approximately 20% of the gp160 was recognized by these MAbs. Epitopes recognized by monomerspecific or CD4-blocking MAbs but not by oligomer-dependent MAbs were present on gp160 molecules associated with the molecular chaperone BiP/GRP78. MAbs with a preference for monomers reacted with recombinant or HIV-1 envelope proteins in the endoplasmic reticulum, whereas the oligomer-specific MAbs recognized them in the Golgi complex. Additional information regarding gp160 maturation and intracellular trafficking was obtained by using brefeldin A, dithiothreitol, and a low temperature. 相似文献
99.
Earl F. Albone Fred K. Hagen Claude Szpirer Lawrence A. Tabak 《Glycoconjugate journal》1996,13(5):709-716
Mucin glycoproteins are a major constituent of salivary secretions and play a primary role in the protection of the oral cavity. Rat submandibular glands (RSMG) synthesize and secrete a low molecular weight (114 kDa) mucin glycoprotein. We have isolated, partially sequenced, and characterized the gene which encodes the RSMG apomucin. The gene is encoded by three exons of 106 nt, 69 nt, and 991 nt, separated by introns of 921 nt and 12.5 kb. CAAT and TATA elements are present, at –68 and –26, respectively, in the 5 flanking sequence of the RSMG apomucin gene. The tandem repeat domain present in exon III consists of ten tandem repeats of 39 nt encoding the consensus sequence PTTDSTTPAPTTK. Sequence comparison and organization of the nucleic acid sequence encoding the tandem repeats of two alleles for this gene suggests that the apomucin gene has undergone recombinational events during its evolution. No significant sequence similarity was found with other mucin genes, or with other known salivary gland-specific genes. The gene was localized to rat chromosome 14 using somatic cell hybrids that segregate rat chromosomes. Since this, to our knowledge, represents the first RSMG mucin gene cloned, we have designated this geneMucsmg.Abbreviations RSMG
rat submandibular gland
- RSM
rat salivary mucin
- GRP
glutamine-glutamic-acid rich protein
- nt
nucleotide
- kb
kilobase
Sequences reported herein have been assigned GenBank accession numbers U33441 and U33442. 相似文献
100.
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