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51.
Lymphatic drainage in patients after replantation of extremities   总被引:1,自引:0,他引:1  
Lymph drainage was studied by means of lymph scintigraphy in eight patients in whom successful replantation of a totally or subtotally amputated extremity had been performed. Scintigrams were made after subcutaneous injection of technetium-99m in the replanted part of the patient and the contralateral, normal extremity. In all scintigrams, axillary or inguinal lymph node activity is seen, implying drainage of lymph by means of the lymph vessels. Retention of colloid in the replanted part (79 to 94 percent) shows no significant difference with the contralateral, normal side (86 to 94 percent). Unquestionable evidence of regeneration of lymphatics in humans is delivered in the three patients, in whom lymph node activity and normal retention percentages are seen on the scintigrams after total amputation of an extremity followed by replantation without anastomosing of interrupted lymph vessels.  相似文献   
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A bacterial cDNA clone was identified carrying one third of the nucleotides coding for elongation factor EF-1 alpha from the brine shrimp Artemia. The sequence of codons corresponds with the known sequence of amino acids of EF-1 alpha in the region involved.  相似文献   
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The possibility to utilize fiber sludge, waste fibers from pulp mills and lignocellulose-based biorefineries, for combined production of liquid biofuel and biocatalysts was investigated. Without pretreatment, fiber sludge was hydrolyzed enzymatically to monosaccharides, mainly glucose and xylose. In the first of two sequential fermentation steps, the fiber sludge hydrolysate was fermented to cellulosic ethanol with the yeast Saccharomyces cerevisiae. Although the final ethanol yields were similar, the ethanol productivity after 9.5?h was 3.3?g/l/h for the fiber sludge hydrolysate compared with only 2.2?g/l/h for a reference fermentation with similar sugar content. In the second fermentation step, the spent fiber sludge hydrolysate (the stillage obtained after distillation) was used as growth medium for recombinant Aspergillus niger expressing the xylanase-encoding Trichoderma reesei (Hypocrea jecorina) xyn2 gene. The xylanase activity obtained with the spent fiber sludge hydrolysate (8,500?nkat/ml) was higher than that obtained in a standard medium with similar monosaccharide content (1,400?nkat/ml). Analyses based on deglycosylation with N-glycosidase?F suggest that the main part of the recombinant xylanase was unglycosylated and had molecular mass of 20.7?kDa, while a minor part had N-linked glycosylation and molecular mass of 23.6?kDa. Chemical analyses of the growth medium showed that important carbon sources in the spent fiber sludge hydrolysate included xylose, small aliphatic acids, and oligosaccharides. The results show the potential of converting waste fiber sludge to liquid biofuel and enzymes as coproducts in lignocellulose-based biorefineries.  相似文献   
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Bonobos have a reputation as a female-dominated and egalitarian species. We examined the 2 aspects of dominance in 6 captive bonobo groups. Females do not consistently evoke submission from all males in all contexts. Though females occupy the highest-ranking positions in the dominance hierarchy, there are in each group males that obtain rather high ranks and are able to dominate ≥1 female. Thus female dominance is not complete and hierarchies can be better described as nonexclusive female dominance. We studied egalitarianism by measuring linearity and steepness of dominance hierarchies. The hierarchies of all groups are highly linear. Hierarchies among males are steeper than among females. On average, male bonobos are more despotic than females, but females too can have despotic relations, both with other females and with males. Hence one can call bonobos in captivity semidespotic rather than egalitarian.  相似文献   
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Epithelial cell islets in primary monolayer cultures of human breast biopsies were characterized by combined immuno-, enzyme- and DNA cytochemistry as well as by analysis of attachment-, spread- and growth patterns. For cultivation we used explants from reduction mammoplasties, benign lesions, primary carcinomas and metastases. Milk fat globule membrane antigen (MFGM-A) was detected with a monoclonal antibody, and the tetrazolium reaction for glucose 6-phosphate dehydrogenase (G6PDH) as well as DNA content of the cultured cells were quantified. Spreading and growth of individual islets were studied by image analysis. Fibroblast-like cells did not express MFGM-A, and whereas epithelial (MFGM-A positive) cell islets of normal and benign origin showed cells with no or low G6PDH reaction, respectively, the majority of epithelial cell islets from 11 out of 21 carcinomas showed strong reaction. Cell islets with strong G6PDH reaction were sometimes hyperdiploid. Moreover, whereas cell islets with no or low reaction from both benign lesions and carcinomas readily attached and spread in a serum-free medium and showed population doubling times of 30 to 110 h, cell islets with strong reaction from carcinomas and metastatic lesions required serum for attachment and their growth rate was too low to be determined.  相似文献   
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The effects of the thyroid status on the Ca++-transporting capabilities of rat slow skeletal muscle (m.soleus) were studied. The oxalate supported Ca++-uptake activity and Ca++-loading capacity of muscle homogenates from hyperthyroid rats showed an approximate 4.2 and 2.5 fold increase, respectively, as compared to values found in the hypothyroid group. Muscle homogenates of euthyroid rats gave intermediate values. The specific activity of oxalate supported Ca++ uptake, but not the Ca++-loading capacity, of membrane preparations enriched with respect to sarcoplasmic reticulum (SR) increased in proportion to the thyroid status. This was paralleled by a 3.5 fold increase in the amount of active Ca++ pumps in the SR preparations in the transition from hypothyroidism to hyperthyroidism as determined by measurement of Ca++-dependent 32P incorporation. These observations are not explained by differences in degree of purification of the examined SR preparations. Protein profiles of the membrane preparations obtained by gel electrophoresis indicated a thyroid-hormone dependent increase in Ca++-pump content relative to other SR proteins. The results suggest that thyroid hormone stimulates the proliferation of the SR and possibly also increases the Ca++-pump density in the SR membrane.  相似文献   
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