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91.
Endoscopic eyebrow lift was performed on 51 patients presenting with eyebrow ptosis due to facial paralysis. The resulting anthropometric measurements of eyebrow position were analyzed statistically to evaluate the effectiveness of this method. When preoperative eyebrow differences between the paralyzed and nonparalyzed sides were measured, the average difference at midpoint was 4.4 mm, and at the highest point, 4.6 mm. When the same points were measured postoperatively, the average difference at midpoint was 2.4 mm, and at the highest point, 2.3 mm. The difference in eyebrow height between the paralyzed and nonparalyzed sides correlated positively with age, both preoperatively and postoperatively. However, differences between preoperative and postoperative eyebrow height (which reflects the effectiveness of endoscopic eyebrow lift) at the highest point did not correlate with age and at the midpoint displayed a slightly negative correlation with age. These results suggest that endoscopic eyebrow lift is effective among young patients whose eyebrow ptosis is minor and is relatively ineffective among elderly patients whose eyebrow ptosis is severe. The conventional method of juxta-brow excision is indicated for elderly patients, for whom the operative scar is almost inconspicuous.  相似文献   
92.
Interspecific mutualisms are ubiquitous in nature, despite their ecological and evolutionary instability. Recent studies have developed coevolutionary theory of mutualisms, which coupled population and evolutionary dynamics, to resolve the longstanding puzzle. However, earlier studies assumed a time-scale separation between these dynamics, leaving an unanswered question of how a relaxation in the time-scale separation affects the coevolutionary dynamics of mutualism. Here I relax the strong assumption to theoretically show that ecological and evolutionary dynamics occurring in a similar time scale can stabilize an otherwise unstable mutualism. I show that the coevolutionary dynamics can cause a stable limit cycle or stable equilibrium in the population sizes, even if the population sizes increase unbounded in the absence of evolutionary adaptation. In contrast, coevolution can also cause stable limit cycle even if the population dynamics is stable in the absence of evolutionary adaptation. Furthermore, the model predicts that the population dynamics is likely to converge to equilibrium when the evolutionary speed of two species is similar and fast or highly dissimilar. The results suggest that the ease of the evolutionary ‘arms race’ is of crucial importance to maintain mutualism.  相似文献   
93.
Flow cytometry enables comparative quantification, population analysis, and high-throughput screening of agonist-mediated G-protein-coupled receptor (GPCR) signaling in genetically engineered yeasts. By using flow cytometry, we found that transformation of yeast cells with a low plasmid number is critical both for the construction of large screening libraries and for stable signal transmission in cell ensembles. Based on these findings, we constructed an engineered yeast strain for the improved identification of signal promotion by Gα(i)-specific human GPCRs using flow cytometry.  相似文献   
94.
We previously showed that skin-homing CD4 T cells in peripheral blood can be subdivided into three populations on the basis of the expression pattern of the cutaneous lymphocyte Ag (CLA) and fucosyltransferase VII (FucT-VII): FucT-VII(+)CLA(-), FucT-VII(+)CLA(+), and FucT-VII(-)CLA(+). In view of the known late appearance of CLA during T cell differentiation, T cells programmed to attain skin-homing properties may start to generate E-selectin-binding epitopes at early stages of differentiation before induction of CLA expression. To this end, the in vitro differentiation from naive to CLA(+) memory T cells was followed after activation with anti-CD3 mAb. Here we demonstrate that naive skin-homing CD4 T cell precursors undergo a linear differentiation process from the FucT-VII(+)CLA(-) phenotype to the FucT-VII(+)CLA(+) phenotype and eventually to the FucT-VII(-)CLA(+) phenotype. The appearance of the FucT-VII(+)CLA(-) subset coincided with or could be immediately followed by the generation of E-selectin binding epitopes, and even after E-selectin-binding epitopes were no longer detectable, CLA remained expressed for prolonged periods of time, suggesting that induction of functional E-selectin ligands depends primarily on the expression of FucT-VII, but not CLA. Immunofluorescence and confocal microscopy studies of these T cells confirm that most E-selectin ligands were found independently of CLA expression.  相似文献   
95.
The elongation of arachidoyl-CoA by swine cerebral microsomes resulted in the production of behenic acid (22:0) and lignoceric acid (24:0) concomitantly. When 4S-[4-2H1]NADPH was used for the elongation of arachidoyl-CoA, the incorporation of two deuterium atoms into 22:0 was observed by the technique of mass fragmentography. Furthermore, the incorporation of four deuterium atoms into 24:0 was also detected. On the other hand, when 4R-[4-2H1]NADPH was used, no deuterium was incorporated into the elongated products.  相似文献   
96.
Proposal of leukotoxin, 9,10-epoxy-12-octadecenoate, as a burn toxin   总被引:3,自引:0,他引:3  
It is postulated that toxic substances (burn toxin) synthesized in burned skin are transferred into general circulation and cause multiple organ failure. We found a highly cytotoxic substance, leukotoxin, a linoleate epoxide, exists in burned skin. Leukotoxin, as the name indicates, was synthesized by leukocytes from linoleate as a substrate. The aim of this study is to evaluate the possibility of leukotoxin as a burn toxin. We studied plasma leukotoxin level of four patients with extensive burns (over 50% of body surface area) and examined coagulation studies in these patients. We detected considerable amounts of leukotoxin (11.4 nmol/ml-37.0 nmol/ml) in all patients. Leukotoxin was not detected in the control subjects. Pulmonary edema, cardiac failure, and coagulation abnormalities were found in these patients. Exogeneously administered leukotoxin induced similar pathological conditions in experimental animals to those observed in patients with extensive burns. Hence, it is concluded that leukotoxin is a responsible substance as a burn toxin.  相似文献   
97.
Regular collections of ichthyoplankton were made with a larva net at 9–14 stations from Oct. 1983 to Dec. 1988 in Kagoshima Bay, totalling 817 collections from 66 cruises. A total of 2172 bregmacerotid larvae obtained from 195 collections of 33 cruises were identified asB. atlanticus (2001),B. neonectabanus (169),B. macclellandii (1) andB. nectabanus (1, tentative identification). The peaks of mean densities of larvae collected occurred in autumn forB. atlanticus andB. neonectabanus. The larvae ofB. atlanticus occurred throughout the bay, and their densities and frequency of occurrence were lower in the northern part of the bay. In the southern part of the bay, stations in its southwest quadrant showed higher densities than the others. The larvae ofB. neonectabanus occurred only in the southern part of the bay in which stations in the northwest quadrant showed higher densities than the others.  相似文献   
98.
From three patients with pretibial myxedema (PTM) of Graves' disease, a portion of the skin involved was biopsied, analyzed for proteoglycans and the results were compared with those obtained with euthyroid and hyperthyroid subjects without PTM. The tissue specimen was extracted with 4 M guanidine HCl and subjected to subsequent CsCl density gradient centrifugation. Glycosaminoglycan and protein were recovered in the heaviest density fraction in the three specimens obtained from patients with PTM and not from subjects without PTM. From the analysis by Sepharose CL-6B column, glycosaminoglycan was present as a form of proteoglycan because alkaline borohydride treatment released single chain glycosaminoglycan with a molecular weight of 77,000 or 66,000. The digestion with chondroitin ABC lyase revealed that the majority of proteoglycan in the skin tissue was chondroitin sulfate or dermatan sulfate, and heparan sulfate comprised the minor component (14-34%). The rate of proteoglycan biosynthesis was examined by 35S incorporation into glycosaminoglycan's by cultured fibroblasts from PTM and normal skin. Incorporation of 35S into both proteoglycan and single chain glycosaminoglycan was observed in the fibroblasts of PTM patients as well as of those of subjects without PTM, although the rate of synthesis was more pronounced in the former. The rate of synthesis was influenced neither by normal serum or serum from a pretibial myxedema patient. Since proteoglycan accumulation was detected only in the affected skin of PTM patients, the impairment of local degradation and the proteoglycan clearance mechanism may also be involved.  相似文献   
99.
1. Serum levels of insulin-like growth factor-1 (IGF-1) in dairy cows declined after parturition, remained low during the period of early lactation with peak milk production and rose gradually until the end of lactation thereafter. 2. Growth hormone (GH) levels in sera of cows changed in parallel with milk yields. 3. Serum thyroxine and triiodothyronine levels during lactation remained fairly constant.  相似文献   
100.
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