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101.
102.
103.
D C Birdsell G E Gavelin G M Kemsley K S Hein 《Plastic and reconstructive surgery》1981,68(5):742-745
An experiment was designed to compare the "holding power" or "staying power" of absorbable (polyglycolic acid and polyglactin 910) and nonabsorbable (nylon) suture. The aim of this experiment was to determine what provides the lasting strength of the bond between soft tissues that are approximated or plicated. When correcting the rectus diastasis during abdominoplasty, we used nylon sutures in 15 patients and absorbable synthetic sutures in 15 other patients. We then marked the closed folds of the rectus sheath with small metal vascular clips. Two days later and approximately 6 months after operation an upright anteroposterior abdominal x-ray was taken and the position of the metal clips was compared in the test groups. Although there was usually slight separation of the clips after 6 months, no significant difference between the two groups was noted, thereby indicating that holding power is not related to type of suture material but more likely to fibroplasia. 相似文献
104.
Revertants of Adenovirus Type 12-Transformed Hamster Cell Line T637 as Tools in the Analysis of Integration Patterns 总被引:8,自引:3,他引:5
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Spontaneously arising morphological revertants of the adenovirus type 12 (Ad12)-transformed hamster cell line T637 had been previously isolated, and it had been demonstrated that in these revertants varying amounts of the integrated Ad12 genome were eliminated from the host genome. In this report, the patterns of persistence of the viral genome in the revertants were analyzed in detail. In some of the revertant cell lines, F10, TR3, and TR7, all copies of Ad12 DNA integrated in line T637 were lost. In lines TR1, -2, -4 to -6, -8 to -10, and -13 to -16, only the right-hand portion of one Ad12 genome was preserved; it consisted of the intact right segment of Ad12 DNA and was integrated at the same site as in line T637. In revertant lines G12, TR11, and TR12, one Ad12 DNA and varying parts of a second viral DNA molecule persisted in the host genome. These patterns of persistence of Ad12 DNA molecules in different revertants supported a model for a mode of integration of Ad12 DNA in T637 hamster cells in which multiple (20 to 22) copies of the entire Ad12 DNA were serially arranged, separated from each other by stretches of cellular DNA. The occurrence of such revertants demonstrated that foreign DNA sequences could not only be acquired but could also be lost from eucaryotic genomes. There was very little, if any, expression of Ad12-specific DNA sequences in the revertant lines TR7 and TR12. Moreover, Ad12 DNA sequences which were found to be undermethylated in line T637 were completely methylated in the revertant cell lines G12, TR11, TR12, and TR2. These findings were consistent with the absence of T antigen from the revertant lines reported earlier. Hence it was conceivable that the expression of integrated viral DNA sequences was somehow dependent on their positions in the cellular genome. In cell line TR637, the early segments of Ad12 DNA were expressed and undermethylated; conversely, in the revertant lines G12, TR11, TR12, and TR2, the same segments appeared to be expressed to a limited extent and were strongly methylated. 相似文献
105.
Estrogen dependent ciliogenesis in the chick oviduct 总被引:1,自引:0,他引:1
Both the hormone dependency and the morphological details of estrogen-dependent ciliogenesis in the shell gland of the chick oviduct were investigated. Ciliogenesis was initiated on day 3 of estrogen treatment, and progressively more cells became differentiated until, on day 10, 55% ciliation occurred with 17-estradiol (1 mg/day) and 75% ciliation occurred with diethylstilbestrol (1 mg/day). Simultaneous administration of progesterone with diethylstilbestrol (1 mg each/day for 10 days) caused a 50% depression in the number of ciliated cells on day 10. The rate of ciliogenesis was found to be affected by progesterone and the type of estrogen administered. The minimum stimulatory dose of estradiol was found to be between 0.01 mg/day and 0.05 mg/day. Ciliogenic cells were first recognized by the appearance of pro-basal bodies in the apical portion of the cell. Pro-basal body maturation and cilium formation were the same as those described for the chick trachea. Ciliogenesis in the chick was found to be homologous to estrogen-dependent ciliogenesis in various mammalian oviducts. 相似文献
106.
H E Hein 《Experimental parasitology》1975,38(3):271-278
Young chickens inoculated with multiple low doses of mixed oocysts of Eimeria acervulina, E. brunetti, and E. maxima had a high level of resistance to reinfection with a mixed challenge dose on Day 28, Day 84, or Day 140. Immunity was enhanced when the number of immunizing doses was increased from three to four. Resistance was also high in birds maintained on a proprietary mixture of amprolium, ethopabate, and sulphaquinoxaline (Pancoxin-Merck, Sharp and Dohme Ltd.) during immunization, although immunity to E. acervulina was lower in these birds. Oocyst production was lower in birds given mixed infections as compared with that of birds given pure infections with similar doses of oocysts. Competition between species did not inhibit the development of immunity in birds given low doses of mixed oocysts. 相似文献
107.
Helen E. Hein 《Experimental parasitology》1976,40(2):250-260
Resistance to reinfection varied with the species of Eimeria and with the number of oocysts in the inoculum. Chickens immunized with doses of 20,000 and 80,000 oocysts of E. acervulina, 312 and 1250 oocysts of E. brunetti or E. necatrix, or 1250 and 5000 oocysts of E. maxima at 2 and 4 weeks of age, respectively, were almost completely immune to a challenge dose at 6 weeks of age. Resistance was slightly less in chickens immunized with 1250 and 5000 oocysts of E. acervulina or 312 and 1250 oocysts of E. maxima. Birds given three immunizing infections of 1250, 5000, and 20,000 oocysts of E. maxima were completely immune 8 weeks after the last dose. Resistance was slightly less in birds immunized with similar doses of E. brunetti or E. necatrix. Doses of 20,000, 80,000, and 320,000 oocysts appeared necessary to confer a high level of immunity to E. acervulina. More than three low doses of oocysts appear necessary to induce a complete and enduring immunity against a high challenge for E. acervulina, E. brunetti, and E. necatrix. Higher immunizing doses would not be satisfactory due to the pathogenic effects of the coccidia after the initial infection. 相似文献
108.
109.
Madritsch Silvia Bomers Svenja Posekany Alexandra Burg Agnes Birke Rebekka Emerstorfer Florian Turetschek Reinhard Otte Sandra Eigner Herbert Sehr Eva M. 《Plant molecular biology》2020,104(4-5):379-380
Plant Molecular Biology - In the above mentioned publication, part of Fig. 6B was distorted (extra diagonal lines appeared). The original article has been corrected and the proper version... 相似文献
110.
K D Hein M E Wechsler R M Schwartzstein D J Morris 《Plastic and reconstructive surgery》1999,103(6):1706-1708
Adult respiratory distress syndrome occurred in a patient who had received dextran as a routine antithrombotic agent during and after free TRAM breast reconstruction. Although most patients who receive dextran have no adverse reaction, particularly after hapten inhibition by dextran 1 infusion, the serious nature of this complication in an elective operation calls into question the continuing routine use of dextran in microsurgery. 相似文献