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101.
D Parry  A Hextall  VP Robinson  NR Banner  MH Yacoub 《Canadian Metallurgical Quarterly》1996,51(11):1162-4; discussion 1164-5
Successful pregnancy in a single lung transplant recipient has not been reported previously. The long term effect of pregnancy on graft function and management of deteriorating pulmonary function is not defined. This case describes the management, outcome, and problems encountered when a single lung transplant recipient developed a progressive deterioration in pulmonary function during pregnancy, attributed to accelerated obliterative bronchiolitis.  相似文献   
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An ongoing goal of aesthetic surgery is a reduction in complications and an improvement in reproducibility and speed. Balloon dissector devices have been used in other areas of surgery to achieve these goals. This report presents early clinical experience using a balloon dissector to elevate the skin flap in facialplasty. The first step in the technique is the creation of a tunnel from a small preauricular incision toward the oral commissure using scissors dissection. The balloon device is inserted into this tunnel and inflated. Unrolling the device elevates the skin flap in the cheek and neck area. Retroauricular dissection and final adjustment of flap size and shape is completed sharply. Subsequent superficial musculoaponeurotic system flap development, skin redraping, and closure is performed in a conventional fashion after customary facialplasty incisions are made. Comparison of complications, postoperative drainage, and time required for dissection and for hemostasis was made between a balloon-dissected side and a conventionally dissected side in 10 patients undergoing facialplasty. Ten additional patients were treated with balloon dissection bilaterally. Patients ranged in age from 45 to 73 years. Mean balloon dissection time was 1.4 minutes (range, 0.75-4 minutes). This produced an even flap thickness in the correct plane with few if any bleeding points. Mean total dissection time on the balloon side was significantly shorter-13.6 minutes-compared with 27.8 minutes (p < 0.003) on the conventional side. Mean difference in time to hemostasis between conventional and balloon sides was 3.8 minutes (p < 0.001). Mean total postoperative drainage (all drains removed at 24 hours) was 13.8 cc on the balloon side and 18.8 cc on the conventional side (not significant, p=0.08). Less ecchymosis and swelling was observed on the balloon side compared with the scissors-dissected side. There were no skin losses, hematomas, infections, or nerve injuries on either side. Appearance of skin redraping was comparable on each side in all patients. Balloon dissection represents a promising alternative means of creating rapid, reproducible skin flap elevation in facialplasty, and is associated with a minimum of bleeding, ecchymosis, and swelling.  相似文献   
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Bipolar meiotic spindle formation without chromatin   总被引:1,自引:0,他引:1  
Establishing a bipolar spindle is an early event of mitosis or meiosis. In somatic cells, the bipolarity of the spindle is predetermined by the presence of two centrosomes in prophase. Interactions between the microtubules nucleated by centrosomes and the chromosomal kinetochores enable the formation of the spindle. Non-specific chromatin is sufficient, however, to promote spindle assembly in Xenopus cell-free extracts that contain centrosomes [1,2]. The mouse oocyte represents an excellent model system in which to study the mechanism of meiotic spindle formation because of its size, transparency and slow development. These cells have no centrioles, and their multiple microtubule-organizing centers (MTOCs) are composed of foci of pericentriolar material [3,4]. The bipolarity of the meiotic spindle emerges from the reorganization of these randomly distributed MTOCs [4]. Regardless of the mechanisms involved in this reorganization, the chromosomes seem to have a major role during spindle formation in promoting microtubule polymerization and directing the appropriate rearrangement of MTOCs to form the two poles [5]. Here, we examined spindle formation in chromosome-free mouse oocyte fragments. We found that a bipolar spindle can form in vivo in the absence of any chromatin due to the establishment of interactions between microtubule asters that are progressively stabilized by an increase in the number of microtubules involved, demonstrating that spindle formation is an intrinsic property of the microtubule network.  相似文献   
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The effects of traditional risk factors on low birth weight were examined, using logistic regression analyses and adjusting for interactions between multiple factors. Data for 11,936 births were obtained from a state birth cohort file. The effect for maternal ethnicity was dependent on education and marital status; the effect of marital status was dependent on ethnicity, medical risk, and level of prenatal care; and the effect of prenatal care was dependent on marital status. Results suggest that examining only main effects and ignoring interactions can produce overgeneralized conclusions about the influence of individual risk factors on low birth weight.  相似文献   
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Cytokines and insulin-like growth factors (IGFs) are involved in the induction and/or perpetuation of inflammatory bowel disease. The effect of fasting on inflammatory bowel disease was studied in a mouse experimental model of acute colitis caused by adding dextran sulfate sodium (DSS) to drinking water. Animals were either fed ad libitum or fasted (water only) for 2 days before death. Inflammation and tissue damage, measured as a colitis activity score, were markedly reduced in fasted (2.4 +/- 0.1) compared to fed (5.3 +/- 0.1) DSS animals (P < 0.0001). Colon interleukin-1 beta (IL-1 beta), IGF-I, and tumor necrosis factor-alpha messenger RNAs (mRNAs) were quantified by Northern blot hybridization and expressed as a percentage of mRNA abundance in fed controls. In DSS mice, IL-1 beta mRNA was elevated in the fed group (954 +/- 155%; P < 0.001), but was suppressed in fasted animals (71.1 +/- 11%). IGF-I mRNA also was elevated in fed DSS mice (421 +/- 71%; P < 0.01). This increase was attenuated in fasted DSS mice (202 +/- 17%; P < 0.01 compared to fed DSS mice). Tumor necrosis factor-alpha mRNA was increased in fed DSS mice (162 +/- 15%; P < 0.01), but was not significantly lower in fasted animals. By in situ hybridization, IL-1 beta mRNA was localized to the lamina propria of colonic mucosa in fed DSS animals, but was not detectable in other groups. We conclude that fasting has a protective effect on the progression of acute DSS, induced colitis. This is associated with decreased expression of IL-1 beta and IGF-I mRNAs in the colon.  相似文献   
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