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81.
Cytogenetic and molecular genetic analysis of tumorigenic human bronchial epithelial cells induced by radon alpha particles 总被引:4,自引:1,他引:4
To establish a cell culture model for lung carcinogenesis, independent
populations of the human papillomavirus 18-immortalized human bronchial
epithelial cell line BEP2D were treated with high linear energy transfer
radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu
mice. Six independent cell lines were established from tumors that
developed from three separate radiation treatments as follows: treatment
(Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L,
R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1.
Cytogenetic analysis revealed common changes in all tumor lines: loss of
the Y chromosome (ch), one of three copies of ch8, one of three copies of
ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of
polymerase chain reaction-amplified short tandem repeats of informative
loci confirmed the loss of chY in all lines and loss of heterozygosity
(LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and
2. Our data support previous studies indicating the presence of tumor
suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in
all cell lines from Tx 2 and in one of two lines from Tx 3. This region,
14q12-q13, may contain changes in one of the five known somatostatin
receptor genes (SSTR1). No LOH was detected at any of the informative loci
tested for on ch4 or ch11.
相似文献
82.
HM Goodyear JC Moore-Gillon EH Price VF Larcher MO Savage CB Wood 《Archives of disease in childhood》1993,69(2):229-231
Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition. 相似文献
83.
84.
Hale JD; Valk PE; Watts JC; Kaufman L; Crooks LE; Higgins CB; Deconinck F 《Radiology》1985,157(3):727-733
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image. 相似文献
85.
86.
BACKGROUND: Although rarely life-threatening, postoperative vomiting (POV) is a distressing complication. The incidence of POV ranges from 34 to 90% in children undergoing strabismus surgery when antiemetics are not administered prophylactically. METHODS: In this study, a cost-consequence analysis (CCA) is used to estimate the economic benefit of ondansetron and dimenhydrinate as antiemetics administered prophylactically in children undergoing strabismus surgery. This retrospective study was conducted at The Hospital for Sick Children based on a review of 70 charts. RESULTS: Ondansetron was more effective with 45.3 POV-free patients (PFP) in an adjusted cohort of 100, while dimenhydrinate resulted in 38.2 PFP in an adjusted cohort of 100. The costs were significantly different between the two groups, CAD dollars 185.90 (+/-26.37, 95% CI, CAD dollars 173,89; CAD dollars 197.90) and CAD dollars 232.90 (+/-CAD dollars 66.84, 95% CI, CAD dollars 198.53; CAD dollars 267.27) per patient for ondansetron and dimenhydrinate, respectively. The length of stay in the postanesthetic care unit (PACU) represented over 97% of total costs, and the mean lengths of stay in the PACU for ondansetron and dimenhydrinate were significantly different, 3.43 and 4.41 h, respectively. CONCLUSION: This study should serve as a pilot for a large-scale investigation on the correlation between the length of stay in the PACU and the antiemetic agent used. 相似文献
87.
Garbay JR Picone O Baron-Merle G Yacoub S Lasry S Missana MC Barreau-Pouhaer L Fourchotte V Cavalcanti A Thoury A 《Gynécologie, obstétrique & fertilité》2004,32(12):1039-1046
OBJECTIVE: Axillary padding without drainage appeared to be a valuable alternative technique to vacuum drainage. The technique employs local muscles or the axillary aponeurosis for padding. We report here the clinical evaluation of muscular padding without drainage. The analysis of these results prompted us to also do a literature search for other alternatives aimed at reducing morbidity due to vacuum drainage. PATIENTS AND METHODS: Muscular padding was prospectively performed by 8 different surgeons on a total of 152 patients at the Centre Rene-Huguenin (Saint-Cloud, France). Follow-up has attained 3.5 years. A comparative assessment of pain was conducted in 30 patients operated on with vacuum drainage. RESULTS: This technique is easy to learn and reproducible. It facilitates post-operative follow-up, always allowing discharge at the 2nd or 3rd post-operative day without any home nursing. The late sequels are not increased. In contrast, pain was twice more intense during the first post-operative weeks compared with vacuum drainage, and the seroma rate was also increased. DISCUSSION AND CONCLUSION: Despite good efficacy, this worsening of pain is a major obstacle to the routine use of muscular padding. A technical improvement has been published very recently where the axillary aponeurosis was used to pad the axilla. It seems to be equally efficient but less painful than muscular padding. This technique is under clinical evaluation and could appear as a valuable option to vacuum drainage. Other alternatives are discussed. Most studies lack a direct comparison with vacuum drainage and a satisfactory evaluation of quality of life is also omitted. New studies with quality of life scales are ongoing. They should allow us to choose options that take this aspect into account in the future. 相似文献
88.
89.
OBJECTIVE: To determine whether children's food consumption is increased by the size of the group of children in which they are eating. DESIGN: Crossover study. SETTING: University based preschool. PARTICIPANTS: 54 children, aged 2.5-6.5 years. INTERVENTIONS: Each child ate a standardised snack in a group of three children, and in a group of nine children. MAIN OUTCOME MEASURES: Amount each individual child consumed, in grams. RESULTS: Amount eaten and snack duration were correlated (r = 0.71). The association between group size and amount eaten differed in the short (<11.4 min) versus the long (> or =11.4 min) snacks (p = 0.02 for the interaction between group size and snack duration). During short snacks, there was no effect of group size on amount eaten (16.7 (SD 11) g eaten in small groups vs 15.1 (6.6) g eaten in large groups, p = 0.42). During long snacks, large group size increased the amount eaten (34.5 (16) vs 26.5 (13.8), p = 0.02). The group size effect was partially explained by a shorter latency to begin eating, a faster eating rate and reduced social interaction in larger groups. CONCLUSIONS: Children consumed 30% more food when eating in a group of nine children than when eating in a group of three children during longer snacks. Social facilitation of food consumption operates in preschool-aged children. The group size effect merits consideration in creating eating behaviour interventions. 相似文献
90.
Dissemination risk index based on plasminogen activator system components in primary breast cancer. 总被引:2,自引:0,他引:2
C Bouchet K Hacène P M Martin V Becette M Tubiana-Hulin S Lasry J Oglobine F Spyratos 《Journal of clinical oncology》1999,17(10):3048-3057
PURPOSE: To study interactions between disease-free survival (DFS) and four components of the plasminogen activator system: urokinase-type plasminogen activator (uPA), its two inhibitors (PAI-1 and PAI-2), and its membrane receptor uPAR. PATIENTS AND METHODS: We conducted a retrospective study of 499 primary breast cancer patients (median follow-up, 6 years). uPA, PAI-1, and PAI-2 were determined on cytosols and uPAR on solubilized pellets, using enzyme-linked immunoadsorbent assay kits (American Diagnostica, Greenwich, CT). Classical univariate and multivariate statistical methods were used together with multiple correspondence analysis to graphically examine interactions between the variables and outcome. RESULTS: By univariate analysis, higher uPA and PAI-1 values were significantly related to shorter DFS (P =.002; P <.00002). PAI-2 was not significantly related to DFS, although patients with high and very low PAI-2 values had a longer DFS. Multiple correspondence analysis showed the parallel impact of uPA and PAI-1 on outcome, and the clearly different behavior of PAI-2 compared with PAI-1. The prognostic contribution of uPAR seemed weak by both methods. A dissemination risk index [uPA x PAI-1/(PAI-2 + 1)], taking into account the modulation of uPA proteolytic activity by the ratio of its two inhibitors, was then tested. Dissemination risk index was selected as an independent variable in the Cox model in the overall population (P <.000001) and in node-positive patients (P <.00001). It was the only variable selected in node-negative patients (P =. 003). CONCLUSION: A dissemination risk index determined on primary tumor and taking into account the different effects of PAI-1 and PAI-2 on uPA can be of major help in clinical management of breast cancer, particularly in node-negative patients. 相似文献