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The aim of the study was to assess the role of pathological grade, cell proliferation, ploidy, immunophenotype and site in determining the prognosis of non-Hodgkin's lymphomas. Of particular interest was the relative value of grades derived from the Kiel classification as opposed to the National Cancer Institute (NCI) working formulation. The study consisted of 181 cases, treated in a relatively uniform way over an 18-month period spanning 1986. Using life table analysis, both NCI working formulation grade and Kiel grade correlated strongly with survival. However, the differences between grades were entirely due to an excess of early deaths in the high-grade and intermediate-grade categories. In patients surviving greater than 0.1 years (37 days), phenotype, site, ploidy and cell proliferation had no effect on survival. There was no evidence that intermediate-grade tumours, when subdivided into Kiel low- and high-grade types, differed in survival from tumours graded as low- or high-grade by both methods. However, NCI working, formulation high-grade tumours, especially those with a high proliferation rate, formed a group with a very high likelihood of death within 0.1 years.  相似文献   
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Historically, the healing of tracheal or bronchial anastomoses has been the Achilles heel in pulmonary transplantation. In the past, steps taken to enhance healing of these structures and have allowed single-lung, double-lung, and heart-lung transplantation to be accomplished safely. This report presents a simplified technique for protection of the tracheal anastomosis in heart-lung and double-lung transplantation. This technique, wherein the pericardial fat pad from the right side is utilized to wrap the tracheal anastomosis, not only allows for excellent healing of the anastomosis but separates the aorta from the trachea. In 19 patients having heart-lung (N = 13) or double-lung (N = 6) transplantation there were no tracheal healing problems, dehiscence or stenosis found.  相似文献   
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To identify subgroups of smokers with different success rates, we applied "tree-structured survival analysis" (TSSA) to data from a previously published trial of transdermal nicotine. The subjects who received active treatment (14 mg patch, n 275, or the 21 mg patch, n 262) constituted the sample for this analysis. Using age, gender, the Fagerstrom Tolerance Questionnaire (FTQ), motivation to quit, number of cigarettes smoked at baseline, and body mass index (BMI) as classification variables, TSSA identified two subgroups within the 14 mg patch group and four subgroups of smokers within the 21 mg patch group. Among those receiving the 14 mg patch, individuals with a BMI greater than 26.4 kg/m relapsed sooner than did those with a BMI less than or equal to this value. Within the 21 mg patch group, the survival curve for males was significantly different from that observed in females, with males experiencing a longer time to relapse after treatment than did females. Among males, those who were less dependent relapsed significantly later than did those men who were more dependent. Among females, those with a higher motivation to quit relapsed more slowly than did those women with less motivation to quit. This information may be helpful to clinicians seeking to match specific patients to specific treatments with transdermal nicotine in order to maximize treatment outcomes.  相似文献   
6.
Subchronic Oral Toxicity Study of Diisopropyl Methylphosphonate in Mink   总被引:1,自引:0,他引:1  
Diisopropyl methylphosphonate (DIMP), produced during manufactureof the chemical agent GB (Sarin), is a groundwater contaminantat Rocky Mountain Arsenal, Colorado. DIMP was fed for 90 daysto dark brown "Ranch Wild" mink housed under controlled indoorconditions. One-year-old mink, 10 of each sex, were fed 0, 50,450, 2700, 5400, or 8000 ppm in standard ranch diet. ActualDIMP consumption was 0, 8, 73, 400, 827, and 1136 mg/kg bodywt/day, respectively. Two additional groups of 10 served as"pair-fed" controls. Body weight and food intake were recordedweekly. Complete blood count and 15 chemical analytes were measuredat Weeks 0, 3, 7, and 13. Necropsy and microscopic examinationwere performed on all mink. No clinical morbidity or deathsoccurred. Both sexes fed 8000 ppm ate approximately 20% lessand weighed approximately 20% less than the controls; 5400 ppmfemales had a 10% weight decrement. Plasma cholinesterase (ChE)decreased in the top three dose groups starting at Week 3. At13 weeks, decrements were approximately 50% but returned tonormal after 1 week without DIMP. Erythrocyte ChE was not reduced.Heinz bodies occurred in 10–15% of RBCs in 50% of 8000ppm mink at 13 weeks, and 0.1–2.0% of RBCs in 25% at 2700ppm. There were mild decreases in RBC count, hematocrit, andhemoglobin, and increases in reticulocyte count, at the 5400and 8000 ppm doses. All recovered within 3 weeks after DIMPwas with drawn. The 8000 ppm group had marginal splenic hematopoiesis,histologically. No other treatment-related changes were noted.The 450 ppm dose was a clear no-effect level (approximately73 mg DIMP/kg body wt/day). Compared to reports of similar studiesof DIMP in rats and dogs, these mink displayed no unique speciessusceptibility.  相似文献   
7.
To address the assumption of clonally restricted antibodies in immune thrombocytopenias we studied sera from 19 patients with chronic ITP known to possess antibodies reactive with glycoprotein (GP) Ib/IX and/or GPIIb/IIIa. These sera were re-analysed using the standard monoclonal antibody immobilization of platelet antigens (MAIPA) assay and 16 patients exhibited IgG antibodies reactive with GPIIb/IIIa; seven patients showed also a reactivity with GPIb/IX. Employing a light-chain-specific MAIPA assay, 75% (12/16) of these sera displayed GPHb/ Ilia-specific antibodies that were light chain restricted; only 13% (2/16) of the GPIIb/IHa reactive sera showed a mixed kappa and lambda phenotype. A light-chain-restricted phenotype was also seen for the GPIb/IX reactive antibodies. To further substantiate these findings, the MAIPA assay was modified in order to avoid interference from human anti-mouse antibodies. A high frequency of light-chain restricted platelet antibodies was also found using the modified MAIPA technique. These results support the hypothesis of a clonal B-cell expansion in immune thrombocytopenias, producing antibodies with a restricted idiotype repertoire and reacting with a limited number of epitopes.  相似文献   
8.
The Zucker rat is used as a model of genetic obesity, and while Zucker rats have been well studied for their reduced sensitivity to leptin signaling and subsequent weight gain, little work has examined their responses to environmental signals that are associated with “hedonic” feeding. This study evaluated the effects of a high‐fat food olfactory cue (bacon) in stimulating nose‐poke food‐seeking behavior on first exposure (novel) and after a period of access for consumption (familiar) in lean and obese Zucker rats at either 4 or 12 months of age, and under ad‐lib fed (unrestricted; U) or chronically food‐restricted (70% of ad‐lib; R) conditions. Baseline nose‐poke levels were comparable amongst all groups. At 4 months of age, only ObU rats displayed increased behavioral activation to familiar food cues. Twelve‐month‐old Ob rats, regardless of diet, exhibited substantially greater food‐seeking behavior when exposed to both the novel and familiar olfactory cues. A strong positive correlation between body weight and nose‐poke entries for the familiar food cue was observed at both ages, while this correlation for the novel food cue was significant in 12–month‐old rats only. Similarly, there were strong positive correlations between food intake and poke entries for the familiar food cue was observed at both ages, while this correlation for the novel food cue was significant in 12–month‐old rats only. Although it is possible that differences in olfactory sensitivity contribute to these behavioral effects, our findings support the interactions between food intake, obesity, and food‐seeking behavior and are consistent with leptin inhibiting the brain's reactivity to food cues and suggest that the enhanced sensitivity to the food cues with leptin deficiency is likely to contribute to overeating and weight gain. Synapse, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
9.
PURPOSE: Congenital anterior urethrocutaneous fistula is a rare anomaly that may present in an isolated fashion or in association with other penile abnormalities, such as chordee or hypospadias. There have been 18 cases of congenital anterior urethrocutaneous fistula reported in the literature. We present 14 additional cases of congenital anterior urethrocutaneous fistula. MATERIALS AND METHODS: We treated 14 patients with congenital anterior urethrocutaneous fistula, of whom 9 were uncircumcised at presentation. Two patients had evidence of chordee and 4 had distal hypospadias. RESULTS: The type of repair was determined by the anatomical variations of this anomaly. All cases were corrected electively by various techniques based on the degree of the defect, including primary closure via a Thiersch-Duplay urethroplasty, pedicle flap urethroplasty, hinged flap urethroplasty and interpositioned island pedicle tube or onlay urethroplasty. CONCLUSIONS: To our knowledge the embryological events that cause anterior urethrocutaneous fistula are unclear but they likely result from a defective urethral plate or an abnormality of the infolding of the urethral groove. Surgical technique must be individualized to fit the defect. While there has been considerable skepticism regarding the existence of congenital urethrocutaneous fistula, the fact that 9 of our 14 patients were uncircumcised confirms the congenital nature of this lesion.  相似文献   
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