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101.
Robert A. Schnoll Ph.D. James Calvin B.A. Michael Malstrom B.S. Randi L. Rothman B.A. Hao Wang M.S. James Babb Ph.D. Suzanne M. Miller Ph.D. John A. Ridge M.D. Ph.D. Benjamin Movsas M.D. Corey Langer M.D. Michael Unger M.D. Melvyn Goldberg M.D. 《Annals of behavioral medicine》2003,25(3):214-221
Even though continued smoking by cancer patients adversely affects survival and quality of life, about one third of patients
who smoked prior to their diagnosis continue to smoke after their diagnosis. The implementation of smoking cessation treatments
for cancer patients has been slowed by the lack of data on correlates of tobacco use in this population. Thus, this longitudinal
study assessed demographic, medical, addiction, and psychological predictors of tobacco use among 74 head, neck, and lung
cancer patients. Multivariable binary logistic regression analyses, with outcome categorized as smoker or nonsmoker, indicated
that the likelihoodthat patients would be a smoker was associated with lower levels of perceived risk and a higher level of
quitting cons. Multivariable nominal logistic regression, with outcome classified as continuous smoker, continuous quitter,
relapser, or follow-up quitter, indicated that: (a) patients categorized as continuous smokers reported significantly lower
quitting self-efficacy than follow-up quitters and continuous quitters, (b) relapsers reported a significantly lower level
of quitting self-efficacy than either follow-up quitters or continuous quitters, and (c) continuous smokers exhibited a significantly
lower level of risk perceptions than continuous abstainers. These findings can be useful for the development and evaluation
of treatments to promote smoking cessation among cancer patients.
Support for this study was provided by National Institutes of Health Grants CA57708, CA06927, CA88610, CA95678, and CA76644. 相似文献
102.
One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the
amount of capsular contraction was found much less than when similar ``slick' prostheses were used. Another advance was their
fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were
moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of
the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been
that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced. 相似文献
103.
Comparison of hand-sewn and stapled esophagogastric anastomosis after esophageal resection for cancer: a prospective randomized controlled trial. 总被引:14,自引:0,他引:14
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OBJECTIVE: The objective of this study was to compare the hand-sewn and stapled methods in esophagogastric anastomosis. SUMMARY BACKGROUND DATA: After esophageal resection for cancer, the relative merits of the hand-sewn and the stapled methods of esophagogastric anastomosis, especially regarding leakage and stricture rates, have not adequately been studied. METHODS: A prospective randomized controlled trial was undertaken in 122 patients with squamous cell cancer of the thoracic esophagus who underwent a Lewis-Tanner esophagectomy. Patients were stratified according to esophageal size, based on the diameter of the divided esophagus (< or > or = 30 mm) and then were randomized to have either a hand-sewn or a stapled anastomosis. RESULTS: The mean total operating times (standard error of the mean) when the hand-sewn and the stapled methods were used were 214 (4) minutes and 217 (3.4) minutes, respectively (p = not significant [NS]). The respective in vivo proximal resection margins (standard error of the mean) were 8 (0.4) cm and 7.6 (0.4) cm (p = NS). Leakage rates were 1.6% and 4.9% (p = NS). Excluding hospital deaths, patients with leakage or anastomotic recurrence, and those who received radiation therapy to histologically infiltrated resection margin, anastomotic stricture was found in 5 (9.1%) of 55 patients in the hand-sewn group and 20 (40%) of 50 in the stapler group (p = 0.0003). The difference in stricture rates was significant in small as well as large esophagi. Anastomotic recurrence developed in only one patient in each group. CONCLUSIONS: The authors conclude that both methods were safe, but the stapled technique resulted in more stricture formation. 相似文献
104.
105.
106.
无创性动态血压(ABPM)能较客观地反映血压水平及其昼夜变化规律,对高血压病的诊断、指导用药、药物疗效的评定以及预后评估等均有较大价值。本文对ABPM的发展及临床应用等问题进行综述。 相似文献
107.
108.
A system for assaying homologous recombination at the endogenous human thymidine kinase gene.
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M B Benjamin H Potter D W Yandell J B Little 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(15):6652-6656
A system for assaying human interchromosomal recombination in vitro was developed, using a cell line containing two different mutant thymidine kinase genes (TK) on chromosomes 17. Heteroalleles were generated in the TK+/+ parent B-lymphoblast cell line WIL-2 by repeated exposure to the alkylating nitrogen mustard ICR-191, which preferentially causes +1 or -1 frameshifts. Resulting TK-/- mutants were selected in medium containing the toxic thymidine analog trifluorothymidine. Mutations were characterized by exon-specific polymerase chain reaction amplification and direct sequencing. In two lines, heterozygous frameshifts were located in exons 4 and 7 of the TK gene separated by approximately 8 kilobases. These lines undergo spontaneous reversion to TK+ at a frequency of less than 10(-7), and revertants can be selected in cytidine/hypoxanthine/aminopterin/thymidine medium. The nature and location of these heteroallelic mutations make large deletions, rearrangements, nondisjunction, and reduplication unlikely mechanisms for reversion to TK+. The mode of reversion to TK+ was specifically assessed by DNA sequencing, use of single-strand conformation polymorphisms, and analysis of various restriction fragment length polymorphisms (RFLPs) linked to the TK gene on chromosome 17. Our data suggest that a proportion of revertants has undergone recombination and gene conversion at the TK locus, with concomitant loss of frameshifts and allele loss at linked RFLPs. Models are presented for the origin of two recombinants. 相似文献
109.
110.
H. W. Chu S. Balzar J. Y. Westcott J. B. Trudeau Y. Sun D. J. Conrad S. E. Wenzel 《Clinical and experimental allergy》2002,32(11):1558-1565
BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels. 相似文献