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31.
Impact of smoking on cancer stage at diagnosis. 总被引:2,自引:0,他引:2
Nathan L Kobrinsky Marilyn G Klug Peggy Jo Hokanson Diane E Sjolander Larry Burd 《Journal of clinical oncology》2003,21(5):907-913
BACKGROUND: Studies evaluating the relationship between smoking and cancer spread are limited. METHODS: We studied the relationship between cancer stage at diagnosis (local, regional, or metastatic) and smoking history (current, previous, or nonsmoker). For lung cancer, patterns of spread were also studied. RESULTS: In a tumor registry for eastern North Dakota, northwestern Minnesota, and northern South Dakota, 11,716 cases were identified from 1986 to 2001. Current smokers (relative risk [RR], 2.11; 95% confidence interval, 1.93 to 2.32; P <.001) and previous smokers (RR, 1.56; 95% confidence interval, 1.42 to 1.72; P <.001) had an increased risk of metastatic disease at diagnosis. Current smokers (RR, 1.39; 95% confidence interval, 1.29 to 1.51; P <.001), but not previous smokers, also had an increased risk of regional disease. An increase in metastatic disease was most evident for prostate cancer (RR, 1.53; P =.003). An increase in regional disease was most evident for head and neck (RR, 3.53; P <.001), prostate (RR, 1.83; P =.030), and breast cancer (RR, 1.22; P =.005). Compared with previous smokers, current smokers with metastatic lung cancer were more likely to have involvement of the brain (33.6% v 23.0%; P =.004), bone marrow, adrenal gland, and pericardium (24.7% v 15.9%; P =.004). CONCLUSION: Previous or current smoking is a risk factor for increased cancer stage in a wide range of malignancies. Further study is required to determine whether this association is causal. 相似文献
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33.
J Moncada J Schachter G Bolan J Nathan M A Shafer A Clark J Schwebke W Stamm T Mroczkowski Z Seliborska 《Diagnostic microbiology and infectious disease》1992,15(8):663-668
A newly developed microwell enzyme immunosorbent assay (EIA) system by Syva Company (Palo Alto, CA) can detect Chlamydia trachomatis in < 3 hr. It uses a polyclonal antibody to chlamydial lipopolysaccharide and end points are determined with a spectrophotometer. Three clinical trial sites (University of California Medical Center, San Francisco, CA; University of Washington, Seattle, WA; and Louisiana State University Medical Center, New Orleans, LA), compared this EIA with tissue culture (TC) for identifying Chlamydia in urogenital specimens. Overall prevalence by TC was 10.4% (136 of 1306). When tests were compared with TC (using vials or microtiter plates and a fluorescent antibody stain), we found an EIA sensitivity of 93.4% (127 of 136) and a specificity of 98.1% (1148 of 1170). This EIA has a performance profile that is, at the very least, comparable with other nonculture methods for diagnosing genital tract infections with C. trachomatis. 相似文献
34.
This study was carried out to assess the efficacy of oral ondansetron, a new 5HT3 receptor antagonist, in patients undergoing thyroid surgery. It included 60 patients, randomly assigned to two groups, and receiving orally, 1 h before induction of anaesthesia, either 8 mg of ondansetron (n = 29) or a placebo (n = 30). One patient was excluded. The same anaesthetic protocol, consisting of 3 to 5 micrograms.kg-1 of fentanyl, 4 to 6 mg.kg-1 of thiopentone, and 0.5 mg.kg-1 of atracurium, was used in all. Anaesthesia was maintained with 50% nitrous oxide in oxygen with 0.8 to 1% endtidal concentration of isoflurane and additional boluses of 0.1 mg of fentanyl as required. The incidence and intensity of nausea, graded mild, moderate or severe, and the incidence of vomiting were recorded postoperatively. During the first twelve hours after surgery, 40% of patients in the placebo group had nausea (16.7% mild, 20% moderate and 6.7% severe), and 50% vomited. In the ondansetron group, nausea and vomiting occurred in 13.8% and 20.4% of patients respectively. The 4 patients in the latter group complained of major nausea. The differences between the groups were statistically significant: p = 0.025 for nausea and p = 0.042 for vomiting. It is concluded that oral ondansetron, 8 mg taken orally 1 h before surgery, significantly reduces the incidence of nausea and vomiting during the first twelve postoperative hours. As it is easy to use and has no side-effects, it might be of interest in day-case surgery patients, despite its high cost. 相似文献
35.
36.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
37.
J Brick P E Nathan E Westrick W Frankenstein A Shapiro 《Journal of studies on alcohol》1986,47(6):472-477
To determine whether the behavioral effects of alcohol were altered by menstrual cycle phase, 10 women between the ages of 21 and 24 who reported regular menstrual cycles of 28-31 days participated in three experimental sessions, the dates of which coincided with the flow, midcycle and premenstrual phases of their cycles. In each session, the effects of alcohol (.65 g/kg) were measured on memory for words, standing steadiness, coding vigilance and blood alcohol level (BAL). The following measures were obtained in each of three testing rounds: baseline, the ascending limb of the BAL curve and the descending limb of the BAL curve. Peak BALs of 83 +/- 2 mg/d1 were obtained. On coding vigilance, the subjects were observed to perform better during the flow phase of their cycle than they did in either the midcycle or premenstrual phase. No significant phase by alcohol effects were obtained, however. These results suggest that neither the pharmacokinetics of alcohol nor certain behaviors affected by alcohol were affected by menstrual cycle phase. These results are generally consistent with previous research, and they question the logic of excluding women subjects from studies on the effects of alcohol on behavior, at least for the variables used in this study. 相似文献
38.
Why is there a left side underestimation in rod bisection? 总被引:4,自引:0,他引:4
Subjects set the extremities of a horizontal rod to appear equidistant from a central reference point, with or without central fixation. On either side, the contrast (salience) of the rod against the background was high or low. Extents to the left were set smaller than those to the right, an effect (LSU) which was stronger with central fixation, indicating that both hemispatial and anatomical pathway factors contribute. Reduced salience on the left increased rather than decreased the LSU, indicating the importance of attentional factors. 相似文献
39.
Background: This study was conducted to investigate grading performance when estimating the severity of static versus dynamic images of contact lens‐related ocular pathology. Methods: Thirty‐eight subjects used the Efron Grading Scales for Contact Lens Complications to grade the severity of ocular pathological changes depicted in static and dynamic (movie clip) computer‐displayed images of each of the following contact lens complications: bulbar conjunctival redness, limbal redness, papillary conjunctivitis, corneal staining, corneal infiltrates and meibomian gland dysfunction. The viewing of static and dynamic images was separated by seven weeks. Results: Grades assigned to dynamic images were 0.6 and 0.7 grading scale units higher than those assigned to static images for limbal redness and papillary conjunctivitis, respectively (p < 0.0001 for both). No difference was observed for the other four complications. There was an apparent trend for grading variability to be reduced (that is, observers grading in closer agreement) when grading dynamic versus static images. Conclusions: Absolute grades based on an assessment of signs of pathology represented in static images may, in some instances, underestimate the true severity of the condition. 相似文献
40.
R S Elloway M P Jacobs M F Nathan J C Mantil 《European journal of nuclear medicine》1992,19(2):113-118
We combined edrophonium provocative testing with the technique of radionuclide oesophageal transit (RET) in 30 consecutive patients with non-cardiac chest pain (NCCP) and 12 controls. The oesophageal transit time of aqueous technetium-99m sulfur colloid was determined before and after intravenous infusion of 80 micrograms/kg edrophonium chloride (ED). Patient symptoms during provocative RET (P-RET) were recorded. Thirteen (43%) of the patients had abnormal study results, whereas all control subjects had normal results. Three groups considered abnormal were observed: (a) in two patients (6%), the pain was reproduced and transit pre- and post-ED administration was prolonged (greater than 15 s); (b) in six patients (20%), the pain was reproduced, but transit was normal pre- and post-ED; (c) in five patients (17%), transit pre- and post-ED was prolonged, but no pain was reproduced. In five patients (17%), ED prolonged the transit time greater than 15 s without pain, but the baseline transit was normal. Transit time was measurable in 23 patients. Mean pre-ED transit time was 10.2 +/- 7.4 s (mean +/- SD) and post-ED, 12.4 +/- 8.0 s (P = 0.3). We conclude that ED has no significant effect on transit time, and the pain induced by ED rarely correlates with an abnormal transit; P-RET provides additional information to baseline RET, increasing sensitivity, and may be a useful screening method in the evaluation of patients with NCCP. 相似文献