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71.
72.
Contingent reinforcement for reduced breath carbon monoxide levels: Target-specific effects on cigarette smoking 总被引:1,自引:0,他引:1
This study determined the effects on smoking behavior of providing contingent reinforcement for nonsmoking versus reduced smoking afternoon breath carbon monoxide (CO) target levels. Twenty-eight hired chronic smoker volunteers were randomly assigned to one of three experimental conditions during a 10-day intervention: (a) 8 ppm target CO, $5 per day incentive (n = 11); (b) 16 ppm target CO, $4 per day incentive (n = 8); or (c) 8 ppm target CO, no incentive (n = 9). Both payment groups showed significantly lower CO levels and greater amounts of daytime smoking reduction than the no-pay group. A specific effect of CO target was also seen; 45% of subjects in the 8 ppm group compared with 0% of subjects in the 16 ppm target and no-pay groups produced average afternoon CO levels of 8.5 ppm or lower during the intervention. Average levels of CO and smoking reduction did not differ for the two paid groups, however, because some subjects in the 8 ppm group failed to reduce CO sufficiently to contact the reinforcer. Contingent reinforcement based on expired air CO levels can exercise powerful and precise (target-specific) control over smoking behavior, but there may be individual differences in ability to meet reinforcement contingencies if difficult targets are introduced abruptly. 相似文献
73.
The adsorption of quinidine onto kaolin was studied as a function of pH in aqueous solutions in which the ionic strength was adjusted to 0.1. The interaction of quinidine with pectin also was investigated in water and in phosphate buffer; the buffer pH and ionic strength were adjusted to 6.5 and 0.1, respectively. The in vitro results indicated that quinidine was adsorbed onto kaolin. At the highest concentration studied, the extent of adsorption increased from 3.64 mg of quinidine adsorbed/g of adsorbent at pH 2.4 to an average of 5.81 mg/g in the pH 5.5-7.5 range. In the presence of electrolytes, the interaction of quinidine with pectin was relatively small (3-13% bound) as compared to studies performed in water (66-90% bound). The data indicate that some quinidine may be adsorbed when this drug is administered concurrently with kaolin-pectin preparations. 相似文献
74.
Liu W Hill D Gibbs AF Tempany M Howe C Borland R Morand M Kelly JW 《Melanoma research》2005,15(6):549-554
The ABCD(E) rule and the seven-point checklist are diagnostic aids that have proven to be useful in the hands of physicians; however, little is known of their value to patients with respect to aiding self-detection. The objective of this study was to investigate features that patients notice when identifying melanomas and to explore how well these features correspond to the ABCD(E) rule and the seven-point checklist. A retrospective, modified, case-control study involving patient interviews was performed. All interviews were conducted through the private consulting rooms of a Melbourne dermatologist (JWK) and a Newcastle plastic surgeon (CH) prior to the result of pathology being known to the patients and the interviewers. Sixty-seven patients with benign pigmented skin lesions and 46 patients with melanomas were included. Using a logistic regression model, the change in size/new lesion and change in colour (major criteria, seven-point checklist) were most useful in differentiating between melanomas and benign pigmented lesions in the hands of patients [odds ratio (OR), 4.74; 95% confidence interval (CI), 1.85-12.19; P=0.001; OR, 4.27; 95% CI, 1.62-11.26; P=0.003, respectively). The ABCD(E) rule failed to discriminate between melanoma and other benign pigmented skin lesions. It can be concluded that, of the patients' observations, changes in size or colour were most important in distinguishing between benign pigmented lesions and melanomas. Such features therefore deserve emphasis in public education campaigns. Medical professionals should also remember to seek a history of change in assessing pigmented skin lesions. 相似文献
75.
Long-term breast cancer survivors' use of complementary therapies: perceived impact on recovery and prevention of recurrence 总被引:2,自引:0,他引:2
OBJECTIVE: Many cancer survivors use some form of complementary therapy (CT); this is particularly true for women with breast cancer. The majority of reports on CT use in women with breast cancer have focused on CT use during cancer treatment or within a year or two of treatment completion. The purpose of this study was to evaluate longer-term breast cancer survivors' (average, 8.7 years) frequency of CT use and their beliefs about the role of CT in cancer recovery and the prevention of cancer recurrence, as well as the relationship of CT use with current life satisfaction. METHODS: A mail survey was completed by 608 breast cancer survivors a minimum of 2 years after their most recent cancer diagnosis. Participants were contacted through the American Cancer Society Reach to Recovery program in Florida. The self-report questionnaire inquired about the use of various CTs, beliefs about CT, current life satisfaction, demographic characteristics, and cancer treatment history. RESULTS: Most of the respondents were older than 50, were Caucasian, were married, had attended or completed college, and were at least 5 years after breast cancer treatment. The most commonly used CTs included exercise, vitamins, prayer/spiritual practice, support groups, humor, self-help books, and relaxation. These survivors used CT therapies because they wanted to play a more active role in their cancer recovery, to manage stress, and to maintain hope. A majority of them reported that they used CT to reduce the risk of cancer recurrence. Use of CT was not correlated with life satisfaction. CONCLUSIONS: Most of the breast cancer survivors in this study had used some form of CT since the time of their most recent cancer diagnosis and believed that such therapies could be of significant benefit, despite a lack of correlation between CT use and current life satisfaction. Many believed that use of CT may prevent cancer recurrence. It is important, therefore, to investigate the efficacy of various CTs among longer-term cancer survivors, especially with regard to their potential in preventing cancer recurrence. 相似文献
76.
BACKGROUND: The number of fluctuations in the skin conductance per s (NFSC) as a measure of the sympathetic nervous system may be a tool for monitoring physiological stress during surgery and general anaesthesia. The purpose of this study was to find the sensitivity and specificity of the NFSC when compared to a peroperative clinical stress score. Moreover, different patterns of skin conductance responses were compared with the BIS score to find out if the mean level of skin conductance (SC) and NFSC monitoring could differentiate between awakening and noxious stimuli. METHODS: Fourteen patients were studied during stressful or non-stressful registration periods. During each registration period, the NFSC was compared to a five-point clinical stress score (CSS) (systolic blood pressure >130 mmHg, cough, tears, EMG in the forehead >50 or movements) and BIS score. RESULTS: The NFSC and the CSS both indicated physiological stress at 12 registrations and no stress at 186 registrations. The NFSC indicated physiological stress without signs of clinical stress (CSS = 0) in 28 registrations, whereas signs of clinical stress (CSS > 0) were indicated on two occasions without signs of stress in the NFSC. The sensitivity of the NFSC when compared to the CSS was 86% and the specificity was 86%. Moreover, in all situations (n = 16) where NFSC indicated stress and the BIS score >50, the SC increased. This was different from situations (n = 13) where NFSC indicated stress and the BIS score <50, then the SC did not increase (P < 0.001). CONCLUSION: The NFSC is sensitive to clinical stress during surgical stimulation. Moreover, the combined use of SC and NFSC may have a potential to differentiate between situations of stress due to inadequate hypnotic effect vs. inadequate analgesic effect. 相似文献
77.
Cumberbatch Z Copersino M Stitzer M Jones H 《The American journal of drug and alcohol abuse》2004,30(2):237-249
Drug treatment-seeking abusers generally self-select their treatment modality. Most opioid-dependent individuals select either methadone maintenance or detoxification followed by medication-free outpatient treatment. This study examined demographic, drug use, and drug abuse treatment history for opioid dependent patients entering an opioid agonist (n = 203) or a medication-free (n = 155) treatment program located on the same hospital campus. Similar demographic profiles support the assertion that samples were drawn from the same inner city urban opioid using population. Patients entering drug-free treatment, however, reported more extensive prior use of both cocaine and alcohol. Further, these patients had a generally more severe profile of psychosocial problems in medical, legal, employment, family/social, and psychiatric areas as measured by the Addiction Severity Index (ASI). These findings suggest that outpatient drug-free programs enrolling opioid abusers are faced with a unique service delivery challenge that involves service needs in multiple arenas. The findings further suggest that patient self-selection of treatment programs may in some cases result in a discrepancy between patient needs and the ability of treatment programs to retain patients and deliver an appropriate array of services. 相似文献
78.
79.
Comparison of conventional bacteriology with nucleic acid amplification (amplified mycobacterium direct test) for diagnosis of tuberculous meningitis before and after inception of antituberculosis chemotherapy 下载免费PDF全文
Thwaites GE Caws M Chau TT Dung NT Campbell JI Phu NH Hien TT White NJ Farrar JJ 《Journal of clinical microbiology》2004,42(3):996-1002
The role of nucleic acid amplification techniques in the rapid diagnosis of tuberculous meningitis remains uncertain. We compared the performance of Ziehl-Neelsen (ZN) staining, the Gen-Probe amplified Mycobacterium tuberculosis direct test (MTD), and culture with 341 cerebrospinal fluid specimens from 152 adults (73 with and 79 without tuberculous meningitis) before and after inception of antituberculosis chemotherapy. The sensitivity, specificity, and positive and negative predictive values of ZN staining before treatment were 34/66 (52%), 79/79 (100%), 34/34 (100%), and 79/111 (71%), compared with 25/66 (38%), 78/79 (99%), 25/26 (96%), and 79/120 (66%) for MTD. The sensitivity of combined ZN staining and MTD (either positive) was 45/66 (68%). The sensitivity of staining and culture fell more rapidly than that of MTD after the start of treatment: after 5 to 15 days of treatment, MTD was more sensitive than ZN staining (12/43 [28%] versus 2/43 [2%]; P = 0.013). Slower bacterial clearance was observed if M. tuberculosis was resistant to isoniazid and/or streptomycin: resistant organisms were more likely to be cultured from cerebrospinal fluid after 2 to 5 days of treatment than fully sensitive organisms (P < 0.001). The sensitivities of ZN staining, MTD, and the two tests combined were improved by repeated sampling to 38/59 (64%), 35/59 (59%), and 49/59 (83%), respectively. In conclusion, ZN staining of the cerebrospinal fluid is at least as good as MTD for the rapid diagnosis of tuberculosis and is much faster and less expensive. However, the combination of these methods on serial samples detects more cases. Alternative tests are still urgently required. 相似文献
80.
The retention of nursing students is an ongoing problem, both within the United Kingdom (UK) and internationally. While there is a plethora of literature relating to student attrition, there is an absence of evidence in relation to the experiences of those students who are struggling to meet the demands of nursing programmes. Using an inductive sociological enquiry based approach, this study sought to examine the experiences of student nurses after referral on the first attempt of a summative assessment. Nursing students who had failed an assignment (n=20) were invited to participate. Data was collected using focus groups, with the emergent themes collapsed into a concise format using thematic content analysis. Four key themes were identified: desire to succeed; acceptance of personal failure; recognition of personal attributes required for success; and responsibility for personal success and failure. Students remained on the programme, despite struggling with financial and personal difficulties, because the desire to become a qualified nurse outweighed transient hardships. This paper will illustrate the benefits of understanding the students' experiences, in order to ensure the support students receive is appropriate to their needs. Understanding the support strategies as perceived by the students may prevent further wastage from nursing programmes. 相似文献