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61.
T W Shields G A Higgins M J Matthews R J Keehn 《The Journal of thoracic and cardiovascular surgery》1982,84(4):481-488
In an attempt to define the role of initial surgical resection in patients with undifferentiated small cell carcinoma of the lung, we reviewed the experience of the Veterans Administration Surgical Oncology Group (VASOG). One hundred forty-eight patients with small cell carcinoma of the lung had undergone a potentially "curative" resection. This represented 4.7% of "curative" resections carried out in four major prospective adjuvant chemotherapy trials. In the early trials (101 patients), 16 patients (15.8%) died within the first 30 postoperative days. These patients have been excluded from the analysis of long-term survival, since in the more recent trials postoperative deaths were excluded prior to randomization. In the 132 patients remaining, the 5 year survival rate by the life-table method was 23.0%. The tumor of each was classified pathologically by the TNM system. Five-year survival rates for each category were as follows: T1 N0 M0 59.9%, T1 N1 M0 31.3%, T2 N0 M0 27.9%, T2 N1 M0 9.0%, and any T3 or N2 3.6%. The effect of postoperative adjuvant chemotherapy was evaluated in each of the trials. No beneficial effect of the adjuvant therapy was noted with a one or two course regimen of either nitrogen mustard or cyclophosphamide, but possible benefit, although not significant, was noted in a prolonged intermittent chemotherapy trial of cyclophosphamide either alone or alternating with methotrexate. In the most recent trial of prolonged intermittent courses of 1-(2-chlorethyl)-3-cyclohexyl-l-nitrosourea (CCNU) and hydroxyurea, a 5 year survival rate of 80.8% was noted in those receiving adjuvant chemotherapy as compared to a 38.1% in the control group. We conclude that resection is definitely indicated in patients with T1 N0 M0 lesions and probably indicated in those with T1 N1 M0 or T2 N0 M0 lesions. Primary surgical resection is contraindicated in patients with any other TNM category. 相似文献
62.
Quality measurement and control in physician decision making: state of the art. 总被引:1,自引:1,他引:0 下载免费PDF全文
The status of the concept of controlling the quality of physicians is reviewed as are studies that have been done on methods to measure and improve quality. The conclusions are dismal given the rhetoric and actions on attempts to measure and control quality of physician decision making. Massive attempts are being made, for example, mandating PSROs to monitor quality before there is a methodology. Cost and quality reviews have, at most, a marginal impact and do not deserve the expenditures to conduct them. Studies on utilization review show minimal impact on reducing utilization. Administrative reviews reduce utilization for certain specific, narrowly defined procedures such as injections. There is no operational definition of "unnecessary" utilization. The tendency is to regard the lowest levels as optimal, presumably because they result in lower expenditures. Bureaucratic reviews do not provide incentives to decision makers the way various types of HMO delivery types do from current evidence. Hence, HMOs, deductibles and coinsurance, and competition have greater promise for limiting expenditures than do utilization reviews. Quality audits are also marginally effective because of limited promise of changing provider behavior given current methods of doing so. They miss the organizational aspects in which incentives are generated. Research is needed, therefore, on alternative forms of quality and cost control such as HMOs, physician risk sharing, competitive models, and deductibles and coinsurance. Until the much needed research has been done, the amount of resources spent on review should be minimized. In the meantime, the review processes should concentrate on extreme variations of very narrowly defined criteria of proven validity while improving the review methodology by systematic research on quality monitoring. 相似文献
63.
高效液相色谱法测定绿茶和饮料中的咖啡因 总被引:5,自引:0,他引:5
采用反相高效液相色谱法,固定相为十八烷基硅烷键合硅胶,以乙腈-水(20:80)为流动相,检测波长274nm,测定绿茶和饮料中的咖啡因含量。结果线性范围为3.9~3900ng,r=O.9999;绿茶和2种饮料的平均加样回收率分别为100.2%、100.1%和99.8%。该方法准确、简便、快速,适合绿茶和可乐型饮料中咖啡因的测定。 相似文献
64.
B F El-Rayes A Shields M Zalupski L K Heilbrun V Jain D Terry A Ferris P A Philip 《Annals of oncology》2004,15(6):960-965
BACKGROUND: This study was conducted to evaluate the efficacy and toxicity of combination carboplatin and paclitaxel in patients with esophageal cancer. MATERIALS AND METHODS: Thirty-five patients were enrolled. Patients were treated with paclitaxel 200 mg/m(2) intravenously (i.v.) over 3 h and carboplatin i.v. at an AUC of 5 mg/h/ml. Thirty-three patients were assessable for toxicity and objective response. RESULTS: A total of 166 treatment courses were administered with a median of five courses per patient. The objective response rate was 43% [90% confidence interval (CI) 0.3-0.58] by the intention-to-treat analysis. The median response duration was 2.8 months (90% CI 2.1-5.4). The median survival time was 9 months (90% CI 7-13.8) and the 1-year survival rate was 43% (90% CI 0.29-0.57). The major grade 3-4 toxicity observed was neutropenia, occurring in 17 patients (52%). There were no treatment-related deaths. CONCLUSIONS: The combination of carboplatin and paclitaxel is an moderately active and tolerable regimen in advanced esophageal cancer. 相似文献
65.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph. 相似文献
66.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
67.
OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants. 相似文献
68.
Satisfaction with midwife-managed care in different time periods: a randomised controlled trial of 1299 women. 总被引:1,自引:0,他引:1
OBJECTIVE: To compare women's satisfaction with midwife-managed care with 'shared care' over three different time periods. DESIGN: Randomised controlled trial. SETTING: Glasgow Royal Maternity Hospital, Glasgow, UK. PARTICIPANTS: 1299 women experiencing normal pregnancy (consent rate: 82%). Six hundred and forty-eight women were randomised to midwife-managed care and 651 to 'shared care'. METHODS: Three self-report questionnaires were sent to women's homes. The questionnaires examined: satisfaction with antenatal care at 34-35 weeks' gestation, and satisfaction with intrapartum, hospital- and home-based postnatal care at seven weeks postnatally. The third questionnaire reviewed satisfaction with intrapartum care seven months after delivery. FINDINGS: Women in both groups were satisfied. However, women in the midwife-managed group were more highly satisfied in relation to the dimensions examined: relationships with staff, information transfer, choices and decisions, and social support. The differences between the two groups were evident for all time periods (i.e. antenatal, intrapartum and postnatal periods) and were sustained at seven-month follow-up. This is illustrated in the mean scores for relationships with staff, as measured at 34-35 weeks' gestation (possible range -2; very negative attitudes to 2; very positive attitudes). Women in the midwife-managed group scored a mean of 1.22 compared to 0.74 for the 'shared care' group (mean diff: 0.48; 95% CI: 0.42 to 0.55). While women in both groups were more likely to make positive rather than negative comments in open-ended questions, the midwife-managed group were more likely to make positive comments whereas the 'shared care' group were more likely to make negative comments. CONCLUSION: Midwife-managed care for healthy pregnant women which is integrated into existing services improves satisfaction with antenatal, intrapartum and postnatal care. 相似文献
69.
外源核苷酸对免疫抑制小鼠胸腺细胞DNA损伤的影响 总被引:5,自引:0,他引:5
目的:检测外源核苷酸对经环磷酰胺诱导的免疫抑制小鼠胸腺细胞DNA损伤的影响。方法:采用18~20 g昆明种小鼠30只,雌雄各半,随机分成阴性对照组(NEC)、阳性对照组(POC)和核苷酸组(NTG),每组10只。NEC组和POC组小鼠均饲喂半纯合无核苷酸的基础日粮,NTG组则在基础日粮中添加0.25%的核苷酸,实验期为21 d。在实验结束前18 h POC组和NTG组小鼠按照150mg/kg bw的剂量腹腔注射环磷酰胺,NEC组注射生理盐水,实验结束时测定脾脏和胸腺脏器指数,并取胸腺细胞,做单细胞凝胶电泳,观察细胞DNA损伤情况。结果:在基础日粮中添加核苷酸对小鼠免疫器官重量没有显著影响(P>0.05),但能极显著降低受损胸腺细胞百分率(P<0.01)和受损细胞DNA尾长(P<0.01)。结论:外源核苷酸能显著降低免疫抑制小鼠受损胸腺细胞百分率和损伤程度。 相似文献
70.
目的探讨自我效能感与晕船症状的相关,以期寻找影响晕船的心理因素.方法对某院校参加海上实习的123名医疗本科学员用一般自我效能感量表、晕船自我效能感量表于出海作业前进行施测,用晕船症状评分量表于出海作业返回后进行评估.结果晕船自我效能感与晕船症状显著负相关(r=-0.470,P<0.01),而一般自我效能感量表与晕船症状的相关无统计学意义(r=-0.102,P>0.05).结论晕船自我效能感可能为个体发生晕船的心理影响因素之一. 相似文献