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排序方式: 共有3445条查询结果,搜索用时 15 毫秒
41.
Purpose: Randomised controlled trials (RCTs) guide therapeutic decisions. But which RCTs are done; which omitted; and which should be done? This study illustrates a method to explore these questions applied to drugs for post-operative nausea and vomiting (PONV). Methods: Review artides listed 18 drugs for PONV. All RCTs of these drugs for PONV were sought. The first drug mentioned in an RCT was counted and tabulated against others in all the arms of the RCT (against itself in a dose-ranging RCT). Additional drugs mentioned in these RCTs were added to the study, for a total of 40 drugs. Results: Drugs involved in the most RCTs were: ondansetron 131 RCTs; propofol 118; droperidol 74; metoclopramide 67; granisetron 52; scopolamine 22; tropisetron 16. Drugs involved in the fewest RCTs: two drugs with 2 RCTs; twelve drugs with one; three with none. Probability that this distribution occurred by chance:P<0.00001; that the distribution of dose-ranging RCTs occurred by chance:P<0.001. Regression of RCT numbers on cost: R=0.86,P<0.0001; on year of drug introduction: R=0.14. Of 1600 possible comparisons of drugs for PONV, (including dose-ranging) 97.8% have never been published. Conclusion: Although some antiemetic drugs for PONV have been studied in large numbers of RCTs, many have not been adequately evaluated. Finding relevant RCTs and tabulating their comparison arms is useful for directing future research, and is applicable to any symptom or disorder. 相似文献
42.
A 39-year-old man presented with intermittent painless macroscopic haematuria. He was subsequently diagnosed to have a high grade leiomyosarcoma of the bladder. He underwent total cystoprostatectomy and radiotherapy but died of metastatic disease five months after the initial diagnosis. Aspects of the imaging and diagnostic pathway of painless haematuria are discussed. The management of leiomyosarcomas in the urinary system is highlighted. 相似文献
43.
Acquired cystic disease of the kidney and renal cell carcinoma are associated with chronic renal failure. In recent years, there has been increased incidental detection of renal tumours through the liberal use of ultrasonography (US) and computed tomography (CT). A 40-year-old man suffering from chronic renal failure and who was being treated with haemodialysis for six years, was found to have a complex cystic lesion on US and CT. Nephrectomy was performed and the lesion was confirmed to be renal cell carcinoma associated with acquired cystic kidney disease. The current role of imaging in the management of affected patients are discussed. 相似文献
44.
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
45.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
46.
Ambulatory labor epidural analgesia: bupivacaine versus ropivacaine 总被引:11,自引:0,他引:11
Dilute concentrations of bupivacaine combined with fentanyl have recently been used to initiate labor epidural analgesia in an attempt to balance adequate analgesia and minimal maternal motor blockade. Similar concentrations of ropivacaine have not been evaluated. This prospective, randomized, double-blinded study was designed to compare the efficacy of 20 mL of either 0.08% bupivacaine plus 2 microg/mL fentanyl or 0.08% ropivacaine plus 2 microg/mL fentanyl to initiate ambulatory labor epidural analgesia. Forty nulliparous women in early (=5 cm) established labor received either 20 mL of 0.08% bupivacaine plus 2 microg/mL fentanyl (BF) or 0.08% ropivacaine plus 2 microg/mL fentanyl (RF) to initiate epidural analgesia. One woman (BF) required supplemental analgesia, and two (one BF and one RF) had visual analog scale scores > 0 but < 20 at 20 min. The time (mean +/- SD) to visual analog scale score = 0 was BF (n = 18): 12.0 +/- 4.5 min and RF (n = 19): 12.4 +/- 4.0 min (P > 0.05). Spontaneous micturition was observed in 65% (13 of 20) BF compared with 100% (20 of 20) RF (P < 0.01), and ambulation was demonstrated in 75% (15 of 20) BF compared with 100% (20 of 20) RF (P < 0.03). The incidence of forceps delivery was 35% (7 of 20) BF compared with 10% (2 of 20) RF (P < 0.04). The results of this study indicate that dilute ropivacaine combined with fentanyl effectively initiates epidural analgesia while concurrently preserving maternal ability to void and ambulate. Implications: As compared with a similar dilute concentration of bupivacaine, 20 mL of dilute (0.08%) ropivacaine combined with fentanyl (2 microg/mL) effectively initiates epidural analgesia in nulliparous women in early, established labor while preserving their ability to micturate and ambulate. Of importance, it appears that a true ambulatory epidural analgesic for women in labor is now possible. 相似文献
47.
Kenneth W Yip Joseph D Mocanu P Y Billie Au Gillian T Sleep Dolly Huang Pierre Busson Wen-Chen Yeh Ralph Gilbert Brian O'Sullivan Patrick Gullane Carlo Bastianutto Fei-Fei Liu 《Clinical cancer research》2005,11(22):8131-8144
PURPOSE: A wide variety of tumors depend on the dysregulation of Bcl-2 family proteins for survival. The resulting apoptotic block can often provide a mechanism for resistance to anticancer treatments, such as chemotherapy and radiation. This current study evaluates the efficacy of combining systemically delivered Bcl-2 phosphorothioate antisense (Bcl-2 ASO) and radiation for nasopharyngeal cancer therapy. RESULTS: Antisense uptake was unaffected by 0, 3, or 6 Gy radiation. Radiation decreased the fraction of viable C666-1 cells to 60%, with a further decrease to 40% in combination with Bcl-2 ASO. Despite a modest in vitro effect, Bcl-2 ASO alone caused the regression of established xenograft tumors in mice, extending survival by 15 days in a C666-1 and by 6 days in a C15 model. The survival times for mice treated with both Bcl-2 ASO and radiation increased by 52 days in C666-1 and by 20 days in C15 tumors. This combination resulted in a more-than-additive effect in C666-1 tumors. Less impressive gains observed in C15 tumors might be attributable to higher expression of antiapoptotic Bcl-2 family proteins and limited drug distribution in the tumor. Retreatment of C666-1 tumors with the Bcl-2 ASO-radiation combination, however, was effective, resulting in mice surviving for >80 days relative to untreated controls. CONCLUSIONS: Our results show that the Bcl-2 ASO and radiation combination is a highly potent therapy for nasopharyngeal cancer. Further examination of combination therapy with radiation and other Bcl-2 family-targeted anticancer agents in both preclinical and clinical settings is definitely warranted. 相似文献
48.
目的 评估VERIS mfERG (EDI Inc)和Espion multifocal imager (Diagnosys)两种不同系统测量正常眼多焦视网膜电图(mfERG)的电位波反应的差异及其相关性,并用两个不同系统分别测量黄斑前膜患眼的mfERG并进行分析.方法 这是一项横断面研究,在VERIS系统使用Burian-Allen (BA)电极,Espion系统使用BA和DTL电极分别测量25只正常眼的mfERG,将3次测得的一阶反应的相应数据进行配对t检验及Pearson相关分析.两个系统用BA电极分别测量19只黄斑前膜患眼的mfERG,对一阶反应的相应数据进行Fisher's exact test分析.结果 VERIS BA测得正常眼N1波、P1波振幅密度值最大,其次为Espion BA,Espion DTL最小;VERIS BA测得N1波、P1波潜伏期最长,Espion BA与Espion DTL差异无统计学意义.Espion BA与VERIS BA测得的P1波振幅密度、潜伏期皆有明显的相关性.黄斑前膜患眼中,VERIS BA比Espion BA能检测到更多P1波振幅密度和P1波潜伏期的异常.结论 不论VERIS或Espion系统都能成功记录多焦视网膜电图,当两种系统都使用Burian-Allen电极时,两者mfERG一阶反应P1波振幅密度及潜伏期有着良好的相关性. 相似文献
49.
Singapore Indian Eye Study‐2: methodology and impact of migration on systemic and eye outcomes 下载免费PDF全文
50.
Altitude and childhood growth 总被引:2,自引:0,他引:2
To assess the possible influence of altitude on childhood growth in the United States, we used data collected by the Centers for Disease Control Pediatric Nutrition. Surveillance System from eight mountain states to determine the height and weight status of children aged 5 years or younger enrolled in various public health programs between 1982 and 1984. The mean birth weight, height-for-age, weight-for-age, and weight-for-height indicators were found to decline significantly with increasing altitude, starting at an elevation greater than 1500 m (p less than 0.001, ANOVA). The reduction in growth was observed for all age groups and all birth weight groups studied. Part of the observed reduction in growth could be attributed to the lower birth weight of children born at higher altitude. However, the reduced growth status persisted after controlling for birth weight, suggesting the presence of an extrauterine growth retardation effect related to altitude. 相似文献