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排序方式: 共有2541条查询结果,搜索用时 15 毫秒
41.
Positron emission tomography in the clinical staging of patients with Stage I and II testicular germ cell tumors 总被引:3,自引:0,他引:3
OBJECTIVES: To evaluate the accuracy of fluorodeoxyglucose positron emission tomography (PET) compared with computed tomography (CT) staging in patients with Stage I and II testicular germ cell tumors (GCTs). METHODS: From January 1995 to July 1997, in 37 patients with clinical Stage (CS) I (n = 25) and CS II (n = 12) GCT (24 nonseminomas, 13 seminomas), PET and CT were compared in the initial staging. After PET, the patients with nonseminomatous GCT were staged surgically by retroperitoneal lymph node dissection and the patients with seminomatous GCT were followed up clinically. RESULTS: Correct staging by PET was achieved in 34 of 37 patients compared with correct CT staging in 29 of 37 patients. Of 10 metastatic lesions, 7 and 4 were detected by PET and CT, respectively. PET did not show false-positive signals. PET was unable to detect vital cancer with a maximal diameter less than 0.5 cm or teratoma at any size. CONCLUSIONS: PET was useful for detecting viable tumor in lesions that are visible on CT scan and, thus, it may omit false-positive CS II lesions. However, PET was not able to identify mature teratoma. In this study, PET did not improve the staging in patients with CS I tumor. 相似文献
42.
Choice of endpoints in antiplatelet trials: which outcomes are most relevant to stroke patients? 总被引:2,自引:0,他引:2
Albers GW 《Neurology》2000,54(5):1022-1028
The relative efficacies of different antiplatelet agents for stroke prevention are unclear because of differences in clinical trial design, a lack of direct comparisons between individual agents, and differences in the choice of primary endpoints. Individual endpoints in a clinical trial are often combined into a single primary endpoint cluster. Theoretically, a combined endpoint may reduce the sample size required to demonstrate significant benefits of an effective therapy. However, unless all components of a composite endpoint are affected in the same direction and to a similar degree, their inclusion may not provide the anticipated increase in statistical power. In fact, the use of a combined endpoint may lead to an underestimate of therapeutic benefits when patients at high risk for one particular endpoint are studied. For patients with stroke or TIA, the single outcome of stroke is particularly important because these patients have a higher risk of recurrent stroke than any other vascular outcome during the initial years after a stroke. Because of the low incidence of myocardial infarction (MI) in stroke trials, the inclusion of MI in the primary endpoint will usually have minimal influence on trial outcome, and antiplatelet therapy has not been shown to be beneficial in preventing nonvascular death. Chance variations in the incidence of MI or death may detract from the benefit of the agent for stroke prevention when it is included in a combined endpoint. The benefit of antiplatelet therapies for patients with recent cerebrovascular events is determined most accurately if stroke alone is chosen as the primary endpoint. 相似文献
43.
44.
Selfotel in acute ischemic stroke : possible neurotoxic effects of an NMDA antagonist 总被引:19,自引:0,他引:19
Davis SM Lees KR Albers GW Diener HC Markabi S Karlsson G Norris J 《Stroke; a journal of cerebral circulation》2000,31(2):347-354
BACKGROUND AND PURPOSE: Based on neuroprotective efficacy in animal models, we evaluated the N-methyl D-aspartate antagonist Selfotel in patients with ischemic stroke, after doses up to 1.5 mg/kg were shown to be safe in phase 1 and phase 2a studies. METHODS: Two pivotal phase 3 ischemic stroke trials tested the hypothesis, by double-blind, randomized, placebo-controlled parallel design, that a single intravenous 1.5 mg/kg dose of Selfotel, administered within 6 hours of stroke onset, would improve functional outcome at 90 days, defined as the proportion of patients achieving a Barthel Index score of >/=60. The trials were performed in patients aged 40 to 85 years with acute ischemic hemispheric stroke and a motor deficit. RESULTS: The 2 trials were suspended on advice of the independent Data Safety Monitoring Board because of an imbalance in mortality after a total enrollment of 567 patients. The groups were well matched for initial stroke severity and time from stroke onset to therapy. There was no difference in the 90-day mortality rate, with 62 deaths (22%) in the Selfotel group and 49 (17%) in the placebo-treated group (RR=1.3; 95% CI 0.92 to 1.83; P=0.15). However, early mortality was higher in the Selfotel-treated patients (day 30: 54 of 280 versus 37 of 286; P=0.05). In patients with severe stroke, mortality imbalance was significant throughout the trial (P=0.05). CONCLUSIONS: Selfotel was not an effective treatment for acute ischemic stroke. Furthermore, a trend toward increased mortality, particularly within the first 30 days and in patients with severe stroke, suggests that the drug might have a neurotoxic effect in brain ischemia. 相似文献
45.
46.
Predictors of occult metastasis in clinical stage I nonseminoma: a systematic review. 总被引:3,自引:0,他引:3
Yvonne Vergouwe Ewout W Steyerberg Marinus J C Eijkemans Peter Albers J Dik F Habbema 《Journal of clinical oncology》2003,21(22):4092-4099
PURPOSE: Patients with clinical stage I nonseminomatous testicular germ cell tumor should ideally receive adjuvant therapy only when they are at high risk for occult metastasis. We aimed to quantify the importance of predictors for occult metastasis by performing a systematic review of the relevant literature. In addition, we reviewed published multivariable models and risk-adapted treatment policies. PATIENTS AND METHODS: We identified 23 publications between 1979 and 2001, reporting a total of 2,587 patients. Twenty-nine percent of the patients (759 of 2,587 patients) had occult metastases, which was diagnosed either at retroperitoneal lymph node dissection (n = 193) or during follow-up (n = 566). Odds ratios (OR) were pooled using meta-analysis techniques. RESULTS: The presence of vascular invasion of the primary tumor cells had the strongest effect (OR, 5.2; 95% CI, 4.0 to 6.8). Immunohistochemical staining of the primary tumor cells with the MIB-1 monoclonal antibody showing proliferative activity was a promising predictor (OR, 4.7; 95% CI, 2.0 to 11). Intermediate effects were found for embryonal carcinoma in the primary tumor (OR, 2.9; 95% CI, 2.0 to 4.4) and a high pathologic stage of the tumor (OR, 2.6; 95% CI, 1.8 to 3.8). Size of the primary tumor and age of the patient had weaker though also statistically significant associations with occult metastasis. Until now, multivariable models often included vascular invasion and embryonal carcinoma with one or two weaker predictors. None of the published risk-adapted treatment policies included MIB-1 staining. CONCLUSION: Several strong predictors for occult metastasis were identified. A risk-adapted treatment policy should be developed that incorporates all relevant predictors so that adjuvant therapy is targeted better to those with occult metastases. 相似文献
47.
Peter Albers Roswitha Siener Sabine Kliesch Lothar Weissbach Susanne Krege Christoph Sparwasser Harald Schulze Axel Heidenreich Werner de Riese Volker Loy Erhard Bierhoff Christian Wittekind Rolf Fimmers Michael Hartmann 《Journal of clinical oncology》2003,21(8):1505-1512
PURPOSE: To prospectively assess potential risk factors for relapse in clinical stage I nonseminomatous germ cell tumors of the testis (CS I NSGCT). PATIENTS AND METHODS: From September 1996 to May 2002, 200 patients with CS I NSGCT were prospectively assigned to retroperitoneal lymph node dissection (RPLND), and risk factor assessment was performed within a multicenter protocol. One hundred sixty-five patients had an adequate minimum follow-up of 12 months (mean, 34.5 months) or had pathologic stage II. RESULTS: Pathologic stage II disease was found in 27.9% of patients. Only 0.6% of patients relapsed in the retroperitoneum after confirmation of pathologic stage I disease. With reference pathology, vascular invasion (VI) was most predictive of stage in multifactorial analysis (accuracy, 65.1%). However, the positive predictive value (PPV) of VI to predict patients who have metastatic disease or relapse during follow-up was only 52.7%. With absent VI, low-risk patients had a negative predictive value (NPV) of 76.9%. With a combination of several risk factors, the PPV increased to 63.6% and the negative predictive value increased to 86.5%. CONCLUSION: Even with an optimal combination of prognostic factors and reference pathology, more than one third of patients predicted to have pathologic stage II or relapse during follow-up will not harbor metastatic disease and, therefore, would be overtreated with adjuvant therapy. However, patients at low risk may be predicted at an 86.5% level, and thus, surveillance in highly compliant patients would be a valuable option. For high-risk patients, further reduction of adjuvant treatment is necessary. 相似文献
48.
49.
Leah L. Albers Deborah Anderson Leslie Cragin Susan Moore Daniels Christine Hunter Kay D. Sedler Dusty Teaf 《Journal of Midwifery & Women's Health》1997,42(1):4-8
An abbreviated version of the Nurse-Midwifery Clinical Data Set was used to gather data on all women (n = 3,049) who began intrapartum care with a nurse-midwife in three sites. Demographic information, intrapartum care, and outcomes were recorded. The association of ambulation in labor with operative delivery was examined in a low-risk sample (n = 1,678) of women who did not receive care measures (epidural anesthesia, oxytocin induction or augmentation) that preclude mobility in labor. Women who ambulated for a significant amount of time during labor (compared with those who did not ambulate) had half the rate of operative delivery (2.7% vs. 5.5%). 相似文献
50.
Epidural analgesia is widely available and increasingly popular in the United States for pain relief in childbirth. Although it provides superior pain relief for most women, it is not without significant short- and long-term side effects. It is costly and requires the use of numerous other technologic interventions. Because women have information needs surrounding childbirth and value self-determination, full informed consent regarding epidural analgesia should be a priority in patient care. The best time and place in which to accomplish this is during the prenatal period. 相似文献