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91.
92.
Ung YC Maziak DE Vanderveen JA Smith CA Gulenchyn K Lacchetti C Evans WK;Lung Cancer Disease Site Group of Cancer Care Ontario's Program in Evidence-Based Care 《Journal of the National Cancer Institute》2007,99(23):1753-1767
Lung cancer is the leading cause of cancer-related death in industrialized countries. The overall mortality rate for lung cancer is high, and early diagnosis provides the best chance for survival. Diagnostic tests guide lung cancer management decisions, and clinicians increasingly use diagnostic imaging in an effort to improve the management of patients with lung cancer. This systematic review, an expansion of a health technology assessment conducted in 2001 by the Institute for Clinical and Evaluative Sciences, evaluates the accuracy and utility of 18fluorodeoxyglucose positron emission tomography (PET) in the diagnosis and staging of lung cancer. Through a systematic search of the literature, we identified relevant health technology assessments, randomized trials, and meta-analyses published since the earlier review, including 12 evidence summary reports and 15 prospective studies of the diagnostic accuracy of PET. PET appears to have high sensitivity and reasonable specificity for differentiating benign from malignant lesions as small as 1 cm. PET appears superior to computed tomography imaging for mediastinal staging in non-small cell lung cancer (NSCLC). Randomized trials evaluating the utility of PET in potentially resectable NSCLC report conflicting results in terms of the relative reduction in the number of noncurative thoracotomies. PET has not been studied as extensively in patients with small-cell lung cancer, but the available data show that it has good accuracy in staging extensive- versus limited-stage disease. Although the current evidence is conflicting, PET may improve results of early-stage lung cancer by identifying patients who have evidence of metastatic disease that is beyond the scope of surgical resection and that is not evident by standard preoperative staging procedures. Further trials are necessary to establish the clinical utility of PET as part of the standard preoperative assessment of early-stage lung cancer. 相似文献
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Kim Ann Ung Maria Portillo Brigid Moran Tomas Kron Brooke Sawyer Alan Herschtal Boon H. Chua 《Practical radiation oncology》2013,3(4):e131-e137
PurposeThe thyroid is not routinely considered an organ at risk in supraclavicular (SC) nodal radiation therapy (RT) for breast cancer. We compared the dosimetric impact of the following 2 RT planning techniques on the thyroid: (1) conventional single anterior field to encompass the SC nodal volume defined clinically; and (2) 3-dimensional conformal radiation therapy (3DCRT) planning to encompass the computed tomography (CT)-contoured SC nodal volume.Methods and MaterialsThe thyroid, SC nodal volumes, and organs at risk were contoured on the planning CT of 20 patients who received 50 Gy in 2-Gy daily fractions to the breast or chest wall, and SC nodes. Comparisons of dosimetric parameters between the techniques were performed: thyroid, mean and maximum dose, V5, V30, and V50 (percentage of thyroid receiving ≥ 5 Gy, ≥ 30 Gy, and ≥ 50 Gy, respectively); SC nodal volume, homogeneity index (HI, percentage volume receiving 95%-107% of prescribed dose); and maximum doses of spinal cord and brachial plexus. Anatomic characteristics that influenced the dose distributions were investigated.ResultsThe 3DCRT planning technique significantly increased all thyroid dosimetric measures (mean dose 17.2 Gy vs 26.7 Gy; maximum dose 48.5 Gy vs 51.9 Gy; V5 45.7% vs 64.9%; V30 33.7% vs 48%; and V50 0.6% vs 26.7%; P < .001). It improved HI for the SC nodal volumes (P < .001) but resulted in higher maximum doses to the spinal cord (6.1 Gy vs 30 Gy) and brachial plexus (43.2 Gy vs 51.4 Gy). The thyroid volume and depth of SC nodes did not influence the thyroid dose distribution. The depth of SC nodes impacted on the HI of SC nodal volumes in the conventional technique (P = .004).ConclusionsThe 3DCRT planning improved dosimetric coverage of the SC nodal volume but increased thyroid radiation doses. The potential adverse effects of incidental thyroid irradiation should be considered while improving dosimetric coverage in SC nodal irradiation for breast cancer. 相似文献
95.
神经外科中高渗盐注射液应用研究进展 总被引:1,自引:0,他引:1
控制脑水肿和颅内压(ICP)升高是神经外科围手术期治疗的重要组成部分.颅脑创伤、动脉梗塞、静脉高压/梗塞、大脑内出血、蛛网膜下腔出血、肿瘤和术后脑组织水肿的治疗过程中ICP的控制都是决定患者预后的关键因素.虽然利用渗透压脱水药物是控制ICP的最基础的工具,但却缺乏前瞻性研究以指导其运用,高渗盐被认为是甘露醇的替代物,早期的数据表明每种药的用药指征最终取决于ICP的病因.在这篇综述中,我们总结了有关高渗盐(HS)治疗颅内高压的相关数据,以及这些数据和我们有关HS的经验是如何指导目前的ICP治疗的. 相似文献
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Davies M Lavalle-González F Storms F Gomis R;AT.LANTUS Study Group 《Diabetes, obesity & metabolism》2008,10(5):387-399
Objective: For many patients with type 2 diabetes, oral antidiabetic agents (OADs) do not provide optimal glycaemic control, necessitating insulin therapy. Fear of hypoglycaemia is a major barrier to initiating insulin therapy. The AT.LANTUS study investigated optimal methods to initiate and maintain insulin glargine (LANTUS®, glargine, Sanofi-aventis, Paris, France) therapy using two treatment algorithms. This subgroup analysis investigated the initiation of once-daily glargine therapy in patients suboptimally controlled on multiple OADs. Research Design and Methods: This study was a 24-week, multinational (59 countries), multicenter (611), randomized study. Algorithm 1 was a clinic-driven titration and algorithm 2 was a patient-driven titration. Titration was based on target fasting blood glucose ≤100 mg/dl (≤5.5 mmol/l). Algorithms were compared for incidence of severe hypoglycaemia [requiring assistance and blood glucose <50 mg/dl (<2.8 mmol/l)] and baseline to end-point change in haemoglobin A1c (HbA1c). Results: Of the 4961 patients enrolled in the study, 865 were included in this subgroup analysis: 340 received glargine plus 1 OAD and 525 received glargine plus >1 OAD. Incidence of severe hypoglycaemia was <1%. HbA1c decreased significantly between baseline and end-point for patients receiving glargine plus 1 OAD (−1.4%, p < 0.001; algorithm 1 −1.3% vs. algorithm 2 −1.5%; p = 0.03) and glargine plus >1 OAD (−1.7%, p < 0.001; algorithm 1 −1.5% vs. algorithm 2 −1.8%; p = 0.001). Conclusions: This study shows that initiation of once-daily glargine with OADs results in significant reduction of HbA1c with a low risk of hypoglycaemia. The greater reduction in HbA1c was seen in patients randomized to the patient-driven algorithm (algorithm 2) on 1 or >1 OAD. 相似文献
99.
Bajor A Kilander A Sjövall H Rudling M Ung KA 《Digestive diseases and sciences》2008,53(11):2935-2940
The stability of bile acid turnover rate was evaluated retrospectively using repeat SeHCAT tests in patients with chronic
diarrhoea and prospectively for 16 years in healthy subjects. The SeHCAT values were stable in 39 patients with chronic diarrhoea,
as shown by a comparison of the test results [data presented as median and (25th–75th percentile)]: 18% (8–23) in the first
test versus 14% (9–21) in the second test [n = 39, P = 0.37, time interval 44 months (16–68), repeatability index >95%]. In contrast, they were reduced after 16 years in healthy
subjects: 38% (30–49.5) in the first test versus 31% (21–49.5) in the second test (P < 0.03). In healthy subjects, the body mass index increased by 13% from 23.2 kg/m2 (21–24.6) to 26.2 kg/m2 (22.5–27.8) (P < 0.01) during the 16 years. There was a negative correlation between hepatic bile acid synthesis and the SeHCAT values (r = −0.615, P = 0.02, n = 14). In conclusion, the turnover rate of bile acids is stable over a long period of time in patients with chronic diarrhoea
irrespective of bile acid malabsorption, suggesting that a repeat SeHCAT test is dispensable. There is a significant negative
correlation between bile acid synthesis and SeHCAT test results in healthy subjects. The SeHCAT test values are slightly reduced
in healthy subjects after 16 years. 相似文献
100.
Lee JU Shin J Song W Kim H Lee S Jang SJ Wong SC Edelberg JE Liau G Hong MK 《Coronary artery disease》2005,16(7):451-456
OBJECTIVES: We previously demonstrated that sphingosine kinase (SPK) increases the level of extracellular sphingosine-1-phosphate and promotes neovascularization in a mouse matrigel model. In this study, we tested the hypothesis that SPK gene transfer using a novel adenoviral 'gutless' vector (AGV) can enhance arteriogenesis in a rabbit hindlimb ischemia model. METHODS: Thirty-five male New Zealand white rabbits were randomized to the AGV-SPK group (n=13), AGV-null group (n=13), and control group (n=9). On day 10, after the induction of unilateral hindlimb ischemia, gene vectors or buffer were introduced and the effect examined on day 30, using calf blood pressure, quantitative angiographic analysis, and histology. RESULTS: Calf systolic blood pressure ratios of the ischemic limb to the normal limb on day 30 were 0.77+/-0.13 in control groups, including the AGV-null group, and 0.91+/-0.14 in the AGV-SPK group (P<0.05). Angiographic vessel counts were significantly increased (8.0+/-2.1 at baseline and 11.8+/-3.2 on day 30, P<0.001) in the AGV-SPK group. Histologic analysis showed that microscopic total vessel counts on day 30 were 3.5+/-1.8/field in the control and AGV-null group and 5.4+/-1.0/field in the AGV-SPK group. Arterioles (AGV-SPK; 3.0+/-0.8 versus control and AGV-null; 2.1+/-1.1, P<0.05) were significantly increased in the AGV-SPK group. CONCLUSIONS: This study shows that SPK promotes arteriogenesis, as evidenced by the maximal improvement in the blood pressure restoration and collateral vessel counts. SPK may be an important angiogenic target to improve perfusion in ischemic tissues. 相似文献