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To assess the effect of surfactant replacement therapy (SRT) on the prevalence and severity of retinopathy of prematurity (ROP), we compared data from 160 SRT-treated preterm infants with data from 230 historic controls. The prevalence of ROP was 30.6% in the treatment group and 23.4% in the control group. Severe ROP (stages 3-4) was seen in 6.1% of the infants with ROP in the treatment group and 20.3% of the ROP patients in the control group. Surfactant therapy had no influence on the prevalence of ROP (odds ratio 1.4, 95% confidence interval 0.797-2.459, p = 0.242). However, SRT was associated with a decreased risk for severe ROP, compared to mild ROP (odds ratio 0.226, 95% confidence interval 0.056-0.905, p = 0.036). These data suggest that SRT is associated with a decreased risk for severe ROP.  相似文献   
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Introduced more than 15 years ago, balloon aortic valvuloplasty (BAV) has clearly delineated indications and limitations. Although, aortic valve replacement is undoubtedly the treatment of choice for healthy patients with aortic stenosis, BAV has been demonstrated as a valuable and safe palliative procedure for patients considered too risky or old for current day surgery. Between January 1991 and December 1999, 858 patients (mean age 76 ± 11 years, 479 [57%] women) underwent BAV at our center. Indications for BAV were contraindication to surgery in 16.2% of the patients, high risk in 40.4%, refusal of surgery in 10.7%, personal decision in 18.5%, and other in 14.2%. The mean gradient decreased from 65 ± 23 to 27 ± 12 mmHg and the valve area increased from 0.56 ± 0.19 cm2 to 1.0 ± 0.38 cm2. Eleven (1.1%) patients died during the procedure. The other severe complications were complete AV block in 18 (1.8%) patients, stroke in 8 (0.8%), tamponade in 6 (0.6%), and massive aortic insufficiency in 4 (0.4%). In conclusion, BAV does not replace valve replacement, even in the elderly. All those who can be operated on, should be. However, if surgical intervention is not considered reasonable, BAV offers good immediate results with an acceptable complication rate. Furthermore, previous published series have demonstrated that BAV is particularly indicated in specific subgroups, such as very old patients with high operative risk, end-stage heart failure, cardiogenic shock, or general anesthesia for noncardiac surgery.  相似文献   
35.

Purpose

To assess local control, event‐free survival (EFS), and overall survival (OS) rates in 71 patients with localized, completely resected (Group I) alveolar rhabdomyosarcoma (ALV RMS) and their relation to radiation therapy (RT) on IRSG Protocols III and IV, 1984–1997.

Methods

Chart review and standard statistical procedures.

Patients and Tumors

Patients were 1–18 years at diagnosis (median, 6 years). Primary tumor sites were extremity/trunk (N = 54), head/neck (N = 9), genitourinary tract (N = 7), and perineum (N = 1). Thirty patients received VA ± C with RT; 41 received VA ± C alone. RT was assigned, not randomized.

Results

Fifty‐four patients had Stage 1 (favorable site, any size) or Stage 2 (unfavorable site, ≤5 cm) tumors. Eight‐year EFS was 90%, with 100% local control for 17 patients given RT. Eight‐year EFS was 88%, with 92% local control for 37 patients without RT; P = 0.52 for EFS comparisons, 0.3 for local control comparisons. In 17 Stage 3 patients (unfavorable site, tumors >5 cm, N0), 8‐year EFS was 84% with 100% local control in 13 patients given RT; 8‐year EFS was only 25% and local control 50% in 4 patients without RT. Local recurrence was the most common site of first failure in non‐irradiated patients.

Conclusion

Patients with Stage 1–2 ALV RMS had slightly but statistically insignificantly improved local control, EFS, and OS rates when local RT was given. The need for local RT in Stage 1–2 patients deserves evaluation in a randomized study. Local control, EFS, and OS rates were significantly improved in Stage 3 patients receiving local RT. Pediatr Blood Cancer. 2010;55:612–616. © 2010 Wiley‐Liss, Inc.  相似文献   
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37.
Volumetric rendering of MR images   总被引:1,自引:0,他引:1  
The authors developed new techniques for three-dimensional display of magnetic resonance (MR) images that preserve soft-tissue definition, are fully automatic, and work with routinely used section thicknesses. MR images are segmented, selectively enhanced, and displayed by means of a volumetric rendering algorithm. These techniques were used to illustrate normal anatomy of the brain, knee, and liver. Three-dimensional rendering of balanced spin-echo images shows the ventricles and extracerebral veins and of T1-weighted images, the sulci and gyri. The large hepatic and portal vessels can be seen with these enhancement techniques. Three-dimensional views of the knee reveal articular surfaces of the tibia and clearly depict menisci and posterior and anterior cruciate ligaments. These techniques make it possible to image multiple soft tissues simultaneously while preserving the detail contained in the original images. Three-dimensional presentation of complex, overlapping anatomic regions is helpful in surgical planning and should lead to improved diagnosis.  相似文献   
38.
A total of 97 women with good-risk metastatic breast cancer received therapy with cyclophosphamide, doxorubicin, and 5-FU; half of these patients were randomly allocated to receive levamisole, 2.5 mg/kg, 2 days of each week in addition to chemotherapy, while the other half received an identical placebo. Good-risk patients consisted of those with bone-only metastasis, or local chest wall recurrence with or without bone metastasis. No significant difference in response rate, duration of disease control, or survival was observed between the groups. No major toxicity was associated with levamisole.  相似文献   
39.
The objective of the study was to develop a clinical prediction rule (CPR) to identify patients with neck pain likely to improve with cervical traction. The study design included prospective cohort of patients with neck pain referred to physical therapy. Development of a CPR will assist clinicians in classifying patients with neck pain likely to benefit from cervical traction. Eighty patients with neck pain received a standardized examination and then completed six sessions of intermittent cervical traction and cervical strengthening exercises twice weekly for 3 weeks. Patient outcome was classified at the end of treatment, based on perceived recovery according to the global rating of change. Patients who achieved a change ≥+6 (“A great deal better” or “A very great deal better”) were classified as having a successful outcome. Univariate analyses (t tests and chi-square) were conducted on historical and physical examination items to determine potential predictors of successful outcome. Variables with a significance level of P ≤ 0.15 were retained as potential prediction variables. Sensitivity, specificity and positive and negative likelihood ratios (LRs) were then calculated for all variables with a significant relationship with the reference criterion of successful outcome. Potential predictor variables were entered into a step-wise logistic regression model to determine the most accurate set of clinical examination items for prediction of treatment success. Sixty-eight patients (38 female) were included in data analysis of which 30 had a successful outcome. A CPR with five variables was identified: (1) patient reported peripheralization with lower cervical spine (C4–7) mobility testing; (2) positive shoulder abduction test; (3) age ≥55; (4) positive upper limb tension test A; and (5) positive neck distraction test. Having at least three out of five predictors present resulted in a +LR equal to 4.81 (95% CI = 2.17–11.4), increasing the likelihood of success with cervical traction from 44 to 79.2%. If at least four out of five variables were present, the +LR was equal to 23.1 (2.5–227.9), increasing the post-test probability of having improvement with cervical traction to 94.8%. This preliminary CPR provides the ability to a priori identify patients with neck pain likely to experience a dramatic response with cervical traction and exercise. Before the rule can be implemented in routine clinical practice, future studies are necessary to validate the rule. The CPR developed in this study may improve clinical decision-making by assisting clinicians in identifying patients with neck pain likely to benefit from cervical traction and exercise. This study was approved by the Institutional Review Board at Brooke Army Medical Center, Fort Sam Houston, Texas. The opinions and assertions contained herein are the private views of the authors and are not to be construed as official as reflecting the views of the Department of the Army, Department of the Air Force, Department of the Navy, or the Department of Defense.  相似文献   
40.
Anesthesia in developing countries deserves special attention. The most common technique is general anesthesia (with spontaneous or manually assisted ventilation). Nonmedical anesthetists with limited training and supervision and lacking the most common drugs and anesthetic equipment administer anesthesia, usually for emergency surgery. There are important safety issues, especially for pediatric anesthesia. Regarding pediatric surgery, the major workload is due to abdominal emergencies, mainly neonatal bowel obstruction or peritonitis due to typhoid perforation. The morbidity and mortality rate for these conditions is high.  相似文献   
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