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81.
Mechanical ventilation in preterm infants: neurosonographic and developmental studies. 总被引:5,自引:0,他引:5
L J Graziani A R Spitzer D G Mitchell D A Merton C Stanley N Robinson L McKee 《Pediatrics》1992,90(4):515-522
Surviving preterm infants of less than 34 weeks' gestation who were selected on the basis of serial cranial ultrasonographic findings during their nursery course had repeated neurologic and developmental examinations during late infancy and early childhood that established the presence (n = 46) or absence (n = 205) of spastic forms of cerebral palsy. Of the 205 infants without cerebral palsy, 22 scored abnormally low on standardized developmental testing during early childhood. The need for mechanical ventilation beginning on the first day of life (n = 92) was significantly related to gestational age, birth weight, Apgar scores, patent ductus arteriosus, grade III/IV intracranial hemorrhage, large periventricular cysts, and the development of cerebral palsy. In the 192 mechanically ventilated infants, vaginal bleeding during the third trimester, low Apgar scores, and maximally low PCO2 values during the first 3 days of life were significantly related to large periventricular cysts (n = 41) and cerebral palsy (n = 43), but not to developmental delay in the absence of cerebral palsy (n = 18). The severity of intracranial hemorrhage in mechanically ventilated infants was significantly associated with gestational age and maximally low measurements of PCO2 and pH, but not with Apgar scores or maximally low measurements of PO2. Logistic regression analyses controlling for possible confounding variables disclosed that PCO2 values of less than 17 mm Hg during the first 3 days of life in mechanically ventilated infants were associated with a significantly increased risk of moderate to severe periventricular echodensity, large periventricular cysts, grade III/IV intracranial hemorrhage, and cerebral palsy. Neurosonographic abnormalities were highly predictive of cerebral palsy independent of PCO2 measurements.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
82.
83.
Dental schools are challenged to develop new learning methodologies and experiences to better prepare future dental practitioners. The purpose of this study was to gain insight into the community-based experiences of dental students as documented in their critical incident essays and explore what learning outcomes and benefits students reported. Following two required community-based clinical rotations, each student wrote a reflection essay on a self-defined critical incident that occurred during the rotations. Rotations took place in settings such as a public health clinic, special needs facility, hospital, or correctional institution. Essays for two classes of students were content-analyzed for recurring themes and categories. Students were confronted in their rotations with a wide range of situations not typically encountered in dental academic settings. Their essays showed that, as a result of these rotations, students developed increased self-awareness, empathy, communications skills, and self-confidence. Critical incidents challenged assumptions and stereotypes, enhanced awareness of the complexities of dental care, and raised complex ethical dilemmas. The essays also illustrated a heightened sense of professional identity and enabled students to appreciate the role dentistry can play in impacting patients' lives. We concluded from the study that community-based dental education that includes a process for reflection holds promise as an educational strategy to facilitate the personal and professional development of future dentists. 相似文献
84.
Strauss R Mofidi M Sandler ES Williamson R McMurtry BA Carl LS Neal EM 《Journal of dental education》2003,67(11):1234-1242
Learners gain additional value from community-based education when they are guided through a reflective process. The purpose of this article is to describe how structured reflection assignments and methods are incorporated in the University of North Carolina School of Dentistry's community-based DISC (Dentistry in Service to Communities) program. The following strategies are described as ways to enrich community-based learning experiences for dental students: photographic documentation; written narratives; critical incident reports; and mentored post-experiential small group discussions. Fieldwork and course-related examples are drawn from community-based dental experiences to illustrate how reflective teaching approaches can enhance student learning. A directed process of reflection is suggested as a way to increase the impact of the community learning experience. 相似文献
85.
Sandler A Scott D Azuhata T Takamizawa S O'Dorisio S 《Journal of pediatric surgery》2002,37(3):507-511
Background/Purpose: Several clinical and biologic features of neuroblastoma (NB) are used to predict the risk of recurrent disease. The balance between antiapoptotic and proapoptotic factors within a tumor may affect its ability to survive. Survivin is an antiapoptotic factor expressed in highly proliferative NB, whereas Fas is a proapoptotic factor that portends a favorable prognosis. The authors determined whether the ratio of survivin to Fas (S:F ratio) is predictive of recurrent disease in patients with NB. The authors previously have shown the S:F ratio is predictive of recurrent disease in pediatric renal tumors. Methods: The authors quantified the levels of 9 different apoptotic mRNA species using Rnase Protection assay (RPA, Riboquant, PharMingen, San Diego, CA). Twenty-eight primary tumor specimens were evaluated from patients with ganglioneuroma (n = 3), ganglioneuroblastoma (n = 2), and neuroblastoma (n = 23) from tumors of all clinical stages obtained at the time of diagnosis. mRNA levels were calculated as a percentage of L32 for each specimen assayed, and positive expression was assumed to be greater than 10% of L32. Results: Survivin was expressed in 90% of tumors that went on to recur and only in 27.7% of those that were cured. The S:F ratio was significantly greater in tumors that went on to recur (n = 10) compared with those from patients that were cured (n = 18) (median S:F ratio, 3.3 v 0.75; P = .0002, Wilcoxon rank-sum test). A cutoff ratio of 2.3 was highly predictive of tumor recurrence irrespective of clinical stage of disease (area under ROC curve = 0.906). Sensitivty was 80% (CI, 44.4% to 97.5%), specificty was 94.4% (CI, 72.7% to 99.9%), positive predictive value was 88.9% (CI, 51.8% to 99.7%), and negative predictive value was 89.5% (66.9% to 98.7%). Twenty-five of 28 (89.3%) tumor ratios were correct in predicting outcome. Conclusions: The survivin: Fas ratio in primary tumors may be used to predict the risk for recurrent disease in patients with NB. The S:F ratio appears to be a more sensitive predictor of recurrent disease than survivin expression alone. Determining this ratio may not only be helpful in guiding follow-up of patients with NB, but also may aid in stratifying patients for more aggressive therapeutic strategies. 相似文献
86.
87.
Sjögren B Gunnare S Sandler H 《Scandinavian journal of work, environment & health》2002,28(3):205-207
After exposure to decomposed chlorodifluoromethane (freon-22), a 65-year-old man developed respiratory symptoms such as cough, blood-stained sputum, and increasing dyspnea. Three weeks later, his family doctor diagnosed infectious bronchitis. Another week later he died due to myocardial infarction. The discussion focuses on an inflammatory process caused by the inhalation of decomposed freon and its possible association with myocardial infarction. 相似文献
88.
Hanna N Ansari R Fisher W Shen J Jung SH Sandler A 《Lung cancer (Amsterdam, Netherlands)》2002,35(3):293-297
Results of a previous Hoosier Oncology Group (HOG) study revealed a small survival advantage for VIP versus etoposide and cisplatin (EP) for patients with extensive stage small cell lung cancer (SCLC). This phase II study evaluated VIP with concurrent thoracic radiotherapy in patients with limited stage SCLC. Eligible patients had a Karnofsky Performance Score > or = 50, no prior chemotherapy or radiotherapy, and adequate end organ function. Fifty-three patients were entered. Radiotherapy was given as a daily fraction of 1.8 Gy, five fractions per week for 5 weeks for a total dose of 45 Gy, beginning on day 1 of VIP. The first 13 patients received etoposide 75 mg/m(2), cisplatin 20 mg/m(2), and ifosfamide 1.2 g/m(2) on days 1-4 with Mesna every 3 weeks for four cycles unless the patient demonstrated disease progression or undue toxicity. Excessive toxicity was seen in the first 13 patients; therefore, VIP was modified by deleting the 4th day for all subsequent patients. The major toxicity in this trial was myelosuppression. Grade 3/4 anemia, granulocytopenia, and thrombocytopenia occurred in 38, 75, and 34% of patients, respectively. There were four treatment-related deaths [three patients (23%) on the 4-day regimen and one patient (2.5%) on the 3-day regimen]. Twenty-five patients (47.2%) achieved a CR and 11 patients (20.8%) had a PR for an overall response rate of 68%. Minimum follow up for all patients is 5 years. Overall, 46 of 53 patients have died. Median, 1, 2 and 5 year overall survival for the entire group is 15.1 months, 69.8, 35.9, and 13.2, respectively. The results of this phase II trial of VIP with concurrent early thoracic radiotherapy failed to demonstrate a superior response rate over other series utilizing EP. In addition, treatment-related morbidity and mortality appears to be unacceptably high with the VIP regimen. 相似文献
89.
Bhatia S Hanna N Ansari R Einhorn L Sandler A 《Lung cancer (Amsterdam, Netherlands)》2002,38(1):85-89
Chemoradiation is standard treatment for patients with unresectable locally advanced non-small cell lung cancer (NSCLC). However, local and distant relapse rates remain high. It has been postulated that the addition of consolidation chemotherapy might further decrease the systemic relapse rate. We performed this phase II study to evaluate the toxicities and activity of two cycles of paclitaxel and carboplatin administered prior to and following thoracic radiation in patients with locally advanced, inoperable NSCLC. From April to December 1997, 25 patients were entered on study. Twenty-three patients were eligible and received paclitaxel 225 mg/m(2) intravenously over 3 h followed by carboplatin at an AUC (6) on days 1 and 22. Radiation consisted of 60 Gy given over 6 weeks beginning on day 43. Patients with non-progressive disease received two additional cycles of consolidation carboplatin and paclitaxel. Four of 23 patients progressed during induction chemotherapy. There were seven PR's and 11 had SD after induction chemotherapy. Following radiation, the response changed to 11 PR, four SD, and three had progressive disease. Of the 15 patients eligible to receive consolidation chemotherapy, three were excluded due to a poor performance status. Twelve patients were treated with consolidation chemotherapy with further improvement in two patients (SD to PR, PR to CR). All 12 patients who received consolidation chemotherapy developed grade 3 or 4 neutropenia, including three patients with neutropenic fever. The overall response rate was 52.1%. The median survival, 1-, and 2-year survival was 10.5 months, 45, and 17%, respectively. In conclusion, consolidation chemotherapy was associated with significant hematologic toxicity without an obvious improvement in survival in comparison to other studies utilizing chemoradiation alone. 相似文献
90.
Sandler A 《Clinical lung cancer》2002,4(Z1):S30-S34
Small-cell lung cancer (SCLC) is a particularly aggressive form of lung cancer and is associated with a poor prognosis, rapid tumor growth, and early metastasis. Currently, the cornerstone of treatment in SCLC consists of combination therapy, with platinum/etoposide being the regimen of choice. Unfortunately, even with these advances in treatment, the median survival for patients with limited-stage disease is 10-15 months and 7-11 months for patients with extensive-stage disease. New treatment mechanisms need to be explored in order to extend the survival of SCLC patients. One such new treatment is the topoisomerase I inhibitor, irinotecan. This drug represents a promising advancement in the treatment of SCLC. 相似文献