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991.
Lee AW Kwong DL Leung SF Tung SY Sze WM Sham JS Teo PM Leung TW Wu PM Chappell R Peters LJ Fowler JF 《International journal of radiation oncology, biology, physics》2002,53(1):75-85
PURPOSE: To study the factors affecting the risk of symptomatic temporal lobe necrosis after different fractionation schedules. METHODS AND MATERIALS: One thousand thirty-two patients with T1-2 nasopharyngeal carcinoma treated with radical radiotherapy in Hong Kong during 1990-1995 were studied. They were treated at four different centers with similar techniques but different fractionation schedules: 984 patients were given 1 fraction daily throughout (q.d.), and 48 patients were irradiated twice daily (b.i.d.) for part of the course. The median total dose was 62.5 Gy (range 50.4-71.2), dose per fraction was 2.5 Gy (range 1.6-4.2), and overall treatment time (OTT) was 44 days (range 29-70). In addition, 500 patients received supplementary doses for parapharyngeal extension, 113 received booster doses by brachytherapy, and 114 received sequential chemotherapy using cisplatin-based regimes. RESULTS: Altogether, 24 patients developed symptomatic temporal lobe necrosis: 18 from the q.d. group and 6 from the b.i.d. group. The 5-year actuarial incidence ranged from 0% (after 66 Gy in 33 fractions within 44 days) to 14% (after 71.2 Gy in 40 fractions within 35 days). Multivariate analyses showed that the risk was significantly affected by the fractional effect of the product of total dose and dose per fraction (hazard ratio [HR] = 1.04, 95% confidence interval [CI] 1.02-1.05), OTT (HR 0.88, 95% CI 0.80-0.97), and b.i.d. scheduling (HR 13, 95% CI 3-54). Repeating the analyses for patients treated with the q.d. schedules confirmed the independent significance of OTT in addition to the product of total dose and dose per fraction. CONCLUSION: The tentative results suggest that in addition to fractional dose, the OTT also had significant impact on the risk of temporal lobe necrosis, and b.i.d. scheduling increased the hazard further. 相似文献
992.
Stewart KD Martinez AA Weiner S Podratz K Stromberg JS Schray M Mitchell C Sherman A Chen P Brabbins DA 《International journal of radiation oncology, biology, physics》2002,54(2):527-535
PURPOSE: To evaluate the long-term results of treatment using adjuvant whole abdominal irradiation (WAPI) with a pelvic/vaginal boost in patients with Stage I-III endometrial carcinoma at high risk of intra-abdominopelvic recurrence, including clear cell (CC) and serous-papillary (SP) histologic features. METHODS AND MATERIALS: In a prospective nonrandomized trial, 119 patients were treated with adjuvant WAPI between November 1981 and April 2000. All patients were analyzed, including those who did not complete therapy. The mean age at diagnosis was 66 years (range 39-88). Thirty-eight patients (32%) had 1989 FIGO Stage I-II disease and 81 (68%) had Stage III. The pathologic features included the following: 64 (54%) with deep myometrial invasion, 48 (40%) with positive peritoneal cytologic findings, 69 (58%) with high-grade lesions, 21 (18%) with positive pelvic/para-aortic lymph nodes, and 44 (37%) with SP or CC histologic findings. RESULTS: The mean follow-up was 5.8 years (range 0.2-14.7). For the entire group, the 5- and 10-year cause-specific survival (CSS) rate was 75% and 69% and the disease-free survival (DFS) rate was 58% and 48%, respectively. When stratified by histologic features, the 5- and 10-year CSS rate for adenocarcinoma was 76% and 71%, and for serous papillary/CC subtypes, it was 74% and 63%, respectively (p = 0.917). The 5- and 10-year DFS rate for adenocarcinoma was 60% and 50% and was 54% and 37% serous papillary/CC subtypes, respectively (p = 0.498). For surgical Stage I-II, the 5-year CSS rate was 82% for adenocarcinoma and 87% for SP/CC features (p = 0.480). For Stage III, it was 75% and 57%, respectively (p = 0.129). Thirty-seven patients had a relapse, with the first site of failure the abdomen/pelvis in 14 (38%), lung in 8 (22%), extraabdominal lymph nodes in 7 (19%), vagina in 6 (16%), and other in 2 (5%). When stratified by histologic variant, 32% of patients with adenocarcinoma and 30% with the SP/CC subtype developed recurrent disease. Most failures for either histologic group occurred within the abdominopelvic region. However, one-third of the adenocarcinoma recurrences were in the lung. Multivariate regression analysis (age, surgical stage, grade, myometrial invasion, histologic type, lymph node status, and peritoneal cytology) demonstrated age (p = 0.019) and surgical stage (p = 0.036) to be of prognostic significance for CSS; age (p = 0.036) was the only significant prognostic factor for DFS. Grade 1-2 gastrointestinal and hematologic acute toxicities were common. Asymptomatic bibasilar scarring on chest X-ray and mild elevation of liver enzymes were seen in almost 50% of the patients. Even though chronic toxicities were less frequent, 12% developed Grade 3-4 gastrointestinal and 2% Grade 3 renal toxicities. CONCLUSION: Adjuvant WAPI is very effective treatment with excellent 10-year results for Stage I-III endometrial carcinoma with risk factors for intra-abdominopelvic recurrence, including SP or CC histologic variants, deep myometrial invasion, high grade, nodal involvement, and positive peritoneal cytology. The low long-term complication rate with high CSS rate makes WAPI the treatment of choice for these patients with significant comorbidities. 相似文献
993.
Dekker MC Nunn RJ Einfeld SE Tonge BJ Koot HM 《Journal of autism and developmental disorders》2002,32(6):601-610
The objective of the reported study was to reassess the factor structure of the Developmental Behaviour Checklist (DBC) in a large cross-cultural sample representing all levels of intellectual disability. Parent and teacher DBC ratings on a combined sample of 1536 Dutch and Australian children and adolescents (ages 3–22) with mild to profound intellectual disability were used. Principal components analyses produced five subscales: Disruptive/Antisocial, Self-Absorbed, Communication Disturbance, Anxiety, and Social Relating, explaining 43.7% of the total variance. Internal consistencies of these subscales ranged from .66 to .91. The revised factor structure of the DBC appears to be an improved and useful tool for assessing emotional and behavioral problems in children with intellectual disabilities. 相似文献
994.
Objective
To determine the association between CCR5 and CCR2b genotype and the clinical manifestation of first and subsequent AIDS‐defining illnesses (ADIs).Methods
The distribution of ADIs was examined by CCR5 and CCR2b genotype in a subset of homosexual men enrolled in the Sydney AIDS Prospective Study. The expected number of ADIs was calculated from rates observed in the same tertiary hospital over the same period.Results
Information on initial ADI was collected for 117 homosexual men diagnosed with AIDS before January 1998. Of these individuals, 17 were heterozygous for the CCR5‐DΔ32 mutation and 11 were heterozygous for CCR2b‐64I. The number of observed cases of Pneumocystis carinii pneumonia (PCP), toxoplasmosis, Mycobacterium avium complex (MAC) and cryptosporidiosis reported as a first ADI was substantially fewer in people heterozygous for the CCR5‐DΔ32 mutation than for those without the mutation, despite similar age, CD4 T‐cell count at AIDS diagnosis, year of AIDS diagnosis and receipt of antiretroviral treatment. In addition, among individuals heterozygous for CCR5‐DΔ32 there were fewer cases of PCP, toxoplasmosis, MAC, and cryptosporidiosis observed as subsequent ADIs compared to the number expected, based on rates measured in the same hospital during the same period (seven observed vs. 24 expected, RR = 0.3, 95% CI = 0.01–0.6). The distribution of first and subsequent ADIs did not differ from the number expected in individuals heterozygous for the CCR2b‐64I mutation.Conclusion
Results from this study show that heterozygosity for CCR5‐DΔ32 but not CCR2b‐64I appears to protect against opportunistic infections.995.
Stewart JM 《Heart disease (Hagerstown, Md.)》2002,4(1):33-39
Transient orthostatic hypotension is a common experience of many healthy adolescents and is the expected outcome of relatively dilated-dependent vascular tone. These children may experience brief symptoms of orthostatic intolerance when standing up rapidly, but they have no chronic symptoms or diseases. However, persistent orthostatic hypotension and chronic symptoms of orthostatic intolerance indicate postural tachycardia syndrome. 相似文献
996.
Jorizzo J Stewart D Bucko A Davis SA Espy P Hino P Rodriguez D Savin R Stough D Furst K Connolly M Levy S 《Cutis; cutaneous medicine for the practitioner》2002,70(6):335-339
The efficacy and safety of a new 0.5% fluorouracil topical cream were compared with vehicle control for the treatment of actinic keratosis (AK). Active treatment applied once daily for 1, 2, or 4 weeks was more effective than vehicle control in achieving reduction from baseline in lesion counts and lesion clearance. Active treatment also resulted in significantly better global assessments of overall improvement. Treatment was effective regardless of the number of baseline lesions. Although longer treatment duration correlated with greater efficacy, treatment for 1, 2, or 4 weeks was effective. This new microsphere-based fluorouracil formulation was generally well tolerated; adverse events were primarily limited to facial irritation that resolved quickly after treatment. This new treatment provides a safe alternative to the topical fluorouracil formulations currently available for the 1-, 2-, or 4-week treatment of AK. 相似文献
997.
DeLisi LE Shaw SH Crow TJ Shields G Smith AB Larach VW Wellman N Loftus J Nanthakumar B Razi K Stewart J Comazzi M Vita A Heffner T Sherrington R 《The American journal of psychiatry》2002,159(5):803-812
OBJECTIVE: Some genome-wide scans and association studies for schizophrenia susceptibility genes have yielded significant positive findings, but there is disagreement between studies on their locations, and no mutation has yet been found in any gene. Since schizophrenia is a complex disorder, a study with sufficient power to detect a locus with a small or moderate gene effect is necessary. METHOD: In a genome-wide scan of 382 sibling pairs with a diagnosis of schizophrenia or schizoaffective disorder, 396 highly polymorphic markers spaced approximately 10 centimorgans apart throughout the genome were genotyped in all individuals. Multipoint nonparametric linkage analysis was performed to evaluate regions of the genome demonstrating increased allele sharing, as measured by a lod score. RESULTS: Two regions with multipoint maximum lod scores suggesting linkage were found. The highest lod scores occurred on chromosome 10p15-p13 (peak lod score of 3.60 at marker D10S189) and the centromeric region of chromosome 2 (peak lod score of 2.99 at marker D2S139). In addition, a maximum lod score of 2.00 was observed with marker D22S283 on chromosome 22q12, which showed evidence of an imprinting effect, whereby an excess sharing of maternal, but not paternal, alleles was present. No evidence of linkage was obtained at several locations identified in previous studies, including chromosomes 1q, 4p, 5p-q, 6p, 8p, 13q, 15p, and 18p. CONCLUSIONS: The findings of this large genome-wide scan emphasize the weakness and fragility of linkage reports on schizophrenia. No linkage appears to be consistently replicable across large studies. Thus, it has to be questioned whether the genetic contribution to this disorder is detectable by these strategies and the possibility raised that it may be epigenetic, i.e., related to gene expression rather than sequence variation. Nevertheless, the positive findings on chromosome 2, 10, and 22 should be pursued further. 相似文献
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