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71.
Purpose: Recent randomized trials have suggested that improved local-regional control after radiation therapy significantly increases survival for breast cancer patients with positive axillary nodes treated with adjuvant systemic therapy (1, 2). It has been our policy to use a third radiation field only in patients with 4 or more positive nodes. The purpose of this study was to assess whether there are any clinical or pathologic factors associated with an increased risk of regional nodal failure (RNF) in patients with 0–3 positive nodes treated with tangential radiotherapy (RT) alone with or without systemic therapy.

Methods and Materials: We retrospectively analyzed the incidence of RNF for 691 patients with clinical Stage I or II invasive breast cancer treated with complete gross excision of the primary tumor and tangential RT alone between 1978–87; 12% also received systemic therapy. All had 0–3 positive nodes on axillary dissection that had histologic examination of ≥ 6 nodes, and all had potential 8-year follow-up. The median number of axillary nodes removed was 11 (range 6–36). RNF was defined as any recurrence in ipsilateral axillary, internal mammary, supraclavicular, or infraclavicular nodes in the absence of recurrence in the breast, with or without simultaneous distant metastasis. Crude rates for first sites of failure within the first 8 years after treatment were calculated. A polychotomous logistic regression was used to identify factors prognostic for RNF and other sites of first failure.

Results: Within 8 years, RNF was the first site of failure for 27 patients for a crude 8-year rate of 3.9%. Isolated axillary failure occurred in 8 patients (1.2%). Isolated supraclavicular and/or infraclavicular failure occurred in 5 (1.3%) and 3 (0.4%) patients, respectively. Isolated internal mammary node failure occurred in 2 patients (0.3%). A polychotomous logistic regression model of first site of failure (local failure, regional nodal, distant/opposite breast, dead without recurrence, no evidence of disease) within 8 years found age <50 years, moderate or marked necrosis, size greater than 1 cm, and presence of an extensive intraductal component (EIC) to be significantly correlated with site of first failure, but only the last two were associated with a significantly larger relative risk of RNF versus being no evidence of disease at 8 years. The incidence of RNF was 0.7% for patients with tumors ≤ 1 cm compared to 5.7% among patients with larger tumors. Among patients with EIC-positive tumors the incidence of RNF was 7.6% compared to 3.1% among those whose tumors were EIC-negative.

Conclusions: Although the incidence of RNF has been shown to be somewhat higher in patients with tumors measuring greater than 1 cm and those with an EIC, RNF is uncommon among all subsets of patients with negative or 1–3 positive lymph nodes treated with conservative surgery, axillary dissection, and only tangential RT fields. Therefore, giving only tangential RT (without a separate nodal field) appears generally acceptable for patients with 0–3 positive nodes.  相似文献   

72.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis.  相似文献   
73.
Fetal movements were measured by 37 pregnant women during a 10-minute period while they were lying on their left side at various times during the day with the highest rates in the evening. Preliminary assessments of fetal movement and serum hPL levels in pregnant women suggest that the two tests might complement each other in providing more information about the status of the placenta and fetus.  相似文献   
74.
Gelman J  Rodriguez E 《The Journal of urology》2007,177(1):188-91; discussion 191
PURPOSE: We report our 8-year experience with 1-stage open urethral reconstruction in 10 patients with recurrent bulbar and/or membranous strictures after UroLume urethral stent placement. MATERIALS AND METHODS: Ten consecutive referral patients underwent preoperative contrast imaging and urethroscopy followed by primary anastomotic repair or substitution urethroplasty, with concomitant open UroLume removal (when the stent was still present). Postoperative evaluation included contrast imaging 3 weeks after surgery, urethroscopy 4 months after surgery, uroflowmetry, and American Urological Association symptom score assessment. RESULTS: At a medium followup of 51.2 months all patients remain free of bulbar or membranous stricture recurrence. No patient has required dilation or any other intervention. CONCLUSIONS: One-stage open reconstruction with stent extraction offers a definitive treatment option with a high success rate for patients with recurrent bulbar and/or membranous strictures following urethral stent placement.  相似文献   
75.
SARS-CoV isa newly identified coronavirus that causes severe acute respiratory syndrome (SARS). Currently, there is no effective method available for prophylaxis and treatment of SARS-CoVinfections. In the present study, the influence of small interfering RNA (siRNA) on SARS-CoV nucleocapsid (N) protein expression was detected in cultured cells and mouse muscles. Four siRNA expression cassettes driven by mouse U6 promoter targeting SARS-CoV N gene were prepared, and their inhibitory effects on expression of N and enhanced green fluorescence protein (EGFP) fusion protein were observed.  相似文献   
76.
0 引言 人类免疫缺陷病毒 (human immunodeficiencyvirus,HIV) - 1编码的反式激活蛋白 TAT具有独特的跨膜运转方式 ,而且有转导速度快 ,效率高的特点 ,被称为蛋白转导结构域 (protein transduction domain,PTD) [1 ,2 ] .本研究用PCR扩增了慢性粒细胞白血病慢粒 bcr/ abl融合蛋白的基因片段 ,在其 5′端融合 PTD结构域的编码区后在大肠杆菌中进行了表达 .表达产物经纯化后 ,加入培养的 HL 6 0细胞 ,表达的蛋白可直接进入细胞内 .这一结果为用外源蛋白负载(L oading)免疫细胞提供了新的途径 .1 材料和方法1.1  DNA重组 人工合…  相似文献   
77.
Background Effective antiretroviral therapy (ART) has reduced the incidence of HIV-associated neurocognitive impairment (HNCI) but its prevalence remains high. Clinical trials have yet to identify a consistently effective treatment for HNCI, other than ART, but in vitro data support that some drugs approved by the Food and Drug Administration (FDA) for other indications might benefit individuals with HNCI. Some of these drugs, such as serotonin reuptake inhibitors (SRIs) and HMG-CoA reductase inhibitors (statins), may do so by reducing HIV replication in the CNS and are already widely used by HIV-infected individuals. Methods Six-hundred fifty-eight HIV-infected participants of the CHARTER cohort had a baseline assessment, which included comprehensive neuropsychological (NP) testing and HIV RNA measurements in plasma and cerebrospinal fluid (CSF). Four-hundred sixty-seven (71%) subjects used ART, 195 (30%) used SRIs, and 63 (10%) used statins. Results SRI users were less likely to have HIV RNA levels in CSF above 50 copies (c)/mL (29 vs. 37% in non-SRI users, OR 0.69, p = 0.05). This association was most evident for three of the seven SRIs (citalopram, sertraline, and trazodone, or “antiviral” SRIs, combined 25 vs. 38% in non-SRI users, OR 0.56, p = 0.01) and was strongest in those not taking concomitant ART (61 vs. 83%, OR 0.31, p = 0.01). “Antiviral” SRI users also performed better on NP tests (median global deficit score 0.37 vs. 0.47, p = 0.04). Statin users were also less likely to have HIV RNA levels in CSF above 50 c/mL (16 vs. 37%, p < 0.001) but, in contrast to SRIs, the association was strongest in those taking ART (2 vs. 18%, p < 0.001). Statin use was not associated with better NP performance. Multivariate analyses indicated that the use of “antiviral” SRIs—but not statins—was associated with undetectable HIV RNA levels in CSF and better NP performance. Conclusions SRIs may reduce HIV replication in CSF and improve NP performance. This was particularly true for three SRIs—supporting differences in antiviral efficacy between drugs—in individuals who were not taking ART. In contrast, statins were not associated with lower HIV replication in CSF in multivariate analyses and were not associated with better NP performance. These analyses support the value of large observational cohort studies in identifying FDA-approved drugs that may be worth further investigation.  相似文献   
78.
We examined the interrater (IRR) of clinical ratings of neuropsychological (NP) impairment and neurocognitive diagnoses in HIV. Thirty participants with advanced HIV-infection who were enrolled in a multicenter HIV brain banking research project underwent comprehensive NP and neuromedical evaluations. Using a standardized system of guidelines, neuropsychologists from six participating sites independently assigned clinical ratings of NP impairment, as well as multilevel diagnoses reflecting the inferred etiology of the impairments and their effects on everyday functioning. Findings indicated excellent IRR in rating the presence and severity of NP impairment, but overall modest IRR for neurocognitive diagnoses. Not surprisingly, most diagnostic disagreements concerned the etiology of impairments in persons with medical and neuropsychiatric risk factors in addition to HIV.  相似文献   
79.
巫山淫羊藿的化学研究   总被引:8,自引:0,他引:8  
从小檗科Berberidaceae淫羊藿属Epimedium植物巫山淫羊藿Epimedium wushanense T.S.Ying的地上部分中分得两种黄酮甙单体,经理化性质鉴定及紫外、红外、质谱、氢谱、碳谱等光谱分析,确定甙Ⅰ是新化合物,命名为巫山淫羊藿甙(wushanicariin)。甙Ⅱ是已知化合物淫羊藿甙(icariin),系首次从该种植物中分离。  相似文献   
80.
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