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991.
Background: Metastatic breast cancer is generally believed to be associated with a poor prognosis. Therapeutic advances over the past two decades, however, have resulted in improved outcomes for selected patients with limited metastatic disease. Methods: Between March 1991 and October 2002, 31 patients had hepatic resection for breast cancer metastases limited to the liver. Clinical and pathologic data were collected prospectively from breast and hepatobiliary databases. Results: Median age of patients was 46 years (range, 31 to 70). Liver metastases were solitary in 20 patients and multiple in 11 patients. Median size of the largest liver metastasis was 2.9 cm (range, 1 to 8). Major liver resections (three or more segments resected) were performed in 14 patients, whereas minor resections (fewer than three segments resected) with or without radiofrequency ablation (RFA) were performed in 17 patients. No postoperative mortality occurred. Of the 31 patients, 27 (87%) received either preoperative or postoperative systemic therapy as treatment for metastatic disease. The median survival was 63 months; a single patient died within 12 months of hepatic resection. The overall 2- and 5-year survival rates were 86% and 61%, respectively, whereas the 2- and 5-year disease-free survival rates were 39% and 31%, respectively. No treatment- or patient-specific variables were found to correlate with survival rates. Conclusions: In selected patients with liver metastases from breast cancer, an aggressive surgical approach is associated with favorable long-term survival. Hepatic resection should be considered a component of multimodality treatment of breast cancer in these patients.  相似文献   
992.
PURPOSE: We examined whether preoperative duplex ultrasound scanning (DU) could replace contrast material-enhanced arteriography (CA) in selecting the recipient artery of tibial or peroneal artery bypass grafts. METHODS: In patients who underwent tibial or peroneal artery bypass grafting because of critical ischemia, images were obtained of the lower extremity arterial circulation with both DU and CA. Vascular surgeons, blinded to the operation performed, reviewed either DU or CA images for arterial visualization and patency. The tibial or peroneal artery best suited to receive the bypass graft was selected by surgeons using only data from either DU or CA images. This selection was compared with the artery actually used at bypass surgery. RESULTS: Preoperative DU and CA data for 40 lower extremities in 38 patients undergoing bypass grafting at the level of the tibia provided 110 arteries: 38 anterior tibial arteries, 32 peroneal arteries, and 40 posterior tibial arteries. Ten arteries (8 peroneal, 2 anterior tibial) were not identified with DU, and 1 artery (anterior tibial) was not identified with CA. DU enabled prediction of the artery actually used in 88% of patients (35 of 40), whereas CA enabled prediction of the artery actually used in 93% of patients (37 of 40; P =.59). Duplicate findings at DU and CA enabled selection of 85% of arteries actually used (95% confidence interval, 71%-93%). Arteries used for bypass grafting had significantly higher peak systolic velocity (35 cm/s vs 25 cm/s; P =.04), higher end-diastolic velocity (15 cm/s vs 9 cm/s; P =.005), and greater diameter (2.4 mm vs 1.7 mm; P =.003) compared with arteries not selected for bypass grafting. CONCLUSION: Findings at DU and CA typically agree when used to select tibial or peroneal arteries for bypass grafting. With DU there is occasional difficulty in identification of the peroneal artery, but selection of the actual artery used is accurate. Peak systolic velocity, end-diastolic velocity, and diameter characteristics correlate with arteriographic criteria for tibial bypass target artery selection. If DU enables adequate identification of a target artery for bypass grafting, and especially if the peroneal artery is seen, findings at CA are not likely to alter bypass execution.  相似文献   
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995.
The WHO criteria for osteoporosis are based on bone mineral density (BMD) values in comparison to a reference population of healthy young adults. The aim of this study was to create BMD references for ethnic Swedish women, and to investigate whether the use of these T-score measurements influence the amount of Swedish postmenopausal patients that are diagnosed as having osteoporosis. A bone density reference was created by measuring a population-based sample of 335 randomly selected Swedish women aged 20-39yr. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the lumbar spine, proximal femur, and total body. These locally derived T-score values were subsequently used to diagnose a sample of 300 consecutive postmenopausal Swedish patients referred to the Uppsala Osteoporosis Unit. There was a slight age-dependent decrease in femoral neck BMD, whereas no age effect was seen at other sites such as total hip, lumbar spine, or total body. This suggests that the cohort represents the steady state BMD at the ages of expected peak bone mass in Swedish women. The correlation between BMD measures at different sites differed from r=0.55 (lumbar spine BMD vs femoral neck BMD [FNBMD]) to r=0.92 (total hip BMD vs FNBMD). Central DXA-generated T-scores were calculated from this cohort, and these were significantly higher (0.3-0.5 SD) as compared with manufacturers and NHANESIII reference populations. This indicates that young Swedish women have a higher peak bone mass than the subjects included in the reference populations currently used for clinical measurements. The T-score in total hip derived from the investigated cohort was subsequently used to diagnose 300 clinical patients (mean age 63yr) referred for a DXA scan by their physicians. The use of this locally established and ethnic representative, T-score reference increased the prevalence of osteoporosis in femoral neck and total hip with 53-106%. A Swedish female BMD reference representing peak bone mass has been established and the normative data are presented. Notably, this cohort has considerably higher BMD as compared to the NHANESIII and manufacturer's reference populations. The use of the present T-score reference therefore causes approximately a 2-fold increase in the amount of Swedish postmenopausal women that fulfill the WHO criteria for osteoporosis. This demonstrates the problems with using T-score as diagnostic threshold for osteoporosis and is an argument for future strategies to obtain standardized densitometric cut-offs, for example, mg/cm(2).  相似文献   
996.
The authors report on two gonadotropic carcinomas of the adenohypophysis that occurred in a55-year-old man (Case 1) and a 53-year-old woman (Case 2), with signs of mass effect and amenorrhea, respectively. Both lesions were macroadenomas. The tumor in Case 1 metastasized to dura mater, skull, nasal sinus, and larynx 2 years after patient presentation, whereas that in Case 2 spread to vertebral bodies and ribs after a 19-year latency. Histologically, the primary, recurrent, and metastatic lesions in Case 1 featured brisk mitotic activity and high MIB-1 levels as well as p53 labeling indices. Immunoreactivity for HER-2/neu was assessable only in rare neoplastic cells of the second recurrence and in 80% of cells of the dural metastasis. Low-level HER-2/neu gene amplification was evident in the recurrent tumors and metastasis. The sellar and metastatic tumors in Case 2 resembled benign gonadotropic adenoma with oncocytic change; p53 accumulation, HER-2/neu overexpression, and HER-2/neu gene amplification were not present. The results indicate that low-level amplification of the HER-2/neu gene might be associated with pituitary carcinomas in which more aggressive behavior is seen. Further studies are needed to determine whether HER-2/neu plays a role in the pathogenesis of pituitary carcinoma.  相似文献   
997.
Recent evidence suggests that transition risks from initial clinical high risk (CHR) status to psychosis are decreasing. The role played by remission in this context is mostly unknown. The present study addresses this issue by means of a meta-analysis including eight relevant studies published up to January 2012 that reported remission rates from an initial CHR status. The primary effect size measure was the longitudinal proportion of remissions compared to non-remission in subjects with a baseline CHR state. Random effect models were employed to address the high heterogeneity across studies included. To assess the robustness of the results, we performed sensitivity analyses by sequentially removing each study and rerunning the analysis. Of 773 subjects who met initial CHR criteria, 73% did not convert to psychosis along a 2-year follow. Of these, about 46% fully remitted from the baseline attenuated psychotic symptoms, as evaluated on the psychometric measures usually employed by prodromal services. The corresponding clinical remission was estimated as high as 35% of the baseline CHR sample. The CHR state is associated with a significant proportion of remitting subjects that can be accounted by the effective treatments received, a lead time bias, a dilution effect, a comorbid effect of other psychiatric diagnoses.  相似文献   
998.
999.
BACKGROUND: The aim of our study was to test the hypothesis that amygdala volumes are reduced in patients with recurrent major depression compared with first episode patients. METHODS: Using structural magnetic resonance imaging, we compared 30 inpatients with first-episode depression and 27 inpatients with recurrent major depression (DSM-IV) with healthy volunteer subjects from the local community matched for age, gender, and handedness. RESULTS: Patients with first-episode depression showed enlarged amygdala volumes compared with patients with recurrent major depression and healthy control subjects. No significant differences were found between patients with recurrent depression and healthy control subjects. No significant correlations were found between amygdala volumes and age of onset, illness duration, or severity of depression. CONCLUSIONS: Larger amygdala volumes in patients with first-episode depression may result from higher amygdala metabolism and blood flow. Additionally, disease progression with stress-related excitotoxic processes during recurrent depressive episodes might result in decreased amygdala volumes. Prospective investigations to investigate amygdala changes during the course of depression are needed.  相似文献   
1000.
As London taxi drivers acquire “the knowledge” and develop a detailed cognitive map of London, their posterior hippocampi (pHPC) gradually increase in volume, reflecting an increasing pHPC/aHPC volume ratio. In the mnemonic domain, greater pHPC/aHPC volume ratios in young adults have been found to relate to better recollection ability, indicating that the balance between pHPC and aHPC volumes might be reflective of cross‐domain individual differences. Here, we examined participants' self‐reported use of cognitive map‐based navigational strategies in relation to their pHPC/aHPC hippocampal volume ratio. We find that greater reported cognitive map use was related to significantly greater posterior, relative to anterior, hippocampal volume in two separate samples of young adults. Further, greater reported cognitive map usage correlated with better performance on a self‐initiated navigation task. Together, these data help to advance our understanding of differences between aHPC and pHPC and the greater role of pHPC in spatial mapping.  相似文献   
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