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991.
Background The purpose of this study was to evaluate the significance of pathologic nodal assessment and extent of nodal metastases on patient outcome in patients with pancreatic adenocarcinoma. Materials and Methods A prospectively maintained pancreatic cancer database was reviewed, and 696 consecutive patients were identified who underwent resection for pancreatic adenocarcinoma between 1995 and 2005. Overall survival was compared to lymph node (LN) status, absolute number of pathologically assessed LN, and LN ratio expressed as the number of positive LN to the total LN assessed. Results Of the 696 patients, 598 (86%) had pancreaticoduodenectomy (PD), and 96 (14%) had distal pancreatectomy (DP). For all patients, median follow-up was 13 months (range, 0–122 months), and estimated 5-year survival was 16%. A total of 243 (35%) patients were LN-negative (N0) and had a median survival of 27 months. When assessed as a continuous variable, the number of pathologically assessed LN did not correlate with survival for N0 patients undergoing either PD or DP. The median survival for the 453 patients with node-positive (N1) disease was 16 months. When analyzed as a continuous variable, the absolute number of positive LNs was a significant predictor of survival for N1 patients with a linear relationship up to eight positive LNs. LN ratio, as a continuous variable, also predicted survival with a linear relationship up to a ratio of 0.35. A ratio of 0.18 was associated with a 19-month median survival and served as the best cutoff, p < 0.01. Conclusions The absolute number of positive LNs and LN ratio are strong predictors of survival for patients with node-positive pancreatic adenocarcinoma. Inadequate surgical lymphadenectomy or pathologic LN assessment understages node-negative patients. Presented in part at the 48th Annual Meeting of the Society for Surgery of the Alimentary Tract, May 22, 2007, Washington, DC.  相似文献   
992.
Introduction The purpose of this study was to compare rates and patterns of disease progression following percutaneous, image-guided radiofrequency ablation (RFA) and nonanatomic wedge resection for solitary colorectal liver metastases. Methods We identified 30 patients who underwent nonanatomic wedge resection for solitary liver metastases and 22 patients who underwent percutaneous RFA because of prior major hepatectomy (50%), major medical comorbidities (41%), or relative unresectability (9%). Serial imaging studies were retrospectively reviewed for evidence of local tumor progression. Results Patients in the RFA group were more likely to have undergone prior liver resection, to have a disease-free interval greater than 1 year, and to have had an abnormal carcinoembryonic antigen (CEA) level before treatment. Two-year local tumor progression-free survival (PFS) was 88% in the Wedge group and 41% in the RFA group. Two patients in the RFA group underwent re-ablation, and two patients underwent resection to improve the 2-year local tumor disease-free survival to 55%. Approximately 30% of patients in each group presented with distant metastasis as a component of their first recurrence. Median overall survival from the time of resection was 80 months in the Wedge group vs 31 months in the RFA group. However, overall survival from the time of treatment of the colorectal primary was not significantly different between the two groups. Conclusions Local tumor progression is common after percutaneous RFA. Surgical resection remains the gold standard treatment for patients who are candidates for resection. For patients who are poor candidates for resection, RFA may help to manage local disease, but close follow-up and retreatment are necessary to achieve optimal results. Presented at the Society for Surgery of the Alimentary Tract 47th Annual Meeting, May 22, 2006, Los Angeles, California. White and Avital contributed equally.  相似文献   
993.
CD117, a trans-membrane tyrosine kinase receptor, has been immunolocalized in a large variety of human neoplasms. Little, however, is known about the prevalence and clinical implications of CD117 in stage I adenocarcinoma and squamous cell carcinoma of the lung. We evaluated 201 consecutive stage I adenocarcinoma and squamous cell carcinoma of the lung for CD117 immunoreactivity (dichotomized as negative or positive if containing less than 5% or >/=5% immunoreactive neoplastic cells, respectively), also taking into account the pattern (either membranous or cytoplasmic), and the intensity of immunostaining in comparison with intratumoral mast cells. The immunostaining results were then correlated with tumor biopathological characteristics and patients' survival. Membranous CD117 immunoreactivity was documented in 19 (22%) of 88 adenocarcinomas and 15 (13%) of 113 squamous cell carcinomas, whereas cytoplasmic labelling was seen in 28 (32%) adenocarcinomas and eight (7%) squamous cell carcinomas. In both tumor types, membranous or cytoplasmic CD117 immunoreactivity was associated with higher proliferative fraction and with features of more aggressive tumor behavior, including higher stage, size and grade, occurrence of clinical symptoms, high microvessel density and neuroendocrine differentiation. Furthermore, immunoreactive tumors exhibited increased levels of bcl-2, cyclin-E, Her-2, p27(Kip1) and fascin, the latter being a marker of tumor cell metastatization in lung cancer. Membranous but not cytoplasmic labelling emerged as an independent risk factor for death and reduced time to progression in adenocarcinoma but not in squamous cell carcinoma patients, when singly adjusted for confounding factors. CD117 immunoreactivity identifies a peculiar subset of stage I adenocarcinoma and squamous cell carcinoma of the lung with highly proliferative tumors and may have prognostic relevance in adenocarcinoma patients. Targeting the CD117 pathway could be a novel therapeutic strategy in a subset of pulmonary carcinomas.  相似文献   
994.
In this study, we examined the perspectives of patients with Guillain-Barré syndrome during their recovery phase. We used a grounded theory approach. Five patients discharged from a major teaching hospital were interviewed; the format was semi-structured. Data were analyzed through a constant comparative method. We describe the central theme of moving from dependency to independence. There are five phases in the recovery process: experiencing dependency, encountering helplessness, wanting to know more about GBS, discovering inner strength, and regaining independence. Moving from dependency to independence was facilitated by the patients' discovery of their inner strengths. Regaining their independence was facilitated by their strong desire to walk out of the hospital. Patients realized that they had little knowledge about their illness and prognosis; further research in this area would be beneficial.  相似文献   
995.
The role of serum uric acid as an independent risk factor for cardiovascular and renal morbidity is controversial. A better understanding of its relationship with preclinical organ damage may help clarify the mechanism(s) implicated in the development of early cardiovascular disease. We evaluated the association between uric acid and the presence and degree of target organ damage in 425 (265 males, 160 females) middle-aged, untreated patients with essential hypertension. Left ventricular mass index and carotid intima-media thickness were assessed by ultrasound scan. Albuminuria was measured as the albumin to creatinine ratio in 3 nonconsecutive first morning urine samples. Overall, patients with target organ damage had significantly higher levels of serum uric acid as compared with those without it (presence versus absence of left ventricular hypertrophy, P=0.04; carotid abnormalities, P<0.05; microalbuminuria, P<0.004; and at least 1 versus no organ damage, P<0.03). In women, the occurrence and severity of each target organ damage we examined increased progressively from the lower to the upper serum uric acid tertiles (P<0.01). After adjustment for body mass index, age, creatinine clearance, and high-density lipoprotein cholesterol, each standard deviation increase in serum uric acid entailed a 75% higher risk of having cardiac hypertrophy and a 2-times greater risk of having carotid abnormalities. These results support the role of serum uric acid as an independent, modifiable marker of cardiovascular damage.  相似文献   
996.
It is presently unknown what the real impact of clinical acupuncture research on practitioners is, or what kind of specific information clinicians need to find on a published paper in this field. OBJECTIVES: To develop a pilot survey instrument to evaluate clinicians' information needs when reading acupuncture research papers, and then to use it to assess the relative importance that specific clinical details may have for clinicians when reading papers on the areas of acupuncture treatment for migraine/headaches and nausea/vomiting. METHODS: The survey instrument consisted of a list of 50 clinical details grouped in four areas: practitioners, patients, diagnostic procedures, and acupuncture treatment. Questions about the relative importance of these details regarding acupuncture research in general, and on the areas of migraine/headaches and nausea/vomiting in particular, were answered by 34 medical acupuncture practitioners attending a conference. RESULTS: Most clinical details were deemed important, with the highest rating for details concerning the acupuncture treatment (M = 3.25 +/- 0.43 on a scale from 0 = not at all important to 4 = very important), and diagnostic procedures (M = 2.91 +/- 0.33). Similar results applied to the research on migraine/headaches and nausea/vomiting. CONCLUSION: For acupuncture clinical research to have a real impact in daily practice, researchers need to be sensitive to the needs of clinicians and provide enough information about clinical details on the published papers. A survey instrument like this seems to be an appropriate tool to gather information about clinicians' needs.  相似文献   
997.
998.
Predicting which individuals may engage in aggressive behavior is of interest in today’s society; however, there is little data on the neural basis of aggression in healthy individuals. Here, we tested whether regional differences in white matter (WM) microstructure were associated with later reports of aggressive tendencies. We recontacted healthy young adults an average of 3 years after they underwent research MRI scans. Via electronic survey, we administered the Buss Perry Aggression Questionnaire. We divided aggression into Aggressive Thoughts (Anger and Hostility subscales) and Aggressive Acts (Verbal and Physical subscales) and used Tract-Based Spatial Statistics to test the relationship of those measures to WM microstructure. In 45 individuals age 15–30 at baseline, we observed significant relationships between Aggressive Acts and fractional anisotropy (FA) in a parietal region consistent with the superior longitudinal fasciculus (SLF). As the SLF has an established relationship to executive function, we performed an exploratory analysis in a subset of individuals with working memory data. Decreased FA in executive network regions, as well as working memory performance, were associated with later self-reported aggressive tendencies. This has implications for our healthy behavior understanding of as well as that of patient populations known to have executive dysfunction.  相似文献   
999.
Metastatic melanoma is associated with a poor prognosis, but no method reliably predicts which melanomas of a given stage will ultimately metastasize and which will not. While sentinel lymph node biopsy (SLNB) has emerged as the most powerful predictor of metastatic disease, the majority of people dying from metastatic melanoma still have a negative SLNB. Here we analyze pump-probe microscopy images of thin biopsy slides of primary melanomas to assess their metastatic potential. Pump-probe microscopy reveals detailed chemical information of melanin with subcellular spatial resolution. Quantification of the molecular signatures without reference standards is achieved using a geometrical representation of principal component analysis. Melanin structure is analyzed in unison with the chemical information by applying principles of mathematical morphology. Results show that melanin in metastatic primary lesions has lower chemical diversity than non-metastatic primary lesions, and contains two distinct phenotypes that are indicative of aggressive disease. Further, the mathematical morphology analysis reveals melanin in metastatic primary lesions has a distinct “dusty” quality. Finally, a statistical analysis shows that the combination of the chemical information with spatial structures predicts metastatic potential with much better sensitivity than SLNB and high specificity, suggesting pump-probe microscopy can be an important tool to help predict the metastatic potential of melanomas.OCIS codes: (170.3880) Medical and biological imaging, (180.5810) Scanning microscopy, (320.7150) Ultrafast spectroscopy  相似文献   
1000.
Background: Balance is one of the risk factors for falls in older adults. The use of smartphone applications (apps) related to health (mHealth) is increasing and, while there is potential for apps to be used as a self-managed balance intervention, many healthcare providers are concerned about the content and credibility of mHealth apps overall.

Purpose: This study evaluates the quality of balance promoting apps and identifies strengths and areas of concern to assist healthcare providers in recommending these resources.

Materials and methods: Balance apps for the general public, offered on the iPhone Operating System (iOS) and Android platforms, were evaluated using the Mobile Application Rating Scale (MARS).

Results: Five iOS apps met the inclusion criteria. The mean scores for each of the domains in MARS were: Engagement (3.32), Information (3.7), Functionality (3.8), and Esthetics (3.8). Overall, one app (UStabilize) received a rating of 4.43 in MARS five-point scale, which was considered “good”. Other apps in the review demonstrated acceptable quality.

Conclusions: The reviewed balance apps targeted to improve or maintain physical balance were of acceptable quality. Apps address many current issues older adults have to accessing rehabilitation services and, as such, may be particularly useful for this group. Future research should focus on assessing and comparing app efficacy. Development of balance apps for the Android platform is also necessary.

  • Implications for Rehabilitation
  • Given the availability and accessibility of various mHealth apps and the increasing mobile device usage among older adults, mobile apps are a promising avenue for delivering rehabilitation interventions, such as balance training, to older adults.

  • Smartphone apps exist for balance training but overall confidence in health apps within the healthcare community is low and rigorous evaluation is required.

  • A range of apps exist that demonstrate acceptable to good quality and stakeholders should work towards having these apps listed in credible mHealth clearinghouses.

  相似文献   
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