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51.
Unique white matter microstructural patterns in ADHD presentations—a diffusion tensor imaging study 下载免费PDF全文
Alena Svatkova Igor Nestrasil Kyle Rudser Jodene Goldenring Fine Jesse Bledsoe Margaret Semrud‐Clikeman 《Human brain mapping》2016,37(9):3323-3336
Attention‐deficit/hyperactivity disorder predominantly inattentive (ADHD‐PI) and combined (ADHD‐C) presentations are likely distinct disorders that differ neuroanatomically, neurochemically, and neuropsychologically. However, to date, little is known about specific white matter (WM) regions differentiating ADHD presentations. This study examined differences in WM microstructure using diffusion tensor imaging (DTI) data from 20 ADHD‐PI, 18 ADHD‐C, and 27 typically developed children. Voxel‐wise analysis of DTI measurements in major fiber bundles was carried out using tract‐based spatial statistics (TBSS). Clusters showing diffusivity abnormalities were used as regions of interest for regression analysis between fractional anisotropy (FA) and neuropsychological outcomes. Compared to neurotypicals, ADHD‐PI children showed higher FA in the anterior thalamic radiations (ATR), bilateral inferior longitudinal fasciculus (ILF), and in the left corticospinal tract (CST). In contrast, the ADHD‐C group exhibited higher FA in the bilateral cingulum bundle (CB). In the ADHD‐PI group, differences in FA in the left ILF and ATR were accompanied by axial diffusivity (AD) abnormalities. In addition, the ADHD‐PI group exhibited atypical mean diffusivity in the forceps minor (FMi) and left ATR and AD differences in right CB compared to healthy subjects. Direct comparison between ADHD presentations demonstrated radial diffusivity differences in FMi. WM clusters with FA irregularities in ADHD were associated with neurobehavioral performance across groups. In conclusion, differences in WM microstructure in ADHD presentations strengthen the theory that ADHD‐PI and ADHD‐C are two distinct disorders. Regions with WM irregularity seen in both ADHD presentations might serve as predictors of executive and behavioral functioning across groups. Hum Brain Mapp 37:3323–3336, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
52.
Vermiform appendix torsion is rare, and even more uncommon is the volvulus of appendiceal mucinous tumors. To our knowledge, only nine cases of torsion of the vermiform appendix associated with appendiceal mucinous neoplasms have been reported up to date. We report a case of secondary torsion of the vermiform appendix with mucinous cystadenoma in a 30-year-old man. The symptoms were consistent with acute appendicitis. Diagnostic laparoscopy revealed a mucinous tumor of the appendix with a 360 degrees twisted appendix. In order to avoid peritoneal dissemination open appendectomy was performed. The final pathologic diagnosis was a mucinous cystadenoma of the appendix. The postoperative recovery was uneventful. Secondary torsion of vermiform appendix with mucinous cystadenoma is a rare entity. Correct preoperative diagnosis is unlikely. Open appendectomy is the standard of care for benign mucinous appendiceal tumors. Furthermore, it is important to prevent spillage of the appendiceal mucocele content. 相似文献
53.
Matthew K. Tollefson Stephen A. Boorjian Sara A. Farmer Igor Frank 《World journal of urology》2012,30(6):795-799
Introduction
Pathologic stage is a critically important prognostic factor after radical cystectomy (RC) that is used to guide the use of secondary therapies. However, the risk of disease recurrence, for patients clinically diagnosed with muscle-invasive tumors who are found not to have muscle-invasive disease at RC are poorly defined. Therefore, we reviewed the long-term outcomes in patients who were downstaged to non-invasive urothelial carcinoma at time of RC.Methods
We identified 1,177 consecutive patients with muscle-invasive urothelial carcinoma of the bladder who underwent radical cystectomy at our institution between 1980 and 1999 without neoadjuvant therapy. Postoperative disease recurrence and survival were estimated using the Kaplan?CMeier method and compared using the log rank test. Cox proportional hazard regression models were used to analyze the impact of pathologic stage on survival.Results
Pathologic downstaging to non-muscle invasive disease was identified in 538 (45.7?%) patients. The 10-year cancer-specific survival was 84.1, 77.4, 71.1 and 58.5?% for those with pT0, pTis, pT1 and pT2 tumors, respectively. On multivariate analysis, the risk of cancer-specific mortality was significantly decreased for patients with non-muscle invasive disease than those with organ-confined muscle invasion (RR?0.39; p?=?0.002). There was no difference in disease-specific mortality among patients who had non-invasive (pT0, pTa, or pTis) disease (p?=?0.19).Conclusions
Downstaging from clinical muscle-invasive bladder cancer to non-muscle invasive disease at RC is associated with a significant reduction in cancer-specific mortality. However, even patients with residual non-muscle invasive disease may suffer disease recurrence and require continued surveillance after surgery. 相似文献54.
Pedro Henrique Alves de Morais Vinícius Lacerda Ribeiro Igor Eduardo Caetano de Farias Luiz Eduardo Almeida Silva Fabiana Pirani Carneiro Joel Paulo Russomano Veiga João Batista de Sousa 《World journal of emergency surgery : WJES》2012,7(Z1):S10
Introduction
Most trauma patients are drunk at the time of injury. Up to 2% of traumatized patients develop sepsis, which considerably increases their mortality. Inadequate wound healing of the colonic repair can lead to postoperative complications such as leakage and sepsis.Objective
To assess the effects of acute alcohol intoxication on colonic anastomosis wound healing in septic rats.Methods
Thirty six Wistar rats were allocated into two groups: S (induction of sepsis) and AS (alcohol intake before sepsis induction). A colonic anastomosis was performed in all groups. After 1, 3 or 7 days the animals were killed. Weight variations, mortality rate, histopathology and tensile breaking strength of the colonic anastomosis were evaluated.Results
There was an overall mortality of 4 animals (11.1%), three in the group AS (16.6%) and one in the S group (5.5%). Weight loss occurred in all groups. The colon anastomosis of the AS group didn’t gain strength from the first to the seventh postoperative day. On the histopathological analysis there were no differences in the deposition of collagen or fibroblasts between the groups AS and S.Conclusion
Alcohol intake increased the mortality rate three times in septic animals. Acute alcohol intoxication delays the acquisition of tensile strength of colonic anastomosis in septic rats. Therefore, acute alcohol intoxication before sepsis leads to worse prognosis in animal models of the abdominal trauma patients.55.
Evaluation of myocardial function in patients with end-stage heart failure during support with the Jarvik 2000 left ventricular assist device. 总被引:2,自引:0,他引:2
Markus Ferrari Kamuran A Kadipasaoglu Mihai Croitoru Jeff Conger Tim Myers Igor Gregoric Branislav Radovancevic George V Letsou O H Frazier 《The Journal of heart and lung transplantation》2005,24(2):226-228
In 2 patients with the Jarvik 2000 left ventricular assist device (LVAD), we assessed left ventricular systolic function through pressure-volume loops and E(max) at the beginning and end of the support period to potentially predict the possibility of pump removal without transplantation. Immediately before LVAD implantation and explantation, pressure and volume measurements were made with catheters and echocardiography, respectively, the E(max) being calculated from the slope of the pressure-volume loops, and the left ventricular ejection fraction (LVEF) being estimated by echocardiography. Transplantation was performed after 14 and 62 days, respectively, during which the LVEF increased by 75% (from 12% to 21%) in Patient 1 and remained unchanged (from 16% to 18%) in Patient 2, whereas the E(max) increased from 0.63 and 0.42 mm Hg/ml, respectively, to 1.31 and 1.07 mm Hg/ml, reflecting a 107% and 155% improvement. In these 2 cases, the E(max) was a more reliable indicator of intrinsic myocardial contractility than was the LVEF. 相似文献
56.
Yun TJ Coles JG Konstantinov IE Al-Radi OO Wald RM Guerra V de Oliveira NC Van Arsdell GS Williams WG Smallhorn J Caldarone CA 《The Journal of thoracic and cardiovascular surgery》2005,129(1):167-174
OBJECTIVE: We have previously reported a limited but favorable experience with a novel sutureless technique for surgical management of postoperative pulmonary vein stenosis occurring after repair of total anomalous pulmonary venous drainage. Because this technique requires integrity of the retrocardiac space for hemostasis, extension of the technique to the primary repair of pulmonary vein anomalies requires evaluation. This analysis reviews our experience with the sutureless technique in patients with postrepair pulmonary vein stenosis, as well as our extension of the technique into primary repair of pulmonary vein anomalies. METHODS: Retrospective univariable-multivariable analysis of all pulmonary vein stenosis procedures and sutureless pulmonary vein procedures over a 20-year period was performed. Cox proportional hazards modeling was used to identify variables associated with freedom from reoperation or death. RESULTS: Sixty patients underwent 73 procedures, with pulmonary vein stenosis present in 65 procedures. The sutureless technique was used in 40 procedures. Freedom from reoperation or death at 5 years after the initial procedure was 49%. Unadjusted freedom from reoperation or death was greater with the sutureless technique for patients with postrepair pulmonary vein stenosis ( P = .04). By using multivariable analysis, a higher pulmonary vein stenosis score was associated with greater risk of reoperation or death. After adjustment, the sutureless repair was associated with a nonsignificant trend toward greater freedom from reoperation or death ( P = .12). Despite the absence of retrocardiac adhesions, operative mortality was not increased with the sutureless technique ( P = .64). Techniques to control bleeding (intrapleural hilar reapproximation) and improve exposure (inferior vena cava division) were identified. CONCLUSION: The sutureless technique for postrepair pulmonary vein stenosis is associated with encouraging midterm results. Extension of the indications for the technique to primary repair appears safe with the development of simple intraoperative maneuvers. 相似文献
57.
Frank I Blute ML Leibovich BC Cheville JC Lohse CM Kwon ED Zincke H 《The Journal of urology》2005,173(2):380-384
PURPOSE: The 2002 tumor classification for renal cell carcinoma (RCC) classifies pT2 tumors as more than 7 cm in greatest dimension, limited to the kidney. In this study we determined whether a size cutoff point exists within pT2 tumors and whether such subclassification would further improve the accuracy of the current tumor classification. MATERIALS AND METHODS: We studied 544 patients with unilateral, sporadic pT2 RCC treated with radical nephrectomy or nephron sparing surgery between 1970 and 2000. The association of tumor size with death from RCC was examined using martingale residuals from a Cox proportional hazards regression model to determine the optimal size cutoff point. RESULTS: There were 204 deaths from RCC a median of 3.8 years following nephrectomy. Univariately tumor size was significantly associated with death from RCC (risk ratio 1.08, 95% CI 1.04 to 1.13, p <0.001). A scatterplot of tumor size vs expected risk of death per patient suggested that a cutoff point between 9 and 10 cm was appropriate. When adjusted for regional lymph node involvement and distant metastases, the 10 cm cutoff point performed better than the 9 cm point (risk ratio 1.42, 95% CI 1.07 to 1.90, p = 0.017 vs 1.22, 95% 0.86 to 1.72, p = 0.268). Therefore, we propose using a 10 cm cutoff point to subclassify patients into pT2a and pT2b. CONCLUSIONS: Our data suggest that the prognostic accuracy of the 2002 pT2 tumor classification can be further improved by subclassifying patients with tumors greater than 7 and less than 10 cm into a pT2a category, and those with tumors 10 cm or greater into a pT2b category. 相似文献
58.
Houweling AR Bazhenov M Timofeev I Steriade M Sejnowski TJ 《Cerebral cortex (New York, N.Y. : 1991)》2005,15(6):834-845
Chronically isolated neocortex develops chronic hyperexcitability and focal epileptogenesis in a period of days to weeks. The mechanisms operating in this model of post-traumatic epileptogenesis are not well understood. We hypothesized that the spontaneous burst discharges recorded in chronically isolated neocortex result from homeostatic plasticity (a mechanism generally assumed to stabilize neuronal activity) induced by low neuronal activity after deafferentation. To test this hypothesis we constructed computer models of neocortex incorporating a biologically based homeostatic plasticity rule that operates to maintain firing rates. After deafferentation, homeostatic upregulation of excitatory synapses on pyramidal cells, either with or without concurrent downregulation of inhibitory synapses or upregulation of intrinsic excitability, initiated slowly repeating burst discharges that closely resembled the epileptiform burst discharges recorded in chronically isolated neocortex. These burst discharges lasted a few hundred ms, propagated at 1-3 cm/s and consisted of large (10-15 mV) intracellular depolarizations topped by a small number of action potentials. Our results support a role for homeostatic synaptic plasticity as a novel mechanism of post-traumatic epileptogenesis. 相似文献
59.
Madersbacher S Lackner J Brössner C Röhlich M Stancik I Willinger M Schatzl G;Prostate Study Group of the Austrian Society of Urology 《European urology》2005,47(4):499-504
OBJECTIVE: To analyse long-term rates of reoperation, myocardial infarction and mortality after transurethral (TURP) and open prostatectomy (open PE) in a nation-wide analysis. MATERIAL AND METHODS: Patients who underwent TURP (n=20,671) or open PE (n=2452) in Austria between 1992 and 1996 entered this study and were followed for up to 8 years. Actuarial cumulative incidences of reoperation (TURP, urethrotomy, bladder neck incision), myocardial infarction and death after 1, 5 and 8 years were calculated. Data were provided by the Austrian Health Institute (OBIG). RESULTS: Actuarial cumulative incidences of a secondary TURP after primary TURP at 1, 5 and 8 years were 2.9%, 5.8% and 7.4%; the respective numbers after open PE 1.0%, 2.7% and 3.4%. The overall incidence of a secondary endourological procedure (TURP, urethrotomy, bladder neck incision) within 8 years was 14.7% after TURP and 9.5% after open PE. The 8 years incidence of myocardial infarction was identical after TURP (4.8%) and open PE (4.9%). In parallel, mortality rates at 90 days (TURP: 0.7%; open PE: 0.9%), one year (2.8% vs. 2.7%), 5 years (12.7% vs. 11.8%) and 8 years (20% vs. 20.9%) was identical after TURP and open PE. CONCLUSIONS: This large-scale, contemporary, nation-wide analysis confirms the higher reoperation rate after TURP compared to open PE. We observed no excess risk of myocardial infarction or death after TURP compared to open PE. 相似文献
60.
The survival benefit of kidney transplantation in the setting of combined peripheral arterial disease and end‐stage renal failure 下载免费PDF全文
Given the deleterious effects of concomitant peripheral arterial disease (PAD) and severe renal disease, a role for aggressive screening and management of PAD in renal failure patients has been suggested. However, limited data exist detailing the impact of PAD on kidney waitlist survival and the potential benefit of transplantation in PAD. Multivariable COX regression and Kaplan–Meier survival models were fit using UNOS data to assess kidney waitlist and post‐transplant five‐yr survival. Compared to PAD?Dial? (no PAD or dialysis) waitlist survival, PAD+Dial? was associated with a 36%, PAD?Dial+ a 95%, and PAD+Dial+ a 190% increased risk of death. A significant survival benefit of kidney transplantation was identified in the PAD population (p < 0.001, HR = 0.440 comparing post‐transplant to waitlist survival). Time to survival benefit (equal mortality between waitlist and post‐transplant population) of kidney transplantation in PAD+ was realized 2.5 times sooner in pre‐emptive transplantation than transplant after dialysis (154 d vs. 381 d), per unadjusted Kaplan–Meier analysis. To our knowledge, this is the first study to demonstrate a survival benefit of kidney transplantation in the setting of PAD. Pre‐emptive transplantation with emphasis on living donation prior to dialysis should be advocated to improve outcomes in this high risk patient population. 相似文献