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Early life experience differentially shapes later stress reactivity, as evidenced by both animal and human studies. However, early experience-related changes in the function of central visceral neural circuits that control stress responses have not been well characterized, particularly in humans. The paraventricular nucleus of the hypothalamus (PVN), bed nucleus of the stria terminalis (BNST), amygdala (Amyg) and subgenual anterior cingulate cortex (sgACC) form a core visceral stress-responsive circuit. The goal of this study is to examine how childhood emotional and physical abuse relates to adulthood stressor-evoked activity within these visceral brain regions. To evoke acute states of mental stress, participants (n = 155) performed functional magnetic resonance imaging (fMRI)-adapted versions of the multi-source interference task (MSIT) and the Stroop task with simultaneous monitoring of mean arterial pressure (MAP) and heart rate. Regression analyses revealed that childhood physical abuse correlated positively with stressor-evoked changes in MAP, and negatively with unbiased, a priori extractions of fMRI blood-oxygen level-dependent signal change values within the sgACC, BNST, PVN and Amyg (n = 138). Abuse-related changes in the function of visceral neural circuits may reflect neurobiological vulnerability to adverse health outcomes conferred by early adversity.  相似文献   
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With good hemostatic ability, the end-firing continuous-wave diode laser at 980 nm was used to enucleate the prostate (DiLEP) for the treatment of benign prostatic obstruction (BPO). The study compared the patients' demographics and surgical outcomes between DiLEP and transurethral resection of the prostate (TURP). Patients with significant BPO and a total prostatic weight of 40 g or more who had undergone DiLEP (n = 74) or TURP (n = 52) during the same period at our hospital were enrolled for analysis. DiLEP was performed by a single surgeon (Yang), and TURP by three surgeons (Yang, Hsieh and Chang). The 4-U incision technique was developed for DiLEP. The diode laser ensured bloodless incision followed by blunt dissection using the resectoscope and laser fiber as an 'index finger' to enucleate the prostate. To prevent unexpected deep thermal damage, the power of the laser was set at 80 W and the laser beam was directed towards the bladder neck and not towards the prostatic capsule. Demographic data and perioperative parameters were comparable between the two groups, except that DiLEP resulted in a significantly lower drop in hemoglobin level (0.9 ± 1.0 vs. 1.6 ± 2.4 g/dl, p = 0.03), shorter catheterization time (41.2 ± 19.9 vs. 67.7 ± 33.3 h, p = 0.01), and shorter postoperative stay (2.9 ± 1.9 vs. 4.1 ± 6.2 days, p = 00.01). Delayed postoperative sloughing of necrotic tissue was not observed in the DiLEP group. Improvements in voiding parameters were comparable between the groups, and were sustained during a follow-up of up to 1 year. DiLEP provided better hemostasis than TURP as evidenced by less blood loss. The role of DiLEP treating BPO requires further investigation.  相似文献   
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Update on uveomeningoencephalitides   总被引:1,自引:0,他引:1  
PURPOSE OF REVIEW: Uveomeningoencephalitides, commonly known as Vogt-Koyanagi-Harada (VKH) disease, are characterized by chronic bilateral granulomatous panuveitis involving the central nervous, auditory and integumentary systems. Visual prognosis is generally favourable, but outcomes in patients with VKH disease may vary. Also, the treatment of choice differs in different parts of the world. This review addresses the literature on the possible pathogenesis, diagnosis and treatment of this disorder. RECENT FINDINGS: Atypical presentations of VKH disease, as well as those associated with interferon-alpha therapy, have been reported. Most reports suggest an association with autoimmunity. The diagnostic criteria were revised by the International Workshop on VKH in 1999, allowing for the presence of different ocular findings in the early and late stages of the disease. New techniques have also been developed to aid in the rapid diagnosis of VKH disease and evaluation of treatment. Different routes of administration of corticosteroid and adjuvant therapy were tried, with positive results. SUMMARY: Although the pathogenesis of VKH disease is uncertain and antigen-specific treatment strategies have not yet been developed, reports increasingly suggest an autoimmune nature for uveomeningoencephalitides. Currently, systemic corticosteroid therapy remains the standard initial treatment. Different routes of administration are used to reduce the frequency of side effects of systemic corticosteroids, and there are various adjuvant therapies. With the aid of modern equipment, early diagnosis and prompt and appropriate treatment, resulting in better visual outcomes, can be anticipated. A large-scale, multinational, prospective study is warranted to determine the optimal initial therapy.  相似文献   
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We describe a computer application, "BioVision", that can be trained to quickly and effectively classify and quantify user definable histological objects (e.g., senile plaques, neurofibrillary tangles) within single or double-labeled immunocytochemically stained sections. For a given image population, BioVision is interactively trained (in Independent User Mode) by an investigator to perform the desired classifications. This training yields a statistical model of the different types of objects occurring in the target image population. The resulting model can then be used (in Automated User Mode) to classify all objects in any image or images from the target population. BioVision simplifies the quantification of complex visual objects and improves inter-rater reliability. The program accomplishes classification in two major stages: pixel classification and blob classification. In pixel classification, each pixel is assigned to one of some number of substance classes, based on its chromatic properties and local context, reflecting basic histological distinctions of interest. In the blob classification phase, the image's pixels are first partitioned into "blobs": maximal connected sets of pixels assigned to the same substance class. Then, based on its size, shape, textural and contextual properties, each blob is assigned to a histological object class. A Bayesian classifier is used in each of the pixel and blob classification stages. We report several tests of BioVision. First, we applied BioVision to classify senile plaques and neurofibrillary tangles in several test cases of Alzheimer's brain immunostained for beta-amyloid and PHF-tau and compared the results to those produced by experienced investigators. BioVision was trained to classify Plaque-type blobs as either plaques or plaque-type nonentities, and tangle-type blobs as either tangles or tangle-type nonentities. BioVision classified the objects with an accuracy comparable to the trained investigator. Next, we applied BioVision to the task of counting all the tangles in hippocampal images from 22 Alzheimer's disease (AD) cases selected to span a broad range of dementia levels from the tissue repository of UC Irvine's Center for the study of Brain Aging and Dementia. The tangle counts produced by BioVision proved to be significantly better predictors of the cases' adjusted MMSE scores than any of tangle load, age at death, post mortem interval or the interval between the last MMSE score and death.  相似文献   
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