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121.
Cirrhosis with ascites is associated with impaired renal function accompanied by sodium and water retention. Although it has been suggested that mediators such as nitric oxide play a role in the development of renal failure in this situation, other mechanisms underlying the process are not well understood. This study examined the role of oxidative stress in mediating renal damage during the development of cirrhosis in order to understand mechanisms involved in the process. It was shown that carbon tetrachloride- or thioacetamide-induced cirrhosis in rats results in oxidative stress in the kidney as seen by increased lipid peroxidation and protein oxidation, accompanied by altered antioxidant status. Cirrhosis was also found to affect renal mitochondrial function, as assessed by measurement of the respiratory control ratio, the swelling of mitochondria, and calcium flux across mitochondrial membranes. Increased lipid peroxidation and changes in lipid composition were evident in the renal brush border membranes, with compromised transport of 14C glucose across these membranes. In conclusion, renal alterations produced as a result of cirrhosis in the rat are possibly mediated by oxidative stress.  相似文献   
122.
Mathew NT  Kailasam J  Meadors L 《Headache》2008,48(3):442-447
OBJECTIVE: We assessed the efficacy and safety of botulinum toxin type A (BoNTA; BOTOX): Allergan, Inc., Irvine, CA, USA) in patients with nummular headache who did not respond to other treatments including nonsteroidal anti-inflammatory drugs (NSAIDs), local anesthetics, and/or gabapentin. BACKGROUND: Nummular headache is characterized by circumscribed round or elliptical areas of fluctuating mild-to-moderate head pain in a chronic or remitting pattern. It is a relatively rare primary headache disorder that responds poorly to adequate treatment trials with local anesthetic, migraine, or neuropathic pain agents or NSAIDs. METHODS: Four patients aged 35-58 years with intractable nummular headaches were given 25 units of BoNTA divided among 10 injection sites in and around the circumscribed affected areas of pain, paresthesia, and allodynia. All patients had 2 sets of injections approximately 14 weeks apart. RESULTS: All patients met the International Headache Society criteria for nummular headache (International Classification of Headache Disorders, A13.7.1). Patients were female; mean age of onset was 42 years. Average disease duration prior to BoNTA treatment was 3.75 years. One patient reported concurrent episodic migraine and another reported concurrent tension-type headache. Patients reported round-shaped (n = 2; 6 and 3 cm in diameter), oval (n = 1; 4 x 2 cm), and elliptical (n = 1; 6 cm in length) areas of pain. Painful symptoms were reported in the right parietal convexity (n = 2) and the posterior frontal, unilaterally (n = 2). All patients experienced spontaneous or stimuli-triggered exacerbations and variable combinations of sensory disturbances, including allodynia, tenderness, and paresthesia. The temporal pattern was continuous in 3 patients and intermittent in one. Both the size and shape of the pain remained unchanged in all patients since the onset of nummular headache symptoms. Six to 10 days following BoNTA treatment, all patients experienced a reduction in nummular headache symptoms, which lasted approximately 14 weeks on average. Repeat injections gave the same degree of improvement. No treatment-related adverse events were reported. CONCLUSIONS: BoNTA appears to be a well-tolerated effective treatment for intractable, persistent nummular headache in patients with an inadequate response to other treatments including NSAIDs, gabapentin, or local anesthetics.  相似文献   
123.
Mathew NT  Kailasam J  Meadors L 《Headache》2008,48(2):194-200
OBJECTIVE: To evaluate predictors of response to botulinum toxin type A (BoNTA; BOTOX, Allergan Inc., Irvine, CA, USA) in patients with chronic daily headache (CDH). BACKGROUND: Chronic migraine (CM) and chronic tension-type headache (CTTH) form the majority of CDH disorders. Controlled trials indicate that BoNTAis effective in reducing the frequency of headache and number of headache days in patients with CDH disorders. A recent migraine study found that patients with imploding or ocular types of headaches were responders to BoNTA, whereas those with exploding headaches were not. To date, there are no data on factors that might predict response to BoNTA in patients with CDH. METHODS: A total of 71 patients with CM and 11 patients with CTTH were treated with 100 units BoNTA. Every patient received at least 2 sets of injections at intervals of 12-15 weeks; fixed sites, fixed dose, and "follow-the-pain" approaches were used for the injections. A detailed medical history was taken for each patient in addition to recording Migraine Disability Assessment Scale (MIDAS) scores at baseline and every 3 months after each set of injections. Headache frequency was assessed throughout the study from baseline to weeks 24-27. Patients recorded the frequency, severity, and duration of headaches in Headache Diaries. Patients were divided into responders (> or = 50% reduction in both headache frequency and MIDAS scores compared with baseline) and nonresponders (< 50% reduction in either of the above variables). Variables analyzed for predictors of response include headache that is predominantly unilateral or bilateral in location, presence of cutaneous allodynia (scalp allodynia), and presence of pericranial muscle tenderness (also referred to as muscle allodynia). Chi-square analysis was used for parallel-group comparisons (proportion of CM responders vs proportion of CM nonresponders and proportion of CTTH responders vs proportion of CTTH nonresponders). RESULTS: In the CM group, 76.1% (54 /71) of patients were responders to BoNTA, of which 68.5% (37/54) had headache that was predominantly unilateral in location and the remaining 31.5% (17/54) had headache that was predominantly bilateral in location (both P < .01 vs CM nonresponders). Of the 23.9% (17/71) CM nonresponders, 76.5% (13/17) reported predominantly bilateral headache and in the remaining 23.5% (4/17) the headache was unilateral. In the CM responders group, 81.5% (44/54) had clinically detectable scalp allodynia, while pericranial muscle tenderness was present in 61.1% (33/54) (both P < .01 vs CM nonresponders). The presence of scalp allodynia and pericranial muscle tenderness in the CM nonresponders was 11.8% (2/17) and 17.6% (3/17), respectively. In the CTTH group where all patients (100%, 11/11) had bilateral headache, 36.4% (4/11) of patients were responders to BoNTA. All of those CTTH responders (100%, 4/4) had pericranial muscle tenderness (P < .05 vs CTTH nonresponders). None of the CTTH nonresponders had pericranial muscle tenderness. No clinically significant serious adverse events (AEs) were reported. Mild AEs, eg, injection-site pain that persisted for 1-9 days, were reported in 11 patients. One patient had transient brow ptosis. CONCLUSIONS: A greater percentage of patients with CM responded to BoNTA than patients with CTTH. Headaches that were predominantly unilateral in location, presence of scalp allodynia, and pericranial muscle tenderness appear to be predictors of response to BoNTA in CM, whereas in CTTH, pericranial muscle tenderness may be a predictor of response.  相似文献   
124.
125.
Background: One of the strategies of the Revised National Tuberculosis Control Programme in India to achieve tuberculosis control is by increasing case detection through a nationwide network of designated microscopy centres (DMC). Practice of standard precautions for infection control in these DMCs is very important to prevent transmission of infection not only to the laboratory personnel, but also to the general population. However, in India this has not been evaluated by an external agency.Method: A cross-sectional study was carried out to assess knowledge, facilities and compliance regarding infection control practices (ICP) in all 38 DMCs in Kannur district, Kerala, India, in 2015. Using observations and interviews, the investigators collected data in a structured format.Results: Overall knowledge about infection control was found to be satisfactory among 29% of laboratory technicians. Overall facilities for infection control were satisfactory in 61% of the DMCs, while adherence to ICP was satisfactory in 45% of the DMCs. Knowledge regarding ICP was better in government DMCs, whereas facilities for ICP and adherence to biomedical waste management guidelines were better in private DMCs.Conclusion: Given the higher risk of infection among laboratory technicians, there is an urgent need to address the shortcomings in infection control practices.  相似文献   
126.
127.
Cirrhosis is associated with altered gastrointestinal function, and bacterial translocation from the gut plays an important role in the etiology of spontaneous bacterial peritonitis (SBP) seen in this condition. Although alterations in gut motility and intestinal permeability are recognized in cirrhosis, the intestinal damage at the cellular and subcellular levels is not well understood. This study looked at the mucosal alterations in experimental cirrhosis and the role of oxygen free radicals in this process. It was shown that cirrhosis results in oxidative stress in the intestine, as seen by increased xanthine oxidase (XO) activity and altered antioxidant status. Cirrhosis also affects enterocyte mitochondrial function, as assessed by respiratory control ratio, swelling, and calcium flux. Increased lipid peroxidation of the brush border membranes (BBMs) was seen along with altered intestinal transport. In conclusion, this study shows that intestinal mucosal alterations are seen in experimental cirrhosis and are possibly mediated by oxidative stress.  相似文献   
128.

Background

Intraductal papillary mucinous neoplasms (IPMNs) are radiographically identifiable potential precursor lesions of pancreatic adenocarcinoma. While resection is recommended when main duct dilation is present, management of branch duct IPMN (BD-IPMN) remains controversial. This study sought to evaluate whether preoperative quantitative imaging features of BD-IPMNs could distinguish low-risk disease (low- and intermediate-grade dysplasia) from high-risk disease (high-grade dysplasia and invasive carcinoma).

Methods

Patients who underwent resection between 2005 and 2015 with pathologically proven BD-IPMN and a preoperative CT scan were included in the study. Quantitative image features were extracted using texture analysis and a novel quantitative mural nodularity feature developed for the study. Significant features on univariate analysis were combined with clinical variables to build a multivariate prediction model.

Results

Within the study group of 103 patients, 76 (74%) had low-risk disease and 27 (26%) had high-risk disease. Quantitative imaging features were prognostic of low-vs. high-risk disease. The model based only on clinical variables achieved an AUC of 0.67 and 0.79 with the addition of quantitative imaging features.

Conclusion

Quantitative image analysis of BD-IPMNs is a novel method that may enable risk stratification. External validation may provide a reliable non-invasive prognostic tool for clinicians.  相似文献   
129.

Purpose

In the medical field, radiologists need more informative and high-quality medical images to diagnose diseases. Image fusion plays a vital role in the field of biomedical image analysis. It aims to integrate the complementary information from multimodal images, producing a new composite image which is expected to be more informative for visual perception than any of the individual input images. The main objective of this paper is to improve the information, to preserve the edges and to enhance the quality of the fused image using cascaded principal component analysis (PCA) and shift invariant wavelet transforms.

Methods

A novel image fusion technique based on cascaded PCA and shift invariant wavelet transforms is proposed in this paper. PCA in spatial domain extracts relevant information from the large dataset based on eigenvalue decomposition, and the wavelet transform operating in the complex domain with shift invariant properties brings out more directional and phase details of the image. The significance of maximum fusion rule applied in dual-tree complex wavelet transform domain enhances the average information and morphological details.

Results

The input images of the human brain of two different modalities (MRI and CT) are collected from whole brain atlas data distributed by Harvard University. Both MRI and CT images are fused using cascaded PCA and shift invariant wavelet transform method. The proposed method is evaluated based on three main key factors, namely structure preservation, edge preservation, contrast preservation. The experimental results and comparison with other existing fusion methods show the superior performance of the proposed image fusion framework in terms of visual and quantitative evaluations.

Conclusion

In this paper, a complex wavelet-based image fusion has been discussed. The experimental results demonstrate that the proposed method enhances the directional features as well as fine edge details. Also, it reduces the redundant details, artifacts, distortions.
  相似文献   
130.
The study assesses the role of Medicare Advantage (MA) plans in providing quality primary care in comparison to FFS Medicare in three states, New York, California, Florida, across three racial ethnic groups. The performance is measured in terms of providing better quality primary care, as defined by lowering the risks of preventable hospital admissions. Using 2004 hospital discharge data (HCUP-SID) of Agency for Healthcare Research and Quality for three states, a multivariate cross sectional design is used with individual admission as the unit of analysis. The study found that MA plans were associated with lower preventable hospitalizations relative to marker admissions. The benefit also spilled over to different racial and ethnic subgroups and in some states, e.g. CA and FL, MA enrollment was associated with significantly lower odds of minority admissions than of white admissions. These results may indicate a potentially favorable role of MA plans in attenuating racial/ethnic inequalities in primary care in some states.  相似文献   
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