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Purpose: To evaluate changes in distribution of hepatic arterial blood flow in the liver following insertion of an uncovered stent and subsequently a stent-graft in the transjugular intrahepatic portosystemic shunt (TIPS) channel. Methods: The experiments were performed in eight healthy pigs under general anesthesia. In a pilot study in one pig, scintigraphic evaluation of arterial perfusion to the liver was done before and after inflation of a balloon in the right hepatic vein. In the other pigs, outflow from the right liver vein was checked repeatedly by contrast injection through a percutaneously inserted catheter. The arterial perfusion through the liver was examined by scintigraphy, following selective injection of macro-aggregate of 99Tc m-labeled human serum albumin 99Tc m-HSA) into the hepatic artery. This examination was done before and after creation of a TIPS with an uncovered stent and subsequently after insertion of a covered stent-graft into the cranial portion of the shunt channel. Results: In the pilot study changes in the arterial perfusion to the liver were easily detectable by scintigraphy. One pig died during the procedure and another pig was excluded due to dislodgement of the hepatic artery catheter. The inserted covered stent obstructed venous outflow from part of the right liver lobe. The 99Tc m-HSA activity in this part remained unchanged after TIPS creation with an uncovered stent. A reduction in activity was seen after insertion of a stent-graft (p= 0.06). Conclusion: The distribution of the hepatic arterial blood flow is affected by creation of a TIPS with a stent-graft, in the experimental pig model.  相似文献   
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Purpose

The aim of this pilot study was to describe the hydration and nutritional status of a cohort of elderly dialysis patients and to explore the association between these parameters and the quality of life (QoL).

Methods

All patients over 75?years of age being in chronic dialysis by January 2008 at 3 dialysis units (n?=?34) were asked to participate in this pilot study, 24 patients were entered. Hydration status was assessed by bioimpedance spectroscopy (BIS) and nutritional status by the subjective global assessment (SGA), BIS, anthropometric measures and biochemical parameters. Based on these assessments the patients were classified as being cachectic or not according to newly defined criteria. QoL was measured using the SF-36.

Results

The results showed cachexia in 6 (25?%), 37.5?% had a body mass index below 24, whereas according to SGA 91?% were malnourished. BIS showed low lean tissue index in 46?% and overhydration in 35?% of the patients. Compared to non-cachectic and normohydrated, cachectic and overhydrated patients reported consistently poorer QoL. For cachectic patients, the differences were clinically significant for all SF-36. BIS was easily applicable when used before dialysis.

Conclusions

The high frequency of nutritional deficits in this study calls for more attention to nutritional status in elderly dialysis patients. There is a need for a general agreement on how nutritional status should be assessed and reported, both in clinics and in research.  相似文献   
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War experiences may have an extensive impact on the health status of the exposed populations. This population‐based study aimed to examine the relationship between war experiences and self‐reported general health in representative sample surveys from Bosnia‐Herzegovina (n = 3,313) and Kosovo (n = 1,000). Data were collected with face‐to‐face interviews fielded in the winter of 2003–2004. Logistic regression analysis was used to compute unadjusted and adjusted odds ratios (ORs). The adjusted effects of the extensiveness of war experiences on poor health were positive in both countries, but they were statistically significant only for Bosnia‐Herzegovina: OR = 1.04, 95% CI [1.00, 1.08] for Bosnia‐Herzegovina and OR = 1.03, 95% CI [0.98, 1.09] for Kosovo. The strongest observed effect was found for Kosovo only: The extensiveness of war experiences was relatively strongly related to longstanding health problems, OR = 1.09, 95% CI [1.03, 1.15]. We found that war experiences may contribute to increased poorer health in the exposed populations; however, the effects 4–9 years after the war ended were modest. Hence, war experiences seemed to be more strongly related to war‐related distress and posttraumatic stress disorder than to self‐reported general health.  相似文献   
18.
Background: Neuropathic pain in spinal cord injury is a common challenging therapeutic condition. The current study examines the analgesic effect of the sodium channel blocker lidocaine on neuropathic pain in patients with spinal cord injury and the predictive role of concomitant evoked pain on pain relief with lidocaine.

Methods: Twenty-four spinal cord injury patients with neuropathic pain at or below the level of injury were randomized and completed a double-blind crossover trial of 5 mg/kg lidocaine and placebo infused over 30 min. Twelve patients reported evoked pain, and 12 patients had no evoked pain. Spontaneous and evoked pains were assessed using a visual analog scale and quantitative sensory testing.

Results: Lidocaine significantly reduced spontaneous pain in all patients (P < 0.01) and in each of the two groups with (P < 0.01) and without (P = 0.048) evoked pain, with no difference in number of responders (pain reduction >= 33%) between the patients with (n = 6) and without (n = 5) evoked pain. Lidocaine significantly relieved both at-level and below-level neuropathic pain and decreased brush-evoked dysesthesia but not cold allodynia, pinprick hyperalgesia, or pain evoked by repetitive pinprick.  相似文献   

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The integrin alpha v beta3 receptor is upregulated on tumor cells and endothelium and plays important roles in angiogenesis and metastasis. Arg-Gly-Asp (RGD) peptide ligands have high affinity for these integrins and can be radiolabeled for PET imaging of angiogenesis or tumor development. We have assessed the safety, stability, and tumor distribution kinetics of a novel radiolabeled RGD-based integrin peptide-polymer conjugate, 18F-AH111585, and its feasibility to detect tumors in metastatic breast cancer patients using PET. METHODS: The biodistribution of 18F-AH111585 was assessed in 18 tumor lesions from 7 patients with metastatic breast cancer by PET, and the PET data were compared with CT results. The metabolic stability of 18F-AH111585 was assessed by chromatography of plasma samples. Regions of interest (ROIs) defined over tumor and normal tissues of the PET images were used to determine the kinetics of radioligand binding in tissues. RESULTS: The radiopharmaceutical and PET procedures were well tolerated in all patients. All 18 tumors detected by CT were visible on the 18F-AH111585 PET images, either as distinct increases in uptake compared with the surrounding normal tissue or, in the case of liver metastases, as regions of deficit uptake because of the high background activity in normal liver tissue. 18F-AH111585 was either homogeneously distributed in the tumors or appeared within the tumor rim, consistent with the pattern of viable peripheral tumor and central necrosis often seen in association with angiogenesis. Increased uptake compared with background (P = 0.002) was demonstrated in metastases in lung, pleura, bone, lymph node, and primary tumor. CONCLUSION: 18F-AH111585 designed to bind the alpha v beta3 integrin is safe, metabolically stable, and retained in tumor tissues and detects breast cancer lesions by PET in most anatomic sites.  相似文献   
20.
Implant-related research is particularly prone to produce biased results. Despite a common commitment to evidence-based principles (EBM) principles in current literature, a gap remains between the existing available evidence and its actual implementation in orthopaedic clinical practice. Knowledge of basic principles of implant related trial design is a prerequisite for critical appraisal of the value of scientific evidence and thereby the degree of uncertainty. This article discusses how the quality of implant-related randomized controlled trials (RCT) can be affected by the level of expertise, the choice of outcome measures, the allocation procedure, and the method of blinding. Taking these issues into consideration in the design of an implant-related study improves the value of the study, thereby achieving an unbiased assessment of the safety and efficacy of an innovative implant prior to its widespread implementation in daily health care.  相似文献   
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