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11.
Evidence has been obtained that catecholamines and their metabolites are present in single lymphocytes and extracts of T- and B-cell clones by use of capillary electrophoresis with electrochemical detection. Pharmacological inhibition of tyrosine hydroxylase reduces observed catecholamine levels, suggesting catecholamine synthesis by lymphocytes. Intracellular dopamine levels are shown to be increased by extra-cellular dopamine, suggesting a cellular-uptake mechanism. Furthermore, incubation with either dopamine or L-dihydroxyphenylalanine, a precursor of dopamine, results in a dose-dependent inhibition of lymphocyte proliferation and differentiation. Together, these results suggest the presence of an autocrine loop whereby lymphocytes down-regulate their own activity.  相似文献   
12.
The presentation of the World Health Organization (WHO)’s roadmap for neglected tropical diseases (NTDs) in January 2012 raised optimism that many NTDs can indeed be eliminated. To make this happen, the endemic, often low-income countries with still heavy NTD burdens must substantially strengthen their health systems. In particular, they need not only to apply validated, highly sensitive diagnostic tools and sustainable effective control approaches for treatment and transmission control, but also to participate in the development and use of surveillance–response schemes to ensure that progress made also is consolidated and sustained. Surveillance followed-up by public health actions consisting of response packages tailored to interruption of transmission in different settings will help to effectively achieve the disease control/elimination goals by 2020, as anticipated by the WHO roadmap. Risk-mapping geared at detection of transmission hotspots by means of geospatial and other dynamic approaches facilitates decision-making at the technical as well as the political level. Surveillance should thus be conceived and developed as an intervention approach and at the same time function as an early warning system for the potential re-emergence of endemic infections as well as for new, rapidly spread epidemics and pandemics.  相似文献   
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BACKGROUND/AIMS: Gallbladder abnormalities may be part of the spectrum in primary sclerosing cholangitis (PSC). The aim of the present study was to evaluate the occurrence and prognostic importance of gallbladder abnormalities in patients with PSC. METHODS: Presence of gallbladder abnormalities was assessed in 286 patients with PSC treated at the Liver Unit, Karolinska University Hospital, Huddinge, between 1970 and 2005. RESULTS: One or more gallbladder abnormalities were found in 41% of the patients. Gallstones were found in 25% and cholecystitis in 25%. Cholecystitis among patients with extrahepatic involvement of PSC (30% (65/214)) was significantly higher than among those with intrahepatic involvement (9% (6/70)) (P<0.0001). A gallbladder mass lesion with a mean size of 21 (+/-9) mm (S.D.) was found in 18 (6%) patients, in 56% (10/18) of whom it constituted gallbladder carcinoma. In 9 patients without a gallbladder mass lesion, histological re-evaluation disclosed epithelial dysplasia of the gallbladder. CONCLUSIONS: Gallbladder disease is common in patients with PSC. Dysplasia and carcinoma are commonly found in gallbladder epithelium, suggesting that regular examination of the gallbladder in PSC patients could be of value for early detection of a gallbladder mass lesion. Cholecystectomy is recommended when such a lesion is detected, regardless of its size.  相似文献   
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Introduction

In recent years there have been increasing evidence associating liver disease with hypercoagulability, rather than bleeding. The aim of the study was to evaluate the haemostatic potential in patients with liver disease.

Patients and methods

We measured thrombin generation in the presence and absence of thrombomodulin in patients with portal vein thrombosis (PVT, n = 47), Budd-Chiari syndrome (BCS, n = 15) and cirrhosis (n = 24) and compared the results to those obtained from healthy controls (n = 21). Fifteen patients with PVT and 10 patients with BCS were treated with warfarin and were compared to an equal number of patients with atrial fibrillation matched for prothrombin time-international normalized ratio. We assessed resistance to thrombomodulin by using ratios [marker measured in the presence/absence of thrombomodulin].

Results

There were no differences in thrombin generation between patients on warfarin treatment and their controls. Cirrhotic patients generated more thrombin in the presence of thrombomodulin and exhibited thrombomodulin resistance compared to controls [p = 0.006 for endogenous thrombin potential (ETP) and p < 0.001 for peak thrombin and both ratios ETP and peak] and patients with non-cirrhotic PVT (p = 0.001, p = 0.006, p < 0.001, p < 0.001 for ETP, peak, ratio ETP, ratio peak, respectively). The patients with cirrhotic PVT exhibited higher ETP (p = 0.044) and peak (p = 0.02) in the presence of thrombomodulin than controls, as well as thrombomodulin resistance (ETP and peak ratios: p = 0.001).

Conclusions

Hypercoagulability and thrombomodulin resistance in patients with cirrhosis were independent of the presence of splanchnic vein thrombosis. The hypercoagulability in patients with cirrhotic PVT could have implications for considering longer or more intensive treatment with anticoagulants in this group.  相似文献   
17.
Abstract Objective. Several studies have implicated primary sclerosing cholangitis (PSC) as an additional risk factor for colorectal neoplasia in inflammatory bowel disease (IBD). Some reports have indicated that the risk is even higher in PSC-IBD patients after liver transplantation (Ltx), but this issue is controversial. We aimed to compare the risk of colorectal neoplasia in PSC-IBD patients before and after Ltx and to identify risk factors for colorectal neoplasia post-transplant. Material and methods. In a multicenter study within the Nordic Liver Transplant Group, we assessed the risk of colorectal neoplasia by using the competing risk regression analysis. Results. Among the 439 PSC patients included, 353 (80%) had IBD at the time of Ltx and 15 (3%) patients developed de novo IBD post-Ltx. The median duration of IBD was 15 (0-50) years at the time of Ltx and follow-up after Ltx was 5 (0-20) years. Ninety-one (25%) PSC-IBD patients developed colorectal neoplasia. The cumulative risk of colorectal neoplasia was higher after than before Ltx (HR: 1.9, 95% CI: 1.3-2.9, p = 0.002). A multivariate analysis demonstrated aminosalicylates and ursodeoxycholic acid as significantly associated with an increased risk of colorectal neoplasia post-Ltx. Duration and activity of IBD did not significantly affect the risk of neoplasia. Conclusion. The even higher risk of colorectal neoplasia in PSC-IBD patients after when compared with that of before Ltx underscores the importance of regular surveillance colonoscopies post-Ltx. The association of aminosalicylates and ursodeoxycholic acid to the development of colorectal neoplasia after Ltx should be further investigated.  相似文献   
18.
19.

Objective

To compare the spatial distribution of motor units recruited in tibialis anterior (TA) when electrical stimulation is applied over the TA muscle belly versus the common peroneal nerve trunk.

Methods

Electromyography (EMG) was recorded from the surface and from fine wires in superficial and deep regions of TA. Separate M-wave recruitment curves were constructed for muscle belly and nerve trunk stimulation.

Results

During muscle belly stimulation, significantly more current was required to generate M-waves that were 5% of the maximal M-wave (Mmax; M5%max), 50% Mmax (M50%max) and 95% Mmax (M95%max) at the deep versus the superficial recording site. In contrast, during nerve trunk stimulation, there were no differences in the current required to reach M5%max, M50%max or M95%max between deep and superficial recording sites. Surface EMG reflected activity in both superficial and deep muscle regions.

Conclusions

Stimulation over the muscle belly recruited motor units from superficial to deep with increasing stimulation amplitude. Stimulation over the nerve trunk recruited superficial and deep motor units equally, regardless of stimulation amplitude.

Significance

These results support the idea that where electrical stimulation is applied markedly affects how contractions are produced and have implications for the interpretation of surface EMG data.  相似文献   
20.
BackgroundLaparoscopic fenestration has largely replaced open fenestration of liver cysts. However, most hepatectomies for polycystic liver disease (PCLD) are performed open. Outcomes data on laparoscopic hepatectomy for PCLD are lacking.MethodsPatients who underwent surgery for PCLD at a single institution between 2010 and 2019 were reviewed and grouped by operative approach. Pre- and post-operative volumes were calculated for patients who underwent resection. Primary outcomes were: volume reduction, re-admission and postoperative complications.ResultsTwenty-six patients were treated for PCLD: 13 laparoscopic fenestration, nine laparoscopic hepatectomy, three open hepatectomy and one liver transplantation. Median length of stay for patients after laparoscopic resection was 3 days (IQR 2–3). The only complication was post-operative atrial fibrillation in one patient. There were no readmissions. Overall volume reduction was 51% (range 22–69) for all resections, 32% (range 22–46) after open resection and 56% (range 39–69) after laparoscopic resection.ConclusionVolume reduction achieved through laparoscopic approach exceeded open volume reduction at this institution and is comparable to volume reduction in previously published open resection series. Adequate volume reduction can be accomplished by laparoscopic means with acceptable postoperative morbidity.  相似文献   
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