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Progressive familial intrahepatic cholestasis (PFIC) is a heterogenous group of disorders with various etiologies. Recent molecular and genetic studies have categorized the spectrum of types. Liver transplantation is a curative modality of treatment in this disease. We report our experience with 13 patients with PFIC who underwent living related liver transplantation. The follow-up periods ranged from 12 to 50 months. Two children died at 1 and 2 years posttransplantation, leading to a decrease in survival rate from 100% in the first year to 84.6%.  相似文献   
43.
Delayed graft function. Influence on outcome and strategies for prevention.   总被引:4,自引:0,他引:4  
Delayed graft function remains a prevalent problem in cadaveric renal transplantation that increases rejection, decreases graft and patient survival, increases the cost of transplantation, and complicates patient management. Although current medical and surgical strategies can reduce the incidence of DGF to 20% or less, newer therapies that focus on nonimmune and immune forms of renal injury are needed to improve outcomes further.  相似文献   
44.
Modern endoscopes play a significant role in diagnosing various gastrointestinal (GI) tract related diseases where the visual quality of endoscopic images helps improving the diagnosis. This article presents an image enhancement method for color endoscopic images that consists of three stages, and hence termed as “Tri-scan” enhancement: (1) tissue and surface enhancement: a modified linear unsharp masking is used to sharpen the surface and edges of tissue and vascular characteristics; (2) mucosa layer enhancement: an adaptive sigmoid function is employed on the R plane of the image to highlight micro-vessels of the superficial layers of the mucosa and submucosa; and (3) color tone enhancement: the pixels are uniformly distributed to create an enhanced color effect to highlight the subtle micro-vessels, mucosa and tissue characteristics. The proposed method is used on a large data set of low contrast color white light images (WLI). The results are compared with three existing enhancement techniques: Narrow Band Imaging (NBI), Fuji Intelligent Color Enhancement (FICE) and i-scan Technology. The focus value and color enhancement factor show that the enhancement level achieved in the processed images is higher compared to NBI, FICE and i-scan images.  相似文献   
45.
The matrix metalloproteinases (MMPs) are a family of extracellular matrix-cleaving enzymes involved in ovarian remodeling. In many non-tropical species, including Siberian hamsters, ovarian remodeling is necessary for the functional changes associated with seasonal reproduction. We evaluated MMPs and their endogenous inhibitors (TIMPs), during photoperiod-induced ovarian recrudescence in Siberian hamsters. Hamsters were transferred from long day (LD; 16:8) to short day (SD; 8:16) photoperiods for 14weeks, and then returned to LD for 0, 1, 2, 4, or 8weeks for collection of ovaries and plasma. Post-transfer (PT) LD exposure increased body and ovarian mass. Number of corpora lutea and antral, but not preantral follicles increased in PT groups. Plasma estradiol concentrations were lower in PT weeks 0-4, and returned to LD levels at PT week 8. No change was observed in relative MMP/TIMP mRNA levels at PT week 0 (SD week 14) as compared to LD. Photostimulation increased MMP-2 mRNA at PT week 8 as compared to PT weeks 0-1. MMP-14 mRNA expression peaked at PT weeks 1-2 as compared to LD levels, while MMP-13 expression was low during this time. TIMP-1 mRNA peaked at PT week 8 as compared to PT weeks 0-4. No changes were noted in MMP-9 and TIMP-2 mRNA expression. In general, MMP/TIMP protein immunodetection followed the same patterns with most staining occurring in granulosa cells of follicles and corpora lutea. Our data suggest that mRNA and protein for several members of the MMP/TIMP families are expressed in Siberian hamster ovaries during recrudescence. Because of the variation observed in expression patterns, MMPs and TIMPs may be differentially involved with photostimulated return to ovarian function.  相似文献   
46.
Twenty-five percent of the world’s population could be suffering parasitic infestation. Highest prevalence is in underdeveloped agricultural and rural areas in the tropical and subtropical regions. In some areas incidence may reach 90% of the population. In contrast, some major economic projects intended to promote local development have, paradoxically, caused parasitic proliferation, e.g. bilharziasis in Egypt and Sudan and Chagas disease in Brazil. The commonest cosmopolitan gastrointestinal parasite is Entamoeba histolytica. Some intestinal parasite are endemic in temperate climates, e.g. Entrobius vermicularis. The AIDS epidemic has increased the prevalence and severity of parasitic disease, particularly Strongyloides stercolaris. Tropical parasites are seen in Western people who travel to tropical countries. Radiology has acquired a major role in diagnosis and management of gastrointestinal parasite infestations and their complications.  相似文献   
47.
Multiple primary tumors in patients diagnosed with hypopharyngeal cancer.   总被引:2,自引:0,他引:2  
OBJECTIVE: There have been few series to report on the incidence of multiple primary tumors associated with hypopharyngeal cancer. A unique consecutive patient group in a closed community who were treated by a single surgeon was available. The incidence and effect of multiple primary tumors were unknown. STUDY DESIGN: We sought to assess (1) the incidence of multiple primary tumors among patients with hypopharyngeal cancer who were treated at a tertiary center, (2) the incidence of synchronous and metachronous tumors, and (3) the location of these multiple primary tumors and their effect on patient survival. METHODS: We conducted a retrospective study of case notes of 150 consecutive patients with hypopharyngeal malignancy treated by a single surgeon between 1983 and 1998. Information was compiled from the patients' medical records and death data from the Family Health Services Authority. RESULTS: Thirty-four patients had multiple primary tumors (22.6%). There were 22 men and 12 women; piriform fossa tumor was seen in 21 men and 6 women, and postcricoid space tumor was seen in 6 women and 1 man. Second primary tumors were synchronous in 7 patients, subsequent to hypopharyngeal tumor in 5 patients, and antecedent to hypopharyngeal tumor in 14 patients. Eight patients had 2 primary tumors, of which 4 were synchronous, 4 were subsequent, and 8 were antecedent to hypopharyngeal malignancy. On the last review (2001), 3 patients were alive, and 31 had died: 17 had died from primary malignancy, 11 from another malignancy, and 3 from unrelated causes. CONCLUSION: The presence of second primary tumors in hypopharyngeal cancer is higher than previously reported, and their presence had a significant effect on the patients' survival.  相似文献   
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49.
PurposeRadiation therapy for mesothelioma remains challenging, as normal tissue toxicity limits the amount of radiation that can be safely delivered to the pleural surfaces, especially radiation dose to the contralateral lung. The physical properties of proton therapy result in better sparing of normal tissues when treating the pleura, both in the postpneumonectomy setting and the lung-intact setting. Compared with photon radiation, there are dramatic reductions in dose to the contralateral lung, heart, liver, kidneys, and stomach. However, the tissue heterogeneity in the thorax, organ motion, and potential for changing anatomy during the treatment course all present challenges to optimal irradiation with protons.MethodsThe clinical data underlying proton therapy in mesothelioma are reviewed here, including indications, advantages, and limitations.ResultsThe Particle Therapy Cooperative Group Thoracic Subcommittee task group provides specific guidelines for the use of proton therapy for mesothelioma.ConclusionsThis consensus report can be used to guide clinical practice, insurance approval, and future research.  相似文献   
50.
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