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61.
A 44-year-old patient progressed from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH) cirrhosis. She was diagnosed with NAFL via a liver biopsy. At 56 years old, she was diagnosed with NASH stage 3 via a second liver biopsy. One year later, she was diagnosed with NASH cirrhosis via a third liver biopsy. This is the first study to report the gradual deterioration of liver histology shown via three liver biopsies and fibrosis markers in a patient who progressed from NAFL to NASH cirrhosis. Following menopause, it is necessary to be aware of the rapid development of liver fibrosis.  相似文献   
62.
Management of post-transplant complications caused by severe adenoviral infection remains a major therapeutic challenge. A 17-year-old male who had undergone bone marrow transplantation for the treatment of acute lymphoblastic leukemia developed complete anuria following hemorrhagic cystitis 34 days after the transplant procedure. The computed tomogram scan revealed bilateral hydronephrosis, indicating acute renal failure because of obstructive uropathy. The emergency procedure of percutaneous nephrostomy caused massive bleeding in the left kidney, which eventually required a nephrectomy. Adenovirus-positive severe necrotizing tubulointerstitial nephritis was the histopathological diagnosis. Post-transplant acute renal failure because of hydronephrosis, which could be complicated by adenovirus-induced renal parenchymal disease, is of great concern and may cause significant problems with interventional treatment.  相似文献   
63.
We observed 2 cases of repeated episodes of syncope after alcohol ingestion. Both patients were light drinkers and had carotid sinus hypersensitivity. In both cases, alcohol loading tests repeatedly induced sinus bradycardia and hypotension 1.0-1.5 hours after drinking alcohol. Atropine was effective in improving symptoms. A loading test using a glucose solution of equivalent osmolarity and volume was negative. Acute alcohol ingestion usually increases heart rate with variable effects on blood pressure. However, our 2 cases exhibited unusual alcohol-induced sinus bradycardia and hypotension, suggesting a paradoxical increase in parasympathetic activity and/or decrease in sympathetic activity.  相似文献   
64.
OBJECTIVE: To compare concentrations of joint biomarkers in synovial fluid (SF) between idiopathic osteonecrosis of the femoral head (ION) and osteoarthritis (OA) of the hip joint. METHODS: Levels of the joint biomarkers cartilage oligomeric matrix protein (COMP), antigenic keratan sulfate (AgKS), and hyaluronan (HA) in SF samples from 21 cases of ION and their relationship to disease stage and history of steroid use were assessed and compared to the result of 29 cases of hip OA. RESULTS: In both the ION and hip OA groups, levels of COMP and AgKS in SF showed a significant positive correlation. The ION group had significantly higher levels of AgKS in SF than the hip OA group. In the ION group, stage II patients had significantly higher SF levels of both COMP and AgKS than those in stage III patients. No difference in level of HA in hip joint SF was found between steroid and non-steroid treated ION patients or between the stage II and III subgroups. CONCLUSION: SF levels of COMP and AgKS may serve as useful joint biomarkers that reflect cartilage metabolism not only in hip OA but also in ION.  相似文献   
65.
Annals of Nuclear Medicine - Amyloid positron emission tomography (PET) can reliably detect senile plaques and fluorinated ligands are approved for clinical use. However, the clinical impact of...  相似文献   
66.
Despite >50 years of research work since the discovery of sliding filament mechanism in muscle contraction, structural details of the coupling of cyclic cross-bridge movement to ATP hydrolysis are not yet fully understood. An example would be whether lever arm tilting on the myosin filament backbone will occur in the absence of actin. The most direct way to elucidate such movement is to record ATP-induced cross-bridge movement in hydrated thick filaments. Using the hydration chamber, with which biological specimens can be kept in an aqueous environment in an electron microscope, we have succeeded in recording ATP-induced cross-bridge movement in hydrated thick filaments consisting of rabbit skeletal muscle myosin, with gold position markers attached to the cross-bridges. The position of individual cross-bridges did not change appreciably with time in the absence of ATP, indicating stability of time-averaged cross-bridge mean position. On application of ATP, individual cross-bridges moved nearly parallel to the filament long axis. The amplitude of the ATP-induced cross-bridge movement showed a peak at 5–7.5 nm. At both sides of the filament bare region, across which the cross-bridge polarity was reversed, the cross-bridges were found to move away from, but not toward, the bare region. Application of ADP produced no appreciable cross-bridge movement. Because ATP reacts rapidly with the cross-bridges (M) to form complex (M·ADP·Pi) with an average lifetime >10 s, the observed cross-bridge movement is associated with reaction, M + ATP → M·ADP·Pi. The cross-bridges were observed to return to their initial position after exhaustion of ATP. These results constitute direct demonstration of the cross-bridge recovery stroke.  相似文献   
67.
Nodular gastritis in adults is caused by Helicobacter pylori infection   总被引:6,自引:0,他引:6  
A close relationship exists between nodular gastritis and Helicobacter pylori infection in children. The pathogenesis and optimal management of nodular gastritis in adults, however, are unclear. This study describes the clinicopathologic features of nodular gastritis in adults and correlates treatment with outcome. Of 97,262 adult patients who underwent endoscopy, 187 (0.19%) were diagnosed with nodular gastritis, 151 (81%) of whom had dyspepsia. Nodular gastritis predominantly affects young women (49 men and 138 women, mean age, 32.6 years). All 134 patients tested for Helicobacter pylori infection were infected, and 65/66 (98%) had inflammation of both the antrum and the corpus. Twenty-five (13%) had associated lesions (peptic ulcers or cancer). Dyspepsia improved after eradication of Helicobacter pylori infection, but did not improve spontaneously. Nodular gastritis in adults is caused by Helicobacter pylori infection and shows a predilection for females and young adults. Helicobacter pylori eradication decreases symptoms and reduces the risk of peptic ulcers and possibly gastric cancer.  相似文献   
68.
AIM: To examine Krüppel-like factor 6 (KLF6) mutations in nonpolypoid-type tumors and alterations of K-ras, p53,and B-raf in relation between mutation and morphologic type, particularly nonpolypoid-type colorectal carcinomas.METHODS: Fifty-five early nonpolypoid colorectal carcinomas were analyzed. Loss of heterozygosity (LOH) of KLF6 and p53 was determined by microsatellite assay.Mutations of KLF6, K-ras, and B-raf were examined by polymerase chain reaction-single-strand conformation polymorphism followed by direct sequencing. In LOH-positive and/or mutation-positive tumors, multiple (4-7) samples in each tumor were microdissected and examined for genetic alterations, p53 expression was evaluated by immunohistochemistry.RESULTS: LOH of KLF6 and p53 was found in 14 of 29 (48.3%) and 14 of 31 (45.2%) tumors, respectively. In 10 of the 14 (71.4%) KLF6 LOH-positive tumors and 9 of the 14 (64.3%) p53 LOH-positive tumors, LOH was found in all of the microdissected samples. In 1 of the 10 (10.0%) KLF6 LOH-positive tumors, a single missense mutation was identified. K-ras and B-raf mutations were found in 5 of 55 (9.1%) and 6 of 55 (10.9%) tumors,respectively. However, these mutations were detected only in subsets of microdissected tumor samples.CONCLUSION: These data suggest that KLF6 and p53 mutations are involved in the development of nonpolypoid colorectal carcinoma, whereas K-ras and B-raf mutations are not.  相似文献   
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