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961.
962.
BACKGROUND: Hepatocellular carcinoma (HCC) is a well-known cancer involving the Wnt pathway in its carcinogenesis. AIMS: However, it is not clear whether these genetic changes are early genetic events in hepatocarcinogenesis or not. METHOD: In this study, we performed mutational analysis of the beta-catenin and AXIN I genes, and immunohistochemistry for beta-catenin in a series of 114 hepatocellular nodular lesions, including premalignant lesions such as low-grade dysplastic nodules (LGDNs) and high-grade dysplastic nodules (HGDNs). RESULTS: In the present study, mutations of the beta-catenin and AXIN I genes were detected in 16% (13 out of 81) and 6.2% (five of 81) of the HCCs, respectively. However, no mutations were found in 14 LGDNs and 19 HGDNs. Moreover, abnormal nuclear beta-catenin immunostaining was observed in 30 of 81 HCCs, but not in dysplastic nodules. CONCLUSION: Taken together, our data suggest that beta-catenin stabilization because of either beta-catenin or AXIN I mutation might be a late event for malignant progression rather than an early genetic event involving the initiation of HCC development.  相似文献   
963.
OBJECTIVES: To investigate neural representation evoked by acupuncture from human somatosensory cortices, especially from primary (SI) and secondary (SII) somatosensory areas. DESIGN AND SETTING: Neuroimaging study - Blood-oxygenation-level-dependent (BOLD) functional MRI was performed during acupuncture on LI4 (n=12 healthy participants). Sham acupuncture and innocuous tactile stimulation were also applied on the same acupuncture site as control comparisons. OUTCOME MEASURES: Responsive neural substrates were visualized and identified based on both individual and group-level surface activation maps. RESULTS: Discrete regions within the precentral gyrus (area 4) and the fundus of the central sulcus (area 3a) were selectively activated during the real acupuncture stimulation. In SII, the activation was extended in a postero-inferior direction to the fundus of the lateral sulcus. CONCLUSION: This specific pattern of acupuncture-related activation indicates that deep tissue stimulation (as seen in area 3a activation) and concurrent processing of sensory stimulation (as seen in activation in SII) may mediate neural responses to manual acupuncture.  相似文献   
964.
Meckel's diverticulum results from incomplete closure of the omphalomesenteric duct, and is the most common congenital anomaly of the small intestine. We present a case report of a 42-year-old patient who developed a strangulated intestinal obstruction as a complication of Meckel's diverticulum. The strangulated bowel obstruction was suggested by contrast-enhanced computed tomography. He recovered after a diverticulectomy and had no need for a small bowel resection.  相似文献   
965.
Claudin-7 has recently been suggested to be a distal nephron marker. We tested the possibility that expression of claudin-7 could be used as a marker of renal tumors originating from the distal nephron. We examined the immunohistochemical expression of claudin-7 and parvalbumin in 239 renal tumors, including 179 clear cell renal cell carcinoma (RCC)s, 29 papillary RCCs, 20 chromophobe RCCs, and 11 renal oncocytomas. In addition, the methylation specific-PCR (MSP) of claudin-7 was performed. Claudin-7 and parvalbumin immunostains were positive in 3.4%, 7.8% of clear cell RCCs, 34.5%, 31.0% of papillary RCCs, 95.0%, 80.0% of chromophobe RCCs, and 72.7%, 81.8% of renal oncocytomas, respectively. The sensitivity and specificity of claudin-7 in diagnosing chromophobe RCC among subtypes of RCC were 95.0% and 92.3%. Those of parvalbumin were 80.0% and 88.9%. The expression pattern of claudin-7 was mostly diffuse in chromophobe RCC and was either focal or diffuse in oncocytoma. All of the cases examined in the MSP revealed the presence of unmethylated promoter of claudin-7 without regard to claudin-7 immunoreactivity. Hypermethylation of the promoter might not be the underlying mechanism for loss of its expression in RCC. Claudin-7 can be used as a useful diagnostic marker in diagnosing chromophobe RCC and oncocytoma.  相似文献   
966.
Vaccination against hepatitis A virus (HAV) is recommended for patients with chronic liver disease (CLD), but this has been deemed unnecessary in Korea since the immunity against HAV was almost universal in adults. However, this practice has never been reevaluated with respect to the changing incidence of adult acute hepatitis A. We retrospectively reviewed the medical records of 278 patients with acute hepatitis A diagnosed from January 1995 to November 2005 and prospectively tested 419 consecutive CLD patients from July to December 2005 for the presence of IgG anti-HAV. The number of patients with acute hepatitis A has markedly increased recently, and the proportion of adult patients older than 30 yr has been growing from 15.2% during 1995-1999, to 28.4% during 2000-2005 (p=0.019). Among 419 CLD patients, the seroprevalences of IgG anti-HAV were 23.1% for those between 26 and 30 yr, 64% between 31 and 35 yr, and 85.0% between 36 and 40 yr. These data demonstrate that immunity against HAV is no more universal in adult and substantial proportion of adult CLD patients are now at risk of HAV infection in Korea. Therefore, further study on seeking proper strategy of active immunization against HAV is warranted in these populations.  相似文献   
967.
The plasma ghrelin has been reported to be elevated in Prader-Willi syndrome (PWS) and modulated by insulin. It was hypothesized that insulin might have a more pronounced effect on reducing plasma ghrelin in PWS patients, which would influence appetite. This study investigated the degree of ghrelin suppression using an euglycemic hyperinsulinemic clamp in children with PWS (n=6) and normal children (n=6). After a 90-min infusion of insulin, the plasma ghrelin level decreased from a basal value of 0.86+/-0.15 to 0.58+/-0.12 ng/mL in the controls, and from 2.38+/-0.76 to 1.12+/-0.29 ng/mL in children with PWS (p=0.011). The area under the curve below the baseline level over the 90 min insulin infusion was larger in children with PWS than in controls (-92.82+/-44.4 vs. -10.41+/-2.87 ng/mL/90 min) (p=0.011). The insulin sensitivity measured as the glucose infusion rate at steady state was similar in the two groups (p=0.088). The decrease in the ghrelin levels in response to insulin was more pronounced in the children with PWS than in the controls. However, the level of ghrelin was always higher in the children with PWS during the clamp study. This suggests that even though insulin sensitivity to ghrelin is well maintained, an increase in the baseline ghrelin levels is characteristic of PWS.  相似文献   
968.
Diagnosis of asthma is often challenging in primary-care physicians due to lack of tools measuring airway obstruction and variability. Symptom-based diagnosis of asthma utilizing objective diagnostic parameters and appropriate software would be useful in clinical practice. A total of 302 adult patients with respiratory symptoms responded to a questionnaire regarding asthma symptoms and provoking factors. Questions were asked and recorded by physicians into a computer program. A definite diagnosis of asthma was made based on a positive response to methacholine bronchial provocation or bronchodilator response (BDR) testing. Multivariate logistic regression analysis was used to evaluate the significance of questionnaire responses in terms of discriminating asthmatics. Asthmatic patients showed higher total symptom scores than non-asthmatics (mean 5.93 vs. 4.93; p<0.01). Multivariate logistic regression analysis identified that response to questions concerning the following significantly discriminated asthmatics; wheezing with dyspnea, which is aggravated at night, and by exercise, cold air, and upper respiratory infection. Moreover, the presence of these symptoms was found to agree significantly with definite diagnosis of asthma (by kappa statistics). Receiver-operating characteristic curve analysis revealed that the diagnostic accuracy of symptom-based diagnosis was high with an area under the curve of 0.647 +/- 0.033. Using a computer-assisted symptom-based diagnosis program, it is possible to increase the accuracy of diagnosing asthma in general practice, when the facilities required to evaluate airway hyperresponsiveness or BDR are unavailable.  相似文献   
969.
Because additive effects of inhaled corticosteroids and long-acting anticholinergics are unclear, we undertook this study to compare the efficacy of tiotropium alone and tiotropium plus budesonide in patients with chronic obstructive pulmonary disease. The study subjects were randomized to receive either tiotropium 18 microg once daily with or without budesonide 200 microg twice daily for 6 weeks. The efficacy variables were changes in trough forced expiratory volume in one second (FEV1), St. George's Respiratory Questionnaire (SGRQ), 6-minute walk distance (6MWD), and use of rescue medication. One hundred patients were randomized and 81 completed the study. The mean age was 64.0 yr, and the mean FEV1 was 39.7% predicted. Compared with tiotropium alone (N=40), the tiotropium/budesonide combination (N=41) was related to an improvement in the SGRQ total score (tiotropium -2.8 units and tiotropium/budesonide -5.6 units, p=0.003). 6MWD was improved by 13.5 m in the tiotropium group and by 22.5 m in the tiotropium/budesonide group (p=0.031). Changes in trough FEV1 and the use of rescue medication were similar between two groups. In conclusion, compared with tiotropium alone, the tiotropium/budesonide combination was related to an improved health-related quality of life. These data support that low-dose budesonide may enhance the efficacy of tiotropium.  相似文献   
970.
Permanent neonatal diabetes (PND) is a rare form of diabetes characterized by insulin-requiring hyperglycemia diagnosed within the first three months of life. In most cases, the causes are not known. Recently, mutations in the KCNJ11 gene encoding the Kir6.2 subunit of the ATP-sensitive K+ channel have been described in patients with PND. We report the first two Korean cases with PND due to a lysineto- arginine substitution at position 170 (K179R) and a valine-to-methionine substitution at position 59 (V59M) mutations of KCNJ11 encoding Kir6.2, respectively. After several years of insulin therapy, these patients were managed by oral glibenclamide therapy at a daily dose of 0.8-0.9 mg/kg. Their basal c-peptide levels increased after one week of glibenclamide therapy, and one month later, the insulin and c-peptide levels were in the normal ranges without any episodes of hyper- or hypoglycemia. These cases demonstrate that oral sulfonylurea may be the treatment of choice in PND patients with KCNJ11 mutations even at a young age.  相似文献   
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