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1.
The association of bone with the metabolic syndrome and its features, visceral fat accumulation or insulin resistance, remains unclear. We determined visceral and subcutaneous fat areas (V and S) by computed tomography on 187 men (28–83 years) and 125 postmenopausal women (46–82 years) with type 2 diabetes. Men whose V was 100 cm2 or more had significantly lower urinary N-terminal cross-linked telopeptide of type-I collagen (p = 0.005), higher femoral neck bone mineral density (FN-BMD) (p = 0.004), and lower prevalence of vertebral fractures (VFs) (p = 0.04) than controls. Fat mass, V, S, and lean body mass positively correlated with FN-BMD in men and with lumbar (L) and FN-BMD in women. When adjusted for weight, these correlations became negative. Urinary C-peptide positively correlated with FN-BMD in both genders. Multivariate logistic regression analysis adjusted for age, height, weight, L-BMD, duration of diabetes, and diabetes therapies identified V in men and urinary C-peptide in women as factors inversely associated with the presence of VFs [odds ratio (OR) = 0.61 per SD increase, p = 0.04, and OR = 0.32, p = 0.01, respectively]. These findings suggest that, of the components of the metabolic syndrome, body fat in gravity and hyperinsulinemia could increase FN-BMD in diabetic subjects. Visceral fat in men and hyperinsulinemia in women may protect against VFs independent of weight, L-BMD, diabetes duration, or therapies.  相似文献   
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APC gene and mismatch repair genes. The role of these genes in colorectal carcinogenesis has been studied intensively. The adenoma–carcinoma sequence was initially proposed by Vogelstein, and the multistep carcinogenesis theory is now well accepted. The various functions of the APC gene have been elucidated. APC genes are considered to play a role in shedding of the epithelial cells into the lumen. The mechanism behind formation of a unicryptal adenoma is now better understood. Adenoma formation is a monoclonal event with two hits of the APC gene. There is no zonal extension of the proliferative zone in the background colonic mucosa of FAP patients. In addition to the adenoma–carcinoma sequence, there seem to be various carcinogenetic pathways in the development of colorectal cancer. A depressed type of early cancer was recently found by the use of magnifying endoscopy. The incidence of K- ras mutation was extremely low in this group of early cancers. Some of the minute cancers show the p53 mutation before the occurrence of APC mutation. Cancers of microsatellite mutator phenotype show exaggerated genomic instability at simple repeat sequences, such as TGFβRII. These genes may play a suppressor role in a p53 independent pathway of colorectal carcinogenesis. We are now in an exciting era of this progressing field of science. This genetic information may be more widely applicable clinically in the near future (e.g., for presymptomatic diagnosis, selection of patients for the most appropriate treatments, and assessment of malignant potential).  相似文献   
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Sodium valproate was administered to Jcl:ICR mice in order to evaluate teratogenicity in the cardiovascular system. A single dose of 600mg/kg of sodium valproate was injected intraperitoneally on gestational day 6, 7, 8 or 9. On day 18 of gestation, dams were laparotomized to observe incidence and type of cardiovascular abnormality in live fetuses. Cardiovascular abnormalities were found most frequently in the group treated on day 7, being recognized in 86% of litters (19/22) and in 29% of live fetuses (70/238). Among these, there were 28 cases of transposition of the great arteries, 13 of double outlet right ventricle, 11 of endocardial cushion defect, 9 of ventricular septal defect, 5 of tricuspid atresia, and 4 of hypoplastic left heart syndrome.  相似文献   
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The biodistribution and imaging characteristics of the 111In-labeled anti CEA monoclonal antibody ZCE-025 were studied in five patients with suspicion of colorectal carcinoma. Evaluation included antibody pharmacokinetics and assessment of antibody distribution in surgical specimen, making a comparison with whole-body imaging with a gamma camera. ZCE-025 localization in tumors was demonstrated by gamma-camera imaging in 4 of the 5 patients, corresponding to surgical findings. Persistent accumulation of 111In in the lymph nodes was observed in one patient, whereas surgical exploration of these lymph nodes showed no gross or microscopic evidence of metastases of colon carcinoma. Analysis of individual plasma by size exclusion HPLC showed two radioactivity peaks, labeled antibody and free DTPA. No transchelation of 111In to circulating transferrin was observed. The blood clearance was fitted to a two-compartment equation and its half-lives were found to be 10.8 +/- 8.7 h and 69.5 +/- 21.8 h for t1/2 alpha and t1/2 beta, respectively. Total urinary excretion averaged 0.3% of the injected dose/h with a small patient to patient variation. At 24 hrs postadministration the predominant radiolabeled species in urine was free DTPA. Thereafter, radioactivity in urine was partly present as a low molecular weight catabolic product. No apparent correlation between CEA content and uptake of 111In-ZCE-025 in tumors resected by surgery could be found. How 111In-labeled antibody is accumulated into tumors as well as into some nontumor tissues needs further study.  相似文献   
6.
Studies of human visual pathophysiology with visual evoked potentials.   总被引:2,自引:0,他引:2  
Visual evoked potentials (VEPs) offer reproducible and quantitative data on the function of the visual pathways and the visual cortex. Pattern reversal VEPs to full-field stimulation are best suited to evaluate anterior visual pathways while hemi-field stimulation is most effective in the assessment of post-chiasmal function. However, visual information is processed simultaneously via multiple parallel channels and each channel constitutes a set of sequential processes. We outline the major parallel pathways of the visual system from the retina to the primary visual cortex and higher visual areas via lateral geniculate nucleus that receive visual input. There is no best method of stimulus selection, rather visual stimuli and VEPs' recording should be tailored to answer specific clinical and/or research questions. Newly developed techniques that can assess the functions of extrastriate as well as striate cortices are discussed. Finally, an algorithm of sequential steps to evaluate the various levels of visual processing is proposed and its clinical use revisited.  相似文献   
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The purpose of this study was to evaluate the acute effects of corticosteroid and iodide preoperative therapy in patients with Graves' disease in terms of thyroid function and immunological parameters. The above combination was prescribed for 4 patients who had experienced severe side effects from antithyroid drugs (ATD) in order to reduce the possibility of post-thyroidectomy thyroid storm. Corticosteroids were employed daily for four days, and iodides were given daily for two weeks prior to thyroidectomy. The free T3 values decreased rapidly to euthyroid levels following the administration of both drugs, although the free T4 values were still much higher than normal in 3 of the 4 patients at the time of surgery. By comparison, 3 of 8 patients treated with ATD also had thyroid hormone levels above normal. Studies of lymphocyte subsets revealed that the percentage of helper T cells was significantly less in the corticosteroidiodide treatment group than in the control and ATD groups. It is thus possible that postoperative thyroid storm might be prevented through corticosteroid-iodide therapy by virtue of the reduction of free T3 values to within the normal range by the time of surgery. The acute suppression of helper T cells was another result of this form of therapy observed.  相似文献   
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The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors.  相似文献   
10.
Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma.  相似文献   
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