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101.
Material and methods We analyzed the expression of hypoxia inducible factor-1α (HIF-1α) and glucose transporter-1 (GLUT-1) by immunohistochemistry in ovarian serous and mucinous tumors from the point view of the histological characteristics and acquisition of malignancy. A total of 102 ovarian tumors were examined, composed of 31 adenomas (serous 17 and mucinous 14), 32 borderline tumors (serous 13 and mucinous 19), and 39 adenocarcinomas (serous 21 and mucinous 18). Results The overall positive ratios were as follows: HIF-1α, 74% of adenomas, 91% of borderline tumors, and 100% of adenocarcinomas; and GLUT-1, 68% of adenomas, 95% of borderline tumors, and 100% of adenocarcinomas. Comparing serous tumors and mucinous tumors, there was no significant difference in the positive ratios of HIF-1α and GLUT-1 of adenomas, borderline tumors, and adenocarcinomas. However, both markers were more strongly expressed in serous adenocarcinomas (HIF-1α, 3 + 100%; GLUT-1, 3 + 76%) than in mucinous adenocarcinomas (HIF-1α, 3 + 61%; GLUT-1, 3 + 28%). The results of immunoblotting and mRNA expression level analyses corresponded with those of immunohistochemical expression profiles. DNA binding assay also demonstrated that HIF-1 is more commonly activated in serous adenocarcinomas than in mucinous adenocarcinomas. Conclusion HIF-1α and GLUT-1 expressions seemed to be coordinated to adapt ovarian tumor cells into hypoxic conditions in close association with the acquisition of malignancy. We consider that the relatively strong expression of both markers in serous tumors compared with mucinous tumors is related to the difference in their histological characteristics.  相似文献   
102.
In the present study, we demonstrated that hypertensive left ventricular hypertrophy can be divided angiographically into symmetrical (SH) and asymmetrical septal hypertrophy (ASH) groups. In the SH group, the dynamics of the septal wall and the free wall were almost the same as those of the control group. On the other hand, the ASH group rather resembled the HCM group in the thickness and dynamics of the septal wall and the free wall as well as in the septal configuration. The most characteristic difference of the ASH and HCM groups from the SH group was in the significantly greater thickness of the septal wall at end diastole. However, in view of the developmental mechanism of hypertensive heart, it is interesting to note that the more the septal-free wall ratio increases, the more the thickness of the septal wall increases in the SH group.  相似文献   
103.
BACKGROUND: Although Bcl-2 is well known to have anti-apoptotic activities in vitro and in vivo, the role of Bcl-2 relating to liver regeneration remains controversial. The aim of this study was to document the effect of Bcl-2 expression on liver regeneration in rats undergoing a partial hepatectomy. MATERIAL AND METHODS: Adult male Wistar rats (n = 4/group) at 72 h before undergoing a 70% partial hepatectomy (PH) were administered 1 x 10(9) plaque-forming units of adenovirus vector encoding either human Bcl-2 (group 1) or LacZ (group 2) intravenously and were sacrificed at 0, 12 h, and at 1, 2, 3, 7, 14, and 21 days postoperatively. In group 3, normal saline was injected instead of adenovirus vector. Liver regeneration was monitored by measuring the restituted liver mass and proliferating cell nuclear antigen (PCNA) immunostaining. The incidence of apoptosis in the liver was analyzed by the immunohistochemical detection of single-stranded DNA at 14 and 21 days postoperatively. RESULTS: The restituted liver mass showed significantly higher values in group 1 (26.1 +/- 7.2%) than in group 2 (14.7 +/- 6.8%) and 3 (13.6 +/- 5.0%) at 1 day after PH (P < 0.05). The PCNA labeling index was significantly higher in group 1 (47.2 +/- 9.9%) than in groups 2 (19.0 +/- 7.8%) and 3 (19.2 +/- 15.2%) at 1 day after a partial hepatectomy (P < 0.05). The hepatocyte growth factor (HGF) mRNA expression was significantly lower in group 1 than in group 2 at 12 h after PH (P < 0.05). The number of single-stranded DNA-positive cells decreased significantly more in group 1 (5.67 +/- 1.53 positive cells/10 fields per tissue) than those in group 2 (18.33 +/- 7.57 positive cells/10 fields per tissue) at 14 days after PH. CONCLUSIONS: These results thus indicated that an overexpression of anti-apoptotic protein Bcl-2 does not necessarily have an anti-apoptotic effect on liver regeneration but appears to have a pro-proliferative effect in the early phase of liver regeneration.  相似文献   
104.
Stercoraceous perforation of the sigmoid colon has rarely been reported in the literature. This lesion is assumed to be produced by the pressure from a hard scybalum resulting in a perforated ulcer with necrotic edges. Two cases of stercoraceous perforation of the sigmoid colon are presented in this paper. It is difficult to diagnose this lesion preoperatively, although ultrasonograms proved useful in showing the colon perforation. This lesion should always be suspected when a patient who has had chronic constipation presents with sudden severe abdominal pain. It is possible that this lesion is becoming more common as the mean age of the population increases and we stress the importance of immediate surgery and intensive care for improving the prognosis.  相似文献   
105.
We report two cases of atraumatic iliopsoas hematoma. First patient was a 76-year-old man admitted to our hospital from appetite loss. Blood transfusion did not improve his anemia. Five days after admission, suddenly he went into shock. CT scan revealed ileopsoas hematoma. He died from hemorrhagic shock in spite of conservative therapy. Second patient was a 70-year-old man admitted because of acute heart failure. Continuous hemodiafiltration was required to relieve anuria. The next day, he developed left leg and hip pain. CT scan revealed ileopsoas hematoma and he received CT guided aspiration drainage for decompression, but almost 7 days were needed to achieve successful pain control. In a case of iliopsoas hematoma, early diagnosis and adequate choise of therapy are necessary to improve prognosis of patients.  相似文献   
106.
A 54-year-old man was admitted to our hospital due to intermittent chest pain. He had a history of acute myocardial infarction, and peri-stent contrast staining had been observed at the stent implantation site. The patient previously underwent anticoagulation therapy for left ventricular thrombus and antiplatelet therapy to prevent stent thrombosis. More than one year after implantation of a drug-eluting stent, antiplatelet drugs were discontinued, and anticoagulant alone was prescribed according to the guidelines, which resulted in very late stent thrombosis. The risks of both bleeding and thrombosis must be fully considered when deciding whether or not to discontinue antiplatelet therapy during anticoagulation therapy.  相似文献   
107.
108.
109.
Vasospastic angina in Kawasaki disease   总被引:1,自引:0,他引:1  
We report vasospastic angina in a young female with a history of Kawasaki disease (KD). She had had KD at the age of 20 months. Selective coronary angiograms at the age of 4 years revealed no coronary aneurysms or stenosis. She remained symptom-free for 29 years, but coronary angiograms at the age of 31 years revealed a localized 50% stenosis of the left anterior descending artery. Aging in addition to endothelial dysfunction of the coronary arterial wall resulting from acute KD vasculitis may underlie the late development of angina. This is the first case which is reported as vasospastic angina after KD. The occurrence of acute coronary syndromes in patients with a history of KD should be investigated carefully from now on. Attention should be paid to coronary endothelial dysfunction after KD in adults.  相似文献   
110.
Troglitazone and D-chiroinositol have been shown to exert antidiabetic effects by either potentiating or mimicking insulin action. We studied whether pretreatment with these compounds can prevent the deleterious effects of glucosamine on insulin action that may play an important role in hyperglycemia-induced insulin resistance. Normal Wistar rats were pretreated with troglitazone (100 mg/kg/d), D-chiroinositol (100 mg/kg/d), or placebo (saline) for 7 days. Glucosamine (50 micromol/kg/min) was then infused for 210 minutes, and a euglycemic glucose clamp was performed during the last 120 minutes. Pretreatment with troglitazone or D-chiroinositol had no effect on fasting plasma glucose or insulin or basal hepatic glucose output (HGO). Under the euglycemic-hyperinsulinemic (956+/-93 pmol/L) clamp condition, HGO in glucosamine-infused placebo-treated rats was not suppressed, but instead was increased over the basal level, indicative of hepatic insulin resistance. In contrast, HGO failed to increase during glucosamine infusion in rats pretreated with troglitazone but was not normally suppressed. This may indicate a partial improvement in the hepatic insulin resistance. D-Chiroinositol pretreatment had no effect on the glucosamine-induced increase in HGO. The glucose disposal rate (GDR) was 25% lower in rats infused with glucosamine versus saline-infused rats (25.5+/-2.5 v 34.1+/-2.0 mg/kg/min), indicative of peripheral insulin resistance. Pretreatment with D-chiroinositol (34.5+/-2.3 mg/kg/min) prevented the glucosamine-induced decrease in the GDR, indicating an improvement in peripheral insulin resistance. Troglitazone (25.2+/-3.3 mg/kg/min) was without effect. In conclusion, (1) in normal control rats, glucosamine infusion induced hepatic and peripheral insulin resistance; (2) D-chiroinositol, but not troglitazone, pretreatment prevented glucosamine-induced peripheral insulin resistance; and (3) troglitazone, but not D-chiroinositol, partially blocked the glucosamine-induced hepatic insulin resistance. D-Chiroinositol may provide a novel pharmacological approach to hexosamine-induced peripheral insulin resistance.  相似文献   
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