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91.
The effect of methanol extractives from tea leaves on hypercholesterolemia was examined in animal models. It was found that orally administered (-)-epicatechin gallate and (-)-epigallocatechin gallate from tea leaves lowered the serum cholesterol level in mice fed a high fat emulsion. Quantitation of tissue cholesterol and examination of liver tissues in mice fed a high cholesterol diet revealed that these constituents also significantly lowered the amount of cholesterol crystallization. These results support the reputed effectiveness of tea use in hypercholesterolemia.  相似文献   
92.
Free and acylcarnitine in serum and urine samples were measured in five patients with hyperammonemia associated with anticonvulsant therapy including sodium valproate, of whom three had a Reye-like syndrome. All had considerable reduction in serum free carnitine and slight increase of acylcarnitine concentrations, suggesting increased conversion of free to acylcarnitine by valproate administration. Urinary excretion of both free and acylcarnitine was increased, accompanied by depressed reabsorption of free carnitine and decreased acylcarnitine/free carnitine clearance ratio. These results indicate a decreased threshold for free carnitine. The combination of these several factors may be responsible for carnitine deficiency in patients with hyperammonemia taking valproate.  相似文献   
93.
A zinc balance study was conducted on low birth weight infants (670 to 2420 g) fed unsupplemented human milk (the mother's or pooled) (group 1, n = 17) or human milk with zinc supplementation (group 2, n = 17). The mean zinc concentrations of the diets in groups 1 and 2 were 2.2 +/- 1.1 mg/L and 8.4 +/- 0.8 mg/L, respectively, and the mean copper concentration of the diets in both groups was 0.45 +/- 0.12 mg/L. The studies were performed 7 to 128 days after birth, which corresponded to 29 to 43 weeks postconceptional age. The turning point of zinc balance from negative to positive appeared to be greatly influenced by the postconceptional age, being approximately 36 weeks in both group 1 and group 2, rather than other factors such as the zinc intake and the postnatal age. The calculated minimal requirement of dietary zinc during the period from 36 to 40 weeks postconceptional age, for an adequate amount of zinc retention in infants (250 micrograms/kg/d), was 0.8 mg/kg/d. Zinc supplementation did not appear to interfere with copper retention.  相似文献   
94.
Prognostic significance of Bcl-xL in human hepatocellular carcinoma   总被引:10,自引:0,他引:10  
BACKGROUND: Proliferation and apoptosis of liver cancer cells are closely related phenomena. We investigated the correlation between overexpression of Bcl-xL, an anti-apoptosis-related protein of the Bcl-2 family, and the clinical course of hepatocellular carcinoma (HCC). METHODS: Specimens from 7 HCC patients were used for Western blotting and immunoelectron microscopy tests. Samples from 33 HCC patients who had undergone hepatectomies were used for immunohistochemical staining. The degrees of expression of Bcl-xL and Ki-67, as an index of HCC mitosis severity, were each classified into 2 groups. RESULTS: With the use of Western blot analysis, enhanced immunoreactivity of Bcl-xL was found in cancerous specimens. Bcl-xL overexpression was found in cancer specimens in 21 of 33 patients (63.6%). The overall survival (P=.019) and disease-free survival (P=.030) rates of the group overexpressing Bcl-xL were definitely poorer. The Ki-67 higher labeling index LI > 10) group had a poorer survival rate (P=.016). There were significant correlations between Bcl-xL and overall survival and disease-free survival. Multivariate analyses revealed that Bcl-xL, tumor size, histologic portal invasion, and histologic metastatic foci were independent prognostic factors for overall survival and disease-free survival. CONCLUSIONS: These results showed Bcl-xL in HCC specimens, suggesting that Bcl-xL was a significant prognostic factor for disease progression in human HCC.  相似文献   
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96.
BACKGROUND: Pancreaticobiliary maljunction (PBM) is frequently associated with congenital choledochal cyst (CCBD), but differs in embryonic cause and clinical features. It is thought to develop as a misarrangement of the embryonic connections in the pancreaticobiliary ductal system, with the terminal bile duct joined to one of the ducts of the ventral pancreas. Clinical aspects are intermittent abdominal pain, relapsing acute pancreatitis, jaundice, cholangitis, and gallbladder cancer. In patients with PBM and CCBD, primary bile duct stones, acute cholangitis, and bile duct cancer are considered to result from cholestasis, regurgitation of pancreatic juice, and reciprocal reflux of bile and pancreatic juice. The mixture of bile and pancreatic juice due to recipocal reflex very likely plays an important role in biliary carcinogenesis. PATIENTS AND METHODS: We reviewed the pathophysiological and clinical aspects and biliary carcinogenesis in 250 PBM patients (169 with benign hepatobiliary and pancreatic disease, 81 with malignancy). RESULTS: PBM patients show elevated cellular proliferation activity in the gallbladder epithelia. A number of oncogenes and tumor suppressor genes have been identified and implicated in carcinogenesis, particularly the K- ras oncogene and the p53 suppressor gene. Some K- ras mutations do not appear essential for hyperplasia but may be an early event in carcinogenesis. The p53 mutations are involved in carcinogenesis in the biliary epithelium in PBM patients.  相似文献   
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99.
We describe a 37-year-old man complaining of right back pain and gait disturbance. He had a big soft tumor on his right back, hemihypertrophy of the right lower extremity, and right thoracic scoliosis. We diagnosed Klippel-Trenaunay-Weber syndrome based on the pathological findings of the soft tumor. Computed tomography (CT) scan revealed severe spinal stenosis due to a hypertrophic vertebral body and facet joint at T7. Treatment by decompression of hypertrophic bone led to complete neurological recovery. To our knowledge, no case has been reported of Klippel-Trenaunay-Weber syndrome with myelopathy which originated from thoracic scoliosis with a hypertrophic facet joint and vertebral body. We suggest that the cause of myelopathy in Klippel-Trenaunay-Weber syndrome originated not only from arteriovenous fistula, medullary angioma, and extradural hemangioma but also vertebral hypertrophy with scoliosis.  相似文献   
100.
 Osteochondroma is a common benign bone tumor that sometimes causes vascular complications when the lesion is situated near the knee. Venous complications are seen less frequently. We report two cases of solitary osteochondroma that arose in the distal femur. The patients were an 11-year-old boy and a 16-year-old boy, both of whom were suffering from bone protuberance and lower leg swelling due to congestion. In both patients, magnetic resonance imaging (MRI) revealed dilated popliteal veins at a site distal from the tumors or superficial veins. MR angiography (MRA) showed compressed popliteal arteries, and Doppler ultrasonography revealed weaker blood flow in the dorsalis pedis arteries in the lower leg with the tumor than in the other lower leg. The former patient complained of pain due to swelling in the lower leg, and for this reason the patient underwent resection of the tumor. After resection, both the swelling and the pain were decreased, and Doppler ultrasonography also revealed normal blood flow in the artery. The latter patient had swelling, but no pain, in the lower leg, and accordingly this patient has been followed carefully without resection, since there is always the possibility of irreversible vascular damage caused by osteochondroma, such as arterial or venous occlusion. We present two patients with osteochondroma, both of whom suffered from swelling of the lower leg due to venous compression by the tumor. In both cases, MRI and MRA were useful to show the presence of vascular compression. Doppler ultrasonography could also reveal the blood flow disturbance objectively, even in current osteochondroma cases in which there were no arterial symptoms. Received: November 26, 2001 / Accepted: March 7, 2002  相似文献   
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