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1.
Anthocyanins, which are responsible for a variety of bright colors (including red, blue, and purple) in fruits, vegetables, and flowers, are consumed as dietary polyphenols. Anthocyanin-containing fruits are thought to decrease coronary heart disease and are used in anti-diabetic preparations. Diabetes is associated with a variety of cardiovascular complications that may be mediated by endothelial dysfunction, and so this study was designed mainly to characterize the influence of a synthesized anthocyanidin derivative (HK-008) over acetylcholine (ACh)-induced relaxation in mesenteric arterial beds isolated from rats. In a glucose-tolerance test in intact rats, HK-008 (30 mg/kg) reduced the glucose level as effectively as the same dose of glibenclamide. The aortic relaxation induced by pinacidil (an ATP-sensitive potassium channel opener) was greatly inhibited by glibenclamide (10 microM), and also significantly inhibited by HK-008 (10 microM). Interestingly, the ACh-induced relaxation in the perfused, preconstricted mesenteric arterial bed was significantly enhanced by HK-008 (10 microM), and this enhancement was significantly attenuated by indomethacin (10 microM). The ACh-induced mesenteric relaxation was impaired by an increase in oxidative stress, viz. superoxide-generating treatment [xanthine oxidase (XO; 0.1 U/ml) plus hypoxanthine (HX; 10 microM)]. However, this impairment was strongly suppressed by HK-008 (10 microM). These results suggest that HK-008 increases endothelium-induced relaxation by suppressing oxidative stress or modulating prostanoids signaling. This compound may therefore be useful against certain cardiovascular disorders.  相似文献   
2.
The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones of 5-20 mm treated with ESWL were evaluated. Maximal dimension was measured on plain radiograph. From an attenuation value histogram graphed from the CT data, total stone volume and mean attenuation value were calculated. Seven stonestreets longer than 25 mm developed. There was no significant difference in maximal dimension and total stone volume between stones that did and stones that did not develop stonestreet. Mean attenuation value was the sole significant predictive factor. Application of mean attenuation value with cut-off level of 650 HU would anticipate stonestreet formation with a sensitivity of 85.7% and a specificity of 71.7%. The estimated risk of stonestreet formation is high in the treatment of stones with higher mean attenuation value.  相似文献   
3.
Community-acquired pneumonia is one of the major respiratory diseases causing hospital admission in previously healthy patients. Prompt and appropriate antibiotic selection is essential for recovery. The authors tried to determine the distribution of the etiologic agents of community-acquired pneumonias and to analyze predictive factors. Out of 188 cases of community-acquired pneumonia presenting to our hospital, etiologic agents were determined in 106 cases (56%). Twenty-nine cases were due to Streptococcus pneumoniae, 27 cases due to Mycoplasma, 17 cases due to Haemophilus influenzae and 21 cases due to Mycobacterium tuberculosis. M. tuberculosis was the cause in 11% of all cases and the importance of pulmonary tuberculosis must be emphasized as a community-acquired pneumonia. Out of 58 cases under 50 years old, Mycoplasma pneumoniae was the etiologic agent in 23 cases (40%) and S. pneumoniae in 7 cases (12%). Out of 62 cases not less than 70 years old. M. tuberculosis was the most common etiologic agent (15 cases, 24%). S. pneumoniae followed, being causative in 13 cases (21%). M. tuberculosis was the cause in 10 cases out of 31 cases who did not complain of fever at presentation. In 86 cases who did not show leukocytosis on admission, 21 cases were due to Mycoplasma (24%) and 15 cases were due to M. tuberculosis (17%). In particular 17 cases were due to Mycoplasma among 28 cases under 50 years old without leukocytosis (61%), and 11 cases were due to M. tuberculosis in the 27 cases no less than 70 years old without leukocytosis (41%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
The sensitivity, specificity, and accuracy of ultrasonography (US), dynamic incremented computed tomography (CT) with delayed phase imaging, and magnetic resonance imaging (MRI) with or without Gd-DTPA were studied for detecting the characteristic appearances of hepatocellular carcinomas (HCC): fibrous capsules, fibrous septa, and mosaic appearances. Results were prospectively evaluated in 30 patients who subsequently underwent hepatic lobectomies or segmentectomies. Pathologic evaluations of the resected liver specimens demonstrated fibrous capsules in 20 tumors (66.7%), fibrous septa in 13 tumors (43.3%), and mosaic appearances in 19 tumors (63.3%). The accuracies for fibrous capsules were 71.4% (20 of 28) for US, 81.5% (22 of 27) for CT, and 92.3% (24 of 26) for MRI. The accuracies for fibrous septa were 57.1% (16 of 28) for US, 59.3% (16 of 27) for CT, and 73.1% (19 of 26) for MRI. The accuracies for mosaic appearances were 71.4% (20 of 28) for US, 51.9% (14 of 27) for CT, and 69.2% (18 of 26) for MRI. Gd-DTPA administered MRI showed higher accuracies than did conventional MRI for all manifestations. In conclusion, the fibrous capsules of HCCs were readily detected by CT and MRI. Gd-DTPA administration demonstrated an advantage in clarifying fibrous capsules, as well as fibrous septa and mosaic appearances.  相似文献   
5.
We have successfully applied a reverse flow island flap of extensor digitorum brevis muscle for coverage of tissue defects in the distal portion of the foot dorsum in 2 patients. This flap covered the metatarsophalangeal area well with cadaver limb dissection and seems useful to cover the defect in the distal foot dorsum.  相似文献   
6.
Wilms tumor gene (WT-1) expression has been reported in many human cancers, including most ovarian and peritoneal serous carcinomas, but has not been studied in carcinomas of the fallopian tube. In this study, the authors evaluated the immunohistochemical expression of WT-1 in serous carcinomas of the fallopian tube and compared their reactivity with that of ovarian, peritoneal, and endometrial serous carcinomas. All primary serous carcinomas of the fallopian tube (13 cases), ovaries (25 cases), and peritoneum (3 cases) were reactive with the WT-1 antibody, whereas all five primary endometrial serous carcinomas were nonreactive. WT-1 reactivity in an unknown primary serous carcinoma is therefore suggestive of an extrauterine site. The marked difference in WT-1 staining raises the possibility of genetic differences between serous carcinomas arising in the endometrium compared with those arising in the ovaries, fallopian tubes, and peritoneum.  相似文献   
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We developed a new method for monitoring the cerebrovascular response to acetazolamide using technetium-99m diethylenetriaminepentaacetic acid human serum albumin (99mTc-DTPA-HSA). We infused 740 M Bq (20 mCi) of 99mTc-DTPA-HSA intravenously and carried out dynamic scanning of the anterior view of the head for 50 minutes. Ten minutes after the start of scanning, 1,000 mg of acetazolamide was injected intravenously. In three normal volunteers, the radioactivity in brain increased for an average of 8 minutes after the injection of acetazolamide and then remained relatively stable. The average of dilatation index [(peak count/the count just before acetazolamide injection-1)x 100] was 16.1. Our method enabled us to observe vasodilation caused by acetazolamide straight, and may be of value in assessing cerebral perfusion reserve easily and quantitatively.  相似文献   
10.
RATIONALE AND OBJECTIVES. The sialographic ductal patterns of the parotid glands in patients with Sj?gren syndrome were compared with those of normal patients by measuring the fractal dimensions. METHODS. Fractal dimensions were estimated using the modified pixel dilation method. RESULTS. The mean fractal dimension was 1.64 +/- 0.06 for the normal glands and 1.39 +/- 0.10 for the glands with Sj?gren syndrome (P < .005). No correlation between the age or sex and fractal dimension was observed for both groups. In Sj?gren syndrome, a significant difference in the fractal dimension was observed between the subgroup having punctuate fillings with a diameter less than 1 mm and the subgroup from 1 to 2 mm (P < .001). CONCLUSION. The fractal dimension is useful as a numeric grading of the complexity of the ductal pattern and the progression of parotid disease.  相似文献   
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