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21.
OBJECTIVE AND DESIGN: The anti-inflammatory effect of myricetinglucuronide (MGL) was investigated and structurally-related compounds were compared to examine the structure/activity-relationship in carrageenan-induced rat paw edema. MATERIALS AND SUBJECTS: In vitro studies were performed using rat basophilic leukemia (RBL-1) cells, human polymorphonuclear leukocytes (PMNL), COX-1 from ram seminal vesicle, COX-2 from sheep placenta and human venous blood. For the in vivo tests male Wistar rats were used, for the ex vivo test perfused rabbit ears. TREATMENT: 1-300 microg/kg MGL or myricetinmethylglucuronate and 0.1-5 mg/kg other related compounds administered p.o. (carrageenan edema). 5, 50 and 150 microg/kg MGL p.o. for 14 days (Freund's adjuvant arthritis), 5 and 50 microg/kg p.o. for 6 days (ulceration). METHODS: Anti-inflammatory effects were measured in carrageenan edema and in adjuvant arthritis. Incidence of gastric lesions was tested in an ulcerogenicity model in vivo. Influence on COX was determined in the perfused rabbit ear, in PMNL and in a test assay using COX-1 and COX-2. 5-LOX activity was studied using PMNL and RBL-1. The influence on platelet aggregation was evaluated measuring light transmission. RESULTS: MGL exerted a marked and dose-dependent anti-inflammatory effect in acute (carrageenan edema, ED50 15 microg/kg, indomethacin ED50 10 mg/kg) and chronic (adjuvant arthritis, inhibition at 150 microg/kg 18.1 % left paw, 20.6% right paw, indomethacin 3 mg/kg 18.0% and 19.4%)) models of inflammation. In the perfused rabbit ear 1 microg MGL inhibited the release of PGI2, PGD2 and PGE2 to the same extent as 1 microg indomethacin. The inhibition of COX-1 in the intact cell system was IC50 = 0.5 microM, that of indomethacin 0.0038 microM. In the isolated enzyme preparations of COX-1 and COX-2 the IC50 was 10 microM and 8 microM, that of indomethacin 9.2 mM and 2.4 microM. In the RBL-1 and PMNL test assay the inhibition of 5-LOX was 0.1 microM and 2.2 microM. An orally administered dose of 50 microg/kg/day induced no gastric ulcers in rats treated for 6 days. The investigations on carrageenan edema showed a close relationship between the structure of MGL and the anti-inflammatory effect. CONCLUSIONS: MGL is a COX-1, COX-2 and 5-LOX inhibitor. In view of the moderate in vitro activity and the very potent in vivo activity an additive mechanism must be involved. Small changes in the molecular structure lead to the loss or reduction of the anti-inflammatory activity. 相似文献
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Of 101 women, 15-50 years of age, presenting with vaginal discharge, 34 had bacterial vaginosis and were randomly assigned to a seven-day course of oral treatment with either erythromycin (0.5 g b.i.d.) or metronidazole (0.4 g b.i.d.) in a single-blind, cross-over study. Treatment failure (> or = three clinical signs of bacterial vaginosis) occurred in 13 (81%) of 16 patients given erythromycin, as compared with three (17%) of 18 women treated with metronidazole (p < 0.001). Persistence of Gardnerella vaginalis, Mobiluncus species and/or Mycoplasma hominis was found in 14 of 16 patients treated with erythromycin, and in four of 16 patients treated with metronidazole. Treatment with metronidazole was successful (< or = two clinical signs of bacterial vaginosis) in eight of 10 cases of erythromycin treatment failure. Neither of two cases of metronidazole treatment failure was cured with erythromycin. At three-month follow-up of 31 women, persistence or recurrence of bacterial vaginosis was diagnosed in 11 cases (36%). 相似文献
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Resisting care is defined as any patient behavior which prevents or interferes with the care provider performing or assisting with ADLs for the patient, including bathing, eating, toileting, dressing and grooming. Significant consequences of resisting care include malnutrition, skin breakdown, dehydration, constipation and weight loss. Creativity, flexibility and patience are key components of any intervention. Due to the lability of the person with cognitive impairment, a plan that works perfectly one day may never work again. 相似文献
25.
Transformations for nonideal uniform circular arrays operating in correlated signal environments 总被引:2,自引:0,他引:2
Buon Kiong Lau Yee Hong Leung Yanqun Liu Kok Lay Teo 《Signal Processing, IEEE Transactions on》2006,54(1):34-48
The Davies transformation is a method to transform the steering vector of a uniform circular array (UCA) to one with Vandermonde form. As such, it allows techniques such as spatial smoothing for direction-of-arrival (DOA) estimation in a correlated signal environment, developed originally for uniform linear arrays, to be applied to UCAs. However, the Davies transformation can be highly sensitive to perturbations of the underlying array model. This paper presents a method for deriving a more robust transformation using optimization techniques. The effectiveness of the method is illustrated through a number of DOA estimation examples. 相似文献
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RM Bionta G Blewitt CB Bratton D Casper A Ciocio R Claus M Crouch ST Dye S Errede GW Foster W Gajewski KS Ganezer M Goldhaber TJ Haines TW Jones D Kielczewska WR Kropp JG Learned JM LoSecco J Matthews HS Park LR Price F Reines J Schulz S Seidel E Shumard D Sinclair HW Sobel JL Stone L Sulak R Svoboda G Thornton van der Velde JC C Wuest 《Canadian Metallurgical Quarterly》1987,36(1):30-36
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The change of foot length and width with age has been reported in a few anthropometric studies in the literature. However, the relationship with body height rarely is reported, and the dynamic effect of weightbearing on foot size has not been documented. In this series, 2829 children 3 to 18 years of age of equal gender distribution were included in the study. The foot length and width on weightbearing and nonweightbearing were measured with a special precision electronic caliper. The foot length and width were found to increase linearly from the age of 3 years until 12 years in girls and 15 years in boys. This was followed by a phase during which the increase plateaued. The foot length and width increased significantly on weightbearing at all ages in both genders with a mean of 2.1 to 4.4 mm or 3.1% to 4.8%, respectively. The foot length and width also were found to correlate significantly with the body height in both genders, with a correlation coefficient of 0.96 to 0.98. No significant differences were found between the sizes of the dominant and nondominant foot in either gender. 相似文献
30.
OFDM/FM frame synchronization for mobile radio data communication 总被引:13,自引:0,他引:13
A synchronization scheme enabling the use of orthogonal frequency division multiplexing (OFDM)/FM over a mobile radio channel in a pure ALOHA environment is proposed. The scheme encodes synchronization information in parallel with data in the same manner in which data is encoded in the OFDM/FM frame. The synchronization information is in the form of tones, centered in certain reserved frequency subchannels of the OFDM signal. The receiver uses a correlation detector, implemented in the frequency domain, to acquire synchronization accurately on a packet-by-packet basis. Experimental results indicate that the bit-error-rate performance achievable with the proposed scheme is within 1.5 dB of the performance obtained with ideal synchronization 相似文献