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71.
In order to develop new anti-inflammatory agents having different action mechanisms compared with nonsteroidal and steroidal anti-inflammatory drugs, the culture broths of various actinomycetes isolated from soil were screened using anin vivo mouse ear edma assay and one strain (Streptomyces sp. MT 2705-4: KCTC 8651P) was selected. Activity-guided purification led to the isolation of a polyether compound, dianemycin. Topically, dianemycin showed a potent anti-inflammatory activity in mouse ear edema induced by croton-oil or arachidonic acid. ED(50) value of dianemycin was found to be 0.8 mg/ear compared to 0.4 mg/ear of prednisolone in croton-oil ear edema. However, dianemycin did not show the inhibitory activity in UV-erythema and delayed hypersensitivity reaction. These results indicate that dianemycin is a potential topical anti-inflammatory agent. 相似文献
72.
We present results from a simulation study for the estimation of a common odds ratio in multiple 2 × 2 tables when the data are correlated within clusters. We model the correlation of the data by the beta-binomial distribution. Through a simulation study, we compare the Mantel—Haenszel estimator with Rao and Scott'S estimator in terms of their biases, observed variances, relative efficiencies of their variances and 95 per cent coverage proportions. We limit the simulation study to the case where there are the same number of subjects in each cluster and the same number of observations in each row of each stratum. When ρ = 0, we recommend use of the Mantel—Haenszel estimator γMH with an unadjusted variance and Rao and Scott'S estimator γ with a pooled design effect. In general, when ρ >0, we recommend the Mantel—Haenszel estimator γMH with an adjusted variance and Rao and Scott'S estimator γ with a pooled design effect. 相似文献
73.
Ahn YK Park JC Park WS Kim NH Kim JW Kim SH Cho JH Jeong MH Cho JG Kang JC 《Journal of Korean medical science》1999,14(5):571-574
Epicardial fat may anteriorly produce an echo-free space that can be mistaken for pericardial fluid. We recently experienced a 67-year-old woman with prominent epicardial fat which was presented as an echogenic tumor-like mass. She underwent open pericardiostomy to relieve large amount of pericardial effusion. Operative findings revealed only prominent epicardial fat. Biopsy of the pericardial and fat tissues revealed an inflammation and normal fat cells without any malignant cell infiltration. 相似文献
74.
Torry DS Ahn H Barnes EL Torry RJ 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,41(1):79-85
PROBLEM: In spite of the known requirement for adequate vascularity during placentation, little is known regarding the regulation of angiogenic growth factor production by trophoblast. Placenta growth factor (PIGF) is a recently discovered angiogenic growth factor whose expression is relatively limited to trophoblast. METHOD OF STUDY: Current literature of PIGF was reviewed, with emphasis on its expression, regulation, role in angiogenesis, and potential function(s) at the maternal-fetal interface. RESULTS: PIGF is abundantly expressed by trophoblast, which implies that it could act in a paracrine manner to modulate vascular development, stability, and/or function within the decidua and placental villi. In addition, expression of the PIGF receptor, fms-like tyrosine kinase (flt-1) receptor, on trophoblast raises the potential for an autocrine role of PIGF in regulating trophoblast growth and/or function. CONCLUSIONS: The potential for PIGF to influence both vascular endothelial cells and trophoblast suggests that aberrant trophoblast production of PIGF could compromise cellular function during gestation and contribute to the vascular and placental pathologies noted in many obstetric complications. 相似文献
75.
Bone marrow edema and associated pain in early stage osteonecrosis of the femoral head: prospective study with serial MR images 总被引:31,自引:0,他引:31
PURPOSE: To determine the accuracy of magnetic resonance (MR) cholangiography for demonstration of the biliary tract and detection of biliary complications in patients who have undergone orthotopic liver transplantation. MATERIALS AND METHODS: Breath-hold half-Fourier rapid acquisition with relaxation enhancement MR cholangiography was performed in 25 patients who had undergone orthotopic liver transplantation. MR cholangiograms were prospectively and independently interpreted by two radiologists for depiction of the biliary tract and ductal anastomosis and for complications (eg, biliary dilatation, stricture, stones). MR cholangiographic findings were correlated with findings from direct cholangiography (n = 24) and surgery (n = 1). RESULTS: MR cholangiography completely demonstrated first-order intrahepatic bile ducts in 23 (92%) patients, the donor extrahepatic bile duct in 25 (100%), the recipient extrahepatic bile duct in 17 of 18 (94%), and the anastomosis in 24 (96%). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of biliary dilatation and stricture were each 100%. Complete interobserver agreement occurred in the detection of biliary dilatation and stricture. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of stones were 100% for one radiologist and 86%, 100%, 96%, 100%, and 95%, respectively, for the other. Both radiologists agreed on the diagnosis of bile duct stones in six of seven cases (kappa = 0.90). CONCLUSION: MR cholangiography enables accurate depiction of the biliary tract and detection of biliary complications in patients with an orthotopic liver transplant. 相似文献
76.
BACKGROUND: The most common neoplasm of the parotid gland is the pleomorphic adenoma. The familial occurrence of such tumors arising within the parotid gland is rare, with only 3 previous reports in the literature. Bilateral synchronous pleomorphic adenomas of the parotid gland are also uncommon. We report 2 siblings with pleomorphic adenomas of the parotid gland, 1 of whom had bilateral synchronous mixed tumors. Patients and Methods Chromosomal analysis of tumor cells from the sibling with bilateral adenomas revealed the translocation t(3;12)(p21;q15). Chromosome 12q breakpoints have previously been identified in a wide variety of solid tumors including pleomorphic adenomas of the parotid gland. CONCLUSIONS: We discuss bilateral mixed tumors, familial parotid tumors, and the potential for a genetic predisposition for the recurrence of such parotid tumors, as suggested by characteristic chromosomal translocations associated with mixed tumors. 相似文献
77.
D S Kim M S Lee D H Kim J M Bae M H Shin C M Lee H W Koo W Kang Y O Ahn 《Journal of epidemiology / Japan Epidemiological Association》1999,9(3):146-154
Since the completeness of case ascertainment is directly related to the validity of a study, the evaluation of completeness is an essential feature of a cohort study. To estimate the completeness of cancer case ascertainment during a three year period (Jan. 1, 1993, to Dec. 31, 1995) in which the Seoul Male Cohort was followed up, we applied capture-recapture method. Data were obtained from the cancer registries, medical records and death certificates, with cases identified from each source numbering 103, 105, and 38, respectively. After eliminating duplicate cases, the total number was 141, and by using a log-linear model, the number of cases not detected by any of the three data sources was estimated to be 16. For all cancers, the estimated completeness of follow-up was 89.9%. 相似文献
78.
79.
Chronic exposure to cadmium results in proteinuria. To gain insights into the mechanism by which cadmium inhibits the protein transport in the renal proximal tubule, we investigated the effects of cadmium on the receptor-mediated endocytosis of albumin, using fluorescein isothiocyanate-labeled bovine serum albumin (FITC-albumin) as a model substrate and opossum kidney cell line (OK cell) as a proximal tubular cell model. Cell monolayers grown to confluence were treated with 100 microM CdCl(2) for 60 min at 37 degrees C, washed, and tested for FITC-albumin uptake (37 degrees C) and surface binding (4 degrees C). The amounts of FITC-albumin uptake and binding were quantified by fluorimetrically determining the cell-adherent fluorescence. Both the binding and uptake of FITC-albumin by OK cells appeared to be saturable and inhibitable by unlabeled albumin in the medium, indicating that specific receptor sites were involved. The uptake of FITC-albumin was inhibited by agents that interfere with the formation of endocytotic vesicle (hypertonic mannitol), endosomal acidification (NH(4)Cl), and vesicular trafficking (cytochalasin D and nocodazole), confirming that the uptake occurred via the process of receptor-mediated endocytosis. In cells treated with cadmium, the specific FITC-albumin uptake was significantly attenuated, and this was due to a reduction in V(max) and a rise in K(m). These changes in kinetic parameters were similar to those induced by NH(4)Cl. The binding of FITC-albumin to the apical surface of OK cells was inhibited by cadmium treatment, and this was attributed to a reduction in B(max). The values of K(d) and its pH dependency were not altered by cadmium treatment. The formation of endocytotic vesicles, as judged by fluid phase endocytosis of FITC-inulin, was not changed by cadmium treatment. These results indicate that the receptor-mediated endocytosis of albumin is impaired in cadmium-treated OK cells most likely due to a defect in endosomal acidification and the attendant fall in ligand-receptor dissociation, which impairs receptor recycling and the overall efficiency of endocytosis. 相似文献
80.
Activation of NF-kappaB/Rel in angelan-stimulated macrophages. 总被引:3,自引:0,他引:3