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961.
Baum L Chan WM Li WY Lam DS Wang PB Pang CP 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》2003,217(2):111-114
ABCA4 gene sequence alterations cause Stargardt's disease (STGD) and may cause some age-related macular degeneration (AMD). We sought to shed light on these associations among Hong Kong Chinese by genotyping 140 AMD, 18 STGD and 95 normal control subjects for 15 ABCA4 exons which were reported to often contain AMD- or STGD-associated mutations. Sequence alterations R212H, T1428M, V1433I, T1572M, I2166M, IVS6-5T>G and IVS33+1G>T were found in AMD patients. T1428M and R2040X occurred in STGD patients. Control subjects displayed all the above missense alterations but no splicing or nonsense changes. Therefore, ABCA4 splicing mutations may be associated with a small proportion of AMD cases. 相似文献
962.
Robinson MR Lee SS Sneller MC Lerner R Langford CA Talar-Williams C Cox TA Chan CC Smith JA 《Ophthalmology》2003,110(9):1770-1780
OBJECTIVE: To describe the clinical characteristics of tarsal-conjunctival disease in a cohort of patients with Wegener's granulomatosis (WG). DESIGN: Retrospective, case-controlled study. PARTICIPANTS: The medical records of 82 consecutive WG patients who underwent an eye examination between January 1996 and June 2002 at the National Institutes of Health were reviewed. METHODS: Details of the ophthalmic examination, results of medical therapy, and histopathologic analysis results were recorded. Tarsal-conjunctival disease was defined by (1). conjunctival hyperemia and granuloma formation, areas of necrosis, or active fibrovascular changes in the tarsus or conjunctiva, or (2). evidence of inactive fibrovascular scar. The association of tarsal-conjunctival disease with major organ system involvement was assessed using Bayesian methods. MAIN OUTCOME MEASURES: The occurrence and clinical characteristics of tarsal-conjunctival disease in a cohort of patients with WG and associations with major organ system involvement. RESULTS: Tarsal-conjunctival disease occurred in 13 of 82 patients (16%) with WG examined over a 6.5-year period. The palpebral surface of the upper lid was involved most commonly, showing conjunctival hyperemia in seven patients, granulomatous lesions in three patients, tarsal-conjunctival necrosis in four patients, active fibrovascular proliferation in six patients, and inactive fibrous scar tissue in seven patients. Histopathologic analysis of eyelid biopsy specimens showed granulomatous inflammation, focal necrosis, and areas of occlusive vasculitis in the tarsus and conjunctiva. In reviewing the patterns of organ involvement in patients with and without tarsal-conjunctival disease, the association of subglottic stenosis and nasolacrimal duct obstruction with tarsal-conjunctival disease showed a high probability of clinical significance. CONCLUSIONS: Tarsal-conjunctival disease, a previously uncommon finding in patients with WG, was characterized by inflammation of the palpebral conjunctiva and tarsus followed by a fibrovascular proliferation and scar formation. Because of the important association of tarsal-conjunctival disease with subglottic stenosis, which can progress and lead to laryngeal obstruction and respiratory failure, patients with tarsal-conjunctival disease should be referred to an otolaryngologist for evaluation. 相似文献
963.
Metabotropic glutamate (mGlu) receptors are involved in several forms of synaptic plasticity in the rat hippocampus. Agonists which activate group I mGlu receptors induce slow-onset potentiation without prior tetanization in the hippocampal area CA1. Activation of group I mGlu receptors induces protein synthesis which may contribute to mGlu receptor-dependent forms of long-term plasticity. Calcium-binding proteins are widely considered to comprise key elements for synaptic plasticity. Therefore, we investigated whether the calcium sensor protein VILIP-1 is associated with group I mGlu receptor-mediated plasticity in the dentate gyrus (DG) in vivo.Application of either the group I and II mGlu agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylate (ACPD) or the selective group I agonist (R,S)-3,5-dihydroxyphenylglycine (DHPG) resulted in slow-onset potentiation in the DG of adult rats. In hippocampal cell cultures both agonists elicited an enhanced expression of VILIP-1. In situ hybridization revealed strong hippocampal expression of VILIP-1 and intracerebral application of DHPG to adult rats significantly enhanced hippocampal VILIP-1 expression. The DHPG effects in both, hippocampal cultures and in vivo, were prevented by the group I mGlu receptor antagonist 4-Carboxyphenylglycine (4CPG).Calcium sensor proteins thus appear to be regulated by mGlu receptors in an activity-dependent manner. A specific role for group I mGlu receptors is evident. Furthermore, the sensor proteins may function as molecular switches for the long-term regulation of synaptic plasticity. 相似文献
964.
A polymeric micelle drug delivery system was developed to enhance the solubility of poorly-water soluble drug, biphenyl dimethyl dicarboxylate, DDB. The block copolymers consisting of poly(D,L-lactide) (PLA) as the hydrophobic segment and methoxy poly(ethylene glycol) (mPEG) as the hydrophilic segment were synthesized and characterized by NMR, DSC and MALDI-TOF mass spectroscopy. The size of the polymeric micelles measured by dynamic light scattering showed a narrow monodisperse size distribution with the average diameter less than 50 nm. The MW of mPEG-PLA, 3000 (MW of mPEG, 2 K; MW of PLA, 1 K), and the presence of hydrophilic and hydrophobic segments on the polymeric micelles were confirmed by MALDI-TOF mass spectroscopy and NMR, respectively. Polymeric micelle solutions of DDB were prepared by three different methods, i.e. the matrix method, emulsion method and dialy-sis method. In the matrix method, DDB solubility was reached to 13.29 mg/mL. The mPEG-PLA 2K-1 K micelle system was compared with the poloxamer 407 micelle system for their critical micelle concentration, micelle size, solubilizing capacity, stability in dilution and physical state. DDB loaded-polymeric micelles prepared by the matrix method showed a significantly increased aqueous solubility (>5000 fold over intrinsic solubility) and were found to be superior to the poloxamer 407 micelles as a drug carrier. 相似文献
965.
Synthesis and PGE<Subscript>2</Subscript> inhibitory activity of vinylated and allylated chrysin analogues 总被引:3,自引:0,他引:3
Vinylated and allylated chrysin analogues were prepared as congeners of prenylated flavonoids and evaluated their anti-inflammatory activity. 8-Substituted chrysin analogues were prepared from 2'-hydroxy-3'-iodo-4',6'-dimethoxyacetophenone in 3 steps. 3-Allylated chrysin analogues were prepared from chrysin in 3 steps. Synthesized chrysin analogues (4, 5 and 8) showed moderate inhibitory activities of PGE2 production from LPS-induced RAW 264.7 cells. 相似文献
966.
In this study, we sought to determine the globule size distribution of a propofol/lidocaine mixture as a function of lidocaine concentration and time elapsed after mixing in a standard formulation of propofol emulsion (Diprivan) and in a new formulation containing L-lysine to improve stability. The globule size was measured with a laser diffraction technique. The median diameter of the globule size in 20 mL of Diprivan immediately after the addition of 0, 10, 20, 30, 40, and 50 mg of lidocaine was similar to that of chylomicrons, ranging from 0.28 +/- 0.01 micro m to 0.30 +/- 0.02 micro m, over the whole range of lidocaine concentration. However, the maximum diameter increased slightly (from 0.97 +/- 0.01 micro m to 2.90 +/- 0.07 micro m) as the concentration of lidocaine increased. At 6 h after adding lidocaine, the maximum globule size had increased slightly (to 2.98 +/- 0.04 micro m) with 20 mg of lidocaine and increased considerably (to 51.76 +/- 0.62 micro m) when 30 mg of lidocaine was added. At 2 h after the addition of 50 mg of lidocaine, the maximum globule diameter had increased to 52.2 +/- 1.92 micro m. The maximum globule diameter in the propofol emulsion to which L-lysine was added as a stabilizer did not exceed 3.0 micro m even when the largest amount of lidocaine was added. This study demonstrated that when 30 mg of lidocaine was added to 20 mL of Diprivan and the solution was left for a period of time, the globule size increased. Its increase was minimized by the addition of L-lysine to the propofol emulsion. 相似文献
967.
Cheng YF Chen CL Jawan B Huang TL Chen TY Chen YS Wang CC de Villa V Wang SH Wah CK Chiang YC Eng HL Lee TY Goto S 《Transplantation》2003,76(2):353-357
BACKGROUND: Preoperative delineation of any vascular anomalies offers planning for possible alteration of surgical procedures, especially in pediatric recipients undergoing living-related liver transplantation. PURPOSE: We assess the efficacy of three-dimensional (3D) multislice computed tomography (CT) angiography in the hope of replacing conventional angiography as the pretransplant evaluation of the hepatic vascular system for potential recipients of liver transplantation. METHODS: 3D CT angiography was performed in 38 children with biliary atresia. Conventional angiography was also performed in the first 15 patients. Twelve patients underwent living-related liver transplantation. The findings on 3D CT angiography were compared with conventional angiography and operative findings. RESULTS: 3D CT angiography was successfully performed in 37 pediatric patients. All findings of 3D CT angiography on hepatic artery, portal vein, and inferior vena cava paralleled those of catheter angiography and operative findings. Four patients were unsuitable to receive living grafts because of pathologic insults of the hepatic artery (one patient) and the portal vein (three patients). Three patients were advised to undergo a venous graft for portal anastomoses. Eight patients demonstrated portosystemic shunts that may require closure. CONCLUSION: 3D CT angiography proves to be a better tool in the demonstration of the vascular system and identification of pathologic insults in pediatric patients. It is superior to conventional angiography because it is less invasive, more convenient, and more efficient in providing thorough preoperative information that would have a major impact on patient selection and surgical planning. 相似文献
968.
969.
A diamantane derivative 1,6-Bis [4-(4-amino-3-hydroxyphenoxy) phenyl] diamantane (DPD) was found to inhibit the growth of several cancer cell lines in the National Cancer Institute (NCI) Anticancer Drug Screen system. In this study, we examined the in vitro and in vivo effects of DPD on human colon cancer cells. DPD exerted growth inhibitory activities in vitro against three human colon cancer cell lines (Colo 205, HT-29, and HCT-15). DPD-treated cells were arrested at G(0)/G(1) as analysed by flow cytometric analysis. The expression of cyclin D was decreased in DPD-treated cells. The differentiation markers of carcinoembryonic antigen and fibronectin were significantly increased in colon cancer cells after treatment with DPD. The epithelium-like brush borders on HT-29 cell surface were also demonstrated at 1 week after withdrawal from DPD treatment. The DPD-induced cell growth inhibition and differentiation were irreversible after removal of DPD. The in vivo effect of tumour growth suppression by DPD was also observed in mouse xenografts. No acute toxicity was observed after an intraperitoneal challenge of DPD in BALB/c-nude mice weekly. These results suggest that DPD appears to be a new potentially less toxic modality of cancer therapy. 相似文献
970.
We analysed incidence data of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) of the skin from the Cancer Registry Saarland, Germany. During 1995-1999, the age-standardised incidence rates (world standard population) of BCC and SCC were 43.7 and 11.2 per 100000 among men and 31.7 and 4.4 per 100000 among women. 相似文献