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81.
OBJECTIVE: To study the surgical outcome and complications of Ahmed glaucoma valve (AGV) implantation with mitomycin C (MMC) in refractory glaucoma. PATIENTS AND METHODS: The authors retrospectively reviewed the records of 40 eyes in 37 consecutive patients who underwent combined AGV with MMC (0.4 mg/mL; 5 minutes). All patients had a minimum of 6 months of follow-up. Outcome measures were best corrected visual acuity, intraocular pressure (IOP), the number of medications, success rates, and the incidence of complications. RESULTS: The Kaplan-Meier life table analysis revealed that the probabilities of surgical success based on our success criteria at 1 year and 2 years postoperatively were 80% and 77%, respectively. Postoperative IOP was significantly lower at all follow-up intervals. At the final visit fewer glaucoma medications were used (2.5 vs 0.7, preoperative vs postoperative). The most frequent complication was hypotony (17%). CONCLUSION: In this retrospective case series with relatively short follow-ups, AGV implantation with mitomycin C in refractory glaucoma appears to be effective without increased complication rates.  相似文献   
82.
Unilateral pulmonary vein atresia: Clinical and radiographic spectrum   总被引:1,自引:1,他引:1  
Three cases of unilateral pulmonary vein atresia are presented to illustrate part of the clinical and radiographic spectrum of this anomaly. One patient had major associated cardiovascular abnormalities and pulmonary hypertension, one had recurrent hemoptysis, and the other patient was asymptomatic with normal pulmonary artery pressure and no associated abnormalities. In one case, serial catheterizations indicated that the pulmonary vein atresia was acquired. This report stresses the radiographic, hemodynamic, and angiographic findings in patients with unilateral severe pulmonary venous obstruction. The embryology, pathology, and surgical approach are also discussed. The diagnosis should be strongly suspected before cardiac catheterization when typical features are present on the chest radiograph and isotopic ventilation perfusion scan.  相似文献   
83.
Background/Purpose: This study was conducted to evaluate the role of laparoscopic surgery in the treatment of gallbladder cancer. Methods: A retrospective study was performed on 31 patients with a postoperative diagnosis of gallbladder cancer. The laparoscopic approach was initially applied to all of them. Results: Ten patients had a pT1a cancer, and all underwent laparoscopic cholecystectomy without recurrence. Nine patients had pT1b lesions, and three had to be converted to an open operation. There were two recurrences. In one of the converted patients the cystic node was invaded. Seven patients had a pT2 lesion, and in four of them the operation was converted to an open procedure. Recurrences were noted in three patients. In two patients with pT3 cancer, the opera-tions were converted; both cancers recurred. Only diagnostic laparoscopy or a palliative laparoscopic procedure was performed for pT4 cancers. The median follow-up time was 17.0 months. The 5-years survival rate was 100% for patients with stage pT1a, 100% for pT1b, and 68% for pT2 lesions. Conclusions: We suggest that when a polypoid lesion of the gallbladder is found on preoperative evaluation, laparoscopic surgery may be attempted initially. During the procedure it is important to open all specimens when a polypoid lesion is present and perform a frozen section biopsy. When a pT1a lesion is found, laparoscopic cholecystectomy is sufficient; however, when a pT1b or more advanced lesion is found, the operation might be converted to a radical cholecystectomy. Received: July 2, 2002 / Accepted: July 2, 2002 Offprint requests to: E.K. Kim  相似文献   
84.
Lee JW  Roh TC  Rho MC  Kim YK  Lee HS 《Planta medica》2002,68(10):891-895
The CHCl(3) -soluble fraction obtained from the MeOH extract of Peucedanum japonicum Thunb. inhibited phenylephrine-induced vasoconstriction in isolated rat thoracic aorta. We isolated a vasorelaxing compound, as one of the bioactive components, which was identified as (+)- cis-4'- O-acetyl-3'- O-angeloylkhellactone (1), a pyranocoumarin, and examined the mechanisms of vasorelaxant effect caused by 1. This compound (1) (10(-6)-10(-4) M) concentration-dependently relaxed the isolated rat thoracic aorta pre-contracted with phenylephrine (PE). This vasorelaxant potency was diminished by endothelial removal (by 20%), L- N(G)-nitro-arginine or methylene blue (MB), but not indomethacin treatment. These findings indicate that the vasorelaxant effect of 1 was partially endothelium dependent and mediated by nitric oxide and cyclic GMP pathway. To determine if the effect of 1 was mediated through the activation of some of the receptors known to lead to vascular relaxation, the effects of atropine, triprolidine and propranolol were determined. 1-induced vasorelaxation was not affected by atropine, triprolidine and propranolol. Compound 1 inhibited high potassium (80 mM)-induced, calcium-dependent contractions in a concentration-dependent manner. But it slightly relaxed the rat aorta precontracted with PE in the presence of nifedipine, a blocker of voltage-operated calcium channels. Tetraethylammonium (TEA, a non-specific (K+) channel blocker) did not affect the vasodilatory effect of 1 against PE-induced contraction. Mechanisms of the vasorelaxant effect of 1 were multiple, including endothelium dependence and Ca(2+) channel blockade.  相似文献   
85.
The inhibitory activity of tanshinones from Salvia miltiorrhiza was tested on rat liver diacylglycerol acyltransferase (DGAT). Cryptotanshinone (1) and 15,16-dihydrotanshinone I (3) exhibited potent DGAT inhibitory activities dose-dependently with IC50 values of 10.5 microg/ml and 11.1 microg/ml. However, tanshinone IIA (2) and tanshinone I (4) showed very weak inhibition (IC50 value: > 250 microg/ml). A dihydrofuran moiety was seemed to be responsible for the stronger inhibitory activity.  相似文献   
86.
BACKGROUND: We have been using hybrid total hip arthroplasty (a cementless acetabular component and a cemented stem) in young patients. The purpose of this study was to determine the prevalence of aseptic loosening, polyethylene wear, and osteolysis after the use of this technique. METHODS: We studied a prospective consecutive series of sixty-four primary hybrid total hip replacements in fifty-five patients younger than fifty years old. There were forty-three men and twelve women; the average age at the time of the index operation was 43.4 years. The average duration of follow-up was 9.4 years. We used a cementless acetabular component without screw-holes and a cemented femoral component with a 22-mm head in all hips. Clinical follow-up with use of Harris hip ratings and radiographic follow-up were performed at six weeks; at three, six, and twelve months; and yearly thereafter. The sequential annual linear and volumetric wear rates were measured, and bone-remodeling and osteolysis were assessed. RESULTS: The mean preoperative Harris hip score was 44 points, which increased to 95 points at the time of final follow-up. No hip had aseptic loosening. One hip (2%) was revised because of late infection. The average linear wear (and standard deviation) was 0.96 +/- 0.066 mm, with an average annual rate of 0.096 +/- 0.013 mm. The average volumetric wear was 364.7 +/- 25.2 mm (3), with an average annual rate of 43.4 +/- 3.5 mm (3). Six hips (9%) had an osteolytic lesion of <1 cm in diameter in the calcar femorale (zone 7). CONCLUSIONS: Our results show that a hybrid arthroplasty with a cementless acetabular component and a smooth cemented femoral component (Ra, 0.6 mm) is effective for primary total hip replacement in young patients. Although there was no aseptic loosening and a low prevalence of osteolysis at the latest follow-up evaluation, the high rates of linear and volumetric wear of the polyethylene liner in these young patients remain a concern.  相似文献   
87.
The inhibitors of prostaglandin biosynthesis and nitric oxide production have been considered as potential anti-inflammatory and cancer chemopreventive agents. In this study, we evaluated approximately 170 methanol extracts of natural products including Korean herbal medicines for the inhibition of prostaglandin E(2) production (for COX-2 inhibitors) and nitric oxide formation (for iNOS inhibitors) in lipopolysaccharide (LPS)-induced mouse macrophages RAW264.7 cells. As a result, several extracts such as Aristolochia debilis, Cinnamomum cassia, Cinnamomum loureirii, Curcuma zedoaria, Eugenia caryophyllata, Pterocarpus santalius, Rehmania glutinosa and Tribulus terrestris showed potent inhibition of COX-2 activity (>80% inhibition at the test concentration of 10 micro g/ml). In addition, the extracts of A. debilis, Caesalpinia sappan, Curcuma longa, C. zedoaria, Daphne genkwa and Morus alba were also considered as potential inhibitors of iNOS activity (>70% inhibition at the test concentration of 10 micro g/ml). These active extracts mediating COX-2 and iNOS inhibitory activities are warranted for further elucidation of active principles for development of new cancer chemopreventive and/or anti-inflammatory agents.  相似文献   
88.
Kang TC  Park SK  Hwang IK  An SJ  Bahn JH  Kim DW  Choi SY  Kwon OS  Baek NI  Lee HY  Won MH 《Brain research》2002,957(2):242-250
To identify the roles of pyridoxal kinase (PLK) in epileptogenesis and the recovery mechanisms in spontaneous seizure, a chronological and comparative analysis of PLK expression in the gerbil hippocampus was conducted. PLK immunoreactivity in a pre-seizure group of seizure sensitive (SS) gerbils was more strongly detected than that in a seizure resistant (SR) group. The density of PLK immunoreactivity in a 30-min postictal group was significantly lower than that of a pre-seizure group. In a 12 h postictal group, PLK immunodensity recovered to pre-seizure level. The over-expression of PLK in the hippocampus of pre-seizure SS gerbils suggests that PLP play an important role in the modulation of GAD activity and GABA reuptake as mediated by membrane transporter via neurons.  相似文献   
89.
The aim of this study was to evaluate the efficacy of 0.005% latanoprost in lowering intraocular pressure (IOP) in patients with chronic angle-closure glaucoma (CACG) and no visible ciliary-body face. Fourteen eyes of 14 Korean patients with CACG with 360 degrees of peripheral anterior synechiae (PAS) and an IOP greater than 21 mmHg without medication were treated with 0.005% latanoprost once-daily. All patients completed 3 months of treatment with latanoprost. The IOP, which was 30.3 +/- 4.5 (mean +/- standard deviation) mmHg at baseline, decreased to 22.6 +/- 4.9 mmHg after 1 week, 19.6 +/- 5.5 mmHg after 1 month, 19.4 +/- 4.9 mmHg after 2 months, and 21.5 +/- 5.9 mmHg after 3 months of treatment with latanoprost (P < 0.01 for each). Ultrasound biomicroscopy of the anterior chamber angle showed anterior bowing of the iris with total occlusion of the angle by PAS, except for 5 eyes with focal microscopic openings to the ciliary-body face at various angles. Adverse ocular events were well-tolerated and transient. In this preliminary study, treatment with 0.005% latanoprost once-daily resulted in a significant reduction in IOP in CACG patients with 360 degrees of PAS on gonioscopy. Our results suggest that latanoprost may be considered as a therapy of choice in these rare cases.  相似文献   
90.
Interpretation of quantitative results of nerve fiber layer (NFL) thickness based on scanning laser polarimetry (GDx-NFA) can be quite challenging especially in glaucoma suspects. Purpose: Authors studied NFL parameters obtained from GDx-NFA in glaucoma suspects and compared them with those of patients with glaucoma Methods: Eighty six glaucoma suspects based on  相似文献   
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