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991.
Oliver R Segal Anthony W C Chow Vias Markides Richard J Schilling Nicholas S Peters D Wyn Davies 《Heart rhythm》2005,2(5):474-482
OBJECTIVES: The purpose of this study was to assess the long-term effects of ablation of infarct-related ventricular tachycardia (VT) and the subsequent requirement for implantable cardioverter-defibrillator (ICD) therapy. BACKGROUND: The long-term consequences after initially successful catheter ablation of infarct-related VT remain unclear. METHODS: Forty patients who presented with infarct-related VT were studied using noncontact mapping to guide ablation. RESULTS: One hundred forty VTs were mapped using the noncontact mapping system, including 36 (25.7%) clinical VTs. An endocardial exit site was determined in 100% of VT circuits, diastolic endocardial activity in 77 VTs (55%), and complete circuits in 24 VTs (17.1%). Eighty-one VTs (57.9%) were targeted for ablation, of which 67 (82.7% of targeted) were successfully ablated, including 27 clinical VTs (75% of clinical). Documented recurrence of an ablated VT occurred in 7.5% of patients over 36.3 +/- 21.0 months of follow-up. Episodes of new or recurrent, nontargeted VT or ventricular fibrillation (VF) occurred in 37.5% and VT recurrence without documentation of cycle length in 5%. In patients with ICDs, mean shock frequency was reduced from 6.8 +/- 7.3 per month in the year prior to ablation to 0.05 +/- 0.12 per month after ablation, over 24.7 +/- 18.9 months of follow-up (P < .0001). CONCLUSIONS: In patients with infarct-related VT, noncontact mapping-guided VT ablation is associated with a high procedural success rate, and VT recurrence necessitating ICD therapy delivery is significantly reduced. However, only 42.5% of patients remain free from VT/VF 3 years after ablation. Catheter ablation for infarct-related VT is indicated as an adjunctive therapy in patients with symptomatic VT but cannot substitute for ICDs and antiarrhythmic drugs. 相似文献
992.
The efficacy of cephalothin and cephaloridine in the treatment of bacterial meningitis was evaluated from a review of 106 cases reported in the literature. Fifty-nine percent of 34 patients treated with intravenous cephalothin responded suboptimally; those receiving daily doses of 12 g or more fared significantly better (P less than 0.025). In contrast, 74% of 72 patients treated with cephaloridine responded favorably; those who received concomitant intrathecal cephaloridine responded significantly better (P less than 0.005). These findings indicate that cephalosporin therapy for bacterial meningitis, without concomitant intrathecal medication, is unreliable and that this is probably due to inadequate penetration of the antibiotics into cerebrospinal fluid. In penicillin-allergic patients with pneumococcal, meningococcal, and hemophilus meningitis, chloramphenicol is the agent of choice. For staphylococcal meningitis, intravenous cephalothin at doses of 12 g/day with additional intrathecal cephaloridine at doses of 12.5 to 50 mg/day should be administered concomitantly. 相似文献
993.
994.
Macrophage migration inhibitory factor stimulated by Helicobacter pylori increases proliferation of gastric epithelial cells 总被引:1,自引:0,他引:1
Xia HH Lam SK Chan AO Lin MC Kung HF Ogura K Berg DE Wong BC 《World journal of gastroenterology : WJG》2005,11(13):1946-1950
AIM: Helicobacter pylori ( H pylorl) is associated with increased gastric inflammatory and epithelial expression of macrophage migration inhibitory factor (MIF) and gastric epithelial cell proliferation. This study aimed at determining whether H pyloridirectly stimulates release of MIF in monocytes, whether the cag pathogenicity island (PAI) is involved for this function, and whether MIF stimulated by H pylori increases gastric epithelial cell proliferation in vitro. METHODS: A cytotoxic wild-type Hpyloristrain (TN2), its three isogenic mutants (TN2Acag, TN2AcagA and TN2AcagE) were co-cultured with cells of a human monocyte cell line, THP-1, for 24 h at different organism/cell ratios. MIF in the supernatants was measured by an ELISA. Cells of a human gastric cancer cell line, MKN45, were then co-cultured with the supernatants, with and without monoclonal anti-MIF antibody for 24 h. The cells were further incubated for 12 h after addition of 3H-thymidine, and the levels of incorporation of 3H-thymidine were measured with a liquid scintillation counter. RESULTS: The wild-type strain and the isogenic mutants, TN2ΔcagA and TN2ΔcagE, increased MIF release at organism/cell ratios of 200/1 and 400/1, but not at the ratios of 50/1 and 100/1. However, the mutant TN2Δcag did not increase the release of MIF at any of the four ratios.^ 3H-thymidine readings for MKN-45 cells were significantly increased with supernatants derived from the wild-type strain and the mutants TN2ΔcagA and TN2ΔcagE, butnot from the mutant TN2A cag. Moreover, in the presence of monoclonal anti-MIF antibody, the stimulatory effects of the wild-type strain on cell proliferation disappeared. CONCLUSION: H pylori stimulates MIF release in monocytes, likely through its cag PAI, but not related to cagA or cagE. H pylori-stimulated monocyte culture supernatant increases gastric cell proliferation, which is blocked by anti-MIF antibody, suggesting that MIF plays an important role in H pylori-induced gastric epithelial cell proliferation. 相似文献
995.
OBJECTIVE: To evaluate the effect of 1alpha-hydroxyvitamin D3 on bone mineral density of the lumbar spine in postmenopausal women receiving hormone replacement therapy and calcium supplement. DESIGN: A randomized, prospective 2-year clinical trial. PATIENTS AND MEASUREMENTS: A total of 240 postmenopausal women were enrolled with randomized assignment of 120 patients to each treatment group (the D + E group of 1alpha-hydroxyvitamin D3 + sequential combined HRT + calcium supplement; the E group: sequential combined HRT + calcium supplement). None of the patients had received HRT for menopausal syndrome or osteoporosis before being enrolled in our study. Serum biochemical assays, electrolytes and calcitonin were performed at baseline and after 6 and 12 months of treatment. Bone mineral density (BMD) of L2-L4 was measured by dual energy X-ray absorptiometry (DXA) at the initial assessment and after 12 and 24 months of treatment. RESULTS: One hundred and five patients (87.5%) in the D + E group and 92 patients (76.7%) in the E group completed the first 1-year study. Ninety-six patients (80%) in the D + E group and 80 patients (66.7%) in the E group completed the 2-year trial. Renal function, liver function, electrolytes and calcitonin showed no significant changes during the first year of follow-up. In the D + E group, the BMD of L2-4 increased 3.24 +/- 0.32% from baseline after 1 year (P < 0.05) and 5.32 +/- 0.23% after 2 years of treatment (P < 0.05). On the other hand, the changes of BMD in the E group were 1.12 +/- 0.34% after 1 year (P < 0.05) and 2.42 +/- 0.26% after 2 years of treatment (P < 0.05). The changes of BMD of L2-L4 of the D + E group were higher than the changes of the E group after both 1 and 2 years of treatment (P < 0.05). CONCLUSIONS: Our study demonstrated that combination of 1alpha-hydroxyvitamin D3 with HRT is superior to HRT alone for the preservation of bone mineral density in postmenopausal women under calcium supplementation. 相似文献
996.
A brief report on the normal range of forehead temperature as determined by noncontact, handheld, infrared thermometer 总被引:1,自引:0,他引:1
Ng DK Chan CH Chan EY Kwok KL Chow PY Lau WF Ho JC 《American journal of infection control》2005,33(4):227-229
BACKGROUND: Noncontact forehead temperature measurement by handheld infrared thermometer was used as a screening tool for fever. However, the accuracy data and normal range of forehead temperature determined by this method were not available. METHODS: The temperature readings from 3 handheld infrared thermometers were validated against an electronic thermometer. Normal range of forehead temperature was determined by measuring the forehead temperature in 1000 apparently healthy subjects. RESULTS: Significant differences were detected in readings obtained by the 3 different handheld infrared thermometers (analysis of covariance, P < .001) The most accurate one was chosen, and the normal range of forehead temperature in 1000 subjects detected by this method was 31.0 degrees C to 35.6 degrees C. CONCLUSIONS: Our study shows that commercially available, handheld infrared thermometers require individual validation. Forehead temperature in excess of 35.6 degrees C is suggestive of fever. Further studies are required to confirm accuracy of this value in detecting fever. 相似文献
997.
J J Lipka I Miyoshi K G Hadlock G R Reyes T P Chow W A Blattner G M Shaw C V Hanson D Gallo L Chan 《The Journal of infectious diseases》1992,165(2):268-272
A recombinant protein of the human T cell lymphotropic virus type I (HTLV-I) gp46 outer membrane envelope, MTA-4 (residues 129-203), reacted by Western blot with sera from HTLV-I-infected individuals from the United States and Jamaica but not with 24 (10%) of 242 Japanese sera. A related gp46 recombinant protein, MTA-1 (residues 162-209), reacted with all 58 sera from HTLV-I-infected US and Jamaican individuals and 238 of 242 sera from infected Japanese (combined sensitivity of 99%). Neither recombinant showed reactivity to sera from HTLV-II-infected individuals or uninfected controls. The reactivity of recombinant proteins containing the region of HTLV-II gp46 analogous to MTA-1 was also evaluated by Western blot: GH2-K15 (residues 157-205) and GH2-K55 (residues 162-205) reacted with 88 (98%) and 89 (99%), respectively, of 90 sera from HTLV-II-infected individuals but not with sera from HTLV-I-infected individuals or uninfected controls. These recombinant proteins should permit the development of assays to unambiguously confirm and differentiate HTLV-I and HTLV-II infections. 相似文献
998.
Transcatheter closure of patent ductus arteriosus in Chinese adults: immediate and long-term results
Lee CH Leung YL Kwong NP Kwok OH Yip AS Chow WH 《The Journal of invasive cardiology》2003,15(1):26-30
BACKGROUND: Transcatheter closure of patent ductus arteriosus (PDA) has been established as a safe and effective treatment for pediatric patients. However, long-term experience in adults remains limited. Therefore, our purpose is to report our experience with this approach in Chinese adults. METHODS: Twenty-five patients (mean age, 34 years) who underwent transcatheter closure of PDA in a tertiary cardiology center in Hong Kong were recruited. RESULTS: The mean PDA diameter measured by angiogram was 3.1 mm (range, 1.3 6.6 mm) and the mean pulmonary-to-systemic shunt was 1.65 (range, 1.3 1.8). All procedures were performed under local anesthesia. The average procedure and fluoroscopy times were 54 14 minutes and 14 4 minutes, respectively. The mean period of hospitalization was 4 days (range, 3 5 days). Immediate, one-month and late success rates were 96%, 92% and 84%, respectively. CONCLUSIONS: Percutaneous closure of PDA in adults is a safe and feasible procedure. It should be a reasonable alternative for adult patients who are either not fit for open-chest surgery or who prefer a less invasive approach. 相似文献
999.
Two cases of lung abscess, in which Legionella species were identified in association with other bacterial isolates, are presented. In the first case, Legionella pneumophila and Klebsiella pneumoniae were identified in a 24-year-old post renal transplant patient with a right upper lobe pulmonary abscess. Healing did not occur until the institution of specific therapy directed against legionella. In the second case, Legionella micdadei and several other respiratory bacterial pathogens were identified in a 74-year-old woman with a lung abscess. The patient later died with multisystem failure despite adequate antimicrobial therapy. Prior cases of legionella-associated lung abscess have occurred predominantly in corticosteroid-treated patients. The role of coexisting bacterial isolates remains obscure. 相似文献
1000.
Tan CK Chow PK Findlay M Wong C Machin D 《Journal of gastroenterology and hepatology》2000,15(7):725-729
Hepatocellular carcinoma is often diagnosed at a late, inoperable stage for which there are no uniformly efficacious treatment available presently. The oral anti-oestrogen drug, tamoxifen, has been used in such patients, based on the belief that the growth of hepatocellular carcinoma is promoted by endogenous oestrogen via a receptor-mediated process. In this review, we examine the trials reported in the literature using tamoxifen in hepatocellular carcinoma. Randomized controlled trials with tamoxifen have so far revealed mixed results. We propose that this may be due to the fact that the mechanism of action of tamoxifen in hepatocellular carcinoma is via an oestrogen-receptor independent pathway that requires much higher doses of tamoxifen for activation than those used in the trials so far. Thus there must be a paradigm shift to dissociate the action of tamoxifen from oestrogen receptors in hepatocellular carcinoma. This means that future trials with tamoxifen in hepatocellular carcinoma should use higher doses of tamoxifen, at least four to eight-fold that of the dose that is efficacious in an oestrogen-receptor dependent mechanism. 相似文献