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41.
K S Leung W Y Shen H K Tsang K H Chiu P C Leung L K Hung 《The Journal of hand surgery》1990,15(1):11-17
One hundred cases of comminuted fracture of the distal radius were treated by a simple uniform method consisting of distraction by an external fixator for 3 weeks followed by functional bracing. During the application of the external fixator, autogenous cancellous bone chips were taken from the iliac crest and packed into the fracture site to realign the juxtaarticular fragments and to fill up the bone gap. Complications have been minimal. The results, after an average follow-up period of 20 months, taking into consideration subjective assessment of pain, objective measurement of wrist motion, and radiologic angles, have been excellent. 相似文献
42.
J. Lin W. Shiu W. T. Leung M. Tao N. Leung W. Y. Lau A. K. C. Li 《Cancer chemotherapy and pharmacology》1993,31(4):338-339
Summary A phase II study of high-dose ifosfamide in hepatocellular carcinoma was conducted among 17 Chinese patients. The dose of ifosfamide used was 2.5 g/m2 daily given as a continuous infusion for 5 days. In all, 15 patients were evaluable for tumour response. There was no complete or partial responder. The treatment was well tolerated. The most frequent toxicity was alopecia, which occurred in 11 patients, and 5 patients developed mild haematological toxicity. There was no evidence of liver or bladder toxicity. Overall, 14 patients were evaluable for survival. The median survival was 92 days (range, 30–568 days). We conclude that high-dose ifosfamide is well tolerated but ineffective in hepatocellular carcinoma in Chinese patients. 相似文献
43.
J. C. W. Mak H. C. M. Leung S. P. Ho F. W. S. Ko A. H. K. Cheung M. S. M. Ip M. M. W. Chan-Yeung 《Clinical and experimental allergy》2006,36(4):440-447
BACKGROUND: Reactive oxygen species may contribute to the pathogenesis of asthma. Functional genetic polymorphisms of antioxidant enzymes, superoxide dismutase (SOD) and catalase are good candidates for asthma susceptibility. OBJECTIVE: To investigate the association of the manganese-containing form of SOD (MnSOD) gene at amino acid position 16 (Val16Ala) and catalase gene in the promoter at A-21T and C-262T polymorphisms and asthma in a Hong Kong Chinese population. METHODS: The association study was conducted in a case-control design in asthma patients (n=251) and healthy controls (n=316) by genotyping. The functional significance was assessed by determining erythrocyte SOD and catalase activity. RESULTS: The Val allele of MnSOD at Val16Ala and the A allele of catalase gene at A-21T were not different between patients and controls, while the C allele of catalase gene at C-262T was found to be significantly different between patients and controls (P=0.033). The less frequent variant of catalase gene (-262T) was found to be protective from the development of asthma in a Hong Kong Chinese non-smoking population (adjusted odds ratio=0.35, 0.15-0.85; P=0.017). Asthma patients had elevated erythrocyte SOD and catalase activities in comparison with healthy controls (P<0.01). However, their activities were not associated with different genotypes within healthy controls or asthma patients. CONCLUSION: This is the first report showing that SOD and catalase functional activities are not associated with their respective genetic polymorphisms but related to the presence of asthma in a Hong Kong Chinese population. 相似文献
44.
Expression of beta-2-microglobulin by nasopharyngeal carcinoma. 总被引:1,自引:0,他引:1
Serum beta-2-microglobulin (beta 2M) levels of 274 Chinese patients with different stages of nasopharyngeal carcinoma at presentation and that of 35 patients who developed distant metastases post-treatment were assayed. beta 2M level was found to increase with advancing stage of disease, with statistically significant differences among early-stage, advanced-stage, and metastatic disease. Elevated pre-treatment beta 2M levels were expressed more frequently by tumours with lower degree of histological differentiation. The sensitivity of serum beta 2M for diagnosis of nasopharyngeal carcinoma, however, is low. 相似文献
45.
RS 39604: a potent, selective and orally active 5-HT4 receptor antagonist. 总被引:2,自引:0,他引:2 下载免费PDF全文
S. S. Hegde D. W. Bonhaus L. G. Johnson E. Leung R. D. Clark R. M. Eglen 《British journal of pharmacology》1995,115(6):1087-1095
1. Selective antagonism of 5-HT4 receptors may provide therapeutic benefit in certain disorders of the myocardium, alimentary and lower urinary tract. We now report on RS 39604, a novel and selective 5-HT4 receptor antagonist and compare its pharmacological properties with those of SB 204070. 2. In guinea-pig striatal membranes, both RS 39604 and SB 204070 inhibited specific binding of [3H]-GR 113808 in a concentration-dependent manner yielding pKi estimates of 9.1 and 10.9, respectively. RS 39604 displayed a low affinity (pKi < 6.5) for 5-HT1A, 5-HT2C, 5-HT3, alpha 1c, D1, D2, M1, M2, AT1, B1 and opioid mu receptors and moderate affinity for sigma 1, (pKi = 6.8) and sigma 2 (pKi = 7.8) sites. 3. In the rat isolated oesophagus, precontracted with carbachol, RS 39604 (30-300 nM) behaved as a competitive antagonist towards 5-HT-induced relaxation (pA2 = 9.3; Schild slope = 1.0). We and others have shown previously that SB 204070 behaves as an unsurmountable antagonist in this preparation (pA2 approximately 10.5). In the guinea-pig isolated ileal mucosa, RS 39604 (30 nM) antagonized 5-MeOT-induced increase in short-circuit current (pA2 = 9.1). 4. In anaesthetized vagotomized micropigs, RS 39604, administered by the i.v. or intraduodenal (i.duod.) route, produced dose-dependent inhibition of 5-HT-induced tachycardia (ID50 = 4.7 micrograms kg-1, i.v. and 254.5 micrograms kg-1, i.duod). At maximal doses of 30 micrograms kg-1, i.v. and 6 mg kg-1, i.duod., the inhibitory effects of RS 39604 lasted for more than 6 h.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
46.
M R Orford F C Leung G Milligan E D Saggerson 《Journal of the neurological sciences》1992,112(1-2):34-37
Treatment of rats for 3 days with T3 halved the abundance of the alpha-subunits of Gi1 and Gi2 in synaptosomal membranes isolated from the cerebral cortex. It is suggested that these changes could contribute to behavioural abnormalities in hyperthyroidism. Similar T3 treatment did not alter abundance of Gi1 alpha or Gi2 alpha in the medulla oblongata nor did it alter abundance of G(o) alpha-subunits in three tested brain regions. 相似文献
47.
D. MacDonald E. Lau E. L. P. Chan T. Mak J. Woo P. C. Leung R. Swaminathan 《Calcified tissue international》1992,51(6):412-414
Summary Serum intact parathyroid hormone (PTH), 25 hydroxyvitamin D(25OHD), 1,25 dihydroxyvitamin D (1,25(OH)2D), albumin, and ionized calcium were measured in 61 Chinese female patients with hip fracture and 61 control subjects. Hip fracture patients had low albumin, ionized calcium, and 250HD levels. Serum PTH and 1,25 (OH)2D values were not different between the two groups. We conclude that although 250HD level in hip fracture patients is low, there is no evidence of secondary hyperparathyroidism, suggesting that the low 250HD levels may be a secondary phenomenon in response to the fracture. 相似文献
48.
J D Helman J M Leung W H Bellows N Pineda G W Roach J D Reeves J Howse M T McEnany D T Mangano 《Anesthesiology》1992,77(1):47-62
Desflurane, a coronary vasodilator, may induce myocardial ischemia in patients with coronary artery disease. To determine whether desflurane is safe to administer to the at-risk patient population (with known coronary artery disease), we compared the incidence and characteristics of perioperative myocardial ischemia in 200 patients undergoing coronary artery bypass graft (CABG) surgery randomly assigned to receive desflurane (thiopental adjuvant) versus sufentanil anesthesia. Under conditions of hemodynamic control, perioperative ischemia was assessed using continuous echocardiography (precordial: during induction; transesophageal: during surgery) and Holter electrocardiography (ECG); hemodynamics (including pulmonary artery pressure) were measured continuously. Hemodynamic results: During induction, no significant changes in hemodynamics occurred in the sufentanil group, while in the desflurane group, heart rate, systemic and pulmonary arterial pressure increased and stroke volume decreased significantly. During the intraoperative period, the incidence of hemodynamic variations was low in both anesthetic groups; however, the prebypass incidence of tachycardia (greater than 120% of preoperative baseline heart rate) was greater in the desflurane group (4 +/- 7% of total time monitored) than in the sufentanil group (1 +/- 6%) (P = 0.0003). Similarly, the incidence of prebypass hypotension (less than 80% of preoperative baseline systolic arterial blood pressure) was greater in the desflurane group (21 +/- 14%) than in the sufentanil group (15 +/- 16%) (P = 0.01). ECG results: Preoperatively, 15% (28/191) of patients developed ECG ischemia, with no difference between patients who received desflurane, 13% (12/96) or sufentanil, 16% (16/95) (P = 0.6). During anesthetic induction, 9% (9/99) of patients who received desflurane developed ECG ischemia, compared with 0% (0/98) who received sufentanil (P = 0.007). During the prebypass period, 5% (10/197) of patients developed ECG ischemia, with no difference between patients who received desflurane, 7% (7/99) or sufentanil, 3% (3/98) (P = 0.3). Postbypass, 12% (24/194) of patients developed ECG ischemic changes, with no difference between patients who received desflurane, 13% (13/97) or sufentanil, 11% (11/96) (P = 0.9). Echocardiographic results: The incidence of precordial echocardiographic ischemia during anesthetic induction was 13% (5/39) in the desflurane group versus 0% (0/29) in the sufentanil group (P = 0.1). Moderate to severe transesophageal echocardiographic (TEE) ischemic episodes occurred in 12% (21/175) of patients during prebypass, with no significant difference between the desflurane group, 16% (15/91) and the sufentanil group, 7% (6/84) (P = 0.09). TEE ischemic episodes occurred in 27% (49/178) of patients during the postbypass period, with no difference between the desflurane, 29% (27/92) and sufentanil, 25% (22/86) groups (P = 0.7).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
49.
50.
Cefazolin plus ceftazidime versus imipenem/cilastatin monotherapy for treatment of CAPD peritonitis--a randomized controlled trial. 总被引:2,自引:0,他引:2
Chi-Bon Leung Cheuk-Chun Szeto Kai-Ming Chow Bonnie Ching-Ha Kwan Angela Yee-Moon Wang Siu-Fai Lui Philip Kam-Tao Li 《Peritoneal dialysis international》2004,24(5):440-446
BACKGROUND: Peritonitis is a serious complication of peritoneal dialysis (PD). We studied the efficacy of imipenem/cilastatin monotherapy in the treatment of PD-related peritonitis. METHODS: We performed an open-label, randomized control study comparing imipenem/cilastatin monotherapy (treatment group) versus cefazolin plus ceftazidime (control group) in the treatment of PD peritonitis. The result was further compared to a historic group treated with cefazolin plus netilmycin. Outcome measures were primary response rate at day 10 and complete cure rate. RESULTS: We enrolled 51 patients in the treatment group, 51 in the control group, and identified 96 in the historic group. The primary response rate to the assigned antibiotics was 49.0%, 51.0%, and 49.0% for the treatment, control, and historic groups, respectively (p = 0.97). The primary response rate allowing for change in antibiotic was 82.4%, 90.2%, and 82.3%, respectively, for the three groups (p = 0.41). The complete cure rate was 72.5%, 80.4%, and 82.3%, respectively (p = 0.60). Tenckhoff catheter removal was needed in 6 cases in the treatment group, 6 cases in the control group, and 13 cases in the historic group (p = 0.90). CONCLUSIONS: We concluded that monotherapy of imipenem/cilastatin has similar efficacy compared to the two standard regimens of cefazolin plus ceftazidime or netilmycin in the treatment of PD peritonitis. 相似文献