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31.
Off-pump coronary artery grafting in patients with left main coronary artery disease 总被引:1,自引:0,他引:1
Virani SS Lombardi P Tehrani H Masroor S Yassin S Salerno T Bolooki H Katariya K 《Journal of cardiac surgery》2005,20(6):537-541
BACKGROUND: Left main coronary artery disease (LMCD) is considered a relative contraindication to off-pump coronary artery bypass (OPCAB) grafting. This study evaluates the safety and feasibility of OPCAB in these patients compared to an on-pump group (cardiopulmonary bypass, CPB) with LMCD. METHODS: Between January 2000 and July 2002, 95 patients with left main coronary artery stenosis >50% underwent coronary revascularization. Seventy-three unselected patients underwent OPCAB and 22 underwent revascularization using CPB. The techniques used for OPCAB included the use of deep traction sutures in the posterior pericardium and stabilizers to expose the distal coronary targets. Intraluminal coronary shunts were routinely used during construction of the anastomoses. Variables were analyzed using a Student's paired t-test with statistical significance defined as p < 0.05. RESULTS: The mean age in the OPCAB group was 59.9 years and the CPB group 61.8 years (p = 0.54). There were 56 males (77%) in the OPCAB and 18 (82%) in the CPB groups. Mean preoperative left ventricular ejection fraction (LVEF) was 40.3% in OPCAB and 47.3% in CPB (p = 0.015). Average number of grafts was 3.1 in OPCAB and 4.1 in CPB (p = 0.0038). There were no conversions to CPB in those patients initially chosen to undergo OPCAB. There were no early deaths in OPCAB. There was one death in CPB. Mean hospital length of stay was 6.9 days for OPCAB and 9.1 for CPB (p = 0.0159). CONCLUSIONS: Patients with LMCD can undergo OPCAB grafting safely and effectively despite reduced LVEF. LMCD should no longer be seen as a contraindication to perform OPCAB grafting. 相似文献
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Cerumen and its micro-chemical analysis 总被引:1,自引:0,他引:1
34.
The reaction of benzoyl peroxide with p-benzoquinone in dilute solutions in chlorobenzene was investigated by isolation and identification of some of the reaction products. The reaction is complex; the identified products were phenyl benzoquinone, benzoyloxy benzoquinone, quinhydrone of p-benzoquinone, benzoic acid, and chlorobiphenyls. There was a considerable amount of tarry quinoid products of unspecific physical properties. Neither simple disubstituted quinoid products, nor mono- or di-ethers of hydroquinone were detected. A mechanism based on these findings has been suggested for the reaction. 相似文献
35.
Jawis MN Singh R Singh HJ Yassin MN 《British journal of sports medicine》2005,39(11):825-9; discussion 825-9
Objectives: Anthropometric and physiological profiles of national sepak takraw players were determined. Methods: Thirty nine players, specialising in the three playing positions (tekong/server, feeder, and killer/spiker) were divided into three age categories of under 15 (U15), under 18 (U18), and under 23 (U23) years of age. Height, weight, percent body fat (%bf), maximum oxygen consumption (Vo2max), range of motion (ROM), back and leg strength, and heart rate, for the estimation of oxygen consumption during matches, were recorded. Statistical analysis was performed using one way ANOVA for independent measurements and data are presented as mean±standard deviation. Results: The U23 players were significantly taller and heavier with significantly better ROM of the neck, trunk, and ankle joints and back and leg strength than the U15 players. No significant difference was found in %bf between the three age categories. Mean maximum heart rate during exercise was significantly higher in the U15 group when compared to the U18 and U23 groups (p<0.05). Mean Vo2max was similar between the three groups. Estimated oxygen consumption during matches was 69.1%, 68.5%, and 56.4% of Vo2max in the killer, tekong, and the feeder groups, respectively. Conclusions: The mean height, body weight, and cardiopulmonary capacities of the players were within the Malaysian population norms, but were somewhat lower than those of players of other court games from other countries. %bf was also lower in these players. This study provides the much needed anthropometric and physiological data of sepak takraw players for further development of this sport. 相似文献
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BACKGROUND: Medical education is reported to be demanding and stressful and previous work with doctors suggests that there is a resistance within the profession to help-seeking and an ad hoc approach to dealing with stress and distress. AIM: To explore the attitudes of medical students at the University of Manchester, UK to the causes of stress and to examine their views on help-seeking. STUDY DESIGN: A qualitative study using semistructured interviews, with analysis of the data using the technique of constant comparison. METHODS: Medical students at the University of Manchester were invited to participate in the study. Sampling made the research representative of medical students in terms of gender, ethnicity and UK/overseas students. Semistructured interviews, with open questions, were conducted and audio-taped with consent. The tapes were transcribed verbatim. The schedule was revised in the light of the emerging themes. RESULTS: Medical students recognised that studying medicine contributes to stress, as experienced in their undergraduate careers. Students reported that perceptions of stigma associated with mental illness, including stress, were prevalent in the student body and were perceived to continue throughout the medical profession. Avoidance of appropriate help-seeking behaviour starts early and is linked to perceived norms which dictate that experiencing a mental health problem may be viewed as a form of weakness and has implications for subsequent successful career progression. CONCLUSION: The preparation of medical students for life as doctors involves more than facilitation of the acquisition of knowledge and skills, so that new doctors can conform to the principals of professional conduct. Support and mentoring are required so that stress can be identified early and dealt with appropriately. 相似文献
39.
Harkin DW Barros D'Sa AA Yassin MM Hoper M Halliday MI Parks TG Campbell FC 《Journal of vascular surgery》2001,33(4):840-846
OBJECTIVES: Hind limb ischemia-reperfusion (I/R) injury increases gut permeability, and resultant endotoxemia is associated with an amplified systemic inflammatory response syndrome leading to multiple organ dysfunction syndrome. We studied the potential role of recombinant bactericidal/permeability-increasing protein (rBPI(21) ), a novel antiendotoxin therapy, in modulating endotoxin-enhanced systemic inflammatory response syndrome in hind limb I/R injury. METHODS: In this prospective, randomized, controlled, experimental animal study, 48 male Wistar rats, weighing 300 to 350 g, were randomized to a control group (sham) and five groups undergoing 3 hours bilateral hind limb ischemia with 2 hours reperfusion (I/R) (n = 8 per group). The control and untreated I/R groups received thaumatin, a control-protein preparation, at 2 mg/kg. Treatment groups were administered rBPI(21) intravenously at 1, 2, or 4 mg/kg body weight at the beginning of reperfusion; an additional group was administered rBPI(21) intravenously at 2 mg/kg after 1 hour of reperfusion. Plasma interleukin-6 concentration was estimated by bioassay as a measure of systemic inflammation. Plasma endotoxin concentration was determined by use of an amebocyte lysate chromogenic assay. Crossreactive immunoglobulin G and M antibodies to the highly conserved inner core region of endotoxin were measured by use of an enzyme-linked immunosorbent assay. The lung tissue wet-to-dry weight ratio and myeloperoxidase concentration were used as markers of edema and neutrophil sequestration, respectively. RESULTS: I/R provoked highly significant elevation in plasma interleukin-6 concentrations (1351.20 pg/mL [860.16 - 1886.40 pg/mL]) compared with controls (125.32 pg/mL [87.76-157.52 pg/mL; P <.0001]), but treatment with rBPI(21) 2 mg/kg at onset of reperfusion (715.89 pg/mL [573.36-847.76 pg/mL]) significantly decreased interleukin-6 response compared with the nontreatment group ( P <.016). I/R increased plasma endotoxin concentrations significantly (21.52 pg/mL [6.20-48.23 pg/mL]), compared with control animals (0.90 pg/mL [0.00-2.30 pg/mL; P <.0001]), and treatment with rBPI(21) 4 mg/kg at reperfusion significantly decreased endotoxemia (1.30 pg/mL [1.20-2.20 pg/mL]), compared with the untreated group ( P <.001). The lung tissue myeloperoxidase level was significantly increased in the untreated I/R group (208.18% [128.79%-221.81%]), compared with in controls (62.00% [40.45%-80.92%; P <.0001]), and attenuated in those treated with rBPI(21) 2 mg/kg (129.54% [90.49%-145.78%; P <.05]). Data represent median and interquartile range, comparisons made with the nonparametric Mann-Whitney U test. CONCLUSIONS: These findings show that hind limb ischemia-reperfusion injury is associated with endotoxemia, elevations in plasma interleukin-6, and pulmonary leukosequestration. Treatment with rBPI(21) after ischemia reduces endotoxemia, the interleukin-6 response, and attenuates pulmonary leukosequestration in response to hind limb reperfusion injury. 相似文献
40.
Omar MH Ong FB Adeeb NN Sharif JM Nasri N Yassin MJ 《The Medical journal of Malaysia》1999,54(1):65-71
A survey in 1996 of our female patients suggest that the three commonest causes of infertility were endometriosis, anovulation and idiopathic which comprises of about 70% of all the patients. In the male patients, sperm morphology evaluation by critical criteria showed that abnormal morphology was present in 71% while 87% of all the semen analysis were abnormal. The objective of this study was to assess the status of IUI before proceeding to formulate patient protocols for IVF in a tertiary infertility referral unit. A retrospective study of patients data was done from Jan 1995 to Dec 1996. Ovarian stimulation by clomiphene for anovulatory and idiopathic patients was performed on couples with at least one patent fallopian tube. Ovulation induction was by an intramuscular injection of 5000 i.u of HCG after follicular maturation. IUI was performed approximately 36-40 hours later. A total of 74 couples received 114 treatment cycles producing a total of 9 conceptions. The conception rate of IUI was therefore 7.89% per cycle and 12.16% per couple with the cumulative pregnancy rate of 28.21%. Associated success features of IUI found in this study were the age of the woman and the semen parameters of the husband. 相似文献