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101.
Mak JC Leung HC Ho SP Law BK Lam WK Tsang KW Ip MS Chan-Yeung M 《The Journal of allergy and clinical immunology》2004,114(2):260-264
BACKGROUND: Patients with asthma generate an increased amount of reactive oxygen species from peripheral blood cells. Reactive oxygen species produce many of the pathophysiologic changes associated with asthma and may contribute to its pathogenesis. OBJECTIVE: We investigated changes in antioxidant enzyme activities and oxidized glutathione (glutathione disulfide; GSSG) levels in erythrocytes from a group of healthy control Chinese subjects (n=135) and patients with asthma (n=106). METHODS: Baseline pulmonary function was measured for all subjects. Antioxidant status was evaluated by measuring erythrocyte superoxide dismutase, catalase, and glutathione peroxidase activities. Oxidative stress was also measured in terms of GSSG in erythrocytes with a kinetic microassay. RESULTS: Patients with asthma had significantly increased erythrocyte superoxide dismutase and catalase activities compared with controls (61.10 +/- 1.30 U/g hemoglobin [Hb] vs 55.51 +/- 1.82 U/g Hb [P=.018] and 0.0637 +/- 0.0021 U/g Hb vs 0.0257 +/- 0.0120 U/g Hb [P <.001] for the asthma and control groups, respectively). Conversely, erythrocyte glutathione peroxidase activity decreased (44.21 +/- 1.33 mU/g Hb vs 50.07 +/- 1.39 mU/g Hb for the asthma and control groups, respectively; P=.003). Patients with asthma also had significantly higher GSSG levels in erythrocyte hemolysates compared with controls (167.40 +/- 2.93 micromol/L vs 44.98 +/- 0.44 micromol/L for the asthma and control groups, respectively; P <.001), indicating increased oxidative stress. CONCLUSIONS: Asthma is accompanied by an alteration in systemic antioxidant status due to possible oxidative stress in this disease. 相似文献
102.
Tripathi SC Kaur J Matta A Gao X Sun B Chauhan SS Thakar A Shukla NK Duggal R Choudhary AR DattaGupta S Sharma MC Ralhan R Siu KW 《Modern pathology》2012,25(1):14-25
Deleted in liver cancer (DLC1), a Rho GTPase-activating protein, was observed to be differentially expressed in oral squamous cell carcinoma in comparison with normal tissues using tissue proteomics. In the current study, we investigated the clinical significance of loss of DLC1 expression in different stages of development of oral squamous cell carcinoma to determine its potential as a biomarker for oral dysplasia and prognosis of oral squamous cell carcinoma. Immunohistochemical analysis of DLC1 expression was carried out in oral squamous cell carcinoma patients (n=214), dysplasia (n=51), hyperplastic squamous mucosa (n=45), and histologically normal oral tissues (n=80), and correlated with clinicopathological parameters and disease prognosis over 91 months for oral squamous cell carcinomas. Loss of DLC1 expression was observed in oral squamous cell carcinoma (64%), oral dysplasia (31%), hyperplastic squamous mucosa (22%), and normal mucosa (16%). Significant loss of DLC1 expression was observed in oral squamous cell carcinomas as compared with dysplasia (P<0.001, odds ratio=3.8, 95% CI=2.0-7.3), suggesting it may be an important event involved in cancer progression. Among oral squamous cell carcinomas, the loss of DLC1 expression was significantly associated with poor prognosis (P=0.021, hazards ratio (HR)=1.8, 95% CI=1.1-2.9). Multivariate analysis revealed loss of DLC1 (P=0.023, HR=2.1, 95% CI=1.2-3.9) and histopathological grade (P=0.015, HR=1.7, 95% CI=1.1-2.7) to be independent predictors for disease-free survival in oral squamous cell carcinoma patients in comparison with known prognostic factors, viz. tumor stage, nodal status, and overall stage. Loss of DLC1 expression emerged as an important biomarker for predicting patients diagnosed with oral dysplasia at high risk of transformation upon future validation in longitudinal studies. Loss of DLC1 expression is a poor prognostic marker for oral squamous cell carcinoma patients. 相似文献
103.
Chinese medicine has been used to treat a variety of cancer-related conditions. This study aims to examine the prevalence and patterns of Chinese medicine usage by cancer patients. We reviewed articles written in English and found only the Chinese medicine usage from the studies on complementary and alternative medicine (CAM). Seventy four (74) out of 81 articles reported rates of CAM usage ranging from 2.6 to 100%. Acupuncture was reported in 71 out of 81 studies. Other less commonly reported modalities included Qigong (n = 17), Chinese herbal medicine (n = 11), Taichi (n = 10), acupressure (n = 6), moxibustion (n = 2), Chinese dietary therapy (n = 1), Chinese massage (n = 1), cupping (n = 1) and other Chinese medicine modalities (n = 19). This review also found important limitations of the English language articles on CAM usage in cancer patients. Our results show that Chinese medicine, in particular Chinese herbal medicine, is commonly used by cancer patients. Further research is warranted to include studies not written in English. 相似文献
104.
Gatzoulis MA Freeman MA Siu SC Webb GD Harris L 《The New England journal of medicine》1999,340(11):839-846
BACKGROUND: Atrial flutter and atrial fibrillation are causes of morbidity in adults with an atrial septal defect. In this study, we attempted to identify risk factors for atrial flutter and fibrillation both before and after the surgical closure of an atrial septal defect. METHODS: We searched for preoperative and postoperative atrial flutter or fibrillation in 213 adult patients (82 men and 131 women) who underwent surgical closure of atrial septal defects because of symptoms, a substantial left-to-right shunt (ratio of pulmonary to systemic blood flow, >1.5:1), or both at Toronto Hospital between 1986 and 1997. RESULTS: Forty patients (19 percent) had sustained atrial flutter or fibrillation before surgery. As compared with the patients who did not have atrial flutter or fibrillation before surgery, those who did were older (59+/-11 vs. 37+/-13 years, P<0.001) and had higher mean pulmonary arterial pressures (25.0+/-9.7 vs. 19.7+/-8.2 mm Hg, P=0.001). There were no perioperative deaths. After a mean follow-up period of 3.8+/-2.5 years, 24 of the 40 patients (60 percent) continued to have atrial flutter or fibrillation. The mean age of these patients was greater than that of the 16 who converted to sinus rhythm (P=0.02). New-onset atrial flutter or atrial fibrillation was more likely to have developed at follow-up in patients who were older than 40 years at the time of surgery than in those who were 40 or younger (5 of 67 vs. 0 of 106, P=0.008). Late events (those occurring more than one month after surgery) included stroke in six patients (all but one with atrial flutter or fibrillation, one of whom died) and death from noncardiac causes in two patients. Multivariate analysis showed that older age (>40 years) at the time of surgery (P=0.001), the presence of preoperative atrial flutter or fibrillation (P<0.001), and the presence of postoperative atrial flutter or fibrillation or junctional rhythm (P=0.02) were predictive of late postoperative atrial flutter or fibrillation. CONCLUSIONS: The risk of atrial flutter or atrial fibrillation in adults with atrial septal defects is related to the age at the time of surgical repair and the pulmonary arterial pressure. To reduce the morbidity associated with atrial flutter and fibrillation, the timely closure of atrial septal defects is warranted. 相似文献
105.
JS Tsang Chi Chung Foo Jeremy Yip Hok Kwok Choi Wai Lun Law Oswens Siu Hung Lo 《The surgeon》2021,19(3):150-155
IntroductionThe difference in outcome between right (RCD) and left colonic diverticulitis (LCD) is not well established. The aim of this study was to analyse the presentation and surgical outcome of RCD versus left-sided disease following emergency surgery.MethodWe conducted a retrospective review of patients presenting with acute diverticulitis over a 10-year period from 2004 to 2014 to a tertiary unit. Patient demographics, Hinchey classification, need for emergency surgery, perioperative outcome and recurrence were evaluated.ResultsIn total 360 patients presented with acute diverticulitis, 218 (61%) were right-sided and 142 (39%) were left-sided. The mean age (57 yrs vs 68 yrs) and median length of stay (4 days vs 5 days) were significantly less in RCD (p < 0.001). The need for emergency surgery was similar between RCD and LCD (30.7% vs 23.2%, p = 0.12). Sixty-seven (31%) patients with RCD required emergency surgery, 42 (62.7%) of these were based on a presumptive diagnosis of appendicitis and underwent laparoscopic appendicectomy only. Operative morbidity (10.4% vs 51.5%, p < 0.001) and mortality were significantly higher in LCD (1.5% v 15.2%, p = 0.007). Subgroup analysis of non-appendicectomy, RCD patients, showed LCD were more likely to require surgery (11.5% vs 23.2%, p = 0.003). There was no difference in recurrence (p = 0.6).ConclusionRight colonic diverticulitis patients are younger and disease course is more benign compared to LCD. Presentation can be confused with appendicitis without proper imaging. In the rare cases where emergency surgery is required, RCD is associated with a lower operative morbidity and mortality compared to left-sided disease. 相似文献
106.
Ka Wing Ma Albert Chi Yan Chan Kenneth Siu Ho Chok Wong Hoi She Tan To Cheung Wing Chiu Dai James Yan Yue Fung Chung Mau Lo 《肝胆外科与营养》2021,10(3):308
BackgroundHepatocellular carcinoma (HCC) with portal vein tumour thrombus (PVTT) signifies advanced disease, whether LT confers any survival superiority over resection remains uncertain.MethodsA propensity score matched (PSM) analysis of liver transplantation (LT) and liver resection (LR) for HCC with PVTT was performed.ResultsA consecutive series of 88 patients who received either LT (10 DDLTs and 3 LDLTs) or LR (n=75) respectively were recruited. Before PSM, the LT group has a higher MELD score (17.3 vs. 7.8, P<0.001), lower serum AFP levels (96 vs. 2,164 ng/mL, P=0.017) and smaller tumour size (4 vs. 10 cm, P<0.001). The 5-year overall survival for LT and LR were 55.4% and 15.9% respectively (P=0.007). After matching for serum AFP levels and tumour size, 1-, 3- and 5-year overall survival for LT were 81 ng/mL, 3.9 cm, 80%, 70% and 70% and the corresponding rates for LR were 1,417 ng/mL, 5.3 cm, 51.8%, 19,6% and 9.8% (P value =0.12, 0.27 and 0.009 respectively).ConclusionsLT is associated with significantly better oncological outcomes in HCC patients with PVTT involving the lobar or segmental level. A modest expansion of selection criteria to include small HCC with segmental PVTT should be considered. 相似文献
107.
PURPOSE: The objective of this study was to investigate modulation in prelanding muscle responses and its associated impact force on landing from unexpected and self-initiated drops in male basketball players with a history of bilateral multiple ankle sprains (BMAS). METHODS: Prelanding EMG responses were recorded in four lower-limb muscles, together with the impact force on landing, while 20 healthy and 19 basketball players with BMAS performed unexpected, self-initiated drops from a height of 30 cm. RESULTS: Group differences were detected after self-initiated but not unexpected drops. Two main changes in prelanding EMG responses were observed in the injured basketball players during the self-initiated drops. First, tibialis anterior (TA) was activated significantly earlier in the injured group, whereas left tensor fascia latae appeared closer to the moment of landing (P < 0.025) than in the healthy players. Second, cocontraction indexes between left TA and peroneus longus, and left TA and medial gastrocnemius, were significantly greater in the injured than in the healthy players (P < 0.025). On landing, higher magnitude-of-impact forces were observed in the injured players on the right leg (by 23%, P = 0.012). CONCLUSION: In basketball players with BMAS, modulation of prelanding muscle response latencies occurred in injured (ankle) and uninjured (hip) joints during self-initiated but not unexpected drops. Greater cocontraction index between the left ankle muscle pairs in preparation for landing from self-initiated drops, and a significantly higher magnitude of impact force in the right leg on landing, were observed in the injured players. 相似文献
108.
Siu WT Law BK Tang CN Chau CH Li MK 《Journal of laparoendoscopic & advanced surgical techniques. Part A》2003,13(3):199-201
Torsion of the greater omentum is an uncommon surgical emergency. Most of the reported cases have been primary omental torsion with infarction, in which the underlying cause is largely unknown. Right-sided abdominal symptoms are the predominant complaint. Left-sided omental torsion is rather infrequent, and the preoperative diagnosis is extremely difficult. We report a case of omental torsion secondary to an occult left indirect inguinal hernia that was successfully diagnosed and managed laparoscopically. 相似文献
109.
Siu Hong Cheung Wai Yin Wilson Kwan Kwan Pok Tsui Tam Lin Chow 《American journal of otolaryngology》2018,39(3):286-289
Purpose
Benign parotid tumors are adequately treated with partial parotidectomy, which is often performed under general anesthesia (GA). We have reported our preliminary results on the feasibility to perform parotidectomy under local anesthesia (LA). We hereby present our accumulated experience of partial parotidectomy under LA to further consolidate its feasibility, efficacy and safety in a larger series.Materials and methods
Case series review was carried out using our own center patients' database. 50 patients with parotid tumors were treated with partial parotidectomy under LA, using a retrograde nerve dissection approach from January 2006 to October 2016. The inclusion criteria encompassed mobile parotid nodules primarily operated after non-suspicious fine-needle aspiration cytology. Their demographics, complications and outcomes were evaluated.Results
No procedure required conversion to GA. There were 48 benign tumors and 2 lymphomas based on the histopathologic examination. The commonest pathologies were pleomorphic adenoma (40%), Warthin's tumor (38%) and cyst (8%). The mean tumor size was 2.68?±?1.5?cm and the mean operative time was 91.5?±?34.7?min. Forty-two operations were done as day cases. Ten (20%) patients suffered from transient ear lobe numbness and two (4%) patients had sialocele. Transient facial palsy occurred in 2(4%) patients while another patient (2%) had persistent House-Brackmann grade II facial palsy. No tumor recurrence was noted during follow-up period.Conclusions
Partial parotidectomy adopting a retrograde nerve dissection under LA is feasible and minimally invasive in treating benign parotid tumors. It can avoid the adverse effects of general anesthesia and promote day surgery or minimize hospital stay. 相似文献110.