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991.
Wagle AM Sangtam T Au Eong KG 《Retina (Philadelphia, Pa.)》2008,28(2):366; author reply 366-366; author reply 367
992.
Surgeons frequently sustain needlestick injuries when operating. The aim of this study was to evaluate the incidence and reporting rate of needlestick injuries at one institution. A questionnaire was distributed anonymously to 69 surgeons of all grades and specialties in a district general hospital in the UK. The questionnaire was returned by 42 surgeons (60.9%). There were 840 needlestick injuries over two years, of which 126 caused bleeding. Senior surgeons who spent more hours operating per week had a higher rate of needlestick injuries compared with junior surgeons (29.1 vs 6.59 injuries per surgeon over two years). Of the total number of injuries, 19 (2.26%) were reported to Occupational Health according to the surgeons questioned, but only six reported incidents were found in the Occupational Health records. Junior surgeons were significantly more likely to report needlestick injuries than senior surgeons (9.82% vs 1.10% of injuries reported, P=0.0000045). The main reasons for failure to report needlestick injuries were due to the lack of time and excessive paperwork. Seventy-three percent of surgeons did not routinely use double gloves when operating, mainly because of decreased hand sensation. The rate of needlestick injury reporting by surgeons at this institution is extremely low. Previous studies have shown a higher reporting rate suggesting that, despite awareness of blood-borne infections, surgeons are still not following recommended protocols. 相似文献
993.
King AD Vlantis AC Tsang RK Gary TM Au AK Chan CY Kok SY Kwok WT Lui HK Ahuja AT 《AJNR. American journal of neuroradiology》2006,27(6):1288-1291
BACKGROUND: Endoscopic guided biopsy (EGB) is performed after an initial endoscopy for the investigation of patients with suspected nasopharyngeal carcinoma (NPC). The aim of the study was to determine whether MR imaging has the potential to replace invasive EGB in patients with a normal endoscopy. PATIENTS AND METHODS: Data from 2 groups of patients was reviewed, group 1 with proved NPC for MR staging (n = 456) and group 2 with suspected NPC (n = 77). The sensitivity was calculated for group 1 and sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for group 2. RESULTS: In group 1, which included 118 of 456 (26%) with stage 1 disease, cancer was detected in all patients, giving a sensitivity of 100%. In group 2, MR imaging was negative for NPC in 70 (91%) patients, and no cancer has been detected on follow-up (follow-up range, 1-90 months; mean, 36 months). MR imaging was positive for NPC in 7 (9%) patients and NPC was confirmed by biopsy in 3 (4%). Two of these 3 patients had undergone negative endoscopy and biopsy before the MR imaging. NPC was not present in the remaining 4 patients, 2 of whom were found to have lymphoid hyperplasia. MR imaging had a sensitivity of 100%, specificity of 95%, NPV of 100%, PPV of 43%, and accuracy of 95%. CONCLUSION: MR imaging has the potential to screen healthy patients who do not require EGB and direct the site of biopsy in small cancers that may be missed by endoscopy. On the basis of these results, a prospective study is planned. 相似文献
994.
OBJECTIVE: Primary solitary extramedullary and multiple solitary plasmacytomas are rare manifestations of plasma cell tumors. This study reviews their imaging spectrum in 12 patients. CONCLUSION: Imaging features of primary solitary extramedullary and multiple solitary plasmacytomas are nonspecific but are compatible with solid tumors that are isointense on T1-weighted images and iso- to hyperintense on T2-weighted images relative to muscle and white matter with variable enhancement. Large tumors may show necrosis and destruction, infiltration, or encasement of adjacent structures. Multiplicity of lesions and regional lymphadenopathy were evident on imaging in only five cases each. Imaging alone cannot differentiate these tumors from more common malignant entities such as carcinoma, meningioma in cases of intracranial extramedullary plasmacytomas, or metastasis from other primaries. The role of imaging should be focused on early detection of additional or recurrent lesions and the presence of regional lymphadenopathy, which will influence clinical management. 相似文献
995.
Aim: to determine the profile of vitamin D and parathyroid hormone (PTH) and the proportion of vitamin D inadequacy in a population of postmenopausal osteoporotic patients from a rheumatologic outpatient clinic. Methods: a cross sectional study was conducted between October and December 2006 in the Rheumatology Clinic, Cipto Mangunkusumo Hospital with osteoporosis confirmed by bone mineral densitometry (T score less than -2.5 at the lumbar spine or hip). Patients were excluded if there was a history of oral glucocorticoid treatment within 30 days, vitamin D supplementation, and have renal and/or liver function impairments. Forty-two postmenopausal osteoporotic patients aged 51-77 years old who had been postmenopausal for 5-28 years were included in this study. Vitamin D inadequacy was defined as the plasma levels of 25(OH)D less than 50 nmol/L whereas hyperparathyroidism was defined as the PTH level more than 69 pg/dL. Results: vitamin D inadequacy was found in 61.9% of patients and 34.6% of them or 23.8% of total patients were also having high PTH level. There was an inverse correlation between 25(OH)D with PTH levels and positive correlation between duration of menopause and PTH level. Vitamin D inadequacy is common (61.9%) in postmenopausal osteoporotic patients who visited Rheumatology outpatient clinic of Cipto Mangunkusumo Hospital Jakarta. Conclusion: the low concentration of 25(OH)D was correlated with PTH level and duration of menopause. This finding should be confirmed in a larger epidemiological study, either hospital-or community-based to assess vitamin D status among postmenopausal women in Indonesia. 相似文献
996.
In an attempt to investigate the molecular mechanism underlying human glucose-6-phosphate dehydrogenase (G6PD) deficiency caused by two mutations, G6PD(Plymouth) (G163D) and G6PD(Mahidol) (G163S), the two variants were constructed by site-directed mutagenesis and expressed in G6PD-deficient E. coli DF 213 cells. A first indication of impaired folding came from problems in expressing these clinical mutants, which were only overcome by lowering the growth temperature or co-expressing with molecular chaperones (GroEL and GroES). Both strategies significantly increased soluble expression of recombinant G6PD(Plymouth) and G6PD(Mahidol), judged by both G6PD activity in extracts and the amount of immunoreactive protein. Using a modified 3-step protocol, the two mutant enzymes were successfully purified for the first time. Steady-state kinetic parameters (K(m) for NADP(+), K(m) for G6P and k(cat)) of the two mutants are very similar to the wild-type values, indicating that the catalytic efficiency of the two mutants remains unchanged. The two mutants are, however, markedly less stable than wild-type G6PD in both thermostability and urea-induced inactivation tests. In a typical experiment at 37 degrees C and pH 7.2 after 24h G6PD WT, G6PD(Mahidol) and G6PD(Plymouth) retained 58.3%, 27.0% and 3.9%, respectively, of their corresponding initial activity. The stability of all three enzymes is enhanced by addition of NADP(+). According to unfolding and refolding experiments, the two mutants are impaired in their folding properties. Thus structural instability appears to be the molecular basis of the clinical phenotype in G6PD(Plymouth) and G6PD(Mahidol) and in particular of the differing clinical severity of the two mutations. The 3-D structure solved for G6PD(Canton) allows an interpretation of these effects in terms of steric hindrance. 相似文献
997.
Xiao-Rong Wang Ignatius T. S. Yu Yuk Lan Chiu Hong Qiu Zhenming Fu William Goggins Joseph S. K. Au Lap-Ah Tse Tze-Wai Wong 《Cancer causes & control : CCC》2009,20(5):757-763
Chinese women in Hong Kong have among the highest incidence and mortality of lung cancer in the world, in spite of a low prevalence
of smoking. We carried out this population-based case–control study to evaluate the associations of previous lung disease
and family cancer history with the occurrence of lung cancer among them. We selected 212 cases that were newly diagnosed with
primary lung cancer, and randomly sampled 292 controls from the community, frequency matched by age group. All the cases and
controls were lifetime nonsmokers. We estimated the main effects of preexisting asthma, pulmonary tuberculosis, pneumonia,
chronic bronchitis, and family lung/all cancer history, using unconditional logistic regression, accounting for various potential
risk factors and confounders. All of the previous lung diseases, except chronic bronchitis, were related to an elevated risk
for lung cancer, and the association with asthma was significant. Those who had more than one previous lung disease tended
to be at higher risk than those with only one of them. Positive family history of any cancer was associated with over 2-fold
risk than negative family history. The joint effect of positive history of previous pulmonary diseases and positive family
cancer history appeared to be additive, indicating the two factors acted independently. The results support an etiological
link of preexisting lung disease and family cancer history to the risk of lung cancer. 相似文献
998.
999.
Shaheeda Mohamed MPH MRCOphth Gabriel M Leung MD Carmen KM Chan FRCSEd Timothy YY Lai MD Vincent YW Lee FRCS David TL Liu MRCS Kenneth KW Li MRCS Patrick SH Li FCOphth Dennis SC Lam MD 《Clinical & experimental ophthalmology》2009,37(6):602-608
Purpose: To identify factors associated with variability in anatomical and functional response of diabetic macular oedema (DMO) after 4 mg of intravitreal triamcinolone acetonide (ivTA), and for recurrence of macular oedema.
Design: Pooled analysis of individual data from two randomized controlled trials.
Methods: This was a multicentre study involving 107 eyes with DMO administered 4 mg ivTA. Predictive factors for response to treatment were evaluated with linear regression analysis. Factors associated with time to recurrence of oedema were studied with Cox proportional hazards modelling. Main outcome measures were maximum improvement in optical coherence tomography (OCT)-measured central foveal thickness (CFT) and best-corrected visual acuity (BCVA), final CFT and BCVA at 12 months and time to oedema recurrence.
Results: Greater reduction of retinal thickening occurred in eyes with worse baseline thickening ( P < 0.001). There was also greater improvement of visual acuity in eyes with poorer preoperative BCVA levels ( P < 0.001). Age, duration of oedema and previous macular laser treatment had no significant effect on maximal BCVA or CFT improvement. Eyes given 4 mg triamcinolone alone were more likely to develop recurrence of oedema at 12 months than those given a combination of 4 mg triamcinolone plus sequential laser (hazard ratio 2.60 [95% confidence interval: 1.45–4.67]).
Conclusion: Baseline OCT-measured retinal thickening and BCVA are important predictors of maximal anatomical and functional response of DMO to ivTA, respectively. Combination treatment strategy using sequential laser therapy may have a role in delaying recurrence of oedema after triamcinolone. 相似文献
Design: Pooled analysis of individual data from two randomized controlled trials.
Methods: This was a multicentre study involving 107 eyes with DMO administered 4 mg ivTA. Predictive factors for response to treatment were evaluated with linear regression analysis. Factors associated with time to recurrence of oedema were studied with Cox proportional hazards modelling. Main outcome measures were maximum improvement in optical coherence tomography (OCT)-measured central foveal thickness (CFT) and best-corrected visual acuity (BCVA), final CFT and BCVA at 12 months and time to oedema recurrence.
Results: Greater reduction of retinal thickening occurred in eyes with worse baseline thickening ( P < 0.001). There was also greater improvement of visual acuity in eyes with poorer preoperative BCVA levels ( P < 0.001). Age, duration of oedema and previous macular laser treatment had no significant effect on maximal BCVA or CFT improvement. Eyes given 4 mg triamcinolone alone were more likely to develop recurrence of oedema at 12 months than those given a combination of 4 mg triamcinolone plus sequential laser (hazard ratio 2.60 [95% confidence interval: 1.45–4.67]).
Conclusion: Baseline OCT-measured retinal thickening and BCVA are important predictors of maximal anatomical and functional response of DMO to ivTA, respectively. Combination treatment strategy using sequential laser therapy may have a role in delaying recurrence of oedema after triamcinolone. 相似文献
1000.
S. Prabakaran M. Dirani A. Chia G. Gazzard Q. Fan S.-W. Leo Y. Ling K.-G. Au Eong T.-Y. Wong S.-M. Saw 《Ophthalmic & physiological optics》2009,29(4):422-426
Aims: It is common for refraction to be measured using different testing methods in children, with much debate still ongoing on the preferred method. Therefore, we compared cycloplegic refraction measurements using three objective methods in a large cohort of children. Methods: We present the findings from a total of 51 children who were recruited and examined as part of the Strabismus, Amblyopia and Refractive error in Singapore preschool children (STARS) study. Each child underwent a comprehensive eye examination, which included cycloplegic refraction using a hand‐held autorefractor (Retinomax), a table mounted autorefractor (Canon FK‐1) and streak retinoscopy. Spherical equivalent (SE) was calculated as (sphere + half of minus cylinder) and astigmatism was determined using the negative cylindrical component. Results: The current study sample consisted of 29 boys and 22 girls aged between 24 and 72 months (mean age 52.3 months). The mean spherical equivalent (SE) using the table‐mounted autorefractor (1.03 ± 1.64 D) was not significantly different from the streak retinoscopy (1.09 ± 1.58 D, p = 0.66). However, the mean SE using the hand‐held Retinomax (0.80 ± 1.43 D) was significantly different (more ‘minus’p = 0.0004) to streak retinoscopy. The astigmatism measured using the hand held (?0.89 ± 0.51 D) and table‐mounted autorefractor (?0.83 ± 0.61 D) were significantly greater than that obtained with streak retinoscopy (?0.58 ± 0.56, p = 0.0003). Conclusions: The table‐mounted autorefractor provided a reading more similar to that of streak retinoscopy than to that of the hand‐held autorefractor. However, there were only small differences in mean SE (<0.32 D) between the hand‐held Retinomax and the other methods, which will have implications in research investigations of refractive error. 相似文献