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91.
OBJECTIVES: Before the advent of severe acute respiratory syndrome (SARS), use of the powered air-purifying respirator (PAPR) in the setting of pulmonary tuberculosis has been controversial. Data regarding health care worker (HCW) perceptions and problems encountered with the use of the PAPRs were lacking. METHODOLOGY: A questionnaire-based survey was conducted of HCWs who had used the PAPR in clinical practice during the SARS outbreak, when use of the PAPR was mandatory and widespread. Evaluations of the question of whether HCWs were receptive to the use of the PAPR and their perceptions of common problems that were encountered were made. Perceptions of comfort, ease of use, visual, hearing, breathing and speech impairment, perceived protection against SARS and usage preferences were recorded. RESULTS: Only a minority of respondents found the PAPR uncomfortable, despite some interference with communication. Despite its much higher cost, the majority (84%) preferred to use the PAPR rather than the N-95 respirator when treating suspected SARS patients. However, opinions were equally divided regarding its use when treating patients with pulmonary tuberculosis; with 51% being in favour. CONCLUSIONS: With the advent of highly contagious diseases that pose a major occupational hazard to HCWs, the use of the PAPR has become more acceptable in clinical practice. 相似文献
92.
Computer-aided detection in the United Kingdom National Breast Screening Programme: prospective study 总被引:1,自引:0,他引:1
PURPOSE: To evaluate prospectively the recall and cancer detection rates with and without computer-aided detection (CAD) in the United Kingdom National Health Service Breast Screening Programme. MATERIALS AND METHODS: The study had appropriate ethics committee approval. Informed consent was not required; however, patients were informed that their mammograms might be used in research efforts, and all patients agreed to participate. Mammograms obtained in 6111 women (mean age, 58.4 years) undergoing routine screening every 3 years were analyzed with a CAD system. Mammograms were independently double read. Twelve readers participated. Readers recorded an initial evaluation, viewed the CAD prompts, and recorded a final evaluation. Recall to assessment was decided after arbitration. Sensitivities were calculated for single reading, single reading with CAD, and double reading, as a proportion of the total number of cancers detected by using double reading with CAD. RESULTS: A total of 62 cancers were detected in 61 women. CAD prompted 51 (84%) of 61 radiographically detected cancers. Of 12 cancers missed on single reading, nine were correctly prompted; however, seven prompts were overruled by the reader. Sensitivity of single reading was 90.2% (95% confidence interval [CI]: 83.0%, 95.0%), single reading with CAD was 91.5% (95% CI: 85.0%, 96.0%), and double reading without CAD was 98.4% (95% CI: 91.0%, 100%). Cancer detection rate was 1%. Recall to assessment rate was 6.1%, with an increase of 5.8% because of CAD. Average time required, per reader, to read a case was 25 seconds without CAD and 45 seconds with CAD. CONCLUSION: CAD increases sensitivity of single reading by 1.3%, whereas double reading increases sensitivity by 8.2%. 相似文献
93.
94.
Kwek JW Thng CH Tan PH Yuen JS Khoo JB Quek ST Ho JT Tan KP Cheng CW 《Asian journal of surgery / Asian Surgical Association》2004,27(3):219-24; discussion 225-6
PURPOSE: To evaluate local experience of phased-array magnetic resonance imaging (MRI) in the staging of locally advanced prostate carcinoma with comparison to clinical staging. METHODS: The study population was 21 patients who underwent preoperative MRI with pelvic phased-array coils followed by radical prostatectomy. The MRI findings were correlated with completely embedded serially sliced and whole-mounted sections of the prostate gland and clinical staging. RESULTS: Overall accuracy of 57.1% was obtained, with specificity of 90.0% and sensitivity of 27.3%. All but one case of locally advanced disease missed by MRI was microscopic. Clinical staging in these cases also achieved accuracy of 57.1%, specificity of 90.0% and sensitivity of 27.3%. CONCLUSIONS: MRI with a phased-array coil has high specificity but low sensitivity for detection of extraprostatic disease. Phased-array MRI does not image microscopic tumour extension. It did not perform better than clinical staging and is not recommended for routine staging. 相似文献
95.
Khoo JP Nicoli T Alp NJ Fullerton J Flint J Channon KM 《Molecular genetics and metabolism》2004,82(3):251-254
The hph-1 ENU-mutant mouse provides a model of tetrahydrobiopterin deficiency for studying hyperphenylalaninaemia, dopa-response dystonia, and vascular dysfunction. We have successively localized the hph-1 mutation to a congenic interval of 1.6-2.8 Mb, containing the GCH gene encoding GTP cyclohydrolase I (GTP-CH I). We used these data to establish a PCR method for genotyping wild type, hph-1 and heterozygote mice, and found that heterozygote animals have partial tetrahydrobiopterin deficiency. These new findings will extend the utility of the hph-1 mouse in studies of GTP-CH I deficiency. 相似文献
96.
Hendrix CW Jackson KA Whitmore E Guidos A Kretzer R Liss CM Shah LP Khoo KC McLane J Trapnell CB 《Clinical pharmacology and therapeutics》2004,75(5):464-475
BACKGROUND: Isotretinoin is a known teratogen, and when it is prescribed to women of childbearing potential, 2 forms of contraception must be used, commonly including hormonal contraception. Although isotretinoin and estradiol are metabolized largely by cytochrome P450 (CYP) 3A4 and glucuronidation, the potential for clinical drug interaction, with subsequent pharmacodynamic impact, has not been evaluated. METHODS: We enrolled 26 healthy women who were to receive isotretinoin for the treatment of severe, recalcitrant nodular acne and who were taking or planning to take oral contraceptives. The pharmacokinetics of ethinyl estradiol and norethindrone (INN, norethisterone) (the components of Ortho Novum 7/7/7; Ortho-McNeil Pharmaceutical, Inc, Raritan, NJ) and pharmacodynamic assessments of oral contraceptive effectiveness (concentrations of serum progesterone, luteinizing hormone, and follicle-stimulating hormone) were determined on days 6 and 20 of 2 separate oral contraceptive cycles, before and during isotretinoin treatment. RESULTS: The addition of isotretinoin to the oral contraceptive regimen resulted in small and inconsistent, although statistically significant (P <.04), decreases in the concentrations of both ethinyl estradiol (9% decrease in area under the plasma concentration-time curve from time 0 to 24 hours after the dose on day 6) and norethindrone (11% decrease in maximum plasma concentration on day 20). Isotretinoin did not cause any statistically significant increases in pharmacodynamic markers, although a majority of women had increases in these measures. Although there was no correlation between isotretinoin (or metabolite) levels and oral contraceptive levels (P >.05), there was a correlation between progesterone level and oral contraceptive levels (P <.05). Variability was large for both pharmacokinetic measures (median coefficients of variation of 44%-69% [for each time point within a study period]) and pharmacodynamic measures (median coefficients of variation of 64%-114%). One woman in each study phase, one before and one during isotretinoin treatment, had a progesterone elevation consistent with possible ovulation. No serious or unexpected adverse events were observed. CONCLUSIONS: The small reduction in ethinyl estradiol and norethindrone levels associated with isotretinoin was not associated with any pharmacodynamic changes in our study. The combination of the teratogenic risk of isotretinoin and the large variability of and correlation between oral contraceptive levels and pharmacodynamic measures, however, strongly reinforces the necessity of additional contraceptive methods during concomitant administration of these drugs. 相似文献
97.
Gill GV Beeching NJ Khoo S Bailey JW Partridge S Blundell JW Luksza AR 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2004,98(6):382-386
A case is described of a 78-year-old British veteran of the Second World War (1939-45) who was stationed in Southeast Asia and who developed a recurrent pneumonia with blood eosinophilia. He was treated with steroids, and eventually died with a severe Pseudomonas pneumonia. Just prior to death, larvae of Strongyloides stercoralis were identified in his sputum, and a specific serum ELISA test was later positive. At autopsy no other organs were involved, but bronchoalveolar carcinoma was found. Longstanding (57 years) chronic strongyloidiasis in a veteran who served in Southeast Asia but who was not a prisoner of war is very unusual. The pattern of dissemination was also not that of a true hyperinfection syndrome, and the case demonstrates the continued need for diagnostic vigilance amongst former soldiers who were based in the Far East. 相似文献
98.
During pregnancy, lower levels of maternal glucose before and during a glucose load have been associated with reduced infant birth weight and an increased risk of small-for-gestational-age births. A lower incremental area under the glucose response curve defines a low glycemic diet. Thus, during pregnancy the maternal diet, as measured by the glycemic index, may influence fetal growth and infant birth weight. A total of 1,082 gravidas who enrolled in the Camden Study between August 1996 and October 2002 were followed prospectively during pregnancy. The dietary glycemic index was computed from three 24-hour recalls in the course of pregnancy. Samples for plasma glucose and for glycosylated hemoglobin were obtained at 24-28 weeks' gestation. The glycemic index was positively and significantly related to maternal glycosylated hemoglobin and plasma glucose. There were as well significant linear trends for dietary fat intake to decrease and for intakes of carbohydrate, sucrose, fiber, and folate to increase as the glycemic index declined. Gravidas with a low dietary glycemic index had reduced infant birth weight and approximately a twofold increased risk of a small-for-gestational-age birth. Consistent with data on maternal plasma glucose, data in this study show that the type of carbohydrate in the diet of urban, low-income women influences fetal growth and infant birth weight. 相似文献
99.
Atypical squamous cells of undetermined significance on cervical smears: follow-up study of an Asian screening population 总被引:2,自引:0,他引:2
BACKGROUND: The current study reports on the significance of cervical smears identified as atypical squamous cells of undetermined significance (ASCUS) in the largest Asian screening population to date. METHODS: From January 1998 to December 1999, 190,000 cervical smears were evaluated by the cervical cytology laboratory at the University of Hong Kong (Hong Kong, China). From these smears, 5579 ASCUS were identified. Follow-up cytology and histology findings were analyzed. RESULTS: Follow-up cytology or biopsy results were retrieved for 3601 women (64.5%). Of these, 544 (9.8%) and 96 women (1.7%) were found to have low-grade (LSIL) and high-grade (HSIL) squamous intraepithelial lesions, respectively. Biopsy results were obtained for 198 (36.4%) of the 544 women with LSIL. One hundred seventy-nine (32.9%) and 19 women (3.5%) were confirmed to have cervical intraepithelial neoplasia (CIN)-1 and CIN-2-CIN-3, respectively. Biopsy results were retrieved for 53 (55.2%) women with HSIL. Forty patients (41.7%) were confirmed to have CIN-2-CIN-3, whereas CIN-1 was found in the remaining patients. One woman with squamous cell carcinoma was diagnosed by colposcopic biopsy after immediate referral following a diagnosis of ASCUS. There was a significantly larger proportion of LSIL or HSIL (P < 0.0001) or higher-grade findings in women with ASCUS compared with the general screening population. Infective organisms were identified in 412 women (7.4%) with ASCUS. These women had a decreased risk of subsequent development of LSIL (P < 0.0001) or HSIL (P = 0.027). CONCLUSIONS: ASCUS smears indicated an increased risk of HSIL or carcinoma. The authors suggested careful patient follow-up in such cases. 相似文献
100.
Khoo VS Saunders MP Gowda R Price P Cummings BJ 《Clinical oncology (Royal College of Radiologists (Great Britain))》2004,16(1):1-5
Two case reports of anal cancer developing during chronic therapeutic immunosuppression for systemic lupus erythematosus (SLE) and their cancer management are presented. The complex issues of delivery of curative chemoradiation treatment for anal cancer in the context of co-existing autoimmune connective tissue disease (AICD) are discussed. These two cases show that combined chemotherapy and radiation regimens are possible in patients with SLE. However, frequent, careful assessment with judicious and prompt management of haematological and other complications during treatment is important. 相似文献