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51.
Eric Y. T. Chan Daniel K. Ng Chung-hong Chan Ka-li Kwok Pok-yu Chow Josephine M. Cheung Suk-yu Leung 《Sleep & breathing》2009,13(1):59-63
Background and objective The purpose of this study is to assess whether Chinese children with high apnea–hypopnea index (AHI) are sleepier by a modified Epworth Sleepiness Scale (ESS).
Materials and methods Records were retrospectively reviewed. We included children who were between 3 and 12 years old, admitted for overnight polysomnogram
because of suspected obstructive sleep apnea syndrome (OSAS). A modified ESS was used to assess excessive daytime sleepiness
(EDS) of the children.
Results One hundred ninety-two Chinese children were included. Children with high AHI, defined as AHI > 5.0, were sleepier than children with AHI less than or equal
to 5. After adjustment by age, gender, and obesity, children with high AHI remained significantly sleepier. Modified ESS was
significantly correlated with AHI (rho = 0.124, 95% CI = 0.004–0.281). Modified ESS score of >8 was the best cutoff point
with the sensitivity and specificity of 0.29 and 0.91, respectively. The odds ratio of children with modified ESS > 10 having
high AHI was 4.231 (95%CI = 1.248 to 14.338) and children with modified ESS > 8 had the highest odds ratio, 4.295(95%CI = 1.66
to 11.1), of having high AHI.
Conclusion
Chinese children with high AHI appear to be sleepier than children with low AHI. Children with suspected OSAS and high modified ESS,
i.e., ESS > 8, had significantly higher odds ratio of having high AHI. Increased sleepiness is a specific but not a sensitive
symptom in snoring children with high AHI. Screening for EDS in snoring children may help us identify those with high AHI
and prioritize the management of those children.
All authors worked and the study was carried out in Kwong Wah Hospital in Hong Kong. There was no conflict of interest and
no specific source of funding for the study. 相似文献
52.
A S Brickman A L Trujillo M S Gutin M L Tuck 《The Journal of clinical endocrinology and metabolism》1987,64(2):297-303
ACTH-, angiotensin II (AII)-, and K+-mediated aldosterone responses in vitro are dependent on extracellular and intracellular Ca concentrations. This study examined in vivo the relationship of changes in ambient serum calcium (serum Ca) to ACTH- and AII-mediated aldosterone release in hypoparathyroid subjects. Plasma aldosterone (PA) responses to graded dose infusions of ACTH and AII were examined in hypoparathyroid (HypoPTH) patients before (n = 8) and after correction of hypocalcemia (n = 6) and compared to responses in 20 normotensive normocalcemic subjects. ACTH and AII were infused for 90 min at rates increasing from 12.5 to 50 mIU/30 min and 0.5 to 2.0 ng/kg X min, respectively. Pretreatment mean serum Ca was 6.8 +/- 0.2 (+/- SEM) mg/dl, and it rose to 9.3 +/- 0.2 mg/dl after 3-8 weeks of vitamin D administration. In the untreated HypoPTH patients, basal mean PA (5.4 +/- 1.3 ng/dl) was lower (P less than 0.01) than in the normal subjects (10.6 +/- 0.6 ng/dl) or treated HypoPTH patients (9.5 +/- 1.8 ng/dl). There was a marked reduction in PA responses to ACTH at all doses in the untreated HypoPTH patients compared to the normal subjects. With normalization of serum Ca in four patients, the mean peak PA response to ACTH (25.1 +/- 6.0 ng/dl) was not significantly different from normal (28.9 +/- 1.7 ng/dl). During graded dose AII infusion in five untreated HypoPTH patients, mean PA levels increased from 6.9 +/- 1.2 to 11.6 +/- 2.2 ng/dl; when the serum Ca was normal, the corresponding values were 8.7 +/- 1.8 and 20.2 +/- 3.61 ng/dl. There was a positive correlation (r = 0.475; P less than 0.05) between basal PA and serum Ca levels. In addition, maximum changes in mean arterial pressure in response to AII infusions were significantly greater after correction of hypocalcemia. These observations indicate that in HypoPTH patients, extracellular Ca concentrations can influence humoral aldosterone response to ACTH and AII and pressor responses to AII. 相似文献
53.
Henry Ho‐Lung Chan 《Clinical & experimental optometry》2005,88(6):410-414
The first‐order kernel analysis in multifocal electroretinogram (mfERG) using low contrast stimulation is suggested as a way to detect the inner retinal responses in animal studies. In this case report, this protocol is applied to human patients with glaucoma to demonstrate the possibility of using mfERG as a tool to detect glaucomatous damage. Two patients with glaucoma were recruited and had mfERG measurements with the 103‐scaled hexagonal stimulus pattern at low (50 per cent) contrast. Their responses were analysed and compared with those from normal subjects with the mfERG measured under the same condition. In the normal subjects, there were obvious oscillatory components on the ascending and descending limbs of the first‐order kernel response to 50 per cent contrast. In the glaucomatous patients, the oscillatory component on the descending limb was obviously diminished. In addition, this component was significantly diminished in the quadrant with a glaucomatous visual field defect. This suggests that the low‐contrast stimulation condition in mERG measurement may provide a good way to detect glaucomatous damage and this may help in clinical diagnosis of glaucoma. 相似文献
54.
Anterior mediastinal immature teratoma with precocious puberty in a child with Klinefelter syndrome.
Pen-Hua Su Shi-Ping Luh Da-Mien Yieh Jia-Yuh Chen Suh-Jen Chen Huei-Mei Hung Pei-Fen Liao 《台湾医志》2005,104(8):601-604
ABSTRACT: Klinefelter syndrome occurs in approximately 1 in 1000 males. A 4-year-old boy presented with precocious puberty and an anterior mediastinal mass. Serum alpha-fetoprotein and human chorionic gonadotropin levels were mildly increased. Computed tomography revealed a germ cell tumor (GCT) of the mediastinum. Complete resection of the tumor was performed. Histologic analysis revealed an immature teratoma. Males with Klinefelter syndrome develop GCTs at a rate 50 times higher than unaffected males. This case report calls attention to the need to rule out Klinefelter syndrome in boys who present with precocious puberty and a mediastinal GCT. 相似文献
55.
Factors influencing family physicians to enter rural practice: Does rural or urban background make a difference? 下载免费PDF全文
56.
Roger S Chan Michael H Duong Aaron V Kaplan 《Catheterization and cardiovascular interventions》2007,70(3):374-378
Percutaneous intervention in saphenous vein grafts (SVG) carries a higher risk of distal embolization than intervention in a native vessel, and use of a distal protection device has been shown to improve the outcomes in SVG interventions. We describe an intervention done in an unexpected 'Y' SVG which required dual distal protection with Filterwires placed in both limbs of the diseased graft and which was performed via a 6 Fr guide catheter. 相似文献
57.
Digital mammography. ROC studies of the effects of pixel size and unsharp-mask filtering on the detection of subtle microcalcifications 总被引:3,自引:0,他引:3
H P Chan C J Vyborny H MacMahon C E Metz K Doi E A Sickles 《Investigative radiology》1987,22(7):581-589
We investigated the spatial resolution requirement and the effect of unsharp-mask filtering on the detectability of subtle microcalcifications in digital mammography. Digital images were obtained by digitizing conventional screen-film mammograms with a 0.1 X 0.1 mm2 pixel size, processed with unsharp masking, and then reconstituted on film with a Fuji image processing/simulation system (Fuji Photo Film Co., Tokyo, Japan). Twenty normal cases and 12 cases with subtle microcalcifications were included. Observer performance experiments were conducted to assess the detectability of subtle microcalcifications in the conventional, the unprocessed digital, and the unsharp-masked mammograms. The observer response data were evaluated using receiver operating characteristic (ROC) and LROC (ROC with localization) analyses. Our results indicate that digital mammograms obtained with 0.1 X 0.1 mm2 pixels provide lower detectability than the conventional screen-film mammograms. The detectability of microcalcifications in the digital mammograms is improved by unsharp-mask filtering; the processed mammograms still provide lower accuracy than the conventional mammograms, however, chiefly because of increased false-positive detection rates for the processed images at each subjective confidence level. Viewing unprocessed digital and unsharp-masked images in pairs resulted in approximately the same detectability as that obtained with the unsharp-masked images alone. However, this result may be influenced by the fact that the same limited viewing time was necessarily divided between the two images. 相似文献
58.
A W Chan 《Drug and alcohol dependence》1987,19(2):99-119
Although the relationship between alcohol and traffic safety has been the subject of numerous studies, much remains unknown about the mechanisms by which alcohol contributes to traffic accidents. A number of other factors, which are reviewed in this paper, also can contribute to car accidents. They may also interact with alcohol, perhaps in a complex manner. Therefore, multiple factors rather than one single factor may contribute to automobile accidents for those who drink and drive. 相似文献
59.
Sung-Ching Pan Szu-Min Hsieh Chien-Ching Hung Pei-Fong Huang Mao-Yuan Chen Shan-Chwen Chang 《Journal of microbiology, immunology, and infection》2005,38(1):31-34
This study evaluated the feasibility of reducing the indinavir (IDV) dosage in Taiwanese patients receiving the standard IDV/ritonavir (RTV) dosage of 800/100 mg twice a day who had undetectable plasma human immunodeficiency virus type 1 (HIV-1) RNA but had developed IDV-related toxicities. After dosage reduction to IDV/RTV 600/100 mg twice a day, the dose-related toxicity decreased and plasma HIV RNA remained undetectable at 24 weeks post-switch in all patients. The maximal plasma concentration (Cmax) and area under the plasma concentration-time curve of IDV decreased significantly (median, 6.3 vs 4.3 microg/mL and 1892 vs 1292 microg.min/mL, p=0.01 and 0.001, respectively) but the minimal plasma concentration remained at a similar level (median, 1.0 vs 0.8 microg/mL, p=0.12). This study found that the reduction in the dosage of IDV in HIV-1 infected patients receiving the standard IDV/RTV regimen guided by therapeutic drug monitoring decreased the Cmax, dose-related toxicity and medical cost without compromising viral control. 相似文献
60.
Oswens Siu Hung Lo Wai Lun Law Hok Kwok Choi Yee Man Lee Judy Wai Chu Ho Chi Leung Seto 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(2):173-178
OBJECTIVES: The study aimed to review the etiologies of patients who underwent surgery for small bowel obstruction (SBO) and to evaluate the risk factors affecting the early postoperative outcomes. MATERIALS AND METHODS: A case series of 430 patients (252 men) with a mean age of 64.5 years, who underwent 437 operations for SBO, were retrospectively reviewed. RESULTS: Peritoneal adhesions and hernia were the most common causes of SBO, contributing 42.3 and 26.8% of all cases, respectively. Strangulation occurred in 27.7% and caused nonviable bowel in 13.0% of obstructing episodes. Old age (age >/= 70 years), female patient, nonadhesive obstruction, and hernia were the independent significant factors associated with bowel strangulation. The 30-day mortality was 6.5%, and the median postoperative hospital stay was 8 days. Old age, the presence of premorbid pulmonary disease, and malignant obstruction were the independent factors associated with operative mortality. The overall complication rate was 35.5%, and old age was the only significant factor associated with postoperative complications. CONCLUSIONS: Surgery for SBO is still associated with significant mortality and morbidity. As old age is significantly associated with an increased incidence of strangulation, operative mortality, and complications, this group of patients should be managed with extra cautions to avoid unfavorable outcome of surgery. 相似文献