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The frequency of reversible and irreversible visual impairment was determined in children with severe and profound sensorineural deafness, as subnormal vision can adversely affect their educational and social development. Eighty three of 87 such children attending an audiology service were examined to assess the incidence and severity of visual impairment. Each child underwent a detailed ophthalmic assessment. The criteria for visual impairment were visual acuity < 6/9 Snellen or equivalent and/or abnormal binocular vision. Forty five had a normal ophthalmic examination (54.2%). Twenty nine had visual impairment (34.9%) and nine had ophthalmological abnormalities that did not interfere with vision (10.9%). A higher proportion of children with risk factors for visual pathology demonstrated visual impairment than those in whom there were no risk factors. None the less, 44% of visual impairment was among patients without risk factors. The results underline the need to examine all children with severe and profound sensorineural deafness soon after diagnosis and indicate that children with multiple handicaps have a greater likelihood of visual impairment (11 of 14 cases).  相似文献   
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To assess the effect of different hospital types or surgical volume on the survival of ovarian cancer patients, a nationwide and population-based analysis was carried out in Finland. The study included all 3,851 ovarian cancer patients operated from 1983-94. The patients were classified according to the hospital of the first surgery. The hospitals were categorized by type (university, central or other hospital) and, separately, into quartiles by the number of operated patients (surgical volume). The patients operated at university hospitals had better survival than those operated in central hospitals, the 5-year relative survival rates (RSR) being 45% (95% CI = 42-48%) and 37% (34-40%), respectively. RSR in the 'other hospital' category was 45% (42-48%). The RSR for the patients operated in the highest volume hospitals was 47% (43-50%), and by decreasing volume (quartile) the RSR was 40% (36-43%), 40% (36-43%) and 42% (38-45%), respectively. After controlling for potential confounding by stage and age using regression models, the results remained practically the same. The results indicate that further centralizing of operative treatment of ovarian cancer may still improve survival rates on a population level in Finland.  相似文献   
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Lymphotoxin-α (LTA) is a cytokine involved in inflammatory reactions. NFKBIL1 is a regulator of the NF-κB complex. The study investigated the associations of LTA 804 C>A and NFKBIL1-63 T>A polymorphisms with the use of statin and acetylsalicylic acid (ASA) treatment in relation to myocardial infarction (MI). The study population comprised of 600 Finnish individuals who underwent coronary angiography volunteering for the Angiography and Genes Study. Genotypes were detected by the TaqMan 5′ nuclease assay. We found a interaction between the LTA genotype (p=0.002) and the NFKBIL1 genotype (p=0.012) and statin treatment in relation to MI. Subjects with the LTA AA or the NFKBIL1 AA genotype were at a 2.77 (95% CI:1.22-6.24) and 2.85 (95% CI:1.22-6.66) times higher risk, respectively, of suffering an MI when compared to other genotypes among statin non-users. ASA treatment also modulated associations between LTA and NFKBIL1 genotypes and MI (p=0.015 and p=0.028 respectively). The NFKBIL1-A-LTA-A haplotype showed a 61% increase in the risk of MI compared to the NFKBIL1-T-LTA-C haplotype among statin non-users. Anti-inflammatory medication modifies the genotype-related risk of MI, suggesting that subjects with LTA and NFKBIL1 AA haplotype might especially benefit from the treatment.  相似文献   
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目的使用非线性成长率理论分析人眼视力发展规律。方法使用高斯光学及成像方程推导出两个参数:屈光状态改变率(M)及眼轴成长率(N),用以预测MOS(初始近视)、年龄(A^*)及其后视力的发展情况。结果当有效焦距F=(21-22)、密码M=(2.67—2.9)(D/mm)时,此计算值符合实验平均值(2.7)。当年龄A^*=(3,6)岁的屈光度变化已知时,我们计算其MOS预测年龄为A^*=(7.3,21.8)岁(在不同条件下)。此值反比于M值在A=6及A=3的比值或N=N—N^*,即非正视态及正视态的眼轴成长率之差。本理论也可用来预测在年龄A=25时的近视度,分别为D=-14及-0.49的上述两例情况,同时也能分析Lain等人的测量值(由出生到青年期的视力发展情况)。结论本理论可预测MOS、其后发展情况及其符合实验值(M)。使用成长率差值(dN)比使用L/rl比值能更准确地预测MOS。  相似文献   
27.
Patients with carcinoma of the biliary tract have a poor prognosis because the disease is often unresectable at diagnosis. Intraluminal brachytherapy has been reported as an effective treatment for localized cholangiocarcinoma of the biliary tract. The purpose of our study was to analyse the survival of patients treated with brachytherapy and make some recommendations regarding its use. Fifteen patients underwent brachytherapy via a trans-hepatic approach at the Royal Prince Alfred Hospital from 1983 to 1993. Eleven patients had low-dose rate brachytherapy and four patients had high-dose rate treatment. There were nine males and six females. The median age was 64 years. Other treatment included bypass procedures in two patients, endoscopic stents in 14 patients and external beam irradiation in one patient. The median survival was 12.5 months and 47% of the patients survived 1 year. The only complication reported was cholangitis which was seen in one patient. There did not seem to be any difference in survival or complications between low- and high-dose rate brachytherapy. We conclude that the addition of intraluminal brachytherapy after biliary drainage prolongs survival and is a safe and effective treatment, but patients still have a high rate of local failure, and further studies will be needed to address this problem.  相似文献   
28.
Eleven women with a history of infertility and uterine leiomyomas underwent magnetic resonance (MR) imaging of the pelvis prior to myomectomy. Nine also underwent preoperative pelvic ultrasonography (US), and ten underwent hysterosalpingography. All studies were interpreted prospectively by independent observers. With each imaging modality, the location (one of 11 anatomic segments), size, and appearance of detected uterine leiomyomas were determined and compared with surgical and histologic findings. Among the nine patients who underwent both MR and US, the sensitivity (85%) and accuracy (94%) of MR imaging for abnormal segments was significantly better than that of US (sensitivity = 69%, P = .015; accuracy = 87%, P = .043). For the ten patients who underwent both MR and hysterosalpingography, the sensitivity (91%) and accuracy (96%) of MR imaging was better than that of hysterosalpingography (sensitivity = 18%, P = .0005; accuracy = 72%, P = .0005). The specificities of the three modalities did not significantly differ (100%, 97%, and 98% for MR, US, and hysterosalpingography, respectively). These data suggest that MR imaging is superior to US or hysterosalpingography for preoperatively locating uterine leiomyomas.  相似文献   
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Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals.  相似文献   
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