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101.
BACKGROUND: Uterine papillary serous carcinoma (UPSC) shares common pathologic, genetic, and clinical features with other serous cancers of müllerian origin. The most common histologic type of ovarian tumor associated with BRCA mutations is papillary serous. Because of these histologic similarities, we postulated that, in some cases, UPSC may be a manifestation of a field defect in BRCA1 carriers, which also includes ovarian carcinoma, fallopian tube carcinoma, and primary peritoneal carcinoma. METHODS: Fifty-six living patients with UPSC were contacted through their treating physicians and agreed to a family history interview and to provide a blood specimen for BRCA testing. The protein truncation test was used to detect mutations in exons 10 and 11 of BRCA1 and in exon 11 of BRCA2. The presence of four common mutations was assessed by PCR-based specific assays. RESULTS: A high proportion of patients had a past history of breast cancer (11%) or a first-degree relative with breast cancer (29%). Four patients were from families with site-specific hereditary breast cancer. However, there was no clear example of the hereditary breast-ovarian cancer syndrome, and none of the 56 patients was found to carry a BRCA1 or BRCA2 mutation. CONCLUSIONS: BRCA mutations do not appear to predispose to UPSC and this type of cancer does not appear to be a manifestation of the classical hereditary breast-ovarian cancer syndrome. The observed association between UPSC and breast cancer may be due to the presence of mutations in other cancer predisposing genes.  相似文献   
102.
103.
Multiple primary cancers are characteristic of hereditary cancer syndromes. A familial association between breast and thyroid cancer has been suggested, but a genetic basis for this association has not yet been established. To determine the extent to which double primary cancers of the breast and thyroid are due to common hereditary factors, we conducted a registry- and hospital-based study in Ontario and Quebec. We obtained family histories of 74 women diagnosed with both cancer of the breast and thyroid before 70 years of age. Cancer histories were obtained for the 533 first-degree relatives of these women. The observed cancer rate in the relatives was compared with the expected number, based on age-standardized Canadian cancer incidence rates, and relative risks were estimated. A total of 87 cancers were observed in the relatives, compared to 93.7 expected cancers, giving a relative risk of 0.9 (95% confidence interval (CI): 0.7–1.1). The risk for breast cancer was 1.1 (95% CI: 0.6–1.7) and the risk for thyroid cancer was 0.7 (95% CI: 0–3.8). Blood samples were collected on 53 patients for mutational analysis of the BRCA1, BRCA2, and PTEN genes. One woman was found to be a carrier of a BRCA1 mutation (exon 11 3227delT). Our findings do not support the hypothesis that a significant proportion of double primary cancers of the breast and thyroid are due to hereditary factors.  相似文献   
104.
输血和大多数临床治疗技术一样,存在着一定的风险,输血风险主要由免疫性输血风险和输血感染性风险两大类相关的安全问题。20世纪80年代开始,由于艾滋病的发现迫使输血相关的安全问题更进一步成为公众关注的焦点。随着输血用血医学的不断发展,在已经获得很好治疗效果的同时,如何更加科学的安全用血是挑战当今公共卫生事业发展的一项大课题。  相似文献   
105.
Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging.  相似文献   
106.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis.  相似文献   
107.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification.  相似文献   
108.
109.
Obstructive sleep apnea: diagnosis with ultrafast CT   总被引:8,自引:0,他引:8  
Galvin  JR; Rooholamini  SA; Stanford  W 《Radiology》1989,171(3):775-778
Patients with sleep-disordered breathing often have physiologic and anatomic abnormalities of the upper airway that are demonstrable while awake. An ultrafast computed tomographic (CT) scanner was used to measure the oropharyngeal and nasopharyngeal cross-sectional areas of 11 patients with obstructive sleep apnea. Twenty-four healthy volunteers served as control subjects. The percentage of change in cross-sectional area during quiet tidal breathing was used as a measure of airway compliance. Compared with weight-matched control subjects, patients with obstructive sleep apnea had smaller oropharyngeal airways (40.4 vs 177.8 mm2) (P less than .001) and smaller nasopharyngeal airways (31.3 vs 134.2 mm2) (P less than .001). In addition, their oropharyngeal airways were significantly more compliant (75% vs 27%) (P less than .001). Patients with obstructive sleep apnea are characterized by a small, collapsible oropharyngeal airway and by nasopharyngeal airway narrowing. These abnormalities can cause sleep-disordered breathing. Ultrafast CT scanning allows rapid, noninvasive assessment of airway variables.  相似文献   
110.
Percutaneous drainage access: a simplified coaxial technique   总被引:1,自引:0,他引:1  
We describe an access technique that we have used in 150 nephrostomy and biliary drainage procedures and for access to some abscesses and viscera. The system provides safe coaxial access with a 22-gauge removable hub needle, which then acts as a guide wire and is replaced by an 18-gauge cannula. A major advantage is that only one guide wire is used (0.038-inch) for the entire drainage procedure. No significant complications have occurred to date with this method.  相似文献   
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