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91.
OBJECTIVE--To determine whether particular sociodemographic characteristics of patients with stable angina affected their general practitioners' (GPs') decisions to refer them for revascularisation assessment. DESIGN--Postal questionnaire survey. SETTING--Collaborative survey by the departments of public health medicine in each of the four health boards in Northern Ireland, serving a total population of 1.5 million. SUBJECTS--All (962) GPs. MAIN MEASURES--The relation between GPs' referral decisions and patients' age, sex, employment status, home circumstances, smoking habits, and obesity. RESULTS--541 GPs replied (response rate 56%). Most were "neutral" towards a patient's sex (428, 79%), weight (331, 61%), smoking habit (302, 56%), employment status (431, 80%), and home circumstances (408, 75%) in making decisions about referral. In assigning priority for surgery most were neutral towards the patient's sex (459, 85%), employment status (378, 70%), and home circumstances (295, 55%). However, most GPs (518, 95%) said that younger patients were more likely to be referred, and a significant minority were less likely to refer patients who smoked (202, 37%) and obese patients (175, 32%) and more likely to refer employed patients (97, 18%) and those with dependents (117, 22%) (compared with patients with otherwise comparable clinical characteristics); these views paralleled the priority which GPs assigned these groups. The stated likelihood of referral of young patients was independent of the GPs' belief in ability to benefit from revascularisation, but propensity to refer and perception of benefit were significantly associated for all other patient characteristics. CONCLUSION--GPs' weighting of certain characteristics in reaching decisions about referral for angiography is not uniform and may contribute to unequal access to revascularisation services for certain patient groups.  相似文献   
92.
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   
93.
Farnesyl transferase inhibitors (FTIs) serve to specifically inhibit farnesyl isoprenoid lipid modification of proteins. Although originally developed as anti-Ras oncoprotein drugs, it now appears that these compounds function independently of Ras. FTIs have been shown to inhibit transformation by a variety of mechanisms, including apoptosis involving cytochrome c release from mitochondria.Tamoxifen exhibits both anti-estrogenic and estrogenic properties and is widely used as an estrogen antagonist for the treatment of estrogen receptor (ER) positive human breast tumors. Tamoxifen can induce ER-dependent apoptosis in human breast tumor cells by a mechanism involving the Bcl2/mitochondrial arm of the apoptotic machinery. Since tamoxifen and FTIs may stimulate distinct components of the mitochondrial-based apoptotic machinery, we reasoned that their effects might be synergistic.Here we show that anti-estrogens and an FTI (FTI-277) synergize to inhibit cell growth and enhance cell death in ER positive, human breast tumor cell lines. However, the drugs exhibited only additive effects on an ER negative cell line. Analysis of treated ER positive T-47D cells demonstrated that a synergistic increase in apoptosis was induced, as measured by increased caspase 3 activity. Thus, tamoxifen and FTIs may synergize to promote apoptotic cell death in ER positive human breast tumor cells.  相似文献   
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Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images.  相似文献   
96.
Radiologically guided balloon catheters were used to dilate 94 gastrointestinal strictures in 92 patients over a 6-year period. Fifty strictures were esophageal and 44 nonesophageal (22 gastroenterostomies, 11 antral-pyloric strictures, four colorectal strictures, four enteroenterostomies, and three miscellaneous strictures). Factors influencing the success of stricture intubation included patient age, stricture location (esophageal vs. nonesophageal and proximal vs. distal esophageal), and association with a surgical anastomosis. Malignancy was associated with greater postdilation irregularity and a smaller increase in stricture diameter, as measured radiographically. Procedural failures occurred in 8% of cases (2% of esophageal and 30% of nonesophageal lesions). Two small, asymptomatic mucosal tears were seen after dilation (one esophageal and one colonic); no other procedural complications occurred. Following successful dilation, 16 patients (17%; six with esophageal and ten with non-esophageal strictures) had recurrence of symptoms during short-term (30-day) follow-up.  相似文献   
97.
Mann  LC; Hawes  DR; Ghods  M; Bednar  EJ; Potchen  EJ 《Radiology》1987,164(1):121-122
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography.  相似文献   
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100.
Examination of 536 female mesostigmatid mites of 177 samples collected from Bandicota bengalensis in Rangoon, Burma revealed 6 species present: Laelaps echidnina, L. nuttalli, L. myonyssognathus, Laelaps sp. A and B of Allred, 1970, and Liponyssoides muris, all of which were elsewhere reported from Rattus spp. in Rangoon. Analysis of variation in abundance by season found no significant differences except for Liponyssoides muris which was most common in the hot dry season, March through May.  相似文献   
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