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81.
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   
82.
83.
Significance of omental evisceration in abdominal stab wounds   总被引:1,自引:0,他引:1  
Over a 4 year period, 115 patients presented to Parkland Memorial Hospital with omental evisceration after a stab wound to the abdomen. All patients underwent exploratory celiotomy. Serious abdominal injuries were found in 86 patients (75 percent), and half of these had two or more organs injured. The injury rate in patients with omental herniation was three times that of patients with simple stab wounds. No preoperative evaluation technique was reliable in identifying patients without injury. There were no deaths and only a 7 percent incidence of minor complications in patients who underwent negative exploration. Our data suggest that omental evisceration in a patient with an abdominal stab wound portends potentially serious injury and supports the policy of expeditious celiotomy.  相似文献   
84.
The role of arteriography in asymptomatic patients with penetrating extremity wounds in proximity to major vessels is controversial. This prospective study was designed to evaluate a precise definition of proximity, determine the incidence of positive arteriograms, and correlate angiographic interpretation with operative findings. Proximity was defined as any wound located within 1 cm of a major vessel. Excluded were patients with a pulse deficit, bruit, thrill, history of arterial hemorrhage, expanding hematoma, nerve deficit, fracture, or significant soft-tissue injury. One hundred sixty arteriograms were performed in 146 patients. One hundred forty-three (89.4%) were true-negatives. Seventeen (10.6%) were suggestive of injury. These included seven (4.4%) true-positive arteriograms, six (3.8%) false-positive studies, and four (2.5%) positive arteriograms in patients who were not operated upon. The angiographic report correlated with operative findings in five (38.5%) of 13 patients. These data confirm the low incidence (4.4%) of vascular injury in asymptomatic patients. The use of extremity angiography when proximity is the sole indication in an asymptomatic patient with a normal vascular examination must be questioned.  相似文献   
85.
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   
86.
Lead poisoning from retained missiles. An experimental study.   总被引:1,自引:0,他引:1       下载免费PDF全文
The problem of lead poisoning from bullets has been investigated by surgically implanting discs of lead, each enriched in a different natural isotope, into the tissue of two mongrel dogs and monitoring by mass spectrometry the release of the lead into each animal's blood over the course of 3 years. Lead placed in the knee underwent vigorous attack by the synovial fluid, far in excess of what would be expected from corrosion theory, and reached a maximum concentration in blood 4-6 months after operation. Thereafter, lead concentration exponentially declined as the remaining fragments became encapsulated. The disc placed in muscle was sparingly soluble immediately following implantation. It is concluded that the greatest danger of lead poisoning from an injury involving many fragments having collectively a large surface area will occur within a month, and that the cases of lead poisoning resulting from bullets in joints that occur 5 or more years after injury are caused by continual wear of metal on a joint surface, storage of lead so released in the skeleton, and its subsequent resorption during a change in osteocyte activity.  相似文献   
87.
88.
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic pulmonary infection/inflammation which leads to respiratory failure. The presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has previously been observed in the sera of patients with CF. In view of the known relationship of ANCA with primary vasculitis and of their putative pathogenetic role in these disorders, we studied the presence, specificity and isotype of ANCA and their clinical associations in 66 adult CF patients. None of the 66 CF samples had autoantibodies to the major ANCA antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples contained IgG and 55/66 (83%) IgA, autoantibodies to bactericidal/permeability increasing protein (BPI), a recently characterized ANCA specificity. All the IgA anti-BPI-positive samples were also IgG anti-BPI-positive. The autoantibody specificity was confirmed by inhibition assay and immunoblotting of CF sera against a neutrophil granule preparation. Furthermore, in this cross-sectional study, anti-BPI levels were inversely correlated with the observed reductions in FEV1 and FVC (IgA anti-BPI and FEV1: r = 0.508, <it>p</it> &lt; 0.0001), and both IgG and IgA anti-BPI levels were higher in CF patients with secondary vasculitis (<it>n</it> = 6) than in those without (<it>p</it> &lt; 0.05). ANCA with specificity for BPI were present in the majority of CF sera in this study and autoimmune processes may be associated with the development of pulmonary injury in CF.   相似文献   
89.
Felty's syndrome (FS) (rheumatoid arthritis with neutropenia and splenomegaly) has a poor prognosis, largely because of the high risk of severe infection. Granulocyte colony-stimulating factor (G-CSF) is an emerging treatment for chronic neutropenia. We prospectively monitored its use in eight patients with recurrent infections or who required joint surgery. Significant side-effects were documented in five, including nausea, malaise, generalized joint pains, and in one patient, a vasculitic skin rash. In two patients treatment had to be stopped, and in these cases G-CSF had been started at full vial dosage (300 micrograms/ml filgrastim or 263 micrograms/ml lenograstim) alternate days or daily. G-CSF treatment was continued in three patients by restarting at reduced dose, and changing the proprietary formulation. G- CSF raised the neutrophil count, reduced severe infection, and allowed surgery to be performed. A combined clinical and laboratory index suggested that long-term treatment (up to 3.5 years) did not exacerbate the arthritis. Once on established treatment, it may be possible to use smaller weekly doses of G-CSF to maintain the same clinical benefit. One of the three patients whose FS was associated with a large granular T-cell lymphocytosis showed a reduction in this subset of lymphocytes during G-CSF treatment.   相似文献   
90.
Growth factors have been identified as the primary cause of osteoinduction in bone healing. Transforming growth factor beta (TGF- beta) has been shown to promote bone formation and is present in bone in high quantities. The aims of the present study were to isolate TGF- beta from human bone, demonstrate its biologic activity, and analyze the effects of conventional sterilization techniques on activity. Bone, obtained from femoral heads of five patients (mean age, 70 years) was ground, demineralized, and freeze-dried, and samples from each patient were divided into three groups: no treatment, sterilization with 1.60 to 1.94 Mrad of 60Co irradiation, and sterilization with ethylene oxide (ETO). Carrier-free recombinant TGF-beta control was also treated and was totally inactivated by ETO but not by irradiation (p < 0.01). TGF- beta activity in demineralized bone was not significantly diminished (p > 0.1) by either sterilization procedure, and substantial amounts of active TGF-beta were recovered in all bone samples: 1.04 +/− 0.77 ng per mg of protein in irradiated samples, 0.67 +/− 0.26 ng per mg in ETO- treated samples, and 1.04 +/− 0.33 in untreated samples, respectively (mean +/− SD). Although a recent report demonstrated that the osteoinductive activity of bone morphogenetic protein in bone powder is diminished considerably by ETO and by 2.5 Mrad of irradiation sterilization of bone powder, these data demonstrate that TGF-beta activity, with its osteoinductive properties, was not destroyed in more coarsely ground, demineralized bone by ETO or by lower doses of irradiation. These findings support the use of human bone allografts in clinical instances involving impaired bone formation.  相似文献   
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