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191.
192.
Use of 24‐hour ambulatory blood pressure monitoring is strongly endorsed by contemporary hypertension guidelines. The objective of this study was to assess patient perceptions of ambulatory blood pressure testing, tolerability, accessibility, and expense. A convenience sample of 50, consenting patients undergoing ambulatory blood pressure monitoring at the University of Alberta Hypertension Clinic in Edmonton, Canada was studied. A 16‐item structured questionnaire was administered in person or electronically. Questions regarding the tolerability of ambulatory monitoring were evaluated using a 5‐point Likert scale and wait times, expenditures, and willingness to pay were evaluated by direct questioning. Mean age was 53.1 ± 15.4 years, 32 (64%) were female, and 23 (46%) were employed. Mean 24‐hour ambulatory BP was 134 ± 12/79 ± 8 mmHg. Ambulatory monitoring caused discomfort in 40 (80%) patients and disturbed sleep in 39 (78%). Forty‐one (82%) patients perceived that the home (vs pharmacy, primary care clinic, and speciality care clinic) would be the easiest venue to access future testing. On average, patients waited 27.3 ± 23.7 days for testing; they felt that a wait time of 21.3 ± 12.3 days was appropriate. Mean time taken off work was 8.6 ± 10.8 hours. Twelve (24%) patients indicated that they would be willing to pay out‐of‐pocket to undergo testing sooner, at a mean expenditure of $120 ± 69. Nineteen (62%) patients were willing to buy a monitor and felt that a mean purchase cost of $125 ± 89 was appropriate. These findings extend current knowledge of patient perceptions of ambulatory monitoring and may help to refine and optimize future delivery of this essential test.  相似文献   
193.
A child with a complicated medical history that included asplenia acquired an infection with Babesia microti in the summer of 2013 and had not travelled outside of Manitoba. Although the clinical findings were subtle, astute laboratory work helped to reach a preliminary identification of Babesia species, while reference laboratory testing confirmed the diagnosis. Blacklegged ticks (Ixodes scapularis) are known to transmit Borrelia burgdorferi and Anaplasma phagocytophilum in the province; however, the present case represents the first known instance of tick-borne B microti, both in Manitoba and in Canada. The expanding territory of the blacklegged tick increases the relevance of this emerging infection. Clinicians, laboratory medical practitioners and public health officials should be aware of B microti as a potential locally acquired infection in Canada.  相似文献   
194.
Hedin CR  Stagg AJ  Whelan K  Lindsay JO 《Gut》2012,61(2):311-318
Crohn's disease (CD) is an incurable intestinal disorder in which the loss of immune tolerance to the commensal gut microbiota leads to chronic inflammation. The reason this occurs in specific individuals is unclear; however, a genetic predisposition is fundamental and relatives of patients with CD are at significant risk of developing the disease. Knowledge relating to the genetic loci that predispose to CD is accumulating, which raises the possibility of disease prediction and prevention in susceptible populations. However, the genetic basis of CD is complex and genotyping alone is likely to be insufficient to predict disease risk accurately. Specific physiological abnormalities associated with CD, such as increased intestinal permeability and raised faecal calprotectin, are also abnormal in some relatives of patients with CD. The combination of genotypic factors and biomarkers of risk makes the development of models of disease prediction a realistic possibility. Furthermore, enhanced understanding of the genotype and phenotype of the at-risk state in relatives of patients with CD allows the earliest stages in the pathogenesis of CD to be investigated and may allow intervention to prevent disease onset. This article reviews current knowledge of the at-risk phenotype in relatives of patients with CD and focuses on the implications for the design of future studies.  相似文献   
195.

Aims/hypothesis  

Diabetic ketoacidosis is a potentially life-threatening complication of diabetes and has a strong relationship with HbA1c. We examined how socioeconomic group affects the likelihood of admission to hospital for diabetic ketoacidosis.  相似文献   
196.
Context: Recent studies on the mechanism of action (MOA) of bone-active drugs have rekindled interest in how to present and interpret dynamic histomorphometric parameters of bone remodeling. Objective: We compared the effects of an established anabolic agent, teriparatide (TPTD), with those of a prototypical antiresorptive agent, zoledronic acid (ZOL). Design: This was a 12-month, randomized, double-blind, active-comparator controlled, cross-sectional biopsy study. Setting: The study was conducted at 12 U.S. and Canadian centers. Subjects: Healthy postmenopausal women with osteoporosis participated in the study. Interventions: Subjects received TPTD 20 μg once daily by sc injection (n = 34) or ZOL 5 mg by iv infusion at baseline (n = 35). Main Outcome Measures: The primary end point was mineralizing surface/bone surface (MS/BS), a dynamic measure of bone formation, at month 6. A standard panel of dynamic and static histomorphometric indices was also assessed. When specimens with missing labels were encountered, several methods were used to calculate mineral apposition rate (MAR). Serum markers of bone turnover were also measured. Results: Among 58 subjects with evaluable biopsies (TPTD = 28; ZOL = 30), MS/BS was significantly higher in the TPTD group (median: 5.60 vs. 0.16%, P < 0.001). Other bone formation indices, including MAR, were also higher in the TPTD group (P < 0.05). TPTD significantly increased procollagen type 1 N-terminal propeptide (PINP) at months 1, 3, 6, and 12 and carboxyterminal cross-linking telopeptide of collagen type 1 (CTX) from months 3 to 12. ZOL significantly decreased PINP and CTX below baseline at all time points. Conclusions: TPTD and ZOL possess fundamentally different mechanisms of action with opposite effects on bone formation based on this analysis of both histomorphometric data and serum markers of bone formation and resorption. An important mechanistic difference was a substantially higher MS/BS in the TPTD group. Overall, these results define the dynamic histomorphometric characteristics of anabolic activity relative to antiresorptive activity after treatment with these two drugs.  相似文献   
197.
Described in detail is the molecular epidemiology of wild-type 1 poliovirus circulation in Ghana between 1995-2008, following the implementation of a surveillance system for cases of acute flaccid paralysis and poliovirus infection. Molecular phylogenetic analysis combined with a detailed evaluation of epidemiological indicators revealed that the geographical and temporal circulation of wild-type poliovirus in Ghana was determined by the quality of the implementation of global eradication strategies. The transmission of "indigenous" wild-type 1 poliovirus was eliminated in 1999. However, a drastic reduction in national immunization campaigns resulted in the importation in 2003 and 2008 of wild-type 1 poliovirus from neighboring countries. Both outbreaks were promptly interrupted following resumption of immunization activities. The results detailed here provide scientific evidence that supports the feasibility of polio eradication in Central West Africa, one of the remaining endemic areas for the disease, provided that comprehensive immunization campaigns and sensitive surveillance systems are in place.  相似文献   
198.
199.
Left ventricular systolic dysfunction in patients with severe aortic stenosis (AS) is associated with poor outcome. This analysis was designed primarily to describe the clinical course of a large series of consecutive patients with severe AS and low ejection fraction (EF) (<40%) who, because of high surgical risk, were referred for transcatheter aortic valve implantation consideration. A cohort of 270 patients with severe AS and low EF (<40%) who were referred to participate in a clinical trial of transcatheter aortic valve implantation was studied. Clinical, hemodynamic, and periprocedural complications and follow-up mortality data were collected and compared between patients with low mean transvalvular gradients (≤40 mm Hg, n = 170 [63%]) and high transvalvular gradients (>40 mm Hg, n = 100 [37%]). Patients with low gradients were younger (mean age 79.8 ± 9.1 vs 83.8 ± 7.7 years, p <0.001) and had higher incidences of coronary artery disease and renal failure. Mean aortic valve area was larger (0.73 ± 0.23 vs 0.53 ± 0.18 cm(2), p <0.001), while mean EF (26.4 ± 6.9% vs 30.5% ± 6.6%, p <0.001), cardiac output (3.7 ± 1.1 vs 4.1 ± 1.3 L/min, p = 0.04), and cardiac index (1.9 ± 0.5 vs 2.1 ± 0.6 L/min/m(2), p = 0.04) were lower in patients with lower gradients compared to those with higher gradients, respectively. Mortality was higher in patients with low gradients (53.8%) at a mean follow-up of 151 days compared to those with high gradients (41%) at a mean follow-up of 256 days (p = 0.01). In conclusion, patients with severe AS and low EF with low transvalvular gradients are at higher risk for worse outcomes compared to patients with high transvalvular gradients. Surgery or transcatheter aortic valve implantation treatment and high baseline transvalvular gradient are associated with EF improvement.  相似文献   
200.
Vascular complications (VCs) occur in 3% to 8% of percutaneous coronary interventions (PCIs). However, only a portion of patients who experience VCs bleed significantly. The aim of this study was to assess the covariates associated with the amount of blood loss in patients experiencing postprocedural VCs as well as the effect of the degree of blood loss on long-term mortality. Overall, 7,718 unselected patients who underwent PCI through femoral access were evaluated. Those experiencing VCs were identified and stratified with regard to the degree of hematocrit (HCT) decrease after the procedure. In total, 444 patients (5.8%) had VCs. Compared to those without VCs, patients with VCs were older and had more extensive co-morbidities. Severe blood loss was most frequent in those who had vascular perforation requiring surgical repair or in those who had retroperitoneal bleeding. Overall, <25% of patients with hematoma had severe blood loss. The raw 1-year mortality was doubled in patients with minimal or moderate HCT decrease and was tripled in those with severe decreases in HCT. Similarly, the rate of definite stent thrombosis was tripled in patients with VCs and moderate or severe decreases in HCT. After adjustment, only patients with VCs and the greater HCT decreases had an increased risk for death at 1 year (hazard ratio 1.80, 95% confidence interval 1.03 to 3.14). Independent predictors of severe HCT decrease included age, female gender, glycoprotein IIb/IIIa inhibitor use, and activated clotting time peak. Bivalirudin and closure devices were independently associated with less frequent severe HCT decrease. In conclusion, VCs do not entail an increased risk for death at 1 year unless associated with severe blood loss. The use of bivalirudin and closure devices seems to reduce the risk for such complications.  相似文献   
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