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901.
BACKGROUND & AIMS: A population-based cohort from Copenhagen County comprising 1160 patients diagnosed with ulcerative colitis between 1962 and 1987 was followed-up until 1997 to describe survival and cause-specific mortality. METHODS: Observed vs. expected deaths were presented as standardized mortality ratio (SMR) with exact 95% confidence intervals (CI) calculated by using individually registered person-years at risk and Danish 1995 mortality rates. Cumulative survival curves were calculated. RESULTS: A total of 261 deaths occurred, not significantly different from the expected number of 249 (SMR, 1.05; 95% CI, 0.92-1.19). The median age at death among men was 70 years (range, 6-96 years) and among women 74 years (range, 25-96 years). Twenty-five deaths (9.6%) were caused by complications to ulcerative colitis, mostly infectious and cardiovascular postoperative complications. Patients older than 50 years of age at diagnosis and with extensive colitis showed an increased mortality within the first 2 years because of ulcerative colitis-associated causes. The mortality from colorectal cancer was not increased and that of cancer in general was significantly lower than expected: 50 vs. 71 (SMR, 0.70; 95% CI, 0.52-0.93). A significantly increased mortality from pulmonary embolism and pneumonia was found. Among women only, death from genitourinary tract diseases and suicide was significantly increased. CONCLUSIONS: Despite an overall normal life expectancy for patients with ulcerative colitis, patients >50 years of age and with extensive colitis at diagnosis had increased mortality within the first 2 years after diagnosis, owing to colitis-associated postoperative complications and comorbidity.  相似文献   
902.
Background: Non‐Q wave mvocardial infarction (NQMI) and unstable angina (UAP) have similar clinical presentations and similar ST‐T changes on the electrocardiogram. The purpose of this study was to assess whether changes in QT interval might help differentiating between these entities. Methods: The QT intervals of 52 patients hospitalized with NQMI were compared to those of 52 patients hospitalized for UAP. All patients had repeated ECG for at least 4 days. Results: Maximal QTc in patients with NQMI was significantly longer than in patients with UAP (475 vs 439 ms, P < 0.0001). QTc on the admission ECG was 450 ms in patients with NQMI compared to 417 ms in UAP P < 0.005). QTc > 460 ms was present in 48% patients with NQMI and in 19% of UAP patients. Maximal QT prolongation was observed within 36 hours of admission with return to normal within 96 hours. QT dispersion was within normal range, being longer in patients with NQMI than patients with UAP (55 vs 43 ms, P < 0.003). QT prolongation was not associated with increased frequency of arrhythmia. The cause of QT prolongation in NQMI may be related to the damage of subendocardial layer exposing the M cells layer which markedly prolong action potential duration. Conclusion: Transient QT prolongation is observed in about half of patients with NQMI. These ECG changes may help differentiating between patients with NQMI and UAP already on admission. A.N.E. 2002;7(4):343–348  相似文献   
903.
BACKGROUND AND OBJECTIVES: West Africa is a highly endemic area for viral infections. The prevalence of five viral markers was determined in Ghanaian blood donors. MATERIALS AND METHODS: Replacement and volunteer blood donors were screened using enzyme immunoassays (EIAs) for hepatitis B surface antigen (HBsAg), human immunodeficiency virus antibodies (anti-HIV), HIV p24 antigen, human T-cell lymphocytotrophic virus-I and -II antibodies (anti-HTLV-I/II) and hepatitis C virus antibodies (anti-HCV). RESULTS: HBsAg was present at an equally high frequency (15%) in young volunteer (median age 18 years) and older replacement (median age 33 years) blood donors. In contrast, the prevalence of anti-HIV and anti-HCV was significantly higher in replacement blood donors (2.4 and 0.3%, respectively, P < 0.001). HCV RNA was detected in 74 or 55% of seropositive donors, depending on the confirmatory criteria used. No p24 antigen-positive/anti-HIV-negative donations were found. The prevalence of HTLV-I/II was generally low (0.5%). CONCLUSION: All blood donations should be screened for hepatitis B virus (HBV), HIV and HCV markers.  相似文献   
904.
OBJECTIVE: To assess health care practitioners' ability to correctly measure the QT interval, and to identify factors and medications that may increase the risk of QT-interval prolongation and torsades de pointes. DESIGN: A cross-sectional analysis of a survey administered between April 2002 and March 2003. PARTICIPANTS AND SETTING: Health care practitioners attending Grand Rounds Conferences at 6 academic institutions in the United States in internal medicine and psychiatry and at 6 community hospitals in the same geographical areas as the academic institutions. INTERVENTION: Anonymous, self-administered questionnaire that included 20 questions on the QT interval. MEASUREMENTS AND MAIN RESULTS: Of approximately 826 attendees, 517 (63%) completed the survey. Of about 608 attendees of internal medicine conferences, 371 (61%) responded, and of about 208 attendees of psychiatry conferences, 146 (67%) responded. Of a total number of 20 questions, the median number of correct answers for the whole group was 10 (interquartile range 7-13). The median number of correct answers for internists was 12 (interquartile range 9-13), for psychiatrists 10 (interquartile range 7-13), and for other specialists 10 (interquartile range 5-13). Respondents who graduated between 1990 and 1999 and academicians performed significantly better overall than other respondents. Of the 517 respondents, 224 (43%) measured the QT interval correctly. Physicians in training and academicians were more likely to measure the QT interval correctly. CONCLUSION: The majority of health care practitioners cannot correctly measure the QT interval and cannot correctly identify factors and medications that can prolong the QT interval. Our findings suggest that greater attention to the QT interval is warranted to ensure safer use of QT prolonging medications.  相似文献   
905.
906.

Background

Contemporary reconsideration of diagnostic N-terminal pro–B-type natriuretic peptide (NT-proBNP) cutoffs for diagnosis of heart failure (HF) is needed.

Objectives

This study sought to evaluate the diagnostic performance of NT-proBNP for acute HF in patients with dyspnea in the emergency department (ED) setting.

Methods

Dyspneic patients presenting to 19 EDs in North America were enrolled and had blood drawn for subsequent NT-proBNP measurement. Primary endpoints were positive predictive values of age-stratified cutoffs (450, 900, and 1,800 pg/ml) for diagnosis of acute HF and negative predictive value of the rule-out cutoff to exclude acute HF. Secondary endpoints included sensitivity, specificity, and positive (+) and negative (?) likelihood ratios (LRs) for acute HF.

Results

Of 1,461 subjects, 277 (19%) were adjudicated as having acute HF. The area under the receiver-operating characteristic curve for diagnosis of acute HF was 0.91 (95% confidence interval [CI]: 0.90 to 0.93; p < 0.001). Sensitivity for age stratified cutoffs of 450, 900, and 1,800 pg/ml was 85.7%, 79.3%, and 75.9%, respectively; specificity was 93.9%, 84.0%, and 75.0%, respectively. Positive predictive values were 53.6%, 58.4%, and 62.0%, respectively. Overall LR+ across age-dependent cutoffs was 5.99 (95% CI: 5.05 to 6.93); individual LR+ for age-dependent cutoffs was 14.08, 4.95, and 3.03, respectively. The sensitivity and negative predictive value for the rule-out cutoff of 300 pg/ml were 93.9% and 98.0%, respectively; LR? was 0.09 (95% CI: 0.05 to 0.13).

Conclusions

In acutely dyspneic patients seen in the ED setting, age-stratified NT-proBNP cutpoints may aid in the diagnosis of acute HF. An NT-proBNP <300 pg/ml strongly excludes the presence of acute HF.  相似文献   
907.

Background

This review evaluated the efficacy and safety of a combination therapy comprising a sodium-glucose cotransporter type 2 inhibitor (SGLT2i) and dipeptidyl peptidase-4 inhibitor (DPP4i) in type 2 diabetes.

Methods

A literature search through to May 2017 was carried out of PubMed, Embase and the Cochrane Central Register of Controlled Trials. Studies were eligible if they were randomized controlled trials (RCTs) comparing SGLT2i plus DPP4i (SGLT2i/DPP4i) against DPP4i ± placebo or SGLT2i ± placebo and published in English. The primary outcome was change in HbA1c from baseline.

Results

Eight RCTs comparing SGLT2i/DPP4i and DPP4i, and five RCTs comparing SGLT2i/DPP4i and SGLT2i, with three RCTs involving both comparisons, were included in the present review. SGLT2i/DPP4i resulted in a greater mean HbA1c reduction [weighted mean difference (WMD]): ?0.62%] than did DPP4i alone, which was a much less marked reduction (WMD: ?0.35%) than with SGLT2i alone. Also, significant differences in body weight loss from baseline were observed only with SGLT2i/DPP4i vs. DPP4i, but not vs. SGLT2i. The risk of hypoglycaemic events was low and similar between treatment groups. When subjects were stratified based on baseline HbA1c, any reduction by SGLT2i/DPP4i in relation to DPP4i was proportional to baseline HbA1c levels. However, compared with SGLT2i, HbA1c reductions with SGLT2i/DPP4i were modest regardless of baseline HbA1c.

Conclusion

Combination therapy with SGLT2i and DPP4i is both efficacious and safe. In particular, a marked additional glucose-lowering effect is evident when SGLT2i is combined with or added to DPP4i, and not vice versa. However, baseline HbA1c determined the additional glucose-lowering effects of SGLT2i in combined treatment with DPP4i.  相似文献   
908.
909.
910.
研究证明基于囊胚期活检和全基因组分析技术的"第二代植入前遗传学筛查(PGS)"可以显著提高IVF治疗的临床结局。目前认为囊胚期活检是PGS活检的最佳时间,也是第二代PGS采用的活检方法。具体为通过单细胞全基因组扩增技术使样本达到可检测的量,再利用微阵列技术、高通量测序技术完成全基因组检测。除了技术方面的改进,第二代PGS还应在适用人群的选择方面综合考虑不孕者胚胎非整倍体的发生率和可用于移植的囊胚数2个方面,PGS的最适宜人群应该是排除了内膜因素的影响后其染色体异常发生率较高、同时可移植胚胎数较多者。  相似文献   
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