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71.
INTRODUCTION: Ventricular oversensing (OS) of respirophasic noise transients may cause spurious detections and therapies and pacing inhibition among patients with implantable cardioverter defibrillators (ICDs). The incidence of OS and its relationship to clinical variables and ICD system design are unknown. METHODS AND RESULTS: Three hundred twenty-nine patients performed provocative respiratory maneuvers at rest during intrinsic rhythm and continuous ventricular pacing. OS resulting in spurious ventricular detections was provoked in 3 (0.9%) of 329 patients during intrinsic rhythm and 34 (10.3%) of 329 during pacing. Noise transients not recognized and marked as sensed events, but visually evident on the local endocardial ventricular electrogram, were provoked in an additional 23 (7.0%) of 329 patients. Multivariate logistic regression identified history of spontaneous OS (P < 0.0005, odds ratio 9.7, 95% confidence interval [CI] 1.9 to 50.0), automatic gain control device (P < 0.0005, odds ratio 5.3, 95% CI 2.6 to 10.8) or integrated bipolar lead (P = 0.05, odds ratio 2.6, 95% CI 1.0 to 7.25), and male gender (P = 0.008, odds ratio 3.7, 95% CI 1.2 to 11.1) as predictive of provocable OS. Spontaneous OS resulting in spurious ventricular detections and therapies occurred in 12 (3.6%) patients during follow-up. Eleven of 12 spontaneous episodes occurred in male patients during ventricular pacing; 11 of 12 patients had automatic gain control devices and integrated bipolar leads. CONCLUSION: OS is commonly provoked in ICD patients during ventricular pacing and may occur spontaneously, causing spurious tachyarrhythmia therapies and pacing inhibition. Differences in the incidence of spontaneous and provoked OS between ICD systems can be explained on the basis of unique features of automatic sensing systems and sensing lead design.  相似文献   
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Background

Little is known about depression in older people in sub-Saharan Africa, the associated impact of HIV, and the influence on health perceptions.

Objectives

Examine the prevalence and correlates of depression; explore the relationship between depression and health perceptions in HIV-infected and -affected older people.

Methods

In 2010, 422 HIV-infected and -affected participants aged 50+ were recruited into a cross-sectional study. Nurse professionals interviewed participants and a diagnosis of depressive episode was derived from the Composite International Diagnostic Interview (Depression module) using the International Classification of Diseases diagnostic criteria and categorised as major (MDE) or brief (BDE).

Results

Overall, 42.4% (n=179) had a depressive episode (MDE: 22.7%, n=96; BDE: 19.7%, n=83). Prevalence of MDE was significantly higher in HIV-affected (30.1%, 95% CI 24.0–36.2%) than HIV-infected (14.8%, 95% CI 9.9–19.7%) participants; BDE was higher in HIV-infected (24.6%, 95% CI 18.7–30.6%) than in HIV-affected (15.1%, 95% CI 10.3–19.8%) participants. Being female (aOR 3.04, 95% CI 1.73–5.36), receiving a government grant (aOR 0.34, 95% CI 0.15–0.75), urban residency (aOR 1.86, 95% CI 1.16–2.96) and adult care-giving (aOR 2.37, 95% CI 1.37–4.12) were significantly associated with any depressive episode. Participants with a depressive episode were 2–3 times more likely to report poor health perceptions.

Limitations

Study limitations include the cross-sectional design, limited sample size and possible selection biases.

Conclusions

Prevalence of depressive episodes was high. Major depressive episodes were higher in HIV-affected than HIV-infected participants. Psycho-social support similar to that of HIV treatment programmes around HIV-affected older people may be useful in reducing their vulnerability to depression.  相似文献   
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Background

Laparoscopic hernia repair is used widely for the repair of incisional hernias. Few case studies have focussed on purely ‘incisional’ hernias. This multicentre series represents a collaborative effort and employed statistical analyses to provide insight into the factors predisposing to recurrence of incisional hernia after laparoscopic repair. A specific hypothesis (ie, laterality of hernias as well as proximity to the xyphoid process and pubic symphysis predisposes to recurrence) was also tested.

Methods

This was a retrospective study of all laparoscopic incisional hernias undertaken in six centres from 1 January 2004 to 31 December 2010. It comprised a comprehensive review of case notes and a follow-up using a structured telephone questionnaire. Patient demographics, previous medical/surgical history, surgical procedure, postoperative recovery, and perceived effect on quality of life were recorded. Repairs undertaken for primary ventral hernias were excluded. A logistic regression analysis was then fitted with recurrence as the primary outcome.

Results

A total of 186 cases (91 females) were identified. Median follow-up was 42 months. Telephone interviews were answered by 115/186 (62%) of subjects. Logistic regression analyses suggested that only female sex (odds ratio (OR) 3.53; 95% confidence interval (CI) 1.39–8.97) and diabetes mellitus (3.54; 1–12.56) significantly increased the risk of recurrence. Position of the defect had no statistical effect.

Conclusions

These data suggest an increased risk of recurrence after laparoscopic incisional hernia repair in females and subjects with diabetes mellitus. These data will help inform surgeons and patients when considering laparoscopic management of incisional hernias. We recommend a centrally hosted, prospectively maintained national/international database to carry out additional research.  相似文献   
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Observations on idiopathic proctitis   总被引:5,自引:2,他引:5       下载免费PDF全文
This paper presents the natural history of idiopathic proctitis and concludes that this disease and idiopathic procto-colitis are two manifestations of one disease differing only in the extent of the colon involved.  相似文献   
78.
OBJECTIVE: To determine whether mode of delivery or the use of maternal or neonatal antiretroviral prophylaxis influence the age when HIV-1 can first be detected in infected infants, particularly the probability of detection at birth. METHODS: In a collaboration between four multicentre studies, data on 422 HIV-1 infected infants who were assessed by HIV-1 DNA PCR or cell culture before 14 days of age were analysed. Weibull mixture models were used to estimate the cumulative proportion of infants with detectable levels of HIV-1 according to use of maternal/neonatal antiretroviral therapy (mainly zidovudine monotherapy) and mode of delivery. RESULTS: HIV-1 was detected in 162 infants (38%) when they were first tested, at a median age of 2 days. At birth, it was estimated that 36% [95% confidence interval (CI), 31-41%] of infants have levels of virus that can be detected by DNA PCR or cell culture. This percentage was not associated with either mode of delivery (35% for vaginal delivery versus 40% for cesarean section delivery; P = 0.4) or the use of maternal or neonatal antiretroviral prophylaxis. Among infants with undetectable levels of HIV-1 at birth, the median time to viral detectability was estimated to be 14.8 days (95% CI, 12.9-16.8 days). This time was increased by 15% (95% CI, -11 to 48%; P = 0.3) among infants who were exposed to antiretroviral therapy postnatally compared with infants who were not exposed. No effect was observed for mode of delivery. CONCLUSIONS: The outcome of an early virological test for HIV-1 is thought to be related directly to the timing of transmission and cesarean section delivery primarily reduces the risk of intrapartum transmission. The absence of an association between mode of delivery and viral detectability at birth was therefore unexpected. There was no evidence that foetal or neonatal exposure to prophylactic zidovudine delays substantially the diagnosis of infection, although this cannot be inferred for combination antiretroviral therapy.  相似文献   
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Previous studies suggest that quantifying donor‐reactive memory T cells prior to kidney transplantation by interferon gamma enzyme‐linked immunosorbent spot assay (IFNγELISPOT) can assist in assessing risk of posttransplant allograft injury. Herein, we report an analysis of IFNγELISPOT results from the multicenter, Clinical Trials in Organ Transplantation‐01 observational study of primary kidney transplant recipients treated with heterogeneous immunosuppression. Within the subset of 176 subjects with available IFNγELISPOT results, pretransplant IFNγELISPOT positivity surprisingly did not correlate with either the incidence of acute rejection (AR) or estimated glomerular filtration rate (eGFR) at 6‐ or 12‐month. These unanticipated results prompted us to examine potential effect modifiers, including the use of T cell‐depleting, rabbit anti‐thymocyte globulin (ATG). Within the no‐ATG subset, IFNγELISPOTneg subjects had higher 6‐ and 12‐month eGFRs than IFNγELISPOTpos subjects, independent of biopsy‐proven AR, peak PRA, human leukocyte antigen mismatches, African‐American race, donor source, and recipient age or gender. In contrast, IFNγELISPOT status did not correlate with posttransplant eGFR in subjects given ATG. Our data confirm an association between pretransplant IFNγELISPOT positivity and lower posttransplant eGFR, but only in patients who do not receive ATG induction. Controlled studies are needed to test the hypothesis that ATG induction is preferentially beneficial to transplant candidates with high frequencies of donor‐reactive memory T cells.  相似文献   
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