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排序方式: 共有405条查询结果,搜索用时 15 毫秒
101.
Haddow LJ Colebunders R Meintjes G Lawn SD Elliott JH Manabe YC Bohjanen PR Sungkanuparph S Easterbrook PJ French MA Boulware DR;International Network for the Study of HIV-associated IRIS 《The Lancet infectious diseases》2010,10(11):791-802
Cryptococcal immune reconstitution inflammatory syndrome (IRIS) may present as a clinical worsening or new presentation of cryptococcal disease after initiation of antiretroviral therapy (ART), and is thought to be caused by recovery of cryptococcus-specific immune responses. We have reviewed reports of cryptococcal IRIS and have developed a consensus case definition specifically for paradoxical crytopcoccal IRIS in patients with HIV-1 and known cryptococcal disease before ART, and a separate definition for incident cryptococcosis developed during ART (termed ART-associated cryptococcosis), for which a proportion of cases are likely to be unmasking cryptococcal IRIS. These structured case definitions are intended to aid design of future clinical, epidemiological, and immunopathological studies of cryptococcal IRIS, to standardise diagnostic criteria, and to facilitate comparisons between studies. As for definitions of tuberculosis-associated IRIS, definitions for cryptococcal IRIS should be regarded as preliminary until further insights into the immunopathology of IRIS permit their refinement. 相似文献
102.
103.
Ben J Marais Knut Lönnroth Stephen D Lawn Giovanni Battista Migliori Peter Mwaba Philippe Glaziou Matthew Bates Ruth Colagiuri Lynn Zijenah Soumya Swaminathan Ziad A Memish Michel Pletschette Michael Hoelscher Ibrahim Abubakar Rumina Hasan Afia Zafar Guiseppe Pantaleo Gill Craig Alimuddin Zumla 《The Lancet infectious diseases》2013,13(5):436-448
104.
We compared clinical features and prognosis of 72 adults with a first-ever seizure presentation comprising multiple discrete seizures within 24 hours to 425 patients presenting with a single seizure. Those presenting with multiple seizures were no more likely to have seizure recurrence, irrespective of etiology or treatment. Hence, a presentation with multiple seizures within 24 hours should be regarded as a single event, in keeping with the International League Against Epilepsy recommendations. 相似文献
105.
OBJECTIVE: To determine the burden and impact of immune reconstitution disease (IRD) associated with tuberculosis (TB) among patients initiating antiretroviral treatment (ART) in sub-Saharan Africa. DESIGN: Retrospective analysis of a study cohort enrolled over 3 years within a community-based ART service in South Africa. METHODS: Patients receiving treatment for TB at the time ART was initiated (n = 160) were studied. Cases of TB-associated IRD during the first 4 months of ART were ascertained. RESULTS: The median baseline CD4 cell count was 68 cells/microl [interquartile range (IQR), 29-133 cells/microl) and ART was initiated after a median of 105 days (IQR, 61-164 days) from TB diagnosis. Although IRD was diagnosed in just 12% (n = 19) of patients overall, IRD developed in 32% (n = 12) of those who started ART within 2 months of TB diagnosis. Pulmonary involvement was observed in 84% (n = 16) and intra-abdominal manifestations were also common (37%). Overall, 4% (n = 7) of the cohort required secondary level health-care for IRD and two (1%) patients died. In multivariate analysis, risk of IRD was strongly associated with early ART initiation and low baseline CD4 cell count. Of patients with CD4 counts < 50 cells/microl, the proportions who developed IRD following initiation of ART within 0-30, 31-60, 61-90, 91-120 and > 120 days of TB diagnosis were 100%, 33%, 14%, 7% and 0%, respectively. CONCLUSIONS: The risk of TB-associated IRD in this setting is very high for those with low baseline CD4 cell counts initiating ART early in the course of antituberculosis treatment. However, most cases were self-limiting; overall secondary health-care utilization and mortality risk from IRD were low. 相似文献
106.
107.
Wood R Middelkoop K Myer L Grant AD Whitelaw A Lawn SD Kaplan G Huebner R McIntyre J Bekker LG 《American journal of respiratory and critical care medicine》2007,175(1):87-93
BACKGROUND: Although failure of tuberculosis (TB) control in sub-Saharan Africa is attributed to the HIV epidemic, it is unclear why the directly observed therapy short-course (DOTS) strategy is insufficient in this setting. We conducted a cross-sectional survey of pulmonary TB (PTB) and HIV infection in a community of 13,000 with high HIV prevalence and high TB notification rate and a well-functioning DOTS TB control program. METHODS: Active case finding for PTB was performed in 762 adults using sputum microscopy and Mycobacterium tuberculosis culture, testing for HIV, and a symptom and risk factor questionnaire. Survey findings were correlated with notification data extracted from the TB treatment register. RESULTS: Of those surveyed, 174 (23%) tested HIV positive, 11 (7 HIV positive) were receiving TB therapy, 6 (5 HIV positive) had previously undiagnosed smear-positive PTB, and 6 (4 HIV positive) had smear-negative/culture-positive PTB. Symptoms were not a useful screen for PTB. Among HIV-positive and -negative individuals, prevalence of notified smear-positive PTB was 1,563/100,000 and 352/100,000, undiagnosed smear-positive PTB prevalence was 2,837/100,000 and 175/100,000, and case-finding proportions were 37 and 67%, respectively. Estimated duration of infectiousness was similar for HIV-positive and HIV-negative individuals. However, 87% of total person-years of undiagnosed smear-positive TB in the community were among HIV-infected individuals. CONCLUSIONS: PTB was identified in 9% of HIV-infected individuals, with 5% being previously undiagnosed. Lack of symptoms suggestive of PTB may contribute to low case-finding rates. DOTS strategy based on passive case finding should be supplemented by active case finding targeting HIV-infected individuals. 相似文献
108.
109.
Joy E Lawn Mohammad Yawar Yakoob Rachel A Haws Tanya Soomro Gary L Darmstadt Zulfiqar A Bhutta 《BMC pregnancy and childbirth》2009,9(Z1):S2
More than 3.2 million stillbirths occur globally each year, yet stillbirths are largely invisible in global data tracking, policy dialogue and programme implementation. This mismatch of burden to action is due to a number of factors that keep stillbirths hidden, notably a lack of data and a lack of consensus on priority interventions, but also to social taboos that reduce the visibility of stillbirths and the associated family mourning. Whilst there are estimates of the numbers of stillbirths, to date there has been no systematic global analysis of the causes of stillbirths. The multiple classifications systems in use are often complex and are primarily focused on high-income countries. We review available data and propose a programmatic classification that is feasible and comparable across settings. We undertook a comprehensive global review of available information on stillbirths in order to 1) identify studies that evaluated risk factors and interventions to reduce stillbirths, 2) evaluate the level of evidence for interventions, 3) place the available evidence for interventions in a health systems context to guide programme implementation, and 4) elucidate key implementation, monitoring, and research gaps. This first paper in the series outlines issues in stillbirth data availability and quality, the global epidemiology of stillbirths, and describes the methodology and framework used for the review of interventions and strategies. 相似文献
110.
Use of contact testing in the characterization and design of all-ceramic crownlike layer structures: a review. 总被引:4,自引:0,他引:4
Ceramic-based crowns, particularly molar crowns, can fail prematurely from accumulation of fracture and other damage in continual occlusal contact. Damage modes depend on ceramic types (especially microstructures), flaw states, loading conditions, and geometric factors. These damage modes can be simulated and characterized in the laboratory with the use of Hertzian contact testing on monolayer, bilayer, and trilayer structures to represent important aspects of crown response in oral function. This article reviews the current dental materials knowledge base of clinically relevant contact-induced damage in ceramic-based layer structures in the context of all-ceramic crown lifetimes. It is proposed that simple contact testing protocols that make use of sphere indenters on model flat, ceramic-based layer structures-ceramic/polymer bilayers (simulating monolithic ceramic crowns on dentin) and ceramic/ceramic/polymer trilayers (simulating veneer/core all-ceramic crowns on dentin)-can provide useful relations for predicting critical occlusal loads to induce lifetime-threatening fracture. It is demonstrated that radial cracking from the lower core layer surface is the dominant failure mode for ceramic layer thicknesses much below 1 mm. Such an approach may be used to establish a scientific, materials-based foundation for designing next-generation crown layer structures. 相似文献