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71.
Background: In 2008, self-poisoning with the herbicide propanil had a case-fatality of around 11% in Sri Lanka. A simple quantitative methaemoglobinemia bedside test was developed so that treatment could be titrated according to the methaemoglobin level.

Objective: To determine whether the new method influenced patient management and changed the case fatality of propanil self-poisoning.

Method: The bedside test (using an inexpensive validated colour chart) was introduced in three hospitals (Anuradhapura, Polonnaruwa and Galle) in Sri Lanka from 2008. Junior ward staff were given a brief training on how to use the chart for quantitative estimation of methaemoglobin in patients with propanil poisoning and utilize the results in the context of the national treatment guidelines for propanil poisoning. It was taught that the bedside test should be done repeatedly from admission until it showed consistently low values of methaemoglobin. Treatment with the antidote methylene blue was suggested for patients whose methaemoglobin was greater than 20%. Limited clinical data on poisoning have been prospectively collected from these hospitals from 2003. The case-fatality and management before and after the change were compared with data up to December 2014.

Results: The case-fatality decreased from (38/401) 9.5% to (8/262) 3.1% [difference: ?6.4%, 95% CI: ?10 to ?3]. Methylene blue use increased from under 10% of patients before to 55% of patients after the intervention. More patients received repeat doses and infusions, and few received ascorbic acid and exchange transfusion.

Conclusion: The simple bedside test for methaemoglobinemia was readily adopted into routine practice and led to large changes in management. A substantial reduction in mortality from propanil poisoning occurred after this intervention.  相似文献   
72.
73.

Objectives

Highly active antiretroviral therapy (HAART) has dramatically changed the natural history of HIV infection in children, but there are few studies in the literature about the incidence of clinical manifestations after HAART in this population, compared with adults. The aim of this study was to describe the influence of the widespread use of HAART on the development of opportunistic infections and organ‐specific diseases in HIV‐infected children.

Methods

An observational study of a cohort of 366 vertically HIV‐infected children followed from 1990 to 2006 was carried out. According to the main antiretroviral protocol used, three calendar periods (CPs) were defined and compared: CP1 (1990–1996: no patients on HAART), CP2 (1997–1999: <60% on HAART) and CP3 (2000–2006: >60% on HAART).

Results

Children experienced a progressive increase in CD4 T cell count (P<0.05) and a decrease in HIV viral load from 1996 onwards (P<0.05). Similarly, rates of death, AIDS, opportunistic infections (bacteraemia, candidosis, cryptosporidiosis and bacterial pneumonia) and organ‐specific diseases (wasting syndrome, thrombocytopenia, cardiomyopathy, lymphoid interstitial pneumonia and HIV‐associated encephalopathy) were lower in CP2 and CP3 than in CP1.

Conclusions

This study provides evidence of improved clinical outcomes in HIV‐infected children over time and shows that mortality, AIDS, opportunistic infections and organ‐specific diseases declined as HAART was progressively instituted in this population.
  相似文献   
74.
75.
OBJECTIVE: To investigate eating disorder psychopathology, restraint and eating concern in young women with and without an eating disorder from two different ethnic groups in Australia and Singapore. METHOD: The relationship of Eating Disorder Examination Questionnaire Global, Restraint and Eating Concern scores to cultural orientation and sociocultural factors was analysed in 154 women with and without an eating disorder. Participants were from the following backgrounds: North European Australian, East Asian Australian, Singaporean Chinese and North European expatriates in Singapore. RESULTS: Women with eating disorders had similar psychopathology across the cultural groups. Among controls, Singaporean Chinese reported significantly greater overall eating disorder psychopathology than other cultural groups and greater restraint than North European Australians/expatriates. Eating concern was not associated with cultural group overall or acculturation to Western culture. Dissatisfaction with family functioning, socioeconomic status and education level were not significantly associated with any of the eating disorder measures. CONCLUSION: In eating disorder psychopathology, the specific symptom of eating concern may transcend cultural influences.  相似文献   
76.
It is known that anesthesia depresses neural activity and inhibits cortico-cortical interactions and cortical output. Hence, it is important to record from awake animals in order to better understand the full dynamic range of neural responses. We have developed a preparation for chronic, multi-electrode physiological recording in the cortex of the awake ferret. This paper discusses several of the advantages and disadvantages of the technique as well as procedures used to overcome potential complications associated with chronic implants in the ferret. Our solutions are well suited to the special species requirements, yet are also easily generalizable to other species.  相似文献   
77.

Background

In the setting of metastatic colorectal cancer (CRC), anti-EGFR antibodies are not currently recommended for individuals with KRAS mutant tumours. This is based on subgroup analyses of individual clinical trials rather than a formal synthesis of evidence for KRAS status as a predictive biomarker, while newer trials report no benefit for anti-EGFR antibodies irrespective of KRAS status. This study systematically reviewed the evidence for KRAS mutation status as a treatment effect modifier of response to anti-EGFR antibodies and the influence of partner chemotherapy.

Methods

Medline (1966-2010), EMBASE and American and European oncology meeting abstracts were searched for randomised controlled trials reporting the influence of KRAS status on effectiveness of anti-EGFR antibodies in metastatic CRC. The treatment efficacy was summarised by KRAS status using hazard ratios (HR) for progression-free survival (PFS) and risk differences (RD) for objective response. For each study, a measure of effect modification was calculated, and aggregated using random effects meta-analysis to assess the interaction between KRAS and treatment effect.

Findings

Eleven studies (8924 patients) were selected from 198 reports. Two studies assessed anti-EGFR antibodies as monotherapy and nine their use with chemotherapy. KRAS status was reported in 7555 cases. In subgroup analysis, the progression HR for KRAS wild patients assigned to anti-EGFR antibodies was 0.80 (4436 patients 95%CI: 0.64, 0.99) and for mutant cases 1.11 (3119 patients, 95%CI: 0.97, 1.27). A significant treatment effect interaction between KRAS status and addition of anti-EGFR antibodies to standard treatment was found for PFS (ratio of HRs 0.71, 95%CI: 0.57, 0.90 p = 0.005) and response rate difference (difference in RDs 15%, 95%CI: 8, 22%, p < 0.001). There was no evidence that the extent of effect modification differed between chemotherapeutic partners for both PFS (p = 0.3) and response rate (p = 0.6).

Interpretation

KRAS mutation status is a treatment effect modifier for anti-EGFR antibodies in metastatic CRC. Further evidence is needed to determine whether this is true for all chemotherapy partners and all clinical circumstances.  相似文献   
78.

Introduction

Australia has set the goal for the virtual elimination of HIV transmission by the end of 2022, yet accurate information is lacking on the level of HIV transmission occurring among residents. We developed a method for estimating the timing of HIV acquisition among migrants, relative to their arrival in Australia. We then applied this method to surveillance data from the Australian National HIV Registry with the aim of ascertaining the level of HIV transmission among migrants to Australia occurring before and after migration, and to inform appropriate local public health interventions.

Methods

We developed an algorithm incorporating CD4+ T-cell decline back-projection and enhanced variables (clinical presentation, past HIV testing history and clinician estimate of the place of HIV acquisition) and compared it to a standard algorithm which uses CD4+ T-cell back-projection only. We applied both algorithms to all new HIV diagnoses among migrants to estimate whether HIV infection occurred before or after arrival in Australia.

Results

Between 1 January 2016 and 31 December 2020, 1909 migrants were newly diagnosed with HIV in Australia, 85% were men, and the median age was 33 years. Using the enhanced algorithm, 932 (49%) were estimated to have acquired HIV after arrival in Australia, 629 (33%) before arrival (from overseas), 250 (13%) close to arrival and 98 (5%) were unable to be classified. Using the standard algorithm, 622 (33%) were estimated to have acquired HIV in Australia, 472 (25%) before arrival, 321 (17%) close to arrival and 494 (26%) were unable to be classified.

Conclusions

Using our algorithm, close to half of migrants diagnosed with HIV were estimated to have acquired HIV after arrival in Australia, highlighting the need for tailored culturally appropriate testing and prevention programmes to limit HIV transmission and achieve elimination targets. Our method reduced the proportion of HIV cases unable to be classified and can be adopted in other countries with similar HIV surveillance protocols, to inform epidemiology and elimination efforts.  相似文献   
79.
80.
Hahn  PF; Stark  DD; Vici  LG; Ferrucci  JT  Jr 《Radiology》1986,159(2):379-382
Proper management of duodenal hematoma requires that an accurate diagnosis be made using noninvasive radiological methods. Conventional imaging may be nonspecific if there is no history of trauma or coagulopathy. Two cases of duodenal hematoma that were imaged by magnetic resonance (MR) and computed tomography (CT) are described. In both cases the hematoma had a well-defined concentric ring configuration on MR images, a finding which helped establish the diagnosis. MR imaging may provide tissue-specific characterization of duodenal hematomas.  相似文献   
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