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1.
Long-term monitoring began 20 years ago at Burnham Beeches Site of Special Interest (SSSI), National Nature Reserve (NNR) and European Special Area of Conservation (SAC) lying 40 km west of London as a consequence of the authorization of an application to extract gravel from an adjacent site lying north of Slough Trading Estate. Dust monitoring (sticky pads) and photographic monitoring, recording and image analysis was instigated in 1992 on Parmelion communities to assess changes in lichen growth, health and community composition. Long-term monitoring identifies that the lichen flora on free-standing trees has undergone rapid expansion from a near dominance by the SO2-tolerant ‘acidophyte’ species Lecanora conizaeoides and Hypogymnia physodes following reductions in SO2 concentrations. Long-term influences of low levels of eutrophication, gaseous pollutants (particularly globally rising background ozone concentrations) on lichen and bryophyte communities and succession under changing climatic conditions are unknown. Soil–plant relationships, lichen–invertebrate interactions and a pollution legacy must also be considered.  相似文献   
2.
Twelve groups of fossils, including graptolites, brachiopods, nautiloids, trilobites, corals, crinoids, bryozoans, conodonts, ostracods, gastropods, chitinozoans, and acritarchs expired in different but substantial magnitude and global extent during the late Caradoc to latest Ashgill. It indicates a multiple‐episodic mass extinction containing the possible Prologue (late Caradoc), Climax episode (Rawtheyan) and Epilogue (late Hirnantian). The main causes of this mass extinction are recognized as a global sea‐level lowering in the climax and remarkable rapid rise at the final, and global cooling. The Chinese data, especially from the South China Paleoplate, are evaluated first. They are significant for explaining this global bioevent.  相似文献   
3.
This paper discusses regression analysis of longitudinal data in which the observation process may be related to the longitudinal process of interest. Such data have recently attracted a great deal of attention and some methods have been developed. However, most of those methods treat the observation process as a recurrent event process, which assumes that one observation can immediately follow another. Sometimes, this is not the case, as there may be some delay or observation duration. Such a process is often referred to as a recurrent episode process. One example is the medical cost related to hospitalization, where each hospitalization serves as a single observation. For the problem, we present a joint analysis approach for regression analysis of both longitudinal and observation processes and a simulation study is conducted that assesses the finite sample performance of the approach. The asymptotic properties of the proposed estimates are also given and the method is applied to the medical cost data that motivated this study.  相似文献   
4.
To investigate the relationship between oxidative stress and progressive spread of the stroke-like lesions in mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) with 3243A>G mutation, we retrospectively analyzed the spread frequency in patients with and without treatment with the radical scavenger edaravone. Oxidative damage and defensive enzymes were histologically evaluated. Spread was significantly less frequent in the patients treated with edaravone. Although 8-hydroxy-2′-deoxyguanosine, a marker for oxidative damage of DNA, was obviously accumulated in peri-lesional surviving neurons, manganese superoxide dismutase and 8-oxoguanine glycosylase 1 were not up-regulated in those neurons. Increased oxidative stress and insufficient defense could be involved in the pathogenesis of the spreading lesions in MELAS.  相似文献   
5.
BackgroundElectronic health records are frequently used for cancer epidemiology. We report on their quality for ascertaining colorectal cancer (CRC) in UK women.MethodsPopulation-based, retrospective cohort study nested within the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS). Postmenopausal women aged 50–74 who were diagnosed with CRC during 2001–11 following randomisation to the UKCTOCS were identified and their diagnosis confirmed with their treating clinician. The sensitivity and positive predictive value (PPV) of cancer and death registries, hospital episode statistics, and self-reporting were calculated by pairwise comparisons to the treating clinician’s confirmation, while specificity and negative predictive value were estimated relative to expected cases.ResultsNotification of CRC events were received for 1,085 women as of 24 May 2011. Responses were received from 61% (660/1,085) of clinicians contacted. Nineteen women were excluded (18 no diagnosis date, one diagnosed after cut-off). Of the 641 eligible, 514 had CRC, 24 had a benign polyp, and 103 had neither diagnosis. The sensitivity of cancer registrations at one- and six-years post-diagnosis was 92 (95% CI 90–94) and 99% (97–100), respectively, with a PPV of 95% (95% CI 92/93–97). The sensitivity & PPV of cancer registrations (at one-year post-diagnosis) & hospital episode statistics combined were 98 (96–99) and 92% (89–94), respectively.ConclusionsCancer and death registrations in the UK are a reliable resource for CRC ascertainment in women. Hospital episode statistics can supplement delays in cancer registration. Self-reporting seems less reliable.  相似文献   
6.
Spontaneous coronary artery dissection (SCAD) is a very rare cause of acute coronary syndromes in young otherwise healthy patients with a striking predilection for the female gender. The pathological mechanism has not been fully clarified yet. However, several diseases and conditions have been associated with SCAD, such as atherosclerosis, connective tissue disorders and the peripartum episode. In this paper we present a review of the literature, discussing the possible mechanisms for SCAD, therapeutic options and prognosis. The review is illustrated with two SCAD patients who had a recurrence of a spontaneous dissection in another artery within a few days after the initial event. Because of the susceptibility to recurrent spontaneous dissections we propose at least one week of observation in hospital. Further, we will elaborate on the possible conservative and invasive treatment strategies in the acute phase of SCAD. Primary percutaneous coronary intervention remains the reperfusion strategy of choice; however, in small and medium-sized arteries with normalised flow conservative treatment is defendable. In addition, after the acute phase evaluation of possible underlying diseases is necessary, because it affects further treatment. (Neth Heart J 2008;16:344-9.)  相似文献   
7.
Outcomes of psychotic disorders are associated with high personal, familiar, societal and clinical burden. There is thus an urgent clinical and societal need for improving those outcomes. Recent advances in research knowledge have opened new opportunities for ameliorating outcomes of psychosis during its early clinical stages. This paper critically reviews these opportunities, summarizing the state‐of‐the‐art knowledge and focusing on recent discoveries and future avenues for first episode research and clinical interventions. Candidate targets for primary universal prevention of psychosis at the population level are discussed. Potentials offered by primary selective prevention in asymptomatic subgroups (stage 0) are presented. Achievements of primary selected prevention in individuals at clinical high risk for psychosis (stage 1) are summarized, along with challenges and limitations of its implementation in clinical practice. Early intervention and secondary prevention strategies at the time of a first episode of psychosis (stage 2) are critically discussed, with a particular focus on minimizing the duration of untreated psychosis, improving treatment response, increasing patients’ satisfaction with treatment, reducing illicit substance abuse and preventing relapses. Early intervention and tertiary prevention strategies at the time of an incomplete recovery (stage 3) are further discussed, in particular with respect to addressing treatment resistance, improving well‐being and social skills with reduction of burden on the family, treatment of comorbid substance use, and prevention of multiple relapses and disease progression. In conclusion, to improve outcomes of a complex, heterogeneous syndrome such as psychosis, it is necessary to globally adopt complex models integrating a clinical staging framework and coordinated specialty care programmes that offer pre‐emptive interventions to high‐risk groups identified across the early stages of the disorder. Only a systematic implementation of these models of care in the national health care systems will render these strategies accessible to the 23 million people worldwide suffering from the most severe psychiatric disorders.  相似文献   
8.
肺炎支原体感染与小儿支气管哮喘急性发作的关系   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:研究肺炎支原体(MP)感染与支气管哮喘急性发作的相关性。方法:选择我院2012年10月~2013年9月收治的支气管哮喘急性发作和缓解期患儿,作为观察组和对照组,分析两组患儿血清中MP特异性IgM(MP-IgM)和咽拭子MP-DNA的检测结果。结果:观察组MP-IgM和MP-DNA阳性率以及MP-DNA拷贝量均显著高于对照组(P0.05)。结论:MP感染与小儿支气管哮喘急性发作具有密切关系,MP-IgM和MP-DNA检测,可为临床诊疗提供一定的参考依据。  相似文献   
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ABSTRACT

At the Center for Addiction and Mental Health (CAMH) Integrated Day Treatment (IDT) program, each patient attends either a morning stream or an afternoon stream, but not both. We examined whether subjective chronotype, or the time of day an individual prefers to be most active and alert, predicted treatment outcomes differentially in depressed patients attending the morning vs. afternoon IDT streams. The Horne-Östberg Morningness-Eveningness Questionnaire (MEQ) was administered before IDT treatment to 203 consecutive patients experiencing a major depressive episode. Multiple regression was used to predict change in depression and quality of life scores based on treatment stream (morning or afternoon), baseline MEQ scores and the treatment stream by MEQ interaction. The treatment stream by MEQ interaction was a highly significant predictor of both depression and quality of life change scores. Post-hoc analyses based on established MEQ categories revealed that definite evening chronotypes had significantly better responses in the morning stream than did morning chronotypes, and significantly worse responses in the afternoon stream relative to moderate evening or neutral chronotypes. There were insufficient morning chronotypes in the afternoon stream to assess clinical responses for this subgroup. In the morning stream only, there was a significant positive correlation between the change in MEQ scores after four weeks of IDT treatment (i.e. a shift to greater morningness) and the decrease in depression scores (r = .36, p = .003), consistent with a therapeutic phase advance in circadian rhythms. In sum, these preliminary data suggest that definite evening chronotypes may have the greatest relative benefit from attending the morning vs. afternoon IDT stream. As patients currently select which IDT stream they will attend, future work based on randomized treatment assignment and using passive actigraphy to assess circadian phase is currently planned to extend these preliminary findings.  相似文献   
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