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51.
52.

Background

Intravenous recombinant tissue plasminogen activator (rt-PA) is approved for use in selected patients with ischaemic stroke within 3 hours of symptom onset. IST-3 seeks to determine whether a wider range of patients may benefit.

Design

International, multi-centre, prospective, randomized, open, blinded endpoint (PROBE) trial of intravenous rt-PA in acute ischaemic stroke. Suitable patients must be assessed and able to start treatment within 6 hours of developing symptoms, and brain imaging must have excluded intracerebral haemorrhage. With 1000 patients, the trial can detect a 7% absolute difference in the primary outcome. With3500 patients, it can detect a 4.0% absolute benefit & with 6000, (mostly treated between 3 & 6 hours), it can detect a 3% benefit.

Trial procedures

Patients are entered into the trial by telephoning a fast, secure computerised central randomisation system or via a secure web interface. Repeat brain imaging must be performed at 24–48 hours. The scans are reviewed 'blind' by expert readers. The primary measure of outcome is the proportion of patients alive and independent (Modified Rankin 0–2) at six months (assessed via a postal questionnaire mailed directly to the patient). Secondary outcomes include: events within 7 days (death, recurrent stroke, symptomatic intracranial haemorrhage), outcome at six months (death, functional status, EuroQol).

Trial registration

ISRCTN25765518  相似文献   
53.

Background  

Chronic obstructive pulmonary disease (COPD) is characterized by a chronic inflammatory process, in which the pro-inflammatory cytokine Tumor Necrosis Factor (TNF)-α is considered to play a role. In the present study the putative involvement of TNF-α gene polymorphisms in pathogenesis of COPD was studied by analysis of four TNF-α gene polymorphisms in a Caucasian COPD population.  相似文献   
54.
We developed a new and simple method to collect sections of a whole brown rice kernel for investigation of histological properties. A single kernel of rice was dehydrated through a graded ethanol series, transferred to xylene, and embedded in paraffin. During sectioning of the blocks using a rotary microtome, we used a special adhesive tape to collect and place the sections on slides so they remained flat. The use of the adhesive tape technique combined with autofluorescence characteristics allowed us to visualize cell walls throughout an entire longitudinal or transverse section of a whole rice kernel. We obtained scanning electron microscopy images of the sections to determine section quality.  相似文献   
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Phylogenetic reconstruction of vertebrate Hox cluster duplications   总被引:8,自引:2,他引:6  
In vertebrates and the cephalochordate, amphioxus, the closest vertebrate relative, Hox genes are linked in a single cluster. Accompanying the emergence of higher vertebrates, the Hox gene cluster duplicated in either a single step or multiple steps, resulting in the four-cluster state present in teleosts and tetrapods. Mammalian Hox clusters (designated A, B, C, and D) extend over 100 kb and are located on four different chromosomes. Reconstructing the history of the duplications and its relation to vertebrate evolution has been problematic due to the lack of alignable sequence information. In this study, the problem was approached by conducting a statistical analysis of sequences from the fibrillar-type collagens (I, II, III, and IV), genes closely linked to each Hox cluster which likely share the same duplication history as the Hox genes. We find statistical support for the hypothesis that the cluster duplication occurred as multiple distinct events and that the four-cluster situation arose by a three- step sequential process.   相似文献   
59.
Drebrin is a cytoskeleton‐associated protein which can interact with both actin filaments and the tips of microtubules. Its roles have been studied mostly in dendrites, and the functions of drebrin in axons are less well understood. In this study, we analyzed the role of drebrin, through shRNA‐mediated depletion and overexpression, in the collateral branching of chicken embryonic sensory axons. We report that drebrin promotes the formation of axonal filopodia and collateral branches in vivo and in vitro. Live imaging of cytoskeletal dynamics revealed that drebrin promotes the formation of filopodia from precursor structures termed axonal actin patches. Endogenous drebrin localizes to actin patches and depletion studies indicate that drebrin contributes to the development of patches. In filopodia, endogenous drebrin localizes to the proximal portion of the filopodium. Drebrin was found to promote the stability of axonal filopodia and the entry of microtubule plus tips into axonal filopodia. The effects of drebrin on the stabilization of filopodia are independent of its effects on promoting microtubule targeting to filopodia. Inhibition of myosin II induces a redistribution of endogenous drebrin distally into filopodia, and further increases branching in drebrin overexpressing neurons. Finally, a 30 min treatment with the branch‐inducing signal nerve growth factor increases the levels of axonal drebrin. This study determines the specific roles of drebrin in the regulation of the axonal cytoskeleton, and provides evidence that drebrin contributes to the coordination of the actin and microtubule cytoskeleton during the initial stages of axon branching. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1092–1110, 2016  相似文献   
60.
The Olifants River, a tributary of the Limpopo River system, is one of the most polluted rivers in South Africa. In May 2011 the concentrations of metals in fish muscle tissue from two impoundments, Loskop and Flag Boshielo dams, on the Olifants River were measured and a human health risk assessment conducted to investigate whether it was safe to consume Labeo rosae from these impoundments. Labeo rosae is one of the most common pan fish in these impoundments and is readily available to rural communities. Metals are accumulating in the muscle tissue of L. rosae even although the fish populations appear to be healthy. At Loskop Dam all L. rosae analysed exceeded the recommended hazard quotient (HQ) of 1 for antimony, and less than 50% exceeded that for lead. At Flag Boshielo Dam, the recommended HQ was exceeded for lead in less than 50% of L. rosae analysed, and more than 50% exceeded that for antimony. The weekly consumption of 150?g of L. rosae muscle tissue from these impoundments may pose an unacceptable health risk to rural communities.  相似文献   
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