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111.
Sharifah B. Alhadad Ivan C.C. Low Jason K.W. Lee 《Journal of Science and Medicine in Sport》2021,24(1):105-109
ObjectivesWe investigated the thermoregulatory responses to ice slurry ingestion during low- and moderate-intensity exercises with restrictive heat loss.DesignRandomised, counterbalanced, cross-over design.MethodsFollowing a familiarisation trial, ten physically active males exercised on a motorised treadmill at low-intensity (L; 40% VO2max) or moderate-intensity (M; 70% VO2max) for 75-min, in four randomised, counterbalanced trials. Throughout the exercise bout, participants donned a raincoat to restrict heat loss. Participants ingested 2 g kg?1 body mass of ambient water (L + AMB and M + AMB trials) or ice slurry (L + ICE and M + ICE trials) at 15-min intervals during exercise in environmental conditions of Tdb, 25.1 ± 0.6 °C and RH, 63 ± 5%. Heart rate (HR), gastrointestinal temperature (Tgi), mean weighted skin temperature (Tsk), estimated sweat loss, ratings of perceived exertion (RPE) and thermal sensation (RTS) were recorded.ResultsCompared to L + AMB, participants completed L + ICE trials with lower ΔTgi (0.8 ± 0.3°C vs 0.6 ± 0.2 °C; p = 0.03), mean RPE (10 ± 1 vs 9 ± 1; p = 0.03) and estimated sweat loss (0.91 ± 0.2 L vs 0.78 ± 0.27 L; p = 0.04). Contrastingly, Tgi (p = 0.22), Tsk (p = 0.37), HR (p = 0.31), RPE (p = 0.38) and sweat loss (p = 0.17) were similar between M + AMB and M + ICE trials. RTS was similar during both low-intensity (4.9 ± 0.5 vs 4.7 ± 0.3; p = 0.10) and moderate-intensity exercise (5.3 ± 0.47 vs 5.0 ± 0.4; p = 0.09).ConclusionsPer-cooling using ice slurry ingestion marginally reduced thermal strain during low-intensity but not during moderate-intensity exercise. Ice slurry may be an effective and practical heat mitigation strategy during low-intensity exercise such as in occupational and military settings, but a greater volume should be considered to ensure its efficacy. 相似文献
112.
Kathryn Graff Low Hannah Giasson Stephanie Connors Deborah Freeman Robert Weiss 《International journal of behavioral medicine》2013,20(1):77-81
Background
Obesity has reached epidemic proportions in the USA and is a particular threat to those with coronary disease. Motivational interviewing (MI) is a client-centered, directive method for enhancing intrinsic motivation to change by exploring and resolving ambivalence about altering behavior.Purpose
This study examined the efficacy of MI compared to nutritional counseling for weight loss in a small sample of obese cardiac patients.Method
Participants were assigned to either MI or to nutrition counseling and followed up over 3 months. Trained undergraduate students delivered the MI intervention.Results
There were significant reductions in weight in women in the MI intervention, but not in men.Conclusion
The results suggest that MI may be effective for obese female cardiac patients, in particular, even when delivered by nonprofessional interviewers. Limitations of the study include a small sample size, nonrandomized assignment to conditions, and attrition over time. 相似文献113.
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Objective:
To evaluate current UK practice of periprocedural haematological management for image-guided procedures in relation to Cardiovascular and Interventional Radiological Society guidelines, which provide recommendations according to bleeding risk of procedures from Category 1 (lowest) to 3 (highest).Methods:
Survey of practice in UK radiology departments conducted over a 1-year periodResults:
48 radiology departments responded. The percentage of departments that stop antithrombotics pre-procedurally are as follows (for Category 1, 2 and 3, respectively): aspirin (31.3%, 43.8%, 54.2%); clopidogrel (54.2%, 68.8%, 72.9%); therapeutic low-molecular-weight heparin (56.3%, 77.1%, 75.0%). The percentage of departments that perform pre-procedural laboratory testing are as follows (for Category 1, 2 and 3, respectively): international normalized ratio (INR; 81.3%, 95.8%, 93.8%); activated partial thrombin time ratio (APTTR; 60.4%, 75.0%, 93.8%); platelet (77.1%, 91.7%, 95.7%); haemoglobin (70.8%, 85.4%, 87.5%). Mean threshold (standard deviation) of laboratory results for conducting procedures (Level 1, 2 and 3, respectively) are as follows: INR [1.53 (0.197), 1.47 (0.186), 1.47 (0.188)]; APTTR [1.50 (0.392), 1.50 (0.339), 1.48 (0.344)]; platelet count (x103 cells per microlitre) [74.4 (28.7), 79.9 (29.1), 80.5 (29.3)]; haemoglobin (grams per decilitre) [9.05 (1.40), 9.00 (1.33), 8.92 (1.21)]. No department practices conformed to current recommendations for (1) pre-procedural cessation of antithrombotics and (2) pre-procedural laboratory testing. Two (4.2%) department practices conformed to recommendations for thresholds of haematological parameters.Conclusion:
Current peri-procedural haematological management is variable and often does not conform to existing recommendations. Further research into the impact of this variation in practice on patient outcome is requiredAdvances in Knowledge:
This study demonstrates wide variation in practice in haematological management for image-guided procedures.Periprocedural haematological management, such as correction of coagulopathy, cessation of antithrombotics and pre-procedural laboratory testing (e.g. for haemoglobin levels and platelet count), is an important consideration for patients undergoing image-guided procedures.1 The challenges of periprocedural haematological management are multifactorial in aetiology. In addition to the increasing range of complex image-guided procedures being performed, the patient population undergoing such procedures may also be complicated.2 Many of these patients have comorbidities requiring antithrombotic therapy, or may have liver and marrow dysfunction, which can affect bleeding risk. Decisions on the optimal periprocedural haematological management are also confounded by the lack of high-level evidence, and existing guidelines within the literature can be variable even for equivalent procedures. For example, in two separate internationally accepted guidelines, the recommended international normalized ratio (INR) for chest drain insertion is <1.5 and <2.0.3,4 There is also limited scope to transfer existing evidence on haematological management from other domains such as open surgery to image-guided interventions. Unlike conventional open surgical procedures where bleeding may be visualized immediately and controlled by direct pressure or vessel ligation, bleeding from image-guided procedures may be difficult to control owing to issues with access and identification.5The lack of high-level evidence is unsurprising, given the potential ethical issues in conducting the necessary studies; it would be difficult to justify the randomization of patients to receiving or not receiving coagulopathy correction prior to undergoing various image-guided procedures for the purpose of research.6 As a result, current evidence is often based on retrospective studies. To address this complex issue, the Society of Interventional Radiology in conjunction with the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) has previously produced guidelines based on existing evidence and expert consensus on periprocedural haematological management for image-guided procedures which are stratified into three categories according to the bleeding risk (4 However, despite the existence of such guidelines, from our experience, significant variation in practice exists between clinicians, even within our own institution.Table 1.
Society of Interventional Radiology/Cardiovascular and Interventional Radiological Society of Europe consensus guidelines on periprocedural haematological management for image-guided procedures according to category of bleeding riskGuideline item | Guidance according to category of bleeding risk | |||
---|---|---|---|---|
Category 1 (low risk) | Category 2 (intermediate risk) | Category 3 (high risk) | ||
Examples of procedures | ||||
Vascular | Venography, IVC filter, PICC line | Arterial intervention (access size up to 7 French), chemoembolization, uterine fibroid embolization | TIPS | |
Non-vascular | Thoracentesis, paracentesis, superficial aspiration and biopsy | Intra-abdominal abscess drainage, lung biopsy, percutaneous cholecystostomy | Renal biopsy, biliary interventions (new tract), nephrostomy | |
Antiplatelet/anticoagulation cessation | ||||
Aspirin | Do not withhold | Do not withhold | Withhold 5-day pre-procedure | |
Clopidogrel | Do not withhold | Withhold 5-day pre-procedure | Withhold 5-day pre-procedure | |
Therapeutic LMWH | Withhold one-dose pre-procedure | Withhold one-dose pre-procedure | Withhold for 24 h/up to two doses | |
Pre-procedural testing | ||||
INR | On warfarin/with liver disease | All patients | All patients | |
APTTR | On unfractionated heparin | On unfractionated heparin | On unfractionated heparin | |
Platelet count | Not routinely recommended | Not routinely recommended | All patients | |
Haemoglobin | Not routinely recommended | Not routinely recommended | All patients | |
Threshold for correcting parameter/withholding procedure | ||||
INR | INR >2.0 | >1.5 (89% consensus) | >1.5 (95% consensus) | |
APTTR | No consensus | No consensus | >1.5 times control | |
Platelet count | Transfusion if <50 × 103 μl−1 | Transfusion if <50 × 103 μl−1 | Transfusion if <50 × 103 μl−1 | |
Haemoglobin | No recommended threshold | No recommended threshold | No recommended threshold |
116.
Conservation of the primosome in successive stages of phi X174 DNA replication. 总被引:2,自引:8,他引:2
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R L Low K Arai A Kornberg 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(3):1436-1440
Synthesis of a complementary strand to match the single-stranded, circular, viral (+) DNA strand of phage phi X174 creates a parental duplex circle (replicative form, RF). This synthesis is initiated by the assembly and action of a priming system, called the primosome [Arai, K. & Kornberg, A (1981) Proc. Natl. Acad. Sci. USA 78, 69-73; Arai, K., Low, R. L. & Kornberg, A. (1981) Proc. Natl. Acad. Sci. USA 78, 707-711]. Of the seven proteins that participate in the assembly and function of the primosome, most all of the components remain even after the DNA duplex is completed and covalently sealed. Remarkably, the primosome in the isolated RF obviates the need for supercoiling of RF by DNA gyrase, an action previously considered essential for the site-specific cleavage by gene A protein that starts viral strand synthesis in the second stage of phi X174 DNA replication. Finally, priming of the synthesis of complementary strands on the nascent viral strands to produce many copies of progeny RF utilizes the same primosome, requiring the addition only of prepriming protein i. thus a single primosome, which becomes associated with the incoming viral DNA in the initial stage of replication, may function repeatedly in the initiation of complementary strands at the subsequent stage of RF multiplication. These patterns of phi X174 DNA replication suggest that a conserved primosome also functions in the progress of the replicating fork of the Escherichia coli chromosome, particularly in initiating the synthesis of nascent (Okazaki) fragments. 相似文献
117.
118.
Sean Molloy Maggie Lai Guy Pratt Karthik Ramasamy David Wilson Nasir Quraishi Martin Auger David Cumming Maqsood Punekar Michael Quinn Debo Ademonkun Fenella Willis Jane Tighe Gordon Cook Alistair Stirling Timothy Bishop Cathy Williams Bronek Boszczyk Jeremy Reynolds Mel Grainger Niall Craig Alastair Hamilton Isobel Chalmers Sam Ahmedzai Susanne Selvadurai Eric Low Charalampia Kyriakou the UK Spinal Myeloma Working Group 《British journal of haematology》2015,171(3):332-343
Myeloma is one of the most common malignancies that results in osteolytic lesions of the spine. Complications, including pathological fractures of the vertebrae and spinal cord compression, may cause severe pain, deformity and neurological sequelae. They may also have significant consequences for quality of life and prognosis for patients. For patients with known or newly diagnosed myeloma presenting with persistent back or radicular pain/weakness, early diagnosis of spinal myeloma disease is therefore essential to treat and prevent further deterioration. Magnetic resonance imaging is the initial imaging modality of choice for the evaluation of spinal disease. Treatment of the underlying malignancy with systemic chemotherapy together with supportive bisphosphonate treatment reduces further vertebral damage. Additional interventions such as cement augmentation, radiotherapy, or surgery are often necessary to prevent, treat and control spinal complications. However, optimal management is dependent on the individual nature of the spinal involvement and requires careful assessment and appropriate intervention throughout. This article reviews the treatment and management options for spinal myeloma disease and highlights the value of defined pathways to enable the proper management of patients affected by it. 相似文献
119.
Rameysh Danovani Mahmood Zhi Yong Chen Teck Boon Low Keng Sin Ng 《Singapore medical journal》2015,56(3):e42-e45
Bronchial artery aneurysm is uncommon, and the occurrence of multiple aneurysms arising from a bronchial artery is even rarer. To date, there has been only one published case report describing double bronchial artery aneurysms. We herein describe a case of three aneurysms arising from a left bronchial artery, accompanied by multiple bilateral hypertrophied bronchial and intercostobronchial arteries, as well as a double aortic arch. Bronchial artery aneurysm is potentially life-threatening, and immediate treatment is recommended to minimise the potential risk of rupture. The aneurysms in our case were successfully treated via transcatheter arterial embolisation using coils. 相似文献
120.