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排序方式: 共有8918条查询结果,搜索用时 15 毫秒
101.
A recent development in antithrombotic research allows the inhibition of platelet aggregation via protection of the glycoprotein IIb/IIIa receptor on the platelet membrane. We hypothesized that a GP IIb/IIIa receptor inhibitor would inhibit thromboxane-induced platelet aggregation during circulation in our in vitro ventricular assist device (VAD) circuit and preserve long-term platelet function. Twenty-one in vitro nonpulsatile centrifugal VAD circuits were simulated for 4 days using 450 ml of fresh human whole blood with or without glycoprotein IIb/IIIa receptor inhibitor (tirofiban). Platelet aggregation and degranulation were measured in whole blood induced by ristocetin, collagen, ADP, and thromboxane A2 (TXA2). The tirofiban-treated group preserved the platelet count and tended to exert these beneficial effects by inhibiting pathologic platelet aggregation induced by TXA2, collagen, and ADP as well as degranulation. Tirofiban may be useful in preserving platelet number and function during clinical VAD use. 相似文献
102.
The purpose of this study is to assess the safety and efficacy of the four known methods of percutaneous tracheostomy. Perioperative, postoperative, and late complication rates were generated for each method after a complete literature review identified 1684 percutaneous tracheostomy patients reported in 40 series. Two methods, the Toye and the guide wire dilator forceps (GWDF) methods, have been the subject of few investigations. Two other methods have been extensively studied. A high perioperative complication rate was calculated for the Rapitrac? method, whereas percutaneous dilational tracheostomy (PDT) has complication rates similar to those reported for standard operative tracheostomy. A retrospective review of 22 patients who underwent PDT at a local community hospital confirmed a “learning curve” for this technique that had been previously suggested. Review of the literature suggests that PDT can be safe and cost-effective for selected patients, but a learning curve for this technique exists that dictates caution, experience, and preparation on the part of any surgeon who wishes to add percutaneous tracheostomy to his or her repertoire. 相似文献
103.
McElroy MK Gerard A Powell FL Prisk GK Sentse N Holverda S West JB 《High altitude medicine & biology》2000,1(3):197-206
In a randomized, double-blind study, 24 sea-level residents drove to 3,800-m altitude in 1 day, and then slept the first night in either ambient air or 24% oxygen, and the second night in the treatment that they did not receive on the first night. Oxygen enrichment, compared with ambient air, resulted in significantly fewer apneas, and significantly less time spent in periodic breathing during the night. The increase in SaO2 between evening and morning was significantly higher after sleeping in the oxygen-enriched atmosphere, compared with ambient air. However, this significant improvement in SaO2 did not persist into mid-day. The overnight treatment did not alter the ventilatory response to hypoxia or to carbon dioxide as measured the following morning. The results suggest that the elevation in SaO2 following overnight oxygen enrichment is probably not due to a change in the control of ventilation, but possibly to differences in subclinical lung pathology. 相似文献
104.
Objective: To describe trends in scooter-related injuries among US youth and compare scooter injuries to those related to in-line skates and skateboards. DESIGN: Retrospective review of data for children 1-19 years old from the National Electronic Injury Surveillance System of the US Consumer Product Safety Commission for 1997-2002. RESULTS: There were an estimated 190,878 scooter-related injuries (95% confidence interval: 145,984-235,773) among children treated in US emergency departments; 90% were in those 15 years old or younger. There was a marked increase in scooter-related injuries in 2000, injuries peaked in 2001, and declined. In 2002, the number of scooter-related injuries was similar to in-line skates and lower than skateboard-related injuries. Scooter- and in-line skate-associated injuries primarily involved children 5-12 years old: rates of scooter-related injuries were higher than rates of in-line skate-associated injuries among those 1-9 years old. Skateboard-related injuries more often involved teens. Forearm fractures accounted for 56% of fractures related to scooters (vs 74% in-line skates and 49% skateboards, chi-square, P < .01). Five percent of children injured using scooters had a closed head injury or skull fracture, similar to in-line skates and skateboards. CONCLUSIONS: The annual number of injuries related to scooters, which peaked in 2001, is now similar to the number of injuries related to in-line skates. Injuries related to scooters primarily involve children 5-12 years old, and forearm fractures are common. These data suggest helmets should be used, and protective equipment should be developed to reduce forearm fractures. 相似文献
105.
Slade M Powell R Rosen A Strathdee G 《Social psychiatry and psychiatric epidemiology》2000,35(2):78-85
Background: Lack of consensus about the meaning of severe mental illness makes it difficult to prioritise the severely mentally ill
for specialist mental health care. The goal of this study was to develop a valid and brief assessment of severity of mental
illness. Method: Six search workshops (n = 57) using consensus techniques developed a draft assessment acceptable to users, carers, practitioners and policy makers.
A two-round Delphi consultation (n = 58) was held to identify consensus on this instrument. Results: Search workshops agreed seven domains relevant to identifying the severely mentally ill: intentional and unintentional self-harm,
risk from and to others, and survival, psychological, and social needs and disabilities. The Delphi consultation indicated
at least agreement with all aspects in both rounds. Conclusions: The Threshold Assessment Grid (TAG) is a brief method of identifying the severely mentally ill, which has adequate face,
concurrent, construct and content validity.
Accepted: 10 November 1999 相似文献
106.
Tiffany L. Sarrafian Jennifer L. Brazzell Matthew Barron Johnathon Aho Ellen Blanco Chelsea Powell Jed Johnson Dennis A. Wigle 《Journal of thoracic disease》2022,14(6):1830
BackgroundMany esophageal pathologies are clinically treated by resection and reconstruction of the esophagus. Surgical esophagectomy remains a morbid procedure and despite minimally invasive advances, has changed little in decades. Novel approaches to esophageal segmental resection and reconstruction are an unmet need.MethodsCircumferential thoracic esophageal transection was performed in both male and female pigs and the defects reconstructed using 5 or 10 cm polyurethane (PU) tubular grafts and stented. A subset were treated with stent only. Animals were survived to 14, 30, 60, and 399 days. Tissues were evaluated histologically, and via non-invasive serial endoscopy and contrast swallowing studies in long-term animals.ResultsLuminal patency was achieved in all animals with no clinical evidence of leak. In short-term animals, there was healing noted in all cases with a variably sized region of ulceration remaining at the most central part of the repaired tube (between the proximal and distal anastomosis). In four long-term animals following stent removal, two resumed normal diet and thrived, while two animals were euthanized prior to the proposed endpoint because of stricture formation and inability to tolerate a normal diet. Re-epithelialization was observed in all groups, and more complete over time.ConclusionsThe PU scaffold provides a matrix across which formation of new tissue can occur. The mechanisms through which this happens remain unclear, but likely a combination of fibrosis and tissue contraction, in conjunction with new tissue formation. 相似文献
107.
108.
Ayers S Zink DL Powell JS Brown CM Grund A Bills GF Platas G Thompson D Singh SB 《Journal of natural products》2008,71(3):457-459
Noreupenifeldin ( 2), a new monotropolone derivative of the bistropolone eupenifeldin ( 1), was isolated from an unidentified ascomycete by bioassay-guided fractionation as part of our search for new anthelmintics. The structure of 1 was confirmed by comparison with literature data. The structure of 2 was elucidated from MS and 1D and 2D NMR data. Compounds 1 and 2 are diastereomers of pycnidione ( 3) and epolone A ( 4), respectively. Compounds 1- 3 were evaluated for their anthelmintic activity against the parasitic worm Hemonchus contortus. Compounds 1 and 3 exhibited modest in vitro activity, showing EC 90 50 and 83 microg/mL, respectively, in reducing motility of L3 larvae of H. contortus. Compound 2 was inactive, indicating that the second tropolone moiety is required for activity. 相似文献
109.
110.
Daniel R. Taber Jamie F. Chriqui Frank M. Perna Lisa M. Powell Sandy J. Slater Frank J. Chaloupka 《Preventive medicine》2013