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1.
Ticagrelor is a cornerstone of modern antithrombotic therapy alongside aspirin in patients with acute coronary syndrome and after percutaneous coronary intervention. Adverse effects such as bleeding and dyspnea have been associated with premature ticagrelor discontinuation, which may limit any potential advantage of ticagrelor over clopidogrel. The randomized trials of ticagrelor captured adverse events, offering the opportunity to more precisely quantify these effects across studies. Therefore, a meta-analysis of 4 randomized clinical trials of ticagrelor conducted between January 2007 and June 2017 was performed to quantify the incidence and causes of premature ticagrelor discontinuation. Among 66,870 patients followed for a median 18 months, premature ticagrelor discontinuation was seen in 25%; bleeding was the most common cause of discontinuation followed by dyspnea. Versus the comparators, the relative risk of dyspnea-related discontinuation during follow-up was 6.4-fold higher, the relative risk of bleeding was 3.2-fold higher, and the relative risk of discontinuation due to any adverse event was 59% higher for patients receiving ticagrelor. Understanding these potential barriers to adherence to ticagrelor is crucial for informed patient-physician decision making and can inform future efforts to improve ticagrelor adherence. This review discusses the incidence, causes, and biological mechanisms of ticagrelor-related adverse effects and offers strategies to improve adherence to ticagrelor.  相似文献   
2.
MATTHEW  B.  COLLIER  C.  ANDERSON  ENGH  JR.  JAMES  P.  MCAULEY  STUART  D.  GINN  GERARD  A.  ENGH  蔡迅梓 《骨科动态》2006,2(2):93-99
背景:从关节和胫骨假体聚乙烯衬垫后表面转移磨损碎屑,是全膝关节置换术后假体周围骨溶解的主要原因。全膝人工关节假体设计随时问而发生变化,例如对胫骨盘近端表面的粗糙度和聚乙烯衬垫的灭菌方法。我们假设胫骨盘表面抛光和采用空气中γ射线照射之外的其他方法对衬垫灭菌,可降低骨溶解的发生率。方法:从1987年至1998年,我们采用后十字韧带保留型的解剖型组配式全膝人工关节假体系列。对300名患者施行365例全膝关节置换术。术后5至10年,对这些患者的膝关节摄正、侧位X线片。由两位关节置换专家对X线片上的骨溶解状况进行单独评定(骨溶解的界定标准为假体周围存在边缘清晰的非线性松质骨丢失区)。结果:在粗糙表面的胫骨盘的242例膝关节中,使用空气中γ射线照射灭菌的衬垫固定,有34%(82例)骨溶解阳性。用惰性气体中γ射线照射或没有照射的衬垫与抛光表面连接的98例膝关节中,有9%(9例)骨溶解阳性。骨溶解与六项因素相关,这些因素为:一项与患者(男性)相关、一项与胫骨盘(近端表面抛光)相关、三项与聚乙烯衬垫(加工的原材料、灭菌方法及存放时间)相关及一项与手术技术(股骨假体与胫骨假体间的过伸)相关。结论:在这类假体设计中,胫骨盘近端表面采用抛光及衬垫采用更为先进的灭菌方法(不用空气中γ射线照射灭菌)能显著减少骨溶解的发生率,但不能避免骨溶解。  相似文献   
3.
Objective. The safety and efficacy of intrathecal (IT) ziconotide was studied in a randomized, double‐blind, placebo‐controlled trial. Materials and Methods. Patients (169 ziconotide, 86 placebo) with severe chronic nonmalignant pain unresponsive to conventional therapy and a visual analog scale of pain intensity (VASPI score) ≥ 50 mm were treated over a 6‐day period in an inpatient hospital setting. Initial starting dose was 0.4 µg/hour and was titrated to analgesia or intolerance (maximum dose 7.0 µg/hour). The starting and maximum doses were reduced to 0.1 µg/hour and 2.4 µg/hour, respectively, due to adverse events (AEs). Results. The mean percent reduction in VASPI score from baseline was 31.2% and 6.0% for ziconotide‐ and placebo‐treated patients, respectively (p ≤ 0.001). During the initial titration phase, a significantly greater percentage of patients in the ziconotide group compared to the placebo group reported AEs, including abnormal gait, amblyopia, dizziness, nausea, nystagmus, pain, urinary retention, and vomiting. Conclusion. Ziconotide provided significant analgesia in patients for whom conventional therapy failed. However, there was a considerable incidence of ziconotide‐associated AEs due to the rapid titration and high doses administered.  相似文献   
4.
Haaga  JR; Beale  SM 《Radiology》1986,161(3):829-830
By injecting small amounts of CO2 through a needle, one can move bowel or bladder from the intended path of instruments during interventional procedures. The technique worked well in six of seven cases in the pelvis and retroperitoneum; it was not effective in the mediastinum or midabdomen (n = 6).  相似文献   
5.
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
6.
A Dose-Response Analysis of Methoxychlor-Induced Alterationsof Reproductive Development and Function in the Rat. GRAY, L.E., JR., OSTBY, J., FERRELL, J., REHNBERG, G., LINDER, R., COOPER,R., GOLDMAN, J., SLOTT, V., AND LASKEY, J. (1989). Fundam. Appl.Toxicol12, 92–108. In the present study rats were dosed fromweaning, through puberty and gestation, to Day 15 of lactationwith methoxychlor at 25, 50, 100, or 200 mg/kg/day. Morphologicallandmarks of puberty were measured, including the ages at vaginalopening, first estrus, and first estrous cycle in females andat preputial separation in males. In the female, estrous cyclicity,fertility, litter size, number of implantation sites, organweights, and ovarian and uterine histology were also measured.The viability of the offspring (F1) and their fertility wereevaluated using a continuous breeding protocol. Males were necropsiedafter breeding, the reproductive organs were weighed, and thecauda epididymal sperm counts were determined. One testis wasused for histopathology, while the other was used to quantifyinterstitial fluid (IF) content, IF testosterone concentration,and testicular sperm production. Testosterone and an drogen-bindingprotein were measured in the caput epididymis, and sperm motilityand morphology were evaluated from a caudal sample. The serumand pituitary were saved for hormonal determinations. Methoxychloraccelerated the age at vaginal opening and first estrus, andthe vaginal smears were cornified. Growth was retarded at 100and 200 mg/kg/day and fertility was reduced when the femaleswere bred with untreated or similarly treated males. In thehighest- dose group, the mated females went from constant estrusinto pseudopregnancy following mating, but they had no implants.In males, methoxychlor treatment markedly reduced growth, seminalvesicle weight, cauda epididymal weight, caudal sperm content,and pituitary weight. Puberty was delayed in the two highest-dosagegroups. Testicular sperm measures were much less affected thancaudal measures. Testis weight and histology were slightly affected,and testicular sperm production, sperm morphology, and motilitywere unaffected. Endocrine function of the testes and pituitarywas altered by methoxychlor administration. Leydig cell testosteroneproduction, in response to human chorionic gonadotropin challenge,was reduced and pituitary levels of prolactin, thyroid-stimulatinghormone (TSH), and follicle-stimulating hormone (FSH) were altered.In contrast, serum levels of prolactin, FSH, and luteinizinghormone were unaffected. Serum TSH was reduced by 50% of controlat 100 and 200 mg/kg/day, while pituitary levels were increased.Gonadotropin-releasing hormone concentration in the mediobasalhypothalamus was also elevated. In spite of the many reproductivealterations, the fertility of treated males was not reducedwhen they were mated with untreated females. Growth and viabilityof the offspring (F1) from the 50 mg/kg/day treatment groupwere normal, but in the females, vaginal opening was accelerated,estrous cyclicity was abnormal in the rats during middle age,and fecundity was reduced.  相似文献   
7.
BACKGROUND/OBJECTIVE: The efficacy of a direct factor (F)Xa inhibitor, ZK-807834, was compared with indirect inhibition by enoxaparin for inhibition and deaggregation of acute platelet-rich thrombi in a well-characterized porcine carotid injury model. METHODS: A crush injury was performed on a randomly chosen carotid artery and the thrombus allowed to propagate for 30 min. Pigs then received intravenous drug for 35 min: ZK-807834-Dose 1 (40 microg kg(-1) bolus + 1.5 microg kg(-1) min(-1) infusion, n=6); ZK-807834-Dose 2 (20 microg kg(-1) bolus + 0.75 microg kg(-1) min(-1) infusion; n=6); enoxaparin (1 mg kg(-1) bolus; n=6); or saline (n=6). Five minutes after drug initiation, the contralateral artery was injured. Thrombus size was monitored by scintillation detection of autologous 111In-platelets. RESULTS: The prothrombin time ratio was 2.2 +/- 0.1; 1.4 +/- 0.3; 1.2 +/- 0.9 and 1.1 +/- 0.2, respectively. ZK-807834-Dose 1 significantly inhibited carotid platelet deposition (525 +/- 226 x 10(6) cm(-2); P = 0.008), whereas ZK-807834-Dose 2 (2325 +/- 768) and enoxaparin (1236 +/- 383) were not different from saline (2776 +/- 642). Thrombus deaggregation was greatest for animals receiving ZK-807834-Dose 1 (473 +/- 185). Neither ZK-807834-Dose 2 (1588 +/- 480) nor enoxaparin (1618 +/- 686) was different from saline control (2222 +/- 598). CONCLUSIONS: Direct FXa inhibition with ZK-807834, at a prothrombin time ratio of 2.2, effectively inhibits thrombosis and promptly deaggregates thrombi induced by arterial injury. In contrast, indirect FXa inhibition with enoxaparin was ineffective.  相似文献   
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10.
Researchers have demonstrated that certain types of pain coping are correlated with less pain severity and disability and that there are differences between Caucasians and African-American pain patients in their use of specific coping strategies. However, the extent to which racial group differences exist in the associations between pain coping strategies and pain severity, interference, and disability is unclear. Furthermore, the role of education in these associations is uncertain. We recruited a diverse community sample of individuals with chronic pain and their spouses to examine this issue (N = 105). Participants completed the Coping Strategies Questionnaire, Multidimensional Pain Inventory, and Sickness Impact Profile. Results showed that African-American participants reported significantly more pain severity, interference, and disability and reported using diverting attention and prayer and hoping pain-coping strategies significantly more often than Caucasian participants; however, only the racial group difference in prayer and hoping remained when controlling for education. We also examined whether race and education interacted with coping strategies in relating to pain and disability. Significant three-way interactions were found for physical and psychosocial disability, suggesting that educational level should be included in analyses exploring racial group differences. The results suggest the need for pain treatments that take into account the educational and cultural context of pain. PERSPECTIVE: This article demonstrates that demographic variables such as race and education should be considered together when evaluating the effectiveness of coping with pain. The findings have the potential to enhance research and clinical practice with diverse groups.  相似文献   
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