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91.
3-Hydroxypropyl flufenamide (Flu-HPA) is one of a series of flufenamic acid derivatives that enhances blood clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The profibrinolytic activity of Flu-HPA in clot lysis assays was found to be dependent on plasminogen. The influence of Flu-HPA on the ability of purified alpha 2-antiplasmin to inhibit purified plasmin was studied. Plasmin activity was determined using 125I-fibrin plates or the spectrophotometric tripeptide substrate, Val-Leu-Lys-paranitroanilide. At Flu-HPA concentrations greater than 1 mM, the inhibitory activity of alpha 2-antiplasmin was abolished in a time-dependent and concentration- dependent manner. The influence of Flu-HPA on the ability of purified Cl inhibitor to inhibit purified plasma kallikrein and beta-Factor XIIa was also studied. Cl inhibitor activity was abolished by Flu-HPA at concentrations greater than 2 mM. Notably, Flu-HPA up to 60 mM did not affect the amidolytic activities of plasmin, kallikrein, or beta-Factor XIIa. Flu-HPA did not release enzyme activity from preformed complexes of either alpha 2-antiplasmin and plasmin of Cl inhibitor and kallikrein. A water-soluble derivative of flufenamic acid, N-flufenamyl- glutamic acid, also inactivated alpha 2-antiplasm and Cl inhibitor. This inactivation was shown to be reversible. These results indicate that synthetic fibrinolytic compounds such as flufenamic acid derivatives may promote fibrinolysis by directly inactivating alpha 2- antiplasmin and Cl inhibitor. 相似文献
92.
Graft-versus-host disease (GVHD) is currently encountered after bone marrow transplantation and transfusion. GVHD associated with transfusion (TA-GVHD) in apparently immunocompetent recipients has been recently reported with increasing frequency. A consistent finding in many of these cases is that the recipient received blood from a donor homozygous for one of the recipient's HLA haplotypes. However, the observed frequency of TA-GVHD is much lower than the estimated probability of this donor/recipient combination. The potential role of recipient immune responses in controlling TA-GVHD was investigated using an analogous murine model in which GVHD is induced by the injection of parental lymphoid cells into unirradiated F1 hybrid recipients. The effect of various immune manipulations of the recipient of GVHD induction was assessed by determining the number of donor lymphoid cells required to induce GVHD responses. Whereas depletion of recipient CD4+ cells increased the number of donor cells needed to induce GVHD, depletion of recipient CD8+ and natural killer cells resulted in fewer donor cells being needed to induce a GVHD response. These studies suggest a central role for functioning recipient CD8 and natural killer cells in the down-regulation of TA-GVHD development in recipients. 相似文献
93.
Injuries to peripheral nerves are common and cause life-changing problems for patients alongside high social and health care costs for society. Current clinical treatment of peripheral nerve injuries predominantly relies on sacrificing a section of nerve from elsewhere in the body to provide a graft at the injury site. Much work has been done to develop a bioengineered nerve graft, precluding sacrifice of a functional nerve. Stem cells are prime candidates as accelerators of regeneration in these nerve grafts. This review examines the potential of adipose-derived stem cells to improve nerve repair assisted by bioengineered nerve grafts. 相似文献
94.
95.
EG Burden RW Walker DJ Ferguson AMF Goubran JR Howell JB John F Khan JS McGrath JP Evans 《Annals of the Royal College of Surgeons of England》2021,103(3):173
IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery. 相似文献
96.
Ricardo Ruiz‐Villaverde Angela Ayn‐Rodriguez Jose Maria Llamas‐Molina Jose Carlos Ruiz‐Carrascosa 《Dermatologic therapy》2020,33(3)
Obesity and increased waist circumference are associated with all the factors constituting the metabolic syndrome (type 2 diabetes, sleep apnea, hypertension, dyslipidaemia, acute myocardial infarction…) and also with an increased mortality. One of the main methods to determine the obesity is through the body mass index (BMI), which is calculated as weight in kilograms, divided by height in metres squared. Obesity is considered to be when the BMI is greater than 30 kg/m2. The association with psoriasis has been revealed in different epidemiological studies and clinical trials and mainly affects patients who develop more severe forms of psoriasis. We report an obese patient under treatment with Risankizumab with successful and sustained response over 52 weeks, as a very promising therapeutic approach as an efficient treatment in this patients 相似文献
97.
The efficacy of the non-steroidal anti-inflammatory analgesic, ketorolac (Toradol), was investigated in 52 day case patients undergoing removal of impacted third molar teeth under intravenous sedation and local analgesia. The study was double-blind, randomized and placebo-controlled. A single 30 mg dose of ketorolac was administered intravenously just prior to induction of sedation with midazolam. Ketorolac was well tolerated and provided good postoperative analgesia. It is suggested that ketorolac is a useful addition to the analgesic armamentarium and appropriately prescribed, provides good pain relief following day case oral surgery. 相似文献
98.
Because T-cell responses are critical for defense against viral infections, the synthetic P18 peptide (RIQRGPGRAFVTIGK) and active component of gp160 protein has previously been shown to induce cytotoxic and helper T-lymphocyte responses. In order to further define the T-helper cells, responses which are known to play a role in enhancing the immunological response to foreign antigen, we studied the response of individuals immunized with HIV gp160 candidate vaccines. We investigated the proliferative cellular response of peripheral blood mononuclear cells (PBMC) derived from individuals immunized with gp160 antigens in three different protocols. We found a PBMC proliferative response to synthetic P18 peptide in healthy immunized individuals induced by gp160 antigen with or without vaccinia virus. There was correlation between the proliferative response to P18 peptide and other antigens such as HIV-like proteins and gp160 molecule. HLA-DR typing revealed the possible presentation of P18 peptide by several different class II molecules. Since these class II molecules occur frequently in the general population, P18 peptide appears to contain broadly reactive epitopes and thus is presented by mutiple HLA class II molecules. Due to its broad reactivity P18 peptide is one of the candidates for inclusion as a subunit vaccine against HIV-1. 相似文献
99.
肿瘤治疗存在的问题及中西医结合的研究重点 总被引:17,自引:3,他引:17
目前的肿瘤治疗主要存在以下几个问题:(1)肿瘤的过度治疗普遍存在;(2)急功近利而缺乏长远规划;(3)综合治疗缺乏合理的内涵;(4)缺少有效的个体化治疗方案;(5)对中医药的优势认识不足、发挥不够。中西医结合在肿瘤防治中大有可为,应重点围绕以下几个方面开展研究工作:(1)加强中医对恶性肿瘤基础知识的认识和研究;(2)加强中西医结合治疗肿瘤合理化、规范化方案的研究;(3)加强中西医结合治疗恶性肿瘤疗效标准的研究;(4)加强中西医结合防治肿瘤术后复发、转移的研究。 相似文献
100.
Translumbar retroperitoneal endoscopy: an alternative in the follow-up and management of drained infected pancreatic necrosis 总被引:4,自引:0,他引:4
Castellanos G Piñero A Serrano A Llamas C Fuster M Fernandez JA Parrilla P 《Archives of surgery (Chicago, Ill. : 1960)》2005,140(10):952-955
BACKGROUND: The follow-up of drained infected pancreatic necrosis (IPN) is usually done with data on the patient's clinical evolution and information obtained from serial helical computed tomographic scans. Management often requires necrosectomies and periodic debridements. HYPOTHESIS: Translumbar retroperitoneal endoscopy is effective in the management of drained IPN. DESIGN: A prospective observational study. SETTING: University tertiary care hospital. PATIENTS: A series of 11 consecutive patients with drained IPN undergoing postoperative follow-up with translumbar retroperitoneal endoscopy. INTERVENTIONS: Initially, the IPN was drained via the posterior extraperitoneal translumbar approach; then, a superficial necrosectomy was performed during the same surgical intervention by flushing and endoscopic aspiration; and, finally, a lavage and drainage system was fitted. In the immediate postoperative period, for management of the IPN, we removed the drainage tube and inserted a flexible endoscope as far as the pancreatic area to eliminate the infected necrotic material by flushing and aspiration. MAIN OUTCOME MEASURES: In these patients, we studied control of the infection of the pancreatic area, quantification variables of the necrosectomy, technique-related morbidity and mortality, and the need for subsequent operations. RESULTS: The 11 patients studied showed good results regarding the control and complete elimination of the infected necrosis. There was no technique-related morbidity or mortality or need for subsequent operations. CONCLUSION: Translumbar retroperitoneal endoscopy allows exploration of the retroperitoneal space under direct visual guidance, facilitates lavage and aspiration, avoids subsequent surgical operations for debridement, decreases the need for repeated computed tomographic scans to evaluate the evolution of the IPN, and has no added morbidity or mortality. 相似文献