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The benefits of surgical correction of mitral incompetence were assessed in 51 patients by comparing pre and postoperative catheter and quantitative angiographic results. The mean age of the patients was 43.5 +/- 12.3 years. The mitral lesions were elongation or ruptured chordae (27 cases), valvular perforation due to endocarditis (1 case) and the usual rheumatic disease in 23 cases. Hemodynamic investigation was carried out on average 2 months before operation and 29 +/- 22 months after surgery. The following angiographic parameters were measured : indexed end diastolic and end systolic volumes (EDV and ESV), ejection fraction (EF), myocardial mass (MM) and its ratio to EDV (hypertrophy coefficient : HC) and the geometry of the ventricle as assessed by diastolic and systolic coefficients of excentricity (DE and SE). Surgery comprised 13 mitral valvuloplasties and 38 valve replacements. Patients who suffered perioperative myocardial infarction or who had a residual valvular lesion were excluded from the study. After surgery, the hemodynamic state was considerably improved with a significant decrease in pulmonary capillary pressures (11 +/- 5 compared to 17 +/- 6 mmHg, p less than 0.09) and mean pulmonary artery pressures (19 +/- 7 compared to 27 +/- 11, p less than 0.01) and increase in cardiac index (2.8 +/- 0.7 compared to 2.3 +/- 0.6 l/min/m2, p less than 0.01). There was an associated decrease in ventricular volumes (EDV : 115 +/- 44 compared to 165 +/- 43, p less than 0.01) (ESV : 60 +/- 39 compared to 77 +/- 22, p less than 0.001). The reduction in myocardial mass was less spectacular (129 +/- 40 compared to 148 +/- 32, p less than 0.01) with a resulting increase in the HC (1.10 +/- 0.26 compared to 0.88 +/- 0.17, p less than 0.001). The geometry of the LV was less spherical in diastole (DE 0.76 +/- 0.08 compared to 0.70 +/- 0.08, p less than 0.001) and in systole (SE = 0.83 +/- 0.06 compared to 0.77 +/- 0.08, p less than 0.001). The EF fell slightly but this was not statistically significant (0.51 +/- 0.13 compared to 0.53 +/- 0.09 NS). The surgical result of 14 patients with PCP greater than or equal to 13 mmHg was considered hemodynamically incomplete, and this was confirmed by a lower cardiac index than in the remaining 37 patients (2.4 +/- 0.5 compared to 3.0 +/- 0.7, p less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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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   
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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   
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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   
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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   
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Five patients with optic neuropathy, four vascular and one demyelinating, are described who each complained of an unusual symptom. Bright flashes of light (phosphenes) occurred in the affected eyes and were evoked by sudden unexpected sounds. Movement of the eye alone did not reproduce the symptom. In all patients the phenomenon was sufficiently prominent to interfere with sleep and was the main complaint of one patient. An anticonvulsant (phenytoin) greatly reduced the frequency and intensity of the phosphene in one patient.  相似文献   
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