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81.
FF Cox WJ Morshuis HW Plokker JC Kelder HA van Swieten A Brutel de la Rivière PJ Knaepen FE Vermeulen 《Canadian Metallurgical Quarterly》1996,61(6):1752-7; discussion 1757-8
BACKGROUND: The aim of this study was to identify factors influencing early outcome after surgical treatment of postinfarction ventricular septal rupture. We investigated the influence of proximal or distal rupture location. METHODS: Between 1980 and 1992 109 patients were treated surgically for ventricular septal rupture using a standardized technique. A division in time periods was made. The rupture was categorized according to its anterior or posterior site and proximal or distal location. RESULTS: The 30-day mortality rate was 27.5%. Multivariate logistic regression analysis identified preoperative shock (p = 0.0007) and right atrial oxygen saturation less than 60% (p = 0.021) as predictors for early death; the risk for early death declined over the time periods from 50% to 12.8% (p = 0.0007). Proximal ventricular septal rupture location (p = 0.0092) and interval between infarction and ventricular septal rupture less then 1 day (p = 0.034) were risk factors for the occurrence of preoperative shock. CONCLUSIONS: Proximal ventricular septal rupture location was the main determinant of preoperative cardiogenic shock, which in turn was the strongest predictor of early mortality. Over the time periods a decrease in early mortality was reached. 相似文献
82.
83.
CE Domene EC Amico S Klajner LA Ribeiro MA Santo HW Pinotti 《Canadian Metallurgical Quarterly》1998,53(4):199-201
The Authors report two cases of renal leiomyosarcomas with atypical clinical features. Despite a malignant histological picture, nephron-sparing surgery was performed. The two patients are alive and disease-free at six years and fifteen months respectively. Specific radiologic findings, indications and rationale for conservative treatment are discussed. 相似文献
84.
Macrophage migration inhibitory factor (MIF) was the first cytokine to be described, but for 30 years its role in the immune response remained enigmatic. In recent studies, MIF has been found to be a novel pituitary hormone and the first protein identified to be released from immune cells on glucocorticoid stimulation. Once secreted, MIF counterregulates the immunosuppressive effects of steroids and thus acts as a critical component of the immune system to control both local and systemic immune responses. We report herein the x-ray crystal structure of human MIF to 2.6 angstrom resolution. The protein is a trimer of identical subunits. Each monomer contains two antiparallel alpha-helices that pack against a four-stranded beta-sheet. The monomer has an additional two beta-strands that interact with the beta-sheets of adjacent subunits to form the interface between monomers. The three beta-sheets are arranged to form a barrel containing a solvent-accessible channel that runs through the center of the protein along a molecular 3-fold axis. Electrostatic potential maps reveal that the channel has a positive potential, suggesting that it binds negatively charged molecules. The elucidated structure for MIF is unique among cytokines or hormonal mediators, and suggests that this counterregulator of glucocorticoid action participates in novel ligand-receptor interactions. 相似文献
85.
R Paul S Lorenzl U Koedel B Sporer U Vogel M Frosch HW Pfister 《Canadian Metallurgical Quarterly》1998,44(4):592-600
In this study, we investigated the involvement of matrix metalloproteinases (MMPs) in the pathophysiology of bacterial meningitis. By using an enzyme immunoassay, high concentrations of MMP-9 were detected in the cerebrospinal fluid (CSF) of adult patients with bacterial meningitis but not in controls, and in patients with Guillain-Barré syndrome. Moreover, we observed significantly elevated concentrations of the tissue inhibitor of metalloproteinase-1 (TIMP-1) in the CSF of patients with bacterial meningitis, compared with controls. In a rat model of meningococcal meningitis, intracisternal injection of heat-killed meningococci caused a disruption of the blood-brain barrier (BBB), an increase in intracranial pressure, and CSF pleocytosis paralleled by the occurrence of MMP-9 activity in the CSF 6 hours after meningococcal challenge. The MMP inhibitor batimastat (BB-94) significantly reduced the BBB disruption and the increase in intracranial pressure irrespective of the time of batimastat administration (15 minutes before and 3 hours after meningococcal challenge) but failed to significantly reduce CSF white blood cell counts. In conclusion, our results suggest that MMPs are involved in the alterations of BBB permeability during experimental meningococcal meningitis. 相似文献
86.
JS Odorico DM Heisey BJ Voss DS Steiner SJ Knechtle AM D''Alessandro RM Hoffmann HW Sollinger 《Canadian Metallurgical Quarterly》1998,30(2):276-277
In this study, we demonstrated that Px grafts from donors older than 45 years are associated with an increased risk of developing poor glycemic control and premature loss of Px function. Previous studies corroborate our finding that age of the donor is the principal donor characteristic impacting postoperative Px survival. Whereas prior studies also implicated hyperamylasemia as a factor which contributes adversely to outcome, we were unable to demonstrate a significant influence of donor hyperamylasemia on long-term graft survival, although it did correlate with the degree of immediate postoperative pancreatitis and with the need for oral hypoglycemic agents. Similarly, elevated blood glucoses in the donor, which can be a result of many other factors unrelated to the quality of the graft, did not predict a poor outcome in the recipient. NHB donor pancreata did as well as HB pancreata with regards to all postoperative functional parameters. A marginally increased risk of developing major complications was associated with older donors. Despite the frequent use of non-ideal donors, including older and NHB donors, excellent overall Px graft survival can be achieved. Although the quality of the pancreas graft was not directly addressed in this study, we believe irrespective of hyperglycemia or hyperamylasemia, subjective assessment of organ quality by an experienced transplant surgeon is the most important determinant of suitability. 相似文献
87.
88.
P Engler-Pinto J Gama-Rodrigues F Pinatel Lopasso A Castro Cordeiro HW Pinotti 《Canadian Metallurgical Quarterly》1995,50(6):320-325
This study is to analyze gastric emptying (GE) of 99mTc tagged solid meals in 43 gastric ulcer (GU), 16 duodenal ulcer (DU) patients, and 15 normal subjects. Diagnosis of active ulcers had been made through high gastrointestinal endoscopy. The patients with GU were divided into three groups according to Johnson's classification. Gastric contents were measured at 15 minute intervals over a period of 150 minutes, with the person standing in front of a gamma-counter. The GE curve was obtained from the mean percentile of radioactivity of all the groups measured at 15 minute intervals. Results were submitted to statistical analysis. Significant delay in GE in DU patients compared to normals, type II and Type III group. However, GE of type I GU was not statistically different from the DU group nor of types II and III GU, occupying an intermediate e position. 相似文献
89.
Mycophenolate mofetil (the morpholinoethyl ester of mycophenolic acid) inhibits de novo purine synthesis via the inhibition of inosine monophosphate dehydrogenase. Its selective lymphocyte antiproliferative effects involve both T and B cells, preventing antibody formation. Mycophenolate mofetil has immuno-suppressive effects alone, but is used most commonly in combination with other immunosuppressants. Mycophenolate mofetil, in combination with cyclosporin and corticosteroids, has been studied in large, randomised clinical trials involving nearly 1500 renal allograft transplant recipients. These trials demonstrated that mycophenolate mofetil is significantly more effective in reducing treatment failure and acute rejection episodes than placebo or azathioprine. Additionally, mycophenolate mofetil may be able to reduce the occurrence of chronic rejection. Mycophenolate mofetil is relatively well tolerated. The most common adverse effect reported is gastrointestinal intolerance; haematological aberrations have also been noted. The reversible cytostatic action of mycophenolate mofetil allows for dose adjustment or discontinuation, preventing serious toxicity or an overly suppressed immune system. Cytomegalovirus tissue invasive disease and the development of malignancies are concerns that merit evaluation in long term follow-up studies. Mycophenolate mofetil does not cause the adverse effects typically associated with other commercially available immunosuppressant medications such as nephrotoxicity, hepatotoxicity, hypertension, nervous system disturbances, electrolyte abnormalities, skin disorders, hyperglycaemia, hyperuricaemia, hypercholesterolaemia, lipid disorders and structural bone loss. Based on preliminary information, a positive benefit-risk ratio has been demonstrated with the use of mycophenolate mofetil in the prophylaxis of rejection in cadaveric renal allograft transplantation. Data from studies in other types of organ transplants are promising, but are too limited to draw clear conclusions. Long term follow-up studies are required to confirm these observations. Although mycophenolate mofetil is expensive, the beneficial effects on the reduction of rejection, treatment failure and related expenses suggest that it is most likely to be cost effective. 相似文献
90.
TL Toth SG Baka LL Veeck HW Jones S Muasher SE Lanzendorf 《Canadian Metallurgical Quarterly》1994,61(5):891-894
OBJECTIVE: To determine the potential for in vitro maturation, fertilization, and cleavage after cryopreservation of immature, prophase I human oocytes. DESIGN: Immature oocytes obtained in excess of the number required by the patient were randomized and cryopreserved at the prophase I stage or cultured as control. After thawing and maturation in vitro, test and control oocytes were inseminated with husband's sperm and evaluated for fertilization and cleavage in vitro. SETTING: In vitro fertilization program. PATIENTS: Consenting patients undergoing controlled ovarian hyperstimulation for the purposes of IVF. MAIN OUTCOME MEASURES: Rates of maturation to metaphase II, fertilization, and cleavage were compared between control and cryopreserved oocytes. RESULTS: Upon thaw, 58.5% (72/123) of prophase I oocytes were viable. Control oocytes demonstrated a 74.8% (98/131) maturation rate to metaphase II, a 56.5% (52/92) fertilization rate, and an 11.5% (6/52) blastocyst rate. Cryopreserved oocytes showed a 83.3% (60/72) rate of maturation, a 57.7% (30/52) fertilization rate, and a 3.3% (1/30) blastocyst rate. No significant differences were noted between any of these parameters. CONCLUSIONS: These results demonstrate that prophase I oocytes from stimulated IVF cycles are able to survive cryopreservation and resume meiosis to achieve full nuclear maturation post-thaw. In addition, cryopreserved oocytes retain the same capacity for fertilization and development as control oocytes. 相似文献