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991.
992.
Ciochină AD Bredeţean O Dimitriu DC Iacob G 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2009,113(1):279-285
The aim of this paper is to summarize few aspects and underline some difficulties that hemocompatibility testing come up. The purpose of hemocompatibility testing is to look for possible undesirable changes in the blood caused directly by a medical device, by chemicals leaching from a device or biomaterials. Undesirable effects of device materials on the blood may include alterations in coagulation parameters, thrombus formation, hemolysis, and immunological changes. For each different event the literature is rich in showing tests, not different in principle, but in testing conditions. ISO 10993-4 describes hemocompatibility tests in five different categories (thrombosis, coagulation, platelets, hematology, and immunology). Here we put together the tests that ISO 10993 and/or American Society for Testing and Materials (ASTM) suggest to evaluate hemocompatibility and we emphases on their utility for magnetic nanoparticules testing. The individual tests are not discussed in detail; they may be performed either in vivo or, preferably, in vitro. For each test we made few considerations with criticism. There is still some uncertainty with respect to what is actually required by the regulatory authorities for the hemocompatibility test, and there is still no harmony between ASTM and ISO 10993 regulations regarding some aspects to be standardised. 相似文献
993.
Background
The decision to perform laparotomy in blunt trauma patients is often difficult owing to pelvic fractures; however, once the decision is made, delay or failure to perform laparotomy could affect morbidity and mortality. We sought to identify predictors of laparotomy and mortality in polytrauma patients with pelvic fractures.Methods
We divided 390 blunt polytrauma patients (Injury Severity Score [ISS] ≥ 16) with pelvic fractures into laparotomy (n = 56) and nonlaparotomy (n = 334) groups. We assessed the role of the following variables in predicting laparotomy and mortality: age, sex, hypotension, fluid and blood transfusions, positive abdominal computed tomography (CT) scans or focused assessment with sonography for trauma (FAST) examination, pelvic fracture severity and ISS. We analyzed the data using Student t and χ2 tests, followed by logistic regression analysis.Results
Mortality was higher in the laparotomy group than the nonlaparotomy group (28.6% v. 12.9%; overall mortality 15.1%). The laparotomy group had higher mean ISS (36.9 v. 24.9), higher mean abbreviated injury scores (AIS) for the abdomen (2.6 v. 0.9) and chest (3.4 v. 1.6), lower mean initial hemoglobin levels (105.2 v. 127.0 g/L), higher mean crystalloid (4249 v. 3436 mL) and blood transfusion volumes over 4 hours (12.1 v. 3.9 units), more frequent hypotension (44.6 v. 18.0%) and a higher percentage of positive CT scans (67.9% v. 28.4%) and FAST examination results (42.9% v. 3.3%) than the nonlaparotomy group. Age (mean 53.7 v. 41.5 yr); ISS (mean 39.0 v. 24.4); AIS for the head (mean 3.2 v. 1.7), abdomen (mean 1.6 v. 1.1), chest (mean 2.7 v. 1.8) and pelvis (mean 3.1 v. 2.6); crystalloid (mean 5157.3 v. 3266.4 mL) and blood transfusion volumes over 4 hours (mean 13.1 v. 3.7) and initial hypotension (61% v. 14.8%) were all greater among patients who died than those who survived. Mean initial hemoglobin levels were lower among patients who died than among those who survived (111.1 v. 126.2 g/L). Age, the AIS for the head, initial hypotension and low initial hemoglobin levels were highly predictive of mortality, whereas low initial hemoglobin levels, a positive FAST examination and high AIS for the abdomen and chest were all highly predictive of laparotomy.Conclusion
Among the polytrauma patients with pelvic fractures, 14.3% underwent laparotomy, and mortality was higher among these patients than among those who did not have the procedure. The predictors of laparotomy and mortality are similar to those anticipated in patients without pelvic fractures. 相似文献994.
Zainab Al Balushi Sabrina Bulduc Claudia Mulleur Michel Lallier 《Journal of pediatric surgery》2009,44(5):949-952
Purpose
Desmoplastic small round cell tumor (DSRCT) is a rare, highly aggressive malignancy with distinctive histologic and immunohistochemical features occurring in a young population with a male predominance. The tumor appears to arise as masses in the abdominal cavity without a clear visceral origin. Five patients with DSRCT were treated as usual with combined chemoradiation and surgery. In addition, in our center, patients underwent autologous bone marrow transplant (BMT), which is a novel approach to this disease.Methods
Charts of 5 patients (4 males, mean age of 11 years) treated between 2000 and 2007 were reviewed. The diagnosis of DSRCT was made on the basis of clinical examination, computed tomographic scan, and explorative laparotomy with biopsy, and biochemical markers were negative. All patients were treated with aggressive chemoradiation and surgery. Three patients also had autologous BMT.Results
Three patients (BMT recipients) responded to treatment. The responding patients had surgery with the intent of removing all disease. Two patients died of their cancer, neither of whom underwent BMT.Conclusion
The patients DSRCT are sensitive to an aggressive combination of chemotherapy, surgical debulking, and radiation therapy, followed by autologous BMT. It appears that this new multifaceted treatment offers good palliation, which may prolong survival and a possible cure. 相似文献995.
Dana M. Hartl MD PhD Abir Al Ghuzlan MD Linda Chami MD Sophie Leboulleux MD Martin Schlumberger MD PhD Jean-Paul Travagli MD 《Annals of surgical oncology》2009,16(9):2595-2601
Background The incidence of cancer in thyroglossal duct cysts (TDC) is low and management is controversial. The objective was to report
the rate of multifocality, lymph node metastases, and long-term results for TDC carcinomas in adults.
Materials and Methods Files from 1979 to 2008 were reviewed for tumor stage, multifocality in the lobes, lymph node metastases, treatment, and follow-up.
Results A total of 18 patients (13 females, 5 males, average age 41.5 years) were treated for papillary carcinoma arising in a TDC.
Of these, 15 underwent total thyroidectomy, 1 isthmusectomy and 2 a Sistrunk procedure only. Also, 16 patients underwent neck
dissection of the central and/or lateral compartments. Tumors were staged pT1 (n = 15), pT3 (n = 3), pN0 (n = 4), pN1a (n = 3), pN1b (n = 9), Nx (n = 2), M0 (n = 17), and M1 (n = 1, lung metastases). Tumor foci were found in the thyroid lobes in 9 of 16 patients(56%). Lymph node metastases were found
in 12 of 16 (75%). Nodes were positive in 6 of 15 central compartment dissections (40%) and in 9 of 15 lateral neck dissections
(60%). Metastases to the lateral compartment, with no central compartment metastasis, were found in 6 of 15 patients (40%).
Radioiodine was administered to 12 patients. Median follow-up was 12 years (range 1–22 years). All had negative ultrasound.
Stimulated Tg levels available for 11 patients were undetectable for 10 and 2 ng/mL for the remaining patient.
Conclusions This series shows a high rate of thyroid lobe foci and lymph node metastases but an excellent long-term outcome, characteristics
shared with classic papillary carcinoma. Lateral neck metastases seem to be more frequent. These findings are in favor of
following the current guidelines for differentiated thyroid cancer in general for the treatment of these rare tumors. 相似文献
996.
997.
Al Mamun A Alati R O'Callaghan M Hayatbakhsh MR O'Callaghan FV Najman JM Williams GM Bor W 《Addiction (Abingdon, England)》2007,102(4):647-654
AIMS: To examine whether there is evidence of an independent association between childhood sexual abuse (CSA) and nicotine disorder in youth and to explore the mechanisms underlying this association in a prospective cohort study. DESIGN: Birth cohort study followed-up to 21 years. SETTING: One of two major obstetric hospitals in Brisbane, Australia. PARTICIPANTS: The Mater-University of Queensland Study of Pregnancy involves a prospective birth cohort from a population-based sample involving 7223 singletons whose mothers were enrolled between 1981 and 1984 at the first antenatal visit. The present cohort consisted of a subgroup of 2571 youth who completed the life-time version of the Composite International Diagnostic Interview--computerized version (CIDI-Auto) at the 21-year follow-up. MEASUREMENTS: Nicotine disorder was measured based on Diagnostic and Statistical Manual version IV (DSM-IV) diagnostic criteria and measures of CSA, including retrospective self-reports of rape, were obtained at 21 years. Results Of 2571 young adults, 16.6% met the criteria for either dependence (12.8%) or withdrawal (8.5%). Non-penetrative sexual abuse was reported by 15.5% of respondents and 8.0% reported penetrative sexual abuse. For any types of sexual abuse including non-penetrative, penetrative and self-reported rape before age 16 years, young adults had significantly higher rates of nicotine disorder than young adults who did not experience CSA. This relationship was independent and appeared direct after adjustment for a range of potential confounding and mediating factors. CONCLUSIONS: This study shows that CSA is associated with young adult nicotine disorder. The results extend the public health significance of findings in this area and highlight the importance of not only intensifying public health efforts to address substance use problems among those who have experienced CSA, but of early intervention, so that emerging risky behaviours may be targeted in the earliest stages. 相似文献
998.
Fawzy ME Shoukri M Al Buraiki J Hassan W El Widaal H Kharabsheh S Al Sanei A Canver C 《The Journal of heart valve disease》2007,16(5):454-460
BACKGROUND AND AIM OF THE STUDy: Long-term echocardiographic follow up studies of mitral balloon valvuloplasty (MBV) are scarce. The study aim was to assess the long-term results (up to 17 years) of MBV and to identify predictors of restenosis and event-free survival. METHODS: The immediate and long-term clinical and echocardiographic results for 520 consecutive patients (mean age 31 +/- 11 years) who underwent successful MBV for severe mitral stenosis (MS) and were followed up for a mean of 7.3 +/- 4.35 years (range: 1 to 17 years) after MBV, were reported. RESULTS: Immediately after MBV, the mitral valve area (MVA) was increased from 0.92 +/- 0.17 to 1.96 +/- 0.29 cm2 (p < 0.0001). Restenosis occurred in 133 patients (25.6%), and was less frequent (16.7%) in patients with a low mitral echo score (MES < or = 8). Actuarial freedom from restenosis at 10, 15, and 17 years was 73 +/- 2%, 43 +/- 4%, and 23 +/- 6%, respectively, and was significantly higher in patients with MES < or = 8 (84 +/- 2%, 52 +/- 6%, and 36 +/- 9%, respectively; p < 0.001). Event-free survival (death, redo MBV, mitral valve replacement, NYHA class III or IV) at 10, 15, and 17 years was 82 +/- 2%, 45 +/- 5%, and 31 +/- 6% respectively, and was significantly higher for patients with MES < or = 8 (90 +/- 2%, 60 +/- 5%, and 51 +/- 8%, respectively; p < 0.001). Cox regression analysis identified MES > 8 (p < 0.0001) and post-procedure MVA (p = 0.044) as predictors of restenosis, and MES < or = 8 (p < 0.0001), age (p < 0.0001), and post-procedure MVA (p = 0.016) as predictors of event-free survival. CONCLUSION: MBV provides excellent long-term results for selected patients with MS. The long-term outcome of this procedure can be predicted from the baseline clinical and echocardiographic characteristics of the mitral valve. 相似文献
999.
1000.
Le Moing V Thiébaut R Chêne G Sobel A Massip P Collin F Meyohas M Al Kaïed F Leport C Raffi F;ANRS CO 《HIV medicine》2007,8(3):156-163
BACKGROUND: The increase in CD4 count may reach a plateau after some duration of virological response to highly active antiretroviral therapy (HAART). METHODS: A total of 1281 HIV-infected patients initiating HAART were enrolled in the AntiPROtease (APROCO) cohort. We investigated determinants of increase in CD4 count using longitudinal mixed models in patients who maintained a plasma HIV RNA <500 HIV-1 RNA copies/mL. RESULTS: A total of 870 patients had a virological response at month 4. The median follow-up time was 57 months. Mean estimated increases in CD4 count in patients with persistent virological response were 29.9 cells/muL/month before month 4, 6.4 cells/microL/month between months 4 and 36, and 0.7 cells/microL/month (not significantly different from 0) after month 36. Three factors were associated with a significantly positive CD4 count slope after month 36: male gender (+0.9), no history of antiretroviral therapy at baseline (+1.7) and baseline CD4 count <100 cells/microL (+2.6). In patients who maintained a virological response after 5 years of HAART, a CD4 count >500 cells/microL was achieved in 83% of those with a baseline CD4 count >or=200 cells/microL and in 45% of those with a baseline CD4 count <200 cells/microL. CONCLUSION: The increase in CD4 count reaches a plateau after 3 years of virological response. Even if patients initiating HAART with low CD4 counts still show a CD4 count increase after 3 years, it remains insufficient to overcome immune deficiency in all patients. 相似文献