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71.
A.O. Lobo F.R. Marciano S.C. Ramos M.M. Machado E.J. Corat M.A.F. Corat 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1505-1511
We have analyzed the adhesion of mouse embryonic fibroblasts (MEFs) genetically modified by green fluorescence protein (GFP) gene cultured on vertically-aligned carbon nanotubes (VACNTs) after 6 days. The VACNTs films grown on Ti were obtained by microwave plasma chemical vapor deposition process using Fe catalyst and submitted to an oxygen plasma treatment, for 2 min, at 400 V and 80 mTorr, to convert them to superhydrophilic. Cellular adhesion and morphology were analyzed by scanning electron, fluorescence microscopy, and thermodynamics analysis. Characterizations of superhydrophilic VACNTs films were evaluated by contact angle and X-Ray Photoelectron Spectroscopy. Differences of crowd adhered cells, as well as their spreading on superhydrophilic VACNTs scaffolds, were evaluated using focal adhesion analysis. This study was the first to demonstrate, in real time, that the wettability of VACNTs scaffolds might have enhanced and differential adherence patterns to the MEF-GFP on VACNTs substrates. 相似文献
72.
A. Ya. Polishchuk A. J. M. Valente G. Camino M. P. Luda N. N. Madyuskin V. M. M. Lobo G. E. Zaikov M. Revellino 《应用聚合物科学杂志》2002,83(5):1157-1166
Engineering materials containing poly(vinyl acetate) (PVAc) as the key component undergo hydrolytic degradation, which must be minimized or, at least, controlled. To characterize PVAc hydrolysis quantitatively, the diffusion of acetic acid (HAc) in PVAc, poly(vinyl alcohol) (PVA), unsaturated polyester (UPE), and a UPE/PVAc blend was studied in detail. The permeability cell earlier developed by the authors was modified here to reduce experimental error. As the diffusion and solubility coefficients of water and HAc in the above materials were measured at different temperatures, a mathematical model was developed, which takes proper account of the combined water and HAc diffusion in PVAc undergoing partial hydrolysis. The model was further validated by the experimental data obtained at 70°C for UPE/PVAc film, simulating a matrix of sheet‐molding compounds composite materials. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1157–1166, 2002 相似文献
73.
74.
JR Green JA Gibson GD Kerr ET Swarbrick AJ Lobo CD Holdsworth JP Crowe KJ Schofield MD Taylor 《Canadian Metallurgical Quarterly》1998,12(12):1207-1216
BACKGROUND: Despite widespread use of aminosalicylates as maintenance treatment for ulcerative colitis (UC), patients still report troublesome symptoms, often nocturnally. AIM: To compare the efficacy and safety of balsalazide (Colazide) with mesalazine (Asacol) in maintaining UC remission. METHODS: A randomized, double-blind comparison of balsalazide 3 g daily (1.04 g 5-ASA) and mesalazine 1.2 g daily for 12 months, in 99 (95 evaluable) patients in UC remission. RESULTS: Balsalazide patients experienced more asymptomatic nights (90% vs. 77%, P=0.0011) and days (58% vs. 50%, N.S.) during the first 3 months. Balsalazide patients experienced more symptom-free nights per week (6.4+/-1.7 vs. 4.7+/-2.8; P=0.0006) and fewer nights per week with blood on their stools or on the toilet paper, mucus with their stools or with sleep disturbance resulting from symptoms or lavatory visits (each P < 0.05). Fewer balsalazide patients relapsed within 3 months (10% vs. 28%; P=0.0354). Remission at 12 months was 58%, in both groups. Similar proportions of patients reported adverse events (61% balsalazide vs. 65% mesalazine). There were five serious adverse events (two balsalazide, three mesalazine) and four withdrawals due to unacceptable adverse events (three balsalazide, one mesalazine), of which one in each group was also a serious adverse event. CONCLUSIONS: Balsalazide 3 g/day and mesalazine 1.2 g/ day effectively maintain UC remission and are equally well tolerated over 12 months. At this dose balsalazide prevents more relapses during the first 3 months of treatment and controls nocturnal symptoms more effectively. 相似文献
75.
A García Enguídanos E Crespo Azanza J Díaz Recaséns F Lobo Samper JA Jorge Herrero R Sáinz de la Cuesta Abbad 《Canadian Metallurgical Quarterly》1998,198(8):502-505
OBJECTIVE: To determine the usefulness of diagnostic tests performed before a second look laparotomy in patients with epithelial ovarian cancer. STUDY DESIGN: Thirty-three patients with epithelial ovarian cancer attended at Fundación Jiménez Díaz from 1984 to 1995 were studied. All patients initially underwent cyto-reducing surgery, followed by at least six platinum-based chemotherapy cycles. Prior to second look laparotomy all patients were evaluated by computerized tomography (CT) of the pelvis and abdomen, CA-125, pelvic-abdominal echography and gynecologic examination. To evaluate sensitivity, specificity, positive predictive value and negative predictive value for each test contingency tables were used. RESULTS: Eleven out of the 33 second look patients (33%) had histologic or cytologic evidence of disease. Six out of the eleven positive second look had a positive CT prior to second look (sensitivity of 55%). CT showed lack of disease in 21 out of the 22 negative second look cases (specificity 95%). Positive and negative predictive values of the test were 86% and 81%, respectively. Nine cases out of the 28 who had a CA-125 obtained had a positive second look. Four out of these nine patients had an increased CA-125 value (sensitivity 44%, specificity 95%, positive predictive value 80% and negative predictive value 78%). Sensitivity, specificity, positive predictive value and negative predictive value of physical examination and echography were 36%, 100%, 100%, 76% and 27%, 95%, 75%, 72%, respectively. On the other hand, sensitivity, specificity, positive predictive value and negative predictive value of all tests taken together were 64%, 91%, 78% and 83%, with a rate of false-negative results of 17% and a rate of false-positive results of 22%. CONCLUSION: Pelvic-abdominal computerized tomography, CA-125, pelvic-abdominal echography and gynecologic examination can be an alternative to second look laparotomy for the diagnosis of persistence or recurrence of the disease in patients with epithelial ovarian cancer. 相似文献
76.
Inertial sensors attached to a camera can provide valuable data about camera pose and movement. In biological vision systems, inertial cues provided by the vestibular system are fused with vision at an early processing stage. In this article we set a framework for the combination of these two sensing modalities. Cameras can be seen as ray direction measuring devices, and in the case of stereo vision, depth along the ray can also be computed. The ego‐motion can be sensed by the inertial sensors, but there are limitations determined by the sensor noise level. Keeping track of the vertical direction is required, so that gravity acceleration can be compensated for, and provides a valuable spatial reference. Results are shown of stereo depth map alignment using the vertical reference. The depth map points are mapped to a vertically aligned world frame of reference. In order to detect the ground plane, a histogram is performed for the different heights. Taking the ground plane as a reference plane for the acquired maps, the fusion of multiple maps reduces to a 2D translation and rotation problem. The dynamic inertial cues can be used as a first approximation for this transformation, allowing a fast depth map registration method. They also provide an image independent location of the image focus of expansion and center of rotation useful during visual based navigation tasks. © 2004 Wiley Periodicals, Inc. 相似文献
77.
RD Hull GE Raskob RF Brant GF Pineo KA Valentine 《Canadian Metallurgical Quarterly》1997,157(22):2562-2568
BACKGROUND: Randomized trials have demonstrated the importance of achieving adequate heparinization early in the course of therapy. Recently, some authors reported a pooled analysis of selected studies in the literature that suggested that there is no convincing evidence that the risk of recurrent venous thromboembolism is critically dependent on achieving a therapeutic activated partial thromboplastin time result at 24 to 48 hours. METHODS: We provide the analyses of patient groups entered into our series of 3 consecutive double-blind randomized trials evaluating initial heparin therapy for proximal deep venous thrombosis. RESULTS: Logistic regression analysis of the patient groups receiving the less intense initial intravenous heparin dose of 30,000 U/24 h demonstrated that subtherapy for 24 hours predicted the onset of venous thromboembolic events. Failure to achieve a therapeutic activated partial thromboplastin time by 24 hours was associated with a 23.3% frequency of venous thromboembolism vs 4% to 6% for those whose activated partial thromboplastin time exceeded the therapeutic threshold by 24 hours (P=.02). Time-to-event analysis shows the increased frequency of recurrent venous thromboembolic events during the period of study in patients who were subtherapeutic for 24 hours compared with those who were therapeutic (P=.001). CONCLUSIONS: Our findings reaffirm the clinical importance of rapidly achieving therapeutic levels of heparin. Patients who failed to achieve the therapeutic threshold by 24 hours were at an increased risk of subsequent recurrent venous thromboembolism. These findings are independently supported by the results of a randomized trial comparing different intensities of initial heparin treatment by continuous infusion. 相似文献
78.
Ss aged 54–84 yrs performed 5 separate tasks involving various aspects of face processing: (1) structural decisions, (2) familiarity decisions, (3) semantic decisions, (4) 1st-name decisions, and (5) name retrieval. For the categorization tasks (1–4), the mean reaction times (RTs) for the older Ss (over 65) were plotted against the corresponding means for the younger Ss (under 65). This produced a linear function (slope >1, intercept 相似文献
79.
WH Cheng YS Ho BA Valentine DA Ross GF Combs XG Lei 《Canadian Metallurgical Quarterly》1998,128(7):1070-1076
A case-control study was conducted between 1992 and 1996 in six Italian areas. It included 537 women with colon cancer, 291 women with rectal cancer and 2081 control women in hospital for acute conditions, unrelated to hormonal or gynaecological diseases. A higher age at menopause was associated with increased colon cancer risk (odds ratio (OR) for > or = 53 years compared with < 50 years = 1.39, 95% confidence interval (CI) 1.04-1.87). Among parous women, a significant trend of decreasing colon cancer risk with increasing number of births was seen for colon (OR for > or = 4 births compared with 1 birth = 0.62, 95% CI 0.42-0.90), but not for rectal cancer. Nulliparous women, however, were at lower risk than women with a single birth, and age at first birth was directly associated with risk. While oral contraceptive use showed no significant influence, ever users of hormone replacement therapy had a reduced risk of rectal cancer (OR = 0.56, 95% CI 0.31-1.01). Thus, the association of colorectal cancer with reproductive and menstrual factors is neither strong nor consistent. 相似文献
80.
Healthy hair samples from golden hamsters were examined for the presence of dermatophytes and non-dermatophytes using baiting technique and direct inoculation. Thirty-four species and 2 varieties attributed to 17 genera were recovered. Paecilomyces variotii (isolated from 84.4% of the examined hair) and Aspergillus niger (81.3%) were the more frequent isolates on Sabouraud's dextrose agar (SDA) without cycloheximide. Our results have clearly demonstrated that the hair of hamster was free from true dermatophytes. Using the dilution plate method many fungal species were isolated from cage material (7 genera and 10 species + 1 variety); from faeces (10 genera and 17 species); from standard chow (3 genera and 6 species) of hamster. P. variotii which was the most frequent fungus in the preceding 3 substrates was completely absent in the presence of cycloheximide in SDA. The present study has demonstrated for the first time the isolation of Trichophyton rubrum from hamster faeces. Also, several saprophytic and cycloheximide resistant fungi were isolated. In the air of hamster cage Cladosporium cladosporioides, Penicillium chrysogenum, Alternaria alternata and Scopulariopsis brevicaulis were the most dominant species on SDA with or without cycloheximide. Using the agar diffusion method, Aloe sap, onion oil, garlic bulb extract and aqueous leaf extracts of Andropogon citratus, Euphorbia sp. and Ruta graveolens were tested for their antifungal activity on 10 fungal species. It was observed that onion oil exhibited a high inhibitory effect against most of the tested fungi. 相似文献