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41.
42.
In this study we compare processing times and platelet yields of eight systems: five double-needle (DN)--Fenwal CS3000 Plus with interface offset (IO) of 6 (Fen 6) and IO of 10 (Fen 10), a prototype Fenwal Amicus (AM-DN), Spectra version 4 (Spec 4-DN) and version 5 with leukoreduction system (Spec 5-LRS); and three single-needle (SN) systems--Haemonetics MCS Plus (MCS+), prototype Amicus (AM-SN), and Spectra version 4 (Spec 4-SN). Twenty-five procedures from each of the systems (except AM-SN, N = 13) were compared; each system had comparable preprocedure platelet counts and similar endpoints. Five systems--MCS+, Fen 6, Fen 10 with leukoreduction filter (MCS + LRF), (Fen 6 LRF), (Fen 10 LRF), as well as AM-DN, and Spec 5-LRS--were compared for WBC content. P-selectin expression was compared in the MCS+; Fen-10 with A-35 (Fen 10-A35) and PLT-30 (Fen 10-PLT30) collection chambers; Spec 4-DN; and platelet-rich plasma. We found AM-DN (63 +/- 16 min) had a significantly lower average processing time than all other systems except AM-SN. Spectra 4-DN (5.6 +/- 1.7 x 10(11) Plt) produced significantly more platelets and had a significantly higher incidence of products > or = 6.0 x 10(11) (56%) and higher incidence of products > or = 6.6 x 10(11) Plt (32%) than all other systems. AM-DN (0.073 +/- 0.017 x 10(11) Plt/min) had a significantly higher collection rate than all other systems except AM-SN. The WBC content comparison indicated MCS+ with a filter; and AM-DN and Spectra 5-LRS without filters were capable of consistently (99.32-100%) producing products with < 5 x 10(6) WBC, but were less consistent (86.36-99.26%) at < 1 x 10(6) WBC. MCS+ and Fen 10-PLT30 had significantly (p < .05) less p-selectin expression than all other systems but not between each other. From the data in this study, if leukoreduced platelets were needed in the shortest processing time, the first and second choices would be Amicus-DN and Spectra 5-LRS, respectively.  相似文献   
43.
BACKGROUND: In recent years there has been a change in the opportunistic diseases incidence in HIV-infected patients. The change could be related to the use antiviral therapy and chemoprophylaxis strategies. The aim of the present study was to evaluate if medical intervention is able to modificate the clinical presentation of AIDS and the CD4+ lymphocyte counts at time of AIDS diagnosis. PATIENTS AND METHODS: The first AIDS-defining condition and the CD4+ count at time of AIDS diagnosis were analyzed in 95 HIV-infected patients who developed an AIDS-defining disease since April 1989 until March 1996, retrospectively reviewed. Patients who had been previously followed at an AIDS Unit were compared with those who had not. RESULTS: The frequency of Pneumocystis carinii pneumonia as the first AIDS-defining condition was lower in medically followed patients. Among this group, AIDS cases who received chemoprophylaxis with isoniazide showed a decrease in the rate of tuberculosis. No differences were found in CD4+ lymphocyte counts between both groups. CONCLUSIONS: As a result of medical intervention significant changes have occurred in the spectrum of initial AIDS-defining conditions in relation to medical intervention; a decrease in the frequency of Pneumocystis carinii pneumonia and tuberculosis have been found; however, the CD4+ lymphocyte counts at time of AIDS diagnosis are not modificated by medical intervention.  相似文献   
44.
In this work we propose a criterion to apply the Abel inversion in the case of a small set of experimental data to be used in laboratory plasmas. The Nestor-Olsen method, spline interpolation, and Fourier transform Abel inversion have been compared in order to study the influence of statistical noise and the number of sampled data. The application of this criterion permits us to obtain a radial distribution of the plasma parameters (densities and temperatures) from the spectral line profiles emitted by the discharge. The proposed criterion has been tested using the lateral intensities of several lines emitted by a microwave helium plasma column generated at atmospheric pressure.  相似文献   
45.
OBJECTIVE: Three-dimensional models created by milling machines and stereolithography on the basis of 3-dimensional computed tomography scans have become essential in the diagnosis and therapy planning of oral and maxillofacial disorders. The purpose of this study, based on 3 clinical cases, was to examine the advantages of using 3-dimensional computed tomography scans and 3-dimensional milling models of the maxillary sinus before operative sinus elevation and of developing an operative layout with the aid of 3-dimensional models. REPORT DESIGN: Three patients with atrophy of the maxillary alveolar ridge received computed tomography scans before operative sinus elevation with iliac bone transplants and simultaneous dental implantation. These computed tomography data were used to create 3-dimensional graphic and plastic reconstructions of the maxillary sinuses. RESULTS: The 3-dimensional milling models enabled the development of an exact preoperative layout that took into consideration the exact shape of the iliac bone and the selection of dental screw implants. Furthermore, the models offered the possibility of producing an acrylic device for precise implant insertion. Precise planning resulted in good success with implantation 2 years after surgery. CONCLUSION: Three-dimensional diagnosis and treatment layout have become an acknowledge method of operative maxillary sinus floor augmentation combined with simultaneous dental implantation in the upper jaw in difficult cases of sinus lift operations. As far as transplant shape and sinus anatomy are concerned, this has resulted in greater intraoperative precision. A 1-step procedure can thus be performed for augmentation and implantation through use of a well-adapted block transplant and dental screw implants in patients with extensive alveolar ridge atrophy.  相似文献   
46.
The Ni hyperaccumulator, plant species Senecio coronatus (Thunb.) Harv., Asteraceae is an example of plant adaptation mechanisms to different ecological conditions. This widespread species can inter alia be found on serpentine outcrops and the genotypes growing in serpentine soils show different ways of adaptation. The populations from two distant localities take up and translocate Ni in concentrations which are normally phytotoxic, while plants growing on a different site, in the vicinity of another hyperaccumulating species, absorb amounts which are typical for most of the plants found on serpentine soils. The NAC nuclear microprobe was used to compare the distribution of Ni and other elements in selected organs and cells with simultaneous use of PIXE and proton BackScattering (BS). Quantitative maps of stems showed large differences in concentrations and distributions of major and trace elements. In hyperaccumulating genotypes Ni is present everywhere within stem tissues, but the highest concentrations were found in the epidermis, cortex and phloem. In non-accumulating plants Ni was concentrated in the phloem. In the leaf epidermis Ni was concentrated in the cell walls for both accumulating and non-accumulating plants. These results suggest that biochemical diversity is more than morphological, because investigated genotypes belong to the same taxon.  相似文献   
47.
48.
Biallelic germline mismatch repair (MMR) gene (MLH1, MSH2, MSH6, and PMS2) mutations are an extremely rare event that causes constitutional mismatch repair deficiency (CMMRD) syndrome. CMMRD is underdiagnosed and often debuts with pediatric malignant brain tumors. A high degree of clinical awareness of the CMMRD phenotype is needed to identify new cases. Immunohistochemical (IHC) assessment of MMR protein expression and analysis of microsatellite instability (MSI) are the first tools with which to initiate the study of this syndrome in solid malignancies. MMR IHC shows a hallmark pattern with absence of staining in both neoplastic and non-neoplastic cells for the biallelic mutated gene. However, MSI often fails in brain malignancies. The aim of this report is to draw attention to the peculiar IHC profile that characterizes CMMRD syndrome and to review the difficulties in reaching an accurate diagnosis by describing the case of two siblings with biallelic MSH6 germline mutations and brain tumors. Given the difficulties involved in early diagnosis of CMMRD we propose the use of the IHC of MMR proteins in all malignant brain tumors diagnosed in individuals younger than 25 years-old to facilitate the diagnosis of CMMRD and to select those neoplasms that will benefit from immunotherapy treatment.  相似文献   
49.
Aqueous solutions of vesicle-forming lipids mixed with micelle-forming copolymers may result in stabilized and biocompatible aggregates. Differential scanning calorimetry (DSC) and dynamic light scattering (DLS) techniques were used here to investigate the effects of the nonionic triblock copolymer Pluronic F127 (F127) on the thermal behavior, structural changes, and hydrodynamic size of cationic vesicles from dioctadecyldimethylammonium chloride (DODAC), dioctadecyldimethylammonium bromide (DODAB), and didodecyldimethylammonium bromide (DDAB) in aqueous dispersion. The DSC thermograms indicate that upon the addition of up to 5.0 mM F127, a vesicle-to-micelle transition occurs in three stages. First, there is a predominance of lipid-F127 mixed vesicles, followed by the co-existence of mixed vesicles and micelles, and finally, the system is dominated by mixed micelles. DLS results reveal that with the addition of F127 to the lipid dispersions, the size of the assembled structures tends to decrease, also indicating structural changes of vesicles to micelles. These results indicate that the borders between these stages depend on the lipid chain length and counterion type.  相似文献   
50.
Fractal development during polymerization of a dimethacrylate system (Bis‐GMA/TEGDMA) has been studied through the analysis of time series obtained sequentially by pulsed photoacoustics. The photoacoustic signals as obtained in situ during photopolymerization of Bis‐GMA/TEDGMA were analyzed by rescaled range analysis, dispersion analysis, and detrended fluctuation analysis methods. The analysis reveals the presence of more than one scaling parameter and, therefore, belongs to a complex process known as multifractal. The evolution of fractality during photopolymerization was compared under equivalent conditions with the chemical conversion (of dimethacrylate double bonds) as a function of time, as monitor by infrared spectroscopy. This kinetic study was also used to correlate the fractal nature of the dimethacrylate reaction system with the condensed‐state transitions emerging during the photochemical reaction. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
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