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31.
MD Cohen ST Auringer JL Grosfeld CA Galliani NA Heerema 《Canadian Metallurgical Quarterly》1993,23(6):463-466
The purpose of this study is to present three patients with multifocal primary neuroblastoma, to review the literature, and describe the radiographic findings. SUBJECTS AND METHODS: Three children with multifocal neuroblastoma have been identified. The case histories and imaging findings in these patients are reviewed. RESULTS: Two children had synchronous and one child had metachronous multifocal primary neuroblastoma. The primary tumors were both in the abdomen in one patient, both in the chest in another patient, and in the chest and abdomen in the third patient. Evidence for multifocal origin of these tumors, rather than metastatic spread, is presented. CONCLUSION: Multifocal primary neuroblastomas can occur. The tumors maybe synchronous or metachronous. Awareness of this disorder may prevent errors in diagnosis and staging. Although not identified in our patients there is a strong familial incidence of neuroblastomas in those patients with multifocal tumors. 相似文献
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Pulmonary surfactant is a complex mixture of lipids and proteins that functions to keep alveoli from collapsing at the end of expiration. Dipalmitoylphosphatidylcholine has been identified as the most important component for lowering surface tension at the air-liquid interface. Hydrophobic surfactant apoproteins, SP-B and SP-C, play essential roles in the biophysical functions of the surfactant phospholipids. Hydrophilic surfactant apoproteins (SP-A and SP-D) that are members of C-type lectin superfamily, interact with phospholipids and glycolipids and modulate host defense functions in the lung. SP-A also plays an important role in regulating phospholipid homeostasis in the alveolar spaces. Recent advances in genetics and molecular biology have clarified the structure-function relationship of surfactant apoproteins. 相似文献
34.
Kaolinite samples treated with uniaxial pressures higher than 0.1 GPa or grinding times greater than 0.3 h show changes in their crystallinity. These changes are easily detected by the X-ray diffraction (XRD) technique and can be quantified from Hinckley (HI), Lietard (R2) and also reference intensity ratio (RIR) index studies. The sensitivity of these indices to the Crystallinity changes is; HI>RIR>R2. In the range of pressures and grinding times considered, these values can be diminished by 50%. The variations in these indices with either the pressure or grinding time follow logarithmic laws whose correlation coefficients are closed to unity. Infrared (IR) spectroscopy and thermal analysis studies show low sensitivity to the changes introduced by grinding or pressure. Nevertheless, thermal gravimetric curves confirm the decrease in the dehydroxylation starting point of about 100°C for the pressed and ground samples. Transmission electron microscopy (TEM) reveals important changes in kaolinite particle morphologies after pressure and grinding treatments. The samples compressed at 0.1, 0.32, 0.85, 1.0 and 2.0 GPa show a large number of defects (fractures, bending, deformations and rolling of layers, glide and rotation of the shell). The ground samples show grain boundaries, dislocations, twins and rounded voids. These defects are responsible for the decrease in crystallinity of the kaolinite samples shown in the XRD and IR studies. 相似文献
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María Pinto Dora Sales Anne-Vinciane Doucet Andrés Fernández-Ramos David Guerrero 《Scientometrics》2007,72(2):345-370
The purpose of the study proposed in this paper is to evaluate the Spanish public university websites dedicated to the European
Higher Education Area (EHEA). To do so, the quality of these resources has been analysed in the light of data provided by
a series of indicators grouped in seven criteria, most of which were used to determine what information is made available
and in what way. The criteria used in our analysis are: visibility, authority, updatedness, accesibility, correctness and
completeness, quality assessment and navigability.
All in all, the results allow us to carry out an overall diagnosis of the situation and also provide us with information about
the situation at each university, thus revealing their main strengths, namely authority and navegability, and also their chief
shortcomings: updatedness, accessibility and quality assessment. In this way it is possible to detect the best practices in
each of the aspects evaluated so that they can serve as an example and guide for universities with greater deficiencies and
thus help them to improve their EHEA websites. 相似文献
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The activity of rifabutin (LM 427) against Mycobacterium leprae was evaluated in armadillos inoculated earlier with human-derived M. leprae. Rifabutin was administered daily at a dose of 6 mg/kg body weight/day. The effect of rifabutin on M. leprae harvested from armadillos was determined by measuring the intracellular levels of ATP (an indicator of metabolic activity) of M. leprae and also their ability to multiply in the mouse footpads and in vitro in DH medium. Within 2 weeks of initiating the treatment, ATP levels declined to 21% of the original (pre-treatment level) and these M. leprae failed to multiply in the footpads of mice as well as in the in vitro culture system. This suggests that rifabutin was able to kill all M. leprae within 2 weeks. After 8 weeks the treatment was terminated and results showed that M. leprae from the treated armadillos remained non-viable in the mouse footpad system as well as in the in vitro system, indicating bactericidal action of rifabutin. The results suggest that rifabutin can be a substitute for rifampin in the leprosy multi-drug therapy regimen. 相似文献