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61.
OBJECTIVE: To review the cytomorphologic picture of pituitary adenomas as revealed by intraoperative smear preparation and to note features useful in differential diagnosis from other sellar tumors. STUDY DESIGN: A total of 46 pituitary adenomas in which intraoperative smears were available were reviewed. All tumors were subsequently examined by paraffin section and immunohistochemistry. RESULTS: The important cytologic appearances were epithelial cords and sheets with dyscohesive ends, acini and papillary formations. Cytoplasmic contents, depending on functional status, were variably clear, with vacuolation or eosinophilic bodies and occasional paranuclear bodies. Mild cellular pleomorphism and binucleate forms were common. CONCLUSIONS: Pituitary adenomas possess distinct cytologic features that are important in intraoperative differential diagnoses from normal pituitary tissues, germinomas, meningiomas, craniopharyngiomas and oligodendrogliomas.  相似文献   
62.
Optimization of Nannochloropsis oculata growth was undertaken using the response surface method. A central composite design was defined to study the effects of temperature, pH, incident light intensity and aeration rate on the maximum growth rate of the microalga. Using statistical analysis, the first model calculated to fit results was twice improved. The final model obtained was used to clarify the effects of each factor and their interactions on the growth of Nannochloropsis oculata. The optimum growth conditions of this microorganism were also estimated as 21 °C, 52 µmol photons m?2 s?1, pH 8.4 and 14.7 VVH of aeration rate. These conditions were tested and validated experimentally since the maximum growth rate achieved with these parameters, 0.0359 h?1, is the best reported in this study. Copyright © 2006 Society of Chemical Industry  相似文献   
63.
The inverted gamma distribution is studied as a prospective life distribution. The maximum likelihood estimation of the parameters of the inverted gamma is discussed, together with the estimation of the corresponding reliability function. A comparison with the log-normal and inverse Gaussian distribution is illustrated in terms of an example based on a maintenance data set.  相似文献   
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BACKGROUND: The Chiquitano tribe lives in the southern Amazonas region in Bolivia, remote from larger towns. Data on the epidemiology of neurological disorders are completely lacking. METHODS: A combined prospective-retrospective study was designed to determine the prevalence and annual incidence of major neurological diseases. In an one-year prospective study 1514 individuals (total population 5652) who consulted the general practitioner were interviewed and examined for neurological disturbances. These histories were analysed retrospectively by a neurologist and classified according the diagnosis key of the DGN. RESULTS: During a one-year period (April 1995-March 1996), 139 patients suffering from neurological diseases were seen (one-year incidence and prevalence 2.45%). Cervical and lumbosacral pain syndromes were the most common neurological problems; these were caused by sleeping in hammocks, and by hard agricultural labour. Tropical myositis (12.9%) was very frequent and the most frequent muscle disease. Epilepsy was found in 11 patients and extrapyramidal syndromes in 2 patients. Regarding epilepsy, a high dark rate is assumed because of social and cultural traditions. Strokes are rare, since many risk factors are not present. All cases of meningitis were lethal and clearly demonstrated infrastructural problems. Patients with social diseases (AIDS, drug- and alcohol addiction, injuries caused by violence) were rarely seen. CONCLUSION: In a shrinking world, and with the development of "Tropical Neurology" as a specialised discipline neuroepidemiological data are increasingly important for two reasons. First of all, they sensitise neurologists to this topic, and secondly, they can be used to estimate the need for neurologists serving the Third World's minority populations.  相似文献   
66.
Mullite/glass/nano aluminum nitride (AlN) filler (1–10 wt% AlN) composites were successfully fabricated for the low-temperature co-fired ceramics applications that require densification temperatures lower than 950°C, high thermal conductivity to dissipate heat and thermal expansion coefficient matched to Si for reliability, and low dielectric constant for high signal transmission speed. Densification temperatures were ≤825°C for all composites due to the viscous sintering of the glass matrix. X-ray diffraction proved that AlN neither chemically reacted with other phases nor decomposed with temperature. The number of closed pores increased with the AlN content, which limited the property improvement expected. A dense mullite/glass/AlN (10 wt%) composite had a thermal expansion coefficient of 4.44 ppm/°C between 25 and 300°C, thermal conductivity of 1.76 W/m.K at 25°C, dielectric constant (loss) of 6.42 (0.0017) at 5 MHz, flexural strength of 88 MPa and elastic modulus of 82 GPa, that are comparable to the commercial low temperature co-fired ceramics products.  相似文献   
67.
Acrylamide (AAm)/acrylic acid (AAc) hydrogels in the cylindirical form were prepared by γ‐irradiating binary systems of AAm/AAc with 2.6–20.0 kGy γ‐rays. The effect of the dose and relative amounts of AAc and pH on the swelling properties, diffusion behavior of water, diffusion coefficients, and network properties of hydrogel systems was investigated. The swelling capacities of AAm/AAc hydrogels were in the range of 1000–3000%, while poly(acrylamide) (PAAm) hydrogels swelled in the range of 450–700%. Water diffusion into hydrogels was found to be non‐Fickian‐type diffusion. Diffusion coefficients of AAm/AAc hydrogels were found between 0.79 × 10?5 and 2.78 × 10?5 cm2 min?1. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3570–3580, 2002  相似文献   
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A CFD-based model for predicting the performance of annular reactors with surface reaction was developed. The capability of several hydrodynamic models to predict successfully the kinetic behavior of the reactor under diffusion limiting conditions was assessed against experimental data. The evaluation included five models: laminar, standard kε, realizable kε, Reynolds stress (RSM), and Abe–Kondoh–Nagano (AKN). The catalytic decomposition of hydrogen peroxide over a Mn/Al oxide catalyst coated on the reactor surface was used as a model reaction. The reactor was tested within a range of flow rates corresponding to 530<Re<11,000 and intrinsic reaction rate constants of 5×10?5 to 1 m/s. The results demonstrated that the performance of the hydrodynamic models is associated with their capability to predict external mass transfer and ultimately, the level of mass transfer limitation present in the reacting system. For laminar flow conditions, the laminar model is capable of predicting the experimental behavior of the system. For transient and turbulent flow regimes, all the analyzed turbulence models provided good predictions of the system when the process was controlled by surface reaction. When the system presented some degree of mass transfer limitation, AKN and RSM exhibited better performance.  相似文献   
70.
In fish, fasting leads to loss of muscle mass. This condition triggers oxidative stress, and therefore, antioxidants can be an alternative to muscle recovery. We investigated the effects of antioxidant ascorbic acid (AA) on the morphology, antioxidant enzyme activity, and gene expression in the skeletal muscle of pacu (Piaractus mesopotamicus) following fasting, using in vitro and in vivo strategies. Isolated muscle cells of the pacu were subjected to 72 h of nutrient restriction, followed by 24 h of incubation with nutrients or nutrients and AA (200 µM). Fish were fasted for 15 days, followed by 6 h and 15 and 30 days of refeeding with 100, 200, and 400 mg/kg of AA supplementation. AA addition increased cell diameter and the expression of anabolic and cell proliferation genes in vitro. In vivo, 400 mg/kg of AA increased anabolic and proliferative genes expression at 6 h of refeeding, the fiber diameter and the expression of genes related to cell proliferation at 15 days, and the expression of catabolic and oxidative metabolism genes at 30 days. Catalase activity remained low in the higher supplementation group. In conclusion, AA directly affected the isolated muscle cells, and the higher AA supplementation positively influenced muscle growth after fasting.  相似文献   
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