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71.
72.
After burn or resection of one submandibular salivary gland the contralateral gland responded by an increase of proliferation. The maximal mitotic index was observed 48 hours after the resection and 72 hours after the burn. Burn of the salivary gland initiated a stable, but weak compensatory hypertrophy of the contralateral gland. Hypertrophy of the gland was accompanied by an increase in the size of the cells and the nuclei whose area enlarged by 10 and 17%, respectively. Resection of the salivary gland caused an increase in the weight of the intact contralateral gland only at the early periods of the experiment. By the 30th and the 45th day after the operation the weight of the intact contralateral gland failed to differ from control. The detected differences in the compensatory growth of the intact glands in two types of action on the contralateral salivary gland depended on the quantity of the tissue degeneration products and on the period of their stay in the organism.  相似文献   
73.
The sintering behaviour of lanthanum chromite with the addition of 1 to 3 wt% TiO2 was studied. Densification was examined as a function of sintering temperature and TiO2 concentration. The results showed that pure LaCrO3 could not be densified to >75% of the theoretical density, while the densities exceeding 90% of the theoretical were achieved with 3 wt% titania addition at 1600° C. Metallographic study reveals a normal grain growth following the rate equationD 2D 0 2 =kt. Activation energies both for densification and grain growth have been estimated to be ≈ (80±5) k cal/mole in case of 3 wt% TiO2 addition.  相似文献   
74.
75.
Clinical course of multiple myeloma in patients under 40 years of age was analysed. In all cases diagnosis was established in III stage of the disease according to Durie and Salmon. In 4 cases good response to treatment (partial remission or stabilisation of proliferative process) was achieved. Survival time of 2 dead patients was 5 and 74 months, and that of 3 still alive patients is 41, 53, and 59 months and tends to be longer than median survival time of general population of patients with multiple myeloma.  相似文献   
76.
An approach to tackle protein-calorie malnutrition through domiciliary management is described. Children suffering from moderate and severe protein-calorie malnutrition were managed using a food supplement containing low cost locally available foodstuffs and nutrition education. An evaluation showed that the anthropometric improvement was closely associated with better concepts in nutrition and improved dietary practices following nutrition education. Parents of children suffering from kwashiorkor had better knowledge and practice compared with those of marasmus.  相似文献   
77.
The heat and mass transfer for unsteady laminar compressible boundary-layer flow, which is asymmetric with respect to a 3-dimensional stagnation point (i.e. for a jet incident at an angle on the body), have been studied. It is assumed that the free-stream velocity, wall temperature, and surface mass transfer vary arbitrarily with time and also that the gas has variable properties. The solution in the neighbourhood of the stagnation point has been obtained by series expansion in the longitudinal distance. The resulting partial differential equations have been solved numerically using an implicit finite-difference scheme. The results show that, in contrast with the symmetric flow, the maximum heat transfer does not occur at the stagnation point. The skin-friction and heat-transfer components due to asymmetric flow are only weakly affected by the mass transfer as compared to those components associated with symmetric flow. The variation of the wall temperature with time has a strong effect on the heat transfer component associated with the symmetric part of the flow. The skin friction and heat transfer are strongly affected by the variation of the density-viscosity product across the boundary layer. The skin friction responds more to the fluctuations of the free stream oscillating velocities than the heat transfer. The results have been compared with the available results and they are found to be in excellent agreement.  相似文献   
78.
Carbon-fiber reinforced (SiC + ZrC) mini-composites have been prepared via soft-solution process using inorganic precursors. In this process, water-soluble compounds have been used to act as precursor materials to impregnate the fiber tow. Thermal analysis provided the temperature range for the pyrolysis to convert the precursors into the desired (SiC + ZrC) matrix. X-ray diffraction of the composites confirmed the phase formation and the crystallite size of these phases were in the range of 25–40 nm. Cross-sectional microstructures of the composites have shown the matrix formation around each individual fiber. The mechanical properties revealed that the tensile strength and fracture energy of the composites pyrolyzed at 1600 °C were significantly higher with typical composite failure behavior, as compared to those pyrolyzed at 1700 °C. The statistical size effects of the tensile strength were investigated on the basis of the Weibull statistics.  相似文献   
79.
Zirconium oxide (ZrO2) nanostructures were synthesized by hydrothermal route. Surface morphology analysis depicts the formation of the nanobars and hexagonal-shaped nanodiscs at different synthesis conditions. The structural analysis confirms that the as-synthesized ZrO2 product is of pure monoclinic phase (m-ZrO2) with crystallite size of about 25 nm. The product consists of monodispersed nanoparticles of uniform composition, high purity, and crystallinity. The Raman spectra are quantitatively analyzed and the observed peaks are attributed to various vibration modes of the m-ZrO2. The UV–vis absorption spectrum showed a strong absorption peak at about 292 nm and the estimated optical band gap was around 3.57 eV. Photoluminescence (PL) spectrum of ZrO2 nanostructure showed a strong and broad emission peak at around 410 nm at room temperature, which can be attributed to the ionized oxygen vacancy in the material.  相似文献   
80.
Carbon nanotube–alumina (CNT–Al2O3) nanocomposites have been synthesized by direct growth of carbon nanotubes on alumina by chemical vapor deposition (CVD) and the as-grown nanocomposites were densified by spark plasma sintering (SPS). Surface morphology analysis shows that the CNTs and CNT bundles are very well distributed between the matrix grains creating a web of CNTs as a consequence of their in situ synthesis. Even after the SPS treatment, the CNTs in the composite material are still intact. Experimental result shows that the electrical conductivity of the composites increases with the CNT content and falls in the range of the conductivity of semiconductors. The nanocomposite with highest CNT content has electrical conductivity of 3336 S/m at near room temperature, which is about 13 orders of magnitude increase over that of pure alumina.  相似文献   
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