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991.
Frozen (–18°C) de-seeded kiwifruit pulp (Actinidia deliciosa) was irradiated at a dose of 100 krad and stored at -18°C. Irradiation resulted in a 2.11 log10 reduction in aerobic plate count (APC) with bacteria being most susceptible. Molds were less susceptible than yeasts. Assessments carried out over 6 months storage showed no significant differences in physical, chemical and sensory properties between irradiated and nonirradiated pulps. The microbial populations of the pulps decreased in parallel throughout the storage period. Frozen storage without irradiation resulted in a 3 log10 reduction in APC over the 6 months period, a 38% reduction in ascorbic acid, and a slight loss of color. Three days frozen storage (– 18°C) following irradiation resulted in an APC only 0.89 log10 higher than 6 months frozen storage (- 18°C) without irradiation with potential savings in energy and holding times which could have economic benefits.  相似文献   
992.
Testing for syphilis during pregnancy reveals a positive serologic status in 0.02% of cases. However, a 66% rate of stillbirths is noted in women who are infected and who have not benefited from any treatment. Routine screening is at present performed during the early stages of pregnancy but a second serologic test during the third trimester is useful in the diagnosis of a late infection especially in drug users or HIV (human immunodeficiency virus) positive patients. Congenital syphilis is diagnosed in utero when a positive maternal serologic status is associated with ultrasound images showing fetal abnormalities; these include hepatosplenomegaly, hyperechogenic bowel, signs of bowel obstruction or fetal hydrops. Maternal syphilis is treated by delayed action penicillin and is indicated even for patients allergic to the antibiotic which in this particular case is delivered after desensitization. First line therapy by intravenous penicillin is indicated when confronted with the following high risk factors of congenital syphilis: an elevated titre of VDRL (venereal disease research laboratory) at the time of diagnosis or delivery, unknown date of the precise onset of the infection, the appearance of a rash or of a chancre during pregnancy, ultrasound fetal abnormalities or late therapy during the third trimester. Treatment of the new-born child will depend on the results of clinical, serologic and X-ray evaluation. Long term follow-up for at least a year is mandatory.  相似文献   
993.
994.
Casting properties of concentrated aqueous dispersions of zirconia stabilized by Y2O3, Si2O3, or a mixture of them are investigated. Optimum values of the pH, temperature, and slip concentration for the production of thin-walled vacuum-tight articles are established. Translated from Ogneupory, No. 3, pp. 12–15, March, 1995.  相似文献   
995.
The aim of our study was to show the results of the Magnetic Resonance Angiography of pelvis and lower extremities. 21 patients with clinical signs of venous thrombosis were examined. The obtained results show the MRA is very useful in evaluation of venous flow.  相似文献   
996.
We propose a sensor based on the temperature dependant behavior of the two lines of green emission of the erbium ion. The ratio of the intensities of these two lines presents a very low dependance on pump wavelength and pump power fluctuations. The sensitivity of the ratio is 0.013/°C between room temperature and 600°C. In addition, the measurement is self-calibrated  相似文献   
997.
The paper deals with the problem of improving co-ordination between the online economic dispatch (ED) function and the very short-term advance dispatch (AD). Both procedures are formulated as optimal dispatching problems, but while a static model is used for the ED function, a dynamic model is employed in AD. The need to account for ramp-rate limits of thermal power generation even in the ED phase is satisfied by adding suitable penalty terms to the objective function of the classical ED problem. These penalties are proportional to the Lagrange multipliers associated with ramp-rate limits that are active at the AD solution. An efficient updating procedure is used to correct the penalization by taking the load forecast errors into account. The proposed co-ordination procedure can provide the snapshot ED with the long range perspective of AD without resorting to heuristic approaches. The procedure is validated by extensive testing carried out both on a small CIGRE test case and on a medium-large scale network representative of the Italian EHV system. Moreover, test results show that the CPU time requirements of the modified ED procedure are still suited to online applications  相似文献   
998.
The MPC105 peripheral component interconnection bridge/memory controller provides a platform-specification-compliant bridge between Power PC microprocessors and the PCI bus. With it, designers can create systems using peripherals already designed for a variety of standard PC interfaces. This bridge chip also integrates a secondary cache controller and high-performance memory controller that supports DRAM or synchronous DRAM and ROM or flash ROM  相似文献   
999.
BACKGROUND: Data on cardiac and vascular structure in secondary hypertension are generally scarce, and no data on the interrelations between cardiac mass and structural characteristics of the vessel wall, both in large and in small resistance arteries, are presently available. OBJECTIVES: The aim of this study was to investigate the relation between structural changes in subcutaneous small arteries, left ventricular mass and wall thickness of the common carotid artery in patients with primary and secondary hypertension. METHODS: Seventy-four subjects were included in the study: 11 patients with pheochromocytoma, 14 with primary aldosteronism (PA), 19 with renovascular hypertension (RVH), 18 with essential hypertension (EH) and 12 normotensive (NT) control subjects. All subjects were submitted to a biopsy of subcutaneous fat. Morphologic characteristics of subcutaneous small resistance arteries (relaxed diameter <300 microm) were directly evaluated using a micromyographic technique. All subjects were submitted to calculation of left ventricular mass index (LVMI) and common carotid artery intima-media thickness (CCIMT), using ultrasound technique. RESULTS: The correlation coefficients between the media to lumen ratio in subcutaneous small arteries (M/L) and LVMI or between M/L and CCIMT were closer in RVH than in pheochromocytoma, EH or NT; in PA the correlation coefficients were slightly less close than those in RVH. An excess prevalence of carotid plaques in RVH was observed. CONCLUSIONS: A close relation between small resistance artery morphology and cardiac or carotid artery structure may be observed in those hypertensive patients in whom the renin-angiotensin-aldosterone system is activated. In constrast, in NT, EH and pheochromocytoma no significant correlation between M/L and LVMI or CCIMT was observed.  相似文献   
1000.
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