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排序方式: 共有1240条查询结果,搜索用时 15 毫秒
1.
NC Moore 《Canadian Metallurgical Quarterly》1997,86(2):81-82
The nation's health care system is undergoing a period of rapid change that will profoundly affect women's health care services and, ultimately, women's health. Although managed care is quickly becoming the predominant mode of health care delivery in the United States, a new, more consumer-focused, and accountable model known as organized systems of care (OSC) is emerging. OSC development has been driven by large private and public employers seeking to purchase the highest quality health care for the best price. The changes in health care delivery encouraged by these innovative employers will provide women with optimal care and attention, which will in turn help them attract and retain a competitive and productive workforce. 相似文献
2.
A longitudinal study to estimate the serum calcium, phosphate and alkaline phosphatase levels of 89 ambulatory epileptic children, aged between 3 years and 12 years, and having generalised tonic-clonic seizures, was carried out. None was on any form of medication for the treatment of seizures prior to presentation. Each patient received only phenobarbitone during the period of study. Serum levels of the biochemical parameters were determined at presentation, 6 months and 12 months, while serum phenobarbitone levels were estimated at 6 months and 12 months. Mean serum calcium, phosphate and alkaline phosphatase of the patients remained within the normal range. Using the paired 't' test, the differences in the levels of the parameters at the three measurements were not statistically significant (P > 0.05). Serum phenobarbitone levels remained within the therapeutic range during the period of study. Our results show that over a 12-month period, serum levels of calcium, phosphate, and alkaline phosphatase, remain normal in ambulant epileptic children treated with phenobarbitone. 相似文献
3.
Cypriano G da Trindade Neto Ana LP Fernandes Ana IB Santos Waldenice A Morais Marcos VM Navarro Tereza NC Dantas Mrcia R Pereira Jos LC Fonseca 《Polymer International》2005,54(4):659-666
Complexation of chitosan in aqueous solutions by low molecular weight electrolytes is one of the simplest methods for the preparation of aqueous chitosan dispersions. In this work, the influence of storage time, sulfate concentration, method of preparation and surfactant content on some properties of the resultant chitosan dispersions (turbidity, viscosity and zeta potential) was analyzed. Turbidimetry was adequate to monitor the formation of particles, while viscometry was suitable to monitor changes in the dispersing phase. An analysis of the properties of these systems, mainly in terms of particle–particle and macromolecule–macromolecule interactions was carried out. Copyright © 2004 Society of Chemical Industry 相似文献
4.
J. M. Richards M. I. Darby R. Baggott G. H. Wosteim Holm B. Yates G. Dorey L. N. Phillips 《Journal of Materials Science》1989,24(2):584-589
The effects of defects on the mechanical properties of carbon fibre reinforced polyethersulphone laminates have been measured. The defects studied were cut fibre plies, omission of polymer films and local delamination produced by the inclusion of foreign matter. Of these it was found that only cut plies had a significant detrimental effect on the strength of a laminate. For specimens with two cut plies, the failure stress, tensile, flexural and compressive in the remaining continuous plies was the same as in the defect-free material, provided that the cut plies were widely separated. However the failure stresses were 15–18% lower in the continuous plies in the specimens containing two cut plies which were more closely spaced and in specimens containing four cut plies. 相似文献
5.
1. Supramedullary structures including the ventral medial prefrontal cortex (MPFC) and the midbrain cuneiform nucleus (CnF) project directly and indirectly to premotor sympatho-excitatory neurons of the rostral ventrolateral medulla (RVLM) that are critically involved in the generation of sympathetic vasomotor tone. 2. Electrophysiological studies have demonstrated that activation of depressor sites within the MPFC is associated with splanchnic sympathetic vasomotor inhibition and inhibition of the activity of RVLM sympathoexcitatory neurons. 3. Antidromic mapping and anatomical studies support the notion that a relay in the nucleus tractus solitarius is involved in the cardiovascular response to MPFC stimulation. 4. The midbrain CnF, which lies adjacent to the midbrain periaqueductal grey, is a sympathoexcitatory region of the midbrain reticular formation. Sympathoexcitatory responses evoked from the CnF are associated with short-latency excitation of RVLM neurons. 5. Cuneiform nucleus stimulation induces the expression of mRNA for the immediate early genes c-fos and NGFI-A in mid-brain, pontine and hypothalamic structures. 6. The MPFC and CnF are supramedullary structures with opposing modulatory influences on sympathetic vasomotor drive, whose roles in cardiovascular control mechanisms warrant further investigation. 相似文献
6.
AR Santos JC Nery NC Duppre ME Gallo JT Filho PN Suffys WM Degrave 《Canadian Metallurgical Quarterly》1997,46(2):170-172
A case is described in which a pericardial branch of a nongrafted left internal mammary artery communicated directly with the distal left anterior descending artery, following saphenous vein bypass grafting. This type of collateralization following coronary artery bypass surgery seems to be very rare, and perhaps could protect the myocardium from severe ischemia. 相似文献
7.
A Bengtsson L Holm O B?ck J Fransson A Scheynius 《Canadian Metallurgical Quarterly》1997,109(3):533-537
The immunopathology of AD is still unclear, but evidence for an immune response polarized towards Th2 activity has been provided. The CD30 molecule belongs to the tumour necrosis factor (TNF) receptor family and is expressed on activated T cells with a sustained expression in Th2 cells. This molecule also exists in a soluble form (sCD30). Elevated serum levels of sCD30 have been found in patients with Hodgkin's disease, chronic hepatitis B infection and HIV infection. Studies were undertaken to compare the serum levels of sCD30 in patients with AD (n=49) and healthy non-atopic controls (n=94). The presence of sCD30 was analysed with ELISA. A significantly higher concentration of sCD30 was noted in AD patients, median sCD30 level 29 U/ml (range 1-708 U/ml), compared with healthy non-atopic controls (P<0.001), where the median level was 11 U/ml with a range of 1-1042 U/ml. No correlation was found between sCD30 levels and total serum IgE, or between the AD patients' SCORAD values and concentration of sCD30. sCD30 levels were also analysed in 20 AD patients, which during ketoconazole treatment had improved their clinical scores and reduced their serum IgE and eosinophil cationic protein levels. However, no significant decrease in sCD30 levels was noted after treatment. The results show that patients with AD have elevated levels of sCD30, but without correlation to total serum IgE or disease activity. 相似文献
8.
Strains of the gastrointestinal species Lactobacillus reuteri were electrotransformed with plasmid constructs containing the endo-1,3-1,4-beta-glucanase gene (bglM) of Bacillus macerans. The enzyme was expressed and secreted by the lactobacilli. A plasmid construct containing the bglM gene lacking its promoter was derived and was demonstrated to be useful as a promoter probe vector. 相似文献
9.
A sensitive method for measurement of the volume of blood flow through the skin, based on the kinetics of reheating after localised cooling, is described in this paper. This method has been used to study the tuberculin reaction as a model of cutaneous delayed-type hypersensitivity (DHS) in man. Over the positive reaction there is accelerated reheating similar in kinetics and extent to that seen after maximal hyperaemia induced by intradermal injection of histamine or prostaglandin E2. The earlier phase of reheating (10-100 s) is more dependent on blood flow, whereas the later phase (100-300 s) is apparently more dependent on non-perfusion heat exchange mechanisms, including conduction. The reheat kinetic method is largely dependent on blood flow in the deep dermal vessels (diameter > 50 microns), whereas the alternative approach of measurement of the velocity of flow of erythrocytes in the microcirculation by laser Doppler (LD) flowmetry gives results biased towards the most superficial dermal circulation. Previous studies with LD flowmetry have shown that the blood velocity is greatest at the centre of weak and strong reactions, while in the most intense reactions it is raised at the centre but maximal at the periphery (central relative slowing, CRS) raising the possibility of central ischaemia. The reheat kinetics approach has now indicated that the deep dermal circulation is not impaired in CRS reactions. It is concluded that there must be partial obstruction of the parts of the microcirculation communicating between the deep and superficial dermal plexuses, presumably from the accumulation of exudate oedema in the most intense tuberculin reactions. 相似文献
10.
Five different types of cold protective footwear have been tested with regard to their resistance to dry heat loss (i.e. the insulation) with a new electrically heated foot model. The model is able to simulate 'walking' movements in order to provide a more realistic simulation of wear conditions. Thermal insulation of shoes with and without a steel toe cap was the same. The insulating properties during simulated walking movements were 10-25% lower compared with static conditions. For two of the shoe models a significantly lower insulation value for the sole area was obtained when adding a weight of 30 kg. A significant difference could also be found between the insulation values of two different sizes of one of the models. Measurements with the standard method (EN 344) correlated well with the local insulation value of the sole part of the thermal foot. Correlation with the insulation value for the whole shoe was much less, variation was bigger and ranking in terms of cold protection differed between methods. The electrically heated foot model appears to provide a reproducible, accurate and more realistic method for measuring the insulation properties of shoes than EN 344. 相似文献