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701.
702.
By rapid heat treatments surface layers with properties that are distinctly different from those of the initial microstructure can be generated. In case of high nitrogen steels the rapid heat treatment aims at generating a hard surface with compressive residual stresses and high corrosion resistance. Here, the microstructure, the residual stresses and especially the corrosion behaviour of the rapid heat treated high nitrogen steel X30CrMoN15 1 and the reference steel X39CrMo17 1 are presented in dependence of the maximum heat treatment temperature and the heating rate. 相似文献
703.
Low cardiac output was corrected by catecholamines in the course of hemofiltration (HF) administered to 37 patients with multiple organ failure after surgery. Catecholamines (adrenaline hydrochloride, noradrenaline hydrotartrate, dopamine hydrochloride, and dobutamine hydrochloride) were used as monotherapy or in various combinations (two, three, or four drugs). Ninety percent of patients with low cardiac output subjected to HF were administered combined catecholamine therapy. Catecholamines provided the hemodynamic stability of HF in patients with low cardiac output. The frequency of noradrenaline administrations and its mean doses were reliably decreased in the course of HF, whereas the mean doses of adrenaline, dopamine, and dobutamine remained virtually the same. 相似文献
704.
NF Woods M Lentz ES Mitchell M Heitkemper J Shaver 《Canadian Metallurgical Quarterly》1997,20(4):329-340
BACKGROUND AND OBJECTIVE: Various yellow light lasers have been used over the past decade in an attempt to eradicate facial telangiectasia. Based on their power output, spot size, and pulsing characteristics, these lasers belong to one of two categories that exist at either end of a spectrum--high power, short pulse, and large spot size, or low power, long exposure, and small spot size. The copper bromide laser clearly belongs in the latter group, but with higher available power than most other lasers in this group, it exists further along the spectrum toward the region in which the laser parameters might be considered closer to theoretical ideals for treating certain cutaneous vascular pathologies. The objective of this study was to ascertain the role and efficacy of the copper bromide laser on treatment of a variety of facial telangiectasia. STUDY DESIGN/MATERIALS AND METHODS: A total of 570 patients with facial telangiectasia of different diameters and on different regions of the face were treated with the copper bromide laser one or more times and followed up over 5 years. RESULTS: More than 75% clearance was achieved in 70% patients, 50-75% clearance in 17.4% patients, and < 50% clearance in 12.6% patients. Poor results were correlated with anatomical location on the nasal alae and nasal tip and also with vessel size. Very small (< 100 microns) and very large (> 300 microns) vessels did not respond as well as vessels in the 100-300-micron diameter group. Very large vessels responded better to a combination of sclerotherapy and laser treatment. There were no reported long-term adverse effects. CONCLUSION: The copper bromide laser is a safe and effective modality for the treatment of the majority of facial telangiectasia. It is less suited to treating very small vessel lesions such as diffuse erythema, and conversely very large vessels as well as those of the nasal alae. These latter two groups respond better and more permanently to combined sclerotherapy and laser treatment. 相似文献
705.
M Singh JP McGee XM Li W Koff T Zamb CY Wang DT O'Hagan 《Canadian Metallurgical Quarterly》1997,86(11):1229-1233
Polyactide-co-glycolide microparticles, with an entrapped branched octameric peptide from human immunodeficiency virus (HIV-1), were prepared by a solvent evaporation method. The microparticles were characterized for size distribution, antigen loading level, and integrity. Mice in one group were each immunized with a single dose of a controlled-release microparticle formulation containing 300 micrograms of peptide and the serum IgG responses to the antigen were compared with those of mice from a second group that were immunized at 0, 4, and 26 weeks with 100-microgram doses of the same peptide immunogen adsorbed to alum. The controlled-release microparticles induced an antibody response comparable to that from the alum-immunized group. The subcutaneous and the intramuscular routes of administration were compared in additional groups of mice for the microparticles, and both routes induced similar responses. A suspending vehicle for the microparticles was also evaluated and did not affect the immunogenicity of the controlled-release formulation containing both small and large microparticles, although the immunogenicity of smaller microparticles immunized alone was affected. 相似文献
706.
Overweight people are at high risk of developing knee osteoarthritis (OA) and may also be at increased risk of hand and hip OA. Furthermore, being overweight accelerates disease progression in knee OA. While the increased joint stress accompanying obesity may explain the strong linkage between obesity and knee OA risk, it does not necessarily explain why obese people have a high risk of disease in the hand nor why obese women are at higher comparative risk of knee disease than obese men. Unfortunately, studies of metabolic factors linked to obesity have not provided an explanation for these findings. There are a paucity of data on weight loss as a treatment for OA, but preliminary information suggests it is especially effective in knee disease and that even small amounts of weight reduction may have favourable effects. 相似文献
707.
DJ Flint E Paunovich WS Moore DT Wofford CB Hermesch 《Canadian Metallurgical Quarterly》1998,85(6):731-735
Elevated cellular immune responses against the cows' milk protein beta casein have been reported in individuals with Type I diabetes mellitus, a finding supportive of the concept that cows' milk consumption may be causative for the disease. We analysed cellular immune reactivities against beta casein in newly-diagnosed Type I diabetic patients, their immediate autoantibody negative relatives, and unrelated healthy individuals in order to further elucidate the role of anti-beta casein immunity in the pathogenesis of Type I diabetes mellitus. Peripheral blood mononuclear cells were stimulated in vitro with various concentrations of three different beta casein preparations, control antigens (tetanus toxoid, mumps extract) and a mitogen (phytohemagglutinin). The frequency and/or mean simulation index of cellular proliferation against two of the beta casein preparations at high antigen concentrations (i.e. 10 or 50 microg/ml) were significantly higher in newly-diagnosed Type I diabetic subjects compared with autoantibody negative healthy control subjects. However, reactivities against beta casein in the Type I diabetic probands and their autoantibody negative relatives, individuals with a very low-rate of disease development, were almost identical. Cellular immune reactivities to other antigens were similar between the subject groups. In addition to indicating the need for appropriately matched subject populations (e.g. human leukocyte antigen (HLA) matched relatives) when analysing cellular immune responses, these findings support our previous contention that individuals genetically prone to autoimmunity may be deficient in forming tolerance to dietary antigens. However, the significance of anti-beta casein immunity as a specific causative factor in the pathogenesis of Type I diabetes mellitus remains unclear. 相似文献
708.
M Green TV Cacciarelli GV Mazariegos L Sigurdsson L Qu DT Rowe J Reyes 《Canadian Metallurgical Quarterly》1998,66(12):1641-1644
BACKGROUND: The aim of this follow-up study was to assess whether there has been any increase in the percentage of patients offered attempted curative surgery for pancreatic carcinoma and whether the overall survival rate has improved, during the time period 1977-1991. METHODS: Details of new cases of pancreatic carcinoma arising in the population of Malm? during the study period were retrieved from the Local Tumour Register in Lund, Sweden. In all, 740 patients were found; 575 of these were diagnosed before death. Kaplan-Meier analysis was used to calculate overall survival rates, and Cox regression analysis was used to assess survival in relation to year of diagnosis after adjustment for sex, age at diagnosis and stage of disease. RESULTS: Cytological or histopathological evidence of the disease was given in 95 per cent of cases. The overall 5-year survival rate was 0.5 per cent (three of 575). Curative surgery was attempted in 24 patients (4.2 per cent); the proportion undergoing curative surgery increased in the last part of the study. Two of the 24 patients in this group survived for 5 years. CONCLUSION: The prognosis in pancreatic carcinoma remains dismal. Attempted curative surgery still is the only hope for cure, but the group of patients that can be offered this possibility is very limited. In this study, an increase was found in the proportion of patients who were offered attempted curative surgery, but there was no statistically significant increase in the 5-year survival rate following surgery. 相似文献
709.
To investigate the effects of an ethologically-relevant stressor on central and peripheral release of arginine vasopressin and oxytocin, we forced adult male Wistar rats to swim for 10 min and simultaneously measured the release of the two peptides (i) within the hypothalamic supraoptic and paraventricular nuclei (by means of the microdialysis technique) and (ii) into the blood (by chronically-implanted jugular venous catheters). Forced swimming caused a significant rise in the release of arginine vasopressin and oxytocin within both the supraoptic nuclei (four-fold and three-fold, respectively) and the paraventricular nuclei (three-fold and four- to five-fold, respectively). Release patterns measured before, during and after repeated stress exposure on three consecutive days indicated that, at the level of the hypothalamus, the two neuropeptides are critically involved in the rats' stress response in a peptide-, locus- and stress-specific manner. Particularly, despite a general reduction of the recovery of the microdialysis probes over the time, the release of arginine vasopressin within the paraventricular nuclei and of oxytocin within the supraoptic nuclei tended to increase upon repeated stress exposure. Measurement of plasma peptide concentrations revealed that the central release of oxytocin was accompanied by a secretion of this peptide into the systemic circulation. In contrast, arginine vasopressin, assayed in the same plasma samples, failed to respond to the stressor. The latter finding is consistent with a dissociated release of the neuropeptide from different parts of a single neuron (soma/dendrites vs axon terminals). It provides evidence that under physiological conditions plasma hormone levels do not necessarily reflect the secretory activity of central components of the respective neuropeptidergic system. 相似文献
710.
DNA vaccination may work through direct transfection of antigen presenting cells (APC), or by secretion of the encoded protein by muscle or skin cells for uptake by APC. If cytokines are attached to the antigen, they may influence APC or responding T cells to drive the response toward a Th1 or Th2 direction, and/or potentiate it in an antigen-specific manner. To test this concept, expression vectors were constructed containing the ovalbumin (OVA) gene either alone, or linked to cytokine genes including GM-CSF, IFN-gamma, IL-2, IL-4, IL-12, or a sequence encoding nine amino acids of IL-1 beta. These constructs expressed OVA-cytokine fusion proteins in vitro which retained cytokine bioactivity. C57BL/6 mice were injected intramuscularly with the DNA constructs. Little if any OVA-specific antibody was produced in response to any of the DNA constructs, except for OVA-IL-4. However, lymphocytes from BALB/c mice vaccinated with OVA-IL-12 and OVA-IL-1 beta constructs produced more IFN-gamma and less IL-4 during in vitro restimulation assays than did other groups. All constructs elicited OVA-specific cytotoxic responses which were maintained or even increased over 16 weeks. The OVA-IL-12 and OVA-IL-1 beta peptide constructs elicited the strongest cytotoxic responses at 2 weeks postinjection. Cytotoxic responses were seen in all animals, even those lacking OVA-specific Ab, and were not related to Ab level. These studies indicate that the humoral, cytokine, and cytotoxic responses to DNA vaccination can be effectively altered by certain cytokine fusion constructs. 相似文献