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101.
H Nakanishi RM Taylor AL Hawkins CA Griffin GR Martin A Passaniti 《Canadian Metallurgical Quarterly》1994,58(4):592-601
Three stable carcinoma cell lines, designated RM22-F5, RM17-5R, and RM1-4, were established from spontaneously occurring mammary carcinomas in old, outbred, female Wistar rats. The RM22-F5 and RM17-5R cells were keratin-positive and formed epithelial monolayers, whereas RM1-4 cells exhibited a spindle-like morphology and intense vimentin staining. When injected into nude mice, RM22-F5, RM17-5R and RM1-4 cells formed well-differentiated, poorly differentiated and undifferentiated carcinomas, respectively. The relative growth rates of the tumor cells in vitro were RM1-4 > RM22-F5 > RM17-5R. The growth of RM22-F5, but not of RM17-5R and RM1-4 cells, was significantly stimulated by insulin, epidermal growth factor, dexamethasone, 17 beta-estradiol and progesterone in vitro. Ovariectomy reduced the growth of RM22-F5 cells in vivo and these cells (but not RM1-4 or RM17-5R) were estrogen-receptor (ER)-positive. None of the lines were positive for the progesterone receptor (PR). Spontaneous lung and lymph-node metastases were observed in nude mice injected with RM22-F5 or RM17-5R cells, respectively. In contrast, RM1-4 cells were non-metastatic but invasive. Karyotype analysis revealed that RM22-F5 cells were hyperdiploid, RM17-5R were hypotetraploid, and RM1-4 were diploid with a sizeable insertion in chromosome 1. A point mutation in codon 12 (G to A transition) and loss of the normal allele of the H-ras-1 gene was detected in the DNA from RM22-F5 cells. No p53 mutations were apparent in any of the cell lines. The results indicate that RM22-F5 cells are hormone-dependent with an ER+/PR- phenotype, while the RM17-5R and RM1-4 lines are hormone-independent and ER-/PR-. These cell lines exhibit the spectrum of biological properties and genetic alterations observed in human breast cancers and may, therefore, be novel and useful models for understanding sporadic breast cancer in post-menopausal women. 相似文献
102.
OBJECTIVE: The purpose of this study was to evaluate both morphology and blood flow in peripheral arteries with occlusive lesions using MR angiography (MRA) and velocity-encoded cine MRI. MATERIALS AND METHODS: Two-dimensional time-of-flight MRA and velocity-encoded cine MRI were performed in nine patients with peripheral arterial occlusive disease. Findings on MR angiograms were verified by conventional angiography. RESULTS: All the stenotic lesions in the popliteal arteries were depicted by MRA. The degree of the stenoses in the artery was overestimated by MRA. Major collateral circulations were demonstrated. Velocity-encoded cine MRI provided flow velocity information on the arteries above and below the stenoses. The flow velocity waveform was monophasic above and below the stenosis. The peak systolic velocity in the artery below the stenosis was reduced compared with that above the stenosis (p < 0.05). CONCLUSION: The combination of MRA and velocity-encoded cine MRI has clinical potential for the evaluation of peripheral arterial occlusive disease. 相似文献
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105.
GR Kinghorn 《Canadian Metallurgical Quarterly》1998,9(9):497-500
The effects of reactive oxygen species (ROS) on elastin molecules (tropoelastin) were studied in vitro. ROS generated by ultraviolet A and hematoporphyrin rapidly degraded tropoelastin within 5 min. Their degradative activity was inhibited by the addition of NaN3. Treatment of tropoelastin with copper sulfate/ascorbic acid resulted in degradation of tropoelastin producing fragments of molecular weight 45, 30 and 10 kDa within 30 min. The degradation of tropoelastin was partially blocked by the addition of mannitol. ROS induced by the xanthine/xanthine oxidase system also degraded tropoelastin within 6 h. The degradation was blocked by catalase but not by superoxide dismutase (SOD). ROS generated by copper-ascorbate seems to be unique in that it cleaves relatively specific sites of the tropoelastin molecule. Thus ROS may play a degradative role in elastin metabolism which may cause the elastolytic changes or the deposition of fragmented elastic fibers in photoaged skin or age-related elastolytic disorders. 相似文献
106.
MM Kockx GR De Meyer J Muhring W Jacob H Bult AG Herman 《Canadian Metallurgical Quarterly》1998,97(23):2307-2315
BACKGROUND: The transition of a fatty streak into an atherosclerotic plaque is characterized by the appearance of focal and diffuse regions of cell death. We have investigated the distribution of apoptotic cell death and apoptosis-related proteins in early and advanced atherosclerotic lesions. METHODS AND RESULTS: Human atherosclerotic plaques were studied by whole-mount carotid endarterectomy specimens (n=18). This approach allowed comparison of adaptive intimal thickenings, fatty streaks, and advanced atherosclerotic plaques of the same patient. The fatty streaks differed from adaptive intimal thickenings by the presence of BAX (P<0.01), a proapoptotic protein of the BCL-2 family. Both regions were composed mainly of smooth muscle cells (SMCs), and macrophage infiltration was low and not different. Apoptosis, as detected by DNA in situ end labeling (terminal deoxynucleotidyl transferase end labeling [TUNEL] and in situ nick translation) was not present in these regions. Apoptosis of SMCs and macrophages, however, was present in advanced atherosclerotic plaques that were present mainly in the carotid sinus. A dense infiltration of macrophages (5.8+/-3% surface area) was present in these advanced atherosclerotic plaques. Cytoplasmic remnants of apoptotic SMCs, enclosed by a cage of thickened basal lamina, were TUNEL negative and remained present in the plaques as matrix vesicles. CONCLUSIONS: We conclude that SMCs within human fatty streaks express BAX, which increases the susceptibility of these cells to undergo apoptosis. The localization of these susceptible SMCs in the deep layer of the fatty streaks could be important in our understanding of the transition of fatty streaks into atherosclerotic plaques, which are characterized by regions of cell death. Matrix vesicles are BAX-immunoreactive cytoplasmic remnants of fragmented SMCs that can calcify and may be considered the graves of SMCs that have died in the plaques. 相似文献
107.
An experimental investigation has lately shown that certain allyl compounds of garlic are able to provoke acantholysis in normal human skin cultured in vitro. The acantholytic effect has been more prominent in the samples from DR4+ donor. We here report a case of superficial pemphigus which appeared spontaneously in a DR4,14+, 49-year-old man and which ran a course that proved to be affected by dietary factors, in particular by the consumption of garlic. In the absence of a conventional treatment and on a garlic-free diet only, the disease ceased for several months. Soon after an unintentional dietary test with a strongly and presumable garlic-spiced fish meal, the pemphigus recurred. Nutritional factors should be added to the ever-growing list of exogenous factors capable of inducing or perpetuating pemphigus in genetically predisposed individuals. 相似文献
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109.
GR Auleley P Ravaud B Giraudeau L Kerboull R Nizard P Massin C Garreau de Loubresse C Vallée P Durieux 《Canadian Metallurgical Quarterly》1997,277(24):1935-1939
OBJECTIVES: To assess the impact of the implementation of the Ottawa ankle rules on radiography requests in French hospitals during a 5-month intervention period and the impact of using posters alone to sustain the effect of the rules during a 5-month postintervention period. DESIGN: Multicenter randomized controlled trial preceded and followed by observational studies of radiological practices. SETTING: The emergency departments of 5 Paris university teaching hospitals of the Assistance Publique-H?pitaux de Paris. PATIENTS: A total of 2218, 1911, and 851 patients-all aged 18 years and older-who were seen for acute ankle or midfoot injuries in emergency departments during preintervention, intervention, and postintervention periods, respectively. INTERVENTION: Implementation of the Ottawa ankle rules by emergency department physicians in the intervention hospitals (using meetings, posters, pocket cards, and data forms). During the postintervention period, posters alone were used to sustain the intervention effect. MAIN OUTCOME MEASURE: Percentage of patients for whom radiography was requested. RESULTS: During the preintervention period, 98% and 98.5% of patients were referred for radiography in the intervention and control groups, respectively. During the intervention period, the mean proportions of patients referred for radiography by physicians was 78.9% in the intervention group and 99% in the control group (P=.03). Between preintervention and intervention periods, a relative reduction of 22.4% (95% confidence interval [CI], 19.8%-24.9%) in radiography requests was observed in the intervention group, while requests increased by 0.5% (95% CI, 0%-1.4%) in the control group. During the postintervention period, the proportion of radiography requests in the intervention hospitals was lower than the proportion observed in the preintervention period (83.1% vs 98%). CONCLUSIONS: Implementation of the Ottawa ankle rules significantly reduced radiography requests in French hospitals. Using a minimal postintervention implementation strategy, the effect of this intervention decreased but persisted after it was discontinued. 相似文献
110.
The spleen is the most commonly injured organ in blunt abdominal trauma. There remains much controversy in the diagnosis and management of the injured spleen, with a recent trend toward nonoperative management. A 5-year period was reviewed at a rural, Level I trauma center to address issues of operative versus nonoperative management. During this time period, there were 136 patients identified as having trauma to the spleen. Most (95%) were the result of blunt trauma, and a majority of these were from motor vehicle accidents. Computed tomography was the most frequent method of diagnosis. Approximately half of the patients underwent immediate operative intervention. Of those initially observed, 10 patients (16%) eventually were operated on. Most of the cases were due to underestimation of the severity of the splenic injury, and most received blood transfusion. This experience suggests that observation for splenic trauma is appropriate in many cases, as long as the surgeon is certain the spleen is not actively bleeding and the patient will not require blood transfusion. 相似文献