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排序方式: 共有832条查询结果,搜索用时 15 毫秒
91.
Several studies since the commencement of fluoridation in 1955 have demonstrated over 50% reduction in mean dmft for 5-year-old Anglesey children in comparison with local control groups. From 1987 fluoridation became intermittent and in 1991 it was terminated. In the present study, carried out in 1993, the total number of children examined was 725 (88.4% of the entire population of 5-year-old school children), of whom 498 had continually resided in specific water distribution zones. The mean dmft for the entire number examined was 2.01 (SD = 3.27). For those who had experienced fluoridation during approximately 35% of their lives (n = 230) it was 1.81 (SD = 2.86) and for those who had experienced fluoridation for less than 10% of their lives (n = 268) it was 2.28 (SD = 3.48). In 1987/88, the last year of optimal fluoridation, the mean dmft of Anglesey 5-year-old children was 0.80 (SD = 1.43) and for those resident on the non-fluoridated Gwynedd mainland it was 2.26 (SD = 3.17). The study demonstrates the serious consequences for dental health when fluoridation is withdrawn and how difficult it will be to reach dental health targets in North Wales without fluoridation. 相似文献
92.
RM Savage BW Lytle S Aronson JL Navia M Licina WJ Stewart NJ Starr FD Loop 《Canadian Metallurgical Quarterly》1997,64(2):368-73; discussion 373-4
BACKGROUND: Intraoperative echocardiography is a valuable monitoring and diagnostic technology used in cardiac surgery. This reports our clinical study of the usefulness of intraoperative echocardiography to both surgeons and anesthesiologists for high-risk coronary artery bypass grafting. METHODS: From March to November 1995, 82 consecutive high-risk patients undergoing coronary artery bypass grafting were studied in a four-stage protocol to determine the efficacy of intraoperative echocardiography in management planning. Alterations in surgical and anesthetic/hemodynamic management initiated by intraoperative echocardiography findings were documented in addition to perioperative morbidity and mortality. RESULTS: Intraoperative echocardiography initiated at least one major surgical management alteration in 27 patients (33%) and at least one major anesthetic/hemodynamic change in 42 (51%). Mortality and the rate of myocardial infarction in this consecutive high-risk study population using intraoperative echocardiography and in a similar group of patients without the use of intraoperative echocardiography was 1.2% versus 3.8% (not significant) and 1.2% versus 3.5% (not significant), respectively. CONCLUSIONS: We conclude that when all of the isolated diagnostic and monitoring applications of perioperative echocardiography are routinely and systematically performed together, it is a safe and viable tool that significantly affects the decision-making process in the intraoperative care of high-risk patients undergoing primary isolated coronary artery bypass grafting and may contribute to the optimal care of these patients. 相似文献
93.
94.
B Sporer R Paul U Koedel R Grimm M Wick FD Goebel HW Pfister 《Canadian Metallurgical Quarterly》1998,178(3):854-857
To determine whether matrix metalloproteinase (MMP)-9 is a potential mediator involved in the frequently detected blood-brain barrier leakage in human immunodeficiency virus (HIV)-infected patients, zymography was used to detect MMP-9 activity in cerebrospinal fluid (CSF) samples of 80 HIV-infected patients and of 10 control patients. CSF MMP-9 activity was detected in 40% of HIV-infected patients (but not in controls) and was significantly more frequent in HIV-infected patients than in those without neurologic deficits (50% vs. 13.6%). The frequency of CSF MMP-9 activity did not significantly differ between neurologically symptomatic HIV-infected patients with or without opportunistic central nervous system disease (51.6% vs. 48.1%). Additionally, the presence of CSF MMP-9 activity in HIV-infected patients was associated with an increased CSF white blood cell count and an elevated CSF-to-serum albumin ratio, suggesting that it may play a role in blood-brain/CSF barrier leakage in HIV-infected patients. 相似文献
95.
PURPOSE: To evaluate the toxic effect of vancomycin on the corneal endothelium related to concentrations of vancomycin. METHODS: The toxic effect is assessed with a weighing method that gives a measure of endothelial function. Thirty-three rabbit corneas were divided into four groups. Three groups of seven corneas each were exposed to concentrations of 1.0 mg/ml, 3.0 mg/ml and 5.0 mg/ml vancomycin, respectively. The fourth group of twelve corneas served as a control group. RESULTS: The corneas exposed to 1.0 mg/ml vancomycin showed no significant weight increase, while the corneas exposed to 3.0 mg/ml and 5.0 mg/ml showed a significant weight increase as compared to the control corneas. The weight increase was significantly larger in the group of corneas exposed to 5.0 mg/ml as compared to 3.0 mg/ml. CONCLUSIONS: In the interval of tested concentrations there is a dose response relationship between vancomycin concentrations and endothelial toxicity. This experiment shows that vancomycin in the concentration of 1.0 mg/ml is non-toxic to the endothelium, while 3.0 mg/ml and 5.0 mg/ml increasingly impair endothelial function. 相似文献
96.
Six patients were examined by CT following head trauma, with bleeding from the ear and trismus. The mandibular condyles were normal and MRI in two patients demonstrated a normally located meniscus. An unilateral comminuted temporal bone fracture (TBF) with multiple fracture lines and one or more fragments detached from the petrous bone was demonstrated by CT in every patient. On physical examination there was trismus, inability to chew and local pain in the temporomandibular joint (TMJ) without tenderness and swelling. Measurements of vertical and horizontal mandibular movement unequivocally demonstrated TMJ malfunction in comparison with 10 controls. The malfunction was presumably due to instability of the fractured petrous bone, base of the TMJ. Immobilising one TMJ results in blocking of both joints. Clinical improvement in 6-8 months and absence of symptoms of joint derangement on repeated physical examination were thought to be explained by restored petrous bone stability following healing of the fractures. The phenomenon of trismus following TBF with normal TMJ is rare and not yet reported. 相似文献
97.
ES Pizer C Jackisch FD Wood GR Pasternack NE Davidson FP Kuhajda 《Canadian Metallurgical Quarterly》1996,56(12):2745-2747
One of the key limiting factors in the treatment of advanced stage human epithelial malignancies is the lack of new, selective molecular targets for antineoplastic therapy. A substantial subset of human breast, ovarian, endometrial, colorectal, and prostatic cancers express elevated levels of fatty acid synthase, the major enzyme required for endogenous fatty acid biosynthesis, and carcinoma lines are growth inhibited by cerulenin, a noncompetitive inhibitor of fatty acid synthase. We have shown previously that the difference in fatty acid biosynthesis between cancer and normal cells is an exploitable target for metabolic inhibitors in the in vitro setting and in vivo in a human ovarian carcinoma xenograft in nude mice. Here, we report that cerulenin treatment of human breast cancer cells inhibits fatty acid synthesis within 6 h after exposure, that loss of clonogenic capacity occurs within the same interval, and that DNA fragmentation and morphological changes characteristic of apoptosis ensue. 相似文献
98.
99.
Biomedical amplifiers using integrated circuits 总被引:1,自引:0,他引:1
100.
Isolated fat cells from 3, 12 and 28 month old rats were compared intheir lipolytic response to various doses of L-epinephrine. With increasing age a progressive decline in the response occurred when comparing rats with unmatched mean adipocyte diameters. However, this apparently age-related decrease was no longer evident if the diameters were matched since the 28 month old animals had a lipolytic response less than the 3 month old rats but greater than the 12 month olds. Body weight differences between these ages may account for these observations. The biphasic dose response curve to hormone stimulation in the 3 and 12 month olds was monophasic at 28 months. Within each age group the initial lag in glycerol release decreased and the lipolytic response increased as mean cell size increased. The rate of hormone stimulated glycerol release varied inversely with incubations of 3,700 to 25,000 cells/ml and aging had no effect on this parameter. DNA content per fat cell remained constant with age. 相似文献