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排序方式: 共有727条查询结果,搜索用时 15 毫秒
41.
After intracameral injection calcitonin gene-related peptide has been demonstrated to break the blood aqueous barrier and increase intraocular pressure in rabbits. However in cats, calcitonin gene-related peptide decreases intraocular pressure by increasing the outflow facility of aqueous humor. In the present study, the effect of intracameral injection of calcitonin gene-related peptide on the outflow facility in rabbits has been investigated and the intraocular pressure and outflow facility were measured following intravitreal administration of calcitonin gene-related peptide. The results demonstrate that in spite of the apparent pseudofacility component caused by a breakdown of the blood aqueous barrier also the true trabecular outflow is probably increased in the rabbit eye after intracameral injection of calcitonin gene-related peptide. The intravitreal administration of calcitonin gene-related peptide leaves the blood aqueous barrier intact and causes an increase in the outflow facility of aqueous humor with a concomitant long-lasting decrease in intraocular pressure. 相似文献
42.
YE Appelman JJ Koolen JJ Piek WK Redekop PJ de Feyter S Strikwerda GK David PW Serruys JG Tijssen E van Swijnregt KI Lie 《Canadian Metallurgical Quarterly》1996,78(7):757-762
Registries of excimer laser coronary angioplasty have reported good results in the treatment of complex coronary artery disease, including total or subtotal coronary occlusions. One hundred three patients (103 lesions) with a functional or total coronary occlusion were included in a randomized trial (Amsterdam-Rotterdam [AMRO] trial, total of 308 patients), 49 patients were allocated to laser angioplasty and 54 patients to balloon angioplasty. The primary clinical end points were death, myocardial infarction, coronary bypass surgery, or repeated coronary angioplasty of the randomized segment during a 6-month follow-up period. The primary angiographic end point was the minimal lumen diameter at follow-up in relation to the baseline value (net gain), as determined by an automated contour-detection algorithm. Laser angioplasty was followed by balloon angioplasty in all procedures. The angiographic success rate was 65% in patients treated with excimer laser-assisted balloon angioplasty compared with 61% in patients treated with balloon angioplasty alone. No deaths occurred. There were no significant differences between the laser angioplasty group and the balloon angioplasty group in the incidence of myocardial infarctions (1 patient vs 3, respectively, p = 0.36), coronary bypass surgery (4 patients vs 2, respectively, p = 0.34), repeat angioplasty (10 patients vs 8, respectively, p = 0.46) or primary clinical end point (15 patients vs 12, respectively, p = 0.34). The net gain in minimal lumen diameter and restenosis rate (>50% diameter stenosis at follow-up) were 0.81 +/- 0.74 mm and 66.7%, respectively, in patients treated with laser angioplasty compared with 1.04 +/- 0.68 mm and 48.5%, respectively, in patients treated with balloon angioplasty (p = 0.59 and p = 0.15, respectively). Excimer laser-assisted balloon angioplasty demonstrated no benefit over balloon angioplasty with respect to initial and long-term clinical and angiographic outcome in the treatment of patients with functional or total coronary occlusions of >10 mm in length. 相似文献
43.
DI Watson G Mathew GK Pike RJ Baigrie GG Jamieson 《Canadian Metallurgical Quarterly》1998,85(7):1006-1009
BACKGROUND: This study examined the effect of different types of laparoscopic fundoplication on an incompetent lower oesophageal sphincter to test their effectiveness at preventing gastro-oesophageal reflux in the early postoperative period. METHODS: An experimental porcine model was used. Initial oesophageal myotomy ensured an incompetent lower oesophageal sphincter with free reflux of 'intragastric fluid'. Anterior, posterior or total fundoplication was then performed laparoscopically in 15 laboratory pigs (five in each group). Fundoplication competence and efficacy were determined 2 weeks after laparoscopic antireflux surgery by inflating the stomach with liquid through a gastrostomy cannula. Some animals were also studied at 4 and 6 weeks. Lower oesophageal sphincter pressure was determined using a water-perfused oesophageal manometry catheter incorporating a Dent sleeve. RESULTS: All three types of fundoplication produced similar increases in postoperative resting lower oesophageal sphincter pressure and restored adequate competence to the gastro-oesophageal junction. CONCLUSION: All three variants of laparoscopic fundoplication restore gastro-oesophageal competence in the early postoperative period. 相似文献
44.
45.
CM Maier K Ahern ML Cheng JE Lee MA Yenari GK Steinberg 《Canadian Metallurgical Quarterly》1998,29(10):2171-2180
BACKGROUND and PURPOSE: Mild hypothermia is possibly the single most effective method of cerebroprotection developed to date. However, many questions regarding mild hypothermia remain to be addressed before its potential implementation in the treatment of human stroke. Here we report the results of 2 studies designed to determine the optimal depth and duration of mild hypothermia in focal stroke and its effects on infarct size, neurological outcome, programmed cell death, and inflammation. METHODS: Rats underwent a 2-hour occlusion of the left middle cerebral artery. In the first study (I) animals were kept (intraischemically) at either 37 degreesC (n=8), 33 degreesC (n=8), or 30 degreesC (n=8). Study II consisted of 4 groups: (1) controls (37 degreesC, n=10), (2) 30 minutes of hypothermia started at ischemic onset (33 degreesC, n=9), (3)1 hour (33 degreesC, n=8), and (4) 2 hours (33 degreesC, n=8). Brain temperature was measured by a thermocouple probe placed in the contralateral cortex. After suture removal, all animals were rewarmed and reperfused for 22 hours (I) or 70 hours (II). RESULTS: Mild hypothermia to 33 degreesC or 30 degreesC was neuroprotective (17+/-7% and 27+/-6%, respectively) relative to controls (53+/-8%, P<0.02), but 33 degreesC was better tolerated and recovery from anesthesia was faster. The neurological score of hypothermic animals was significantly better than that of controls (I & II) at both 24 and 72 hours postischemia except for the 30-minute group (II), which showed no improvement. In Study II, 2 hours of hypothermia reduced injury by 59%, 1 hour reduced injury by 84% whereas 30 minutes did not reduce injury. Normalized for infarct size, 2 hours of mild hypothermia decreased neutrophil accumulation by 57% whereas both 1 hour and 30 minutes had no effect. At 72 hours, 1 and 2 hours of mild hypothermia decreased transferase dUTP nick-end labeling (TUNEL) staining by 78% and 99%, respectively, and 30 minutes of hypothermia had no effect. CONCLUSIONS: Intraischemic mild hypothermia must be maintained for 1 to 2 hours to obtain optimal neuroprotection against ischemic cell death due to necrosis and apoptosis. 相似文献
46.
Thymoma in dogs: 23 cases (1980-1991) 总被引:1,自引:0,他引:1
SW Atwater BE Powers RD Park RC Straw GK Ogilvie SJ Withrow 《Canadian Metallurgical Quarterly》1994,205(7):1007-1013
OBJECTIVE: To assess the efficacy of misoprostol for the treatment of chronic erosive gastritis and associated symptoms. METHODS: We performed a double-blind controlled trial, administering 200-micrograms misoprostol tablets or placebo twice daily for 2 months to 48 patients with symptomatic chronic erosive gastritis. Symptomatology was assessed by means of a standard questionnaire at the beginning and at the end of the study, as well as endoscopic and histologic changes of the gastric mucosa. RESULTS: At the end of the treatment period, a significant reduction in symptom score was observed in misoprostol-treated (from 86.6 +/- 66.2 to 17.6 +/- 18.2, p < 0.001) but not in placebo-treated patients. Endoscopic score was significantly reduced at the end of the treatment period in the misoprostol group, compared with that of the placebo group (p < 0.05). A significant reduction in the activity of histologic gastritis was observed only in patients on misoprostol. The prevalence of gastric colonization by Helicobacter pylori was rather low (30%), and no effect of treatment was observed. CONCLUSIONS: Patients with symptomatic chronic erosive gastritis seem to profit from treatment with misoprostol: the treatment with misoprostol, but not with placebo, was effective in significantly reducing the extent of symptoms. Such an improvement was associated with a substantial improvement in the endoscopic and histologic appearance of the gastric mucosa. 相似文献
47.
GK Humphrey AM Herbert S Hazlewood JA Stewart 《Canadian Metallurgical Quarterly》1998,60(7):1188-1196
The interaction between macrophages and oxidatively modified low density lipoprotein (Ox-LDL) appears to play a central role in the development of atherosclerosis, not only through foam cell formation but also via the induction of numerous cytokines and growth factors. The current study demonstrated that Ox-LDL upregulated vascular endothelial growth factor (VEGF) mRNA expression in RAW 264 cells, a monocytic cell line, in a time- and concentration-dependent manner and that Ox-LDL stimulated VEGF protein secretion from the cells. Lysophosphatidylcholine, a component of Ox-LDL, also enhanced VEGF mRNA expression in RAW 264 cells and VEGF secretion from RAW 264 cells, with a maximal effect at a concentration of 10 micromol/L lysophosphatidylcholine. Immunohistochemical studies showed that human early atherosclerotic lesions exhibited intense VEGF immunoreactivity in subendothelial macrophage-rich regions of the thickened intima. In atherosclerotic plaques, VEGF staining was also observed in foam cell-rich regions adjacent to the lipid core or the neovascularized basal regions of plaque consisting predominantly of smooth muscle cells. High-power-field observation revealed that VEGF was localized in the extracellular space as well as at the macrophage cell surface. These observations suggest the possible involvement of Ox-LDL in the development of human atherosclerosis through VEGF induction in macrophages. 相似文献
48.
49.
M Diestelhorst S Dinslage W Konen GK Krieglstein 《Canadian Metallurgical Quarterly》1996,22(10):1465-1470
PURPOSE: To study of the effect of silicone intraocular lens (IOL) implantation using a 3.0 mm tunnel incision with that of implantation though a 6.0 mm corneoscleral incision after phacoemulsification in human eyes. SETTING: Department of Ophthalmology, University of K?ln, Germany. METHODS: In a prospective, randomized clinical study, 50 patients with senile cataract had phacoemulsification and IOL implantation through a 3.0 mm tunnel or a 6.0 mm corneoscleral incision. To assess blood-aqueous barrier (BAB) disruption, preoperative and postoperative sodium fluorescein concentrations in the anterior chamber were measured with the Fluorotron Master II. Diclofenac sodium 0.1% was applied to the operative eyes five times a day for 5 days. The contralateral eyes served as controls. RESULTS: There was no significant between-group difference in sodium fluorescein concentrations in the 5 days after surgery. CONCLUSION: The findings underline our clinical impression that BAB disruption 5 days after surgery does not differ significantly with the type and length of scleral incision used for IOL implantation. 相似文献
50.