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21.
Mosaad A M Abou-Seif Mohammad M El-Naggar Mohammad El-Far Mohsen Ramadan Nivin Salah 《Clinical chemistry and laboratory medicine》2003,41(7):926-933
The formation of superoxide partially accounts for the well-known oxygen enhancement of radiation-induced biochemical changes and cell damage. Radioprotective effects of copper (II), manganese (IV) or vanadium (IV) complexes, of superoxide dismutase-mimetic activity, on body weight, survival rate and some biochemical parameters in pre-treated irradiated, untreated irradiated and treated non-irradiated female albino rats have been studied 24 h after whole body gamma-irradiation at a dose level of 6 Gy. Survival time, body weight, red blood cell (RBC) and white blood cell (WBC) counts, hemoglobin (Hb) concentration, percentage of hematocrit (Hct%), reduced glutathione (GSH), serum total protein, albumin, globulin (G), blood urea, creatinine and cholesterol were estimated, as well as the activities of blood superoxide dismutase (SOD), glutamate-oxaloacetic (GOT) and glutamate-pyruvic (GPT) transaminases, and alkaline phosphatase were assessed. A significant decline was shown in body weight, survival rate, the mean values of RBC and WBC counts, Hb and Hct percentages, and GSH concentration, as well as blood SOD activity, in whole body gamma-irradiated rats compared with the control non-irradiated rat group. The mean activity values of alkaline phosphatase, GOT and GPT, as well as the average values of blood urea, creatinine, total cholesterol, total protein and globulin were significantly elevated, while the average values of albumin and the albumin/globulin ratio were decreased in gamma-irradiated rats compared with the corresponding values of the normal control rat group. Pretreatment of rats with either manganese or vanadium complexes resulted in a significant increase in survival rate and body weight over that of the non-treated irradiated rat group. Pretreatment of rats with copper (II), manganese (IV) or vanadium (IV) complexes caused a significant increase in RBC and WBC counts, Hb concentration, HCt (%), GSH content and SOD activity in blood when compared to the irradiated rat group without treatment. The administration of copper (II), manganese (IV) or vanadium (IV) complexes prior to irradiation exposure resulted in a significant decrease in GOT and GPT activities in addition to blood urea, creatinine, cholesterol, globulin and total protein contents, while each complex exhibited a significant increase in plasma alkaline phosphatase, albumin, and the albumin/globulin ratio compared to the untreated irradiated rat group. Administration of vanadium (IV), manganese (IV) or copper (II) complexes in non-irradiated rats caused a significant increase in SOD activity without changing other biochemical parameters compared with the corresponding values of the normal control rat group. We conclude that these metallo-elements, particularly manganese (IV) and vanadium (IV) complexes of 2-methylaminopyridine, have radiation protection and radiation recovery. Furthermore, these metal complexes offer a new approach to overcome the pathological effects of ionizing radiation and suggest their use as a physiological approach to preventing or perhaps predominantly facilitating recovery from radiation injury. 相似文献
22.
Mahmoud R Hussein Dalia A Elsers Sabah A Fadel Abd-Elhady M Omar 《European journal of cancer prevention》2006,15(1):64-68
Although melanocytic skin lesions have been recognized since antiquity, their literature was limited to Caucasians. To date, the clinicopathologic features of these lesions in Egyptians are still unknown. To define these features, diagnostic records of the melanocytic skin lesions received at the Pathology Department, Assuit University Hospitals (1989-2004) were reviewed. The lesions examined included 12 benign naevi (BN), 10 dysplastic naevi (DN), and 21 cutaneous malignant melanomas (CMMs). The DN and CMMs were more common in men than in women (2 : 1 and 1.5 : 1, respectively) while BN were more common in women (2 : 1). The average age incidence was 33+/-5, 38+/-7 and 54+/-3 years, for BN, DN and CMM, respectively. The lower limb (13/21, 62%), head and neck (7/21, 33%) were the most common sites for CMMs. The average size (mm) was 2+/-0.3, 4+/-0.6 and 21+/-0.3 for BN, DN and CMMs, respectively. Recurrence occurred in 10% of CMMs. Histologically, CMMs were of nodular type and composed of epithelioid (7/21, 33%), spindle cells (1/21, 5%), or mixed cells (13/21, 62%). The mean tumour thickness (Breslow) was 6+/-0.5 mm. CMMs included two of 21(9%), three of 21(14%), six of 21(38%), and 10 of 21(38%) with Clark level II, III, IV and V. In Egypt, CMM is the third most common cutaneous neoplasm following squamous and basal cell carcinomas. Compared with Western societies, melanoma has a male sex predilection, similar histological features but different topographical distribution and rare incidence. The striking difference from Western series is the incidence of nodular melanoma - in the West this represents 15-30% of melanomas, with superficial spreading being the majority. Another key difference from the West is the 'sun-bed' culture of the West and the desire to have suntans. This is the first study that reports the clinicopathologic features of melanocytic skin lesions in Egypt. 相似文献
23.
T. M. Skerry M.D. M.R.C.V.S. R. Suswillo A. J. El Haj N. N. Ali R. A. Dodds L. E. Lanyon 《Calcified tissue international》1990,46(5):318-326
Summary Previous studies of Alcian blue-induced birefringence in adult avian cortical bone showed that a short period of intermittent
loading rapidly produces an increased level of orientation of proteoglycans within the bone tissue. In the absence of further
loading, this persists for over 24 hours. We have proposed that this phenomenon could provide a means for “capturing” the
effects of transient strains, and so provide a persistent, constantly updated strain-related influence on osteocyte populations
related to the bones' averaged recent strain history, in effect, a “strain memory” in bone tissue. In our present study, we
use the Alcian blue-induced birefringence technique to demonstrate that proteoglycan orientation also occurs after intermittent
loading of both cortical and cancellous mammalian bonein vivo andin vitro. We also show that the change in birefringence is proportional to the magnitude of the applied strain, and that the reorientation
occurs rapidly, reaching a maximal value after only 50 loading cycles. Examination of electron micrographs of bone tissue
after staining with cupromeronic blue allows direct visualization and quantification of the change in proteoglycan orientation
produced by loading. This shows that intermittent loading is associated with a realignment of the proteoglycan protein cores,
bringing them some 5 degrees closer to the direction of collagen fibrils in the bone matrix. 相似文献
24.
Mokhtar Elhakim Magdy Nafie Khalaf Mahmoud Azza Atef 《Journal canadien d'anesthésie》2002,49(9):922-926
PURPOSE: The combination of antiemetic drugs could be a solution to prevent severe postoperative nausea and vomiting (PONV). The aim of this randomized double blind, dose-ranging study was to determine the minimum single effective dose of dexamethasone combined with ondansetron for the prevention of PONV in patients undergoing laparoscopic cholecystectomy. METHODS: One hundred eighty patients were allocated randomly to one of six groups to receive saline (P group), ondansetron 4 mg (O group), or ondansetron 4 mg and dexamethasone at doses of 2 mg (OD2 group), 4 mg (OD4 group), 8 mg (OD8 group), and 16 mg (OD16 group). A standardized general anesthetic was used. All episodes of PONV during the intervals of zero to six hours, 6-12 hr and 12-24 hr after surgery were evaluated using a numeric scoring system. Mean visual analogue scale pain scores at rest and on movement, the time to first demand of analgesia, total analgesic consumption in 12 hr epochs, duration of hospital stay, and side effects were recorded. RESULTS: The incidence of PONV in the OD8 (16%) and OD16 (16%) groups was lower than in the 83% (P < 0.001) and O groups (50%) at the 12-24 hr epoch (P < 0.05). There were no differences in antiemetic effect between the O, OD2 and OD4 groups and between the OD8 and OD16 groups. Pain scores, total analgesic consumption, duration of hospital stay and side effects were similar among groups. CONCLUSION: Our results suggest that 8 mg is the minimum dose of dexamethasone that, combined with ondansetron 4 mg will effectively prevent PONV in patients undergoing laparoscopic cholecystectomy. 相似文献
25.
Disposition and hypoglycaemic action of glipizide in diabetic patients given a single dose of nifedipine 总被引:4,自引:0,他引:4
A. A. Connacher A. H. El Debani T. E. Isles I. H. Stevenson 《European journal of clinical pharmacology》1987,32(1):81-83
Summary Adrenaline, when administered in dental local anaesthetic solutions, significantly reduces the plasma potassium concentration in young healthy adults. This effect occurs within 10 min of extravascular injections into the maxillary buccal sulcus and may influence the choice of local anaesthetic solution for patients receiving kaliuretic diuretics. 相似文献
26.
H Hachimi A Oudidi N Benmansour H Kadaoui Z Zaki M Ridal M N El Alami 《Tropical dental journal》2005,28(112):24-26
The cementoblastoma is a rare benign tumor of odontogen origin that interests the roots of the teeth especially the lower molars. The evolution is often silent, the radiological exam is not specific, the diagnosis of certainty is histological. The surgical treatment assures the recovery without aftermath. The authors report a case of cementoblastoma at a patient of 37 years for which he has benefited of a resection by vestibular way and debate diagnosis and therapeutic modes of this affection. 相似文献
27.
Cyclodextrin formulation of dorzolamide and its distribution in the eye after topical administration. 总被引:2,自引:0,他引:2
Hakon H Sigurdsson Einar Stefánsson Elínborg Gudmundsdóttir Thór Eysteinsson Margrét Thorsteinsdóttir Thorsteinn Loftsson 《Journal of controlled release》2005,102(1):255-262
Due to limited aqueous solubility of dorzolamide at physiologic pH, the pH of Trusopt eye drops (cont. 2% dorzolamide) has to be kept at about 5.65, and to increase the topical bioavailability of the drug from Trusopt the contact time of the drug with the eye surface is increased by increasing the viscosity of the eye drops to 100 cps. This low pH and high viscosity can lead to local irritation. In this study, dorzolamide hydrochloride was formulated as 2% and 4% low viscosity solutions (viscosity 3 to 5 cps) containing randomly methylated beta-cyclodextrin at pH 7.45. These formulations were evaluated in rabbits. The animals were sacrificed at various time points after topical administration of the drug and the dorzolamide concentration determined in the different parts of the eye. Trusopt was used as a reference standard. The topical availability of dorzolamide from the cyclodextrin-containing eye drops appeared to be comparable to that from Trusopt and the drug reached retina and optic nerve to give measurable concentrations for at least 8 h after administration of the eye drops. 相似文献
28.
Youness El harrech Hassan Jira Jaouad Chafiki Mohamed Ghadouane Ahmed Ameur Mohamed Abbar 《Actas urologicas espa?olas》2009,33(1):93-96
Nutcracker syndrome is caused by compression of the left renal vein between the aorta and the superior mesenteric artery where it passes in the fork formed at the bifurcation of these arteries. The phenomenon results in left renal venous hypertension. The syndrome is manifested by left flank and abdominal pain, with or without unilateral haematuria. The nutcracker syndrome has been treated in various ways. We report one case of the syndrome and discuss the place of surveillance in its management. 相似文献
29.
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