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91.
92.
In this study we aimed to evaluate the in vivo effects of myrtle oil (myrtii oleum) on the antioxidant enzymes such as superoxide dismutase and catalase, the levels of malondialdehyde in liver tissues as an index of lipid peroxidation and nitrite–nitrate levels in normoglycaemic and alloxan-induced diabetic and MO-treated rabbits. In our previous study, we assumed that MO with a dose of 50 mg/kg, possesses a hypoglycemic activity and this activity was independent from the effects of insulin. Myrtle oil exerts its hypoglycemic activity by enhanced glycolysis, glycogenesis and decreased glycogenolysis. What is more glucose load data strongly suggest that MO treatment produces hypoglycemia mainly by reducing intestinal absorption of glucose, so MO could be an -glycosidase enzyme inhibitor which had a hypoglycaemic effect only on alloxan-induced diabetic rabbits on the fourth hour and on orally glucose loaded group. The major finding of this new study is that, MO may not offer any protection against oxidative stress during acute studies in normoglycemic and diabetic groups. Although the levels of superoxide dismutase and catalase enzyme activities did not change during acute studies in diabetes + MO group, there was a significant change at the end of 21 days. There is a very limited knowledge about MO and its effects on diabetes. Therefore, we tried to explain the mechanism that might underlie the protective effects of MO with this paper.  相似文献   
93.
Two methods are described for the determination of theophylline (THP) and ephedrine hydrochloride (EPH) in combined pharmaceutical tablet forms. The first method depends on the use of the first derivative of the ratio-spectra obtained by dividing the absorption spectrum of binary mixtures by a standard spectrum of one of the compounds. The first derivative amplitudes at 231.8 and 250.3 nm were selected for the assay of THP and EPH, respectively. Calibration graphs were established for 20-180 microg ml(-1) for THP and 10-50 microg ml(-1) for EPH. The second method is based on high-performance liquid chromatography on a reversed-phase column using a mobile phase of methanol-water (40+60,v/v) (pH 3) with detection at 217 nm. Linearity was obtained in the concentration range of 5-150 microg ml(-1) for THP and 15-75 microg ml(-1) for EPH. The detection limits for THP and EPH were 0.73 and 0.92 microg ml(-1) by ratio-spectra derivative spectrophotometry and 0.59 and 0.86 microg ml(-1) by HPLC, respectively. The proposed methods were successfully applied to the determination of these drugs in laboratory-prepared mixtures and in tablets. The relative standard deviations were found to be less than 1.5%, indicating reasonable repeatibility of both methods.  相似文献   
94.
In this study we aimed to determine the role of piracetam (PIR) in preventing radiation induced cochlear damage after total-cranium irradiation (radiotherapy; RT). Male albino guinea pigs used in the study were randomly divided into three groups. Group 1 (Control group) (n=11) received neither PIR nor irradiation, but received saline solution intraperitoneally (i.p.) and received sham irradiation. Group 2 (RT group) (n=32) was exposed to total cranium irradiation of 33 Gy in 5 fractions of 6.6 Gy/d for five successive days, with a calculated (alpha/beta=3.5) biological effective dose of fractionated irradiation equal to 60 Gy conventional fractionation, then received saline solution for five successive days i.p. Group 3 (PIR+RT group) (n=33) received total cranium irradiation, plus 350 mg/kg per day PIR for five successive days i.p. After the last dose of RT, the guinea pigs were all sacrificed at the 4th, 24th and 96th hours, respectively. Their cochleas were enucleated for histopathologic examination. It was observed that total cranium irradiation (RT group) promoted degeneration in stria vascularis (SV), spiral ganglion cells (SG), outer hair cells (OHC) and inner hair cell (IHC) of cochleas at these times (p<0.05). While in the PIR+RT group, there was no statistically significant difference on radiation-induced cochlear degeneration in SV and OHC at 4th (p>0.05) and IHC at 4th, 24th hours (p>0.05), there was a significant difference on radiation-induced cochlear degeneration in SV and OHC at 24th and 96th hours (p<0.05), IHC at 96th hour (p<0.05) and SG at 4th, 24th and 96th hours (p<0.05). There was no any cochlear degeneration in the control group. Piracetam might reduce radiation-induced cochlear damage in the guinea pig. These results are pioneer to studies that will be performed with PIR for radiation toxicity protection.  相似文献   
95.

Introduction

In Mini-Nutritional Assessment-Short Form (MNA-SF) test, a practical and reliable alternative parameter is still necessary for patients with difficult body mass index evaluation. We aimed to show whether or not handgrip strength may be used instead of body mass index (BMI) in MNA-SF test.

Materials and Methods

MNA-SF test scores, calf circumferences (CC), handgrip strength (HGS), and BMI of 191 patients were evaluated. The first one of calculated MNA-SF tests was with BMI, the second one with CC, and the last one with HGS. Zero point was given if CC was <31 cm and 3 points were given if CC was ≥31 cm. Zero, 1, 2, and 3 points were given if the loss of HGS when compared to expected HGS were ≥%60, from ≥%30 to <%60, from ≥%10 to <%30, and <%10 or greater than expected HGS, respectively. MNA-SF scores and nutritional status according to these three measures were compared.

Results

Mean age and median MNA-SF scores of the patients were 75±7.6 years and 12 points (min-max: 0-14) respectively. There were strongly positive correlations between MNA-SF scores with BMI and CC, with BMI and HGS, and with CC and HGS (r=0.938 p<0.001, r=0.938 p<0.001, r=0.914 p<0.001, respectively). Substantial agreement in nutritional status of the patients were seen between MNA-SF groups with BMI and CC, with CC and HGS, and with BMI and HGS (kappa: 0.795 p<0.001, kappa: 0.709 p<0.001, and kappa: 0.760 p<0.001, respectively).

Conclusions

HGS might be considered instead of BMI in MNA-SF test to assess nutritional status of geriatric patients.
  相似文献   
96.
Abstract

Purpose: To compare the efficacy, safety, and potential advantages of the preservative-free versus preserved brimonidine %0.15 preparations in patients with primer open-angle glaucoma (POAG) or ocular hypertension (OHT).

Methods: Forty-two eyes of the 21 treatment-naive patients with POAG or OHT were enrolled in this study. Eyes were randomly assigned to receive brimonidine-purite 0.15% or preservative-free brimonidine 0.15% two times daily. Efficacy of the two eye drops was assessed by measuring the intraocular pressure (IOP) at 9–10 am at baseline and week 4. Safety and potential advantages of the drops were evaluated at weeks 4 in terms of ocular symptoms and tear parameters. Ocular symptom values of the patients were evaluated with a scale of 0–4 (0?=?no discomfort and 4?=?severe discomfort).

Results: Both of the brimonidine tartrate formulations resulted in statistically similar IOP reduction (preserved formulation; ?5.2?mmHg [22.9% reduction] preservative-free formulation; ?5.7?mmHg [24.1% reduction], p?=?0.37). It was found that brimonidine tartrate formulations with and without topical preservatives did not produce a statistically significant difference in pain, stinging, and blurred vision at the upon instillation (p?>?0.05). However, the burning sensation was significantly higher in the preservative-free formulation at the first instillation compared to the preserved formulation (p?=?0.01). Also, there was no statistically significant difference between the two formulations in terms of symptoms (itching, burning, tearing, stinging, and photophobia) and tear parameters during the day (p?>?0.05).

Conclusions: Although topical preservative-free brimonidine tartrate treated eyes had a more burning sensation at the first drop, the two formulations were similar in terms of ocular tolerability in the short term period. Also, both formulations were found to reduce IOP at a similar rate.  相似文献   
97.
Sympathetic skin response in patients with chronic renal failure   总被引:1,自引:0,他引:1  
Sympathetic skin response (SSR) was measured in 20 normal healthy subjects and in 22 patients with chronic renal failure on regular hemodialysis, and its correlation with abnormalities of sensorimotor nerve conduction study and clinical autonomic symptoms was investigated. Nerve conduction studies (NCS) were abnormal in 17 of 22 patients (77.3%), and SSR was absent in 14 of 22 patients (63.6%). Patients were divided into three groups based on their SSR response: patients with normal SSR (n:8, 36.4%), patients with absent SSR in the foot only (n:9, 40.9%), and patients with absent SSR in both hand and foot (n : 5, 22.7%). Good correlation between abnormalities of NCS and absent SSR was observed. No correlation was noted between patient age, sex, duration of hemodialysis, duration of renal failure history, and absent SSR. However, statistically significant correlation was found between mean amplitude of the foot SSRs and sensorimotor nerve conduction velocities, and weekly frequency of hemodialysis.  相似文献   
98.
A bstract The purpose of this study was to investigate the risk of perioperative major cere-brovascular events (MCVEs) in patients undergoing coronary artery bypass grafting (CABG) and to develop preventive therapy. After excluding the patients with marked ascending aortic atheromas and those with combined intracardiac procedures such as valve replacement and aneurysmectomy, 722 consecutive patients who had carotid artery duplex scanning (CADS) and CABG were studied. The results of the study showed the correlation of advanced age, smoking, previous major cerebrovascular event (MCVE), and severe coronary artery disease with high grade carotid artery stenosis of 80–99% (p < 0.05). A total of 13 patients had perioperative MCVE and an analysis of risk factors showed that the MCVE correlated with carotid stenosis of > 60% and reduced cardiac output requiring inotropic support (p < 0.01). Prophylactic carotid endarterectomy (CEA) in patients with 80% to 99% carotid stenosis notably decreased the incidence of MCVE (p < 0.01). and the use of the "pump off" technique instead of standard cardiopulmonary bypass decreased MCVE (p = 0.0561. On the basis of these data, prophylactic carotid endarterectomy is effective in averting perioperative MCVE in subjects with carotid stenosis of 80% to 99%. and for those with 6096 to 7996 carotid stenosis, the pump off technique decreases MCVE.  相似文献   
99.
100.

Background

Electrical injuries induce progressive tissue loss caused by free oxygen radicals released from neutrophil aggregates. Fucoidin, a potent inhibitor of L-selectin function, reduces the aggregation of neutrophils. The aim of this study was to evaluate the effect of fucoidin on tissue damage in rat electrical burn injury model.

Methods

Forty-two male Wistar albino rats (250–300 g) were divided into 3 groups (Group A (n = 6), control group without electrical burn injury; Groups B (n = 18) and C (n = 18), electrical burn injury groups without and with fucoidin therapy, respectively). Three separate analyses were performed at different time points on 6 out of 18 mice from Group B and C at each time point. Biochemistry (myeloperoxidase and malondialdehyde levels) and histopathology (number of neutrophils) of the skin and muscle biopsies at 1st hour; tissue edema (ratio of wet weight/dry weight of extremities) at 24th hour; and necrotic areas at 7th day after electrical injury were evaluated. The electrical burn was induced by exposing rats to 220 V AC between their left upper extremity and right lower extremity for 10 s. Fucoidin was administered as 25 mg/kg intravenous bolus injection at 15 min after electrical burn injury.

Results

Myeloperoxidase and malondialdehyde levels, number of neutrophils, tissue edema, and necrotic area were significantly less in fucoidin-applied rats than the group without fucoidin therapy.

Conclusions

Fucoidin inhibits tissue damage induced by electrical burn injury in rats by reducing necrotic area, edema and number of neutrophils.  相似文献   
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