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121.
The effect of the fruit essential oil of Cuminum cyminum Linn. (Apiaceae) (syn. Cuminum odorum Salisb) on the epileptiform activity induced by pentylenetetrazol (PTZ) was evaluated, using intracellular technique. The results demonstrated that extracellular application of the essential oil of Cuminum cyminum (1% and 3%) dramatically decreased the frequency of spontaneous activity induced by PTZ in a time and concentration dependent manner. In addition it showed protection against pentylenetetrazol-induced epileptic activity by increasing the duration, decreasing the amplitude of after hyperpolarization potential (AHP) following the action potential, the peak of action potential, and inhibition of the firing rate. These membrane effects suggest cellular mechanisms by which the essential oil of Cuminum cyminum can inhibit the PTZ-induced epileptic activity.  相似文献   
122.
Changes in vascular responsiveness are the basis for some of the cardiovascular complications in cholestasis. Since the duration of cholestasis is important in determining the degree of the complications, we investigated the time-course dependent evolution of vascular relaxation responsiveness in the aortic rings of cholestatic rats. Acetylcholine-induced endothelium-dependent relaxation was investigated in the isolated aortic rings of unoperated, sham-operated and two-, five-, seven- and fourteen-day bile-duct ligated rats. There was a significant reduction in acetylcholine-induced relaxation of the aortic rings by the second day after the bile-duct ligation operation, compared to those of unoperated and sham-operated groups, but more reduction still occurs in 5- and 7-day bile-duct ligated groups, reaching a plateau by the seventh day. The relaxation response to sodium nitroprusside in the aortic rings of the unoperated and the 7-day bile-duct ligated rats did not differ, implying the intact smooth muscle component of the relaxation pathway. L-NAME ( N(omega)-nitro-L-arginine methyl ester), a nitric oxide (NO) synthase inhibitor, attenuated the acetylcholine-induced relaxation in both groups (unoperated and bile-duct ligated), while L-arginine prevents this inhibitory effect. Indomethacin potentiated the acetylcholine-induced relaxation in the aortic rings of the bile-duct ligated rats while it has no effect on unoperated controls, providing evidence for the possible role of vasoconstrictor prostanoids in cholestasis-induced reduction in acetylcholine-induced relaxation. These results state that the reduced acetylcholine-induced relaxation in the cholestatic aortic rings during the first week, when no portal hypertension was reported to be present, may be due to the decreased acetylcholine-induced NO release from endothelium or increased NO inactivation.  相似文献   
123.
BACKGROUND: Acne is generally recognized as a disorder of young adults; however, the referral of patients aged over 25 years with acne is increasing. Disturbed androgen production in the ovaries or adrenal gland and impaired plasma transport of androgens in women with adult-onset acne or acne associated with hirsutism have been described. METHODS: Thirty-five white women with adult-onset acne (onset after the age of 25 years) and hirsutism (A + H), 35 white women with adult acne without hirsutism (A - H), and 35 age-matched white female controls were recruited in this case-control study. Serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone, dihydroepiandrosterone sulfate (DHEA-S), and sex hormone binding globulin (SHBG) were determined in all patients and compared. RESULTS: The mean SHBG, free androgen index (FAI), and DHEA-S were significantly different between A + H and control subjects. The only significant difference between A - H and control subjects was observed for DHEA-S. CONCLUSION: DHEA-S plays a key role in the pathogenesis of adult-onset acne. Measurement of circulating androgens, including DHEA-S, especially in patients presenting with adult-onset acne and hirsutism, is helpful, and patients with elevated levels can benefit from hormonal therapy.  相似文献   
124.
Pimecrolimus cream in repigmentation of vitiligo   总被引:2,自引:0,他引:2  
BACKGROUND: Vitiligo is a chronic disease that mostly affects children and young adults. Nowadays many treatment options are available; however, most of them have limited efficacy and in most cases would result in undesirable complications. OBJECTIVE: To determine the extent of repigmentation according to the location of the lesions after applying topical cream pimecrolimus 1% in vitiligo patients. MATERIALS AND METHODS: Thirty consecutive patients with vitiligo lesions affecting less than 20% of body surface area without any previous history of spontaneous repigmentation were treated with pimecrolimus cream 1% twice daily for 12 weeks. The extent of repigmentation in vitiligo lesions was determined in each patient after 6 and 12 weeks. RESULTS: Moderate to excellent response (repigmentation >26%) was observed in 6.6 and 25.9% of vitiligo lesions 6 and 12 weeks after treatment, respectively. More responsive lesions were located on the trunk, face and elbow (85.7, 75 and 70%). CONCLUSION: Pimecrolimus cream 1% results in repigmentation in vitiligo in different extents according to the location of the lesion; however, to clearly prove its efficacy as monotherapy or in combination with other available treatment options, double-blind placebo-controlled studies are essential.  相似文献   
125.
In recent years researchers have found that alternations in arterial or venular tree of the retinal vasculature are associated with several public health problems such as diabetic retinopathy which is also the leading cause of blindness in the world. A prerequisite for automated assessment of subtle changes in arteries and veins, is to accurately separate those vessels from each other. This is a difficult task due to high similarity between arteries and veins in addition to variation of color and non-uniform illumination inter and intra retinal images. In this paper a novel structural and automated method is presented for artery/vein classification of blood vessels in retinal images. The proposed method consists of three main steps. In the first step, several image enhancement techniques are employed to improve the images. Then a specific feature extraction process is applied to separate major arteries from veins. Indeed, vessels are divided to smaller segments and feature extraction and vessel classification are applied to each small vessel segment instead of each vessel point. Finally, a post processing step is added to improve the results obtained from the previous step using structural characteristics of the retinal vascular network. In the last stage, vessel features at intersection and bifurcation points are processed for detection of arterial and venular sub trees. Ultimately vessel labels are revised by publishing the dominant label through each identified connected tree of arteries or veins. Evaluation of the proposed approach against two different datasets of retinal images including DRIVE database demonstrates the good performance and robustness of the method. The proposed method may be used for determination of arteriolar to venular diameter ratio in retinal images. Also the proposed method potentially allows for further investigation of labels of thinner arteries and veins which might be found by tracing them back to the major vessels.  相似文献   
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128.
Nickel compounds possess many applications in different industrial processes. Human beings are exposed to nickel commonly through occupational exposure and food. Although a few studies so far have investigated the effects of nickel compounds on human lymphocytes, the complete mechanism of cytotoxicity of this metal on human lymphocytes is yet to be determined. The intention of this paper was to determine the cytotoxicity mechanism of water soluble NiCl2 toward human lymphocytes using the accelerated cytotoxicity mechanisms screening (ACMS) technique. Human lymphocytes were isolated from the blood of healthy subjects based on Ficoll-Paque PLUS standard method. For the assessment of cell viability, lymphocytes were incubated with 0.05–1?mM NiCl2 for 12?h. Determination of mechanistic parameters was performed 2, 4 and 6?h after treatment of cells with ½ EC5012h, EC5012h and 2EC5012h of NiCl2. Our results demonstrate that cytotoxicity of NiCl2 on human lymphocytes is associated with increased ROS formation, mitochondrial membrane potential collapse, glutathione depletion, lysosomal membrane damage, cellular proteolysis and activation of caspase-3 before cytotoxicity ensued.  相似文献   
129.
Objective Scorpion (Hemiscorpius lepturus) stings are a public health concern in Iran, particularly in south and southwestern regions of Iran. The gold standard for the treatment of a scorpion sting is anti-venom therapy. However, immunotherapy can have serious side effects, such as anaphylactic shock (which can sometimes even lead to death). The aim of the current study was to demonstrate the protective effect of ozone against toxicity induced by Hemiscorpius lepturus (H. lepturus) venom in mice. Methods Eight hours after the injection of ozone to the experimental design groups, the male mice were decapitated and mitochondria were isolated from five different tissues (liver, kidney, heart, brain, and spinal cord) using differential ultracentrifugation. Then, assessment of mitochondrial parameters including mitochondrial reactive oxidative species (ROS) production, mitochondrial membrane potential (MMP), ATP level, and the release of cytochrome c from the mitochondria was performed. Results Our results showed that H. lepturus venom-induced oxidative stress is related to ROS production and MMP collapse, which is correlated with cytochrome c release and ATP depletion, indicating the predisposition to the cell death signaling. Conclusion In general, ozone therapy in moderate dose can be considered as clinically effective for the treatment of H. lepturus sting as a protective and antioxidant agent.  相似文献   
130.
Stereotactic ablative body radiotherapy (SABR) for primary renal cell carcinoma (RCC) targets requires motion management strategies to verify dose delivery. This case study highlights the effect of a change in patient breathing amplitude on the dosimetry to organs at risk and target structures. A 73-year-old male patient was planned for receiving 26 Gy of radiation in 1 fraction of SABR for a left primary RCC. The patient was simulated with four-dimensional computed tomography (4DCT) and the tumor internal target volume (ITV) was delineated using the 4DCT maximum intensity projection. However, the initially planned treatment was abandoned at the radiation oncologist's discretion after pretreatment cone-beam CT (CBCT) motion verification identified a greater than 50% reduction in superior to inferior diaphragm motion as compared with the planning 4DCT. This patient was resimulated with respiratory coaching instructions. To assess the effect of the change in breathing on the dosimetry to the target, each plan was recalculated on the data set representing the change in breathing condition. A change from smaller to larger breathing showed a 46% loss in planning target volume (PTV) coverage, whereas a change from larger breathing to smaller breathing resulted in an 8% decrease in PTV coverage. ITV coverage was similarly reduced by 8% in both scenarios. This case study highlights the importance of tools to verify breathing motion prior to treatment delivery. 4D image guided radiation therapy verification strategies should focus on not only verifying ITV margin coverage but also the effect on the surrounding organs at risk.  相似文献   
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