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11.
Extra- and intracellular free iron and the carotid body responses   总被引:3,自引:0,他引:3  
The hypothesis that chelation of free iron, by decreasing reactive oxygen species (ROS), might mimic hypoxia and stimulate the carotid body was tested. We used the iron chelators, desferrioxamine (DFO, 200-400 microM) initially, and later ciclopirox olamine (CPX, 2.5-5.0 microM), on rat carotid body in vitro and measured chemosensory activity and [Ca2+]i in isolated cultured glomus cell clusters during normoxia and hypoxia. Although acute treatment of DFO might not penetrate the cell, and extracellular DFO would not influence these activities whereas CPX significantly increased chemosensory activities as well as increased [Ca2+]i in normoxia. We concluded that chelation of extracellular free iron did not alter ROS formation and oxygen sensing. Chelation of intracellular free iron and, therefore, a decrease in intracellular ROS appears to influence oxygen sensing in the carotid body.  相似文献   
12.
Summary The cancer chemotherapeutic efficacy of dopamine (DA) was evaluated in female strain A mice bearing transplantable Ehrlich ascites carcinoma. The results demonstrated significant inhibition of tumor growth with appreciable increase in the host survival time following DA treatment. Diminished activity of the growth-related respiratory enzyme succinate dehydrogenase along with stimulated activity of the lysosomal enzyme, -glucuronidase in DA-treated tumor cells indicated inhibition of tumor growth as well as active lysis of the tumor cells. The direct effect of this compound on tumor proliferation was demonstrated by marked inhibition of DNA synthesis. RNA synthesis was only marginally inhibited.Abbreviations DA Dopamine - EAC Ehrlich ascites carcinoma - SDH Succinate dehydrogenase - -Glu -glueuronidase - ILS Increase of life span  相似文献   
13.
In the context of collateral circulation of the heart, the role of extra-cardiac collateral arteries has been thought to be negligible. We present a case in which such collateral vessel acted as a rescue, subsequent to a failed revascularisation attempt. With surgeons nowadays considering ‘less is more’ in terms of grafting in coronary artery bypass grafting (CABG), and more evidence arising in favour of medical therapy, we need to re-assess the role of these collateral vessels in the coronary circulation.  相似文献   
14.
The study aim was to determine the extent of malnutrition among young children in an urban Muslim slum community in India in 1986. The sample included 103 families and 88 children 0-5 years old. 57.95% of the children were undernourished: 40.91% at Grade I, 14.77% at Grade II, and 2.27% at Grade III. 75% of infants were undernourished. The relationship between age and nutritional status was not statistically significant, but the association between sex and nutritional status was significant. 68.88% of females and 46.53% of males were undernourished. 64.71% of the undernourished and 51.35% of the nourished had illiterate parents. 70% of children with 3 or more siblings and 58.85% of children with less than 3 siblings were undernourished. 41.18% of the undernourished had upper respiratory tract infections, 52.82% had diarrhea, and 97.37% had parasitic infections. The respective proportions for nourished children were 59.46%, 40.54%, and 78.57%. Statistically significant differences occurred only for parasitic infections.  相似文献   
15.
It has been well documented that it is not uncommon for a thallium-201 perfusion defect to develop or become more evident on delayed exercise thallium scintigraphic imaging, as compared with the initial image immediately following stress. The pathophysiology and clinical significance of the phenomenon are currently unclear. Literature on this subject is reviewed, and it is concluded that reverse redistribution of 201Tl in the post-myocardial infarction patient is indeed a fact. In this context it represents a low-risk condition and may imply successful thrombolysis, patent infarct-related coronary artery, improved wall motion at the infarct site and retained myocardial viability in that segment. Correspondence to: A. Labiri  相似文献   
16.
A new, miniature cesium iodide/photodiode nuclear probe (the "Cardioscint") has been developed for continuous on-line measurement of left ventricular function and the ST-segment. Ejection fraction (EF) measurements in 77 patients were compared with gated equilibrium radionuclide ventriculograms. The probe was positioned over the left ventricle by first using a blind positioning algorithm and then by using the gamma camera. Background was measured both manually and automatically. There was good correlation between probe (positioned blind) and gamma camera EF with both manual (r = 0.80, n = 65) and automatic (r = 0.78, n = 66) backgrounds. Use of the gamma camera did not significantly alter the results. Correlation between the probe stroke counts and thermodilution-derived stroke index during atrial pacing in six subjects was also satisfactory (r = 0.69, n = 102). Thus, the Cardioscint is able to provide a reliable estimate of EF and can track rapid changes in cardiac volumes.  相似文献   
17.
Hamartomas are tumour like malformations which are due to a developmental anomaly. They are most commonly seen in the spleen, lungs, liver and kidney, they are rare in the head and neck region. A rare case of Hamartoma of the soft tissues of the face in a 13 year old boy is reported.  相似文献   
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Onychomycosis is the most common infection of the toe-nails or finger-nails and it may be caused by a large variety of fungal species. Achaetomium species which belong to the phylum Ascomycota (Family Chaetomiaceae), are usually soil saprophytes or endophytic fungi which have been rarely reported as human or animal pathogens. Here, we report a case of onychomycosis caused by Achaetomium strumarium in a healthy person who showed involvement of all fingers of both hands with yellowish brown discoloration. The causative agent isolated was identified as Achaetomium species by morphology, colony morphometry and growth at high temperature and as A. strumarium from DNA sequence of ITS region. Onychomycosis from this case responded satisfactorily with per os (P. O.; oral) and topical application of Terbinafine.  相似文献   
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