Vol.13,

Natural radionuclides in the phosphate rock samples collected from Wadi Batur, Wadi Hegaza and Gabal Abu Had at Eastern Desert were determined using a high resolution γ-ray spectrometer. The experimental results concerning ²²⁶Ra, ²³²Th and their daughters are presented. Analyses of the measured spectra show that ²²⁶Ra is distinguished with remarkable activities with average values ranging from 22.4 to 558 Bq/kg, while ²³²Th activity concentration is in the range of 9.7 to 92.8 Bq/kg. The results of the analyses were found to be in a good agreement with the data obtained by others.

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Thin calcium phosphate coatings on titanium alloy substrates were prepared by Ar⁺ ion beam assisted deposition (IBAD) from hydroxyl-poly-calcium sodium phosphate (HPPA) target. The coatings were analyzed by XRD, FTIR, XPS. These analyses revealed that the as-deposited films were amorphous or no apparent crystallinity. No distinct absorption band of the hydroxyl group was observed in FTIR, spectra of the coatings but new absorption bands were presented for CO 3 -2 . The calcium to phosphorous ratio of these coatings in different IBAD conditions varied from 0.46 to 3.36.

350

The aim of the study was to demonstrate the degeneration of the dopaninergic nigrostriatal pathway in Parkinson's disease(PD) and Essential Tremor (ET) by using the cocaine derivative ^99mTc-TRODAT-1 SPECT and correlate the findings to the clinical severities (Hoehn and Yahr scale, H/Y). 28 patients with idiopathic Parkinson's disease, 10 patients with Essential Tremor and 19 healthy volunteers were investigated. The acquisition were performed 3h postinjection of ^99mTc-TRODAT-1, ROIs were drawn over the images of striatum and cerebellum, and ratios of striatum to cerebellar(ST/CB) were calculated. Ratios differed significantly between PD and controls, but ratios didn't show significant difference between ET patients and controls. A significant correlation didn't exist between ratios and clinical severities. Hemiparkinson's patients revealed significantly diminished ^99mTc-TRODAT-1 binding not only clinically affected but unaffected side. Our findings indicated that ^99mTc-TRODAT-1 SPECT is not only a reliable method to discriminate between PD and controls but also a useful tool for differential diagnosis in clinically unclear cases such as ET resembling PD.

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This study aims at the theoretical and practical evidence for prevention of restenosis in vitro. Vascular smooth muscle cell (VSMC) model was established using adherent cell culture methods. The proliferation of VSMC was investigated by the cell counting method and ³H-TDR implementation test. The results are as follows. (1) For ¹²⁵I-seeds, the inhibition rate was 29.3% at 74Bq (p<0.05), 35.2% at 148Bq (p<0.05) and 42.4% at 370Bq (p<0.05), For ¹⁰³Pd-implanted stents, the inhibition rate was 14.7% at 4.44 MBq (p<0.05), 24.0% at 5.92 MBq (p<0.05) and 38.0% at 7.4 MBq (p<0.05), There was no significant difference between the blank tests and non-radioactive tests. (2) 48 hours exposure from ¹²⁵I-seeds at 148 Bq or ¹⁰³Pd-implanted stents at 7.4 MBq did not result in VSMC's morphological alteration, but that from ¹²⁵I-seeds at 370Bq caused morphological changes, Both ¹²⁵I-seeds and ¹⁰³Pd-implanted stents inhibit the VSMC DNA synthesis in vitro. The inhibition effects are significantly related to their exposure duration and doses.

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In order to investigate the therapeutic mechanisms of acupuncture points in cerebrovascular ischemic patients and normal volunteers, FDG PET was adopted. Changes in cerebral glucose metabolism and cerebral functional activity before and after electro-acupuncture treatment were studied in 12 normal volunteers and 11 cerebrovascular ischernic patients. The PET imaging was read by visual interpretation and calculated by semi-quantitative analysis. After acupuncture, cerebral glucose metabolism of the normal group is higher in the frontal lobe, temporal lobe, thalamus bilaterally and cerebellum contralaterally. The cerebrovascular ischemic patients had manifested greater response in their lesions than in their normal regions of the two tested groups, as well as than in their normal regions of the whole brain, after acupuncture treatment. The study shows that the regulatory effects of acupuncture on the central nervous system influence the brain at multiple-sections, multiple-directions and multiple-levels of brain function. Itconforms to the holistic and bi-directions regulatory laws of acupuncture.

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In order to study the effects of every part of adrenergic receptor-adenyl cyclase system on ischemic preconditioning of myocrdium in rats in vivo, SD rats were divided into three groups: IP group, I/R group and CON group. Rats were received surgical procedure and undergone left coronary artery occlusion and reperfusion. Hearts were extracted to analyze the infarct size by TTC staining, to measure serum myocardial enzymes, to study β-AR Bmax and Kd by radioligand binding assay of receptors (RAB), and to check the activity of AC and the content of cAMP by radioimmunoassay (RIA). The infarct area was found much smaller in IP group than I/R group (p<0.001); CK,CK MB and LDH were found significantly higher in I/R group (p<0.001), The Bmax of β-A R in IP group were higher than in I/R group (p<0.001), No difference of Kd could be seen between IP and I/R group, In IP group, the activity of Ac and the content of cAMP were higher than I/R group (p<0.05 and 0.001, respectively). It is concluded that ischemic preconditioning can protect the hearts from necrosis and reduce endo-enzyme leakage. The system of adrenergic receptor-adenyl cyclase system probably takes part in the protection of the IP.

429

Chelation of ¹⁸⁸Re to compounds such as MAG₃ will further reduce the radiation dose to the patient in case of balloon rupture through the rapid excretion from the body. In order to prepare highly concentrated, carrier free ¹⁸⁸Re-MAG₃, Sbenzoyl mercaptoacetyltriglycine (S-Bz-MAG₃) was synthesized, labeled with carrier free ¹⁸⁸Re, The overall yield of S-Bz-MAG₃ is higher than those published in the literature. Dependence of the labeling yield of ¹⁸⁸Re-MAG₃ upon concentrations of reducing agent, pH, reaction time, etc. was examined and optimum conditions were confirmed. The concentration procedure was succeeded with Sep-Pak C18 cartridge to obtain highly concentrated ¹⁸⁸Re-MAG₃. In the case of optimun conditions, the labeling yield of ¹⁸⁸Re-MAG₃ was more than 98%. Radiochemical purity of ¹⁸⁸Re-MAG₃ was more than 92% after 24 hour storage at room temperature.

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No-carrier-added 6-[¹⁸F] fluoro-L-DOPA (6-FDOPA) was synthesized via a multistep procedure from a commercial available precursor, 6-nitroveratraldehyde, The total synthesis time was 75min, with a radiochemical yield of (10±3)%, high radiochemical purity (>99%) and high enantiomeric purity (>95%) The biodistributions of 6-FDOPA in normal and unilateral PD model rats were measured. The results from normal rats showed the expected high concentration of radioactivity in striatum and low distributions in cerebrum, cortex and cerebellum. The ratio of the radioactivity in striatum to cerebellum reached a peak value (5.9) at 60 min. In unilateral PD model rats, whose substania nigra of the right side had been damaged by pre-treated with 6-OHDA, the radioactive concentration in striatum of the damaged side was significantly lower than that of the undamaged side or that of both sides in striatum of control groups.

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An improved CBB staining with higher sensitivity than that of the typical CBB staining was reported. The main improvement was using a fixing step of 25% trichloroacetic acid (TCA) before CBB staining. For most proteins studied, the sensitivity of the improved CBB staining was about twice as high as that of the typical method. For basic and low molecular weight proteins such as ribosomal proteins, the sensitivity of this improved staining method was about 3.5-28 times that of the typical method. It was speculated that the improved procedure would be suitable for exact quantitative analysis of proteins fractionated by SDS-PAGE, especially for basic and low molecular weight proteins. On the other hand, this new modified method might be also applied to multidisciplinary studies, such as biological researches and nuclear sciences.

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Survival curves of Chinese hamster V79 cells exposed to accelerated carbon ions with linear energy transfers of 125.5, 200 and 700 keV/μm were measured, respectively. Inactivation cross sections corresponding to the irradiation above were deduced from the V79 cell survival curves. They are 7.86±0.17, 10.44±1.11 and 32.32±3.58μm² in turn. With the surviving response of V79 cells to ⁶⁰Co γ-rays as a reference value, relative biological effectiveness at 10%, 20%, 50% and 80% survival levels were given for the accelerated carbon ions. The results showed that carbon ions with LET of 125.5 keV/μm had a higher value of RBE at all the four survival levels than the carbon ions with other LETs. It was prompted that the maximum value of RBE for the V79 cell surviving as the biological endpoint emerged at the LET below 200 keV/μm for carbon ions.

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