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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Development of a high performance zinc-62/copper-62 radionuclide generator for positron emission tomography. 总被引:2,自引:0,他引:2
J Zweit R Goodall M Cox J W Babich G A Potter H L Sharma R J Ott 《European journal of nuclear medicine》1992,19(6):418-425
Clinical utilisation of positron emission tomography could be enhanced by the availability of short-lived radionuclides derived from generator systems. The zinc-62/copper-62 combination is one such system which could be used as a source for a number of copper-62 radiopharmaceuticals. We have developed and optimised a high activity (5.6 GBq, 150 mCi) zinc-62/copper-62 generator to provide 62Cu in a form that is suitable for direct labelling of pyruvaldehyde-bis-(N4-methylthiosemicarbazone)-copper(II), Cu(PTSM). The distribution coefficients of Zn(II) and Cu(II) between anion-exchange resin and various hydrochloric acid/organic solvent mixtures were measured. Based on these measurements a generator eluent of 0.3 M HCl/40% ethanol provided 62Cu in greater than 90% yield in a 3-ml volume. A very low 62Zn breakthrough of less than 3 x 10(-7)% was achieved. Copper-PTSM was successfully labelled with the no-carrier-added 62Cu eluent directly from the generator with 94% radiochemical yield. 相似文献
72.
73.
Deepu Banerji Rajesh Acharya Sanjay Behari Devendra K. Chhabra Dr. Vijendra K. Jain MCh 《Neurosurgical review》1997,20(1):25-31
The choice of a surgical approach for multi-level cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL) is still a controversial issue. While most of the surgeons are still performing decompression by laminectomy some are doing multi-level anterior decompression. Few neurosurgeons are performing decompression by corpectomy. We have treated 26 patients by median cervical corpectomy during the last 4 years. These patients were followed up for a mean period of 25 months. Twenty one (80%) patients had a good outcome, 2 patients remained unchanged and 3 expired. Review of the literature and our experience indicates that patients with CSM and OPLL should be operated by median cervical corpectomy (anterior approach). 相似文献
74.
Water-suppressed 1H magnetic resonance spectra were recorded from two brain regions of psychiatric patients and normal volunteers. The two regions studied were (a) the basal ganglia structures surrounding the anterior horn of the lateral ventricle and (b) the occipital cortex. N-Acetylaspartate (NAA), phosphocreatine-creatine (PCr-Cr), choline and inositol resonances were seen in both regions. Ratios of metabolite peak integrals to PCr-Cr peak integral were calculated for each spectrum. To control for partial volume effects, comparisons between patients and controls were made only from identical regions i.e. basal ganglia vs basal ganglia, and likewise for occipital cortex. Metabolite ratios from the occipital region of patients were similar to those from the occipital region of normal subjects. Bipolar patients being treated with lithium had elevated NAA/PCr-Cr in the basal ganglia region when compared to normals. These patients also demonstrated elevated choline/PCr-Cr and inositol/PCr-Cr ratios in the basal ganglia region. 相似文献
75.
76.
N. C. Sharma R. Bhatia S. Singh P. C. John S. Kumar H. Singh 《Epidemiology and infection》1994,112(1):45-49
A total of 675 strains of Salmonella bareilly received from different parts of India and France during 1959-92 were phage typed using six bacteriophages. Overall typability achieved was 90.8% with 23 distinct phage types excluding a group of untypable strains. Phage types have been defined in octal code. Simpson''s coefficient was applied for diversity index having a value of 0.839. This system was found to be reproducible, stable and epidemiologically useful. 相似文献
77.
A study conducted in 1990 revealed that 2% (range 0.6-4.8) of negative blood smears were mislabelled as positive, and 6.7% of positive blood smears were mislabelled as negative. A result of such mislabelling would be inadequate treatment of a large number of patients. Hence the need to look into the training aspect and system of supervision of laboratory technicians. The present system of cross-checking of blood smears at different levels also needs to be reviewed. A study which could address itself to these needs is indicated. 相似文献
78.
79.
D L Delaware M S Sharma B S Iyengar W A Remers T A Pursiano 《The Journal of antibiotics》1986,39(2):251-258
Dihydrostreptomycin analogues with structural variations in their guanidino groups were prepared. The analogue with a methyl group on the guanidine at C-1 was nearly as active as dihydrostreptomycin against bacteria. However, the 2-imidazolin-2-ylamino substituent at C-1 eliminated activity. No analogue with a substituent on the C-3 guanidino group was active. 相似文献
80.
Yashpaul Sharma S. B. S. Mann R. J. Dash Y. N. Mehra 《Indian journal of otolaryngology and head and neck surgery》1987,39(4):163-166
This study was undertaken to record the Brainstem Evoked Responses in a group of 20 diabetic patients with normal hearing and were compared with responses of another group of 20 normal individuals. Eighth nerve transmission till the level of cochlear nucleus was found to be normal in diabetics. The delay in latency of Wave III, IV and V and interpeak latencies (I–III, I–V) were noted to be statistically significant, thus suggesting the presence of central neuropathy in patients with diabetes. No significant sex difference on latency of waves was observed. 相似文献