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1.
Brigden Geoffrey Zanelli Giussepe Lahiri Avijit Raftery Edward 《European journal of nuclear medicine and molecular imaging》1990,16(11):795-799
A new, single bolus method of in vivo blood pool imaging using a technetium Tc99m phosphine isocyanide complex (DEPIC) which binds to pre-albumin was evaluated in volunteers (n=4) and patients (n=20). DEPIC was assessed for its safety and possible drug interactions. Its duration of action and quality of ventriculography were compared with imaging using standard in vivo red cell labelling (PYP) during two 3-h scanning periods 1 week apart. DEPIC had a mean plasma halflife of 3.3 h. The count rate over the left ventricle was initially 42% higher with DEPIC than with PYP. However, removal of DEPIC by the liver resulted in equivalent count rates by 1 h, and by 3 h PYP count rates were 22% higher than DEPIC. Immediately post injection mean (SD) difference in the left ventricular ejection fraction between the two methods was 2.4% (7.7%). Satisfactory DEPIC scans were obtained up to 2 h post injection, but by 3 h there was a mean difference of 13% (11.3%). DEPIC was found to be a safe alternative to red all labelling for blood pool angiography, suitable for routine work. The single bolus methodology and high initial count rates offer improved efficiency and a capability for truly emergency scanning. 相似文献
2.
Prevalence of silent myocardial ischemia in asymptomatic individuals with subclinical atherosclerosis detected by electron beam tomography 总被引:3,自引:0,他引:3
Anand D. Vijay Lim Eric Raval Usha Lipkin David Lahiri Avijit 《Journal of nuclear cardiology》2004,11(4):450-457
BACKGROUND: Electron beam tomography coronary calcium imaging is an evolving technique for the early detection of coronary atherosclerosis, and recent studies have established its prognostic value in asymptomatic individuals. The relationship of coronary artery calcium scores (CAC) to obstructive coronary artery disease (CAD) has been poorly studied but is clinically relevant because it determines which individuals are likely to benefit from revascularization procedures. Hence, we prospectively evaluated the prevalence of myocardial ischemia in asymptomatic patients with cardiovascular risk factors and subclinical atherosclerosis. METHODS AND RESULTS: We studied 864 asymptomatic patients with no previous CAD but with cardiovascular risk factors, referred for electron beam tomography coronary calcium imaging to our institution over an 18-month period. From this group, 220 consecutive patients (85% men; mean age, 61 +/- 9 years; age range, 31-84 years) with moderate to severe atherosclerotic disease (coronary calcium score > or =100 Agatston units) were prospectively evaluated by technetium 99m sestamibi single photon emission computed tomography (SPECT). Patients were followed up (mean follow-up, 14 months) and data regarding their subsequent clinical management recorded. Of the 220 patients, 119 had moderate atherosclerosis (CAC score of 100-400 Agatston units) and 101 had severe atherosclerosis (CAC score > or =400 Agatston units). Abnormal SPECT findings were seen in 18% of patients with moderate atherosclerosis (n = 21) and 45% of patients with severe atherosclerosis (n = 45). Increasing severity of atherosclerosis was related to increasing ischemic burden (summed difference score = 1 +/- 0.2 for CAC score of 100-400 Agatston units and 3.2 +/- 0.5 for CAC score > or =400 Agatston units). In a multivariate linear regression model incorporating risk factors, CAC was the only predictor of silent ischemia. CONCLUSION: In comparison to previously published data, we detected a higher prevalence of silent ischemia even in patients with moderate coronary atherosclerosis (18%). This may reflect the differing risk factor profile of our patient population. When coronary calcium screening is used to preselect asymptomatic patients with cardiovascular risk factors for myocardial perfusion imaging, the optimum coronary calcium score threshold will depend on the population prevalence of risk factors and asymptomatic obstructive CAD. 相似文献
3.
Gallium and thallium radionuclides have both diagnostic and therapeutic applications in the field of nuclear medicine. Poly(N-vinylpyrrolidone) (PVP) is routinely used as a drug base because of its excellent biocompatibility. In this paper, complex formation abilities between no-carrier-added (66,)(67)Ga/(199)Tl radionuclides and PVP have been studied. It has been found that aqueous 5% PVP solution can almost quantitatively back extract (66,)(67)Ga/(199)Tl radionuclides from an organic phase, which proves the complexing ability of PVP with (66,)(67)Ga/(199)Tl. Tl(3+) is more efficient to form Tl-PVP complexes than Tl(+). However, Tl(3+)-PVP complexes are less stable than Ga(3+)-PVP complexes. 相似文献
4.
The responses of the ganglioglomerular nerve (GGN) to transient changes and steady-state levels of paO2 at a constant paCO2 were studied in 12 anesthetized and spontaneously breathing cats before and after bilateral section of aortic (AN) and carotid sinus nerves (CSN). In two of these cats carotid chemoreceptor activity was monitored simultaneously. Onset of moderate hypoxia, down to paO2 of about 50 Torr, stimulated GGN activity and withdrawal of the hypoxic stimulus promptly eliminated the responses both before and after CSN section. CSN section, however, significantly raised the baseline activity and slightly delayed the GGN response to the onset of hypoxia. These responses to hypoxia are qualitatively similar to the characteristic responses of peripheral chemoreceptors. Thus, the basic oxygen chemosensing mechanism appeared to be present in the sympathetic nervous system, and is expressed in the postganglionic GGN activity. This property allows the sympathetic nervous system to perform physiologically important functions independent of the peripheral chemoreceptors. 相似文献
5.
Summary We report two cases of Creutzfeld-Jakob disease with clusters of giant collagen fibers. To our knowledge, these abnormally large collagen fibers have never been described in patients with degenerative diseases of the central nervous system. The significance of the formation of such plaque-like large collagen fibers has as yet not been elucidated. It is felt that these represent a product of the degenerative process.Presented in part at the 68th Annual Meeting of the American Association of Neuropathologists, St. Louis, Missouri, June 18–21, 1992 相似文献
6.
The ST segment of the ambulatory electrocardiogram in a normal population. 总被引:1,自引:1,他引:0 下载免费PDF全文
The behaviour of the ST segment in everyday life was studied by ambulatory electrocardiography in 111 normal volunteers. Fifteen were excluded because of abnormal exercise responses (10 subjects) and significant postural ST segment shifts (five subjects). This left 62 men and 34 women, mean (SD) age 40.5 (12.6) years (range 20-67 years). Ambulatory monitoring of leads CM5 and CC5 for 24 hours was followed by a maximal treadmill exercise test. The tapes of the ambulatory monitoring were analysed by a computer aided system. The computer printed trend plots of the ST segment (measured both at the J point and at J + 60 ms) to detect episodes of ST segment elevation and depression, which were confirmed by visual analysis of real time printouts. Twelve subjects showed "ischaemic" ST segment depression and nine subjects showed ST segment elevation. Eight people with ambulatory ST segment changes were studied during exercise by radionuclide ventriculography and thallium-201 imaging scans. Although seven of the eight thallium studies were normal, radionuclide ventriculography showed functional impairment in five cases. Seven of the 10 subjects with abnormal exercise tests were similarly investigated and their results followed the same pattern, with normal thallium images in six and functional impairment in four. Ambulatory electrocardiography was repeated in 20 people after a median of 20 days. The ST segment changes were reproducible. ST segment changes of an apparently ischaemic nature occur even in a carefully defined normal population but they do not necessarily represent latent clinically significant coronary artery disease. This indicates that ST segment changes seen in patients with known obstructive coronary artery disease should be interpreted with caution. 相似文献
7.
8.
Partha Sarathi Dasgupta Twisha Lahiri 《Journal of cancer research and clinical oncology》1987,113(4):363-368
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
9.
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
10.
Ray SK Roy P Deysarkari S Lahiri A Mukhopadhaya BB 《Indian journal of maternal and child health : official publication of Indian Maternal and Child Health Association,》1990,1(2):61-62
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