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61.
62.
MH Mullerworth P Angelopoulos MA Couyant AM Horton SM Robinson OU Petring PJ Mitchell JJ Presneill 《Canadian Metallurgical Quarterly》1998,66(4):1242-1245
The use of PCR to amplify a specific virA gene fragment serves as a highly specific and sensitive method to detect virulent bacteria of the genus Shigella and enteroinvasive Escherichia coli. Amplification of a 215-bp DNA band was obtained by using isolated genomic DNA of Shigella, individual cells of Shigella dysenteriae, and mayonnaise contaminated with S. dysenteriae. Moreover, a multiplex PCR with specific (virA) and bacterium-restricted (16S ribosomal DNA) primers generated an amplification product of approximately 755 bp for all bacteria tested and an additional 215-bp product for Shigella and enteroinvasive E. coli. 相似文献
63.
J Avorn M Monane DE Everitt MH Beers D Fields 《Canadian Metallurgical Quarterly》1994,154(10):1113-1117
BACKGROUND: We sought to quantify the relationship between antipsychotic drug use and clinical evidence of extrapyramidal dysfunction in a large population of elderly nursing home patients. METHODS: Subjects were 251 residents (mean age, 84.1 years; range, 65 to 105 years) who were taking psychoactive drugs in 12 long-term care facilities. Patient characteristics and all medication use (both scheduled and as needed) were measured during a 1-month observation period. We then performed neuropsychological and functional testing on residents who received any psychoactive medications during the study month. The presence of rigidity, bradykinesia, or masklike facies was assessed in each patient by a research assistant who was unaware of diagnoses and medication use. RESULTS: The parkinsonian signs studied were found in 127 (50.6%) of these residents. Using logistic regression modeling to adjust for potential confounding, we found this outcome to be increased more than threefold in patients who took low-potency neuroleptics (odds ratio [OR], 3.49 for > or = 50 mg/d of chlorpromazine-type drugs; 95% confidence interval [CI], 1.28 to 9.57) and more than sixfold for use of 1 mg/d or more of haloperidol (OR, 6.42; 95% CI, 2.16 to 19.04). Age, gender, and use of nonneuroleptic psychoactive drugs were not associated with an increase in parkinsonian signs. CONCLUSIONS: Clinical evidence of extrapyramidal dysfunction is three to six times more common in institutionalized elderly patients given antipsychotic medication than in comparable patients not using such drugs. Its risk is substantially increased even in patients given low-potency chlorpromazine-type drugs, as well as those taking haloperidol. The effect is not explained by age or mental status and is not seen with other psychoactive medications. The expected frequency of parkinsonian symptoms can help to inform the balancing of risks vs therapeutic effect when the use of all drugs in this class is considered. 相似文献
64.
A K?se MH Johansson MY Olsson-Alheim K K?rre P H?glund 《Canadian Metallurgical Quarterly》1998,161(11):6133-6138
Expression of the H-2Dd-specific inhibitory receptor Ly49A on murine NK cells is subject to MHC class I-dependent modulation in vivo. As a result, NK cells in H-2Dd-transgenic mice express low cell surface levels of Ly49A, whereas NK cells from nontransgenic C57BL/6 (B6) mice express high levels. The purpose of this study was to assess the role of MHC class I molecules on the NK cell itself vs those on surrounding cells in this calibration and to test whether the Ly49A levels are subject to regulation in mature NK cells also. Analysis of transgenic mice with mosaic expression of an H-2Dd/Ld transgene showed that MHC class I molecules on surrounding cells (external ligands) and on the NK cell itself (internal ligands) played distinct roles in the determination of Ly49A levels. External ligands were involved in down-regulation of Ly49A levels in vivo, whereas internal ligands kept the down-regulated levels of Ly49A low upon NK cell activation in vitro. Furthermore, in an experimental system based on adoptive transfer of spleen cells, receptor down-regulation of Ly49A occurred as a rapid adaptation process in mature NK cells after interaction with the H-2Dd ligand in vivo. This suggests that Ly49 levels are not fixed but can be changed in mature NK cells when they are exposed to a changed MHC class I environment. 相似文献
65.
BACKGROUND: Orthostatic hypotension is a common phenomenon in the elderly. Hormonal changes during orthostatic stress have been described in elderly normotensive people and in those with essential hypertension. However, the hormonal response in elderly people who have systolic hypertension during orthostasis has not yet been quantified. METHODS: In this study we investigated 14 non-diabetic men, aged 60 to 75 years, with untreated systolic hypertension who were subjected to 45 degrees passive head-up incline on a tilt table for 15 min. Their hormonal profile and hemodynamic changes were analyzed before and after the stress. RESULTS: In the supine position, plasma levels of norepinephrine, atrial natriuretic peptide and aldosterone were in the normal range, while the plasma renin activity was low. Immediately upon tilt the systolic blood pressure fell but it reverted to baseline values after 15 min of orthostasis. At that time the cardiac output decreased while the systemic vascular resistance and the plasma norepinephrine concentration rose. The atrial natriuretic peptide appeared to fall, and the renin-aldosterone level did not change. CONCLUSION: The physiologic response to orthostatic stress in elderly people with systolic hypertension is comparable to that of elderly normotensive people and those with essential hypertension, i.e. a decrease in cardiac output and an increase in plasma norepinephrine levels. The atrial natriuretic peptide appeared to fall appropriately. The response of the renin-aldosterone system mimicked that in elderly patients with low renin essential isolated hypertension. These observations may have a bearing on the management of elderly people with systolic hypertension who also have orthostatic symptoms; they may not require a different approach from that needed for others of the same age group. 相似文献
66.
Chronic myopathy is a common complication of alcoholism, but its natural history has not been well described. We, therefore, studied muscle structure and function in a 5-year study of 30 chronic alcoholics who became abstinent and 20 who relapsed, and 40 control subjects. The mean strength of the abstaining alcoholics increased from 18.6 to 23.2 kg; but, after 5 years, they were still substantially weaker than controls. In a subset who showed histological myopathy, the strength of half of the patients remained two standard deviations below that of controls. Alcoholics who relapsed tended to become progressively weaker (21.7 kg vs. 18.2 kg) and develop histological evidence of myopathy. Thus, continued alcohol abuse was generally reflected in deterioration of muscle strength and the appearance of histological injury to muscle. Importantly, almost half of the sober patients did not recover to normal levels, indicating that alcoholic myopathy is only partially reversible. We also unexpectedly found that, in some alcoholics, a substantial reduction in the amount of alcohol consumed may be as effective as complete abstinence in improving muscle strength or preventing its deterioration. 相似文献
67.
The clinical fertility tests, available in the market, fail to define the exact cause of male infertility in almost half of the cases and point toward a crucial need of developing better ways of infertility investigations. The protein biomarkers may help us toward better understanding of unknown cases of male infertility that, in turn, can guide us to find better therapeutic solutions. Many clinical attempts have been made to identify biomarkers of male infertility in sperm proteome but only few studies have targeted seminal plasma. Human seminal plasma is a rich source of proteins that are essentially required for development of sperm and successful fertilization. This viewpoint article highlights the importance of human seminal plasma proteome in reproductive physiology and suggests that differential proteomics integrated with functional analysis may help us in searching potential biomarkers of male infertility. 相似文献
68.
Anil Kumar William R. Leo Lawrence Green Gene L. Woodruff 《Journal of Fusion Energy》1989,8(1-2):107-126
The neutron spectra transmitted across a fission-suppressed hybrid blanket and its components, driven by a low intensity 14 MeV Haefely neutron generator, were measured with a 2×2 NE213 detector at LOTUS facility. These experiments have been analyzed with 2D and 3D codes DOT3.5 and MCNP, respectively. The spectral integrals between 15 to 1 MeV show good agreement among the 2D, the 3D, and the NE213 for 15 cm lead, 18 cm beryllium, and 25 cm graphite slabs. However, there are large discrepancies for 6.2 cm stainless steel and 15 cm lithium carbonate slabs. The assemblies involving two or more of these slabs reflect these tendencies. We observe also considerable disagreement over pointwise spectra for a number of assemblies.Work done while on visiting assignment to Institut de Génie Atomique, E.P.F.L. 相似文献
69.
Viscosity data over a temperature range of 37-115°C and a pressure range of 0-10 MPa gauge are presented for a Cold Lake bitumen sample. These data show that the compression of Cold Lake bitumen results in a significant increase in its viscosity. Results are compared with those from a similar study on an Athabasca bitumen sample. Also presented are two correlations for the effects of pressure and temperature on the viscosity of Cold Lake bitumen. 相似文献
70.
A predictive model was developed for the fully developed zone of a circulating fluidized bed (CFB) riser reactor operating in the fast fluidization regime that overcomes limitations of existing models. The model accounts for the upward flow of gas and solids in the core and downward flow of the two phases in the annulus. Additionally, a numerical solution methodology for the simulation of a riser reactor employing the hydrodynamic model was devised. A simulation was performed using the fast, main Claus reaction to demonstrate the effects of backmixing in the fast fluidization regime. It was found that the molar flow rates of the reactants leaving a fast fluidized CFB riser reactor were significantly higher than those leaving an identical reactor operating in the pneumatic transport regime. 相似文献