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991.
以2-硝基-4-甲氧基-5-溴乙酰苯胺为原料,经6步反应,合成了7个4-甲基-5-取代苯氧基伯氨喹类似物(Ⅱ2~8)。抗疟活性的初步评价结果表明,这类化合物对鼠疟 Plasmodium yoelii 的病因性预防作用明显优于伯氨喹.可达伯氨唪的4~8倍;同时,Ⅱ2~8还有较强的杀血液裂殖体作用.Ⅱ2,5,6,8在0.781 mg·kg-1 的剂量对原虫的抑制率为100%。  相似文献   
992.
Idiopathic acute transverse myelitis: MR imaging findings   总被引:3,自引:0,他引:3  
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993.
994.
The author explores the costs and impact of capital punishment on society's ability to address social ills that precede criminal behavior–lack of access to health care, child abuse, domestic violence, drug addictions, and poverty. Two case studies are used to demonstrate that the death penalty is applied arbitrarily against the disadvantaged, the mentally ill, and the retarded. The author asserts that nurses must not support killing people, and challenges nurses to find ways to address community health issues to provide alternatives to capital punishment.  相似文献   
995.
996.
In the Western world, chronic inflammatory bowel disease (IBD) presents as two major clinical forms, Crohn's disease (CD) and ulcerative colitis (UC) [Targan, S.R. and Shanahan, F. (1994). In Retford, D.C (ed.), Inflammatory Bowel Disease: From Bench to Bedside. Williams and Wilkins, Baltimore]. Genetic epidemiological studies, the occurrence of rare syndromes associated with IBD, and animal models suggest that inherited factors play significant roles in the susceptibility to both forms of IBD [Yang, H.-Y. and Rotter, J.I. (1995) In Kirsner, J.B. and Shorter, R.G. (eds). Genetic Aspects of Idiopathic Inflammatory Bowel Disease. Williams and Wilkins, Baltimore, pp.301-331]. Recently, a genome-wide search on European families with multiple affected members with CD identified a putative susceptibility locus in the centromeric region of chromosome 16 [Hugot, J.-P. et al. (1996) Nature, 379, 821- 823]. We have now tested this region in an independent set of US families, confirmed that this region is likely to contain a gene predisposing to CD, and further refined the chromosomal location of this gene. Most importantly with respect to this locus, our data also seem to indicate that there is heterogeneity both within the CD group, and between the CD and UC groups with respect to this locus. The susceptibility locus appears to be involved only in non-Jewish CD sibpairs and not in our Ashkenazi Jewish CD sibpairs. Additionally, we have tested sibpairs having either only UC or both UC and CD for involvement of this locus, and have found no evidence that this region predisposes to IBD in these patients.   相似文献   
997.
In this study we demonstrated that a hemolytic strain of Listeria monocytogenes, but not a nonhemolytic mutant derived from it, translocated in substantial numbers to the mesenteric lymph nodes, spleen, and liver after intragastric inoculation of mice. Growth at 4 degrees C prior to inoculation did not increase the virulence of the nonhemolytic mutant. These results indicate that hemolytic activity is required for the virulence of L. monocytogenes via the gastrointestinal tract, as has been shown previously for parenteral challenge.  相似文献   
998.
Within the scope of an observation study 40 premature low birth weight infants requiring parenteral nutrition received either 10% or 20% lipid emulsions (Lipoven?s) for 7 days. The 10% lipid emulsion differs from the 20% lipid emulsion in the higher phospholipid/triglyceride-ratio (0.06 resp. 0.12). Lipid infusion was commenced at 0.5 g triglyceride/kg/24 hours and increased steadily to 2 g triglyceride/kg/24 hours. The aim of the study was to compare the effects of the two intravenously administered lipid emulsions on serum clearance. The serum concentrations of triglyceride and cholesterol did not change significantly during the infusion with 20% Lipoven?s. Significant increases in the triglyceride and cholesterol content were observed only in the serum of the patients who were given the 10% Lipoven?s. The reduced lipid serum clearance is attributable to the higher content of phospholipids in the 10% lipid emulsion. With regard to the risk of high cholesterol concentrations and an abnormal LPX serum accumulation, administration of 20% lipid emulsion is preferable to 10% lipid emulsion, also during the neonatal period.  相似文献   
999.
1000.
Adult T-cell leukemia (ATL) is a malignancy of mature lymphocytes caused by the retrovirus human T-cell lymphotrophic virus-I (HTLV-I). It is an aggressive leukemia with an overall mortality rate of 50% within 5 months; no conventional chemotherapy regimen appears successful in inducing long-term disease-free survival in ATL patients. However, ATL cells constitutively express high-affinity interleukin-2 receptors (IL-2Rs) identified by the anti-Tac monoclonal antibody, whereas normal resting cells do not. To exploit this difference in receptor expression, we administered anti-Tac intravenously (IV) to 19 patients with ATL. In general the patients did not suffer untoward reactions, and in 18 of 19 cases did not have a reduction in normal formed elements of the blood. Seven patients developed remissions that were mixed (1 patient), partial (4 patients), or complete (2 patients), with partial and complete remissions lasting from 9 weeks to more than 3 years as assessed by routine hematologic tests, immunofluorescence analysis, and molecular genetic analysis of T-cell receptor gene rearrangements and of HTLV-I proviral integration. Furthermore, remission was associated with a return to normal serum calcium levels and an improvement of liver function tests. Remission was also associated in some cases with an amelioration of the profound immunodeficiency state that characterizes ATL. Thus the use of a monoclonal antibody that blocks the interaction of IL-2 with its receptor expressed on ATL cells provides a rational approach for treatment of this aggressive malignancy.  相似文献   
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