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81.
目的:建立血虚和免疫抑制动物模型,观察鸡胚胎低温提取物对其红细胞造血以及免疫器官质量的影响。方法:实验于2001-04/2002-09在新乡医学院药物研究室完成。①实验材料:健康昆明种小鼠50只,雌雄各半。鸡胚胎素[中国发明专利公开(公告)号:CN1748713],符合研究者申报专利时提出的质量检验标准。②鸡胚胎素对血虚模型小鼠红细胞数值及血红蛋白含量的影响:取20只小鼠,随机排列表法分为鸡胚胎素组、模型对照组,10只/组,建立失血性血虚动物模型。失血后24h当红细胞数<3.2×1012L-1、血红蛋白含量<84g/L,且小鼠外观出现皮色苍白、食欲不振等现象时,代表造模成功。次日,鸡胚胎素组给予鸡胚胎素5g/(kg·d)灌胃,模型对照组给予生理盐水20mL/(kg·d)灌胃,连续14d。分别于失血前、失血后24h、末次给鸡胚胎素后2h尾部采血测定两组红细胞数量及血红蛋白含量的变化。③鸡胚胎素对免疫抑制模型小鼠免疫器官质量的影响:取30只小鼠,随机排列表法分为鸡胚胎素组、模型对照组、正常对照组,10只/组。鸡胚胎素组给予鸡胚胎素5g/(kg·d)灌胃,模型对照组和正常对照组均灌服等量生理盐水,连续14d。在第11天上午鸡胚胎素灌胃2h后,鸡胚胎素组、模型对照组腹腔注射环磷酰胺60mg/(kg·d),连续4d,复制免疫抑制动物模型。末次给予环磷酰胺2h后颈椎脱位法处死小鼠,计算胸腺、脾脏质量指数。结果:50只小鼠均进入结果分析。①失血前及失血后24h鸡胚胎素组与模型对照组的红细胞数值、血红蛋白含量基本相似(P>0.05)。末次给鸡胚胎素后2h与模型对照组比较,鸡胚胎素组红细胞数值、血红蛋白含量均明显升高(t=3.39,P<0.01;t=2.52,P<0.05)。②末次给环磷酰胺2h后与模型对照组比较,鸡胚胎素组、正常对照组的胸腺质量指数和脾脏质量指数均明显升高(t=6.62,P<0.01;t=2.47,P<0.05)。结论:鸡胚胎素灌胃对血虚小鼠具有较好的促红细胞造血功能,同时对环磷酰胺造成的免疫器官质量下降具有明显的增重作用。 相似文献
82.
JW Mosley ; W Huang ; DO Stram ; MJ Nowicki ; FB Hollinger ; RD Aach ; CE Stevens ; LH Barbosa ; GJ Nemo 《Transfusion》1996,36(9):776-781
BACKGROUND: Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non-B, non-C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti- HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients. STUDY DESIGN AND METHODS: Data on blood donors and recipients enrolled in the Transfusion- Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti-HBc testing of donors and anti-HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients. RESULTS: For HCV cases, donor ALT alone (at > or = 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti-HBc alone (at > or = 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected]. CONCLUSION: The indirect tests proved to be equal in sensitivity to the first-generation anti-HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti-HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepatitis contributed little. 相似文献
83.
The present criteria for confirmation of human T-lymphotrophic virus types I and II (HTLV-I/II) infection in blood donors are based on seroreactivity to p24 (gag) and gp46 and/or gp61 (env) on Western blot (WB) and radioimmunoprecipitation assays (WB/RIPA). Any single band and other combinations are classified as indeterminate. This case report documents infection in a donor with a repeatedly indeterminate pattern. The blood donor was anti-HTLV-I/II positive on enzyme-linked immunoassay, and two sera taken 5 years apart were WB/RIPA-indeterminate (p19 and gp68 only). His donations in the interval were associated with transmission of HTLV-I to four of the six recipients available for study. Other recipients of blood from donors whose WB/RIPA results were indeterminate by present criteria should be examined to determine if additional patterns are at least occasionally associated with transmission. The likelihood that such donors are infected is important to those who are counseling them and making decisions concerning recipients of their bloody. 相似文献
84.
Teasell RW Foley NC Salter KL Jutai JW 《Archives of physical medicine and rehabilitation》2008,89(3):575-578
Teasell RW, Foley NC, Salter KL, Jutai JW. A blueprint for transforming stroke rehabilitation care in Canada: the case for change.Stroke is a major source of disability in Canada and other developed countries, which carries with it a high toll in terms of personal suffering for the stroke survivor and their family in addition to the associated economic costs. Despite the impressive body of evidence describing effective and feasible stroke rehabilitation practices, stroke survivors, their families, and health professionals currently do not benefit from a rehabilitation system that is well organized and evidence based. Using the principles of best evidence, we make the case for needed changes to the current system based on 5 processes of care known to be important in the pursuit of optimal outcomes: (1) admission to specialized stroke rehabilitation units, (2) early admission to stroke rehabilitation units, (3) intensive stroke rehabilitation therapies, (4) task-specific rehabilitation therapies, and (5) well-resourced outpatient programs. Implementation of these strategies will be expected to result in improved functional gain, fewer complications, decreased mortality, and reduced need for institutionalization. In addition to providing improved care for both the stroke survivor and their family, evidence-based stroke rehabilitation care is more efficient and may reduce costs. Our experience in Canada suggests that instituting these 5 measures alone will result in significant improvements to the health care system. 相似文献
85.
RJ Livingston JW Butterworth P Belt 《Annals of the Royal College of Surgeons of England》2013,95(1):e20-e21
Chloramphenicol is a topical treatment that is used widely, especially in wounds around the eyes. In our practice there have been a number of cases of delayed hypersensitivity to chloramphenicol that has been mismanaged initially as an infective cellulitis. We hope to share some of our experience of this uncommon reaction to highlight the delayed reaction that can occur with topical application of this drug. 相似文献
86.
There is a growing body of evidence that sensory neuropathy in diabetes is associated with abnormal calcium signaling in dorsal root ganglion (DRG) neurons. Enhanced influx of calcium via multiple high‐threshold calcium currents is present in sensory neurons of several models of diabetes mellitus, including the spontaneously diabetic BioBred/Worchester (BB/W) rat and the chemical streptozotocin (STZ)‐induced rat. We believe that abnormal calcium signaling in diabetes has pathologic significance as elevation of calcium influx and cytosolic calcium release has been implicated in other neurodegenerative conditions characterized by neuronal dysfunction and death. Using electrophysiologic and pharmacologic techniques, the present study provides evidence that significant impairment of G‐protein‐coupled modulation of calcium channel function may underlie the enhanced calcium entry in diabetes. N‐ and P‐type voltage‐activated, high‐threshold calcium channels in DRGs are coupled to mu opiate receptors via inhibitory G(o)‐type G proteins. The responsiveness of this receptor coupled model was tested in dorsal root ganglion (DRG) neurons from spontaneously‐diabetic BB/W rats, and streptozotocin‐induced (STZ) diabetic rats. Intracellular dialysis with GTPgammaS decreased calcium current amplitude in diabetic BB/W DRG neurons compared with those of age‐matched, nondiabetic controls, suggesting that inhibitory G‐protein activity was diminished in diabetes, resulting in larger calcium currents. Facilitation of calcium current density (I(DCa)) by large‐amplitude depolarizing prepulses (proposed to transiently inactivate G proteins), was significantly less effective in neurons from BB/W and STZ‐induced diabetic DRGs. Facilitation was enhanced by intracellular dialysis with GTPgammaS, decreased by pertussis toxin, and abolished by GDPbetaS within 5 min. Direct measurement of GTPase activity using opiate‐mediated GTPgamma[(35)S] binding, confirmed that G‐protein activity was significantly diminished in STZ‐induced diabetic neurons compared with age‐matched nondiabetic controls. Diabetes did not alter the level of expression of mu opiate receptors and G‐protein alpha subunits. These studies indicate that impaired regulation of calcium channels by G proteins is an important mechanism contributing to enhanced calcium influx in diabetes. 相似文献
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90.
AET White FRCS KG Davies FRCS S Anwar MB JW Neal MRCPath JA Vafidis FRCS 《International journal of clinical practice》1994,48(4):222-223
SUMMARY Intracranial tuberculoma has become a rarity. It remains a curable lesion that responds well to medical therapy. Although diagnosis in developed countries is often made only postoperatively, early and effective treatment can be instituted if a high index of suspicion is maintained and diagnostic criteria are looked for. A case is presented which illustrates the difficulties in reaching a diagnosis, and a review of the literature is given. 相似文献