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101.
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
102.
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
103.
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
104.
Objective
To investigate the association between serum levels of 25-hydroxyvitamin D and the occurrence of simultaneous fractures of the upper limb in older women who sustain a fall-related fracture of the hip.Study design
Cross-sectional study.Main outcome measures
We investigated 472 of 480 white women consecutively admitted to a rehabilitation hospital because of a fall-related hip fracture. Twenty-seven (5.7%) of the 472 women sustained a concomitant upper-limb fracture of either distal radius (20 women) or proximal humerus (seven women). We assessed serum levels of 25-hydroxyvitamin D 14.2 ± 4.1 (mean ± SD) days after surgical repair of the hip fracture in the 472 women by an immunoenzymatic assay.Results
Twenty-five-hydroxyvitamin D levels were significantly lower in the 27 women with concomitant fractures of both hip and upper limb than in the remaining 445 hip-fracture women: mean ± SD values were 6.5 ± 5.0 ng/ml and 11.7 ± 10.4 ng/ml respectively in the two groups (mean difference between groups 5.2 ng/ml: 95% CI 1.2–9.2; p = 0.011). Low levels of 25-hydroxyvitaimn D were significantly associated with concomitant fractures of the upper limb (p = 0.017), after adjustment for eight potential confounders including age, height, weight, hip-fracture type, cognitive impairment, neurologic impairment, previous hip fracture, and previous upper-limb fracture.Conclusions
Low levels of 25-hydroxyvitamin D were significantly associated with concomitant upper-limb fractures in our sample of older women with a fall-related fracture of the hip. Preventing vitamin D deficiency may lower the incidence of simultaneous fractures due to a singe fall in elderly women. 相似文献105.
Leelawiwat W Young NL Chaowanachan T Ou CY Culnane M Vanprapa N Waranawat N Wasinrapee P Mock PA Tappero J McNicholl JM 《Journal of virological methods》2009,155(2):109-117
Molecular methods for HIV-1 infection using dried blood-spot (DBS) for HIV-1 CRF01_AE subtypes have not been fully optimized. In this study assays for HIV-1 diagnosis or quantitation were evaluated using infant DBS from Thailand. Paired DBS and whole blood samples from 56 HIV-1 CRF01_AE or B'-infected infants were tested for infant diagnosis using modified Amplicor DNA PCR and NucliSens RNA NASBA and an in-house real-time PCR assay. The Amplicor Monitor viral load (VL) assay, with modifications for DBS, was also evaluated. DBS VL were hematocrit corrected. Stability studies were done on DBS stored at -70 degrees C to 37 degrees C for up to 1 year. The DBS diagnostic assays were 96-100% sensitive and 100% specific for HIV-1 diagnosis. DBS HIV-1 VL were highly correlated with plasma VL when corrected using the actual or an assumed hematocrit factor (r(c)=0.88 or 0.93, respectively). HIV-1 DNA in DBS appeared to be more stable than RNA and could be detected after up to 9 months at most temperatures. DBS VL could be consistently determined when stored frozen. These results show that DBS can be used accurately instead of whole blood for the diagnosis of HIV-1 infection and VL quantitation, particularly if samples are appropriately stored. 相似文献
106.
Creek D Bigira V Arinaitwe E Wanzira H Kakuru A Tappero J Kamya MR Dorsey G Sandison TG 《The American journal of tropical medicine and hygiene》2010,83(4):873-875
Artemether-lumefantrine (AL) and dihydroartemisinin-piperaquine (DP) are highly efficacious antimalarial therapies in Africa. However, there are limited data regarding the tolerability of these drugs in young children. We used data from a randomized control trial in rural Uganda to compare the risk of early vomiting (within one hour of dosing) for children 6-24 months of age randomized to receive DP (n = 240) or AL (n = 228) for treatment of uncomplicated malaria. Overall, DP was associated with a higher risk of early vomiting than AL (15.1% versus 7.1%; P = 0.007). The increased risk of early vomiting with DP was only present among breastfeeding children (relative risk [RR] = 3.35, P = 0.001) compared with children who were not breastfeeding (RR = 1.03, P = 0.94). Age less than 18 months was a risk factor for early vomiting independent of treatment (RR = 3.27, P = 0.02). Our findings indicate that AL may be better tolerated than DP among young breastfeeding children treated for uncomplicated malaria. 相似文献
107.
Marco Di Monaco MD Fulvia Vallero MD Roberto Di Monaco DPS Rosa Tappero MD Alberto Cavanna MD 《Archives of physical medicine and rehabilitation》2008,89(12):2297-2301
Di Monaco M, Vallero F, Di Monaco R, Tappero R, Cavanna A. Type of hip fracture in patients with Parkinson disease is associated with femoral bone mineral density.
Objective
To investigate the association between bone mineral density (BMD) and hip fracture type (cervical or trochanteric) in a sample of fallers with Parkinson disease (PD).Design
Observational study.Setting
Rehabilitation hospital in Italy.Patients
We investigated 1040 of 1120 white fallers consecutively admitted to a rehabilitation hospital for hip fracture. Thirty-eight (3.65%) of the 1040 patients suffered from PD secondarily. Thirty-eight controls matched for sex, age, and hip fracture type were found among the 1002 non-PD fallers.Interventions
Not applicable.Main Outcome Measures
BMD was assessed by dual-energy x-ray absorptiometry at a mean ± SD of 21.9±7.5 days after fracture occurrence in the 38 PD patients and 21.6±5.9 days after fracture occurrence in the 38 controls.Results
BMD assessed at total femur, trochanter, and intertrochanteric region was significantly lower in the 15 PD patients with trochanteric fractures than in the 23 with cervical fractures; the mean T score differences were 0.57 (95% confidence interval [CI], 0.07–1.08; P=.028), 0.66 (95% CI, 0.04–1.28; P=.037), and 0.63 (95% CI, 0.11–1.15; P=.019), respectively. A significant association between femoral BMD and hip fracture type was found at logistic regression after adjustment for several confounders. Results in the 38 controls were similar to those obtained in the 38 PD fallers.Conclusions
In a sample of PD fallers as in a control group of non-PD fallers, BMD levels assessed at 3 femoral sites were significantly lower in the patients who sustained trochanteric fractures than in those with cervical fractures of the hip. 相似文献108.
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
109.
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
110.