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991.
应用放射配基结合法测定了人参皂甙Rb_1和Rg_1对α_1,α_2,β肾上腺素能受体、M胆碱能受体、5-羟色胺、多巴胺及GABA等七种受体的作用。结果均不能证明它们对这七种受体有亲和力。但给动物ip药物连续5天,Rb_1和Rg_1均能使中枢M胆碱受体密度显著增高。Rb_1及Rg_1还能显著增加脑内蛋白质的含量。上述实验结果对解释人参的中枢作用提供了重要证据。  相似文献   
992.
楤木根皮中皂甙化学成分的研究   总被引:1,自引:0,他引:1  
楤木根皮中的主要成分是皂甙。将总皂甙以柱层析分离,得到三个化合物(Ⅰ~Ⅲ),经光谱分析和化学方法证明,Ⅰ为楤木皂甙A(araloside A);Ⅱ为银莲花甙(narcissiflorine);Ⅲ是3-O-[β-D-吡喃葡萄糖-(1→2)-β-D-吡喃木糖-(1→)2)-α-L-阿拉伯糖]-齐墩果酸。Ⅲ为一新皂甙,命名为楤木皂甙D(araloside D)。  相似文献   
993.
994.
Occupationally related dysfunction of the peripheral nervous system is a common problem. The signs and symptoms of neurologic problems of the upper extremity and neck that can alter hand function and sensation are described in detail.  相似文献   
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996.
BACKGROUND: Bed sharing with parents has been described as both beneficial to infant well-being and as a potentially lethal situation. OBJECTIVE: To examine trends in bed sharing between infants and caregivers, and the factors that influence this behavior. DESIGN: Annual nationally representative telephone surveys conducted between 1993 and 2000. SETTING: The 48 contiguous United States. PARTICIPANTS: Nighttime caregivers of infants born within 7 months prior to interview between 1993 and 2000. Approximately 1000 interviews were conducted each year for a total sample of 8453 nighttime caregivers. MAIN OUTCOME MEASURES: Where and with whom the infant usually slept at night in the preceding 2 weeks. RESULTS: Forty-five percent of infants spent at least some time at night on an adult bed in the last 2 weeks. Between 1993 and 2000, the proportion of infants usually sharing an adult bed at night increased from 5.5% to 12.8%. More than 90% of infants who "usually" slept on an adult bed shared it with their parents. In a multivariate analysis, factors associated with increased probability of routine bed sharing included: maternal age less than 18 years (odds ratio [OR] = 2.26; 95% confidence interval [CI], 1.22-4.21), maternal race or ethnicity reported as black (OR = 4.04; 95% CI, 3.04-5.36) or as Asian or "other" (OR = 2.72; 95% CI, 1.74-4.22), household income less than $20,000 (OR = 1.49; 95% CI, 1.15 = 1.92), living in the Southern states compared with living in the Midwest (OR, 1.59; 95% CI = 1.23, 2.06), and infant age less than 8 weeks (OR = 1.60; 95% CI, 1.10-2.33). Living in the Mid-Atlantic compared with the Midwest (OR = 0.63; 95% CI, 0.44-0.90), and being born with low birthweight and preterm (OR = 0.32; 95% CI, 0.14-0.74) were associated with decreased probability of routine bed sharing. CONCLUSIONS: Bed sharing as a routine practice is growing in the United States. Given that this practice seems to be widespread and strongly influenced by cultural factors, more studies of the consequences of bed sharing are needed to inform health care providers and parents on the risks and benefits.  相似文献   
997.
METHODS: Two hundred twenty-three recipients of first cadaveric kidney allografts were randomized to receive tacrolimus (TAC) + mycophenolate mofetil (MMF), TAC + azathioprine (AZA), or cyclosporine (Neoral; CsA) + MMF. All regimens contained corticosteroids, and antibody induction was used only in patients who experienced delayed graft function (DGF). Patients were followed-up for 3 years. RESULTS: The results at 3 years corroborate and extend the findings of the 2-year results. Patients with DGF treated with TAC+MMF experienced an increase in 3-year allograft survival compared with patients receiving CsA+MMF (84.1% vs. 49.9%, P=0.02). Patients randomized to either treatment arm containing TAC exhibited numerically superior kidney function when compared with CsA. During the 3 years, new-onset insulin dependence occurred in 6, 3, and 11 patients in the TAC+MMF, CsA+MMF, and TAC+AZA treatment arms, respectively. Furthermore, patients randomized to TAC+MMF received significantly lower doses of MMF as compared with those who received CsA+MMF. CONCLUSION: All three immunosuppressive regimens provided excellent safety and efficacy. However, the best results overall were achieved with TAC+MMF. The combination may provide particular benefit to kidney allograft recipients with DGF. In patients who experienced DGF, graft survival was better at 3 years in those patients receiving TAC in combination with either MMF or AZA as compared with the patients receiving CsA with MMF.  相似文献   
998.
999.
BACKGROUND: Anemia is a common occurrence in the intensive care unit (ICU). Although resuscitation, including the use of blood, is a mainstay of early treatment of trauma victims, the safety and efficacy of red blood cell (RBC) transfusion has come under scrutiny recently. The issue of blood use in critically injured patients requires evaluation. METHODS: This was a post hoc analysis of a subset of trauma patients (> or =18 years in age) from a prospective, multicenter, observational, cohort study in the United States. Patients were enrolled within 48 hours after ICU admission and followed for up to 30 days, or until hospital discharge or death. RESULTS: Five hundred seventy-six patients from 111 ICUs in 100 hospitals were enrolled between August 2000 and April 2001. At baseline, mean age was 44.1 +/- 20.2 years, 73.6% were men, and mean APACHE II score was 16.9 +/- 8.2. Mean baseline hemoglobin was 11.1 +/- 2.4 g/dL and patients remained anemic throughout the study either with or without transfusion; 55.4% of patients were transfused (mean, 5.8 +/- 5.5 units) during the ICU stay and 43.8% of patients had an ICU length of stay > or = 7 days. Mean pretransfusion hemoglobin was 8.9 +/- 1.8 g/dL. Mean age of RBCs transfused was 20.1 +/- 11.4 days. As compared with the full study population, patients in the trauma subset were more likely to be transfused and received an average of 1 additional unit of blood. CONCLUSION: Anemia is common in critically injured trauma patients and persists throughout the duration of critical illness. These patients receive a large number of RBC transfusions during their ICU course with aged blood.  相似文献   
1000.
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