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排序方式: 共有309条查询结果,搜索用时 140 毫秒
1.
A total of 158 males with coronary risk factors and excessive (4 to 55% above normal) body weight were treated by diet and exercise for hyperlipoproteinemia in an out-patient clinic for 18 months. Blood cholesterol decreased significantly, by 14.4% (p less than 0.001), in 10% of the males who had lost at least 10% of excessive weight. Blood triglycerides decreased by 23% in 22% of the patients, who had lost 5.5% and more of excessive body weight (p less than 0.01). A two-month course of treatment with essential forte in combination with diet and regular exercise reduced blood cholesterol by 15.1% in 62%, and blood triglycerides, by 44.5% in 61.9% (p less than 0.001).  相似文献   
2.
Using the method of ATP luminometry it is shown that crude membrane preparations from human and rat hepatocytes accumulate ATP 20–100 nmol/mg protein during a 1-min incubation under conditions of oxidative phosphorylation. Application of appropriate inhibitors shows that a possible contamination of the membrane preparations with mitochondria does not contribute to this ATP accumulation. Phosphatidylcholine, tumor necrosis factor, and cell proliferation factor markedly stimulate the accumulation of ATP by plasma membraneenriched particles isolated from rat and human liver. The hepatocyte plasma membrane is shown to be able to synthesize ATP from inorganic phosphate and ADP using the aerobic mechanism. ATP in the plasma membrane is assumed to participate in the transmembrane signal transduction from growth factors to the cell effector systems. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N o 3, pp. 271–274, March, 1996 Presented by V. D. Fedorov, Member of the Russian Academy of Medical Sciences  相似文献   
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目的 建立一种快速、灵敏的高效液相色谱-串联质谱(HPLC-MS/MS)方法以测定人血浆中对乙酰氨基酚浓度,并应用于两种对乙酰氨基酚制剂的人体药代动力学和生物等效性研究。方法 以替硝唑为内标,200μL血浆样品经5倍于其体积的乙酸乙酯液液萃取,再经Waters XBridge? C18柱等度洗脱分离后导入串联质谱,以正离子多反应监测模式进行定量分析,对乙酰氨基酚和内标的选择性反应离子对分别是m/z 152→110和248→121。方法经验证后应用于19名健康受试者单剂量空腹口服两种对乙酰氨基酚制剂500mg后药代动力学和生物等效性的研究。结果 血浆中对乙酰氨基酚在0.1~8.0 μg·mL-1范围内线性良好(r2 > 0.99),最低检测限为 0.1 μg·mL-1,提取回收率为91.0%~98.7%,日内和日间准确度分别为98.8%~111.3% (精密度:CV ? 9.03%)和94.9%~102.6% (精密度:CV ? 10.68%)。生物等效性试验中,受试制剂与参比制剂的主要药代动力学参数Cmax、AUC0-t和AUC0-∞ 几何均值比的90%置信区间分别为83.50%~105.79%,94.25%~101.54%和93.24%~101.02%,均落在生物等效可接受标准80.00%~125.00%范围内。结论 所建立测定人血浆中对乙酰氨基酚浓度的HPLC-MS/MS法具有快速灵敏、回收率高、选择性好的特点,适用于对乙酰氨基酚片人体药代动力学和生物等效性研究。受试制剂与参比制剂在人体内吸收速度和程度相似,两种制剂生物等效。  相似文献   
5.
Addition of capping agents like surfactants and polymers during the synthesis of nanoparticles may affect the stability and toxicity of dispersions of nanoparticles. This study revealed the impact of anionic, cationic, and amphoteric surfactants and a cationic polymer on the physical and chemical properties, stability and behavior of silver nanomaterials, as well as on the toxicity of nanosized silver particles with respect to zebrafish embryos. Some of the stabilizers applied were shown to significantly affect embryos of Danio rerio. Colloidal dispersions of stabilized silver nanoparticles were demonstrated to induce a complex mechanism of toxicity with respect to embryos of D. rerio, which is mainly explained by the toxicity of the organic ligand, while other parameters are somewhat inferior. The newly generated data on the toxicity of nanoparticles and their stabilizers with respect to D. rerio embryos reveal the complexity of the toxicity mechanism of nanoparticles impacting living systems.  相似文献   
6.
We present the results of treatment of chronic ischemia of the lower extremities (distal form) with angiogenesis stimulators, autologous endothelioblast precursors (CD133+) and gene preparation of vascular endothelial growth factor VEGF165 (angiostimulin). Good clinical effect was attained in all patients, which was confirmed instrumentally 1, 3, and 6 months after administration of the stimulant: transcutaneous oxygen tension on the foot, index of malleolar pressure, and walking duration increased, parameters of microcirculation improved, the number of newly formed collateral arteries increased (angiography findings), quality of life improved (SF 36 questionnaire), and parameters of coagulogram also improved. The maximum positive dynamics was observed by month 3 of the study. __________ Translated from Kletochnye Tehnologii v Biologii i Medicine, No. 3, pp. 159–164, July, 2007  相似文献   
7.
AIM: To test feasibility of transplantation of hemopoietic stem cells (THSC) with conditioning in low-intensity regimen associated with minimal toxic complications and engraftment in patients with hematological malignancy (HM) from a high risk group. MATERIAL AND METHODS: THSC was performed in 33 patients aged 18 to 65 years. Most of the patients suffered from acute leukemia and advanced forms of myelodysplastic syndrome. All the patients had severe complications excluding standard transplantation. Pretransplantation preparation was based on fludarabine and moderate doses of busulfane. Engraftment was achieved in 94% patients. Of complications, there were primarily infections, relapses, graft versus host reactions (45, 24, 57.5%, respectively). Overall survival was 53%, relapse-free--67%, follow-up median 23.6 months. CONCLUSION: THSC after conditioning in the regime of low intensity is an effective method of HM treatment in patients with contraindications to standard transplantation. The main problem is a high risk to develop graft versus host reaction, especially a chronic form.  相似文献   
8.
AIM: To analyse results of transplantation of allogenic and autologous hemopoietic stem cells (allo-THSC and auto-THSC) with myeloablation preconditioning in patients with acute leukemia (AL) performed in 1987-2006. MATERIAL AND METHODS: A total of 71 allogenic and 45 autologous THSC were performed in 116 patients with different AL variants. Conditioning in all allo-THSC included busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg). This regimen was used in 29 recipients of auto-HSC. Cyclophosphamide in a dose 120 mg/kg and total radiation of the body in a dose 12 Gy were given to 16 recipients. Overall, relapse-free and event-free survival of patients after THSC were analysed as well as early (first 100 days) and overall lethality. Auto-THSC in 15 patients was for the first time followed by immunomodulating therapy aimed at prevention of AL relapses: in acute myeloid leukemia ATRA in combination with alpha-interferon, in acute lymphoblastic leukemia (ALL)--ronkoleukin, interleukin-2 preparation. RESULTS: Overall survival of AL patients after allo-THSC for the observation period increased from 31 to 58%, early lethality fell from 44 to 4%. Results of allo-THSC conducted in the first complete remission were much better than in patients with other AL stages at the time of THSC. After auto-THSC 5-year survival rose from 22 to 60% while early lethality reduced from 33 to 4%. Administration of immunomodulating therapy after auto-THSC increases 5-year survival from 35 to 80%. CONCLUSION: Outcomes of THSC in AL has improved for the last 20 years. Outcomes of allo-THSC performed in the first complete remission are much higher. Immunomodulating therapy after auto-THSC promoted better results.  相似文献   
9.
Adhesion of platelets to surface-bound fibrinogen under flow   总被引:2,自引:2,他引:2  
Zaidi  TN; McIntire  LV; Farrell  DH; Thiagarajan  P 《Blood》1996,88(8):2967-2972
After platelet activation, fibrinogen mediates platelet-platelet interactions leading to platelet aggregation. In addition, fibrinogen can also function as a cell adhesion molecule, providing a substratum for adhesion of platelets and endothelial cells. In this report, we studied the adhesion of platelets to surface-immobilized fibrinogen under flow in different shear rates. Heparinized whole blood containing mepacrine-labeled platelets was perfused for two minutes at various wall shear rates from 250 to 2,000 s-1 in a parallel plate flow chamber. The number of adherent fluorescent platelets was quantitated every 15 seconds with an epifluorescent videomicroscope and digital image processing system. When compared with platelet adhesion and aggregation seen on glass surfaces coated with type I bovine collagen, a significant increase in platelet adhesion was observed on immobilized fibrinogen up to wall shear rates of 800 s-1. The adherent platelets formed a single layer on fibrinogen-coated surfaces. Under identical conditions, no significant adhesion was observed on fibronectin- or vitronectin-coated surfaces. Although platelet adhesion to collagen was substantially inhibited by the platelet inhibitors prostaglandin E1 and theophylline, these inhibitors had no effect on platelet adhesion to fibrinogen. Platelets adhered to recombinant homodimeric wild-type (gamma 400-411) fibrinogen, but not to the recombinant homodimeric gamma' variant of fibrinogen. Platelet adhesion to recombinant fibrinogen with RGD to RGE mutations at positions alpha 95-97 and alpha 572-574 was similar to that with plasma-derived fibrinogen. These results show that platelets adhere to fibrinogen-coated surfaces under moderate wall shear rates, that the interaction is mediated by the fibrinogen 400-411 sequence at the carboxy-terminus of the gamma chain, and that the interaction is independent of platelet activation and the RGD sequences in the alpha chain.  相似文献   
10.
Lucas  KG; Small  TN; Heller  G; Dupont  B; O'Reilly  RJ 《Blood》1996,87(6):2594-2603
Epstein-Barr virus-induced lymphoproliferative disease (EBV-LPD) is a potentially lethal complication during the first 6 months after allogeneic bone marrow transplantation (BMT). To determine whether deficiencies of EBV-specific cellular immunity contribute to EBV-LPD susceptibility and distinguish patients at risk, we performed limiting dilution analysis to quantify anti-EBV cytotoxic T-lymphocyte precursor (CTLp) frequencies in 26 recipients of unmodified or T-cell-depleted (TCD) grafts from EBV-seropositive donors. At 3 months post-BMT (n = 26), only five patients had EBV CTLp frequencies in the range of seropositive normal controls, irrespective of the type of transplant administered. By 6 months post-BMT, 9 of 13 patients tested had EBV CTLp frequencies within the normal range. The time period in which these patients had deficient cellular immunity to EBV corresponds to the period in which we have observed EBV-LPD in most prior patients. One patient with a low EBV CTLp frequency at 4 months post-BMT developed an EBV-LPD. Within 2 weeks of receiving an infusion of donor peripheral blood mononuclear cells (PBMC) providing less than 1,200 EBV- specific cytotoxic T-cell precursors, populations of EBV-specific CTL in the circulation were restored to levels detected in normal seropositive adults. Concurrently, the patient achieved a regression of the EBV-LPD, which has been sustained without further therapy. These studies indicate that recipients of both unmodified and TCD marrow grafts have profound deficiencies of EBV-specific T cell-mediated immunity early posttransplant, and that the period of risk for EBV-LPD closely corresponds to this interval of severe deficiency. Treatment of one patient with EBV-LPD with marrow donor-derived PBMC induced a rapid expansion of EBV-specific cytotoxic T-cell populations that occurred contemporaneously with the clinical regression of disease.  相似文献   
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