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目的建立人血浆中醋酸环丙孕酮的HPLC—ESI—MS测定方法和丹酰氯衍生化血浆中炔雌醇的HPLC—APCI—MS测定方法,测定女性志愿者口服复方醋酸环丙孕酮片1片后的药代动力学参数,并对受试制剂和参比制剂的生物等效性进行评价。方法血浆样品中的炔雌醇以乙酸乙酯提取后,与丹酰氯发生衍生化反应,进行HPLC—APCI—MS分析,流动相为10mmol·L-1乙酸铵缓冲液(1%甲酸)-甲醇(3:97)。检测离子分别为m/z530.3(炔雌醇的丹酰氯衍生物)、m/z404.3(内标,对羟基联苯的丹酰氯衍生物1。结果在10.43~625.8Pg·ml-1范同内炔雌醇的丹酰氯衍生物与内标的丹酰氯衍生物峰面积比值与浓度呈良好的线性关系,最低定量限为10.43pg·ml-1结论本实验建立的分析方法灵敏、准确、简便,且统计学结果表明两种制剂生物等效。 相似文献
54.
Anna E. Kornadt Isabelle Albert Martine Hoffmann Elke Murdock Josepha Nell 《European journal of ageing》2021,18(2):173
In the Covid-19 pandemic, being older means being in a special focus: Probabilities for severe infections and mortality rise with increasing age and protective measures for this population group have been increased. This was accompanied by public discourse that portrayed older adults stereotypically as vulnerable and frail but also highlighted the hardships younger people have to endure to protect them. Given the possibly detrimental effects of ageism on individuals and societies, we were interested in older adults’ perception of ageism in the Corona-crisis and its relation to their health and well-being. Furthermore, we were interested in subjective aging variables as moderators in the ageism–health relationship. In June 2020, N = 611 independently living people aged 60 + from the Grand Duchy of Luxembourg were recruited via a survey research institute and interviewed online or by phone. They reported on perceived ageism in different contexts, their life satisfaction, subjective health, subjective age and self-perceptions of aging. Depending on context, ageism was perceived by around 20% of participants, and overall negatively related to subjective health and life satisfaction after the onset of the pandemic. Moderated hierarchical regressions showed that a younger subjective age buffered the negative effect of ageism on subjective health, while perceiving aging as social loss increased its effect on life satisfaction. We discuss the importance of addressing and reducing ageism (not only) in times of crisis and the consequences for individuals and societies. 相似文献
55.
Platelet-melanoma cell interaction is mediated by the glycoprotein IIb- IIIa complex 总被引:3,自引:0,他引:3
A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions. 相似文献
56.
Z E Piao D K Murdock M H Hwang R M Raymond P J Scanlon 《Catheterization and cardiovascular diagnosis》1988,14(1):53-58
Coronary angiography with standard ionic contrast media is associated with marked alterations in cardiac hemodynamics because of the depressant effects of the contrast media on cardiac contractility. Nonionic contrast media have been reported to produce less hemodynamic alteration than standard ionic contrast media. However, there is no information on how one nonionic media compares to another. Thus we compared the hemodynamic effects of three nonionic contrast media, Iopamidol (IOP), Iohexol (IOH), and Ioversol (IOV) to each other as well as to the standard ionic contrast media Hypaque-76 (H76). In 20 closed-chest anesthetized dogs, we recorded the maximal change in left ventricular systolic pressure (LVSP), mean aortic pressure, left ventricular diastolic pressure (LVDP), and left ventricular dp/dt during 10-cc left main coronary artery injections of H76, IOP, IOH, and IOV. The mean aortic pressure and LVSP decreased 36 +/- 17 mm Hg and 46 +/- 21 mm Hg with H76 but only 5 +/- 5 mm Hg and 6 +/- 5 mm Hg with IOP, 5 +/- 4 mm Hg and 6 +/- 6 mm Hg with IOH, and 5 +/- 4 mm Hg and 7 +/- 6 mm Hg with IOV (P less than 0.001). The LVDP increased 6 +/- 5.0 mm Hg with H76 but only 0.2 +/- 0.5 mm Hg with IOP, 0.2 +/- 0.3 mm Hg with IOH, and 0.5 +/- 1.0 mm Hg with IOV (P less than 0.001). The LV dp/dt decreased 545 +/- 261 mm Hg/sec with H76 but increased 886 +/- 477 mm Hg/sec with IOP, 910 +/- 96 mm Hg/sec with IOH, and 473 +/- 335 mm Hg/sec with IOV (P less than 0.001). Whereas each nonionic agent produced significantly less hemodynamic abnormalities than H76, there was no significant difference between any of the nonionic agents on any hemodynamic parameter. Thus, as compared to H76, these nonionic contrast media produced only trivial alterations in hemodynamics and LV dp/dt. These agents may be preferable in patients with LV dysfunction. 相似文献
57.
A. C. Harbin G. Bandi A. A. Vora X. Cheng V. Stanford K. McGeagh J. Murdock R. Ghasemian J. Lynch F. Bedell M. Verghese J. J. Hwang 《Journal of robotic surgery》2014,8(1):23-27
Laparoscopic and robotic partial nephrectomy have become the preferred option for surgical management of incidentally discovered small renal tumors. Currently there is no consensus on which aspects of the procedure should be performed laparoscopically versus robotically. We believe that combining a laparoscopic exposure and hilar dissection followed by tumor extirpation and renorrhaphy with robotic assistance provides improved perioperative outcomes compared to a pure robotic approach alone. We performed a comparison of perioperative outcomes between combined laparoscopic–robotic partial nephrectomy—or hybrid procedure—and pure robotic partial nephrectomy (RPN). A multi-center retrospective analysis of patients undergoing RPN and hybrid PN using the da Vinci S system® was performed. Patient data were reviewed for demographic and perioperative variables. Statistical analysis was performed using the Welch t test and linear regression, and nonparametric tests with similar significance results. Thirty-one patients underwent RPN while 77 patients underwent hybrid PN between 2007 and 2011. Preoperative variables were comparable in both groups with the exception of lesion size and nephrometry score which were significantly higher in patients undergoing hybrid PN. Length of surgery, estimated blood loss and morphine used were significantly less in the hybrid group, while warm ischemia time was significantly longer. The difference in WIT was accounted for in this data by adjusting for nephrometry score. In our multi-center series, the hybrid approach was associated with a shorter operative time, reduced blood loss and lower narcotic usage. We believe this approach is a valid alternative to RPN. 相似文献
58.
LL Patton 《Oral diseases》2014,20(3):223-225
Over the last 30 years, there have been significant advances in our scientific knowledge of HIV disease, including prevention, detection, medical management, and attempts at cure. Investigations and observations of the oral cavity in individuals with HIV disease have contributed substantially to scientific discovery and innovation. Challenges remain for managing existing and emerging oral diseases associated with HIV and understanding the contribution of latent oral mucosal reservoirs to HIV eradication. 相似文献
59.
Effect of transforming growth factor-beta 1 on proliferation and induction of hemoglobin accumulation in K-562 cells 总被引:1,自引:1,他引:1
The effects of transforming growth factor-beta 1 (TGF-beta 1) on proliferation and hemoglobinization in K-562 cells, a human multipotential hematopoietic cell line, were studied. We found that TGF- beta 1 could induce hemoglobin accumulation in K-562 cells. Various clones were selected on the basis of the inducibility of hemoglobinization by TGF-beta 1. One high response clone (no. 1) and one low response clone (no. 8) were studied in detail. Hemoglobin accumulation peaked on day 5 of culture in the presence of TGF-beta 1 (0.5 ng/mL, 20 pmol/L), when 90% of clone 1 cells, 55% of parent line cells, and less than 10% of clone 8 cells contained hemoglobin. There was a concomitant reduction in proliferation of 60% for clone 1, 40% for the parent line, and 30% for the clone 8 on day 5 of culture. Quantitative analysis showed that the hemoglobin contents in clone 1 after 5-day induction by TGF-beta 1 and hemin were 1.0 pg/cell and 2.9 pg/cell, respectively. The hemoglobin induced by TGF-beta 1 showed the same electrophoretic characteristics as the hemoglobin induced by hemin. The expression of epsilon-globin mRNA was minimally detectable in control cells and was induced in both TGF-beta 1 and hemin treated cells. Other cytokines with potential effects on K-562 cell proliferation and differentiation were also studied. Interleukin-1, interleukin-3, interferon alpha, interferon gamma, and inhibin, tested as single agents, showed minimal effects on proliferation. None of these agents could induce hemoglobinization or inhibit the hemoglobinization induced by TGF-beta 1. 相似文献
60.