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91.
裂解剂的残余含量是流感病毒裂解疫苗的主要质控指标之一。实验中采用膜超滤法和透析法做了裂解剂去除的比较研究。结果表明,膜超滤法效果优于透析法。其血凝素抗原纯化收率达到90%,裂解剂去除达98%以上;疫苗生产无菌操作和细菌内毒素易于控制,成本低,易于大规模生产。  相似文献   
92.
In vivo microdialysis was used to investigate the regulation of noradrenaline release in rat hippocampus. Idazoxan, an alpha 2-adrenoreceptor antagonist (1-10 mg/kg), increased noradrenaline release in a dose-dependent manner. Inhibition of noradrenaline uptake by desipramine (0.05-20 microM; via the probe) also increased the extracellular content of the transmitter. In the presence of this increased noradrenaline content (desipramine via the probe), the effect of a low dose of idazoxan (1 mg/kg) was potentiated. Local perfusion of idazoxan (1-500 microM) in the hippocampus also increased noradrenaline release but not to the same extent as following systemic administration. In the presence of desipramine, unlike the systemic injection of idazoxan, local perfusion did not potentiate noradrenaline release. The data are consistent with the regulation of extracellular noradrenaline content in the hippocampus by neuronal uptake and to a lesser extent by presynaptic autoreceptors.  相似文献   
93.
Objective:  To define a minimum acceptable total squamous cellularity for (ThinPrep®) liquid-based cervical cytology (LBC) specimens using quality control techniques.
Methods:  Two hundred LBC preparations were made containing varying numbers (<200) of severely dyskaryotic squamous cells and with varying total cellularities.
Results:  Ninety-eight per cent of the LBC preparations that were missed by one or more of three cytoscreeners had fewer than 16 abnormal objects (single dyskaryotic cells or clumps of cells) and 87 dyskaryotic cells. The minimum ratio of dyskaryotic to total squamous cells that, in a preparation of 5000 squamous cells has a probability of at least 0.98 that 87 or more dyskaryotic cells will be present is 1 : 47. Twenty-three preparations diagnosed as abnormal had ratios of dyskaryotic to total squamous cells of between 1 : 2.5 and 1 : 4596. There is thus no feasible minimum acceptable squamous cellularity that will give an acceptable probability of detection of all specimen vials containing abnormal cells in the observed proportions.
Conclusions:  It is suggested that the minimum acceptable cellularity for LBC specimens is set pragmatically by the screening programme to give a feasible percentage of repeat tests.  相似文献   
94.
The BSCC terminology was originally published in 1986 and although highly successful, requires revision. Through a process of professional consensus and literature review this has been undertaken by the BSCC. The revision takes account of recent developments and improvements in understanding of morphology and disease process and is compatible with other terminologies in use elsewhere, whilst still maintaining a focus on practice in the UK cervical screening programmes.  相似文献   
95.
Methanolysis (transesterification with methanol) of sunflower oil by lipase from Candida antarctica (Novozym 435) in a solvent-free system has been studied. Stepwise as well as continuous methanol feeding was applied to avoid strong substrate inhibition. Glycerol was found to cause strong product inhibition on the enzymatic reaction, therefore glycerol removal by dialysis was investigated using a flat sheet membrane module.  相似文献   
96.
BackgroundWarfarin is traditionally the drug of choice for stroke prophylaxis or treatment of venous thromboembolism in patients with end-stage renal disease (ESRD) on hemodialysis as data on apixaban use is scarce. We aimed to assess the safety and efficacy of Apixaban in patients with ESRD on hemodialysis when compared with warfarin.MethodsA comprehensive literature search in PubMed, Google Scholar, and Cochrane databases from inception until Nov 25, 2019, was performed. Studies reporting clinical outcomes comparing Apixaban (2.5 mg BID or 5 mg BID) versus Warfarin in ESRD patients on hemodialysis were included. Mantel-Haenszel risk ratio (RR) random-effects model was used to summarize data.ResultsFour studies (three retrospective and one randomized) with a total of 9862 patients (apixaban = 2,547, warfarin = 7315) met inclusion criteria. The overall mean age was 66.6 ± 3.9 years and mean CHA2DS2-VASc score 4.56 ± 0.58. Apixaban was associated with lower rates of major bleeding (RR 0.53, 95% CI 0.45–0.64, p < 0.0001], gastrointestinal (GI) bleed (RR 0.65, 95% CI 0.55–0.76, p < 0.0001), intracranial bleed (RR 0.56, 95% CI 0.36–0.89, p = 0.01), and stroke/systemic embolism [RR 0.65, 95% CI 0.52–0.83, p = 0.0004] compared with warfarin in patients with ESRD on hemodialysis. There was no significant increased risk of all-cause mortality with the apixaban vs. warfarin (RR 0.90, 95% CI 0.41–1.96, p = 0.78).ConclusionApixaban had an overall favorable risk-benefit profile, with significant reductions in ischemic stroke, major bleeding, and intracranial bleeding compared to Warfarin in ESRD patients on hemodialysis with non-valvular AF and/or venous thromboembolism.  相似文献   
97.
Objective:  The aim of this study was to develop a new reporting format for endometrial cytology that would standardize the diagnostic criteria and the terminology used for reporting.
Methods:  In previous studies, cytoarchitectural criteria were found to be useful for the cytological assessment of endometrial lesions. To apply these criteria, an appropriate cytological specimen is imperative. In this article, the requirements of an adequate endometrial cytological specimen for the new diagnostic criteria are first discussed. Then, the diagnostic criteria, standardized on a combination of conventional and cytoarchitectural criteria, are presented. Third, terminology that could be used, not only for reporting the histopathological diagnosis, but also for providing better guidance for the gynaecologist to determine further clinical action, is introduced. The proposed reporting format was investigated using endometrial cytology of 58 cases that were cytologically underestimated or overestimated compared to the histopathological diagnosis made on the subsequent endometrial biopsy or surgical specimens.
Results:  Of the 58 cases, 12 were reassessed as being unsatisfactory for evaluation. Among the remaining 46 cases, 25 of the 27 cases, which had been underestimated and subsequently diagnosed as having endometrial carcinoma or a precursor stage on histopathological examination,were reassessed as recommended for endometrial biopsy. On the other hand, 19 cases overestimated by cytology were all reassessed as not requiring biopsy.
Conclusions:  The reporting format for endometrial cytology proposed in this article may improve diagnostic accuracy and reduce the number of patients managed inappropriately.  相似文献   
98.
Whole blood and serum samples of Chinese stable chronic renal failure (CRF) patients (n = 81), hemodialysis patients (n = 135), posttransplant patients (n = 60), and subjects with normal renal function (NRF; N = 42) were collected, as well as water and dialysate samples from five dialysis centers. The concentration of selenium (Se), lead (Pb), and cadmium (Cd) was measured by atomic absorption spectrometry. The mean serum Se levels in patients with different degrees of renal failure were significantly lower than those of subjects with NRF (p < 0.01). Pb levels were not increased in renal failure patients, while the Cd levels in patients with various degrees of renal failure were higher than in subjects with NRF (p < 0.05). After correcting the results of Pb and Cd for hematocrit (Hct) however, Pb levels of dialysis patients were also increased. In the dialysis population under study, blood Pb and Cd levels were closely related to the time on dialysis, while contamination of the final dialysate may also contribute to the increased blood Cd and to a less extent Pb levels. Correction for Hct may be recommended to accurately compare blood Pb and Cd levels in dialysis patients and CRF patients with varying degrees of anemia to those of subjects with NRF.  相似文献   
99.
T-cell functions are currently used as biomarkers for the pharmacodynamic monitoring of immunosuppressive drugs or as disease biomarkers of inflammation/sepsis and organ rejection. In order to evaluate co-factors potentially influencing the expression of the immunological biomarkers, we explored T-cell proliferation, T-cell activation (CD25 and CD71 expressions) and intra-lymphocyte cytokine production (interleukin (IL)-2 and tumor necrosis factor (TNF)-α) in healthy volunteers, dialysis patients and stable kidney-transplant patients treated with standard immunosuppressive therapy, i.e. tacrolimus, mycophenolic acid with or without steroids. Age was positively correlated with TNF-α expression in all three patient populations, and with IL-2 expression in healthy volunteers and kidney-transplant patients. Further age was correlated with inhibition of lymphocyte proliferation in healthy volunteers and with the T-cell activation marker CD25 in kidney-transplant patients. In healthy volunteers lymphocyte proliferation was higher in woman as compared to men. Other biomarkers of T-cell function were independent of the gender. In the kidney-transplant patient group a significantly lower expression of all biomarkers of T-cell functions compared to healthy volunteers and dialysis patients. In dialysis patients we found significant increased IL-2 expression compared to healthy volunteers, while the other T-cell functions were not significantly different. Further time on dialysis had no effect on the level of biomarker expression. In conclusion we found decreased T-cell functions in kidney-transplant patients compared to healthy volunteers and dialysis patients, increased IL-2 expression in dialysis patients compared to healthy volunteers and in all three populations we found a correlation of age and intra-T-lymphocyte TNF-α expression.  相似文献   
100.
Virosomes are reconstituted viral envelopes that can serve as vaccines and as vehicles for cellular delivery of various macromolecules. To further advance the use of virosomes, we developed a novel dialysis procedure for the reconstitution of influenza virus membranes that is easily applicable to industrial production and compatible with encapsulation of a variety of compounds. This procedure relies on the use of 1,2-dicaproyl-sn-glycero-3-phosphocholine (DCPC) as a solubilizing agent. DCPC is a short-chain lecithin with detergent-like properties and with a critical micelle concentration of 14 mM. DCPC effectively dissolved the influenza virus membranes after which the nucleocapsids could be removed by ultracentrifugation. The solubilized membrane components were reconstituted either by removal of DCPC by dialysis or by a procedure involving initial dilution of the solubilized membrane components followed by dialysis. Both protocols resulted in removal of 99.9% of DCPC and simultaneous formation of virosomes. Analysis of the virosome preparations by equilibrium sucrose density gradient centrifugation revealed co-migration of phospholipid and protein for virosomes produced by either method. Moreover, both virosome preparations showed morphological and fusogenic characteristics similar to native influenza virus. Size, homogeneity and spike density of the virosomes varied with the two different reconstitution procedures employed. The recovery of viral membrane proteins and phospholipids in the virosomes was found to be higher for the dilution/dialysis procedure than for the simple dialysis protocol. This novel procedure for the production of virosomes is straightforward and robust and allows further exploitation of virosomes as vaccines or as drug delivery vehicles not only in academia, but also in industrial settings.  相似文献   
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