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991.
Wajih N  Hutson SM  Wallin R 《Blood》2006,108(12):3757-3760
To improve production of functional fully gamma-carboxylated recombinant human clotting factor IX (r-hFIX), cell lines stably overexpressing r-hFIX have been engineered to also overexpress proteins of the gamma-carboxylation system. Here we demonstrate that siRNA silencing of calumenin, an inhibitor of the gamma-carboxylation system, enhances production of functional r-hFIX produced by engineered BHK21 cells. The production yield of functional r-hFIX was 80% in engineered cells where calumenin had been silenced 78%. We propose that this high-yield expression system can easily be adapted to overproduce functional forms of all members of the vitamin K-dependent protein family.  相似文献   
992.
993.
We used computed tomography to detect and localize foreign bodies in two unusual cases of penetrating injury to the eyes. In one case, a large broken twig appeared to have penetrated the globe and the inferior rectus muscle; in the other, the globe was ruptured by many glass shards . In the first case surgery showed the computed tomographic impression to be incorrect. The globe and the inferior rectus muscle were intact and vision and motility were normal postoperatively. In the second case, swelling made direct visualization impossible, and computed tomography was used to locate the foreign bodies.  相似文献   
994.
Summary and Conclusions The average serum copper in the control group in the present study was 175±45.5 μgm% (range 88–220 μgms%). In a group of 15 cases of infantile cirrhosis, the mean value of serum copper was 452 μgm%. A mean level of 477 μgm% (range 416–556 μgm%) was found in 5 cases of infective hepatitis. Mean copper level in 25 cases of icterus neonatorum was 373 μgm% (range 220–860 μgm%). Factors contributing towards hypercupraemia are: Liver cell damage or immaturity, hyperglobulinaemia, biliary obstruction, anaemia and a rapid breakdown of red blood cells. From the Department of Pediatrics, M.G.M. Medical College and M.Y. Hospital, Indore.  相似文献   
995.
Values (%) for true digestibility (TD) of protein and individual amino acids in some vegetable proteins were determined by the rat balance (fecal) method. Diets containing 8% crude protein (N X 6.25) from soaked and autoclaved samples of Trapper and Century field peas, lentil, pinto bean, seafarer bean, black bean or fababean and autoclaved samples of soybean, peanut, sunflower, rolled oat, rice + soybean and corn + pea were tested in two rat balance studies. In the case of blends, each protein source provided 50% of total protein. The beans, peas and lentil proteins were limiting in sulphur amino acids, tryptophan and threonine, whereas sunflower and rolled oat were most limiting in lysine. In beans, peas and lentil, the TD values of methionine (51-82), cystine (46-85), tryptophan (47-90) and threonine (62-84) were considerably lower than the TD values of total nitrogen (72-90). Similarly, in sunflower and rolled oat, the TD values of lysine (81-83) were lower than the TD values of total nitrogen (90-91). These data suggested that crude protein digestibility may not be a good predictor of bioavailability of limiting amino acids in vegetable proteins. Amino acid scores of the vegetable proteins were 62-96%. The corrections for true digestibility of protein and individual amino acids lowered the scores by 6-15 and 11-47 percentage units, respectively.  相似文献   
996.
AIM: To evaluate the determinants of sonographic measurements of pyloric length and muscle thickness in infants with hypertrophic pyloric stenosis (HPS) and to determine whether infants born prematurely have proportionately smaller measurements. MATERIALS AND METHODS: A retrospective review was carried out of 190 infants operated on for HPS at Bristol Children's Hospital over a 5-year period. Sonographic measurements of pyloric length and muscle thickness were related to age, history of prematurity, weight, sex and family history of HPS. RESULTS: Pyloric length in infants with HPS was significantly greater in those born at term compared to those born prematurely (18.6 mm [SD 2.2] vs 17.3 mm [SD 3.1], P = 0.043); this was explainable by body weight, with length increasing by 1.13 mm (SE 0.35) per kilogram (P = 0.002). There was no significant relationship with measured muscle thickness. CONCLUSION: Sonographic measurement of pyloric length is strongly correlated with the weight of the infant, irrespective of other factors. The relationship of length and weight may be useful in confirming the presence of HPS in small and premature infants.  相似文献   
997.
BACKGROUND AND PURPOSE: Although neuropsychological symptoms and signs are common in thyroid disease, their organic substrate is unknown. We performed brain MR imaging in patients with hyperthyroidism or hypothyroidism before and after treatment and correlated the results with hormonal markers. METHODS. Eight patients with hyperthyroid disease and three with hypothyroid disease underwent imaging within 1-2 days of a thyroid hormone testing. Images were registered, and brain and ventricular sizes were measured by using a semiautomated contour and thresholding technique. Changes in brain and ventricular volume were correlated with serum levels of total thyroxine (T(4)), unbound triiodothyronine (free T(3)), and thyroid-stimulating hormone (TSH) before and after treatment. RESULTS. With treatment, brain size decreased by 6,329-31,183 mm(3) in the hyperthyroid group and increased by 2,599-48,825 mm(3) in the hypothyroid group. Conversely, with treatment, ventricular size increased by 325-6,279 mm(3) in the hyperthyroid group and decreased by 760-2,376 mm(3) in the hypothyroid group. There was a highly significant correlation between reduction in brain size and reduction in T(4), as well as between the increase in ventricular size and reduction in T(4). There was a significant correlation between reduction in ventricular size and reduction in free T(3). There were highly significant correlations between reduced levels of TSH and increase in brain size, as well as between increased levels of TSH and increase in ventricular size. CONCLUSION. In thyroid disease, the size of the brain and ventricles significantly change after treatment, and these changes are correlated with T(4), free T(3), and TSH levels. The mechanism of these changes is uncertain, but it may involve osmolyte regulation, the sodium and water balance, and alterations in cerebral hemodynamics.  相似文献   
998.
Despite major advances in HIV research, eradication of HIV from the body is not yet possible. However, current antiretroviral (ARV) therapy can achieve disease control via viral suppression below the limits of detection of currently available assays. This has led to a marked decline in morbidity and mortality associated with the development of opportunistic infections and malignancies. Since viral suppression appears to be the most achievable goal of current therapy, there arises a need for new and more potent ARV agents in order to maintain viral suppression. Many of the currently available protease inhibitors (PIs) have a high protein-binding ability, short plasma half-life [1] and pharmacokinetic interactions with food or other drugs [2]. This can result in sub-optimal plasma drug concentrations, which may allow the virus to break through and replicate, leading to the development of resistant mutants [1]. Lopinavir/ritonavir (LPV/r; Kaletra, Abbott Laboratories) is a new PI consisting of a co-formulation of lopinavir and low-dose ritonavir. The sub-therapeutic dose of ritonavir (a potent cytochrome P450 [CYP] 3A4 inhibitor) inhibits the metabolism of lopinavir, resulting in higher lopinavir concentrations than when lopinavir is administered alone [3]. This pharmacokinetic interaction is associated with a high lopinavir trough level:wild type median effective concentration (EC(50)) ratio and good general tolerability when compared with other currently licensed PIs [4]. The concept of pharmacokinetic enhancement - boosting - is not new as ritonavir has previously been utilised in this context with other PIs. The relationship between plasma and intracellular drug levels has yet to be clarified. What has been ascertained from pharmacokinetic studies thus far is the correlation between ARV trough plasma concentrations (C(min)) and virological outcome [5,6]. LPV/r exemplifies how the pharmacokinetic profile of a drug can be modified to attain sufficient C(min) to suppress pheno- and genotypically resistant viral strains, as well as provide a pharmacological barrier to the emergence of resistance [7]. LPV/r reduces pill-burden and aids compliance, as shown by encouraging results in the treatment of both ARV-naive and -experienced patients.  相似文献   
999.
1000.
EPR oximetry is a promising, relatively non-invasive method for monitoring the partial pressure of oxygen in tissue (PtO2) that has proved useful in following changes under various physiologic and pathophysiologic conditions. Optimal utilization of the method will be facilitated by systematic comparisons with other available methods. Here we report on the absolute values of rat brain PtO2 using EPR and the more widely used Eppendorf polarographic microelectrode system in the same brain. EPR used an L-band (1.2 GHz) spectrometer and implanted lithium phthalocyanine (LiPc) as the oxygen-sensitive paramagnetic material. Eppendorf measurements were made by a needle probe moved vertically through the cortex at 0.5 mm intervals in three tracks including one adjacent to the location of the LiPc. Several conclusions were drawn, including, (1) the average PtO2 measured by the two methods was similar but EPR reported a significantly higher average PtO2, (2) there was poor correlation between the values in the same animal on the same side of the brain, (3) the Eppendorf reported a larger range of values and (4) the heterogeneity of oxygen levels in the brain and the areas sampled by the two methods provide an adequate explanation for the observed differences.  相似文献   
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