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排序方式: 共有1249条查询结果,搜索用时 234 毫秒
51.
目的:探究适宜的人纤维蛋白原制剂中蛋白质含量测定方法。方法:分别应用《中国药典》三部(2010年版)中蛋白质测定法项下三氯醋酸沉淀法和两种改良后的三氯醋酸法测定6批人纤维蛋白原制剂中的蛋白质含量,比较三种方法的稳定性和平行性。结果:改良后的三氯醋酸沉淀2法[用三氯醋酸代替《中国药典》三部(2010年版)钨酸钠沉淀法中钨酸钠和硫酸溶液]的稳定性和平行性明显比《中国药典》三部(2010年版)中蛋白质测定法项下三氯醋酸沉淀法和改良后的三氯醋酸沉淀3法更好,相对标准偏差(RSD)更低。结论:改良后的三氯醋酸沉淀2法更适合人纤维蛋白原制剂中蛋白质含量的测定。 相似文献
52.
GEIR TRYGGVASON BYLGJA HILMARSDOTTIR GUðMUNDUR H. GUNNARSSON JÓN JÓHANNES JÓNSSON JÓN G. JÓNASSON MAGNÚS K. MAGNÚSSON 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2010,118(9):648-656
Tryggvason G, Hilmarsdottir B, Gunnarsson GH, Jónsson JJ, Jónasson JG, Magnússon MK. Tyrosine kinase mutations in gastrointestinal stromal tumors in a nation‐wide study in Iceland. APMIS 2010; 118: 648–56. Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. It is characterized by activating mutations in the tyrosine kinase genes c‐kit or PDGFRA. This study examined the mutation rate and type in a population‐based material. All gastrointestinal mesenchymal tumors over the years 1990–2004 were evaluated and GIST tumors identified using immunohistochemistry (c‐kit) and conventional pathologic parameters. Paraffin sections from all tumors were subjected to mutation analysis on exons 9, 11, 13 and 17 of the c‐kit gene and exons 12 and 18 of the PDGFRA gene. To screen for mutations, we used a highly sensitive conformation‐sensitive gel electrophoresis (CSGE) and to define the mutated alleles, we employed direct automated DNA sequencing. All c‐kit‐positive gastrointestinal mesenchymal tumors were entered into the study. Fifty‐six tumors from 55 patients were analyzed. Mutations were found in 52 tumors representing a 92.9% mutational rate. Most of the mutations were found in c‐kit exon 11 (76.8%), followed by c‐kit exon 9 (10.7%). PDGFRA mutations were only found in three tumors. No correlation of mutation type with biologic behavior was found. This population‐based study, using a sensitive CSGE method, identifies mutations in the great majority of patients with GIST. 相似文献
53.
Sexual offences are recognized to be one of the most critical of crimes throughout the world. In Turkey, forcible rapes show, in the sexual crime rates, an increase of approximately 3% every year. It becomes even more critical, when realizing that less than half of all rapes, which are believed to occur, are reported to law enforcement, and of those few assailants who are arrested even fewer are convicted of rape. Often, little or no knowledge of the correct methods of locating, recovering, packaging, and preserving evidence specimens are the causes for compromising the forensic examination in court. This problem occurs when medical personnel are not adequately trained or properly advised in the evidentiary aspects and medical features of treating a victim. 相似文献
54.
Mayu Isotani Osamu Yamada Joshua L. Lachowicz Kyoichi Tamura Hiroko Yagihara Yasuhito Fujino Kenichiro Ono Tsukimi Washizu Makoto Bonkobara 《British journal of haematology》2010,148(1):144-153
The purpose of the current study was to investigate the mutation status of KIT in feline mast cell tumours (MCTs) and to examine the effects of tyrosine kinase inhibition on the phosphorylation of mutant kit in vitro and in clinical cases of cats. Sequence analysis of KIT identified mutations in 42/62 MCTs (67·7%). The vast majority of the mutations were distributed in exons 8 and 9, both of which encode the fifth immunoglobulin-like domain (IgD) of kit. All five types of kit with a mutation in the fifth IgD were then expressed in 293 cells and examined for phosphorylation status. The mutant kit proteins showed ligand-independent phosphorylation. The tyrosine kinase inhibitor imatinib mesylate suppressed the phosphorylation of these mutant kit proteins in transfectant cells. In a clinical study of 10 cats with MCTs, beneficial response to imatinib mesylate was observed in 7/8 cats that had a mutation in the fifth IgD of kit in tumour cells. Mutations in the fifth IgD of kit thus appear to be common and potentially sensitive to imatinib mesylate in feline MCTs. These data provide an in vivo model for paediatric mastocytosis where mutations in the fifth IgD of kit also occur. 相似文献
55.
Gregory A. Sacha William J. Schmitt Steven L. Nail 《Pharmaceutical development and technology》2013,18(2):195-205
The physical-chemical processing variables affecting particle size following precipitation using the supercritical antisolvent (SAS) method were investigated by varying both the composition of the feed solvent and the structure of the solute, using a series of steroids. The key factor influencing particle size in these studies appears to be the solubility of the drug in the organic solvent/supercritical fluid mixture, where relatively high solubility causes a lower degree of supersaturation in the precipitation vessel, resulting in a relatively large particle size. Higher operating pressures result in larger particle sizes, probably through the effect of pressure on solubility. Physical properties of the carrier solvent, such as vapor pressure and dielectric constant, were not effective predictors of relative particle size of the precipitated powder, nor was solubility of the model drug in the carrier solvent. In limited studies of the physical state of the precipitated solid, higher apparent crystallinity was observed for powders with larger particle size. A precipitate of a different crystal form was observed when starting with hydrocortisone hemisuccinate monohydrate and may represent the loss of water of hydration. An amorphous solid was precipitated when starting with yttrium acetate dihydrate. Broad guidelines for effective particle size reduction using this technique are presented. 相似文献
56.
Natural and technical factors in faecal contamination incidents of drinking water in small distribution networks, France, 2003-2004: a geographical study 下载免费PDF全文
《Journal of water and health》2011,8(1):20-34
This geographical study aimed to show natural or water-processing-related factors of faecal contamination incidents (FCIs) of drinking water in continental France. We defined a FCI as the occurrence of at least 20 colony-forming Escherichia coli or enterococci among all the 100 mL samples collected for regulatory purpose within one day from a given drinking water supply zone (SZ). We explored correlations between the standardized number of FCIs per département (N_Pols) and various indicators related to weather, land cover, topography, geology and water management for three SZ size sub-classes. In 20032004, 2,739 FCIs occurred in SZs supplying fewer than 2,000 people, mainly with simply disinfected groundwater. N_Pols correlates with four covariates: (1) precipitation; (2) the extension of the karst outcrops; (3) the extent of disinfection; and (4) catchment protection. One hundred millimetres of yearly excess in precipitation increases the pollution risk by 2837%, depending on the sub-class. A 10% extension of the karst areas, a 10% increase of unprotected resources, or of SZs with no disinfection, could entail a higher risk of FCI by about 10%. The correlations are reproducible over the three sub-classes and corroborate expert appraisals. These results encourage the ongoing effort to generalize disinfection and catchment protection. 相似文献
57.
Materials Editorial Office 《Materials》2014,7(11):7583-7614
This article reviews the recent advances and challenges in the preparation of polymer/inorganic hybrid nanoparticles. We mainly focus on synthetic strategies, basing our classification on whether the inorganic and the polymer components have been formed in situ or ex situ, of the hybrid material. Accordingly, four types of strategies are identified and described, referring to recent examples: (i) ex situ formation of the components and subsequent attachment or integration, either by covalent or noncovalent bonding; (ii) in situ polymerization in the presence of ex situ formed inorganic nanoparticles; (iii) in situ precipitation of the inorganic components on or in polymer structures; and (iv) strategies in which both polymer and inorganic component are simultaneously formed in situ. 相似文献
58.
目的探讨一次性麻醉穿刺包与普通腹腔穿刺包在腹腔化疗中应用效果。方法将2008年6月-2009年4月住院的胃癌和卵巢癌行腹腔化疗的患者53例,随机分为两组。实验组29例,用一次性麻醉穿刺包行腹腔穿刺化疗;对照组24例,用普通腹腔穿刺包行腹腔穿刺化疗;比较两组患者应用不同穿刺包行腹腔穿刺化疗的并发症比较。结果实验组并发症发生率明显低于对照组(P〈0.05)。结论一次性麻醉穿刺包应用于腹腔化疗中操作简便、创伤小、并发症少,患者乐于接受等优点,值得在临床上推广使用。 相似文献
59.
目的优化提取钉螺线粒体基因组DNA(mt DNA)的方法。方法应用高温裂解、蛋白酶K变温消化和醋酸钾纯化对传统的高盐沉淀法进行优化,并将优化的高盐沉淀法与蔗糖密度梯度离心法、传统的高盐沉淀法进行比较。用紫外分光光度计、琼脂糖凝胶电泳和线粒体COX1基因PCR扩增产物鉴定提取的mt DNA,并用核ITS基因PCR扩增产物检测有无核DNA污染。结果优化的高盐沉淀法获得的mt DNA浓度和产量较高,差异有统计学意义(F=3 032.65、10185.00,P均0.01)。用凝胶电泳检测后未发现核DNA与蛋白质污染,质量可满足于PCR、测序等分子生物学研究。结论优化的高盐沉淀法简易高效,成本低,获得的mt DNA能满足相关分析要求。 相似文献
60.
目的:制备多壁碳纳米管/羟基磷灰石/壳聚糖复合温敏凝胶,探讨其作为拔牙位点保存材料的理化性能。方法:采用原位沉积方法制备多壁碳纳米管/羟基磷灰石(MWNT/ HA简称HAC)复合无机材料,将其分散至壳聚糖温敏凝胶中,制备壳聚糖/多壁碳纳米管/羟基磷灰石(CS /MWNT/HA简称CS/HAC)复合温敏凝胶,以成胶时间、孔径、孔隙率、机械强度及降解性能为指标优化配方设计,并表征复合温敏凝胶的微观形貌及理化性能。结果:以10 g/L的HAC作为补强成分加入到壳聚糖溶液中,能够在不影响成胶并保证一定孔隙率(84%)的前提下,提高材料的机械性能(抗压强度0.441 MPa),所获复合温敏凝胶具有适宜的临床操作时间(12 min),并具有可控的降解速率。结论:负载HAC的复合温敏凝胶具有良好的成型性,并具有较好的机械性能,在拔牙位点保存领域具有良好的应用前景。 相似文献