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121.
为探讨5-氟尿嘧啶的药效、毒性与给药剂量之间的关系,采用BALB/c小鼠来源的CT26结肠癌细胞株构建小鼠结肠癌模型,分别给予10、20、30和50 mg/kg剂量的5-氟尿嘧啶,分析其抗肿瘤效果、对小鼠体质量的影响和死亡率等指标.结果表明,5-氟尿嘧啶的体内抑瘤效果及毒性与剂量密切相关.综合分析评价各指标,认为20~30 mg/kg剂量的5-氟尿嘧啶较适合于小鼠结肠癌模型中的药效评价.  相似文献   
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In previous research, the economic impacts of temporary shutdowns of the Los Angeles–Long Beach harbors were simulated after a hypothetical terrorist attack, applying the National Interstate Economic Model to estimate state‐by‐state as well as interindustry impacts. However, the unpredictable characteristic of terrorist attacks might not be applicable to the case of a ports shutdown such as the one caused by the lockout of September–October 2002. Market participants can be expected to have contingency plans based on anticipations of a strike or shutdown. Can we identify any of these in terms of the use of alternate ports, in terms of alternate modes or even alternate time periods? The purpose of this study is to examine these questions. The approach is elaborated by testing for the possible effects of trade diversion to other West Coast ports, transportation modes, and intertemporal substitutions. We use data from WISERTrade describing commodity‐specific trade for the major West Coast ports before, during, and after the 11‐day shutdown of the fall of 2002. Shippers’ ability to divert trade is a key ingredient in the economy's ability to withstand attacks and disruptions. The work estimates the impacts on 47 industrial sectors across 50 states (and the District of Columbia).  相似文献   
124.
朝鲜时代的书院讲会产生于16世纪后半初期, 进入17世纪初期,成为书院讲学的主要方式,并形成一种制度。18世纪以后,书院教育中讲会的地位和作用得到了进一步强化。朝鲜时代的书院讲会基本上与明清时期中国书院的讲会大同小异,但还是从几个方面上有着各自不同的特点。  相似文献   
125.
The sonographic appearance of intraabdominal abscess, excluding prostatic abscess, is presented. The most common sonographic pattern identified for intraabdominal abscess is an irregularly defined, hypoechoic mass with minimal to no through transmission. Definitive diagnosis of intraabdominal abscess using only sonography is not possible, as variations of this common sonographic pattern are imaged. Sonography is best utilized to scan an animal when there is a high suspicion of intraabdominal abscess with no overt physical or radiographic evidence, and to better characterize intraabdominal masses. Sonography can be used to assist in percutaneous aspiration, catheterization, and intraoperative localization of abscessation.  相似文献   
126.
This study was conducted to investigate the efficacy of rocuronium bromide as mydriatic agent in domestic pigeons (Columba livia). This study was done in two phases. In the first phase, rocuronium bromide (0.20 mg/20 µl) was topically instilled to the right eye (OD) of eight domestic pigeons. Pupil diameter was measured before instillation (T0), and at 5 (T05) and 10 (T10) min after instillation, and every 10 min thereafter until 160 (T160) min. Pupillary light reflex (PLR) was assessed using a scoring system at the same time points. In the second phase, the same dosage was instilled twice in the span of 10 min into both eyes (OU) of four pigeons (eight eyes). Measurements were done accordingly. The iris color in the first phase were: gravel, pearl and bull eye. All irises in the second phase were bull eye. Mydriasis were observed in 6/8 (75%) pigeons in the first phase. Maximal mydriasis was observed at T30 (mean pupil diameter=4.62 ± 0.13 mm). Pupil diameter in the treated eye was significantly different from contralateral eye and from T0 since T05 (P=0.017 and P=0.006, respectively)−T120 (P=0.043 and P=0.044, respectively). PLR was disappeared from T10 (P=0.034) to T90 (P=0.041). In the second phase, mydriasis was only observed in 2/8 eyes. This study suggested that rocuronium bromide was able to produce mydriasis in pigeons other than bull eye iris.  相似文献   
127.
Taste effects of oligopeptides in a Vietnamese fish sauce   总被引:4,自引:0,他引:4  
ABSTRACT: A Vietnamese fish sauce Nuoc mam used in the present study was rich in oligopeptides of which nitrogen content accounted for 20% of total nitrogen. The high-molecular-weight peptide fractions fractionated by ion-exchange chromatographies and ultrafiltration enhanced sweetness and umami as well as sourness and bitterness of the fish sauce, and increased several flavor characteristics including continuity, first taste and aftertaste. Thus, it is apparent that large amounts of peptides produced during the long-term fermentation of fish sauce are responsible for the complicated taste of the sauce. From each fraction, 17 peptides in total were isolated and determined for their amino acid sequences. These di-, tri- and tetra-peptides synthesized by solid- or liquid-phase method gave any one of bitter, sour, umami taste, or practically no taste in the absence of salt. In the presence of 0.3% NaCl, however, almost all peptides showed sweet and umami tastes. Other than these 17 peptides, there existed many other kinds of peptides in the fish sauce. Thus, these peptides are thought to contribute to the overall taste of the fish sauce.  相似文献   
128.
Rodent models of focal cerebral ischemia that do not require craniotomy have been developed by intraluminal suture middle cerebral artery occlusion (MCAo). Mouse MCAo models have been widely used and extended to genetic studies of cell death or recovery mechanisms. Therefore, we compared surgery-related parameters and techniques between such rats and mice. In rodent MCAo models, has to be considered body temperature during the operative period, as well as the need for the use of a standardized tip in terms of the outer diameter of probes. Induction of focal cerebral ischemia was measured by neurological dysfunction parameters. Our methods could induce stable moderate-severity ischemic brain injury models and histological alteration at 24 hr after MCAo surgery. Moreover approximately 80% (rats) and 85% (mice) survival ratios were shown indicating with model engineering success. Finally, we described and compared major parameters between rats and mice, including probe size, thread insert length, operation and occlusion periods, and differences in the procedures.  相似文献   
129.
The prevalence of resistant genes against β-lactams in 119 Aeromonas strains was determined. A large number (99.2%) of the present fish strains were resistant to one or more β- lactams including ceftiofur, amoxicillin-clavulanic acid, ampicillin, piperacillin and cefpodoxime. Among antibiotic resistance phenotypes, the simultaneous resistance to all β-lactams occurred in 25.2% (n=30) of all strains, which consisted of 18 strains of A. dhakensis, 8 strains of A. caviae, 2 strains of A. hydrophila and only one strain of A. veronii. For exploring genetic background of the antibiotic resistances, multiple PCR assays were subjected to detect β-lactamase-encoding genes, blaTEM, blaOXA-B and blaCTX-M. In the results, the blaTEM-1 gene was harbored in all strains, whereas only 3 strains harbored blaOXA gene. In the case of blaCTX-M gene, the gene was detected in 21.0% (25 out of 119) of all strains, which countered with 80% (20 out of 25) of A. dhakensis, 8% (2 out of 25) of A. caviae and 12% (3 out of 25) of A. hydrophila. In addition, most of the blaCTX-M positive strains showed simultaneous resistance to all β-lactams (18 out of 30 strains). In sequence analysis for blaCTX-M genes detected, they were CTX-M group 1-encoding genes including blaCTX-M-33 from 3 eel strains of A. dhakensis. Therefore, A. dhakensis obtained from cultured fish could represent a reservoir for spreading genes encoding CTX-M group 1 enzymes and hence should be carefully monitored, especially for its potential risk to public health.  相似文献   
130.
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