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81.
The role of pH in determining the environmental fate of [14C]aldicarb was examined in an aquatic microcosm. Only minor amounts of the radiochemical were absorbed by aquatic organisms at any pH. Of the radioactivity absorbed, greater than 75% was rapidly metabolized and incorporated into tissues. Minor differences in the in vivo spectrum of aldicarb and metabolites as a function of pH were discerned for fish; the quantitative and qualitative distribution of aldicarb and its metabolites was identical for the other organisms across the pH levels. The most notable difference in metabolite spectrum appearing in the water as a function of pH was the absence of aldicarb sulfone at pH 4 on Day 6. In contrast, aldicarb sulfoxide was found as the major metabolite and aldicarb was completely lacking at all three pH levels. Since aldicarb sulfoxide is biologically active, disappearance of the parent compound does not eliminate hazard. The general effects of pH on the environmental fate of aldicarb are negligible on Day 6 but may be more pronounced at other time periods. 相似文献
82.
This report describes procedures to culture 1- to 2-mm-thick cross sections of lung lobes for periods of 4 to 6 weeks. Normal morphologic and macromolecular composition are maintained. Previous attempts to maintain adult peripheral lung cultures for periods beyond 7-10 days or to examine respiratory disorders in vitro other than acute changes have been generally unsuccessful. Eight different, supplemented, serum-free media, mixed with heated liquid agarose were infused into the airways of hamster and rat lungs. Cross sections were explanted onto squares of porous surgical packing material, placed in medium, and incubated for 4 to 6 weeks. The ability of each medium to maintain normal lung was assessed microscopically by quantitative image analysis and by biochemical analyses. The optimal medium formulation for each species is described. The adult peripheral lung culture system may provide toxicologists with a unique model for mechanistic and safety evaluations of potential lung toxicants. 相似文献
83.
D. McArthur C. Peek-Asa T. Webb K. Fisher B. Cook N. Browne J. Kraus 《Injury prevention》2000,6(2):120-124
OBJECTIVES: The purpose of this study was to evaluate the seriousness and frequency of violence and the degree of associated injury depicted in the 100 top grossing American films of 1994. METHODS: Each scene in each film was examined for the presentation of violent actions upon persons and coded by means of a systematic context sensitive analytic scheme. Specific degrees of violence and indices of injury severity were abstracted. Only actually depicted, not implied, actions were coded, although both explicit and implied consequences were examined. RESULTS: The median number of violent actions per film was 16, with a range from 1 to 110. Intentional violence outnumbered unintentional violence by a factor of 10. Almost 90% of violent actions showed no consequences to the recipient's body, although more than 80% of the violent actions were executed with lethal or moderate force. Fewer than 1% of violent actions were accompanied by injuries that were then medically attended. CONCLUSIONS: Violent force in American films of 1994 was overwhelmingly intentional and in four of five cases was executed at levels likely to cause significant bodily injury. Not only action films but movies of all genres contained scenes in which the intensity of the action was not matched by correspondingly severe injury consequences. Many American films, regardless of genre, tend to minimize the consequences of violence to human beings. 相似文献
84.
The purpose of this study is to assess the prognostic abilities of the fourth and fifth edition International Union Against Cancer (UICC) staging systems for nasopharyngeal carcinoma (NPC) in Australian patients. All patients planned for curative treatment at the Peter MacCallum Cancer Centre from April 1985 to December 1999 were included in this study. There were 181 patients eligible for this study. The median follow up was 7.6 years. Histological subgroups were World Health Organization (WHO) 1 (23), WHO 2 (12), and WHO 3 (146). Presentation with stage IV disease was 83% by UICC fourth edition staging and 34% by UICC fifth edition staging. The 5 years failure-free survival (FFS) rates for stage 1, 2, 3 and 4 disease by the fourth edition was 77, 100, 93, and 49% respectively,and by the fifth edition was 85, 76, 57 and 36%, respectively. The 5 years overall survival (OS) for stage 1, 2, 3, and 4 disease by the fourth edition was 77, 100, 100 and 61%; respectively, and by the fifth edition was 85, 82, 67 and 53%, respectively. Stage 4 patients by the fourth edition were reclassified as stages 2, 3 and 4 by the fifth edition with hazard ratios of 0.77, 1.01 and 1.79, respectively. In multifactor analysis, the fifth edition staging system was significantly related to FFS and OS after allowing for the fourth edition (FFS: P = 0.002; OS: P = 0.005), but the fourth edition was not significantly related to FFS or OS after allowing for the fifth edition (FFS: P = 0.96; OS: P = 0.96). This study confirms the prognostic superiority of the fifth edition UICC staging system over the fourth edition staging system in an Australian NPC population. 相似文献
85.
Gilbert ME McLanahan ED Hedge J Crofton KM Fisher JW Valentín-Blasini L Blount BC 《Toxicology》2011,283(1):41-48
Severe iodine deficiency (ID) results in adverse health outcomes and remains a benchmark for understanding the effects of developmental hypothyroidism. The implications of marginal ID, however, remain less well known. The current study examined the relationship between graded levels of ID in rats and serum thyroid hormones, thyroid iodine content, and urinary iodide excretion. The goals of this study were to provide parametric and dose-response information for development of a quantitative model of the thyroid axis. Female Long Evans rats were fed casein-based diets containing varying iodine (I) concentrations for 8 weeks. Diets were created by adding 975, 200, 125, 25, or 0 μg/kg I to the base diet (∼25 μg I/kg chow) to produce 5 nominal I levels, ranging from excess (basal + added I, Treatment 1: 1000 μg I/kg chow) to deficient (Treatment 5: 25 μg I/kg chow). Food intake and body weight were monitored throughout and on 2 consecutive days each week over the 8-week exposure period, animals were placed in metabolism cages to capture urine. Food, water intake, and body weight gain did not differ among treatment groups. Serum T4 was dose-dependently reduced relative to Treatment 1 with significant declines (19 and 48%) at the two lowest I groups, and no significant changes in serum T3 or TSH were detected. Increases in thyroid weight and decreases in thyroidal and urinary iodide content were observed as a function of decreasing I in the diet. Data were compared with predictions from a recently published biologically based dose-response (BBDR) model for ID. Relative to model predictions, female Long Evans rats under the conditions of this study appeared more resilient to low I intake. These results challenge existing models and provide essential information for development of quantitative BBDR models for ID during pregnancy and lactation. 相似文献
86.
目的:急性冠状动脉综合征(ACS)置入支架患者使用盐酸替罗非班、阿司匹林、氯吡格雷、低分子肝素(四联)时,评价泮托拉唑对消化道的保护作用.方法:选择ACS置入支架治疗的患者266例,随机分入观察组134例,对照组132例,所有患者均服用阿司匹林、氯吡格雷、低分子肝素和盐酸替罗非班.观察组患者静脉注射泮托拉唑40 mg/d 4~5天,之后改为泮托拉唑片剂40 mg/次,2次/天,服用30天.观察两组间30天全因死亡、再次心肌梗死、再次经皮冠状动脉介入治疗(PCI)、再次住院、颅内出血和消化道出血状况.结果:观察组134例患者30天内全因死亡5例、再次心肌梗死4例、再次PCI4例和再次住院8例;对照组132例患者分别为8例、6例、5例和13例,两组相比差异均无统计学意义(P>0.05);两组均无颅内出血发生.观察组消化道大出血0和总消化道出血事件3例,对照组分别为5例和15例,两组比较观察组消化道大出血和总消化道出血事件少于对照组(P<0.05),差异均有统计学意义.结论:ACS置入支架治疗的患者,盐酸替罗非班治疗是安全有效的,未见颅内出血发生.静脉注射和口服泮托拉唑并不增加30天全因死亡、再次心肌梗死、再次PCI和再次住院发生,同时可以减少30天内消化道出血发生率特别是消化道大出血事件的发生,具有良好的消化道保护作用和安全性. 相似文献
87.
Emily M. Fortin Jerry Fisher Sheng Qiu Charlene Irvin Babcock 《Emergency radiology》2016,23(6):597-601
Previous studies suggest overuse disparity of head computed tomography (CT) in white pediatric trauma patients with minor head injuries. Our study is meant to determine if race or insurance status impacts the probability of obtaining head CT in patients with a Glasgow Coma Scale (GCS)?=?15. Using the 2008–2010 National Hospital Ambulatory Medical Care Survey for Emergency Departments (NHAMCS) database, the following variables were analyzed: race, emergency medical services (EMS) arrival, triage category, admission status, gender, age, and insurance status. Patients with injuries were excluded. All patients included had GCS?=?15. In univariate analysis, head CT is more likely to be obtained for patients in the following categories: Medicare insured, private insurance, Medicaid insured, and self-pay, EMS arrival, triage category immediate, and age >75 years. In logistic regression, race (white vs. black) was no longer significant, but there was disparity based on insurance status with privately insured patients more likely to receive a head CT (OR?=?1.683, 95 % CI?=?1.255–2.259). After controlling for the above inclusion variables and focusing on patients less likely to need CT (non-traumatic with GCS?=?15), privately insured patients were more likely to receive a head CT compared with uninsured. Race alone was not associated with an increased probability of receiving a head CT. 相似文献
88.
89.
张振 《世界核心医学期刊文摘》2006,2(5):8-9
背景:在英国,已知儿童期肥胖的社会经济梯度变化曲线在入学年龄时已存在,这一梯度变化曲线的起因目前尚不清楚,但很可能归咎于日常体力活动、静坐行为和膳食摄入上的社会经济差别。目的:验证苏格兰幼童的日常体力活动和(或)静坐行为与社会经济状态(SES)有关这一假说。方法:通过 相似文献
90.