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21.
目的:分析某医院SARS疫情的发生、发展及控制过程,为疫情控制提供一定的参考依据。方法:依照卫生部推荐的统一个案调查表和临床诊断标准,描述疫情的三间分布以及发放防护用品的数量与病例数的关系。结果:某医院疫情暴发曲线由3个暴发高峰组成,前两个峰较大,后一个峰较小,呈散发。提示病例传染共形成“三代”流行。结论:采用严密的综合防护措施,能够彻底控制SARS疫情在医院的暴发。  相似文献   
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23.
在青年学生中吸收优秀分子已成为高校党组织发展工作的重要组成部分,最近几年来,高中党建工作也不断发展。了解青年学生党建现状,更好地利用中学党建工作成果,提出了做好衔接工作的现实意义及对策措施。  相似文献   
24.
Summary We determined the effects of the N-methyl-Daspartate (NMDA) receptor blocker MK-801 (0.05, 0.1, and 0.5 mg/kg intraperitoneally, i.p.) and phenytoin (PHT, 5, 10, and 20 mg/kg i.p.) on flurothyl-induced clonic and tonic-clonic seizures in 9-, 1 5, 30-, and 60-day-old male rats. Both agents had seizure-, age-, and dose-specific effects. The highest dose of MK-801 was anticonvulsant against clonic flurothyl-induced seizures only in 9- and 60-day-old rats, but suppressed tonic-clonic seizures in all ages. The lowest dose of MK-801 (0.05 mg/kg) produced significant anticonvulsant effects only in 15 day old rats. PHT did not have any effect on clonic seizures throughout development. Both doses of PHT (10 and 20 mg/kg) were anticonvulsant against tonic-clonic seizures in adult rats but not in any other age group. The results indicate that NMDA receptors play an important role in tonic-clonic flurothyl-induced seizures throughout development (especially in 15-day-old rats) and that the anticonvulsant effects of PHT may vary at different stages of brain development.  相似文献   
25.
Women's life situation and experiences during pregnancy were prospectively studied in relationship to the development of congenital malformations (CMs) in their offspring, within samples of 84 offspring of pregnant index women with a history of nonorganic psychosis and 100 offspring of pregnant control women. Within both samples, offspring CMs were related to more problematic maternal life situations during pregnancy, the common denominator in these problems across samples being difficulties associated with the husband. Little relationship was found between CMs and the woman's own attitude toward the pregnancy or her mental condition during pregnancy. In both groups, total life situational problems and distress were more strongly related to the development of very minor CMs (termed "variants") than to the major, classical CMs.  相似文献   
26.
Bacterial resistance to antibiotics in community-acquired respiratory tract infections is a serious problem and is increasing in prevalence world-wide at an alarming rate. Streptococcus pneumoniae , one of the main organisms implicated in respiratory tract infections, has developed multiple resistance mechanisms to combat the effects of most commonly used classes of antibiotics, particularly the β -lactams (penicillin, aminopenicillins and cephalosporins) and macrolides. Furthermore, multidrug-resistant strains of S. pneumoniae have spread to all regions of the world, often via resistant genetic clones. A similar spread of resistance has been reported for other major respiratory tract pathogens, including Haemophilus influenzae , Moraxella catarrhalis and Streptococcus pyogenes . To develop and support resistance control strategies it is imperative to obtain accurate data on the prevalence, geographic distribution and antibiotic susceptibility of respiratory tract pathogens and how this relates to antibiotic prescribing patterns. In recent years, significant progress has been made in developing longitudinal national and international surveillance programs to monitor antibiotic resistance, such that the prevalence of resistance and underlying trends over time are now well documented for most parts of Europe, and many parts of Asia and the Americas. However, resistance surveillance data from parts of the developing world (regions of Central America, Africa, Asia and Central/Eastern Europe) remain poor. The quantity and quality of surveillance data is very heterogeneous; thus there is a clear need to standardize or validate the data collection, analysis and interpretative criteria used across studies. If disseminated effectively these data can be used to guide empiric antibiotic therapy, and to support—and monitor the impact of—interventions on antibiotic resistance.  相似文献   
27.
Metabolic pathways leading to lipid biosynthesis in four different developmental stages of Schistosoma mansoni were explored and quantified by incubation in the presence of labeled precursors in a chemically defined medium. At the schistosomulum stage and in male, female, or paired worms, glycerol and oleate incorporation into neutral lipids, mainly in the form of triacylglycerols, was greater than into phospholipids, whereas in 11-and 15-day-old worms, synthesis mainly led to phospholipids. Incorporation into phospholipids was recovered largely in phosphatidylcholine, and distribution into other phospholipids depended on the developmental stage. Incorporation of choline and ethanolamine into their respective phospholipids represented up to 15% of the parasitic phospholipid content. The formation of phosphatidylcholine by phosphatidylethanolamine methylation occurred mainly in the immature parasitic stages. Inositol incorporation was also measurable, whereas [14C]serine incorporation was low or undetectable. Addition of 1-palmitoyl-2-[14C]oleyl phosphatidylcholine revealed a very high uptake of this phospholipid by the immature stages but further metabolism was not detectable. In contrast, adult S. mansoni were completely unable to take up or absorb this exogenous phospholipid. The most striking aspect of this study was the relatively high metabolic activity in 11-day-old worms and the lower but sustained activity on day 15 and at the schistosomulum stage. By comparison, biosynthetic activity in adult S. mansoni, on which research studies have been focused until now, was very low. We also discuss the participation of lipid metabolism in the constant renewal of the membrane complex which is essential to parasitism by S. mansoni.  相似文献   
28.
David  Friedman  Lois  Putnam  Walter  Ritter  Marla  Hamberger  Steven  Herman 《Psychophysiology》1992,29(5):593-609
Event-related potentials were recorded in a developmental study of picture matching using an adaptation of Posner's (1978) letter-matching tasks. Subjects ranging in age from 6-39 were asked to decide whether two line drawings, presented sequentially, were the same or different on the basis of physical (physical identity), nominal (name identity), or categorical (category identity) criteria. The amplitude of a negativity at 400 ms (Neg400) increased as the number of dimensions on which the two line drawings differed increased. This effect held for all age groups, and was interpreted as reflecting the degree of semantic and/or physical relationship between the two pictures. However, one finding for Neg400 did suggest a qualitative difference in processing mode between the younger and older subjects. Both Neg400 and P3b latencies showed highly significant linear age trends, decreasing with increasing age. These age-related changes were interpreted as demonstrating quantitative speed of processing differences among age groups. The latencies of both Neg400 and P3b increased as the matching criteria became more complex. Moreover, P3b latency increased as the number of dimensions on which the two pictures differed increased, and this did not interact with age. Although both Neg400 and P3b showed age-related changes in scalp distribution, the fact that each was related to the experimental variables in similar fashion in all age groups suggested that they were homologous components across the age range studied. Taken as a whole, the data support continuity of information processing during these tasks across a wide age range.  相似文献   
29.

Introduction

MED13L-related intellectual disability is characterized by moderate intellectual disability (ID), speech impairment, and dysmorphic facial features. We present 8 patients with MED13L-related intellectual disability and review the literature for phenotypical and genetic aspects of previously described patients.

Materials and methods

In the search for genetic aberrations in individuals with ID, two of the patients were identified by chromosomal microarray analysis, and five by exome sequencing. One of the individuals, suspected of MED13L-related intellectual disability, based on clinical features, was identified by Sanger sequencing.

Results

All 8 individuals had de novo MED13L aberrations, including two intragenic microdeletions, two frameshift, three nonsense variants, and one missense variant. Phenotypically, they all had intellectual disability, speech and motor delay, and features of the mouth (open mouth appearance, macroglossia, and/or macrostomia). Two individuals were diagnosed with autism, and one had autistic features. One had complex congenital heart defect, and one had persistent foramen ovale. The literature was reviewed with respect to clinical and dysmorphic features, and genetic aberrations.

Conclusions

Even if most clinical features of MED13L-related intellectual disability are rather non-specific, the syndrome may be suspected in some individuals based on the association of developmental delay, speech impairment, bulbous nasal tip, and macroglossia, macrostomia, or open mouth appearance.  相似文献   
30.
大学生性行为及性道德观发展研究   总被引:6,自引:0,他引:6  
目的 了解当代大学生性行为及性道德观念的发展变化。方法 自制问卷,对全国9所高校的2000余名大学生进行调查,并用SPSS10.0对结果进行统计处理。结果 大学生性交行为发生率呈逐年上升趋势,且随年级上升而增加;大学生认可性交行为道德观的5个雏度,但各年级之间有差异;大学生边缘性行为和独自性行为发生率随年级显著上升,认可度也随年级增加而上升;大学生对同性性接触基本持排斥态度,但排斥态度则趋于下降。结论 大学生性行为和性道德随年级上升而明显变化,应加强学校教育和引导。  相似文献   
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