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101.
Industrial conditions which utilize temperature, pressure, and carbon monoxide in the presence of metal catalysts are conducive to metal carbonyl formation. An evaluation of the thermodynamic equilibrium data associated with metal carbonyls shows a definite relationship between these parameters which allow us to construct nomographs concerning their equilibrium formation. Metal carbonyls represent a distinct medical hazard. Recommendations for safe exposure limits and safety devices for personnel protection are based on the toxicity associated with metal carbonyls. Analytical methods indicate that adequate monitoring of the carbonyls of nickel, cobalt, and iron can be obtained.  相似文献   
102.
牙科医生对口腔卫生服务体系的评价   总被引:1,自引:0,他引:1  
目的 :分析牙科医生的日常工作量和牙医对口腔卫生服务的态度评价 ,有助于口腔卫生服务体系的制定和评价。方法 :根据武汉市卫生部门登记在册的牙科医生 ,采用整群抽样的方法随机选择 2 5 0名牙科医生进行开放式问卷调查。结果 :所调查的 2 5 0名样本中 ,5 2 %为女性 ,牙科医生平均工作年限为 11.6年 ,平均使用 0 .8台牙椅 ,每位牙医平均每天看 15个病人。主要工作时间用于充填治疗和拔牙。 93 %的牙医认为中国口腔卫生服务强调治疗而忽视预防保健。结论 :口腔卫生服务应重视口腔预防保健  相似文献   
103.
What is the physiological function of mast cells?   总被引:8,自引:0,他引:8  
Under physiological conditions, skin mast cells preferentially localize around nerves, blood vessels and hair follicles. This observation, which dates back to Paul Ehrlich, intuitively suggests that these enigmatic, multifacetted protagonists of natural immunity are functionally relevant to many more aspects of tissue physiology than just to the generation of inflammatory and vasodilatory responses to IgE-dependent environmental antigens. And yet, for decades, mainstream-mast cell research has been dominated by a focus on the -undisputedly prominent and important - mast cell functions in type I immune responses and in the pathogenesis and management of allergic diseases. Certainly, it is hard to believe that the very large and rather selectively distributed number of mast cells in normal, uninflamed, non-infected, non-traumatized mammalian skin or mucosal tissue simply hanging around there lazily day and night, just wait for the odd allergen or parasite-associated antigen to come by so the mast cell can finally swing into action. Indeed, the past decade has witnessed a renaissance of mast cell research 'beyond allergy', along with a more systematic exploration of the surprisingly wide range of physiological functions that mast cells may be involved in. The current debate sketches many exciting horizons that have recently come into our vision during this intriguing, ongoing search.  相似文献   
104.
105.
目的 探讨MSCT对食管鱼刺异物的检出率及临床诊断价值.方法 实验组:取3种鱼的鱼刺各30根,分为大、中、小鱼刺3组,3组鱼刺长度分别为(23.36±0.15)、(28.51±0.07)和(30.89±0.10)mm,直径分别为(4.4.9±0.31)、(1.78±0.09)和(0.49±0.07)mm.将鱼刺按照与食管长轴平行、垂直、斜行方式插入食管模型中,MSCT检查采用轴面扫描结合三维重组技术,观察MSCT和X线平片(CR和DR)对鱼刺的显示情况.临床组:回顾性分析20例经内镜或临床手术证实的食管鱼刺异物患者的资料,所有患者均行MSCT平扫,其中11例行X线平片(CR和DR)检查,15例行食管吞钡棉絮检查,17例行内镜检查,观察几种检查方法对鱼刺的显示情况.对不同方法对鱼刺显示情况的比较采用配对卡方检验.结果 实验组:MSCT检出鱼刺90根(100%),X线平片(CR和DR)检出鱼刺60根(66.7%),MSCT对鱼刺的检出率高于X线平片(CR和DR)(X2=28.03,P<0.01).临床组:20例中,MSCT检出鱼刺20例,且清楚显示鱼刺的位置、大小及其与食管壁和邻近组织的关系;X线平片检出鱼刺2例,食管吞钡棉絮检出鱼刺9例,内镜检出鱼刺14例.MSCT对食管鱼刺异物检出率高于X线平片(cR和DR)检查(X2=7.11,P<0.05)及食管吞钡棉絮检查(X2=4.17,P<01 05),与内镜检查差异无统计学意义(X2=1.33,P>0.05).结论 MSCT轴面扫描结合三维重组技术对食管鱼刺异物及其周围并发症的检出率高,可作为食管鱼刺异物的首选检查方法.  相似文献   
106.
This article is one of a two part series examining the people and environment associated with patient handling. The approach used was that of an occupational injury investigation of a job class, which incorporates defining in the task, environment, tools, and worker health status. Hence, the objective of this portion of the research was to develop a method and use it to compare the physical and mental health of Alabama nurses with known normative populations to determine a baseline of overall health. For this purpose, the validated SF-36© survey was used to collect data on Alabama nurses who had been registered in the state for at least one year. The potential participant pool included 1000 nurses randomly selected from more than 49,000 registered. Physical mailers with a pre-paid return envelope and a follow-up reminder post-card were used. A return rate of 10% was expected based on nursing literature. One hundred and one surveys were returned with 87 being complete. Results confirmed that nursing in the US is a female dominated profession with the survey matching both the Alabama and US national average of 92%. Comparisons of the sample data to general populations yielded significant differences in 3 of the 8 outcome measures: social functioning; physical functioning; bodily pain. In each of these measures, Alabama nurses had a reduced health status compared to at least one comparative population. Additionally, data related to body mass index (BMI) for Alabama nurses were stratified by gender and age. Results indicated 28% had a “healthy” BMI with 37% and 35% of the nurses being “overweight” or “obese”, respectively. Consequently, results suggest Alabama nurses have a reduced health status compared to normative populations and show similar but not identical BMI trends to the general populations for the state of Alabama and the US, which warrants concerns about potential declines in health status among caregivers.

Significance to healthcare

Nurses constitute the largest proportion of the healthcare industry’s workforce. Understanding the perceptions of health status of this employee group is essential to gain further information about possible influences of health on nurses’ ability to continue to perform their jobs.  相似文献   
107.
Activating gene mutations, gene amplifications and overexpressed proteins may be useful as targets for novel therapies. Alterations at chromosome locus 4q12 are associated with gliomas and the region harbors the receptor tyrosine kinase gene KIT, which is frequently amplified in gliomas, and also overexpressed in a subset of gliomas. KIT and its ligand stem cell factor are widely expressed in embryonic and adult mouse brain, and they play a role in many signal transduction pathways involved in cellular proliferation, differentiation and cancer cell metastasis. However, the function of KIT in gliomagenesis or disease progression remains unresolved as well as its role in neural and brain tumor development. In this study, we utilized lentivirus-mediated gene transfer to deliver the KIT gene into mouse astrocytes. The growth properties of KIT overexpressing cells were analyzed using several in vitro functional assays. The effect of receptor tyrosine kinase inhibitor imatinib on astrocyte growth was also investigated. Our results indicate that overexpression of KIT in mouse astrocytes promotes cell proliferation, and the increased proliferation is partly inhibited by imatinib treatment. Furthermore, KIT overexpression induces phenotypic changes in the cells suggesting that KIT may play a role in astrocyte growth regulation.  相似文献   
108.
Congenital left atrial appendage ostial stenosis is a very rare congenital cardiac condition. We present the case of an extremely premature infant with congenital left atrial appendage ostial stenosis diagnosed by transthoracic echocardiographic imaging.  相似文献   
109.
Introduction: Changes in muscle architecture induced by eccentric knee extensor training remain unclear, as well the adaptive responses of synergistic knee extensor muscles with different geometrical designs. Methods: Ultrasonography images were taken from rectus femoris (RF) and vastus lateralis (VL) of 20 male volunteers before and after a non‐training control period of 4 weeks, and additional evaluations were performed after 4, 8, and 12 weeks of isokinetic eccentric training. Results: RF and VL had significant changes in muscle architecture within the first 4 training weeks, and the adaptive response throughout the intervention was similar. Muscle thickness increased by around 7–10%, fascicle length increased 17–19%, and pennation angle was unchanged. Conclusions: Increased muscle thickness due to eccentric training was related to increased fascicle length and not to pennation angle changes. Although RF and VL have a different fascicular geometry, they had similar morphological adaptations to eccentric training. Muscle Nerve 48 : 498–506, 2013  相似文献   
110.
Results of nonlinear finite element analysis support the Schachar theory of accommodation and demonstrate that the long-held Helmholtz theory of accommodation is impossible.  相似文献   
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