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61.
T Sand LJ Stovner G Myhr O Sjaastad 《Cephalalgia : an international journal of headache》1990,10(1):9-16
Various possible risk factors for postlumbar puncture (and postiohexol-myelographic) headache and associated side effects were analysed. Headache and nausea occurred significantly more often in patients without clinical findings than in those with findings. We found significantly different incidences of severe headache and nausea between diagnostic subgroups after a lumbar puncture. The greatest headache incidence was found in patients without a definite neurological diagnosis, while nausea occurred most frequently in patients with various painful disorders. Following iohexol myelography, nausea occurred most often in patients who had a history of previous mental symptoms and in patients with a history of previous headache disorders. Mental symptoms were more frequently reported in patients who also had experienced mental symptoms previously. The relationship between side effects and negative clinical findings was stronger than the relationship between side effects and previous mental symptoms. 相似文献
62.
目的:分析普通男大学生髋、膝、踝、肩、肘各关节相对峰力矩与蹲跳高度的相关性。方法:实验于2004-11/2005-01在河北省体科所完成。①实验对象:随机抽取河北省某大学普通男生30名,年龄(21.8±0.8)岁,身高(170.67±5.48)cm,体质量(65.70±7.99)kg,测试前均从未进行过专门的肌肉力量训练,优势上、下肢均为右侧。②实验方法:从站立开始加摆臂的反向蹲跳,要求受试者上体尽可能保持前后方向稳定,从站立位开始下蹲时上肢向下加速摆臂,并迅速向上蹬伸起跳。从站立开始不加摆臂的反向蹲跳,是排除上肢对蹲跳高度的影响。从半蹲开始加摆臂的无反向蹲跳,要求半蹲的角度控制在105°,静止状态下半蹲预备后,直接进入向上的蹬伸起跳过程,不能出现在起动瞬间身体重心先小幅下移再向上的情况。每种动作做3次,每次间隔10min。③实验评估:通过爱捷图像解析系统得出蹲跳高度,取成绩最好的一次采用Biodex Ⅱ型等速测力及康复系统检测受试者各关节肌力相对峰力矩。利用多因素优势分析法得出在慢速[60(°、快速[240(°)/s])/s]状态下,髋、膝、踝、肩、肘关节相对峰力矩与蹲跳高度的相关性。结果:①从站立开始加摆臂的反向蹲跳高度与各关节相对峰力矩的关系:在慢速状态时与髋关节伸肌相对峰力矩、踝关节背屈肌相对峰力矩、膝关节伸肌相对峰力矩呈明显相关(r=0.808,0.692,0.656),在快速状态时与肘关节屈肌相对峰力矩呈明显相关(r=0.770)。②从站立开始不加摆臂的反向蹲跳高度与各关节相对峰力矩的关系:在慢速状态时与踝关节背屈肌相对峰力矩呈明显相关(=0.747),在快速状态时与膝关节屈肌相对峰力矩呈明显相关(r=0.796)。③从半蹲开始加摆臂的无反向蹲跳高r度与各关节相对峰力矩的关系:从半蹲开始加摆臂的无反向蹲跳高度,在慢速状态时与髋关节伸肌相对峰力矩、踝关节背屈肌相对峰力矩、膝关节伸肌相对峰力矩呈明显相关(r=0.774,0.762,0.712),在快速状态时与肘关节屈肌相对峰力矩呈明显相关(r=0.843)。结论:①加摆臂的反向与无反向蹲跳,髋关节伸肌相对峰力矩、肘关节屈肌相对峰力矩分别是慢速、快速状态下影响其高度的首要因素。②不加摆臂的反向蹲跳,踝关节背屈肌相对峰力矩、髋关节伸肌相对峰力矩分别是慢速、快速状态下影响其高度的首要因素。③提示发展上肢肌肉力量对蹲跳高度的提高大有益处。 相似文献
63.
64.
JJ Korelitz ; AE Williams ; MP Busch ; TF Zuck ; HE Ownby ; LJ Matijas ; DJ Wright 《Transfusion》1994,34(10):870-876
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect. 相似文献
65.
Background: The increased use of white (WBC)-reduced blood components has prompted many institutions to develop quality assurance programs directed to such component preparation processes. For consistent preparation of WBC-reduced blood components that meet clinical needs as well as national standards, a program of process validation and control should be instituted. This involves controlling key factors that affect WBC reduction as well as periodic monitoring of the residual cellular content of components. Practical guidelines for the implementation of such a program are provided. Study Design and Methods: A program involving three phases of monitoring was developed by individuals belonging to an international working party of the International Society of Blood Transfusion. Results: The first phase, process validation, evaluates a minimum of 20 consecutive units (a minimum of 60 units when nonparametric measurements are used) to document the successful local implementation of a new or substantially modified process. Ongoing process control employing Levey-Jennings type control charts is used to demonstrate that the process remains stable over time. Process capability assessment and conformance with standards are evaluated once residual WBCs are counted in a sufficient number of units. This enables a facility to claim with a specified degree of confidence that a stated proportion of WBC-reduced units will meet national standards. Two approaches to determine the number of units that should be selected for counting are presented. The first approach considers units as either acceptable or not acceptable and assumes that the distribution of failed (or nonconforming) units approximates the Poisson distribution. The second approach takes into consideration the observed WBC content of the tested units, with the assumption that the residual WBC content in WBC-reduced components follows a lognormal distribution. A method to assess the lognormal distribution of residual WBCs is presented. Specific tables based on each of these approaches are provided to guide the reader in the design of a program that will verify conformance with any national standard at specific confidence levels. The approach can be generalized to other process control applications. Conclusion: Guidelines are presented for process validation, process control, and assessment of conformance in the production of WBC-reduced blood components. Policy makers retain the responsibility to establish, on the basis of the expected use of WBC- reduced components, requirements for the frequency of testing and for the proportion of prepared units that are expected with a stated degree of confidence to meet the standards. Facilities preparing WBC-reduced components can monitor key factors that influence the preparation of WBC-reduced blood, can periodically assess their conformance with the standards, and can intervene to correct adverse changes in the process. This approach can be used to ensure the consistent quality of WBC- reduced blood components. 相似文献
66.
LJ Dumont 《Transfusion》1991,31(5):428-432
Attention to the accurate and precise measurement of the white cell (WBC) content of transfused products has risen in response to awareness of the potential benefits of WBC-depleted components and the development of technical capabilities to produce these components. The techniques thus far reported have focused on the reliability of detecting a WBC, provided it is present in the test system. The likelihood of selecting a WBC from the product of interest for counting in the analytical system--that is, the sampling error--must also be considered. The occurrence of a WBC in a WBC-depleted component is a rare event and may be modeled with the binomial or the Poisson distribution. Several assay techniques were analyzed by using these distribution models to determine the confidence intervals of the WBC content. The 95-percent confidence intervals spanned more than 2 logs10 for some methods at 3 x 10(5) WBCs per product. It is concluded that the reporting of WBC content for research provides not only the estimate of the mean but also a confidence interval for this estimate. Quality control procedures should be designed to verify that the WBC content is less than the targeted amount and should provide an associated statement of confidence. 相似文献
67.
The effectiveness of the confidential unit exclusion (CUE) procedure recommended by the Food and Drug Administration has been questioned by the blood banking community. The purpose of this study was to determine whether donors were informing the blood center correctly regarding the disposition (transfuse or do not transfuse) of their donated blood. A letter explaining the confidential study and requesting permission to send the participant a questionnaire noting his or her self-exclusion choice was mailed to 230 donors who had chosen transfuse and 276 donors who had chosen do not transfuse. After consent was obtained, participants were sent a second packet and asked to indicate whether they had chosen correctly and, if not, to identify reasons for that incorrect choice. A seven-word terminology quiz made up of words from the CUE form was also enclosed. All participants who had chosen transfuse indicated that this was the correct choice. Approximately 50 percent of those who had chosen do not transfuse indicated that this was an incorrect choice; the most common reason was that "I was not paying attention." The most frequently misunderstood term was "confidential." Donors who chose do not transfuse had a significantly higher rate of error on the terminology quiz (p less than 0.01) than did those who chose transfuse. 相似文献
68.
Li-Jie Li Xiang-Min Zheng Dao-Zhen Jiang Wei Zhang Hong-Liang Shen Cheng-Xiang Shan Sheng Liu Ming Qiu -F Minimally Invasive Surgical Center Changzheng Hospital Second Military Medical University Shanghai China Author contributions: Li LJ Zheng XM Jiang DZ Zhang W Shen HL Liu S Shan CX Qiu M contribute to literature search Qiu M Li LJ Zheng XM wrote the review. 《World journal of gastroenterology : WJG》2010,16(19):2341-2347
The development of laparoscopic surgery has generated the new field of study, laparoscopic anatomy. This article reviews the reported literature on laparoscopic anatomy and explores how it has evolved along with advances in abdominal surgery. In addition, the principal concerns in current laparoscopic anatomy research are discussed, including: (1) types of special adjacent anatomical structures; and (2) special surgical planes and anatomical landmarks. Understanding of systematic laparoscopic anatomy can pr... 相似文献
69.
Oral Diseases (2010) 16 , 136–145 Objective: The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. Design: Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. Methods: The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. Results: Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. Conclusion: Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches. 相似文献
70.
A review of studies of parent-child communication about sexuality and HIV/AIDS in sub-Saharan Africa
Parent-child sexuality communication has been identified as a protective factor for adolescent sexual and reproductive health, including HIV infection. The available literature on this topic in sub-Saharan Africa is increasing; however a systematic review of studies has not been conducted. This article reviews the literature in the area of parental or caregiver and child communication about sexuality and HIV/AIDS in sub-Saharan Africa. A review of peer reviewed literature published between 1980 and April 2011 was conducted. Communication process studies investigating the frequency, content, style, tone of discussions, preferences, as well as associations with and barriers to sexuality communication are reviewed. In addition, studies which examine behavioral associations with parent-child sexuality communication, and intervention studies to improve parent-child sexuality communication are examined. The findings from process studies suggest wide variation in terms of frequency of discussions, with a range of socio-demographic and other factors associated with sexuality communication. Overall, findings demonstrate that discussions tend to be authoritarian and uni-directional, characterized by vague warnings rather than direct, open discussion. Moreover, parents and young people report a number of barriers to open dialogue, including lack of knowledge and skills, as well as cultural norms and taboos. Findings are less clear when it comes to associations between parental communication and adolescent sexual activity and contraception use. However, nascent indications from intervention research suggest positive findings with increases in frequency and comfort of discussions, among other outcomes. Gaps in the research are identified and discussed with implications for future studies. 相似文献