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排序方式: 共有1503条查询结果,搜索用时 12 毫秒
1.
Yukihisa Fukuda Savio L-Y Woo John C Loh Eiichi Tsuda Peter Tang Patrick J McMahon Richard E Debski 《Journal of orthopaedic research》2003,21(6):1107-1112
The loads needed to elicit a positive pivot shift test in a knee with an anterior cruciate ligament (ACL) rupture have not been quantified. The coupled anterior tibial translation (ATT), coupled internal tibial rotation (ITR), and the in situ force in the ACL in response to a valgus torque, an inherent component of the pivot shift test, were measured in 10 human cadaveric knee specimens. Using a robotic/universal force-moment sensor testing system, valgus torques ranging from 0.0 to 10.0 Nm were applied in nine increments on the intact and ACL-deficient knee in flexion ranging from 0 degrees to 90 degrees. At 15 degrees of knee flexion, the coupled ATT and ITR were significantly increased in the ACL-deficient knee when compared to the intact knee. Coupled ATT increased a maximum of 291% (6.7 mm, p<0.05), while coupled ITR increased a maximum of 85% (5.1 degrees, p<0.05). At 30 degrees, the increases in coupled ATT and ITR were significant at valgus loads of 3.3 Nm and greater with a maximum increase in coupled ATT of 137% (6.3 mm, p<0.05) and a maximum increase in coupled ITR of 38% (3.6 degrees, p<0.05). At 45 degrees, coupled ATT increased significantly (maximum of 69%, 4.4 mm, p<0.05), but only at torques > or =6.7 Nm. The in situ force in the ACL was less than 20 N for all flexion angles when a torque between 3.3 and 5.0 Nm was applied. Low valgus torque elicited tibial subluxation in the ACL-deficient knee with low in situ ACL forces, similar to a positive pivot shift test. Thus, application of a valgus torque may be suitable to evaluate ACL-deficient and ACL-reconstructed knees, since subluxation can be achieved with minimal harm to the ACL graft. This work is important in understanding one load component needed for the pivot shift examination; further studies quantifying other load components are essential for better comprehension of the in vivo pivot shift examination. 相似文献
2.
山西省卫Ⅳ项目地区农民因病致贫研究 总被引:4,自引:0,他引:4
目的 研究项目地区农民因病致贫严重程度及预防措施。方法 利用扩展线性支出系统界定贫困标准,观察因病致贫率并研究因病致贫人群特点。结果 农民因病致贫率3.44%,因病致贫人群收入低,健康状况差,馒性病患病率高。2周就诊和年住院率高,年家庭医疗费用支出远高于对照人群。结论 通过住院医疗保险和慢性病防治措施缓解农民因病致贫。 相似文献
3.
Thirty-four social drinkers who had referred themselves to the Regional Brain Damage Unit for assessment of the effects of drinking alcohol were compared with 42 volunteer control subjects of equivalent age but with low alcohol intake, using two 'learning' tests — the Rey Auditory Verbal Learning Test (RAVLT) and the Austin Button Maze. The Maze Test gave no evidence of disorder, but the two groups were significantly different on the RAVLT. No abnormalities in standard cognitive tests were apparent. These results suggest that a deficit in learning ability may be an early feature of the brain dysfunction associated with excessive alcohol consumption. 相似文献
4.
Intending to clarify the true Incidence of Invasive lobular carcinoma of the breast In Japanese women as well as the frequency of unilateral multlcentriclty, 362 cases of clinically defined monocentrlc breast cancer without pre-operative biopsy (previously fine needle aspiration or needle biopsy were routinely carried out for every case) were examined by whole mammary gland serial sectioning. On the basis of pathology and the World Health Organization classification of breast tumors, each case was assigned to one of two main histologlc types: Invasive lobular carcinoma (ILC) or Invasive ductal carcinoma (IDC). Invasive lobular carcinoma was further separated into classic and variant types by employing previously published criteria. Twenty-one cases of ILC (5.8%) were diagnosed, which Is more than In most previous Japanese studies. Unilateral multicentric breast carcinoma was detected In 9.5% of ILC and 16.1% of IDC (the difference was found not significant). Microscopically, ILC tumors were found to be, on average, larger than IDC. Patients with classic type ILC tended to be younger than those with variant type or IDC. Estrogen receptor expression was found more frequently In variant type ILC than in classic type. These results suggest that the incidence of invasive lobular carcinoma of the breast In Japanese women is low and that unilateral multicentricity Is not significantly higher in ILC than in IDC. 相似文献
5.
Hepatitis B control in Europe by universal vaccination programmes: the situation in 2001 总被引:1,自引:0,他引:1
In the nine years since the Global Advisory Group of the Expanded Programme on Immunisation (WHO) set 1997 as the target for integrating hepatitis B vaccination into national immunisation programmes worldwide, 129 countries have included hepatitis B vaccine as part of their routine infant or adolescent immunisation programmes (June 2001). By the end of 2002, 41 out of the 51 countries of the WHO European Region will be implementing universal hepatitis B immunisation. The rewards of effective implementation of the programmes in countries that started 10 years ago are becoming apparent; and their success offers an exemplary model for other countries. Some other countries, however, have difficulties to incorporate hepatitis B vaccine into universal childhood immunisation programmes, because of major economic constrains and the inability to procure a constant vaccine supply. The next decade will be characterised by expanded use of hepatitis B vaccines and the increasing efforts to sustain vaccine programmes and make the vaccine available to those countries and regions that cannot afford it. In Europe, as well as in the rest of the world, work still remains to be done to support and implement interventions that will bring us closer to the WHO goal and to eradicate hepatitis B. 相似文献
6.
Juliana F. W. Cohen Amelie A. Hecht Gabriella M. McLoughlin Lindsey Turner Marlene B. Schwartz 《Nutrients》2021,13(3)
The school environment plays an important role in children’s diets and overall health, and policies for universal free school meals have the potential to contribute to positive child health outcomes. This systematic review evaluates studies examining the association between universal free school meals and students’ school meal participation rates, diets, attendance, academic performance, and Body Mass Index (BMI), as well as school finances. The search was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). A search for studies published in economically developed countries published through December 2020 was performed in PubMed, Education Resources Information Center (ERIC), Thomson Reuters’ Web of Science, and Academic Search Ultimate, followed by examining the references in the resultant literature. A total of 47 studies were identified and the Newcastle-Ottawa Scale (NOS) was applied to assess bias. Nearly all studies examining universal free school meals found positive associations with school meal participation. Most studies examining universal free school meals that included free lunch found positive associations with diet quality, food security, and academic performance; however, the findings of studies examining only universal free breakfast were mixed. Research findings were similarly mixed when examining attendance as an outcome. Concerns about adverse outcomes on student BMI were not supported by the literature; in fact, several studies detected a potentially protective effect of universal free school meals on BMI. Research examining the impact of universal free meals on school finances was limited, but suggest that lower-income school districts in the U.S. may have positive financial outcomes from participation in universal free school meal provisions. Additionally, providing free meals to students may be associated with improved household incomes, particularly among lower-income families with children. Further research is needed to examine the financial implications of universal free meals for both school districts and families. Overall, universal free school meals may have multiple benefits for students and countries should consider universal free school meal provisions with strong nutrition guidelines. (PROSPERO registration: CRD42020221782). 相似文献
7.
Lario Viljoen Virginia A. Bond Lindsey J. Reynolds Constance Mubekapi‐Musadaidzwa Dzunisani Baloyi Rhoda Ndubani Anne Stangl Janet Seeley Triantafyllos Pliakas Peter Bock Sarah Fidler Richard Hayes Helen Ayles James R. Hargreaves Graeme Hoddinott 《Sociology of health & illness》2021,43(1):167-185
Despite continued development of effective HIV treatment, expanded access to care and advances in prevention modalities, HIV‐related stigma persists. We examine how, in the context of a universal HIV‐testing and treatment trial in South Africa and Zambia, increased availability of HIV services influenced conceptualisations of HIV. Using qualitative data, we explore people’s stigma‐related experiences of living in ‘intervention’ and ‘control’ study communities. We conducted exploratory data analysis from a qualitative cohort of 150 households in 13 study communities, collected between 2016 and 2018. We found that increased availability of HIV‐testing services influenced conceptualisations of HIV as normative (non‐exceptional) and the visibility of people living with HIV (PLHIV) in household and community spaces impacted opportunities for stigma. There was a shift in community narratives towards individual responsibility to take up (assumingly) widely available service – for PLHIV to take care of their own health and to prevent onward transmission. Based on empirical data, we show that, despite a growing acceptance of HIV‐related testing services, anticipated stigma persists through the mechanism of shifting responsibilisation. To mitigate the responsibilisation of PLHIV, heath implementers need to adapt anti‐stigma messaging and especially focus on anticipated stigma. 相似文献
8.
Jarrad A. G. Lum Gillian M. Clark Pamela Barhoun Aron T. Hill Christian Hyde Peter H. Wilson 《Psychophysiology》2023,60(2):e14179
Implicit sequence learning describes the acquisition of serially ordered movements and sequentially structured cognitive information, that occurs without awareness. Theta, alpha and beta cortical oscillations are present during implicit motor sequence learning, but their role in this process is unclear. The current study addressed this gap in the literature. A total of 50 healthy adults aged between 19 and 37 years participated in the study. Implicit motor sequence learning was examined using the Serial Reaction Time task where participants unknowingly repeat a sequence of finger movements in response to a visual stimulus. Sequence learning was examined by comparing reaction times and oscillatory power between sequence trials and a set of control trials comprising random stimulus presentations. Electroencephalography was recorded as participants completed the task. Analyses of the behavioral data revealed participants learnt the sequence. Analyses of oscillatory activity, using permutation testing, revealed sequence learning was associated with a decrease in theta band (4–7 Hz) power recorded over frontal and central electrode sites. Sequence learning effects were not observed in the alpha (7–12 Hz) or beta bands (12–20 Hz). Even though alpha and beta power modulations have long been associated with executing a motor response, it seems theta power is a correlate of sequence learning in the manual domain. Theta power modulations on the serial reaction time task may reflect disengagement of attentional resources, either promoting or occurring as a consequence of implicit motor sequence learning 相似文献
9.
The incidence and clinicopathologic features of unilateral multicentric breast cancer (UMBC) were studied by mammary gland
serial sectioning in 116 cases of clinically defined monocentric breast cancer (MONBC) examined histopathologically at the
Nagano Cancer Detection Center. UMBC was defined as: 1) histopathologically discontinuous tumors each with an intraductal
spread, 2) at least one tumor-free section separating two tumors, and 3) a large primary tumor and other small secondary tumors.
UMBC was detected in 23 of 116 cases (19.8%), all with one secondary tumor. Primary and secondary tumors were located in the
same quadrant in 34.8% and in different ones in 65.2%. The secondary tumors were <5 mm in size in 56.5%. Secondary tumors,
averaging 8.3 mm in size and 25.5 mm in distance from the primary tumor, were almost exclusively noninvasive carcinomas, including
15 (65.4%) noninvasive ductal carcinomas and several special types. The primary and secondary tumors were of the same histologic
type in 3 of 23 cases. UMBC patients averaged 6 years younger than MONBC patients, and the incidence of UMBC tended to be
higher in younger patients (p<0.1). UMBC tended to occur more frequently in quadrant with an average histologie tumor size
significantly smaller than that in MONBC (p<0.01). The histologie types of the primary tumor in UMBC and MONBC were similar,
with common types predominant. Lymph node metastases tended to be slightly more frequent in MONBC.
This high incidence of UMBC calls for careful attention when considering breast conserving therapy. 相似文献
10.
新生儿严重脑室内出血连续腰穿的疗效 总被引:16,自引:0,他引:16
目的为了治疗和预防脑室内出血后脑积水的发生和发展,改善新生儿严重脑室内出血的不良预后。方法1989年以来,对19例在出生后早期经头颅B超诊断为严重脑室内出血(IVH)患儿进行了连续腰穿(LP)治疗。结果有效16例,自动出院1例,失败2例。有效率为84.2%。有效16例初次LP日龄为14.6±5.7d,疗程23.4±12d,平均LP次数9.3±4.7次,平均LP间隔期3.1±1.6d,平均每次放液量6.7±2ml,LP治疗后起效天数为10.1±7.8d。2例在连续LP的同时联用乙酰唑胺治疗亦取得显著疗效。16例平均随访月龄为3.2±1月,体格发育均正常,B超显示12例脑室形态正常,4例脑室呈稳定的轻度增大。失败的2例初次LP迟,初期LP间隔期延长为7-9d,放液量<5ml。同期另有17例严重IVH患儿未予LP治疗。其中4例并发脑积水,5例自动出院,4例早期死亡,余4例其后脑室形态稳定。结论连续LP不失为治疗新生儿严重IVH实用安全有效的方法,LP疗效欠佳时可联用乙酰唑胺治疗。 相似文献