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141.
The present study investigated whether short-latency stretch reflexes are present during human stumbling reactions. While subjects walked on a treadmill, the forward sway of the foot was unexpectedly obstructed with an obstacle. All subjects showed reflex responses with average latencies of 34–42 ms in both the upper and the lower leg flexors and extensors of the obstructed leg. The amplitudes of these responses depended on the phase in the step cycle and were not strictly related to either the background activity of the corresponding muscles or variations in the perturbation. Hence, mechanisms at a premotoneuronal level might play a role in the active phase-dependent control of these responses. The coactivation of antagonists as well as the lack of obvious kinesiologic consequences following the responses suggest that the short-latency responses may generate joint stiffness. This may be a first line of defense in preparing for the functional reaction, which is generated by longer latency responses, in order to take appropriate action concerning the obstacle. 相似文献
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Association of long‐term glycaemic control on tear break‐up times and dry eye symptoms in Chinese patients with type 2 diabetes 下载免费PDF全文
Andre Ma BA Martin SY Mak Kendrick Co Shih FCOphth Claudia KY Tsui MSc Rachel KY Cheung Sherman H Lee Hubert Leung Joyce NS Leung Jason TH Leung Marco Z Van‐Boswell Michael TL Wong Alex Lap‐Ki Ng FRCS Chi‐Ho Lee FHKCP Vishal Jhanji FRCS Louis Tong FRCS PhD 《Clinical & experimental ophthalmology》2018,46(6):608-615
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输血是挽救创伤患者生命而普遍使用的治疗方法,但其又存在着明显和潜在的危险性。当今,经血液传播传染病和输血反应很少发生,但仍然存在。尽管在临床治疗中试图控制创伤患者休克的发展及损伤的严重度,但其输血后细菌感染、多脏器功能衰竭、死亡的发生率仍较高。 相似文献
147.
Merikallio H Pääkkö P Harju T Soini Y 《International journal of clinical and experimental pathology》2011,4(7):667-673
Aims
We investigated the expression of claudins 18 and 10 in a large set of primary lung carcinomas.Methods and results
Immunohistochemical expression of claudin 18 was seen in 12.7 % and claudin 10 in 12.5 % of lung carcinomas. Their expression significantly associated with each other (p<0.001). The expression of claudin 18 and 10 was most prominent in lung adenocarcinomas which displayed positivity in 21.2% and 23.4 % of cases. Female patients had more often claudin 18 and 10 positive tumors, also separately in adenocarcinomas. Interestingly, claudin 10 (p=0.036) and claudin 18 (p=0.001) were more common in tumours of nonsmokers. In adenocarcinomas claudin 18 predicted a better survival (p=0.032). In Cox multivariate analysis, claudin 18 had an independent prognostic value (p=0.027).Conclusion
The results show that both claudins are most commonly expressed in lung adenocarcinomas and they are more occasionally detected in other histological tumour types. Curiously, female patients and non-smokers express these claudins more commonly suggesting that they may play a part in the carcinogenesis of tobacco unrelated carcinoma. Claudin 18 associated with a better survival in lung adenocarcinoma and had an independent prognostic value and may thus be used in the evaluation of patient prognosis. 相似文献148.
Adalgeir Arason Haukur Gunnarsson Gudrun Johannesdottir Kristjan Jonasson P?r-Ola Bendahl Elizabeth M Gillanders Bjarni A Agnarsson G?ran J?nsson Katri Pylk?s Aki Mustonen Tuomas Heikkinen Kristiina Aittom?ki Carl Blomqvist Beatrice Melin Oskar TH Johannsson P?l M?ller Robert Winqvist Heli Nevanlinna ?ke Borg Rosa B Barkardottir 《Breast cancer research : BCR》2010,12(4):R50
Introduction:
A significant proportion of high-risk breast cancer families are not explained by mutations in known genes. Recent genome-wide searches (GWS) have not revealed any single major locus reminiscent of BRCA1 and BRCA2, indicating that still unidentified genes may explain relatively few families each or interact in a way obscure to linkage analyses. This has drawn attention to possible benefits of studying populations where genetic heterogeneity might be reduced. We thus performed a GWS for linkage on nine Icelandic multiple-case non-BRCA1/2 families of desirable size for mapping highly penetrant loci. To follow up suggestive loci, an additional 13 families from other Nordic countries were genotyped for selected markers.Methods:
GWS was performed using 811 microsatellite markers providing about five centiMorgan (cM) resolution. Multipoint logarithm of odds (LOD) scores were calculated using parametric and nonparametric methods. For selected markers and cases, tumour tissue was compared to normal tissue to look for allelic loss indicative of a tumour suppressor gene.Results:
The three highest signals were located at chromosomes 6q, 2p and 14q. One family contributed suggestive LOD scores (LOD 2.63 to 3.03, dominant model) at all these regions, without consistent evidence of a tumour suppressor gene. Haplotypes in nine affected family members mapped the loci to 2p23.2 to p21, 6q14.2 to q23.2 and 14q21.3 to q24.3. No evidence of a highly penetrant locus was found among the remaining families. The heterogeneity LOD (HLOD) at the 6q, 2p and 14q loci in all families was 3.27, 1.66 and 1.24, respectively. The subset of 13 Nordic families showed supportive HLODs at chromosome 6q (ranging from 0.34 to 1.37 by country subset). The 2p and 14q loci overlap with regions indicated by large families in previous GWS studies of breast cancer.Conclusions:
Chromosomes 2p, 6q and 14q are candidate sites for genes contributing together to high breast cancer risk. A polygenic model is supported, suggesting the joint effect of genes in contributing to breast cancer risk to be rather common in non-BRCA1/2 families. For genetic counselling it would seem important to resolve the mode of genetic interaction. 相似文献149.
150.
AIM: To understand how work climate and related factors influence teamwork and collaboration in a large medical center.METHODS: A survey of 3462 employees was conducted to generate responses to Sexton’s Safety Attitudes Questionnaire (SAQ) to assess perceptions of work environment via a series of five-point, Likert-scaled questions. Path analysis was performed, using teamwork (TW) and collaboration (CO) as endogenous variables. The exogenous variables are effective communication (EC), safety culture (SC), job satisfaction (JS), work pressure (PR), and work climate (WC). The measurement instruments for the variables or summated subscales are presented. Reliability of each sub-scale are calculated. Alpha Cronbach coefficients are relatively strong: TW (0.81), CO (0.76), EC (0.70), SC (0.83), JS (0.91), WP (0.85), and WC (0.78). Confirmatory factor analysis was performed for each of these constructs.RESULTS: Path analysis enables to identify statistically significant predictors of two endogenous variables, teamwork and intra-organizational collaboration. Significant amounts of variance in perceived teamwork (R2 = 0.59) and in collaboration (R2 = 0.75) are accounted for by the predictor variables. In the initial model, safety culture is the most important predictor of perceived teamwork, with a β weight of 0.51, and work climate is the most significant predictor of collaboration, with a β weight of 0.84. After eliminating statistically insignificant causal paths and allowing correlated predictors1, the revised model shows that work climate is the only predictor positively influencing both teamwork (β = 0.26) and collaboration (β = 0.88). A relatively weak positive (β = 0.14) but statistically significant relationship exists between teamwork and collaboration when the effects of other predictors are simultaneously controlled.CONCLUSION: Hospital executives who are interested in improving collaboration should assess the work climate to ensure that employees are operating in a setting conducive to intra-organizational collaboration. 相似文献