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11.
该研究以山东万杰医学院为例,针对目前招生规模越来越大,生源质量不断下滑,大面积学生逃学、厌学、考试成绩不及格的严峻现实,提出有关教学方法、教学内容和考核方式的教学三项改革,这三项改革举措顺应了当前高校教育(特别是民办高校教育)形势的发展趋势。通过改革实践,已初见成效,进一步验证了只有坚定不移地搞好教学三项改革,才能保证和提高教学质量,从而使广大学生及其家长的利益得到充分保障;也只有大张旗鼓地继续搞好教学三项改革,学校才有生存和可持续发展的空间。  相似文献   
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Current methods using a single PET scan to detect voxel-level transient dopamine release—using F-test (significance) and cluster size thresholding—have limited detection sensitivity for clusters of release small in size and/or having low release levels. Specifically, simulations show that voxels with release near the peripheries of such clusters are often rejected—becoming false negatives and ultimately distorting the F-distribution of rejected voxels. We suggest a Monte Carlo method that incorporates these two observations into a cost function, allowing erroneously rejected voxels to be accepted under specified criteria. In simulations, the proposed method improves detection sensitivity by up to 50% while preserving the cluster size threshold, or up to 180% when optimizing for sensitivity. A further parametric-based voxelwise thresholding is then suggested to better estimate the release dynamics in detected clusters. We apply the Monte Carlo method to a pilot scan from a human gambling study, where additional parametrically unique clusters are detected as compared to the current best methods—results consistent with our simulations.  相似文献   
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Liver transplant allocation policy does not give model for end‐stage liver disease (MELD) exception points for patients with a single hepatocellular carcinoma (HCC) <2 cm in size, but does give points to patients with multiple small nodules. Because standard‐of‐care imaging for HCC struggles to differentiate HCC from other nodules, it is possible that a subset of patients receiving liver transplant for multiple nodules <2 cm in size does not have HCC. We evaluate risk of post‐transplant HCC recurrence and wait‐list dropout for patients with multiple small nodules using competing risks regression based on the Fine and Gray model. We identified 5002 adult HCC patients in the OPTN/UNOS dataset diagnosed and transplanted between January 2006 and September 2010. Compared to patients with >1 tumor <2 cm, risk of developing recurrence was significantly higher in patients with one or more tumors with only one tumor ≥2 cm (SHR 1.63, p = 0.009), as well as in patients with 2–3 tumors ≥2 cm (SHR 1.84, p = 0.02). Dropout risk was not significantly different among size categories. HCC recurrence risk was significantly lower in patients with multiple nodules <2 cm in size than in those with larger tumors, supporting the possibility that some patients received unnecessary transplants. The priority given to these patients must be re‐examined.  相似文献   
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It is often difficult to decouple the relative importance of different factors in regulating MSC differentiation. Genetically modified mice provide model systems whereby some variables can be manipulated while others are kept constant. Fracture repair in thrombospondin‐2 (TSP2)‐null mice is characterized by reduced endochondral ossification and enhanced intramembranous bone formation. The proposed mechanism for this shift in MSC fate is that increased vascular density and hence oxygen availability in TSP2‐null mice regulates differentiation. However, TSP2 is multifunctional and regulates other aspects of the regenerative cascade, such as MSC proliferation. The objective of this study is to use a previously developed computational model of tissue differentiation, in which substrate stiffness and oxygen tension regulate stem cell differentiation, to simulate potential mechanisms which may drive alterations in MSC fate in TSP2‐null mice. Four models (increased cell proliferation, increased numbers of MSCs in the marrow decreased cellular oxygen consumption, and an initially stiffer callus) were not predictive of experimental observations in TSP2‐null mice. In contrast, increasing the rate of angiogenic progression led to a prediction of greater intramembranous ossification, diminished endochondral ossification, and a reduced region of hypoxia in the fracture callus similar to that quantified experimentally by the immunohistochemical detection of pimonidazole adducts that develop with hypoxia. This study therefore provides further support for the hypothesis that oxygen availability during early fracture healing is a key regulator of MSC bipotential differentiation, and furthermore, it highlights the advantages of integrating computational models with genetically modified mouse studies for further elucidating mechanisms regulating stem cell fate. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1585–1596, 2013.  相似文献   
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目的:探讨双切口套法预防开放性胃肠手术后切口感染的临床效果。方法选取2013年3月~2014年8月在本院实施开放性胃肠手术的75例患者作为研究对象,随机分为观察组(38例)和对照组(37例)。观察组在开放性胃肠手术中采用双切口套法,对照组术中不使用任何切口保护套。比较两组的手术时间、术后首次排气时间、首次排便时间、住院时间及切口感染率。结果两组的手术时间比较,差异无统计学意义(P>0.05)。观察组的术后首次排气时间、首次排便时间及住院时间显著短于对照组,差异有统计学意义(P<0.05)。观察组的切口感染率为2.63%,显著低于对照组的16.22%,差异有统计学意义(P<0.05)。结论双切口套法可以明显降低开放性胃肠手术后的切口感染率,提高临床疗效。  相似文献   
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 目的 探讨超声引导下心包穿刺置管引流急慢性心包积液的疗效。方法 回顾分析2009-01至2019-08医院161例行超声引导下心包穿刺置管引流术患者的临床资料,并对其病因、症状、缓解情况进行分析。结果 161例心包积液患者前三位的病因分别为肿瘤、心力衰竭、创伤或手术,经超声引导下心包穿刺置管术治疗后症状缓解率均在70%以上。结论 超声引导下心包穿刺置管引流术治疗心包积液疗效确切,可作为临床治疗心包积液特别是急性心包压塞的首选治疗方式。  相似文献   
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Background: Overdose education and naloxone distribution (OEND) to people at risk of witnessing or experiencing an opioid overdose has traditionally been provided through harm reduction agencies. Expanding OEND to inpatient general medical settings may reach at-risk individuals who do not access harm reduction services and have not been trained. An OEND program targeting inpatients was developed, piloted, and evaluated on 2 general medicine floors at Montefiore Medical Center, a large urban academic medical center in Bronx, New York. Methods: The planning committee consisted of 10 resident physicians and 2 faculty mentors. A consult service model was piloted, whereby the primary inpatient care team paged the consult team (consisting of rotating members from the planning committee) for any newly admitted patient who had used any opioid in the year prior to admission. Consult team members assessed patients for eligibility and provided OEND to eligible patients through a short video training. Upon completion, patients received a take-home naloxone kit. To evaluate the program, a retrospective chart review over the first year (April 2016 to March 2017) of the pilot was conducted. Results: Overall, consults on 80 patients were received. Of these, 74 were eligible and the consult team successfully trained 50 (68%). Current opioid analgesic use of ≥50 morphine milligram equivalents daily was the most common eligibility criterion met (38%). Twenty-four percent of patients were admitted for an opioid-related adverse event, the most common being opioid overdose (9%), then opioid withdrawal (8%), skin complication related to injecting (5%), and opioid intoxication (2%). Twenty-five percent had experienced an overdose, 35% had witnessed an overdose in their lifetime, and 83% had never received OEND previously. Conclusions: Integrating OEND into general inpatient medical care is possible and can reach high-risk patients who have not received OEND previously. Future research should identify the optimal way of implementing this service.  相似文献   
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