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31.
Dry powder inhalers (DPIs) are gaining popularity for the delivery of drugs. A cost effective and efficient delivery device is necessary. Developing new DPIs by modifying an existing device may be the simplest way to improve the performance of the devices. The aim of this research was to produce a new DPIs using computational fluid dynamics (CFD). The new DPIs took advantages of the Cyclohaler® and the Rotahaler®. We chose a combination of the capsule chamber of the Cyclohaler® and the mouthpiece and grid of the Rotahaler®. Computer-aided design models of the devices were created and evaluated using CFD. Prototype models were created and tested with the DPI dispersion experiments. The proposed model 3 device had a high turbulence with a good degree of deagglomeration in the CFD and the experiment data. The %fine particle fraction (FPF) was around 50% at 60?L/min. The mass median aerodynamic diameter was around 2.8–4?μm. The FPF were strongly correlated to the CFD-predicted turbulence and the mechanical impaction parameters. The drug retention in the capsule was only 5–7%. In summary, a simple modification of the Cyclohaler® and Rotahaler® could produce a better performing inhaler using the CFD-assisted design.  相似文献   
32.
BACKGROUNDNasolacrimal duct obstruction leading to epiphora is a common ophthalmologic complaint, and it may derive from amyloidosis in rare cases. There are a few reports about localized amyloidosis, and amyloidosis with involvement and obstruction of the nasolacrimal duct is exceedingly rare. CASE SUMMARYA 54-year-old male presented with a 2-year history of a lump overlying the left lacrimal sac that had grown rapidly for nearly half a year. Physical examination touched a firm lump in the left lacrimal sac. Nasal endoscopy discovered lesions in appearance of sediments with easy bleeding at the entry of the nasolacrimal duct of the left inferior nasal meatus. Computerized tomography scan revealed speckle high density in the left lacrimal sac and the dilated nasolacrimal duct. During an endoscopic exploration and excision, a large number of dacryoliths were exposed. Pathology indicated amorphous pink material and multinucleated giant cell reaction in the fibrous tissue.CONCLUSIONThis case showed amyloidosis in localized form mimicking dacryolith with nasolacrimal duct obstruction. In clinical practice, we should be aware of the possibility of localized amyloidosis in the nasolacrimal excretory system.  相似文献   
33.
随着对肿瘤热疗和肿瘤免疫微环境(TIME)的深入研究,近年来热疗对TIME的作用越来越受到学者们的重视。本文就目前国内外研究进展,对热疗与TIME中几类主要免疫细胞和免疫相关细胞因子的影响及作用机制作一综述。全面而透彻的了解热疗对TIME的调控作用,有助于为肿瘤治疗提供新的思路和方法。  相似文献   
34.
Nilotinib is a specific breakpoint cluster region-Abelson leukemia virus-tyrosine kinase inhibitor that is used as an effective first- or second-line treatment in imatinib-resistant chronic myelogenous leukemia (CML) patients. Hepatotoxicity due to nilotinib is a commonly reported side effect; however, abnormal liver function test (LFT) results have been reported in asymptomatic cases. When alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels are more than five-fold the upper limit of the normal (ULN) or when the serum total bilirubin level is more than three-fold the ULN, dose modification or discontinuation of nilotinib is recommended, resulting in decreased levels of hematological indicators in certain patients with CML. Nilotinib-induced hyperbilirubinemia typically manifests as indirect bilirubinemia without elevated ALT or AST levels. Such abnormal liver functioning is thus not attributed to the presence of a true histologic lesion of the liver. The underlying mechanism may be related to the inhibition of uridine diphosphate glucuronosyltransferase activity. Therefore, nilotinib dose adjustment is not recommended for this type of hyperbilirubinemia, and in the absence of elevated liver enzyme levels or presence of abnormal LFT findings, physicians should consider maintaining nilotinib dose intensity without modifications.  相似文献   
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36.
Infantile hemangiomas (IHs) are the most common benign tumor of infancy, characterized by a natural history of early proliferation in the first months of life to eventual involution during childhood, often with residual fibrofatty tissue. Once involution has been achieved, IHs do not typically recur. We present two cases of exogenous growth hormone therapy resulting in the recurrence of IHs in late childhood, supported by radiological, immunohistochemical, in vitro, and in vivo evidence.  相似文献   
37.
We present the case of a 74-year-old Caucasian female who suffered sudden visual loss after routine phacoemulsification cataract surgery. The patient was subsequently diagnosed with non-arteritic anterior ischaemic optic neuropathy. The case is described in detail, and a concise review of the literature is presented together with the authors’ view on the subject outlined. This is a very rare complication after cataract surgery even in high-risk patients with associated systemic co-morbidities. We suspect that the previous history of obesity, coronary artery disease, and arteriosclerosis contributed to the development of this serious ocular complication. We suggest appropriate measures to reduce the risk of its occurrence.  相似文献   
38.
在当前高中新课标不断改革的背景下,高中数学中增加如导数、积分等属于医用高等数学知识体系的内容,而删减了如反三角函数等医用高等数学中所必须的知识。这势必就会带来医用高等数学课程与高中数学课程在教学内容及教学方法上的不协调,从而出现部分学员高中数学跟不上,大学医用高等数学听不懂的现象。同时,授课教员在教学过程中也常常被这种现状所困扰。本研究根据以上问题,结合实际的调查结果及学员的实际需求,主要从医用高等数学教学内容的设计出发,探讨如何合理设计教学内容与教学方法,以增强学员学习医用高等数学的积极性与主动性,从而进一步提高医用高等数学课堂教学效果。  相似文献   
39.
目的 探究黄石、荆门地区产后妇女母乳喂养自我效能的现状及影响因素,为改善母乳喂养率提供更多理论依据。方法 对2017年12月—2018年3月在湖北省黄石市、荆门市的三所医院住院分娩的产妇进行问卷调查,获得产妇社会人口特征、孕产相关资料、母乳喂养相关情况。采用多元线性回归分析母乳喂养自我效能的影响因素。结果 共1 023名产妇纳入分析,平均年龄(29.0±5.7)岁。已婚占98.3%,初产占54.0%,大专及以上学历占53.9%。研究对象的母乳喂养自我效能平均得分为(45.5±12.3)分。多元线性回归的结果显示:当前不存在乳腺问题(B=2.08,P=0.036)、有母乳喂养经历(B=3.62,P<0.001)、家人提供母乳喂养指导或经验(B=3.20,P=0.001)、丈夫支持母乳喂养(B=5.87,P=0.001)及产后30 min内有医护母乳喂养帮助(B=3.02,P=0.003)的产妇母乳喂养自我效能得分更高。结论 产后妇女的母乳喂养自我效能可能与其健康状况、母乳喂养经历、社会支持及母乳喂养卫生服务有关。应对产后妇女提供广泛的社会支持,加强母乳喂养卫生服务提供,以提高其母乳喂养的自我效能,促进母乳喂养。  相似文献   
40.
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