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排序方式: 共有7967条查询结果,搜索用时 15 毫秒
1.
Syed M. Gilani Muhammad Khan Andrea Barbieri Manju L. Prasad 《Diagnostic Histopathology》2021,27(6):263-271
Anaplastic thyroid carcinoma (ATC) is an aggressive thyroid malignancy with high mortality rate. This malignancy arises in thyroid follicular cells either denovo or with an associated differentiated thyroid carcinoma component. Clinically, it usually presents as a rapidly enlarging mass, pain and locally compressive symptoms. Histopathologic variability and heterogeneity often pose diagnostic challenges, especially in scant and paucicellular specimens. This article describes the clinical, histopathologic and molecular features of ATC and also addresses the associated diagnostic limitations and challenges. 相似文献
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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
4.
Fabian M. Laage Gaupp Nadia Solomon Ivan Rukundo Azza A. Naif Erick M. Mbuguje Anish Gonchigar Minzhi Xing John D. Prologo Douglas D. Silin Frank J. Minja 《Journal of vascular and interventional radiology : JVIR》2019,30(12):2036-2040
Despite a population of nearly 60 million, there is currently not a single interventional radiologist in Tanzania. Based on an Interventional Radiology (IR) Readiness Assessment, the key obstacles to establishing IR in Tanzania are the lack of training opportunities and limited availability of disposable equipment. An IR training program was designed and initiated, which relies on US-based volunteer teams of IR physicians, nurses, and technologists to locally train radiology residents, nurses, and technologists. Preliminary results support this strategy for addressing the lack of training opportunities and provide a model for introducing IR to other resource-limited settings. 相似文献
5.
目的观察肛窦炎应用针刺配合肠炎散保留灌肠治疗的效果。方法选取2017年10月-2018年10月就诊的72例肛窦炎患者,采用随机数字表法分为观察组(n=36)与对照组(n=36)。对照组给予肠炎散保留灌肠治疗,观察组为针刺配合肠炎散保留灌肠治疗,比较2组症状、疗效及安全性。结果观察组症状(放射痛、指诊症状及镜检症状)少于对照组,总有效率高于对照组,差异有统计学意义(P<0.05);2组安全性相比,差异无统计学意义(P>0.05)。结论针对肛窦炎患者,予以针刺配合肠炎散保留灌肠治疗效果确切,可减少临床症状,加快疾病转归,且治疗安全性较好。 相似文献
6.
Solid-state reactions between sodium hydride and sodium hydroxide are unusual among hydride-hydroxide systems since hydrogen can be stored reversibly. In order to understand the relationship between hydrogen uptake/release properties and phase/structure evolution, the dehydrogenation and hydrogenation behavior of the Na-O-H system has been investigated in detail both ex- and in-situ. Simultaneous thermogravimetric-differential thermal analysis coupled to mass spectrometry (TG-DTA-MS) experiments of NaH-NaOH composites reveal two principal features: Firstly, an H2 desorption event occurring between 240 and 380 °C and secondly an additional endothermic process at around 170 °C with no associated weight change. In-situ high-resolution synchrotron powder X-ray diffraction showed that NaOH appears to form a solid solution with NaH yielding a new cubic complex hydride phase below 200 °C. The Na-H-OH phase persists up to the maximum temperature of the in-situ diffraction experiment shortly before dehydrogenation occurs. The present work suggests that not only is the inter-phase synergic interaction of protic hydrogen (in NaOH) and hydridic hydrogen (in NaH) important in the dehydrogenation mechanism, but that also an intra-phase Hδ+… Hδ– interaction may be a crucial step in the desorption process. 相似文献
7.
Martin Freesmeyer Christian Kühnel Falk Gühne Philipp Seifert 《Journal of ultrasound in medicine》2019,38(12):3311-3319
Fine‐needle aspiration cytology using a novel ultrasound needle guidance system on the basis of standard needle magnetization was consecutively performed in 30 (15 in‐plane and 15 out‐of‐plane) suspicious thyroid nodules. Nondedicated, commercially available needles were used. The technical effectiveness and safety of the system were satisfying; system failures were observed in 2 cases. The needle tip could be (at least occasionally) visualized inside the thyroid nodule in 96%, and the subjective procedure ratings were excellent in 57%. The out‐of‐plane technique was significantly superior in both respects (P = .021 and .027, respectively). Standard needle magnetization ultrasound needle guidance was easy to apply and cost‐effective and has the potential to improve fine‐needle aspiration cytology performance. 相似文献
8.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
9.
目的观察补脾泻肝法治疗腹泻型肠易激综合征的临床疗效。方法100例腹泻型肠易激综合征患者随机分为2组,治疗组60例给予白术芍药散加味,对照组40例给予丙咪嗪合替加色罗治疗。2组均4周为1个疗程,观察疗效,并于3-6个月后观察2组病例复发情况。结果治疗组治愈率为65%,总有效率为85%,6个月内复发率为20%,对照组则分别为32.5%、72.5%、55.56%,2组比较差异均有统计学意义(均P<0.05)。结论补脾泻肝法治疗腹泻型肠易激综合征优于丙咪嗪合替加色罗,疗效确切。 相似文献
10.
仙人掌粉对糖尿病大鼠血糖的影响 总被引:11,自引:0,他引:11
目的 研究仙人掌对糖尿病血糖的影响。方法 采用四氧嘧啶造成大鼠实验性糖尿病模型 ,然后将高、中、低 3种剂量的仙人掌粉加入到基础饲料中进行实验观察。结果 仙人掌粉高 (10g kg·d)、中 (5 .0g kg·d)剂量组均可显著降低糖尿病大鼠空腹血糖 ,并且高剂量组具有显著改善糖尿病大鼠尿量增加的作用。各剂量组对正常大鼠血糖无明显影响。结论 仙人掌粉能有效降低四氧嘧啶所导致的糖尿病大鼠的血糖、尿量 相似文献