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排序方式: 共有404条查询结果,搜索用时 15 毫秒
21.
Speech-controlled generation of radiology reports 总被引:1,自引:0,他引:1
Robbins AH; Horowitz DM; Srinivasan MK; Vincent ME; Shaffer K; Sadowsky NL; Sonnenfeld M 《Radiology》1987,164(2):569-573
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%. 相似文献
22.
Thrombopoietin (Tpo), the ligand for the c-Mpl receptor, is a major regulator of megakaryopoiesis. Treatment of mice with Tpo raises the platelet count fourfold within a few days. Conversely, c-mpl knock-out mice have platelet counts that are 15% that of normal. The subunit structure of the c-Mpl receptor is not fully understood. Some cytokines that stimulate megakaryopoiesis (IL-6, IL-11, leukemia inhibitory factor, and oncostatin M) bind to receptors that use gp130 as a signal transduction subunit. For these reasons, we determined whether gp130 function was required for Tpo-induced signal transduction. Murine marrow cells were cultured in semi-solid media in the presence of Tpo or IL-3, with or without a neutralizing anti-gp130 monoclonal antibody (RX187) or a soluble form of c-Mpl receptor (soluble Mpl) that blocks Tpo bioactivity, and the numbers of colony-forming unit-megakaryocyte (CFU-Meg) colonies were counted on day 5. Murine marrow cells were also cultured in suspension under serum-free conditions for 5 days, and megakaryocyte DNA content was measured by flow cytometry, as an index of nuclear maturation. The addition of RX187 did not block Tpo-induced CFU-Meg colony growth nor CFU-Meg nuclear maturation in suspension culture. However, IL-3-induced CFU-Meg colony growth and megakaryocyte nuclear maturation decreased in the presence of RX187. Soluble Mpl completely ablated Tpo-induced CFU-Meg growth, and partially blocked IL- 3-stimulated CFU-Meg growth. Thus the effects of Tpo on megakaryopoiesis in vitro do not depend on cytokines that signal through gp130. Furthermore, it is unlikely that gp 130 serves as a beta chain for the c-Mpl receptor, as Tpo signalling is unimpaired in the presence of RX187. In contrast, the effects of IL-3 on CFU-Meg growth are mediated in part through Tpo and through gp130-signalling cytokines. 相似文献
23.
Noncardiogenic pulmonary edema is a recognized but uncommon manifestation of type 2 decompression sickness. It typically occurs within 6 hours of a dive. Because the adult respiratory distress syndrome in this setting is believed to be due to microbubbles in the pulmonary vasculature, recompression in a hyperbaric chamber has been recommended as a form of therapy. A patient developed noncardiogenic pulmonary edema following a seawater dive to 75 feet. There was complete radiologic and clinical resolution within 5 hours of hyperbaric therapy. 相似文献
24.
25.
Moore AD; Godwin JD; Muller NL; Naidich DP; Hammar SP; Buschman DL; Takasugi JE; de Carvalho CR 《Radiology》1989,172(1):249-254
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities. 相似文献
26.
Diagnosis of the thoracic outlet syndrome is often difficult, particularly in patients without osseous abnormalities on plain radiographs. The radiographic and computed tomographic (CT) findings were reviewed from 27 patients with thoracic outlet syndrome and 21 normal subjects. The plain radiographs and CT scans were assessed by two independent observers without awareness of the clinical history. Fifteen patients with thoracic outlet syndrome had osseous abnormalities (anomalous cervical ribs; abnormally long, drooping C-7 transverse processes) identifiable on plain radiographs. CT did not provide further diagnostic information in the patients with abnormal radiographs. Eight of 12 patients (66%) with normal plain radiographs had abnormal findings on CT scans, consisting of impingement of the C-7 transverse process on the scalene triangle or anteromedial aspect of the middle scalene muscle. Only two of 21 control patients (9.5%) displayed this CT abnormality (P less than .01). CT may be useful in patients with symptoms suggestive of thoracic outlet syndrome and no osseous abnormalities on plain radiographs. 相似文献
27.
目的:观察人的骨髓间充质干细胞多分化潜能及在糖尿病治疗领域的价值。方法:实验于2005-07/2006-07在青岛大学医学院附属医院内分泌科完成。骨髓来源于非造血系统疾病的16岁儿童胸骨骨髓血(查体以排除造血系统疾病,结果显示为健康体质),经得家属同意。Percoll淋巴细胞分层液分离骨髓间充质干细胞,取第3代细胞,等密度接种于培养瓶中,经CD44抗体、CD45抗体、CD34抗体鉴定。取其第4代细胞,诱导其向脂肪细胞及神经细胞分化,利用碱性成纤维细胞生长因子预处理先获得巢蛋白阳性细胞,分别用两种方法诱导其向胰岛祖细胞的转化:化学物质诱导和共培养法诱导,免疫荧光检测胰岛祖细胞标志-胰十二指肠同源异型盒基因(蛋白的表达,电化学发光法检测其是否表达胰岛素)。胶原酶消化法获取胰腺间充质干细胞,鉴定,用添加碱性成纤维细胞生长因子的无血清低糖DMEM使其增殖。将胰腺间充质干细胞接种于底层已接种骨髓间充质干细胞的6孔板共培养,共培养法诱导骨髓间充质干细胞向胰岛祖细胞的初步转化。结果:成脂诱导及成神经诱导可获得油红O染色阳性细胞以及巢蛋白阳性细胞。化学法向胰岛祖细胞诱导后可检测到PDX-1免疫反应阳性细胞。共培养法诱导也可获得PDX-1免疫反应阳性细胞。新生儿胰腺具有巢蛋白、CK-19阳性的胰腺间充质干细胞,体外高糖诱导可形成胰岛样细胞团。结论:骨髓间充质干细胞在体外具有诱导分化为脂肪细胞、神经元样细胞及胰岛祖细胞的潜能。新生儿胰腺间充质干细胞向胰岛细胞分化过程中所分泌的一些物质对骨髓间充质干细胞向胰岛祖细胞的转化具有促进作用。 相似文献
28.
Waters D Campbell R Capek CM Woll B David AS McGuire PK Brammer MJ MacSweeney M 《NeuroImage》2007,35(3):1287-1302
In fingerspelling, different hand configurations are used to represent the different letters of the alphabet. Signers use this method of representing written language to fill lexical gaps in a signed language. Using fMRI, we compared cortical networks supporting the perception of fingerspelled, signed, written, and pictorial stimuli in deaf native signers of British Sign Language (BSL). In order to examine the effects of linguistic knowledge, hearing participants who knew neither fingerspelling nor a signed language were also tested. All input forms activated a left fronto-temporal network, including portions of left inferior temporal and mid-fusiform gyri, in both groups. To examine the extent to which activation in this region was influenced by orthographic structure, two contrasts of orthographic and non-orthographic stimuli were made: one using static stimuli (text vs. pictures), the other using dynamic stimuli (fingerspelling vs. signed language). Greater activation in left and right inferior temporal and mid-fusiform gyri was found for pictures than text in both deaf and hearing groups. In the fingerspelling vs. signed language contrast, a significant interaction indicated locations within the left and right mid-fusiform gyri. This showed greater activation for fingerspelling than signed language in deaf but not hearing participants. These results are discussed in light of recent proposals that the mid-fusiform gyrus may act as an integration region, mediating between visual input and higher-order stimulus properties. 相似文献
29.
Commentary on the safety of red cells preserved in extended-storage media for neonatal transfusions 总被引:2,自引:0,他引:2
Red cells preserved in extended-storage media are the standard product dispensed by many regional blood centers. When the red cells are intended for neonatal transfusion, concern exists about the safety of the relatively high quantities of additives present in these media. Definitive studies to address these concerns are not available. Therefore, to estimate the effects of additives and to delineate circumstances in which they might be harmful, the quantities transfused in defined clinical settings were calculated, and the following recommendations are offered for transfusing infants less than 4 months of age. First, red cells preserved in extended-storage media should present no substantive risks when used for small-volume (approximately 10 mL/kg) transfusions of premature infants and can be used without additional processing. Second, the risks of the most premature neonatal patients or those with severe renal and/or hepatic insufficiency cannot be defined clearly, and, because data are not available to ensure safety for these infants, removal of the additive medium and resuspension of the red cells in saline or albumin solution immediately before transfusion are recommended. Third, following a similar rationale, it seems prudent to avoid using entire units of red cells preserved in extended-storage media in massive transfusion settings (e.g., exchange transfusion, cardiac surgery, and extracorporeal membrane oxygenation). In these settings, the preservative medium should be removed and the red cells resuspended in the fluid that is most appropriate for the procedure that is planned. It must be emphasized that these recommendations are based on calculations and hypothetical settings, not actual data. Accordingly, they are tentative and should be altered as definitive information becomes available. 相似文献
30.
Transfusion-related acute lung injury caused by an NB2 granulocyte- specific antibody in a patient with thrombotic thrombocytopenic purpura 总被引:3,自引:0,他引:3
HLA and granulocyte-specific antibodies have been implicated in the production of transfusion-related acute lung injury (TRALI). Reported here is a case that suggests that the patient's preexisting condition may play an important role in determining whether TRALI develops upon transfusion of blood products containing anti-white cell (WBC) antibodies. A 29-year-old woman with thrombotic thrombocytopenic purpura (TTP) underwent an uneventful 1.5-volume plasma exchange, which was followed by the transfusion of 2 red cell (RBC) units. At the end of the second RBC transfusion, the patient developed clinical signs and symptoms of noncardiogenic pulmonary edema. Serologic studies demonstrated that the serum from the second RBC donor had no HLA antibodies but did have a granulocyte-specific antibody (anti-NB2) that caused the agglutination of the recipient's granulocytes, which were NB2 positive. Serum from the donor of the first RBC unit and serum from the donors of units used in the exchange had no HLA or granulocyte-specific antibodies that reacted with the recipient's WBCs. Because the donor implicated in this reaction had a history of 21 blood donations, none of which had been associated with a transfusion reaction, we suggest that the patient's preexisting condition played a significant role in this episode of TRALI, owing to the granulocyte-specific antibody. 相似文献