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排序方式: 共有543条查询结果,搜索用时 15 毫秒
51.
PR Hunziker S Smith M Scherrer-Crosbie N Liel-Cohen RA Levine R Nesbitt SA Benton MH Picard 《Circulation》1999,99(5):1-6
Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging. 相似文献
52.
53.
医学生心理健康状况与人格特征的相关分析 总被引:19,自引:4,他引:15
目的 :了解在校医学生的心理健康状况 ,为今后开展心理健教育提供有益的依据。方法 :采用 SCL-90和 EPQ量表对在校 5 88名医学生调查并作相关分析。结果 :医学生出现各类心理问题的比例为 6.80 %~ 3 2 .11% ,以强迫、人际敏感、抑郁和偏执为主。临医和护理专业学生心理问题的侧重点不同。女生在人际敏感、抑郁和恐怖等方面均高于男性。情绪稳定性 N和精神质 P与各因子及总均分呈正相关关系 (P<0 .0 1) ,掩饰度 L 与各因子呈显著负相关 (P<0 .0 1)。多因素回归分析表明 ,情绪稳定性 N和掩饰度 L对心理健康的影响起着重要作用。结论 :搞好学生的心理健康 ,加强健全人格教育是关键 ,同时要根据不同性别和专业区别地对待 相似文献
54.
Gap junction intercellular communication (GJIC) has been measured in cell
lines that represent different stages of chemically induced mouse skin
carcinogenesis. No significant difference in GJIC, as measured by dye
spread, was found in cultures of normal keratinocyte, papilloma or squamous
carcinoma cell lines. There was no correlation, in this system, between the
presence of a mutant Ha-ras gene and down- regulation of communication.
There was, however, a marked decrease in GJIC (80-90%) on progression from
squamous to spindle carcinoma cells. Measurement of GJIC in somatic cell
hybrids shows that the genetic defect responsible for this down-regulation
is recessive and is common to two independently isolated spindle cell
lines. No abnormalities were found in the spindle cells in expression of
connexin 43, a cell component involved in gap junction formation and
permeability. However, expression of E-cadherin, a cell-cell adhesion
molecule implicated in the process of gap junction formation, was missing
in the spindle carcinoma cells. Introduction of an E-cadherin cDNA into the
spindle cells partially restored junctional communication without causing
any noticeable alterations in cell morphology. During the study a non-
tumourigenic keratinocyte line, a sub-clone of a normal keratinocyte line,
was also found to have a low level of GJIC. However, the defect in this
line was shown, by genetic complementation in somatic cell hybrids, to be
different from that in the spindle carcinoma cell lines. Consistent with
these data, analysis by immunofluorescence shows an abnormal distribution
of connexin 43 in these cells.
相似文献
55.
The authors present two cases of percutaneous cecostomy performed with a modified approach previously described for percutaneous gastrostomy and cholecystostomy. T-fastener devices were used to affix the cecum to the anterior abdominal wall; thus, the potential problem of fecal spillage was prevented. In both cases, adequate fecal drainage was provided without complication. 相似文献
56.
57.
YP Panayiotopoulos MD PhD S Padayachee PhD BSC ACE Colchester PhD FRCP PR Taylor MChir FRCS 《International journal of clinical practice》1997,51(6):375-377
In early series the majority of carotid endarterectomies were performed in patients with amaurosis fugax (AFx) or transient ischaemic attacks (TIAs) who were thought to have atheromatous ulcers of the carotid bifurcation or the internal carotid artery (ICA). The degree of stenosis was considered to be of secondary importance. We compared our own data with two British series undertaken in the early and late 80s/early 90s. This reflects the broadening of indications and the change of practice for carotid endarterectomy over the years, on the one hand towards including patients who are at greater risk of perioperative stroke (previous CVAs vs TIAs, crescendo TIAs and stroke in evolution), and on the other towards patients who have had no symptoms attributable to the carotid lesion (asymptomatic cases, combined carotid and cardiac procedures). 相似文献
58.
59.
Autologous and allogeneic bone marrow transplantation for poor prognosis patients with B-cell chronic lymphocytic leukemia 总被引:2,自引:4,他引:2
Rabinowe SN; Soiffer RJ; Gribben JG; Daley H; Freedman AS; Daley J; Pesek K; Neuberg D; Pinkus G; Leavitt PR 《Blood》1993,82(4):1366-1376
Twenty patients with poor prognosis B-cell chronic lymphocytic leukemia (B-CLL) underwent uniform high-dose chemoradiotherapy followed by rescue with multiple monoclonal antibody-purged autologous bone marrow (BM) (12 patients) or T-cell-depleted allogeneic BM from HLA-identical siblings (8 patients) in a pilot study to assess the feasibility of BM transplantation (BMT) in this disease. All had poor prognosis disease by either staging, BM pattern, tumor doubling time criteria, or cytogenetics. All patients achieved remission criteria (defined as < or = 2 adenopathy, absence of splenomegaly, < or = 20% of the intertrabecular space involved on BM biopsy) before BMT. Despite the use of fludarabine, a median of three treatment regimens were required to achieve BMT eligibility. After BMT, all patients achieved complete hematologic engraftment. Toxicities were not significantly different between autologous versus allogeneic BMT. Two toxic deaths were observed. Of 19 evaluable patients, 17 clinical complete clinical remissions (89%) were observed, with 2 patients (1 allogeneic and 1 autologous) exhibiting persistent BM disease. Complete clinical remissions were documented at the phenotypic and molecular level for the majority of patients in whom dual fluorescence for CD5 and CD20 (15 of 15; 100%) and Ig gene rearrangements (11 of 14; 79%) were performed. Although long-term follow-up is needed to assess any potential impact on the disease-free and overall survival of these patients, this study shows the feasibility of using high-dose chemoradiotherapy and BMT in patients with poor prognosis B-CLL. 相似文献
60.
Characterization of CD33 as a new member of the sialoadhesin family of cellular interaction molecules 总被引:14,自引:6,他引:14
CD33 is a member of the Ig superfamily that is restricted to cells of the myelomonocytic lineage but whose functions and binding properties are unknown. It shares sequence similarity with sialoadhesin, CD22, and the myelin-associated glycoprotein, which constitute the Sialoadhesin family of sialic acid-dependent cell adhesion molecules. In the present study, we show that CD33 is a fourth member of this family. As a model for sialic acid-dependent binding, human erythrocytes were derivatized with N-acetylneuraminic acid (NeuAc) in different linkages. A recombinant soluble form of CD33, Fc-CD33, bound red blood cells with a specificity similar to that of sialoadhesin, preferring NeuAc alpha 2,3Gal in N- and O-glycans over NeuAc alpha 2,6Gal in N-glycans. Fc- CD33 also bound selectively to the myeloid cell lines HL-60 and U937. However, CD33 was unable to mediate cell binding after transient expression in COS cells, despite high levels of surface expression. Pretreatment of the CD33-transfected cells with sialidase rendered them capable of mediating sialic acid-dependent binding. These results show that CD33 can function as a sialic acid-dependent cell adhesion molecule and that binding can be modulated by endogenous sialoglycoconjugates when CD33 is expressed in a plasma membrane. 相似文献