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61.
62.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns. 相似文献
63.
Myocardial tagging in polar coordinates with use of striped tags 总被引:1,自引:0,他引:1
Regional deformation abnormalities in the heart wall provide a good indicator of ischemia. Myocardial tagging with magnetic resonance imaging is a new method of assessing heart wall motion during contraction. Current methods of myocardial tagging either do not provide two-dimensional information or lack a coordinate system well adapted to the morphology of the heart. In this article, the authors describe a new tagging method that provides a true polar coordinate system, with both radial and angular dimensions. This is accomplished with use of a section-selective version of spatially modulated magnetization resulting in striped tags (STAGs). These STAG planes are placed in the myocardium in a star pattern so that they intersect on the long axis of the heart and stripes appear through the width of the heart wall. In the short-axis view during contraction, rotation around the long axis yields angular information such as shear and twist, while separation of the stripes within the myocardium permits measurement of radial thickening. Therefore, this method provides a coordinate system for calculating two-dimensional strain that is adapted to the morphology of the left ventricle. 相似文献
64.
65.
Growth of pancreatic foci and development of pancreatic cancer with a single dose of azaserine in the rat 总被引:1,自引:0,他引:1
Studies were undertaken to characterize the growth of the azaserine-inducedputative preneoplastic lesions in rats and to determine if asingle dose of azaserine would be carcinogenic. Male Lewis ratswere given a single i.p. injection of 30 mg L-azaserine/kg bodyweight at 7 weeks of age. A purified diet was fed throughoutthe study. Rats (1012 per group) were autopsied at 6,9, 12, 15 and 18 months postinitiation, and pancreases werequantitatively evaluated to characterize the growth of acidophilicand basophilic foci and nodules (henceforth called foci), andthe incidence of neoplasms. All azaserine-treated rats had foci,and at all times approximately equal numbers of acidophilicand basophilic foci were present in the pancreas. The numberof basophilic foci increased with time, and while their sizealso increased, this change was small compared with the increasein size of the acidophilic foci. Conversely, all acidophillcfoci appeared to be present by 69 months, and their sizegreatly increased with time. The data suggest that virtuallyall foci persist rather than regress or remodel. At 9 monthsthe incidence of carcinoma in situ was 30% and by 18 monthsthere was a 100% incidence of pancreatic cancers (58% carcinomain situ and 42% carcinoma). 相似文献
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目的:分析辽西地区城市汉族儿童青少年的体型发育规律和特点,为体质人类学补充必要的数据。方法:按整群分层抽样法,抽取2001-07/2003-09辽西地区城市7所中小学7~19岁经学校正常体质检查证明身体健康的汉族学生,按性别分两大组,每大组按年龄分12小组,7~18岁每岁为1个年龄组,18~19岁为1个年龄组,每小组45~86名,共分24组,搜集完整资料1263名(男657名,女606名)。采用Heath-Carter体型法,每项指标测量2次,取平均值,10项指标由专人负责,测试数据按年龄和性别在微机中建立数据库,依次计算出各年龄组的内因子、中因子和外因子,体型图上的X,Y坐标值,身高/体质量1/3,样本中平均体型点到所有体型点空间距离的均数,三维空间中两个体型点间的差异,体脂含量和各类体型分布频数。结果:参加调查1263名,均进入结果分析。①7~17岁儿童青少年身高、体质量随年龄的增加而增长。平均身高、体质量男生大于女生。身高/体质量1/3指数除14,16和17岁外,各年龄组女生>男生,平均值女生>男生。体脂含量11岁以前男生>女生,12岁以后女生>男生。②辽西地区城市汉族男生的平均体型值为3.9-3.5-3.4,属中间型,女生平均体型值为4.3-2.9-3.6,属偏外胚层的内胚层体型。体型频数的变化提示辽西城市汉族男生体型分布较散,女生分布较集中,主要在内胚层体型。③内因子男生在3.18~4.81,女生在3.05~5.33,11岁以前男生>女生,12岁以后女生>男生;中因子男生在3.02~4.23,女生在2.54~3.42,除16岁男女相差不多外,其他年龄组男生>女生,外因子男生在2.64~4.22,女生在2.92~4.14,13岁以前女生>男生,14岁以后男生>女生。因此,男生较女生骨骼粗壮,肌肉发达,随着年龄的增长,女生的皮下脂肪更发达,体态丰满,男生的身体相对瘦高程度增长,身材修长。男女各年龄组间体型比较,7~,8~,9~,10~,11~,12~,13~,14~,15~,16~,17~,18~19岁三维空间中两个体型点间的差异值分别为0.95,0.85,1.10,1.06,1.37,0.43,0.87,1.44,1.42,1.12,1.11,1.33,7~,8~,12~,14~,17~,18~19年龄组男女间体型差异有显著性(t=2.07,4.09,3.12,3.86,3.39,3.99,P<0.05)。④与国内汉族及其他少数民族相比,辽西汉族男生体脂最多,骨骼肌肉不发达,身体相对矮小;辽西地区汉族女生体脂较多,骨骼肌肉不发达,体型修长。结论:辽西地区城市男生较女生骨骼粗壮,肌肉发达,随着年龄的增长,女生的皮下脂肪更发达,体态丰满,男生的身体相对瘦高程度增长,身材修长。与国内汉族及其他少数民族相比,辽西地区城市汉族儿童青少年体脂发育较好,骨骼肌肉欠发达,青春期是形成健壮体型的关键时期,辽西地区城市儿童青少年应注意合理饮食和加强体育锻炼。 相似文献
68.
Agustin Oterino MD Maria Toriello BD Amalia Cayón BD Jesus Castillo MD Rafael Colas MD Ana Alonson‐Arranz Carlos Ruiz‐Alegria MD Estrella Quintela MD Fernando Monton MD Nuria Ruiz‐Lavilla MD Felix Gonzalez MD Julio Pascual MD 《Headache》2008,48(10):1438-1450
Objective.— Female hormone genes have been investigated in migraine in recent years. Research in this field has been controversial, especially in regard to ESR1 gene findings. None of the reports have yet to approach the problem from a multigenic point of view. Methods.— We investigated 5 polymorphisms implicated in female hormone metabolism (FSHR, CYP19A1, ESR1, NRIP1, and ESR2) in a cohort of 730 subjects matched for age and sex. The effect of gene–gene interaction was assessed using the set association approach, and the corresponding haplotypes were studied with PM Plus software. To corroborate initial results, we analyzed the selected markers using a cohort of 134 families in which 168 trios were suitable for transmission‐disequilibrium test (TDT) analysis under the migraine with aura (MA) phenotype. Results.— A total of 356 consecutive migraine patients (198 with MA [76% females] and 158 migraine without aura [MO, 74% females], and 374 matched controls [71% females]) were genotyped. In the 2‐point analyses, the ESR1 and ESR2 polymorphisms showed nominal association under MA/MO phenotype, and this association was higher with the FSHR polymorphism in MA females (P = .004, uncorrected). Using the SUMSTAT program, we observed ESR2‐ESR1‐FSHR significant gene–gene interaction, suggesting association with the MA/MO phenotype (P = .005; P = .003 in females), and with MA alone (P = .021; P = .030 for females). We corroborated that ESR2‐ESR1‐FSHR haplotypes interacted for migraine under a model‐free hypothesis (empirical P = .010 for the whole sample; P = .001 for females), and the association was stronger for the MA phenotype alone (empirical P = 5.0e‐4, under the heterogeneity model; P = .001 for females). These results were corroborated using family‐based association approaches. We observed nominal association for ESR2 and ESR1 (P = .031 and .034, respectively) in the TDT study, and significant association for ESR1 using family‐based association test statistics. Haplotype‐TDT analyses showed further significant gene–gene interaction for ESR1‐ESR2 (global P = .009), ESR2‐FSHR (global P = .011), and nominally significant interaction for ESR2‐ESR1‐FSHR genes (global P = .037). Conclusion.— We found significant association of female hormone metabolism polymorphisms under the perspective of multigene approach. 相似文献
69.
Haker SJ Mulkern RV Roebuck JR Barnes AS Dimaio S Hata N Tempany CM 《Topics in magnetic resonance imaging : TMRI》2005,16(5):355-368
We review our experience using an open 0.5-T magnetic resonance (MR) interventional unit to guide procedures in the prostate. This system allows access to the patient and real-time MR imaging simultaneously and has made it possible to perform prostate biopsy and brachytherapy under MR guidance. We review MR imaging of the prostate and its use in targeted therapy, and describe our use of image processing methods such as image registration to further facilitate precise targeting. We describe current developments with a robot assist system being developed to aid radioactive seed placement. 相似文献
70.
神经生长因子对局灶性脑缺血神经干细胞巢蛋白表达及细胞类型的影响 总被引:1,自引:3,他引:1
目的:实验于2006-02/07在锦州医学院科学实验中心完成。将72只健康SD大鼠按随机数字表法分为假手术组、模型组、神经生长因子治疗组,每组24只。采用Logna等改良法复制大脑中动脉血栓模型,动物清醒2h后进行功能评价,动物神经功能达到2级的纳入实验。假手术组除不进行大脑中动脉线栓外,其余同模型组。神经生长因子治疗组于缺血后立即腹腔注射神经生长因子1000μg/kg,1次/d。于缺血后1,3,7,14d处死动物,运用免疫组化和免疫荧光双标的方法观察神经生长因子对脑缺血后神经干细胞巢蛋白的表达及其细胞类型的影响。结果:72只大鼠均进入结果分析。①神经生长因子治疗组和模型组大脑皮质均可见巢蛋白阳性细胞,细胞呈圆形或椭圆形。与模型组相比,除缺血后1d外,神经生长因子治疗组其他时间点的巢蛋白阳性细胞数均明显高于模型组,两组缺血后各时间点的巢蛋白阳性细胞数均高于假手术组[模型组:(3.47±0.51),(5.13±1.14),(13.95±3.56),(8.97±2.08)个;神经生长因子治疗组:(3.81±0.66),(9.88±2.08),(19.87±3.86),(26.17±2.90)个,假手术组:0,P<0.05,P<0.01]。②模型组和神经生长因子治疗组3d时缺血皮质巢蛋白阳性突起主要与胶质纤维酸性蛋白共存,14d时巢蛋白与神经元特异性烯醇化酶共存明显增多。结论:神经生长因子能增加局灶性脑缺血后巢蛋白的阳性细胞的数目,并促进其分化为神经元和神经胶质细胞。 相似文献