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101.
正常人肺静脉管径及其血流频谱的研究 总被引:1,自引:0,他引:1
肺静脉血流和肺静脉管径的变化与左房压力及左心室舒张功能密切相关 [1 ,4 ] 。超声心动图可以直接、动态观察肺静脉内径及血流频谱变化 ,但是目前超声尚无健康人肺静脉内径正常值。我们应用彩色超声多普勒技术对正常人及孕周 2 4周以上的妊娠妇女进行肺静脉内径及血流频谱研究 ,以探索正常人肺静脉的显示率、内径正常值、血流频谱特点。观察高动力状态及呼吸对肺静脉管径和血流频谱的影响。1 材料与方法1.1 研究对象 16 9例排除心肺疾患的健康人分组进行研究。其中成年男性组 4 4例、成年女性组 4 6例、儿童组 14例、中期妊娠组 (中妊 … 相似文献
102.
103.
Delineating the sites and progression of in vivo atrophy in multiple system atrophy using fluid-registered MRI. 总被引:1,自引:0,他引:1
Jonathan M Schott Jessica E Simon Nick C Fox Andrew P King M Nadeem Khan Lisa Cipolotti Dominic C Paviour John M Stevens Martin N Rossor 《Movement disorders》2003,18(8):955-958
We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA. 相似文献
104.
C. Pozzilli V. Tomassini F. Marinelli A. Paolillo C. Gasperini S. Bastianello 《European journal of neurology》2003,10(1):95-97
The authors evaluated the gender difference in the magnetic resonance imaging characteristics of the lesions occurring in the brain of 413 multiple sclerosis (MS) patients. Men had fewer contrast-enhancing lesions (P = 0.01), but a higher proportion of lesions evolving into 'black holes' (P = 0.001), when compared with women. Thus, our data indicate that men with MS are prone to develop less inflammatory, but more destructive lesions than women. This study results provides support for a modulation of the MS pathological changes by gender. 相似文献
105.
It is shown that a repetitive pulse sequence consisting of two 90° pulses and gradients in a 1:2 ratio around the second 90° pulse generates interscan shifted stimulated echoes (SSTEs) and intrascan multiple spin echoes (MSEs). Separation of these two types of signals is accomplished using specific gradient crusher schemes. The intensity of the SSTEs is an order of magnitude larger than that of the MSEs and determines the signal contrast if both effects are selected simultaneously. The SSTE sequence generates improved contrast between gray and white matter, even at high field, which is explained in terms of increased inverse T1-weighting for the interscan echo. The MSE image has low signal to noise and no detectable contrast. The effect of interscan diffusion weighting is also discussed. 相似文献
106.
Cohen syndrome: fertility in a female patient 总被引:1,自引:0,他引:1
In this report we describe fertility in an adult female with Cohen syndrome. She gave birth to a son, now 1.5 years old, with discrete facial stigmata and slight psychomotor retardation. 相似文献
107.
目的观察耐药乳腺癌细胞c-myc表达及其反义寡核苷酸对耐药的逆转效应,探讨c-myc在耐药调控中的作用。方法运用流式细胞仪检测乳腺癌耐药细胞MCF-7/Adr和其药敏亲本系MCF-7的c-myc表达水平。MTT法测定阿霉素作用于上述细胞的药物半数抑制浓度(IC50)。结果MCF-7/Adr耐药细胞c-myc的表达率为70.48%,其亲本药敏细胞系MCF-7c-myc表达率仅46.02%,前者显著高于后者(P<0.05)。阿霉素单独作用于MCF-7/Adr,IC50值为(22.00±1.92)μmol/L,但与4μmol/Lc-myc反义寡核苷酸共孵育后,阿霉素的IC50值则显著下降为(9.60±1.04)μmol/L。结论与其亲本药敏细胞相比较,MCF-7/Adr的c-myc表达显著上调,抑制c-myc的过表达可部分逆转MCF-7/Adr的阿霉素抵抗,提示c-myc参与肿瘤耐药的发生。 相似文献
108.
Data from studies of rankings of acceptability and severity of various disabilities were converted to a common metric of percentile equivalent ranks. A total of 1331 data points from 53 studies yielded the following overall percentile equivalent ranks for 24 disabilities: diabetes (most acceptable), ulcer, arthritis, asthma, heart condition, speech problems, crippled, orthopedic disability, physical disability, amputation, emotional disturbance, appearance disability, deafness, learning disability, stroke, cancer, paraplegia, blindness, epilepsy, tuberculosis, cerebral palsy, mental retardation, mental illness, and multiple disabilities (least acceptable). Rankings of the severity of seven disabilities yielded a somewhat different order that correlated 0.55 with the total data. Rankings of a mild disability were, on average, 40 percentile points higher than rankings for the same disability labeled severe or profound. 相似文献
109.
Kirk J. Schneider 《Clinical psychology》2002,9(1):26-27
I contend that although the Luborsky et al. findings on the Dodo bird verdict are noteworthy, the methodology on which they are based is significantly delimited. Amplifying Luborsky et al.'s moderate recognition of that delimitation, I propose a qualitative complement to the extant research. I call this complement "amalgamated" qualitative research and propose that it will deepen, clarify, and contextualize Luborsky et al.'s enigmatic findings. Until this amalgam is implemented, therapy research will be relegated to impressions rather than fine-grained illuminations. 相似文献
110.