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151.
We describe a simple method for computer quantification of eye movement (EM) potentials during REM sleep. This method can be applied by investigators using either period-amplitude (PA) or Fast Fourier Transform (FFT) spectral EEG analysis without special hardware or computer programming. It provides good correlations with visual ratings of EM in baseline sleep and after administration of GABAergic hypnotics. We present baseline data for both PA and FFT measures for 16 normal subjects, studied for 5 consecutive nights. Both visually rated and computer-measured EM density (EMD) showed high night-to-night correlations across baseline and drug nights and the computer measures detected the EMD suppression that is produced by GABAergic drugs. Measurement of EM in addition to stage REM provides biologically significant information and application of this simple computer method, which does not require pattern recognition algorithms or special hardware, could provide reliable data that can be compared across laboratories.  相似文献   
152.
在30具(男23.女7)共60例成人尸体上观察与测量了咬肌的动脉与神经来源、咬肌神经的分支以及肌内构筑、咬肌由上颌动脉咬肌支和邻近动脉肌支供血,面动脉与面横动脉的咬肌支为其主要营养动脉.咬肌神经在肌内可分成单干和双干两型,前者居多,两型中其肌内分支间均有吻合.就结果对有关颌面外科应用问题进行了探讨.  相似文献   
153.
154.
A Y Tan  C H Law  Y S Lee 《Pathology》1977,9(1):57-64
The demonstration of hepatitis B antigen in the liver cells in formalin fixed paraffin embedded tissues by Shikata's orcein staining method affords an opportunity to conduct retrospective studies on necrospy materials. Such a study in Singapore showed orcein-positive liver cells in 22 out of 52 (42.3%) and 37 out of 50 (74.0%) cases of cirrhosis of the liver and hepatocellular carcinoma respectively, while only 5 out of 113 (4.4%) 'normal' livers gave positive results. There is a significant difference in the frequency of hepatocellular carcinoma in orcein-positive and orcein-negative cirrhotic livers (28 out of 50, 10 out of 40 respectively). These results suggest a possible aetiological relationship between hepatitis B antigen and hepatocellular carcinoma.  相似文献   
155.
Friedreich's ataxia (FRDA) is the result of mutations in the nuclear-encoded frataxin gene, which is expressed in mitochondria. Several lines of evidence have suggested that frataxin is involved in mitochondrial iron homeostasis. We have transfected the frataxin gene into lymphoblasts of FRDA compound heterozygotes (FRDA-CH) with deficient frataxin expression to produce FRDA-CH-t cells in which message and protein are rescued to near-physiological levels. FRDA-CH cells were more sensitive to oxidative stress by challenge with free iron, hydrogen peroxide and the combination, consistent with a Fenton chemical mechanism of pathophysiology, and this sensitivity was rescued to control levels in FRDA-CH-t cells. Iron challenge caused increased mitochondrial iron levels in FRDA-CH cells, and a decreased mitochondrial membrane potential (MMP), both of which were rescued in FRDA-CH-t cells. The rescue of the low MMP, and high mitochondrial iron concentration by frataxin overexpression suggests that these cellular phenotypes are relevant to the central pathophysiological process in FRDA which is aggravated by exposure to free iron. However, even at physiological iron concentrations, FRDA-CH cells had decreased MMP as well as lower activities of aconitase and ICDH (two enzymes supporting MMP), and twice the level of filtrable mitochondrial iron (but no increase in total mitochondrial iron), and the observed phenotypes were either fully or partially rescued in FRDA-CH-t cells. Free iron is known to be toxic. The observation that frataxin deficiency (either directly or indirectly) causes an increase in filtrable mitochondrial iron provides a new hypothesis for the mechanism of cell death in this disease, and could be a target for therapy.  相似文献   
156.
157.
高师贫困生自我效能感与主观幸福感的特点及关系研究   总被引:2,自引:0,他引:2  
目的分析高师贫困生自我效能感、主观幸福感的特点及关系,为心理健康教育提供依据。方法采用一般自我效能感量表、生活满意度量表、快乐感量表,对218名贫困生和216名非贫困生进行测查。结果①高师贫困生生活满意度、快乐感显著低于非贫困生(t=4.811,P〈0.001;t=2.504,P〈0.05),自我效能感差异不显著。②高师贫困生自我效能感存在性别差异(t=2.117,P〈0.05),男生的自我效能感显著高于女生;生活满意度年级差异显著(F=3.547,P〈0.05),大一学生的生活满意度显著高于大二和大三学生,大二和大三之间的差异不显著。③高师贫困生自我效能感与生活满意度、快乐感呈显著正相关(r=0.349,P〈0.01;r=0.436,P〈0.01)。自我效能感水平越高,幸福感越强。结论高师贫困生主观幸福感相对较低,自我效能感与主观幸福感显著相关,通过提升自我效能感水平可以增强主观幸福感。  相似文献   
158.
Partial androgen insensitivity with sex phenotype variation in two unrelated families was associated with missense mutations in the androgen receptor (AR) gene that disrupted the AR NH(2)-terminal/carboxy terminal interaction. Each mutation caused a single amino acid change within the region of the ligand-binding domain that forms activation function 2 (AF2). In one family, the mutation I737T was in alpha helix 4 and in the other F725L was between helices 3 and 4. Neither mutation altered androgen binding as determined by assays of mutant AR in the patient's cultured genital skin fibroblasts or of recombinant mutant receptors transfected into COS cells. In transient cotransfection assays in CV1 cells, transactivation with the AR mutants at low concentrations of DHT was reduced several fold compared with wild-type AR but increased at higher concentrations. Defects in NH(2)-terminal/carboxy terminal interactions were identified in mammalian two hybrid assays. In similar assays, there was reduced binding of the p160 coactivators TIF2/SRC2 and SRC1 to the mutant AR ligand binding domains (LBD). In the family with AR I737T, sex phenotype varied from severely defective masculinization in the proband to a maternal great uncle whose only manifestation of AIS was severe gynecomastia. He was fertile and passed the mutation to two daughters. The proband of the F725L family was also incompletely masculinized but was raised as a male while his half-sibling by a different father was affected more severely and reared as a female. These studies indicate that the function of an AR AF2 mutant in male development can vary greatly depending on the genetic background.  相似文献   
159.
毫米波辐射对植入前小鼠胚胎及早期胚胎的影响   总被引:3,自引:0,他引:3  
本文报道小鼠受精卵体外及在体受毫米波辐照后一些改变。毫米波源为36.11GHz固态微波连续发生器,波长8mm,功率密度为10mW/cm~2、8mW/cm~2、4mW/cm~2及2mW/cm~2。结果发现2-4mW/cm~2毫米波辐照即可使体外培养之受精卵细胞表面微绒毛减少、脱落,细胞表面形成许多囊泡。透射电镜下可见细胞间隙扩大、胞浆中线粒体膨胀、空化,用FITC-ConA试验可见细胞表面结合荧光减少。酶试验证明辐照后卵胚细胞表面AKP,ATPase,5′-Nase均有降低。在体受精卵细胞经辐射后证明,辐射可使胎儿体重增长减慢,囊胚形成数量下降,植入率降低,而表面酶下降不明显。  相似文献   
160.
We have characterized six chemically induced mutations of the Drosophila dlm-defective (d l m d) gene. The mutants are flightless, but they have an otherwise normal appearance. By electron microscopic examination, a focal atrophy was found in their dorsal longitudinal muscle (DLM) fibers, but no abnormalities in nerve conduction or synaptic transmission were detected by electrophysiological tests. The nerve-evoked muscle spike also seemed to be normal, except that the resting potential of DLM in mutant flies was lower and their membrane excitability was higher than those in the wild type flies. The possible causes of the DLM degeneration in this strain are discussed.  相似文献   
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