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51.
The distributions of calbindin D-28K (CaBP) and parvalbumin (PV) in the rat nucleus olfactorius anterior (NOA) were described using monoclonal antibodies and the avidin-biotin-peroxidase method. The NOA showed a high immunoreactivity for CaBP, with a rostrocaudal increase in the positive neurons and fibres. Pars externa (NOAe) was the only subdivision which showed a low CaBP immunostaining. PV-positive elements were less abundant than those CaBP immunostained. The main difference in the distributions for both proteins was observed in the pars medialis which was practically PV negative. PV- and CaBP-stained neurons showed similar morphologies in the subdivisions where they were present. In NOAe, we observed a characteristic PV- and CaBP-positive neuronal type, with an oriented dendritic pattern. Transition areas were clearly observable in both CaBP- and PV-labelled sections.  相似文献   
52.
北京、广州、上海城市居民营养知识、态度、行为的调查   总被引:27,自引:1,他引:26  
谢斌  吴其乐 《卫生研究》1997,26(5):343-348
对北京、广州和上海三大城市随机抽取的965名年龄在20~50岁的城市居民进行有关营养知识、态度和行为(K-A-P)的调查。结果显示,三地区调查对象的营养知识水平不高。营养知识的得分与其自身受教育程度有相关性(r=0.3011,P<0.01)。年龄在35岁以上的对象,营养知识的得分高于年轻人;三地区调查对象对营养知识的获取,合理的膳食模式,卫生的饮食习惯均持有积极、肯定的态度。食物消费频度调查结果表明,米/面、肉/禽、蔬菜、水果、奶及奶制品的消费量较高。此外,89.5%,78.8%和47.8%的调查对象分别选择报纸、电视、广播作为其主要营养信息来源。本次调查为将来的营养宣教的内容和方法提供依据。  相似文献   
53.
Projection radiographic techniques have been used in a standardized manner for decades for the diagnosis of conditions of the foot and ankle; the indications for them and the pattern of findings useful in the initial diagnosis and monitoring of the course are generally known to clinical radiology staff. Computed tomography has been introduced as an extension of the basic procedures performed for diagnosis in the ankle and the hindfoot. In the case of complex fractures, however, specialist experience is essential. CT is an easily accessible investigative procedure and is meanwhile economical and very powerful. Magnetic resonance imaging supplements the range of investigations in special cases when there are particular problems. Microfractures, findings indicative of inflammation and/or dystrophy and, in particular questions concerning the musculoligamentous support system are the situations in which such investigations are needed. Ultrasound has an additive value vis-à-vis magnetic resonance imaging and is an easily accessible and highly effective examination procedure both for the primary diagnosis and for serial monitoring. Financial constraints in the healthcare sector are increasingly limiting purely medical indications. Regardless of this development, the retention of projection radiography, computer tomography, and magnetic resonance imaging must be demanded for the initial diagnosis in the care of foot and ankle injuries. The earliest possible implementation of all these techniques for the initial diagnosis is the first step towards effective treatment. Cafrefully chosen and, if appropriate, complementary strategies are needed for monitoring of the course and for assessment.  相似文献   
54.
吴新英  马中富 《华夏医学》2003,16(2):288-288,F003
支气管哮喘是常见病和多发病,多种细胞因子参与了支气管哮喘的发病过程。发作期支气管哮喘患者血清可溶性白细胞介素—2受体(SIL—2R)水平明显增高。本文就这方面的进展作一综述。  相似文献   
55.
We present a case of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP‐17) harboring the N279K mutation in the MAPT gene from the family known as pallido‐ponto‐nigral degeneration (PPND). This 49‐year‐old man was followed for 17 years. He presented at age 41 years with left leg stiffness and en‐bloc turning. During the course of his illness he developed a constellation of symptoms including parkinsonism, pyramidal signs, vertical gaze palsy, dysphagia, dystonia, personality and cognitive dysfunction, weight loss and mutism. Gross neuropathological examination showed mild atrophy of the cerebral cortex, hippocampal formation, amygdala, thalamus, subthalamic nucleus and depigmentation of the substantia nigra. Microscopy revealed neuronal loss and gliosis in the same regions. Tau immunohistochemistry showed pretangles, numerous threads, grain‐like structures and oligodendroglial tau‐positive inclusions (“coiled bodies”). In the spinal cord the tau pathology was more abundant in gray than white matter. Pretangles and threads were present in the anterior and, to a lesser extent, in the posterior horns. FTDP‐17 should be suspected in patients with a history of familial parkinsonism combined with behavioral and cognitive changes, onset before age 65 years and an aggressive clinical course.  相似文献   
56.
本系统的107个电极中,103个分布于胸、背部,1个为参考电极,1个为V_3,其余用于肢导。本系统除能绘出2、4、8ms任意间隔的103通道同步的体表等电位图,常规12导联和V_(7 9)心电图,胸、背部位的心电图外,还可记录R峰值等电位图,∑R,Q波等电位图,nQ30、40,极大、极小轨迹图等。  相似文献   
57.
The characteristics of a glial Na+,K+-pump dependent on extracellular K+ within epileptogenic cortex were studied electrophysiologically, biochemically and histochemically in vitro using slices from cobalt-induced epileptogenic cortex of rat. When the extracellular K+ concentration ([K+]o) was varied between 4 and 40 mM, the mean slope of membrane potential plotted against [K+]o was about 57 mV in glia from the normal cortex (tissue A) and about 44 mV in glia from the epileptogenic cortex (tissue B); whereas no significant difference in the resting membrane potential of these tissues was observed. In glia from tissue B, a marked transient hyperpolarization above control level was caused by replacement of elevated [K+]o with the normal medium. Ouabain abolished these phenomena observed in glia from tissue B, but had no effect on the membrane potential during normal [K+]o. Reduction of extracellular Na+, Ca2+ and Cl did not significantly affect the membrane potential of glia from either tissue. In tissue A, the cells marked by intracellular injection of horseradish peroxidase after intracellular recording were protoplasmic astrocytes; in tissue B, fibrous astrocytes with abnormal processes predominated. K+-dependent stimulation of Na+,K+-ATPase activity of the astrocyte-enriched fraction and its membrane preparation from tissue B was much larger than that from tissue A. A certain amount of the reaction product of K+-pNPPase activity was seen on glial plasma membrane within tissue B but not on that from tissue A. The above findings suggest that a glial Na+,K+-pump within actively firing epileptogenic cortex may be modified to increase in its activity.  相似文献   
58.
Partially purified (Na+,K+)-ATPase (E.C. 3.6.1.3.) was investigated in the epileptic cortex of audiogenic DBA/2 mice and in the primary and secondary foci of cats with acute or chronic freeze lesions. No differences in specific activities measured at 3 mM K+ were observed between epileptic and control cortex, except an increase of enzymic activities in the primary focus of acutely lesioned cats. The (Na+,K+)-ATPase catalytic subunits were resolved by SDS-gel electrophoresis and their phosphorylation levels were measured in presence of K+ ions and phenytoin. K+ was more effective in inducing maximal dephosphorylation of (Na+,K+)-ATPase in C57/BL, with identical affinity in the two strains. Phenytoin decreased the net phosphorylation level of (Na+,K+)-ATPase by about 50% in C57/BL mice, but only by 20% in DBA/2 mice. Both K+ and phenytoin dephosphorylating influences were decreased in primary and secondary foci of acutely lesioned cats. Those changes were limited to the alpha(-) subunit. In chronic cats, the dephosphorylating step of the (Na+,K+)-ATPase catalytic subunit recovered a normal affinity to K+, but its sensitivity to phenytoin remained decreased. Those differences in K+ and phenytoin influences on brain (Na+,K+)-ATPases between control and epileptic cortex might be responsible for the ictal transformation and seizure spread. In cats, the alteration of the alpha(-) isoform could mainly affect the glial cells.  相似文献   
59.
Foropenseverewoundandthewoundafterdebridement,mostscholarsthinkthewoundshouldbeclosedindelayedfirst-phase.Meshrelaxingshortincision(MRSI)methodcanclosemoreskindeficiencyandhightensionopenwound,andavoidsubcutaneoushematomaandskinflapdrift.Intheexperiment,theexperimentalmodelonrattensionskinflaphasbeeninvolved,andthecontentofendothelin(ET)inratskinflaptissuehasbeenmeasuredinvariousperiodofwoundhealingaftermeshedrelaxingshortincisionsuturewithimmunohistochemistry,inordertodiscussprobablemechani…  相似文献   
60.
在RPHI试验中,将VitK1或VitK3预先与HBsAg阳性血清作用后,再加抗HBs单克隆抗体诊断红细胞,可见红细胞呈圆点状沉淀,提示HBSAg与抗HBs的结合受到抑制,该抑制作用呈浓度依赖性.RPHI试验后的抗HBs单克隆抗体诊断红细胞,经洗涤后再与HBsAg阳性血清作用,仍出现明显凝集,表明VitK对HBsAg与抗HBs结合的抑制作用不是通过影响抗HBs而产生的。  相似文献   
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