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121.
目的调查本地某乡镇一次麻疹疫情的流行强度,描述其三间分布,分析暴发原因及影响因素。方法现场流行病学调查,酶联免疫捕获法检测麻疹IgM抗体,作免疫空白与麻疹发病关联的病例对照研究。结果2006年5月~7月,该乡镇发生30例麻疹局部暴发,其中29例儿童麻疹,1例成人麻疹,5例麻疹IgM抗体阳性。发病地点主要为小学和和幼儿园,罹患率分别为7.94%、7.87%。免疫空白与发病关系研究表明,初种免疫空白OR=7.2,X2=6.84,复种免疫空白OR=11.0,X2=9.48;影响免疫空白形成的社会因素调查,未接受麻疹疫苗初种或复种儿童的父母双亲常年在外务工占82.4%(28/34),有麻疹疫苗接种史儿童的父母常年在外务工占35.3%(12/34),二者有统计学差异(X2=15.54)。结论免疫空白是麻疹暴发形成的重要因素,农村儿童的父母常年在外务工形成隔代抚养教育对计免工作有负面影响。  相似文献   
122.
Inhibiting complement anaphlytoxin C5a during sepsis may prevent sepsis mortality. Although human anti-C5 antibodies exist, their therapeutic use in microbial sepsis has been avoided because of the hypothesis that inhibiting C5b will prevent formation of the bactericidal membrane attack complex (MAC) and worsen clinical outcome. We wished to test the hypothesis that inhibition of C5 would improve outcomes in sepsis. Sepsis was induced in rats by laparotomy and cecal ligation and puncture (CLP) by an IACUC-approved protocol. Sham animals underwent laparotomy without CLP. Following CLP rats were randomized to receive a single IV dose of purified IgG ant-C5 antibody (Ab) or control IgG Ab. Anti-C5 Ab treated rats (n = 20) had significantly lower mortality vs. controls (n = 21), 20% vs. 52% (P = 0.019, log-rank). Analysis of bacterial load by culture of spleen and liver homogenates showed a reduction in colony forming units in anti-C5 Ab treated rats vs. control IgG (P = 0.003 and 0.009, respectively). Anti-C5 treatment reduced lung injury as measured by total MPO content of lung tissue (P = 0.024). Finally, rats genetically deficient in C6 production, unable to form MAC but capable of producing C5a and C5b, were protected from CLP-induced sepsis mortality. Our results show that in anti-C5 antibody therapy prevents CLP sepsis-induced mortality and improves lung injury. Inhibition of the complement MAC does not increase bacterial load or mortality, therefore, the use of anti-C5 therapy may be beneficial rather than detrimental in sepsis.  相似文献   
123.
We have tested the hypothesis that DNA markers in the MAOA gene show allelic association with bipolar affective disorder. Eighty-four unrelated Caucasian patients with DSM III-R bipolar disorder and 84 Caucasian controls were typed for three markers in MAOA: a dinucleotide repeat in intron 2, a VNTR in intron 1, and an Fnu4HI RFLP in exon 8. No evidence for allelic association was observed between any of the markers and bipolar disorder. © 1995 Wiley-Liss, Inc.  相似文献   
124.
The Kv11.1 (also ERG1) K(+) channel underlies cardiac I(Kr), a current that contributes to repolarization in mammalian heart. In mice, I(Kr) current density decreases with development and studies suggest that changes in the structure and/or properties of the heteromultimeric I(Kr)/Kv11.1 channel are responsible. Here, using immunohistochemistry, we report that total Kv11.1 alpha subunit protein is more abundant in neonatal heart and is distributed throughout both adult and neonatal ventricles with greater abundance in epicardia. Immunoblots reveal that the alpha subunit alternative splice variant, Kv11.1a, is more abundant in adult heart while the Kv11.1b variant is more abundant in neonatal heart. Additionally, MinK channel subunit protein is shown to co-assemble with Kv11.1 protein and is more abundant in neonatal heart. In summary, Kv11.1/I(Kr) channel composition varies developmentally and the higher I(Kr) current density in neonatal heart is likely attributable to higher abundance of Kv11.1/I(Kr) channels, more specifically, the Kv11.1b splice variant.  相似文献   
125.
The ophthalmic artery and its branches,measurements and clinical importance   总被引:5,自引:0,他引:5  
Summary Seventy-one Caucasian orbits (36 right, 35 left) were studied by dissection. The diameter of the ophthalmic a. (2 mm from the origin) was 1.54 ± 0.04 mm (male) and 1.31 ± 0.05 mm (female). In individual cases, there were no significant differences in vessel diameter between the right and left sides but, differences in vessel diameter between males and females were more commonly observed in the arteries which leave the orbit (extraorbital group), the individual vessels having a larger diameter in males. The incidence of the ophthalmic a. passing in the orbit medially under the optic n. was 18.6%. The lacrimal a. was observed to arise from the ophthalmic a. in only 82.5% of the cases examined, 15.9% of the cases showed the origin to be at the anastomotic branch of the middle meningealThis article is dedicated to Pr Dr Hoepke on occasion of his 100th birthday  相似文献   
126.
The cricothyroid (CT) and the posterior cricoarytenoid (PCA) muscles in the larynx are activated by the laryngeal motoneurons located within the nucleus ambiguus; these motoneurons receive the laryngeal sensory information from the nucleus tractus solitarii (NTS) during respiration and swallowing. We investigated whether the neurons in the NTS projected directly to the laryngeal motoneurons, and what is the synaptic organization of their nerve terminals on the laryngeal motoneurons using the electron microscope. When wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was injected into the NTS after cholera toxin subunit B-conjugated HRP (CT-HRP) was injected into the CT muscle or the PCA muscle, the anterogradely WGA-HRP-labeled terminals from the NTS were found to directly contact the retrogradely CT-HRP-labeled dendrites and soma of both the CT and the PCA motoneurons. The labeled NTS terminals comprised about 4% of the axosomatic terminals in a section through the CT motoneurons, and about 9% on both the small (PCA-A) and the large (PCA-B) PCA motoneurons. The number of labeled axosomatic terminals containing round vesicles and making asymmetric synaptic contacts (Gray’s type I) was almost equal to that of the labeled terminals containing pleomorphic vesicles and making symmetric synaptic contacts (Gray’s type II) on the CT motoneurons. The labeled axosomatic terminals were mostly Gray’s type II on the PCA-A motoneurons, while the majority of them were Gray’s type I on the PCA-B motoneurons. These results indicate that the laryngeal CT and PCA motoneurons receive a few direct excitatory and inhibitory inputs from the neurons in the NTS. Accepted: 2 June 2000  相似文献   
127.
Summary 819 salivary gland tumors in surgical pathology files over a 25-year period were reviewed. Among 117 adenoid cystic carcinomas, 86 were located in minor salivary glands and were selected for a clinico-pathological analysis. Complementary histoenzymological investigations and electron microscopic study were performed on specimens from 7 and 13 patients respectively.Adenoid cystic carcinoma occured in older patients (mean age of 54 years) than the other salivary neoplasms. The sex ratio was 1/1. The tumor was located more often in the palate and, to a lesser degree in the buccal floor, tongue or gums.Histologically, epithelial nests contained characteristic cyst-like spaces (cylinders) and 3 varieties of such cylinders were described (mucoid, mucohyalin and hyalin). According to the predominant pattern, 3 types of tumors were shown: basaloïd, cribriform and trabecular. A comparison between histological results and clinical behaviour, available in 67 patients, demonstrated positive correlations. The basaloïd form had always a poor prognosis (numerous early recurrences and metastases, frequent lethal evolution). The cribriform type had an intermediate prognosis, better than basaloïd type and less good than trabecular group (100% of patients still alive at 8 years).Histoenzymological studies revealed high level of acid phosphatase, alkaline phosphatase and leucine aminopeptidase activities round cylindromatous cavities. On the other hand, high oxidative enzyme activities were evenly distributed in all cell types.Ultrastructural findings emphasized the immature characters of epithelial tumor cells. These cells contained numerous ribosomes, but few other organelles. Some more differentiated glandular or epidermoid cells were scattered in neoplastic islands. Rare myoepithelial cells lay in periphery of lobules. Cylinder-like spaces were filled with replicated basal lamellae, mucopolysaccharidic granules and fibrillar structures (microfibrils and periodic collagen fibrils).In the light of these results the histogenesis of this neoplasm was discussed. Like the pleomorphic adenoma, adenoid cystic carcinoma was thought to arise from intercalated ducts. Unable to acquire any high degree of differentiation, this blastomatous tumor had a cellular component almost similar to that shown in intermediate stage of salivary gland embryogenesis.The authors wish to thank M.A. Leost and M. Tacnet for their technical assistance  相似文献   
128.
Although Cholesteryl Ester Transfer Protein (CETP) mediates the transfer of cholesteryl esters and triglycerides between lipoprotein particles and thus plays a crucial role in reverse cholesterol transport, the association of variations in the CETP gene with acute myocardial infarction (MI) remains unclear. In this study we examined whether common genetic variation in the CETP gene is related to early‐onset non‐fatal MI risk in a population‐based case‐control study from western Washington State. Genotyping for the CETP ?2708 G/A, ?971 A/G, ?629 A/C, Intron‐I TaqI G/A and exon‐14 A/G (I405V) SNPs was performed in 578 cases with first acute non‐fatal MI and in 666 demographically similar controls, free of clinical cardiovascular disease, identified randomly from the community. In‐person interviews and non‐fasting blood specimens provided data on coronary heart disease risk factors. In men, there was little evidence for an association between single SNPs and MI risk, but in women the age‐ and race‐adjusted OR was found to be significant in 4 out of the 5 CETP single variants. Haplotype analysis revealed two haplotypes associated with MI risk among men. As compared to men homozygous for the most common haplotype D (?2708 G, ?971 G, ?629 C, TaqI G and exon‐14 A), the fully‐adjusted multiplicative model identified haplotype G (?2708 G, ?971 A, ?629 A, TaqI G and exon‐14 G) was associated with a 4.0‐6.0‐fold increased risk of MI for each additional copy; [95%CI 2.4–14.8] and haplotype B (?2708 G, ?971 G, ?629 A, TaqI A and exon‐14 A) showed a significant decreased risk for early onset MI [OR = 0.18; 95%CI 0.04 – 0.75]. An evolutionary‐based haplotype analysis indicated that the two haplotypes associated with the MI risk are most evolutionarily divergent from the other haplotypes. Variation at the CETP gene locus is associated with the risk of early‐onset non‐fatal MI. This association was found to be independent of HDL‐C levels. These data and the sex‐specific findings require confirmation in other populations.  相似文献   
129.
Growing evidence suggests that G‐proteins may be involved in pathogenesis and treatment of affective disorders. Several studies have reported altered levels and/or activities of stimulatory G‐proteins in depression. The aim of this study was to investigate whether a polymorphism in the stimulatory α subunit of G‐proteins (T/C point mutation in exon 5; ATT → ATC at codon 131) is associated with major depression or response to antidepressant treatment. Therefore, we performed a case‐control association study with 212 depressive patients and 137 healthy, unrelated controls. There was no evidence for an association between the investigated polymorphism in the Gαs gene and major depression, as well as to treatment response. The results of our study are in concordance with recently published findings which do not support the hypothesis that the gene for the stimulatory α subunit of G‐proteins is a major susceptibility factor in the pathophysiology of major depression. © 2002 Wiley‐Liss, Inc.  相似文献   
130.
The effects of electrical stimulation of the median raphe nucleus on neuronal discharges in the medial septal area and electrical activity of the hippocampus were examined in urethane-anaesthetized rats. Two cell populations in the medial septal area were differentiated on the basis of their spontaneous discharge pattern, response to median raphe nucleus stimulation and whether or not they were antidromically activated following hippocampal stimulation. Medial septal area cells classified as I-neurones discharge in an irregular pattern which was unrelated to hippocampal activity. In contrast, B-neurones discharge in either rhythmic bursts or in an irregular manner which were related to hippocampal ‘theta’ or ‘desynchronization’, respectively. Single pulse stimulation of the median raphe nucleus inhibited the spontaneous discharge of I-neurones but did not influence the firing of B-neurones or hippocampal activity. Repetitive stimulation of the median raphe nucleus resulted in a prolonged inhibition of I-neurones, a disruption of the bursting discharge of B-neurones, and desynchronization of the hippocampal ‘theta’. The effects of median raphe nucleus stimulation were blocked by pretreatment with parachlorophenylalanine suggesting that a serotonin-containing system originating in the median raphe nucleus may be involved in mediating these responses.  相似文献   
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