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81.
本文报道由于多房棘球绦虫所致的肝泡状棘球蚴病52例:男35例,女17例,年龄14~52岁,多来自牧区。主要体征为上腹部包块,有黄疸者12例,免疫试验均显阳性,辅助检查如B超、同位素扫描、PTC等提示肝内占位性病变,X片显示特殊钙化点。病例均经手术及病理证实。根治手术5例,术后预后好,8~21年随访无复发。姑息性手术7例亦获改善症状等疗效。13例经长达1~16个月的甲苯咪唑化疗无明显副作用,病情改善,包块缩小,药物剂量较大,疗程较长,治疗效果较好。本文就诊断和治疗方面作简要讨论。  相似文献   
82.
《专业证书》制度产生的历史背景自80年代开始,我国进入了社会主义建设蓬勃发展和改革、开放的新时期,现代化建设与管理需要大量的多方面的人才,而且要求人职匹配。据1991年统计,全国有各类卫技人员502万,其中无学历人员约占1/3,县、乡两级分别约占50%及70%,足以说明我国卫技人员学历结构不合理,业务素质较低,与社会主  相似文献   
83.
North America and South America have recently been colonized by the Palearctic species Drosophila subobscura. This double colonization offers a rare opportunity for evolutionary studies. Correlations between chromosomal arrangement frequencies and latitude were calculated for the colonizing populations. Signs of these correlations are highly coincident with those found in the Old World. These results provide experimental support for the adaptive value of the chromosomal-inversion polymorphism; historical and other nonadaptive explanations are thus excluded or relegated to a secondary role.  相似文献   
84.
The ethics of care for the terminally ill in Uruguay spring from deeply rooted attitudes which invest the physician with sole power to determine the course of treatment, even to prescribe painkilling drugs and to hasten death actively or passively, without collaboration from the patient's family. The paternal function attributed to the physician has not been questioned by any systematic reflection on biomedical ethics. However, conscientious physicians are interested in these issues and are well informed about the concerns of their foreign colleagues.  相似文献   
85.
目的 研究长链非编码RNA DNA损伤诱导的非编码RNA (NORAD)在肺癌中的表达及其对肺癌细胞增殖的影响。方法 RNA-seq分析肺癌组织中LncRNA及miRNA的表达改变,根据表达量确定候选LncRNA;q RT-PCR检测分析肺癌组织及肺癌细胞中候选NORAD的表达;免疫荧光检测分析肺癌组织中细胞增殖核抗原Ki-67的表达;通过线性回归分析肺癌组织中NORAD与Ki-67的表达相关性。生物在线软件联合miRNA测序结果,并通过荧光素酶检测分析NORAD与miR-26b-5p、miR-654-5p结合情况。将A549细胞分成空白对照组(Control)、si-NORAD组、miR-26b-5p mimics、miR-654-5p mimics、si-NORAD与miR-26b-5p mimics联合组、si-NORAD与miR-654-5p mimics联合组,利用EdU检测细胞增殖能力、Annexin V-FITC/PI双染检测细胞凋亡、蛋白印迹(Western blot)检测细胞凋亡相关蛋白(Bad、Bcl-2、Cleaved Caspase-3)的表达。结果 NORAD...  相似文献   
86.
Due to its low electrophoretic mobility, few studies have been able to measure gamma aminobutyric acid (GABA) in biological samples by means of capillary zone electrophoresis. Nevertheless, in micellar electrokinetic chromatography (MEKC) by adding a surfactant to the mobile phase separation can be carried out on the basis of the partition coefficient of the molecules rather than their electrophoretic mobility. In the present study microdialysis coupled to MEKC with laser induced fluorescence detection was used to successfully monitor GABA from cerebrospinal fluid and plasma dialysates. Moreover, we monitored changes in extracellular GABA from a human brain. Microdialysis samples were collected from a Parkinson's disease patient undergoing a thallamotomy as part of her treatment. Significant decreases in extracellular GABA were detected during high frequency electrical stimulation and following a thermolesion of the thalamus. These results demonstrate the feasibility of MEKC coupled to laser-induced fluorescence detection in resolving neutral amino acids, specifically GABA, from different human body fluids.  相似文献   
87.
We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1beta (IL-1beta), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-alpha) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-alpha, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1beta, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-alpha levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5).  相似文献   
88.
Hepatitis C virus (HCV) has high genomic variability and at least six different types have been reported. The genotypes distribution is currently unknown among HCV strains circulating in Central America. In order to study the degree of genetic variability of strains isolated in Costa Rica, sequence data obtained from the 5' non coding region from 7 patients from Costa Rica were compared with published sequences from 57 strains of all types. The phylogenetic analysis revealed the existence of type 1 strains of a novel genetic lineage, recently described for some South American countries, and indicates an increasing diversification of HCV.  相似文献   
89.
Unilateral hypoglossal nerve axotomy was used as a model to analyse immunohistochemically the expression of the GluR1, GluR2, GluR3, and GluR4 glutamate receptor subunits of the -amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) subtype and the NR1 subunit of the N-methyl-D-aspartate (NMDA) subtype in the different morphofunctional hypoglossal pools from 1 to 45 days postaxotomy. Following hypoglossal nerve axotomy, the percentage of motoneurons that were GluR1-immunopositive and the labeling intensity for this subunit was increased in some hypoglossal pools. Immunolabeling for the GluR2 subunit was undetectable. These results contrast with the unchanged pattern for these two subunits after sciatic nerve axotomy previously described. Image analysis showed a significant decrease in the intensity of immunohistochemical labeling for the GluR2/3 and GluR4 subunits in motoneurons, although most motoneurons were still immunopositive for these 2 subunits after axotomy. The intensity of immunolabeling for the NR1 subunit was slightly decreased postlesion, whereas the percentage of NR1-immunopositive motoneurons increased. Immunoreactivity returned to basal levels 45 days postlesion. These findings show that in axotomized hypoglossal motoneurons, i) AMPA and NMDA receptor subunits are still expressed, ii) the composition of the ionotropic glutamate receptor subunit pool is subjected to continuous changes during the regeneration process, iii) AMPA receptors, if functional, would have physiological properties different to those in intact motoneurons, and iv) the various AMPA receptor subunits are differentially regulated. The present results also suggest a faster recovery of basal levels of immunoreactivity for caudally localised groups of motoneurons which could reflect a caudo-rostral sequential functional revovery in the hypoglossal nucleus.  相似文献   
90.
The expression of ionotropic glutamate receptor subunits in the motoneuronal pools of the hypoglossal nucleus was studied using specific antibodies against subunits of the -amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA), kainate and N-methyl-D-aspartate (NMDA) subtypes. The highest numbers of intensely immunolabelled motoneurons were found in the dorsal tier and caudoventromedial part of the hypoglossal nucleus with all antibodies except that against the GluR1 AMPA subunit. Labelling for the GluR1 subunit was weak except for caudally located groups of motoneurons which innervate tongue muscles related to respiratory activity. By contrast, most motoneurons were intensely immunostained with antibodies against GluR2/3 and GluR4 subunits of the AMPA subtype. The low staining observed using an antibody specific for the GluR2 subunit (which prevents Ca2+-entry through AMPA channels) strongly suggests that AMPA receptors in hypoglossal motoneurons are Ca2+-permeable. Immunolabelling for the GluR5/6/7 kainate receptor subunits was found in many motoneuronal somata as well as in thin axon-like profiles and puncta that resembled synaptic boutons. Most motoneurons were intensely immunostained for the NMDA receptor subunit NR1. These results show that the hypoglossal nucleus contains five heterogeneous pools of motoneurons which innervate functionally defined groups of tongue muscles. The uneven expression of the different receptor subunits analysed here could reflect diverse phenotypic properties of hypoglossal motoneurons which might be expected to generate different patterns of motor responses under different physiological or pathological conditions.  相似文献   
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