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肺癌在中国恶性肿瘤的发病率位居第一,随着低剂量薄层CT在肺癌筛查中的广泛应用,临床发现更多表现为非完全实性结节的肺腺癌,目前众多研究使CT影像学特征和肺腺癌病理的关系得到更进一步的认知,虽然CT能对部分非完全实性结节做出定性和定位诊断,但仍有部分非完全实性结节诊断困难,PET-CT结合了病灶的代谢信息和精确的定位信息,从而提高对肺部结节诊断的敏感性、特异性、准确性,综合多个文献PET-CT在非完全实性结节中的诊断分期价值较CT无明显提升,却在评估预后和制定合适手术方案上可以起到一定的作用,本文就PET-CT在SSN中的应用价值进行阐述。  相似文献   
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The mechanism of the increase in immune response to particular staphylococcal antigen was studied in CBA and BALB/c mice injected by primed bone marrow cells (BMC). It was found that immunostimulatory effect of immune BMC is not mediated by macrophages or T cells, but is associated with staphylococcus-specific B memory cells present in the pool of primed BMC. Splenectomy performed in donor animals prior to immunization did not abolish the induction of stimulating BMC activity. It was concluded that primed B lymphocyte migration from spleen into bone marrow is not obligatory for the induction of staphylococcus-specific immunological memory in the bone marrow.  相似文献   
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The experiments carried out on inbred mice have revealed that the level of the immunological memory to staphylococci depends on the intensity of the antigenic stimulation; high priming dose of antigen proving to be the most effective one. The opposite character of immune responsiveness observed during primary antibody response to particulate staphylococcal antigen in C3H and A/Sn mice increased after the second immunization. It is established that immunological memory to staphylococci may be induced in genetically athymic mice. Many antibody-forming cells are found in the bone marrow of the secondary immunized mice. This phenomenon may be due to the repopulation of the bone marrow tissue by recirculating memory cells.  相似文献   
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In the summer of 1986 the epidemic, whose etiological agents were influenza viruses A (H1N1) and respiratory syncytial virus, was registered among the population of Novoshakhtinsk. In a number of mines 15.3-16.7% of the employees were affected. Influenza viruses A (H1N1) proved to be closely related in their antigenic and biological properties to viruses isolated in the USSR in March-June 1986, as well as to viruses A (H1N1), the etiological agents of the epidemic which developed in the USSR in October-December 1986.  相似文献   
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Objectives Somatoform disorders are common in international primary care settings, but have been little studied in the developing world. The objective of this study was to determine the prevalence of severe undifferentiated somatoform disorder, and its relationship to depression and anxiety, among patients attending walk-in clinics in Trinidad.Methods The study participants, who were all aged 18 years or older and attending walk-in clinics at 16 randomly selected health centres, were surveyed between May and August 2007 using the PRIME-MD questionnaire.Results There were 594 participants (the response rate was 92%), of whom 72.7% were female. Their ages ranged from 18 to 93 years, and 54.5% were over 50 years of age. In total, 37.2% were married and 25.9% were single. Indo-Trinidadians represented 43.1% and Afro-Trinidadians represented 36% of the study sample; 56.5% of the participants reported that their income was less than US$ 400 per month, and 65.7% were unemployed. At walk-in clinics in Trinidad, the estimated prevalence of severe undifferentiated somatoform disorder was 10.3% (95% CI: 7.86–12.74), that of hypochondriasis was 28.5% (95% CI: 24.9–32.1), and that of body dysmorphic disorder was 15.8% (95% CI: 11.9–18.7). Severe undifferentiated somatoform disorder was statistically significantly associated with gender and ethnicity but not with age, level of education, employment status or income. Chi-square testing found significant associations between the presence of severe undifferentiated somatoform disorder and both depression and anxiety (P < 0.05), between hypochondriasis and both anxiety and depression (P < 0.05), and between body dysmorphic disorder and depression (P < 0.05) but not anxiety. Regression analysis suggested that the demographic features that predicted severe undifferentiated somatoform disorder were being female or Indo-Trinidadian.Conclusions Walk-in clinics in Trinidad that serve older patients on a lower income have a high proportion of patients with somatoform disorders as measured by the PRIME-MD scale. These patients exhibit many features of anxiety and depression. These findings have implications for medical training and service delivery.  相似文献   
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As the result of prolonged (17 years) observations of patients with acute respiratory infections hospitalized in basic departments of clinics of the Research Institute of Influenza, coronavirus infection was found to be the cause of respiratory diseases, on the average, in 12% of cases (in some years in 6.8% to 28.6% of cases). The analysis of extensive morbidity rates among different age groups of the population showed that children were affected by coronavirus infection 5-7 times more often than adults. Three year cycles of this infection were established. The periods of coronaviruses activation were accompanied by their detection in patient material by electron-microscopy, a sharp increase of immune response of patients as well as in the number of nosocomial infections and the proportion of the monoinfection of the coronavirus nature. Coronaviruses played the leading role among other viruses in the etiology of hospital respiratory infections. Mucosal antibodies to coronaviruses in the secretions of the nasal cavity proved to be more important than serum antibodies not only in protection from infection, but also in the pattern of clinical manifestations of the disease.  相似文献   
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Background

Influenza viruses are a major cause of morbidity and mortality around the world. More recently, a swine-origin influenza A (H1N1) virus that is spreading via human-to-human transmission has become a serious public concern. Although vaccination is the primary strategy for preventing infections, influenza antiviral drugs play an important role in a comprehensive approach to controlling illness and transmission. In addition, a search for influenza-inhibiting drugs is particularly important in the face of high rate of emergence of influenza strains resistant to several existing influenza antivirals.

Methods

We searched for novel anti-influenza inhibitors using a cell-based neutralization (inhibition of virus-induced cytopathic effect) assay. After screening 20,800 randomly selected compounds from a library from ChemDiv, Inc., we found that BPR1P0034 has sub-micromolar antiviral activity. The compound was resynthesized in five steps by conventional chemical techniques. Lead optimization and a structure-activity analysis were used to improve potency. Time-of-addition assay was performed to target an event in the virus life cycle.

Results

The 50% effective inhibitory concentration (IC50) of BPR1P0034 was 0.42 ± 0.11 μM, when measured with a plaque reduction assay. Viral protein and RNA synthesis of A/WSN/33 (H1N1) was inhibited by BPR1P0034 and the virus-induced cytopathic effects were thus significantly reduced. BPR1P0034 exhibited broad inhibition spectrum for influenza viruses but showed no antiviral effect for enteroviruses and echovirus 9. In a time-of-addition assay, in which the compound was added at different stages along the viral replication cycle (such as at adsorption or after adsorption), its antiviral activity was more efficient in cells treated with the test compound between 0 and 2 h, right after viral infection, implying that an early step of viral replication might be the target of the compound. These results suggest that BPR1P0034 targets the virus during viral uncoating or viral RNA importation into the nucleus.

Conclusions

To the best of our knowledge, BPR1P0034 is the first pyrazole-based anti-influenza compound ever identified and characterized from high throughput screening to show potent (sub-μM) antiviral activity. We conclude that BPR1P0034 has potential antiviral activity, which offers an opportunity for the development of a new anti-influenza virus agent.  相似文献   
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