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991.
Cholangiocarcinoma (CC) of the biliary tract occasionally presents a predominant intraductal papillary growth in the bile ducts, called as biliary tract carcinoma (BTC) of papillary growth (PG) and intrahepatic CC (ICC) of intraductal growth (IG) type. Recently, intraductal papillary neoplasm of bile duct (IPNB) has been proposed as a pre-invasive biliary neoplasm. This study was performed to characterize pathologically BTC of PG type and ICC of IG type with respect to IPNB. It was found that 126 of such 154 CCs (81.8%) fulfilled the criteria of IPNB, while the remaining 28 cases showed different histologies, such as tubular adenocarcinoma and carcinosarcoma. These IPNBs occurred in old aged patients with a male predominance, and the left lobe was rather frequently affected in the liver. A majority of these cases were high grade IPNB (43 cases) and invasive IPNB (77 cases), while low grade IPNB was rare (6 cases). Pancreatobiliary type was predominant (48 cases) followed by gastric (30 cases), intestinal (29 cases) and oncocytic (19 cases) types. Mucus hypersecretion was found in 45 cases, and this was frequent in IPNB at the intrahepatic large bile duct and hilar bile ducts but rare at the extrahepatic bile ducts. Interestingly, 36 cases of high grade and invasive IPNBs contained foci of moderately differentiated adenocacinoma within the intraductal papillary tumor. In conclusion, a majority of ICC of IG type and BTC of PG type could be regarded as a IPNB lineage, and clinically detectable IPNBs were already a malignant papillary lesion.  相似文献   
992.
目的 了解东城区学校传染病聚集性疫情的流行特点,探讨学校传染病疫情调查处理的科学方法.方法 通过对北京市东城区2013年9月至2014年1月出现的10起传染病聚集性疫情进行描述性研究,对接报处置以及控制措施的落实情况进行总结分析,总结学校传染病疫情的流行病学特征、病原学特征,分析现行的疫情监测方法和控制措施的优势与不足.结果 在10起疫情中,5起检出腺病毒,平均罹患率为34.1%,罹患率范围在21.3%~53.1%之间;4起检出流感病毒,平均罹患率19.4%,罹患率在8.3%~53.5%之间;1起检出诺如病毒,罹患率16.48%.结论 秋冬季呼吸道病毒和肠道病毒共同威胁着学生健康.在校学生人数多、办学规模大的学校,尤其小学是学校疫情防控的重点.  相似文献   
993.
Abstract

Objective: Autoantibodies directed against the two principal antigens of the human exosome complex, PM75 and PM100, are present in systemic sclerosis (SSc) sera and have been associated with myositis and calcinosis. However, there is a paucity of data on the clinical correlates of these autoantibodies separately and in the absence of other SSc-specific antibodies. The aim of this study was to assess the clinical correlates of monospecific anti-PM75 and anti-PM100 in SSc. Methods: A tri-nation cohort of 1574 SSc subjects was formed, clinical variables were harmonized and sera were tested for anti-PM75 and anti-PM100 antibodies using a line immunoassay. Results: Forty-eight (3.0%) subjects had antibodies against PM75 and 18 (1.1%) against PM100. However, only 16 (1%) had monospecific anti-PM75 antibodies and 11 (0.7%) monospecific anti-PM100 antibodies (i.e. in isolation of each other and other SSc-specific antibodies). Monospecific profiles of each autoantibody included more calcinosis. An increased frequency of myositis was only seen in subjects positive for both anti-PM75 and anti-PM100 antibodies. Lung disease was only associated with anti-PM75 and subjects with anti-PM100 antibodies had better survival compared to other antibody subsets. Conclusion: The prevalence of monospecific anti-PM75 and anti-PM100 antibodies in this large SSc cohort was low. Disease features associated with anti-PM/Scl antibodies may depend on particular and possibly multiple antigen specificities. However, due to the small samples, these results need to be interpreted with caution. International collaborations are key to understanding the clinical correlates of uncommon serological profiles in SSc.  相似文献   
994.
Abstract

BACKGROUND: Simple antiretroviral drug combinations might provide a comparable benefit to standard triple regimens in patients with mild HIV disease, because poor adherence and toxicities often compromise the sustained benefit of the latest triple regimens, especially when protease inhibitors are used. Bad adherence is the main cause of virological failure in HIV-positive children. The activity and safety of a double combination of nucleosides with high genetic barrier for resistance (stavudine plus didanosine) was assessed in children with nonadvanced HIV disease. METHOD: From February 1998 to March 1999, 16 children were enrolled in six Spanish hospitals in a trial in which didanosine (180 mg/m2/day) and stavudine (2 mg/Kg/day) were administered for 48 weeks to asymptomatic naive children with plasma HIV RNA below 50,000 copies/mL and CD4 counts above 15%. Genotypic resistance to nucleoside analogues was examined at baseline and at the end of the study. RESULTS: At baseline, median age was 6.5 years (range, 2-14). The absolute and percentage mean CD4 counts were 864 and 32%, respectively (z score: -0.48 and -1.1). Mean plasma viral load was 4.05 log. No clinical events occurred during the 1-year study period. Minor side effects were recorded in two thirds of children, although none led to drug discontinuation. Lipoatrophy was not recognized in any of the participants. Plasma HIV RNA below 400 copies/mL was reached by 43% and 44% of patients at 24 and 48 weeks, respectively. The z score for absolute and percentage CD4 count increased significantly at 48 weeks (+0.63 and +0.97, respectively) in respect to baseline (p < .05). Resistance mutations linked to didanosine (L74V or M184V) or stavudine (V75T) were not recognized and neither were multinucleoside resistant genotypes (151 complex or 69 inserts). However, four children developed AZT-like mutations T215Y and/or M41L. CONCLUSION: Treatment with a dual combination of didanosine plus stavudine in naive children with nonadvanced HIV disease is safe and provides a satisfactory virological outcome at 1 year. Toxicity and drug resistance seem to occur rarely when this combination is used, which allows good adherence and spares other future treatment options.  相似文献   
995.
996.
Abstract

As a result of population migration, Chagas disease is no longer limited to the North and South American continents. In HIV-infected patients, chronic infection by Try-panosoma cruzi behaves as an opportunistic infection in severely immunosuppressed patients and is responsible for high morbidity and mortality. Unlike other opportunistic infections, information on the natural history, diagnosis, treatment, and prevention of Chagas disease is scarce. Spain has the highest number of cases of Chagas disease outside the North and South American continents, and coinfection with HIV is increasingly prevalent. In this article, the Spanish Society for Tropical Medicine and International Health (Sociedad Española de Medicina Tropical y Salud Interna-cional) reviews the current situation of coinfection with HIV and T. cruzi infection and provides guidelines on the diagnosis, treatment, and prevention in areas where Cha-gas disease is not endemic. It also identifies areas of uncertainty where additional research is necessary.  相似文献   
997.
998.
Mucinous carcinomas represent a distinct morphological subtype which can arise from several organ sites, including the ovary, and their genetic characteristics are largely under‐described. Exome sequencing of 12 primary mucinous ovarian tumours identified RNF43 as the most frequently somatically mutated novel gene, secondary to KRAS and mutated at a frequency equal to that of TP53 and BRAF. Further screening of RNF43 in a larger cohort of ovarian tumours identified additional mutations, with a total frequency of 2/22 (9%) in mucinous ovarian borderline tumours and 6/29 (21%) in mucinous ovarian carcinomas. Seven mutations were predicted to truncate the protein and one missense mutation was predicted to be deleterious by in silico analysis. Six tumours had allelic imbalance at the RNF43 locus, with loss of the wild‐type allele. The mutation spectrum strongly suggests that RNF43 is an important tumour suppressor gene in mucinous ovarian tumours, similar to its reported role in mucinous pancreatic precancerous cysts. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
999.
The objective of this study was to evaluate the switch to once‐daily darunavir/ritonavir 800/100 mg in treatment‐experienced patients with suppressed HIV‐1 replication on a twice‐daily ritonavir‐boosted protease‐inhibitor (bid PI/r) containing regimen, that is in a setting where genotypic resistance test cannot be performed. In this open label, non‐comparative, multicenter study, patients on a bid PI/r‐containing triple combination, with suppressed viral replication, were switched to once‐daily darunavir/r 800/100 mg containing triple combination. The primary endpoint was the proportion of patients with plasma HIV‐RNA < 50 copies/ml 24 weeks after the switch. Intensive darunavir pharmacokinetic evaluation was performed at Week 4 (W4) in 11 patients. Eighty‐five patients were enrolled. All had HIV‐RNA < 50 copies/ml at screening with a pre‐exposure to a median of 2 PI/r (1–5). By intent‐to‐treat analysis (missing = failure), 78/85 patients (92%, 95% CI [83;96]) maintained an HIV‐RNA < 50 copies/ml at W24. Seven patients experienced protocol‐defined treatment failure between baseline and W24: Two had confirmed low‐level viral rebound, one discontinued study treatment for adverse event, three withdrew their consent, and one was lost to follow‐up. By on‐treatment analysis, 78/80 patients (97%, 95% CI [91;99]) maintained an HIV‐RNA < 50 copies/ml at W24. Results were similar at Week 48. The median area under the darunavir plasma concentration–time curve measured in 11 patients was 61,380 ng hr/ml; darunavir median trough concentration 1,340 ng/ml and darunavir half‐life was 12.2 hr. Tolerability of once‐daily darunavir/r 800/100 mg was excellent. Optimally suppressed, treatment‐experienced patients can switch safely from a twice‐daily PI/r regimen to a once‐daily darunavir/r 800/100 mg containing regimen. J. Med. Virol. 85:8–15, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
1000.
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