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Summary. Background: A pulmonary embolism (PE) is thought to be associated with atrial fibrillation (AF). Nevertheless, this association is based on weak data. Objectives: To assess whether the presence of AF influences the clinical probability of PE in a cohort of patients with suspected PE and to confirm the association between PE and AF. Patients/methods: We retrospectively analyzed the data from two trials that included 2449 consecutive patients admitted for a clinically suspected PE. An electrocardiography (ECG) was systematically performed and a PE was diagnosed by computer tomography (CT). The prevalence of AF among patients with or without a PE was compared in a multivariate logistic regression model. Results: The prevalence of PE was 22.8% (519/2272) in patients without AF and 18.8% (25/133) in patients with AF (P = 0.28). After adjustment for confounding factors, AF did not significantly modify the probability of PE (odds ratio [OR] 0.68, 95% confidence interval [CI] 0.42–1.11). However, when PE suspicion was based on new‐onset dyspnea, AF significantly decreased the probability of PE (OR 0.47, 95% CI 0.26–0.84). If isolated chest pain without dyspnea was the presenting complaint, AF tended to increase the probability of PE (OR 2.42, 95% CI 0.97–6.07). Conclusions: Overall, the presence of AF does not increase the probability of PE when this diagnosis is suspected. Nevertheless, when PE suspicion is based on new‐onset dyspnea, AF significantly decreases the probability of PE, as AF may mimic its clinical presentation. However, in patients with chest pain alone, AF tends to increase PE probability.  相似文献   
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Bone marrow examination revealed a lipid-laden histiocytosis in seven patients undergoing long-term total parenteral nutrition necessitated by extensive short-bowel surgical resection. Clinical abnormalities occurred during this treatment which required bone marrow examination. These included hepatosplenomegaly and peripheral blood cytopenia; the median time to the detection of these abnormalities was 64 months.   The most striking change within the bone marrow was the presence of many pigment-laden histiocytes which had the typical morphology of sea-blue histiocytes seen in the so-called idiopathic sea-blue histiocyte syndrome. The occurrence of sea-blue histiocytosis in the bone marrow in association with long-term parenteral nutrition for short-bowel syndrome has not, to our knowledge, been reported previously and should now be considered in the differential diagnosis of bone marrow sea-blue histiocytosis.  相似文献   
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Loss-of-function variants in ANKRD11 were identified as the cause of KBG syndrome, an autosomal dominant syndrome with specific dental, neurobehavioural, craniofacial and skeletal anomalies. We present the largest cohort of KBG syndrome cases confirmed by ANKRD11 variants reported so far, consisting of 20 patients from 13 families. Sixteen patients were molecularly diagnosed by Sanger sequencing of ANKRD11, one familial case and three sporadic patients were diagnosed through whole-exome sequencing and one patient was identified through genomewide array analysis. All patients were evaluated by a clinical geneticist. Detailed orofacial phenotyping, including orthodontic evaluation, intra-oral photographs and orthopantomograms, was performed in 10 patients and revealed besides the hallmark feature of macrodontia of central upper incisors, several additional dental anomalies as oligodontia, talon cusps and macrodontia of other teeth. Three-dimensional (3D) stereophotogrammetry was performed in 14 patients and 3D analysis of patients compared with controls showed consistent facial dysmorphisms comprising a bulbous nasal tip, upturned nose with a broad base and a round or triangular face. Many patients exhibited neurobehavioural problems, such as autism spectrum disorder or hyperactivity. One-third of patients presented with (conductive) hearing loss. Congenital heart defects, velopharyngeal insufficiency and hip anomalies were less frequent. On the basis of our observations, we recommend cardiac assessment in children and regular hearing tests in all individuals with a molecular diagnosis of KBG syndrome. As ANKRD11 is a relatively common gene in which sequence variants have been identified in individuals with neurodevelopmental disorders, it seems an important contributor to the aetiology of both sporadic and familial cases.  相似文献   
47.
Using an experimental model of hepatic Echinococcus multilocularis infection in C57BL/6J mice, intraperitoneal administration of 0.8 μg of recombinant IL-12 to mice with an established infection was shown to reduce the parasite burden as soon as two weeks after the end of treatment. At that time, in vitro Echinococcus multilocularis -induced spleen T cell proliferative responses as well as IFN-γ and IL-5 production were higher in IL-12 treated mice than in untreated mice. Administration of 0.8 μg of IL-12 at the time of infection was shown to be without effect on the parasite establishment. However, this treatment greatly inhibited the subsequent metacestode development. Indeed, ten weeks after infection, it induced a complete healing in 37.5% of mice. At that time, the development of metastases was inhibited in 68.75% of IL-12-treated mice. This reduction of parasite burden was mainly associated with a strong proliferation of spleen cells to E. multilocularis antigen and with a high IFN-γ production. Altogether, our results show that IL-12 is of crucial importance in inhibiting the larval growth after the metacestode establishment in the liver and suggest that this cytokine could be of potential value in the treatment of human alveolar echinococcosis .  相似文献   
48.
目的:建立了β-司他夫定原料有关物质的RP-HPLC测定方法和水解破坏制备系统适用性试验溶液方法。方法:采用Agilent 1100型高效液相色谱仪,使用SUPELCOSIL LC-18-DB(4.6 mm×250 mm,5μm)色谱柱,以0.01 mol·L-1醋酸铵溶液-乙腈(96.5∶3.5)和0.01 mol·L-1醋酸铵溶液-乙腈(75∶25)为流动相,梯度洗脱,检测波长254 nm,柱温25℃。结果:β-司他夫定和4种已知杂质及其他未知杂质均能达到有效分离;经水解破坏产生的α-司他夫定与β-司他夫定的分离度均达2.8;β-司他夫定、胸腺嘧啶、β-胸苷与5-O’-苯甲酰-司他夫定线性范围分别为0.51~26μg·m L-1(r=1.000)、0.13~27μg·m L-1(r=1.000)、0.50~25μg·m L-1(r=1.000)、1.7~6.3μg·m L-1(r=1.000),已知杂质胸腺嘧啶、β-胸苷与5-O’-苯甲酰-司他夫定的平均加样回收率(n=9)分别为102.8%(RSD=1.5%)、100.6%(RSD=0.9%)、101.9%(RSD=2.1%);β-司他夫定与3种已知杂质的最小检出量均在2.5 ng以下;经水解破坏制备的系统适用性溶液的重复性良好;供试品溶液在4℃下的30 h内基本稳定。结论:本方法灵敏、准确、可靠,专属性强,可用于β-司他夫定原料的有关物质测定。  相似文献   
49.
幽门螺杆菌感染对胃黏膜病理变化的影响   总被引:4,自引:1,他引:4  
背景:幽门螺杆菌(H.pylori)感染已被公认为慢性胃炎和消化性溃疡的重要危险因素,根除H.pylori能加速消化性溃疡的愈合,但其对胃黏膜病理变化的影响尚有待进一步探索。目的:了解根除H.pylori对慢性胃炎胃黏膜病理变化和癌前状态的影响。方法:采用多中心随机对照临床试验和回顾性队列研究,样本选自胃癌高发区:上海郊区的金山区和奉贤区。共纳入360例经内镜检查证实有H.pylori感染的慢性胃炎伴或不伴十二指肠溃疡患者,随机分为两组。治疗组用三联疗法(质子泵抑制剂或Hz受体阻滞剂加两种抗生素)治疗,对照组单纯慢性胃炎患者予西沙必利、十二指肠溃疡患者予西米替丁治疗。在第1年和第4年末随访胃镜,根据H.pylori是否根除将患者分为两组:H.pylori阳性组和H.pylori阴性组。所有胃黏膜活检标本由两位病理科医师统一复读。结果:至第4年末,有120例患者完成全部随访,其中H.pylori持续根除组54例,阳转组5例;H.pylori持续未根除组45例,阴转组16例。持续根除组第1年随访时,活动性炎症比例减少(P<O.05);第4年随访时,慢性炎症和肠化程度以及活动性炎症比例减少(P<O.05)。持续未根除组第1年随访时,慢性炎症程度增加(P<O.05);第4年随访时,慢性炎症和肠化程度以及活动性炎症比例增加(P<O.05),萎缩程度较第1年随访时增加(P<O.05)。结论:根除H.pylori可以减轻慢性胃炎的炎症程度,防止肠化的发生和发展。  相似文献   
50.
A male infant with perineal hypospadias and a small phallus bound in chordee is described. Biochemical investigation at age 9 months after hCG stimulation revealed a testosterone to dihydrotestosterone (DHT) ratio of 40, a markedly elevated value suggestive of deficient steroid 5 alpha-reductase activity. The diagnosis of 5 alpha-reductase deficiency was confirmed by elevated urinary 5 beta/5 alpha-steroid metabolite ratios and demonstration of defective 5 alpha-reductase activity in cultured fibroblasts from the patient's scrotum and foreskin. Application of DHT cream to the patient's abdomen raised circulating levels of DHT to the adult male range. Two courses of DHT given nightly for 3 and 4 months resulted in phallic enlargement. Surgical release of the chordee and hypospadias repair have resulted in normal male appearance of the genitalia. This case illustrates the heterogeneity of the 5 alpha-reductase deficiency phenotype.  相似文献   
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