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21.
Oesophageal duplications are rare congenital abnormalities. Most of them do not communicate with the oesophageal lumen. We present a very uncommon finding of communicating oesophageal duplication in which the connection between the oesophagus and its duplicate portion was demonstrated by CT.  相似文献   
22.
EXACERBATIONS DURING PREGNANCY: Clinical and experimental data have clearly evidenced the influence of hormones on the course of systemic lupus erythematosus. In prospective studies of pregnant women, an exacerbation is observed in 57% to 60% of the cases. It can be severe in 10% of the cases and occur in the post partum in 7%. For most patients, the exacerbation is moderate and has no unfavorable effect on the outcome of pregnancy. In case of renal involvement, it is difficult to differentiate an intricated HELPP syndrome. MARKERS AND RISK FACTORS: Low complement and elevated anti-DNA levels are distinctive markers. Earlier renal involvement and hypertension are important prognostic factors, particularly when the lupus begins during pregnancy. However, when serum creatinine is lower than 100 mumol/l at pregnancy onset in patients in remission, pregnancy does not alter renal function. An association with antiphospholipid antibodies increases the risk for the fetus and the kidney function. TREATMENT: Optimal treatment remains to be defined. Commonly, patients are given aspirin, heparin in case of a history of thromboembolism, or both. The rate of success currently exceeds 70%. The risk of thromboembolism in the peri or post partum period requires anticoagulant treatment. Outside pregnancy: Ovulation induction raises two risks: triggering a lupus flare-up and thrombosis, particularly for patients with antiphospholipid antibodies. The influence of menopause and hormone replacement therapy remains poorly understood.  相似文献   
23.
A FREQUENT OCCURRENCE: Dermatological manifestations are frequently observed in patients with relapsing polychondritis. However, they have not been extensively studied as polychondritis is a rare disease and the reported dermatological manifestations appear to be nonspecific. A WIDE SPECTRUM: The most frequently observed manifestations are aphthosis with sometimes complex aphthosis, nodular papular or purpuric lesions. Neutrophilic dermatosis has been reported in isolated cases. Histologically, these lesions correspond to nonspecific inflammatory infiltrates, vasculitis or thrombosis. Various pathological findings are observed in nodular lesions. RELATED AND OVERLAP CONDITIONS: Similar dermatological manifestations occur in Beh?et's syndrome and in inflammatory bowel diseases. Patients with relapsing polychondritis and myelodysplasia very frequently have dermatological manifestations. Repeated blood cell determinations are therefore necessary in patients with relapsing polychondritis and dermatological manifestations.  相似文献   
24.
Leavitt  SA; DeAngelo  AB; George  MH; Ross  JA 《Carcinogenesis》1997,18(11):2101-2106
Dichloroacetic acid (DCA) is a chlorination byproduct found in finished drinking water. When administered in drinking water this chemical has been shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over the animal's lifetime. In this study, we investigated whether mutant frequencies were increased in mouse liver using treatment protocols that yielded significant tumor induction. DCA was administered continuously at either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice harboring the bacterial lacI gene. Groups of five or six animals were killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of treatment, there was no significant difference in mutant frequency between the treated and control animals at either dose level. At 60 weeks, mice treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60 weeks had a 2.3-fold increase in mutant frequency over the concurrent controls (P = 0.002). The mutation spectrum recovered from mice treated with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%) and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T transitions comprised 53.19% of the recovered mutants among control animals. Although only 19.15% of mutations among the controls were at T:A sites, 32.79% of the mutations from DCA-treated animals were at T:A sites. This is consistent with the previous observation that the proportion of mutations at T:A sites in codon 61 of the H-ras gene was increased in DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates DCA-associated mutagenicity in the mouse liver under conditions in which DCA produces hepatic tumors.   相似文献   
25.
BACKGROUND: The informed consent procedure plays a central role in randomised controlled trials but has only been explored in a few studies on children. AIM: To assess the quality of the informed consent process in a paediatric setting. METHODS: A questionnaire was sent to parents who volunteered their child (230 children) for a randomised, double blind, placebo controlled trial of ibuprofen syrup to prevent recurrent febrile seizures. RESULTS: 181 (79%) parents responded. On average, 73% of parents were aware of the major study characteristics. A few had difficulty understanding the information provided. Major factors in parents granting approval were the contribution to clinical science (51%) and benefit to the child (32%). Sociodemographic status did not influence initial participation but west European origin of the father was associated with willingness to participate in future trials. 89% of participants felt positive about the informed consent procedure; however, 25% stated that they felt obliged to participate. Although their reasons for granting approval and their evaluation of the informed consent procedure did not differ, relatively more were hesitant about participating in future. Parents appreciated the investigator being on call 24 hours a day (38%) and the extra medical care and information provided (37%) as advantages of participation. Disadvantages were mainly the time consuming aspects and the work involved (23%). CONCLUSIONS: Parents' understanding of trial characteristics might be improved by designing less difficult informed consent forms and by the investigator giving extra attention and information to non-west European parents. Adequate measures should be taken to avoid parents feeling obliged to participate, rather than giving true informed consent.  相似文献   
26.
27.
1-取代吡唑烷酮类抗惊构效关系的研究   总被引:5,自引:0,他引:5  
1-正癸基吡唑烷-3-酮(Ⅱ结构式见表1)是欧洲专利报道的一种新型减肥剂。White等报道该化合物可通过血脑屏障,并对γ-氨基丁酸氨基转移酶(GABA-T)有强烈的抑制活性,但对谷氨酸脱羧酶的抑制作用较弱,因此可引起脑内γ-氨基丁酸(GABA)水平的升高,故我们相信应有抗惊活性。经我们合成后,发现Ⅱ确有良好的抗癲痫活性,抗小鼠最大电  相似文献   
28.
报道了β-阻滞剂塞利洛尔的简便制备方法,即以对乙氧基苯胺为原料,经酰胺化,傅克反应,以环氧氯丙烷取代,最后用叔丁胺直接与环氧基反应开环等4步反应制得。比文献五步反应缩短了一步,产物经元素分析、红外光谱、核磁共振谱、质谱等分析确定结构。  相似文献   
29.
30.
Objectives: Informal caregivers who recognize patients’ depressive symptoms can better support self-care and encourage patients to seek treatment. We examined patient-caregiver agreement among patients with heart failure (HF). Our objectives were to (1) identify distinct groups of HF patients and their out-of-home informal caregivers (CarePartners) based on their relationship and communication characteristics, and (2) compare how these groups agree on the patients’ depressive symptoms.

Method: We used baseline data from a comparative effectiveness trial of a self-care support program for veterans with HF treated in outpatient clinics from 2009-2012. We used a cross-sectional design and latent class analysis (LCA) approach to identify distinct groups of patient-CarePartner dyads (n?=?201) based on relationship and communication characteristics then evaluated agreement on patients’ depressive symptoms within these groups.

Results: The LCA analysis identified four groups: Collaborative (n?=?102 dyads, 51%), Avoidant (n?=?33 dyads, 16%), Distant (n?=?35 dyads, 17%), and Antagonistic (n?=?31 dyads, 15%). Dyadic agreement on the patients’ depressive symptoms was highest in the Distant (Kappa (κ)?=?0.44, r?=?0.39) and Collaborative groups (κ?=?0.19, r?=?0.32), and relatively poor in the Avoidant (κ?=?–0.20, r?=?0.17) and Antagonistic (κ?=–0.01, r?=?0.004) groups. Patients in Avoidant (61%) and Antagonistic groups (74%) more frequently had depression based on self-report than patients in Collaborative (46%) and Distant (34%) groups.

Conclusion: Caregiver relationships in HF tend to be either Collaborative, Avoidant, Distant, or Antagonistic. Patients’ depressive symptoms may negatively affect how they communicate with their caregivers. At the same time, improved patient-caregiver communication could enhance dyadic consensus about the patient’s depressive symptoms.  相似文献   

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