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81.
BACKGROUND: Compressive hematoma after thyroidectomy is a rare complication (1%) but can potentially be severe. The aim of this study was to search for risk factors, in particular the use of anticoagulants or antiplatelet medication, and to see if the delay of hematoma formation would require 1-day surgery performed in a careful manner. MATERIALS AND METHODS: Retrospective review of 6,830 patients undergoing thyroidectomy in a single institution (1991 to 2006) identified 70 patients with hematomas requiring reoperation. Case controls (210 patients) were matched for age, gender, year of operation, type of thyroid disease, and type of operation. The notion of anticoagulant or antiplatelet medication was particularly studied. The delay of hematoma formation and the cause of bleeding were studied in univariate analysis by a chi-squared test and a Fischer's test. RESULTS: In univariate analysis, the formation of hematoma is not related to age, gender, type of thyroid disease, or type of bleeding. The pre or intraoperatory administration of anticoagulant or antiplatelet medication did not influence hematoma formation. Thirty-seven hematomas (53%) presented within 6 h postoperatively, 26 (37%) between 7 and 24 h and seven (10%) beyond 24 h. CONCLUSION: Patients undergoing anticoagulant or antiplatelet treatment are not a high-risk population for hematoma formation. Forty-seven percent of the patients presented postoperative hematomas beyond 6 h postoperatively, leading to the conclusion that 1-day surgery is not safe.  相似文献   
82.
Dirofilaria repens (formerly Dirofilaria conjunctiva ) is a natural parasite of the subcutaneous tissues of dogs, cats and wild carnivores in Europe, Africa and Asia. Microfilariae are transmitted to humans by various species of mosquito. An autochthonous case of subcutaneous dirofilariasis is reported in a Greek patient from the island of Corfu. The clinical manifestation of the infection was a palpable, painless, subcutaneous nodule in the region of the groin, which 2 days before the patient consulted the doctor developed symptoms and signs of inflammation (pain, edema and redness). The entire lesion was surgically removed, and the nematode worm D. repens was identified on histological sections of biopsy material. The aim of this report was (a) to describe the microscopic morphological features of D. repens that enable identification of the parasite on histological examination and (b) to emphasize the importance of consideration of subcutaneous dirofilariasis in the differential diagnosis of subcutaneous nodules with inflammatory eosinophilic infiltration in countries where the infection is endemic.  相似文献   
83.
Classic inotropic agents provide short-term haemodynamic improvement in patients with heart failure, but their use has been associated with poor prognosis. A new category of inotropic agents, the Ca(2+) sensitizers, may provide an alternative longer lasting solution. Levosimendan is a relatively new Ca(2+) sensitizer which offers haemodynamic and symptomatic improvement by combining a positive inotropic action via Ca(2+) sensitization and a vasodilatory effect via adenosine triphosphate(ATP)-sensitive K(+) (K(ATP)), Ca(2+)-activated K(+) (K(Ca)(2+)) and voltage-dependent K(+) (K(V)) channels activation. Levosimendan also seems to induce a prolonged haemodynamic improvement in patients with heart failure as a result of the long half-life of its active metabolite, OR-1896. Furthermore, there is also evidence that levosimendan may have additional antiinflammatory and antiapoptotic properties, affecting important pathways in the pathophysiology of heart failure. Despite the initial reports for a clear benefit of levosimendan on short- and long-term mortality in patients with severe heart failure, the results from the recent clinical trials are rather disappointing, and it is still unclear whether it is superior to dobutamine in affecting survival of patients with severe heart failure. In conclusion, levosimendan is a promising agent for the treatment of decompensated heart failure. As further to its positive inotropic effect, it affects multiple pathways with key roles in the pathophysiology of heart failure. The results of the ongoing trials examining the effect of levosimendan on mortality in patients with heart failure will hopefully resolve the controversy as to whether levosimendan is superior to classic inotropic agents for the treatment of severe heart failure.  相似文献   
84.
The basic physiological and anatomical basis for circadian rhythms in mammalian behaviour and physiology is introduced. The pathways involved in photic entrainment of the circadian clock are discussed in relation of new findings that identify the molecules that are involved in signalling between the environment and the clock. The molecular basis of endogenous cycles is described in the mouse, and compared to the mechanism that is present in the fly. Finally we speculate on the relationship between circadian physiology and pain.  相似文献   
85.
The development of non-invasive immunisation procedures is a top priority for public health agencies when it is realised that the current immunisation practices are unsafe, particularly in developing countries due to the widespread reuse of non-sterile syringes. There is a risk of abscess formation resulting in impairment of meat quality or the value of the hide, and the risk of transmission of infectious diseases when vaccines are administered to food animals by injection. Recently, the skin has emerged as an alternative route for non-invasive delivery of vaccines. Topical application of various types of antigens (mainly proteins and toxoids) with an adjuvant resulted in the induction of systemic and mucosal immune responses. However, due to skin barrier constraints and the physicochemical properties of large molecular weight proteins, the immune responses are variable and require further optimisation. Small molecular size synthetic peptides when applied onto bare skin with an adjuvant are effective immunogens, inducing both humoral and cellular immune responses. Their use as vaccines offers considerable advantages over conventional preparations in terms of safety, purity, stability, availability and cost. Therefore, they could be the most suitable candidate immunogens for skin immunisation. This review describes our recent observations on the immunogenicity of synthetic peptides applied onto bare skin in relation to vaccination.  相似文献   
86.
Objective: Tetrahydrobiopterin (BH4) is the essential cofactor of endothelial nitric oxide synthase (eNOS) and intracellular levels of BH4 is regulated by oxidative stress. The aim of this paper was to describe the influence of exogenous endothelin-1 on intracellular BH4 and its oxidation products dihydrobiopterin (BH2) and biopterin (B) in a wide range of vascular tissue.

Design: Segments of internal mammary artery (IMA) and human saphenous vein (SV) from 41 patients undergoing elective surgery were incubated in ET-1 (0.1?μM). Aorta and lung from transgenic mice overexpressing ET-1 in the endothelium (ET-TG) were analysed with regards to intracellular biopterin levels. Human umbilical vein endothelial cells (HUVEC) were incubated in ET-1 (0.1?μM) and intracellular biopterin levels were analysed. From 6 healthy women undergoing caesarean section, subcutaneous fat was harvested and the resistance arteries in these biopsies were tested for ET-mediated endothelial dysfunction.

Results: In HUVEC, exogenous ET-1 (0.1?μM) did not significantly change intracellular BH4, 1.54?±?1.7 vs 1.68?±?1.8?pmol/mg protein; p?=?.8. In IMA and SV, exogenous ET-1(0.1?μM) did not change intracellular BH4 n?=?10, p?=?.4. In aorta from wild type vs ET-TG mice there was no significant difference in intracellular BH4 between the groups: 1.3?±?0.49 vs 1.23?±?0.3?pmol/mg protein; p?=?.6. In resistance arteries (n?=?6) BH4 together with DTE (an antioxidant) was not able to prevent ET-mediated endothelial dysfunction.

Conclusion: ET-1 did not significantly alter intracellular tetrahydrobiopterin levels in IMA, SV, HUVEC or aorta from ET-TG mice. These findings are important for future research in ET-1 mediated superoxide production and endothelial dysfunction.  相似文献   
87.
Kikuchi-Fujimoto disease is a form of reactive lymphadenopathy, which was firstly described in Japan, but is uncommon in the Western world. We retrospectively reviewed the medical records of nine cases of adult or adolescent Kikuchi’s disease diagnosed in a single Haematology Unit in Athens, Greece between 1990 and 2006. The median age of the patients was 25 years (14–40) and 8/9 were females. All patients presented with cervical lymphadenopathy sparing the supraclavicular fossa; one had associated axillary lymphadenopathy, seven had fever and two were asymptomatic. The median duration of lymphadenopathy before presentation was 30 days (10–45). Just palpable splenomegaly was recorded in three patients. The median value of the maximal lymph node diameter was 2 cm (1–5) and only 1/9 had nodes >2 cm in their largest diameter. Lymphadenopathy was tender in two patients; hard nodes were observed in three patients. The median leukocyte count was 4.7 × 109/l (2.2–4.9) with a normal differential in 7/9 patients. No infectious agent could be demonstrated. One patient had clinical and laboratory evidence of primary antiphospholipid syndrome (APLS). In conclusion, Kikuchi’s disease represents a rare but important diagnostic possibility for patients presenting with lymphadenopathy in Greece and other western countries. In this setting, autoimmune disorders, mainly lupus and APLS, should be considered and excluded by the appropriate laboratory work-up.  相似文献   
88.
Background and rationale. It is well established that chronic viral hepatitis (CVH) negatively affects patients’ health-related quality of life (HRQOL). The aim of the present study was to assess the extent to which fatigue and depressive symptoms are associated with CVH patients’ HRQOL.Methods. Eighty-four adult CVH outpatients [45 with hepatitis B virus (HBV) and 39 with hepatitis C virus (HCV) infection] participated in the study. The Short Form-36 Health Survey (SF-36), the Beck Depression Inventory-II (BDI-II) and the Fatigue subscale of the Functional Assessment of Cancer Therapy-Anemia Scale (FACT-F) were used to assess HRQOL, depression and fatigue, respectively.Results. All aspects of HRQOL perceived by CVH patients were significantly impaired compared to the general population, as a comparison with Greek population-based normative data revealed. HBV patients presented similar HRQOL with HCV patients. Clinical parameters including infection activity, fibrosis stage or inflammation grade, as well as depressive symptoms and fatigue were found to be significantly associated with HRQOL. Multivariate analyses showed that older age (p <0.001) and higher fatigue scores (p <0.001) were the variables most closely associated with the physical HRQOL, whereas higher rates on depressive symptoms (p <0.0005) and fatigue (p <0.020) scales were the variables most closely associated with the mental HRQOL.Conclusions. In conclusion, CVH is associated with impaired HRQOL. Fatigue and impaired psychological functioning is associated with diminished HRQOL in CHV, independent of the disease etiology. Consequently, management of fatigue and depressive symptoms should be considered a priority, in order to improve HRQOL in CVH patients.  相似文献   
89.
90.
Persistent oxidative stress in the vascular wall may lead to endothelial dysfunction, a pathological process widely implicated in the morbidities observed in a spectrum of cardiovascular disease. The production of reactive oxygen species (ROS) is regulated by various oxidase enzymes and mitochondrial electron transport mechanisms. Nitric oxide (NO) is a key mediator of endothelial function via its effect on endothelium dependent vascular relaxation. Therapeutic interventions aimed to increase NO bioavailability in the vasculature may improve the long term cardiovascular outcome for healthy individuals, high-risk subjects, and patients with advanced atherosclerosis. Current therapeutic strategies focus on enhancing synthesis or lowering oxidative inactivation of NO in human vasculature. Of the available therapeutic agents, angiotensin converting enzyme inhibitors and statins have shown most promise at improving endothelial function and cardiovascular outcome after long term administration. Other therapeutic approaches may also be useful towards improving endothelial dysfunction. These strategies include targeting NO synthesis by modulation of endothelial nitric oxide synthase (eNOS) coupling, such as folates and tetrahydrobiopterin. Evidence for the benefits of gene therapy to improve endothelial function is also emerging. However, the long term direct clinical benefit of these strategies aimed to improve endothelial function still remains unclear.  相似文献   
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