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71.

Background  

Differential diagnosis of patients with lung infiltrates remains a challenge. Triggering receptor expressed on myeloid cells (TREM)-1 is a neutrophil and monocyte receptor up-regulated during infection. The aim of this study was to evaluate the diagnostic accuracy of TREM-1 and of C-reactive protein (CRP) from patients with lung infiltrates to discern community acquired lung infections.  相似文献   
72.

Background

Patients on long‐term maintenance hemodialysis (HD) are at high risk of developing cardiovascular disease and suffering various cardiovascular complications during HD.

Hypothesis

The purpose of this study was to evaluate the influence of changing loading conditions on the myocardial performance index (MPI) in patients on long‐term HD and to specify an optimal level of fluid loss during HD that would maintain stable global cardiac function.

Methods

The study consisted of 52 patients with end‐stage renal failure (ESRF), mean age 56±11.7 y, range: 25–80 y, on regular HD. For each patient a complete echocardiographic‐Doppler examination was performed before and after HD. Systolic and diastolic parameters of left ventricular function were measured, and the myocardial performance index (MPI) was calculated.

Results

The MPI was significantly prolonged after HD (0.47±0.15 before HD versus 0.59±0.16 after HD, p < 0.001). Mean change in body weight during HD was 2.1±0.86 kg. The MPI did not change significantly in patients with intradialytic weight loss up to 1.75 kg.

Conclusions

The MPI value seems to be independent of acute preload changes only when fluid loss is less than 1.75 kg. A 1.75‐kg fluid loss during HD seems to be the optimal goal. In ESRF patients on HD, the MPI seems to be a good indicator of global left ventricular function and potentially a valuable aid in the effort to maintain optimal fluid balance. The authors have no funding, financial relationships, or conflicts of interest to disclose.  相似文献   
73.
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   
74.
Thrombosis plays a key role in the pathophysiology of acute coronary syndromes (ACS). The management of patients with ACS includes interventional procedures and use of antithrombotic agents acutely, and dual antiplatelet therapy (aspirin and a P2Y12 receptor antagonist) for secondary prevention. However, patients with recent ACS remain at a substantial residual risk for recurrent ischemic events or death. The idea of follow-up treatment with an oral anticoagulant on top of standard therapy seems promising. Warfarin was the first oral anticoagulant thoroughly investigated in this direction, but the widespread long-term use of warfarin in ACS has been limited by challenges associated with pharmacodynamic/pharmacokinetic deficiencies of the drug and the risk of bleeding. Novel oral anticoagulants, such as direct thrombin inhibitors (DTIs) and FXa inhibitors overcome the downsides of VKAs. Ximelagatran was the first DTI, investigated and proven to be effective in prevention of recurrent ischemic events in ACS patients, but the drug association with hepatotoxicity prompted its withdrawal. Dabigatran etexilate, apixaban, darexaban (YM150) and TAK-442 were studied in phase II dose-escalation trials in order to determine the balance between clinical effectiveness and bleeding risk in daily use with dual antiplatelet therapy, with both positive and negative results. Rivaroxaban is the only agent that completed a phase III trial, showing reduction in recurrent ischemic events rate and death from cardiovascular causes as well as all-cause death. This review summarizes the data from completed and ongoing clinical trials of the new oral anticoagulants in patients with ACS.  相似文献   
75.
Stainless steel surfaces were processed by means of plasma enhanced chemical vapor deposition (PE-CVD) fed with acrylic acid vapors in order to functionalize them with carboxyl groups, which were subsequently activated for covalent immobilization of heparin-loaded (HEP) NH(2) group-functionalized (Fun) nanoliposomes (NLs). Empty Fun or HEP non-functionalized (control) NLs were used as controls. NLs were characterized for mean diameter, surface charge and heparin encapsulation/release. Different lipid compositions were used for NL construction; PC/Chol (2:1mol/mol) or PC/Chol (4:1mol/mol) (fluid type vesicles) [which allow gradual release of heparin] and DSPC/Chol (2:1mol/mol) (rigid type vesicles). Surface haemocompatibility was tested by measuring blood clotting time. Platelet adhesion on surfaces was evaluated morphologically by SEM and CLSM. The haemocompatibility of plasma-processed surfaces was improved (compared to untreated surfaces); Fun-HEP NL-coated surfaces demonstrated highest coagulation times. For short surface/blood incubation periods, surfaces coated with Fun-HEP NLs consisting of PC/Chol (2:1) had higher coagulation times (compared to DSPC/Chol NLs) due to faster release of heparin. Heparin release rate from the various NL types and surface platelet adhesion results were in agreement with the corresponding blood coagulation times. Concluding, covalent immobilization of drug entrapping NLs on plasma processed surfaces is a potential method for preparation of controlled-rate drug-eluting metallic stents or devices.  相似文献   
76.
Glycogen phosphorylase is a molecular target for the design of potential hypoglycemic agents. Structure‐based design pinpointed that the 3′‐position of glucopyranose equipped with a suitable group has the potential to form interactions with enzyme’s cofactor, pyridoxal 5′‐phosphate (PLP), thus enhancing the inhibitory potency. Hence, we have investigated the binding of two ligands, 1‐(β‐d ‐glucopyranosyl)5‐fluorouracil (GlcFU) and its 3′‐CH2OH glucopyranose derivative. Both ligands were found to be low micromolar inhibitors with Ki values of 7.9 and 27.1 μm , respectively. X‐ray crystallography revealed that the 3′‐CH2OH glucopyranose substituent is indeed involved in additional molecular interactions with the PLP γ‐phosphate compared with GlcFU. However, it is 3.4 times less potent. To elucidate this discovery, docking followed by postdocking Quantum Mechanics/Molecular Mechanics – Poisson–Boltzmann Surface Area (QM/MM‐PBSA) binding affinity calculations were performed. While the docking predictions failed to reflect the kinetic results, the QM/MM‐PBSA revealed that the desolvation energy cost for binding of the 3′‐CH2OH‐substituted glucopyranose derivative out‐weigh the enthalpy gains from the extra contacts formed. The benefits of performing postdocking calculations employing a more accurate solvation model and the QM/MM‐PBSA methodology in lead optimization are therefore highlighted, specifically when the role of a highly polar/charged binding interface is significant.  相似文献   
77.
78.

Background  

Treatment of distal tibial intra-articular fractures is challenging due to the difficulties in achieving anatomical reduction of the articular surface and the instability which may occur due to ligamentous and soft tissue injury. The purpose of this study is to present an algorithm in the application of external fixation in the management of intra-articular fractures of the distal tibia either from axial compression or from torsional forces.  相似文献   
79.
Classical interferon-alpha has been shown to be correlated with the development of a variety of autoimmune disorders. A 38 year-old female patient developed simultaneously diabetic ketoacidosis and hyperthyroidism 5 mo following initiation of treatment with pegylated interferon-α and ribavirin for chronic hepatitis C. High titers of glutamic acid decarboxylase, antinuclear and thyroid (thyroid peroxidase and thyroglobulin) antibodies were detected. Antiviral treatment was withdrawn and the patient was treated with insulin for insulin-dependent diabetes mellitus and propranolol for hyperthyroidism. Twelve months after cessation of pegylated interferon-α therapy the patient was euthyroid without any medication but remained insulin-dependent.  相似文献   
80.
Although autopsy series report liver granulomas in up to 70% of patients, computed tomography detection of hepatic and splenic lesions is described in 5% and 15% of sarcoidosis cases, respectively. A rather rare case of liver sarcoidosis mimicking macronodular cirrhosis is presented by this current article. Imaging findings in our patient were in compliance with the diagnosis of liver cirrhosis, although liver biopsy findings eventually revealed sarcoid granulomas located in the portal and lobular areas without fibrotic lesions. Histological and imaging modalities in liver sarcoidosis are discussed.  相似文献   
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