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61.
Persistent airway inflammation may require the use of different markers for monitoring airway inflammation. In this study, the authors investigated whether adenosine, which may be produced in allergic inflammatory conditions, could be measured with good reproducibility in exhaled breath condensate (EBC), and whether its concentration was elevated in patients with asthma. EBC adenosine and exhaled nitric oxide (eNO), a noninvasive marker of asthmatic airway inflammation, were measured in 40 healthy volunteers and 43 patients with allergic bronchial asthma. Repeatability of adenosine measurement was checked in 20 pairs of samples collected from healthy control subjects. Adenosine was detectable in all EBC samples by the applied high-performance liquid chromatographic method. The mean difference between repeated measurements of adenosine was -0.1 nM and all differences were within the coefficient of repeatability. Adenosine concentration was higher in steroid-naive patients (n=23) compared with healthy control subjects and steroid-treated patients (n=20). In patients with worsening symptoms of asthma (n=23), adenosine concentration was elevated compared with those in a stable condition (n=20). Furthermore, adenosine concentrations were related to eNO levels in asthmatic patients. These results, showing good reproducibility of adenosine measurements and increased adenosine concentrations in steroid-naive patients and in patients with worsening of asthmatic symptoms, indicate that adenosine measurement in exhaled breath condensate might be an acceptable novel method to investigate the role of local production of adenosine in the airways.  相似文献   
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The recent increase in the incidence of ectopic pregnancies was associated with rapid improvement in the diagnostic and therapeutic techniques. Quantitative serum B-HCG radioimmunoassay and high resolution vaginal ultrasonography have facilitated early diagnosis of ectopic pregnancy allowing a more conservative approach to patient management. Different conservative surgical and medical lines of management recently developed were associated with and increased chance of subsequent intrauterine pregnancy with no increase in the incidence of repeat ectopic pregnancy. Outpatient systemic medical treatment seems to be a preferred alternative to conservative surgery. In selected cases, it is associated with a lower complication rate and promising result for fertility. (Br J Clin Pract 1996; 50(7) : 376-380.)  相似文献   
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H. pylori infection has recently been associated with various vascular disorders. The aim of this study was to investigate its role in primary headache, a pathology strictly associated with vascular alterations. A total of 200 subjects affected by primary headache were evaluated. H. pylori infection was diagnosed by the 13C urea breath test. Headache was classified in tension-type headache, cluster headache, and migraine with or without aura. Prevalence of H. pylori infection and gastrointestinal (GI) symptoms were evaluated. H. pylori infection was found in 40% of the patients; prevalence of migraine without aura was found to be significantly greater in infected patients. The positive group showed no significant differences in the prevalence of the GI symptoms evaluated. In 30 infected patients, it was assessed whether the eradication of the bacterium was able to reduce frequency, intensity, and duration of clinical attacks of headache. After eradication, clinical attacks of headache completely disappeared in 17% of patients. Moreover, intensity, duration, and frequency of headache attacks were reduced in 69% of the remaining subjects. In conclusion, H. pylori infection is common in primary headache; bacterium eradication appears to be related to a significant reduction in clinical attacks of the disease.  相似文献   
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We describe a patient with angioimmunoblastic lymphadenopathy with dysproteinemia (AILD), who subsequently developed large-cell immunoblastic lymphoma of B-cell immunophenotype. At the time of the initial diagnosis, histologic examination of an inguinal lymph node showed typical features of AILD, and there was no evidence of a monoclonal B-cell population by immunohistochemical analysis. In situ hybridization and Southern blot analysis for Epstein-Barr virus (EBV) were negative. At autopsy 2 years later, the patient had widespread lymph node and organ involvement by large-cell immunoblastic lymphoma of B-cell immunophenotype. Southern blot analysis performed on DNA extracted from lymph nodes, liver, and spleen showed two patterns of Ig heavy chain and kappa light chain gene rearrangements. The T-cell receptor beta chain gene was in the germline configuration. Analysis with an EBV terminal repeat region probe showed two clonal populations that paralleled the Ig gene rearrangement studies. Double-labeling immunohistochemistry and in situ hybridization confirmed the presence of EBV within the neoplastic B cells. The data support the hypothesis that EBV was not etiologically related to AILD in this case, and that EBV proliferation may occur after the onset of the disease. Further, the data suggest that some B-cell lymphomas that arise in the setting of AILD resemble EBV-associated B-cell lymphomas that arise in other immunodeficiency states.  相似文献   
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We studied the effect of recombinant human granulocyte colony- stimulating factor (rhG-CSF) administration to pregnant rats upon fetal and neonatal myelopoiesis. Pregnant rats were treated with rhG-CSF twice daily for 2, 4, and 6 days before parturition. rhG-CSF crossed the placenta and reached peak fetal serum concentrations 4 hours after administration. Peak fetal serum levels were 1,000-fold lower than levels detected in the dam. Hematopoietic effects of rhG-CSF were assessed by cytologic analysis of the newborn blood, spleen, bone marrow, thymus, and liver. White blood cell counts were increased twofold to fourfold in newborns. This increase was due to circulating numbers of polymorphonuclear cells (PMN). rhG-CSF induced a myeloid hyperplasia in the newborn marrow consisting of immature and mature myeloid cells in the day-2 and day-4 treated pups. Bone marrow of pups treated for 6 days contained mostly hyper-segmented PMN with little or no increase in myeloid precursors. An increase in the number of postmitotic (PMN, bands, and metamyelocytes) and mitotic (promyeloblasts, myeloblasts, and metamyeloblasts) myeloid cells in the spleen of neonates was observed. No change was detected in splenic lymphocytes or monocytes. No effect of rhG-CSF was noted in the newborn liver or thymus. These results demonstrate that maternally administered rhG-CSF crosses the placenta and specifically induces bone marrow and spleen myelopoiesis in the fetus and neonate. The significant myelopoietic effects of rhG-CSF at low concentrations in the fetus suggest an exquisite degree of developmental sensitivity to this cytokine and may provide enhanced defense mechanisms to the neonate.  相似文献   
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The in vivo behaviour of well-defined immune complexes in rats was studied using complexes derived from DNP-conjugated bovine thyroglobulin (DNP-BTG) and purified specific goat anti-DNP IgG. Both clearance and glomerular localization were mainly dependent on the nature of the antigen. Soluble immune complexes formed with DNP17-BTG were cleared faster and showed a more marked localization in the glomerular mesangium than complexes formed with DNP3.4-BTG. A slight increase in the antibody to antigen ratio seemed to facilitate mesangial localization of soluble immune complexes. Insoluble immune complexes showed temporary localization as microemboli in the lumina of glomerular and peritubular capillaries. This study thus shows that not only the size and composition of the complexes but also the nature of the antigen within the complex can influence the clearance and organ localization of circulating immune complexes.  相似文献   
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神经外科中高渗盐注射液应用研究进展   总被引:1,自引:0,他引:1  
控制脑水肿和颅内压(ICP)升高是神经外科围手术期治疗的重要组成部分.颅脑创伤、动脉梗塞、静脉高压/梗塞、大脑内出血、蛛网膜下腔出血、肿瘤和术后脑组织水肿的治疗过程中ICP的控制都是决定患者预后的关键因素.虽然利用渗透压脱水药物是控制ICP的最基础的工具,但却缺乏前瞻性研究以指导其运用,高渗盐被认为是甘露醇的替代物,早期的数据表明每种药的用药指征最终取决于ICP的病因.在这篇综述中,我们总结了有关高渗盐(HS)治疗颅内高压的相关数据,以及这些数据和我们有关HS的经验是如何指导目前的ICP治疗的.  相似文献   
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