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1.
《Hemoglobin》2013,37(5):371-395
Abstract

The levels of the inactive hemoglobin (Hb) pigments [such as methemoglobin (metHb), carboxyhemoglobin (HbCO) and sulfohemoglobin (SHb)] and the active Hb [in the oxyhemoglobin (oxyHb) form] as well as the blood Hb concentration in healthy non pregnant female volunteers were determined using a newly developed multi-component spectrophotometric method. The results of this method revealed values of SHb% in the range (0.0727–0.370%), metHb% (0.43–1.0%), HbCO% (0.4–1.52%) and oxyHb% (97.06–98.62%). Furthermore, the results of this method revealed values of blood Hb concentration in the range (12.608–15.777?g/dL). The method is highly sensitive, accurate and reproducible.  相似文献   

2.
目的观察山东省慢型、潜在型克山病患者的临床特点和血管内皮功能,探讨机体内皮功能失调与克山病发生发展的关系。方法选择慢型、潜在型克山病患者57人、病区健康人34人,分别采集清晨空腹血检测ET、NO、NOS、iNOS及cNOS含量及活性。结果(1)克山病患者ET水平明显高于病区健康人(P<0.01);心功能越差,ET升高越明显(P<0.01);(2)NO和NOS含量,潜在型、慢型克山病均明显高于病区健康人(P<0.01);慢型高于潜在型(P<0.01);iN-OS含量克山病患者也高于病区健康人(P<0.05);慢型克山病高于潜在型克山病(P<0.05)。结论ET、NO水平的变化可能作为一种中间环节参与了克山病的发病机制;心功能不同,血浆ET、NO升高的程度也不同;ET、NO可作为克山病病情严重程度的预测指标。  相似文献   

3.
Halestrap  Andrew P.  Kerr  Paul M.  Javadov  Sabzali  Suleiman  Saadah 《Sepsis》1999,2(4):312-325
The mitochondrial permeability transition (MPT) occurs when a non-specific pore opens in the inner mitochondrial membrane and converts the mitochondrion from an organelle whose ATP production sustains the normal function of the cell to an instrument of death. Conditions favouring the MPT including high [Ca2+], oxidative stress and adenine nucleotide depletion, all of which occur when a tissue is reperfused following a period of ischemia. Cyclosporin A (CsA) and low pH (<7.0) are potent inhibitors of the MPT. Methods have been devised to demonstrate directly that the MPT pores open upon reperfusion but not during ischemia. The mechanism of the MPT appears to involve binding of mitochondrial cyclophilin (CyP) to the adenine nucleotide translocase (ANT) followed by a calcium-mediated conformational change that converts the ANT into a non-specific pore. Understanding the molecular mechanism has assisted in devising strategies that can be used to protect tissues from damage caused by reperfusion injury. These might also be of benefit in the prevention of multiple organ failure for which reperfusion injury of the gut is thought to be the initial trigger. Protective regimes include the pretreatment of tissues prior to ischemia/reperfusion with CsA (binds to CyP), free radical scavengers that reduce oxidative stress (e.g., pyruvate and propofol) and agents that decrease pHi (e.g., pyruvate or amelioride derivatives). Reperfusion injury can produce both immediate cell death by necrosis or delayed apoptotic cell death and it appears that the mitochondria determine which route is taken. Prolonged opening leads to rapid cell death by necrosis, whilst transient opening leads to cytochrome c release and subsequent apoptosis hours or days later.  相似文献   

4.
The aim of this study was to evaluate the accuracy of procalcitonin (PCT) in predicting infective endocarditis (IE). 23 adult patients with IE, 30 patients with sepsis and 30 with tick-borne encephalitis were included in this prospective study. The PCT serum level, C-reactive protein (CRP), total leukocyte, and immature polymorphonuclear (PMN) cell counts were determined on admission, prior to the institution of antibiotic therapy, and compared according to the diagnosis. The median PCT level in patients with IE endocarditis was 0.81 ng/ml, in patients with sepsis it was 43.74 ng/ml, and in the group with viral infection it was 0.25 ng/ml (P < 0.001). The highest PCT level was found in patients with Staphylococcus aureus endocarditis. The area under the receiver operating characteristic curve that used PCT to predict IE was 0.722 (95% CI 0.572–0.873), compared with 0.909 (95% CI 0.829–0.989) for CRP, 0.699 (95% CI 0.551–0.846) for immature PMN cell count, and 0.619 (95% CI 0.468–0.770) for leukocyte count. Our study fails to demonstrate superiority of PCT as a diagnostic laboratorial parameter in predicting IE compared to CRP.  相似文献   

5.
We investigated the expression of membrane-type matrix metalloproteinase (MT-MMP) and matrix metalloproteinase (MMP) mRNAs in synovial tissue from patients with rheumatoid arthritis (RA, n = 5) or osteoarthritis (OA, n = 5) by Northern blot analysis. Northern analysis demonstrated strong expression of MT1-MMP, MT3-MMP, MMP-1, and MMP-3 and weak expression of MT2-MMP and MMP-8 in synovial tissue from patients with RA or OA. MT4-MMP was not detected. No significant difference was shown in the expression of MT-MMP mRNAs between RA and OA. Synovial tissue of RA or OA patients expressed MT-MMPs as well as MMPs. These results indicate that, in addition to MMPs, MT1-MMP, MT3-MMP, and probably MT2-MMP may play a role in the degradation of bone and cartilage matrix in RA and OA. Such information may provide a clue to the development of a novel therapeutic approach targeted on the prevention of joint destruction. Received: April 30, 2000 / Accepted: September 19, 2000  相似文献   

6.

Background

Recent advances in computer graphics and wireless technologies have renewed interest in vectorcardiogram (VCG) signals that use fewer leads than the conventional 12-lead electrocardiogram (ECG) signals for medical diagnostic applications. However, most cardiologists are accustomed to the 12-lead ECG even though some of the leads are either nearly aligned with or derived from the others and consequently contain redundant information. The ability to transform from orthogonal 3-lead VCG to 12-lead ECG enables the use of fewer leads for signal analysis, computer visualization, and wireless transmission of signals. This can also improve mobility, albeit limited, to the patients.

Materials and Methods

We present a statistical approach to transform 3-lead Frank VCG to 12-lead ECG signals and vice versa, based on Dower's pioneering work on lead tranformation. This approach enables compensation of baseline shifts and other constant biases present in long ECG data streams, so that the resulting statistical transforms can be more consistent and accurate. We compare the performance of the affine transform with that of Dower transform (from 3 to 12 and from 12 to 3) using the data from the PhysioNet PTB database.

Results

The results show that for both myocardial infarction (MI) and healthy control (HC) subjects, the statistical affine transform presented here maps 3-lead VCG to12-lead ECG more accurately than Dower or other lead transformation matrices of the ECG recordings.

Discussion

This investigation also shows the limitations associated with single dipole assumption that underlies Dower's geometric transformation. The results also indicate that lead transformation accuracy can be improved using separate customized transforms to, for example, age or pathologic conditions (here, MI vs HC) than a single statistical or geometric transform. Pertinently, we find that the affine transform coefficients can serve as discriminating features for classification/discrimination of MI patients from HC subjects.  相似文献   

7.
The HPV viral lifecycle is tightly linked to the host cell differentiation, causing difficulty in growing virions in culture. A system that bypasses the need for differentiating epithelium has allowed for generation of recombinant particles, such as virus-like particles (VLPs), pseudovirions (PsV), and quasivirions (QV). Much of the research looking at the HPV life cycle, infectivity, and structure has been generated utilizing recombinant particles. While recombinant particles have proven to be invaluable, allowing for a rapid progression of the HPV field, there are some significant differences between recombinant particles and native virions and very few comparative studies using native virions to confirm results are done. This review serves to address the conflicting data in the HPV field regarding native virions and recombinant particles.  相似文献   

8.
Interstitial pneumonitis (IP) associated with polymyositis and dermatomyositis (PM/DM) is a serious complication that affects prognosis. We therefore undertook a retrospective multicenter study to examine the efficacy of a combination treatment with cyclosporin A (CsA) and corticosteroids. Fifty-three IP patients with PM/DM (9 PM, 44 DM) were analyzed. Thirty-two patients treated with CsA plus corticosteroids (9 PM, 23 DM) were included in the study. Four parameters, i.e., subjective symptoms, ausculatory sound, chest radiographs, and respiratory index, were serially evaluated. A general evaluation was performed 4 weeks after the start of the combination treatment. All patients with PM and chronic IP with DM, and 52% of those with acute IP with DM were graded as better than partially effective in the general evaluation. In contrast, all patients graded as progressive in the general evaluation had acute IP with DM. It is of note that in acute IP with DM, the survival rate of the group primarily treated with CsA and corticosteroids from the early stage of their disease was significantly higher than that of the group initially treated with corticosteroids alone (P = 0.049). In conclusion, a combination treatment of CsA and corticosteroids from the early stage of disease may be advantageous for patients with IP with PM/DM, especially acute IP with DM.  相似文献   

9.
Endocavitary Structures and Ventricular Tachycardia Ablation. Background: Radiofrequency (RF) ablation for ventricular tachycardia (VT) has high failure rates. Whether endocavitary structures (ECS) such as the papillary muscles (PMs), moderator bands (MBs), or false tendons (FTs) impact VT ablation is unknown. Methods and Results: We retrospectively reviewed records of 190 consecutive patients presenting for VT ablation and identified 46 (24%) where ECS affected ablation. In 31 of 46 patients (67%), the ECS created difficulty with catheter manipulation (n = 20), interpretation of pace map data (n = 7), or with accurately defining a scar (n = 4). In 15 of 46 (33%), specific mapping and RF energy delivery targeting the ECS itself was necessary to eliminate the arrhythmia. Detailed electroanatomic mapping was performed in 11 of 15 (73%), noncontact mapping in 3 of 15 (20%), multielectrode catheter mapping in 1 of 15 (7%), and intracardiac ultrasound in 14 of 15 (93%) patients. The ablated ECS was a PM in 5 of 15, the MB in 7 of 15, and an FT in 3 of 15. The arrhythmogenic substrate on the ECS was a focus of automatic tachycardia in 9 of 15 and the slow zone responsible for reentrant arrhythmia in the remaining 6 of 15. Successful elimination of tachycardia without recurrence was obtained in all 15 cases. There was no evidence of valvular damage or disruption of the valvular apparatus. Conclusion: During VT ablation procedures, ECS should be considered for specific mapping and targeted ablation. Once recognized, these structures can be successfully targeted for ablation without valve damage. (J Cardiovasc Electrophysiol, Vol. 21, pp. 245–254, March 2010)  相似文献   

10.
Abstract

Interstitial pneumonitis (IP) associated with polymyositis and dermatomyositis (PM/DM) is a serious complication that affects prognosis. We therefore undertook a retrospective multicenter study to examine the efficacy of a combination treatment with cyclosporin A (CsA) and corticosteroids. Fifty-three IP patients with PM/DM (9 PM, 44 DM) were analyzed. Thirty-two patients treated with CsA plus corticosteroids (9 PM, 23 DM) were included in the study. Four parameters, i.e., subjective symptoms, ausculatory sound, chest radiographs, and respiratory index, were serially evaluated. A general evaluation was performed 4 weeks after the start of the combination treatment. All patients with PM and chronic IP with DM, and 52% of those with acute IP with DM were graded as better than “partially effective” in the general evaluation. In contrast, all patients graded as “progressive” in the general evaluation had acute IP with DM. It is of note that in acute IP with DM, the survival rate of the group primarily treated with CsA and corticosteroids from the early stage of their disease was significantly higher than that of the group initially treated with corticosteroids alone (P = 0.049). In conclusion, a combination treatment of CsA and corticosteroids from the early stage of disease may be advantageous for patients with IP with PM/DM, especially acute IP with DM.  相似文献   

11.
Influenza viruses represent a continuous threat to both animal and human health. The 2009 H1N1 A influenza pandemic highlighted the importance of a swine host in the adaptation of influenza viruses to humans. Nowadays, one of the most extended strategies used to control swine influenza viruses (SIVs) is the trivalent vaccine application, whose formulation contains the most frequently circulating SIV subtypes H1N1, H1N2, and H3N2. These vaccines do not provide full protection against the virus, allowing its replication, evolution, and adaptation. To better understand the main mechanisms that shape viral evolution, here, the SIV intra-host diversity was analyzed in samples collected from both vaccinated and nonvaccinated animals challenged with the H1N1 influenza A virus. Twenty-eight whole SIV genomes were obtained by next-generation sequencing, and differences in nucleotide variants between groups were established. Substitutions were allocated along all influenza genetic segments, while the most relevant nonsynonymous substitutions were allocated in the NS1 protein on samples collected from vaccinated animals, suggesting that SIV is continuously evolving despite vaccine application. Moreover, new viral variants were found in both vaccinated and nonvaccinated pigs, showing relevant substitutions in the HA, NA, and NP proteins, which may increase viral fitness under field conditions.  相似文献   

12.
Japanese rheumatologists consider bucillamine (Buc) to be a useful disease-modifying antirheumatic drug (DMARD) and often give Buc to patients with rheumatoid arthritis (RA) prior to administering methotrexate (MTX). However, no large studies on the efficacy and safety of Buc in RA patients have been published in English to date. We therefore investigated the clinical course of RA patients treated with Buc and compared the results with those for patients treated with MTX to evaluate and confirm the place of Buc in therapeutic strategies for RA in Japan. Our results suggested that Buc should be given to patients with moderately active RA either before or after the administration of MTX because its efficacy can be judged within 3 months and because serious adverse events are rare. Issues like the ability of Buc to prevent joint destruction and its efficacy and safety when combined with agents like etanercept require future study.  相似文献   

13.
BackgroundVideo-assisted thoracoscopic surgery (VATS) has become a standard approach for the treatment of lung cancer. However, its minimally invasive nature limits the field of view and reduces tactile feedback. These limitations make it vital that surgeons thoroughly familiarize themselves with the patient’s anatomy preoperatively. We have developed a virtual reality (VR) surgical navigation system using head-mounted displays (HMD). The aim of this study was to investigate the potential utility of this VR simulation system in both preoperative planning and intraoperative assistance, including support during thoracoscopic sublobar resection.MethodsThree-dimensional (3D) polygon data derived from preoperative computed tomography data was loaded into BananaVision software developed at Colorado State University and displayed on an HMD. An interactive 3D reconstruction image was created, in which all the pulmonary structures could be individually imaged. Preoperative resection simulations were performed with patient-individualized reconstructed 3D images.ResultsThe 3D anatomic structure of pulmonary vessels and a clear vision into the space between the lesion and adjacent tissues were successfully appreciated during preoperative simulation. Surgeons could easily evaluate the real patient’s anatomy in preoperative simulations to improve the accuracy and safety of actual surgery. The VR software and HMD allowed surgeons to visualize and interact with real patient data in true 3D providing a unique perspective.ConclusionsThis initial experience suggests that a VR simulation with HMD facilitated preoperative simulation. Routine imaging modalities combined with VR systems could substantially improve preoperative planning and contribute to the safety and accuracy of anatomic resection.  相似文献   

14.
Treatment of vein graft disease remains a challenge in interventional cardiology because of the risk of embolization and no‐reflow phenomenon. Currently available distal protection devices have their limitations. The PTFE‐covered stents may be well suited for venous graft lesion treatment, but those available commercially to date have poor crossing profiles, and deliverability and high rates of restenosis. We report the first use of over‐and‐under pericardium‐covered stent in combination with drug‐eluting balloon to treat venous graft disease. © 2009 Wiley‐Liss, Inc.  相似文献   

15.
Abstract

Dimethyl trisulfide (DMTS) is a natural organic trisulfide that has been patented as a promising antidotal candidate against cyanide (CN). The primary mode of action of DMTS is as a sulfur donor that enables the conversion of CN to thiocyanate. Recently, it was discovered that DMTS is capable of oxidizing hemoglobin (Hb) to methemoglobin (MetHb) in vitro. The goal of these experiments was to measure the extent of DMTS-induced MetHb formation in vivo. In these experiments, intramuscular (IM) injections of formulated DMTS were administered to mice. Following the IM injection, blood was drawn and analyzed for MetHb using a rapid spectrophotometric method. Methemoglobin levels peaked in a dose-dependent manner between 20 and 30?min., and then began dropping. The highest MetHb levels measured for the 50, 100, 200 and 250?mg/kg doses of DMTS were respectively 3.28, 6.12, 9.69, and 10.76% MetHb. These experiments provide the first experimental evidence that IM administered DMTS generates MetHb in vivo and provide additional evidence for the presence of a secondary therapeutic pathway for DMTS - CN scavenging by DMTS-generated MetHb.  相似文献   

16.
Abstract

Japanese rheumatologists consider bucillamine (Buc) to be a useful disease-modifying antirheumatic drug (DMARD) and often give Buc to patients with rheumatoid arthritis (RA) prior to administering methotrexate (MTX). However, no large studies on the efficacy and safety of Buc in RA patients have been published in English to date. We therefore investigated the clinical course of RA patients treated with Buc and compared the results with those for patients treated with MTX to evaluate and confirm the place of Buc in therapeutic strategies for RA in Japan. Our results suggested that Buc should be given to patients with moderately active RA either before or after the administration of MTX because its efficacy can be judged within 3 months and because serious adverse events are rare. Issues like the ability of Buc to prevent joint destruction and its efficacy and safety when combined with agents like etanercept require future study.  相似文献   

17.

Background and aims

Phenylalanine (Phe) restricted diet, combined with Phe-free l-amino acid supplementation, is the mainstay of treatment for phenylketonuria (PKU). Being the diet a key factor modulating gut microbiota composition, the aim of the present paper was to compare dietary intakes, gut microbiota biodiversity and short chain fatty acids (SCFAs) production in children with PKU, on low-Phe diet, and in children with mild hyperphenylalaninemia (MHP), on unrestricted diet.

Methods and Results

We enrolled 21 PKU and 21 MHP children matched for gender, age and body mass index z-score. Dietary intakes, including glycemic index (GI) and glycemic load (GL), and fecal microbiota analyses, by means of denaturing gradient gel electrophoresis (DGGE) and Real-time PCR were assessed. Fecal SCFAs were quantified by gas chromatographic analysis.

Results

We observed an increased carbohydrate (% of total energy), fiber and vegetables intakes (g/day) in PKU compared with MHP children (p = 0.047), as well a higher daily GI and GL (maximum p < 0.001).Compared with MHP, PKU showed a lower degree of microbial diversity and a decrease in fecal butyrate content (p = 0.02). Accordingly, two of the most abundant butyrate-producing genera, Faecalibacterium spp. and Roseburia spp., were found significantly depleted in PKU children (p = 0.02 and p = 0.03, respectively).

Conclusion

The low-Phe diet, characterized by a higher carbohydrate intake, increases GI and GL, resulting in a different quality of substrates for microbial fermentation. Further analyses, thoroughly evaluating microbial species altered by PKU diet are needed to better investigate gut microbiota in PKU children and to eventually pave the way for pre/probiotic supplementations.  相似文献   

18.
COPD is a progressive illness with worldwide impact. Patients invariably reach a point at which they require palliative interventions. Dyspnea is the most distressing symptom experienced by these patients; when not relieved by traditional COPD management strategies it is termed “refractory dyspnea” and palliative approaches are required. The focus of care shifts from prolonging survival to reducing symptoms, increasing function, and improving quality of life. Numerous pharmacological and non-pharmacological interventions can achieve these goals, though evidence supporting their use is variable. This review provides a summary of the options for the management of refractory dyspnea in COPD, outlining currently available evidence and highlighting areas for further investigation. Topics include oxygen, opioids, psychotropic drugs, inhaled furosemide, Heliox, rehabilitation, nutrition, psychosocial support, breathing techniques, and breathlessness clinics.  相似文献   

19.
脂蛋白(a)与动脉粥样硬化研究进展   总被引:1,自引:0,他引:1  
脂蛋白(a)由低密度脂蛋白和载脂蛋白(a)组成.高血浆脂蛋白(a)水平是动脉粥样硬化和心血管疾病的独立危险因素.脂蛋白(a)不但能参与动脉粥样硬化斑块的形成,还能影响抗炎机制和血管壁中促凝与抗凝因子的平衡.血浆脂蛋白(a)水平的个体差异很大,主要受遗传因素控制.血浆脂蛋白(a)水平对药理和非药理因素都不敏感,临床上缺乏高效安全降低脂蛋白(a)水平的治疗方法.近年,科研工作者发现反义寡核苷酸链和人工合成的肽链等可以降低脂蛋白(a)水平,但用于临床治疗还需进一步研究.本文拟对近年来脂蛋白(a)与动脉粥样硬化研究的新进展进行综述.  相似文献   

20.
In severe illness, profound changes occur in the hypothalamic-pituitary-thyroid axis. The observed decrease in serum concentration of both thyroid hormones and thyrotropin (TSH) are not compatible with a negative feedback loop and suggest a major change in setpoint regulation of the hypothalamic-pituitary-thyroid axis. This is supported by post mortem studies showing a decreased expression of thyrotropin-releasing hormone in the hypothalamic paraventricular nucleus of patients with a decreased serum T3 level. In critical illness, serum T3 may even become undetectable without giving rise to an elevated concentration of serum TSH. It is currently not clearly established whether this reflects an adaptation of the organism to illness or instead a potentially harmful condition leading to hypothyroidism at tissue level. There is thus a need for randomized clinical trials in critically ill patients to investigate whether they may benefit from a normalization of thyroid hormone concentration. Recent clinical studies in these patients involving the administration of hypothalamic peptides open up new ways of achieving this.  相似文献   

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