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61.
Busulfan and cyclophosphamide (BuCy) are currently the most widely used myeloablative regimen to treat malignancies with allogeneic stem cell transplantation. Fludarabine has considerable efficacy in both immunosuppression and tumor cells killing with a minimal extramedullary toxicity. We evaluated the efficacy of 40 mg/m(2) fludarabine i.v. for 5 days and busulfan 4 mg/kg/day p.o. for 4 days as myeloablative conditioning regimen in 70 patients (median age 24 years) with acute leukemia or chronic phase of myelogenous leukemia. They all had human leukocyte antigen-matched sibling donors. The patients received 10 mug/kg granulocyte colony stimulating factor (GCSF), 24 h after stem cell infusion until engraftment occurred. Graft-versus-host disease (GVHD) prophylaxis included 3 mg/kg cyclosporine-A i.v. from day -2 to +6 followed by 12 mg/kg p.o. until day +60. The median time of neutrophil recovery (>0.5 x 109/l) and platelet recovery (>20 x 109/l) were 10 and 12 days, respectively. Mucositis (93%) and hepatic toxicity (16%) resolved with conservative therapy. The incidence of acute GVHD grade I-II and III-IV were 38.6 and 15.7% respectively. Overall survival and disease-free survival were 71 and 64% respectively with 17 months median follow-up for surviving patients. We conclude that FluBu may be used as a substitute for BuCy with almost the same efficacy and with a lower transplant adverse effect but to increase anti-leukemic effects, especially in acute lymphoblastic leukemia patients, it needs some modifications.  相似文献   
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Introduction: Intestinal parasitic infections (IPIs) are important causes of morbidity and mortality in patients with immunocompromising conditions.

Objective: The aim of this study was to determine the prevalence of IPIs in different groups of immunocompromised patients, including hemodialysis patients (HD), renal transplant recipients (RTR), cancer and HIV/AIDS patients in comparison with healthy individuals in two central cities of Iran (Kashan and Qom).

Methods: In this case–control study, the stool samples of 135?HD, 50 RTR, 60 cancer patients, 20 HIV/AIDS patients and 120 healthy subjects were tested using direct-smear, formol-ether concentration, Ziehl–Neelsen staining and Agar plate method.

Results: The overall infection rate was 11.7% (31/265) in patient groups and 0% (0/120) in the control group. The frequency of parasites was 25% in HIV/AIDS patients, 11.9% (16/135) in HD, 12.0% (6/50) in RTR and 6.7% (4/60) in cancer patients. Blastocystis hominis (4.2%) and Giardia lamblia (3.0%) were the most prevalent parasites in patient groups. The infection rate was significantly higher in male (17.6%) than female (5.4%) patients (p?=?.002), but no statistically significant association was observed according to the age and educational levels.

Conclusions: This study showed a high prevalence of IPIs in immunocompromised patients. The results of this study suggest that periodic stool examinations for screening of IPIs should be included as a part of routine medical care in these patients.  相似文献   
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Objectives: We studied the association between the prooxidant-antioxidant balance (PAB), anti-malondialdehyde-modified low-density lipoprotein (oxidized LDL, ox-LDL) IgG antibody and indices of cardiac function (systolic and diastolic function) in patients with coronary artery disease (CAD). Methods: Fifty-five patients with established CAD were selected, and serum levels of anti-ox-LDL IgG and PAB values were measured and compared with 40 matched healthy controls. Systolic and diastolic functions were determined for all patients. Results: PAB values were significantly higher in patients than in controls (p < 0.001), whilst serum anti-ox-LDL concentrations were not statistically different between the 2 groups (p = 0.821). However, after adjustment for high-density lipoprotein cholesterol, the patients had higher anti-ox-LDL levels (p = 0.04). Total PAB values were inversely associated with ejection fraction (r = -0.326, p = 0.031), but this was not the case for anti-ox-LDL in either group (p > 0.05). Conclusion: Serum concentrations of a marker of oxidative stress (PAB values) are inversely associated with cardiac function. PAB is a relatively simple index that could be incorporated into risk assessment in CAD patients. Anti-ox-LDL IgG antibody concentration does not appear to reflect total oxidative stress as assessed by PAB.  相似文献   
65.
Background: Natural killer (NK) cells are the effector cells of innate immunity that respond to infection and tumor. Interactions between killer cell immunoglobulin like receptors (KIR) and human leukocyte antigen (HLA) class I molecules regulate NK cells responses to eliminate infected and transformed cells. Objective: To investigate the impact of KIR genes, HLA ligand genes, and KIR-HLA combinations on susceptibility to tuberculosis (TB) in Lur population of Iran. Methods: The genomic DNA of 50 patients with TB from Lorestan province of Iran was genotyped for sixteen KIR genes and their five major HLA class I ligands were determined by a polymerase chain reaction-sequence-specific primers (PCR-SSP) assay. The results were compared with those of 200 healthy unrelated Iranian individuals. Results: In Lur population of Iran, a significant decrease in frequency of KIR3DS1 was found in TB patients compared to control group (24% vs. 44.5%, OR=0.394, CI=0.194-0.798, p=0.013). Also, among the three activating genes that may use HLA class I molecules as their ligands, a significant decrease was shown in frequency of KIR3DS1 with HLA-B Bw4Ile80 ligand in TB patients compared to control group (4% vs. 23%, OR=0.14, CI=0.033-0.596, p=0.004). Conclusion: These findings imply a genetic imbalance between activating and inhibitory KIR genes and KIR-HLA combinations in Lur TB patients. Low level of activating KIR3DS1 and its combination with HLA-B Bw4Ile80 ligand might have an influence on the susceptibility to TB in Lur population of Iran.  相似文献   
66.
The mathematical theory of compressed sensing (CS) asserts that one can acquire signals from measurements whose rate is much lower than the total bandwidth. Whereas the CS theory is now well developed, challenges concerning hardware implementations of CS-based acquisition devices--especially in optics--have only started being addressed. This paper presents an implementation of compressive sensing in fluorescence microscopy and its applications to biomedical imaging. Our CS microscope combines a dynamic structured wide-field illumination and a fast and sensitive single-point fluorescence detection to enable reconstructions of images of fluorescent beads, cells, and tissues with undersampling ratios (between the number of pixels and number of measurements) up to 32. We further demonstrate a hyperspectral mode and record images with 128 spectral channels and undersampling ratios up to 64, illustrating the potential benefits of CS acquisition for higher-dimensional signals, which typically exhibits extreme redundancy. Altogether, our results emphasize the interest of CS schemes for acquisition at a significantly reduced rate and point to some remaining challenges for CS fluorescence microscopy.  相似文献   
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The effects of external resistance on the recruitment of trunk muscles and the role of intrinsic and reflexive mechanisms to ensure the spinal stability are significant issues in spinal biomechanics. A computational model of spine under the control of 48 anatomically oriented muscle actions was used to simulate iso-resistive trunk movements. Neural excitation of muscles was attained based on inverse dynamics approach along with the stability-based optimization. The effect of muscle spindle reflex response on the trunk movement stability was evaluated upon the application of a perturbation moment. In this study, the trunk extension movement at various resistance levels while extending from 60 degrees flexion to the upright posture was investigated. Incorporation of the stability condition as an additional constraint in the optimization algorithm increased antagonistic activities for all resistance levels demonstrating that the co-activation caused an increase in the intrinsic stiffness of the spine and its stability in a feed-forward manner. During the acceleration phase of the movement, extensors activity increased while flexors activity decreased in response to the higher resistance. The co-activation ratio noticed in the braking phase of the movement increased with higher resistance. In presence of a 30 Nm flexion perturbation moment, reflexive feed-back noticeably decreased the induced deviation of the velocity and position profiles from the desired ones at all resistance levels. The stability-generated co-activation decreased the reflexive response of muscle spindles to the perturbation demonstrating that both intrinsic and reflexive mechanisms contribute to the trunk stability. The rise in muscle co-activation can ameliorate the corruption of afferent neural sensory system at the expense of higher loading of the spine.  相似文献   
70.
INTRODUCTION: While the undisplaced acetabular fractures have a good prognosis after conservative treatment, the management of the displaced fractures has been a controversial issue over the last decades with variable results in their treatment and prognosis. Anatomical reduction can be only achieved operatively. The long term outcome of 209 patients with displaced acetabular fractures treated by open reduction and internal fixation was presented. MATERIAL AND METHODS: Between 1972 and 1996, 209 patients with a mean age of 38 years (15-62a) were treated for displaced acetabular fractures operatively. 161 patients could be followed up over a period of 2 to 20 years. The function of the hip joint in correlation with radiological results was evaluated according to the scheme of Merle d'Aubinge. RESULTS: Patients with single column fractures showed 90% good or excellent results followed by 55% good or excellent results in patients with transverse fractures. The highest rates of complication (20% osteoarthritis, 6% femoral head necrosis, 9% heterotopic ossification) were observed in both column fractures and in transverse and posterior wall fractures. Deep infection was observed in 6 cases (4%), superficial wound infection in 8 cases (5%). Primary sciatic nerve palsy was seen in 10 cases (6%) and postoperative peroneal nerve palsy in 6 cases (4%), all of which improved during the rehabilitation period. CONCLUSION: Displaced acetabular fractures of the weight bearing part of the dome, i.e. transtectal fractures, should be treated operatively. The operation should preferably be performed within one week after the injury.  相似文献   
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