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Complex karyotype (CK) on metaphase cytogenetics discriminates poor outcome in chronic lymphocytic leukaemia (CLL) patients undergoing salvage treatment; we hypothesized that it might provide prognostic information for patients undergoing allogeneic stem cell transplant. Fifty‐one CLL patients were analysed following transplant; 18‐month overall survival (OS), event‐free survival (EFS) and cumulative incidence of progression estimates were 35%, 14% and 63%, respectively, in patients with CK (n = 19) versus 83%, 68% and 29% in patients without (n = 32) (≤ 0·0001, ≤ 0·0001, and P = 0·02). In patients with high‐risk interphase cytogenetics, CK remained predictive of worse OS (P = 0·02) and EFS (P = 0·009). These findings support further evaluation of metaphase karyotype in transplant risk assessment.  相似文献   
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Human and rhesus monkey platelets secrete at least two antiheparin proteins: platelet factor 4 (PF4) and low affinity platelet factor 4 (LA-PF4). Neither of these proteins showed species-related antigenic differences. As determined by radioimmunoassay, the levels of PF4 and LA-PF4 antigen per 10(9) monkey platelets amounted to 10.7 and 20.3 microgram, respectively. One milliliter of monkey plasma prepared from blood collected into an anticoagulant composed of EDTA, prostaglandin E1, and theophylline solution contained 22.4 ng LA-PF4 and 8.0 ng PF4. Concentrations of these two platelet-specific proteins in monkeys closely resembled levels found in human platelets and plasma. Infusion of prostacyclin (PGI2) (100 or 300 ng/kg/min) into monkeys for 15 min resulted in a significant decrease of plasma levels of LA-PF4 antigen and of PF4 by 40%--60% (p < 0.0001). This decrease was related to the inhibitory effect of PGI2 on the secretion of platelets stimulated by a catheter or by venipuncture. Longer infusion of PGI2 did not produce further significant change. The supernate obtained after aggregation of human platelets stimulated by thrombin was injected into monkeys receiving PGI2 infusion. The disappearance of LA-PF4 antigen in monkey plasma followed a biphasic exponential curve with half-lives for the fast and slow components of 8.4 and 63 min. PF4 disappeared faster but followed the same pattern (half-lives for the fast and slow component of 2.1 and 70 min). Analysis of the experimental data suggests that the low levels of secreted platelet proteins in monkey plasma are related to their minimal in vivo release and to their rapid clearance.  相似文献   
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The ascending thalamofugal visual pathway in pigeons (Columba livia) terminates in the telencephalic wulst. Characterizing the role of this pathway in visually guided behaviour has remained a challenge. To determine whether this pathway, and in particular the wulst, may participate in sun-compass-guided behaviour in homing pigeons, intact, ectostriatum-lesioned or wulst-lesioned pigeons were trained to use their sun compass to locate the direction of a food reward in an outdoor, octagonal arena. Control and ectostriatum-lesioned pigeons learned the task well, and orientated appropriately during the first trial of the last three training sessions and after a phase-shift manipulation. In contrast, the wulst-lesioned pigeons learned the task but they took more sessions to learn, and their directional choices were more scattered during the first trial of the last three training sessions and after the phase-shift manipulation. A subsequent regression analysis indicated that deeper layers of the wulst might have made more of a contribution to the observed behavioural impairments. The data indicate that the homing pigeon wulst participates in visually guided behaviour when the sun compass is used to learn the directional location of a goal.  相似文献   
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Electrophysiological activity was recorded from single neurons (units) in the hippocampal formation (HF) of freely moving homing pigeons in order to provide a taxonomy of unit types found in the avian HF; a taxonomy that could be used to define regional subdivisions and be compared with unit types found in the mammalian hippocampus. Two distinct types of unit were observed in the avian HF. One type was uniformly characterized by relatively rapid firing rates and shorter spike widths, and was found throughout the HF. The other type was more variable in activity profile but, compared with the fast-firing units, was characterized by slower firing rates and longer spike widths. However, despite the variable nature of the slow-firing units, most slow-firing units recorded within a given anatomical region displayed similar firing rates, spike widths, and interspike intervals. In general, ventral HF units displayed activity patterns similar to projection cells found in the mammalian Ammon's horn. Most dorsocaudal units displayed activity patterns similar to presumed granular cells in the mammalian dentate gyrus. By contrast, most dorsorostral units displayed activity patterns similar to a type of unit found in the mammalian subiculum. Although different in some details, the overall activity profile of units found in the avian HF, and their regional distribution, is strikingly similar to unit types found in the mammalian hippocampus, suggesting that unit activity profile is one hippocampal dimension conserved through evolution.  相似文献   
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Background

India accounts for approximately 10 million orthopaedically handicapped children and adults with limb deformity. Ilizarov ring fixator could treat most of these deformities.

Methods

Twenty cases of deformities of lower limb managed with Ilizarov technique during period between March 2001 and February 2003 were studied.

Results

55% were in the age group of 11-30 years. Out of the 20 cases studied, 6 were congenital talipes equino varus, 8 were fixed flexion deformity of knee, 4 were equines deformity of the ankle and 2 were malunited fracture shaft of tibia.4 patients who had recurrence were operated for fixed flexion deformity of the knee. The main complication encountered was pin tract infection, which was seen in 15(75%) cases. In 16(80%) cases, the results were excellent with no recurrence of deformity and patients were able to walk independently. In 4 (20%) cases, recurrence was mild to moderate (10 to 20) but all of them were able to ambulate idependently and carry out their routine activities.

Conclusion

Ilizarov ring fixator is a superior compared to conventional methods for correction of deformities of lower limb.Key Words: Ilizarov method, Ligamentotaxis, Distraction  相似文献   
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Background

The present study was conducted to study the efficacy and toxicity profile of methotrexate chloroquine combination in treatment of active rheumatoid arthritis.

Methods

24 patients of rheumatoid arthritis confirming to revised American Rheumatism Association (ARA) criteria were studied prospectively for twenty months. Clinical evaluation was made every 3 months. Clinical disease variables measured at each visit were number of joints with swelling, number of joints with tenderness and pain, duration of morning stiffness and physician and patient assessment of disease activity. Blood counts, liver function tests and other adverse effects due to drugs were monitored every 2 months.

Results

10 patients demonstrated more than 50% improvement. 4 patients withdrew from study, 2 because of excessive nausea and vomiting and 2 because of noncompliance. Other side effects noted were hyperpigmentation, photosensitivity, skin rashes, raised transaminases and stomatitis.

Conclusion

Methotrexate chloroquine combination has good efficacy and toxicity profile. Gastrointestinal side effects are most common and usually responsible for the discontinuation of the drugs.Key Words: Rheumatoid arthritis, Methotrexate, Chloroquine, Efficacy, Toxicity  相似文献   
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