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71.
The regulation of myelopoiesis was evaluated in B6D2F1 mice inoculated with Friend virus complex (spleen focus-forming virus plus helper virus) or helper virus alone by analyzing acidic isoferritin (AIF) and lactoferrin (LF) interactions with target cells. Under normal conditions, AIF suppresses colony and cluster formation by an Ia- antigen-positive cycling subpopulation of mouse granulocyte-macrophage progenitor cells (CFU-GM). Under the same conditions, the release of AIF-inhibitory activity and granulocyte-macrophage colony stimulatory factors (GM-CSF) from an Ia-antigen-positive subpopulation of monocytes and macrophages is suppressed by LF. Within one to two days after inoculation in vivo with Friend virus complex or helper virus, mouse CFU-GM become insensitive in vitro to suppression by purified human AIF as well as crude mouse AIF, and by four days, bone marrow, spleen, and thymus cells of these mice release much greater quantities of AIF- inhibitory activity than the cells from mice injected with control medium. The Friend virus complex itself has no influence in vitro on CFU-GM from normal mice. In addition, the release of AIF-inhibitory activity from bone marrow, spleen, and resident peritoneal cells and the release of GM-CSF from resident peritoneal cells of mice infected with Friend virus complex are not suppressed by LF. The inability of AIF to suppress colony formation by bone marrow and spleen CFU-GM from mice infected with Friend virus complex is associated with the loss of Ia (I-A subregion) antigens from CFU-GM, even though CFU-GM are in cycle. The nonresponsiveness of bone marrow, spleen, and peritoneal cells from these mice to LF suppression of AIF release and the inability of LF to influence GM-CSF release from peritoneal cells is associated with loss of Ia antigens from these cells. The above abnormalities are similar to the defects noted using cells from patients with leukemia. These results suggest that mice infected with Friend virus complex can serve as a model for investigating abnormalities in cell regulation and their relationships to disease progression. 相似文献
72.
An enzyme-linked immunosorbent assay has been developed for the quantitation of activated Hageman factor-C1 inactivator (HF-C1 INH) complexes. Addition of increasing quantities of either of the major forms of activated Hageman factor (HFa or HFf) to normal plasma or to Hageman factor-deficient plasma leads to a dose-dependent increase in activated HF-C1 INH complexes. As little as 0.5 micrograms/mL of activated HF added to plasma can be detected, corresponding to activation of approximately 2% of plasma HF. The sensitivity of the assay is increased at least tenfold when complexes are formed in HF- deficient plasma, indicating competition between unactivated HF and activated HF-C1 INH complexes for binding to the antibody. Specificity is demonstrated in that addition of activated HF to hereditary angioedema plasma yields less than 1% of the activated HF-C1 INH complex formation obtained with normal plasma. Kaolin activation of HF- deficient plasma yields no detectable complex formation. Kaolin activation of prekallikrein-deficient plasma demonstrates a time- dependent increase in formation of activated HF-C1 INH complex consistent with the ability of HF in this plasma to autoactivate as the time of incubation with the surface is increased. Kaolin treatment of high-molecular weight (HMW) kininogen-deficient plasma yields an even more profound abnormality in the rate of formation of activated HF-C1 INH complexes reflecting the complex role of HMW kininogen in the initiation of contact activation. Although addition of corn inhibitor to plasma prevents activated HF-C1 INH complex formation, it does not inhibit activated HF sufficiently fast to prevent prekallikrein activation. 相似文献
73.
G Llamas Esperón G García Ramos C Gaos J L Jiménéz R Villavicencio L Cueto J Arriaga Gracia 《Archivos del Instituto de Cardiología de México》1985,55(3):247-256
The importance of cardiac autonomic neuropathy (CAN) derives from its remarkable frequency and its clinical impact. The clinical features are postural hypotension and resting tachycardia, these abnormalities may be overlooked in a high number of patients asymptomatic. Although rarely life threatening, CAN causes considerable morbidity, which can be ameliorated by its identification and appropriate treatment. Circulatory reflexes were studied in 48 diabetic patients and 14 normal control subjects. Twenty-six of the diabetic patients had normal response. The remaining 22 had evidence of neuropathy and abnormal cardiac response during these tests. Only one patient had postural syncope but he had severe orthostatic hypotension. The others remained asymptomatic. All the control subjects had normal reflexes. Beat-to-beat variation with deep breathing (sinus arrhythmia), carotid body massage and mental stress, were important for the detection of CAN (86, 90 and 90% sensitivity respectively). The Valsalva maneuver and sinus arrhythmia showed 82 and 92% of specificity for the diagnosis of CAN. Our findings suggest that CAN in diabetic patients can be detected by these relatively simple test. We propose a rational approach to the diagnosis. Our method is applicable as a clinical routine examination for cardiac neuropathy. 相似文献
74.
OBJECTIVES: Vascular anomalies in the urogenital tract are very rare and those located in glans penis are the most uncommon. There is some controversy concerning their nomenclature, diagnosis and treatment. We present an analysis of our experience and a critical review of the literature. METHODS: Three cases of vascular lesions in the glans penis concordant with venous malformations were diagnosed at our center in 1996. The patients were 22, 20, and 12 years old, and attended our center for aesthetic reasons only. Even though two of the lesions were large, treatment with neodymium:yttrium-aluminium-garnet (Nd:YAG) laser irradiation was used. RESULTS: The outcome of treatment was satisfactory and no signs of recurrence were observed at follow-up examinations after a minimum of 18 months. CONCLUSIONS: Until recently, surgery has been the classical therapeutic approach, and only a few cases treated with the Nd:YAG laser have been reported. However, in our opinion, this should be the first choice treatment for this anomaly, given its efficacy, cosmetic results, and low morbidity. 相似文献
75.
AP Monaco JF Burke RM Ferguson PF Halloran BD Kahan JA Light AJ Matas K Solez 《American journal of kidney diseases》1999,33(1):150-160
Chronic rejection accounts for most renal allograft losses after the first year posttransplantation. On March 24 and 25, 1997, a roundtable of five transplant surgeons, two nephrologists, and one pathologist assembled in Dallas, Texas, to review critical issues surrounding chronic renal allograft rejection. This article summarizes the presentations and relevant discussions of this meeting regarding the cause of chronic rejection, clinical diagnoses, risk factors, future prospects for intervention strategies, and general recommendations for the transplant community. Growing evidence indicates that chronic rejection is the aggregate sum of irreversible immunologic and nonimmunologic injuries to the renal graft over time. A history of acute rejection episodes and inadequate immunosuppression, likely attributable to inconsistent cyclosporine exposure or poor patient compliance, are among the most recognizable immunologic risk factors for chronic rejection. Donor organ quality, delayed graft function, and other donor and recipient variables leading to reduced nephron mass are nonimmunologic factors that contribute to the progressive deterioration of renal graft function. Clinical management of renal transplant recipients should incorporate both immunologic- and nonimmunologic-based intervention strategies aimed at minimizing risk factors to thwart the progression of chronic rejection and improve long-term allograft and patient survival. 相似文献
76.
LM Paes da Silva Ramos Fernandes R Ordinola-Zapata MA Húngaro Duarte AL Alvares Capelozza 《Dento maxillo facial radiology》2013,42(1):80179163
Objectives
The aim of this study was to determine the prevalence of apical periodontitis (AP) detected in cone beam CT (CBCT) images from a database.Methods
CBCT images of 300 Brazilian patients were assessed. AP images were measured in three dimensions. Age, gender, number and location of total teeth in each patient were considered. AP location was considered according to tooth groups. The extent of AP was determined by the largest diameter in any of the three dimensions. Percentages and the χ2 test were used for statistical analysis.Results
AP was found in 51.4% of the patients and in 3.4% of the teeth. Higher prevalence of AP was found in 60- to 69-year-olds (73.1%) and in mandibular molars (5.9%) (p < 0.05). Inadequate endodontic treatment presented higher prevalence of AP (78.1%).Conclusions
AP can be frequently found in CBCT examinations. The presence of AP has a significant association with patients'' age, and tooth type and condition. CBCT databases are useful for cross-sectional studies about AP prevalence in a population. 相似文献77.
78.
D Bickham P Le Rossignol C Gibbons AP Russell 《Journal of Science and Medicine in Sport》2002,5(4):372-382
The purpose of this study was to re-assess the accumulated oxygen deficit (AOD), incorporating recent methodological improvements i.e., 4 min submaximal tests spread above and below the lactate threshold (LT). We Investigated the Influence of the VO2 -speed regression, on the precision of the estimated total energy demand and AOD. utilising different numbers of regression points and including measurement errors. Seven trained middle-distance runners (mean +/- SD age: 25.3 +/- 5.4y, mass: 73.7 +/- 4.3kg. VO2max 64.4 +/- 6.1 mL x kg(-1) x min(-1)) completed a VO2max, LT, 10 x 4 min exercise tests (above and below LT) and high-intensity exhaustive tests. The VO2 -speed regression was developed using 10 submaximal points and a forced y-intercept value. The average precision (measured as the width of 95% confidence Interval) for the estimated total energy demand using this regression was 7.8mL O2 Eq x kg(-1) x min(-1). There was a two-fold decrease in precision of estimated total energy demand with the Inclusion of measurement errors from the metabolic system. The mean AOD value was 43.3 mL O2 Eq x kg(-1) (upper and lower 95% CI 32.1 and 54.5mL o2 Eq x kg(-1) respectively). Converting the 95% CI for estimated total energy demand to AOD or including maximum possible measurement errors amplified the error associated with the estimated total energy demand. No significant difference in AOD variables were found, using 10,4 or 2 regression points with a forced y-intercept. For practical purposes we recommend the use of 4 submaximal values with a y-intercept. Using 95% CIs and calculating error highlighted possible error in estimating AOD. Without accurate data collection, increased variability could decrease the accuracy of the AOD as shown by a 95% CI of the AOD. 相似文献
79.
Gonçalves PD Srougi M Dall'lio MF Leite KR Ortiz V Hering F 《The Journal of urology》2004,172(2):470-474
PURPOSE: Renal cell carcinoma is a tumor with unpredictable behavior and defining reliable prognostic factors would be extremely valuable in the clinical setting. Tumor stage, nuclear grade and tumor cell type are the main prognostic clinical parameters available. In this study we evaluated the role of microvascular involvement in the primary lesion for predicting tumor behavior in patients with low stage clinical disease. MATERIALS AND METHODS: A total of 95 patients with clinically localized renal cell carcinoma (stages T1-T2 Nx M0) underwent radical nephrectomy and/or nephron sparing surgery, and were followed for a median of 45 months. The impact of microvascular tumor invasion on disease progression and its correlation with known pathological outcomes (tumor size, nuclear grade and cell type) were studied. RESULTS: Microvascular tumor invasion was observed in 24 patients (25%), of whom 50% had disease recurrence. Of the 71 patients without microvascular invasion only 4 (6%) showed tumor recurrence. When microvascular invasion was correlated with other histological parameters, a significant statistical association was noted with tumor diameter, perirenal fat invasion, macroscopic extension to the renal vein, nuclear grade, lymph node metastasis and sarcomatous elements in the tumor. Multivariate analysis showed that microvascular invasion and the involvement of regional lymph nodes were independent predictors of disease recurrence. Concerning cancer specific survival, microvascular invasion and perirenal fat infiltration were the only factors related to death. CONCLUSIONS: Microvascular invasion is an independent and relevant clinical prognostic parameter for low clinical stage renal cell carcinoma. 相似文献
80.
L Lladó J Fabregat C Baliellas A Gonzalez-Castillo E Ramos E Gonzalez-Vilatarsana J Torras A Rafecas 《Transplantation proceedings》2012,44(6):1557-1559