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641.
Flow immunophenotyping, DNA content analysis, and polymerase chain reaction (PCR) amplification for t(11;14) and t(14;18) were performed on 11 cases of typical mantle cell lymphoma (MCL), 5 cases of apparent MCL with proliferation centers (MCL-PC), and 5 cases of small lymphocytic lymphoma (SLL). Immunophenotyping showed IgM (P < .001), Ig light (P < .001), and CD20 (P < .001) expression to be more intense in MCL than in SLL. In MCL-PC, the mean intensity of IgM, Ig light chain, and CD20 expression was intermediate to the intensities observed in MCL and SLL. Furthermore, in contrast to SLL, all MCL and 4 of 5 MCL-PC cases exhibited stronger CD20 than CD19 expression. CD10 expression was not observed in any case and CD5 expression was present in all SLL and MCL-PC cases and in 9 of 11 MCL cases. DNA content analysis showed an S- phase fraction of less than 3% in all cases studied and, except for 1 MCL case, all lymphomas were DNA diploid. The t(11;14) breakpoint junctions involving the bcl-1 major translocation cluster were amplified by PCR in 4 of 11 (36%) MCL cases and in none of the MCL-PC or SLL cases. The t(14;18) involving the bcl-2 major breakpoint region was not identified by PCR in any case. We conclude that the level of expression of surface antigens and the rapid detection of t(11;14) by PCR are potentially useful for distinguishing MCL and SLL in the clinical setting. Further investigations as to the biologic relationship between MCL, MCL-PC, and SLL, and the utility of t(11;14) PCR in these lymphomas are warranted.  相似文献   
642.
One hundred and sixty eight adult patients with B-cell non-Hodgkin's lymphoma (NHL) and other hematologic malignancies who underwent autologous or allogeneic bone marrow transplantation (BMT) were investigated for the subsequent development of hemolytic-uremic syndrome (HUS). All patients were conditioned with cyclophosphamide and total body irradiation. When examined at 3-month intervals for the first year post-BMT, all patients had uniform measurements of hematocrit (Hct) and serum creatinine. Sixteen patients who initially exhibited Hct and creatinine values that were normal range for the BMT populations developed a sudden decrease in Hct and increase in creatinine between 3 and 11 months post-BMT and fulfilled the clinical and laboratory criteria for HUS. None of these patients had known active cytomegalovirus infection, graft-versus-host disease, or cyclosporine administration. The degree of decrease in Hct and creatinine elevation ranged from solely laboratory abnormalities to a clinically significant syndrome. Twelve of the 16 patients developed acute clinical complications of congestive heart failure, hypertension (HTN), or peripheral edema. Twelve patients required red blood cell support, whereas only four patients required platelet transfusions. Both hemolytic anemia and thrombocytopenia have resolved in virtually all cases. At a mean follow up of 18 months postdiagnosis, creatinine elevations have persisted along with HTN. All patients have survived without life-threatening long-term sequelae. With the increasing use of BMT as a curative modality for patients with hematologic malignancies, it becomes important to prospectively monitor patients for the development of HUS and its potential long-term impact on renal function.  相似文献   
643.

Introduction

The surgical Apgar score (SAS) can predict 30-day major complications or death after surgery. Studies have validated the score in different patient populations and suggest it should be used to objectively guide postoperative care. We aimed to see whether using the SAS in a decisive approach in a future randomised controlled trial (RCT) would be likely to demonstrate an effect on postoperative care and clinical outcome.

Methods

A total of 143 adults undergoing general/vascular surgery in 9 National Health Service hospitals were recruited to a pilot single blinded RCT and the data for 139 of these were analysed. Participants were randomised to a control group with standard postoperative care or to an intervention group with care influenced (but not mandated) by the SAS (decisive approach). The notional primary outcome was 30-day major complications or death.

Results

Incidence of major complications was similar in both groups (control: 20/69 [29%], intervention: 23/70 [33%], p=0.622). Immediate admissions to the critical care unit was higher in the intervention group, especially in the SAS 0–4 subgroup (4/6 vs 2/7) although this was not statistically significant (p=0.310). Validity was also confirmed in area under the curve (AUC) analysis (AUC: 0.77).

Conclusions

This pilot study found that a future RCT to investigate the effect of using the SAS in a decisive approach may demonstrate a difference in postoperative care. However, significant changes to the design are needed if differences in clinical outcome are to be achieved reliably. These would include a wider array of postoperative interventions implemented using a quality improvement approach in a stepped wedge cluster design with blinded collection of outcome data.  相似文献   
644.

Background

Serum creatinine is not a sensitive marker to assess early loss of renal function in acute kidney injury. Timed creatinine clearance and several formula used to predict glomreular filtration rate have not been validated.

Methods

In a prospective observational study in 50 adult patients admitted to the intensive care unit with apparent normal renal function, we assessed the glomerular filtration rate by the formula methods and timed creatinine clearance.

Result

The mean serum creatinine was 0.77mg/dl, SD ± 0.15 (range 0.5-1.14 mg/dl). The mean measured creatinine clearance was 87.15 ml/min/1.73m2, SD ± 20.5 (range 56.9-137 ml/min/1.73m2). In 25 (50%) patients, one hour urinary creatinine clearance was <80 ml/min/1.73m2 and in two (4%) patients, the creatinine clearance was <60 ml/min/1.73m2. Spearman correlation coefficient and regression analysis revealed a statistically significant correlation for the Cockcroft-Gault and predictive equations when compared with measured creatinine clearance. The differences between the predictive equations and creatinine clearance, as illustrated by the ±95% confidence interval in the Bland-Altman graphs was very significant [Cockcroft- Gault = −40.3 to 17.7 ml/min/ 1.73m2, Modification of Diet in Renal Disease equation = −46.2 to 30.6 ml/min/1.73m2 and the simplified Modification of Diet in Renal Disease equation = −72.8 to 24.8 ml/min/1.73m2].

Conclusion

Formula methods and creatinine clearance are more sensitive than serum creatinine in detecting early phase of acute kidney injury. However, there is no agreement between these methods of glomerular filtration rate estimation.Key Words: Acute kidney failure, Glomerular filtration rate  相似文献   
645.
646.
647.
Male andropause, male climacteric or viropause is a condition in which men suffer from complex symptomatology due to low androgen level with aging. After the age of 40 years testosterone level starts declining and andropause corresponds to the age at which a pathogenic threshold is reached. This review summarizes the etiology, consequences, screening, diagnosis, monitoring of androgen deficiency in aging male (ADAM). The pros and cons of testosterone replacement therapy (TRT) in elderly male have been discussed. Currently oral, transdermal, transbuccal, intramuscular, and subcutaneous implants are available for clinical use. The choice is made by physicians based on therapeutic indication and patient preferences.Key Words: Andropause, Aging male, Testosterone replacement therapy  相似文献   
648.
Steinberg  HN; Tsiftsoglou  AS; Robinson  SH 《Blood》1985,65(1):100-106
The human leukemic cell lines K562 and HL-60 were cocultured with normal bone marrow (BM) cells. Coculture with 10(4) K562 or HL-60 cells results in 50% inhibition of normal CFU-E and BFU-E colony formation. However, when the same number of K562 and HL-60 cells is first treated for two to five days with agents that induce their differentiation, a gradual loss in their capacity to inhibit CFU-E and BFU-E colony formation is observed. The inhibitory material in K562 cells is soluble and present in conditioned medium from cultures of these cells. The degree to which leukemic cell suppression of CFU-E and BFU-E growth is reversed is correlated with the time of exposure to the inducing agent. Suppression is no longer evident after five days of prior treatment with inducers. In fact, up to a 90% stimulation of CFU-E growth is observed in cocultures with K562 cells that have been pretreated with 30 to 70 mumol/L hemin for five days. K562 cells treated with concentrations of hemin as low as 30 mumol/L demonstrate increased hemoglobin synthesis and grow normally, but no longer have an inhibitory effect on CFU-E growth. Hence, reversal of normal BM growth inhibition must be caused by the more differentiated state of the K562 cells and not by a decrease in the number of these cells with treatment. Thus, induction of differentiation in cultured leukemic cells not only alters the malignant cell phenotype but also permits improved growth of accompanying normal marrow progenitor cells. Both are desired effects of chemotherapy.  相似文献   
649.
We compared the properties of plasma von Willebrand factor (vWF) from normal individuals and from two patients with type IIA (Glu875Lys) and type IIB (duplication of Met 540) von Willebrand disease (vWD) with the corresponding fully multimerized recombinant proteins. We included cryosupernatant from normal human plasma and type IIA plasma (Cys509Arg). Functions of vWF were analyzed by binding assays to platelets in the presence of ristocetin or botrocetin. Parameters of binding (number of binding sites per vWF subunit, and dissociation constant Kd) were quantitatively estimated from the binding isotherms of 125I-botrocetin or glycocalicin to vWF, independently of the size of the multimers. We found that ristocetin- or botrocetin-induced binding to platelets was correlated in all cases with the size of vWF multimers. In the absence of inducer, only type IIB rvWF Met-Met540 spontaneously bound to platelets. No significant difference of binding of purified botrocetin to vWF was found between normal and patients' plasma, or between wild-type rvWF (rvWF-WT) and rvWF-Lys875. In contrast, affinity of botrocetin for type IIB rvWF Met-Met540 was decreased. Botrocetin-induced binding of glycocalicin to vWF from all plasma and cryosupernatant was similar. Compared with rvWF-WT, binding of glycocalicin to rvWF-Lys875 was normal. In contrast, the affinity for type IIB rvWF Met-Met540 was 10-fold greater. Thus, our data suggest that, in the patients tested, the abnormal IIA phenotype results from the lack of large-sized multimers and is independent of the point mutations. In contrast, the type IIB mutation is directly involved by providing a conformation to the vWF subunits that allows the high molecular weight multimers to spontaneously interact with platelet glycoprotein Ib.  相似文献   
650.
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