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121.
Dercksen MW; Weimar IS; Richel DJ; Breton-Gorius J; Vainchenker W; Slaper- Cortenbach CM; Pinedo HM; von dem Borne AE; Gerritsen WR; van der Schoot CE 《Blood》1995,86(10):3771-3782
In the present study, we show by adhesion assays and ultrastructural studies that platelets can bind to CD34+ cells from human blood and bone marrow and that this interaction interferes with the accurate detection of endogenously expressed platelet glycoproteins (GPs). The interaction between these cells was found to be reversible, dependent on divalent cations, and mediated by P-selectin. Enzymatic characterization showed the involvement of sialic acid residues, protein(s). The demonstration of mRNA for the P-selectin glycoprotein ligand 1 (PSGL-1) in the CD34+ cells by polymerase chain reaction (PCR) analysis suggests that this molecule is present in these cells. Under conditions that prevent platelet adhesion, a small but distinct subpopulation of CD34+ cells diffusely expressed the platelet GPIIb/IIIa complex. These cells were visualized by immunochemical studies. Furthermore, synthesis of mRNA for GPIIb and GPIIIa by CD34+ cells was shown using PCR analysis. The semiquantitative PCR results show relatively higher amounts of GPIIb mRNA than of PF4 mRNA in CD34+CD41+ cells in comparison with this ratio in platelets. This finding is a strong indication that the PCR results are not caused by contaminating adhering platelets. MoAbs against GPIa GPIb alpha, GPV, P- selectin, and the alpha-chain of the vitronectin receptor did not react with CD34+ cells. The number of CD34+ cells expressing GPIIb/IIIa present in peripheral blood stem cell (PBSC) transplants was determined and was correlated with platelet recovery after intensive chemotherapy in 27 patients. The number of CD34+CD41+ cells correlated significantly better with the time of platelet recovery after PBSC transplantation (r = .83, P = .04) than did the total number of CD34+ cells (r = .55). Statistical analysis produced a threshold value for rapid platelet recovery of 0.34 x 10(6) CD34+CD41+ cells/kg. This study suggests that if performed in the presence of EDTA the flow cytometric measurement of GPIIb/IIIa on CD34+ cells provides the most accurate indication of the platelet reconstitutive capacity of the PBSC transplant. 相似文献
122.
Weisdorf DJ; Verfaillie CM; Davies SM; Filipovich AH; Wagner JE Jr; Miller JS; Burroughs J; Ramsay NK; Kersey JH; McGlave PB 《Blood》1995,85(12):3452-3456
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
123.
124.
125.
Comparison of FEV1 reference equations for evaluating a cystic fibrosis therapeutic intervention 下载免费PDF全文
126.
Pulmonary vein stenosis with collateralization via esophageal varices: Long‐term follow‐up after successful treatment with drug‐eluting stent 下载免费PDF全文
Jason F. Goldberg MD Craig L. Jensen MD Rajesh Krishnamurthy MD Nidhy P. Varghese MD Henri Justino MD CM FRCPC FSCAI 《Congenital heart disease》2018,13(1):124-130
Objective
We describe the long‐term follow‐up of a child with recurrent hemoptysis due to severe pulmonary vein stenosis decompressing via collaterals to esophageal varices.Design
Case reportSetting
Tertiary children's hospitalPatient
Single child through ages 2‐ to 11‐year oldInterventions
The child underwent cutting balloon angioplasty, bare metal stenting, and implantation of a PTFE‐covered stent, all of which failed rapidly. Only after placement of a paclitaxel drug eluting stent did he have prolonged relief from hemoptysis and long‐term patency of the treated vein. The stents were serially dilated to keep up with somatic growth of the child, eventually culminating in the need to induce intentional stent fracture.Conclusions
We highlight novel transcatheter techniques to treat this vexing condition, discuss mechanisms of disease treatment and progression, and present the only patient with this rare combination of lesions to have achieved both longstanding pulmonary vein patency and resolution of esophageal varices. 相似文献127.
Two‐year trial of intermittent insulin therapy vs metformin for the preservation of β‐cell function after initial short‐term intensive insulin induction in early type 2 diabetes 下载免费PDF全文
128.
Chalmers RM; Howard RS; Wiles CM; Hirsch NP; Miller DH; Williams A; Spencer GT 《QJM : monthly journal of the Association of Physicians》1996,89(6):469-476
Twenty-nine patients with a neuronopathic or neuropathic disorder were
referred for assessment of respiratory insufficiency between 1978 and 1994.
Diagnoses included spinal muscular atrophy (6), chronic idiopathic
demyelinating neuropathy (4), Vialetto-van Laere syndrome (3), hereditary
motor and sensory neuropathy (3) and a miscellaneous group (5). We also
describe seven patients with Guillain-Barre syndrome (GBS) who required
long-term ventilatory support for over 6 months to 7 years after the
initial illness. Respiratory insufficiency occurred as a consequence of
respiratory muscle weakness, impaired bulbar function and restrictive lung
defects. In some groups presentation was with progressive nocturnal
hypoventilation culminating in acute respiratory failure. Five patients
with GBS or chronic idiopathic demyelinating neuropathy were weaned from
ventilatory support up to 18 months after the initial illness. The
remaining 24 patients required continuous or nocturnal ventilatory support
using intermittent positive-pressure ventilation (13), negative pressure
ventilation (4), nasal-mask-delivered intermittent positive-pressure
ventilation (4), nasal-mask-delivered continuous positive-pressure
ventilation (3), mouthpiece-assisted ventilation by day (2) and rocking bed
(1). None have been weaned from support after a period of ventilation
ranging from one month to 10 years. Eight patients have subsequently died.
相似文献
129.
INTRODUCTION. It is not well known how many Small Volume Prostate Cancers (SVPC) may host high grade (Gleason pattern 4/5) or have extraprostatic extension in particular in the national setting. Features of SVPC are very interesting since they raise controversies in diagnosis and have important clinical implications in treatment strategies. The diagnosis may be difficult and the treatment ranges from active surveillance to radical surgery. AIM. We evaluate clinical and pathological features of SVPC in surgical specimens of patients who underwent biopsy and radical prostatectomy. METHODS. We analysed a consecutive series of 849 radical prostatectomies performed between 2005 and 2008. Inclusion criteria were: biopsy specimen available, pathological tumor volume analysis according to standard criteria, whole-mount section 3 mm step analysis according to Stanford protocol, clinical parameters (PSA, DRE, number of core biopsy taken). Exclusion criteria: any hormonal manipulation before surgery and cT1A/B stage. Data were analysed using SPSS for statistical comparison. RESULTS. 238 patients were evaluated. SVPC<0.5 cc was observed in 58 (24.3%). Overall in 17/58 (29.3%) a clinical/pathological relevant disease was observed. In 16/58 (27.5%) pathological Gleason Score (GS) was 7-8, in 5/58 (9%) pathological stage was T3. The number of tumor foci was >1 in 78.3%, tumor-involving in both lobes in 55%. Unifocal disease was observed in 22%. Clinically relevant disease is significantly associated with total cancer volume (0.20 versus 0.31, p 0.007), but not to tumor foci (2.5 versus 2.0). PSA, age, no. of positive cores, DRE were not predictive of clinical relevant disease. Six of 17 (35%) cases with SVPC - who were in the low risk category (PSA <10, biopsy Gleason score <7 and negative DRE), had clinical relevant disease. CONCLUSION. SVPC are clinically relevant in 29.3% since they have a Gleason pattern 4 (27.5%) or have only pathological T3 (9%). Early diagnosis techniques and treatments have to consider that SVPC prostate cancer may contain high risk disease in 1/4 of cases. Clinical parameters are not useful to accurately detect high risk SVPC. 相似文献
130.