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101.
We report the successful long-term engraftment of normal male donor bone marrow (BM) transfused into noncytoablated female mice, challenging the assumption that "niches" need to be created for marrow to engraft. We have used chromosomal banding and Southern blot analysis to identify transplanted male marrow cells, and shown the long-term stability of the chimeric marrows. Balb/C, BDF1, or CBA-J female hosts (no irradiation) received for 5 consecutive days 40 x 10(6) male cells (per day) of the same strain, and repopulation patterns were observed. Parallel studies were performed using tibia/femur equivalents of normal marrow or marrow from Balb/C mice pretreated 6 days previously with 150 mg/kg 5-fluorouracil (5-FU). Chromosome banding techniques showed that 5% to 46% of marrow cells were male 3 to 9 months posttransplant with normal donor marrow. Southern blot analysis, using the pY2 probe, showed continued engraftment at 21 to 25 months posttransplant, ranging from 15% to 42% male engrafted cells in marrow. Normal donor male marrow engrafted significantly better than 5-FU-pretreated male marrow as shown 1 to 12 months posttransplant in non-cytoablated female recipients. Percentages of male engrafted cells in BM ranged from 23% to 78% for recipients of normal donor marrow and from 0.1% to 39% for recipients of 5-FU marrow. Mean engraftment for 6 mice receiving normal marrow was 38%, whereas that for 6 mice receiving post-5-FU marrow was 8%, as assayed 1 to 3 months posttransplant. At 10 to 12 months, mean engraftment for the normal donor group was 46%, compared with 16% for the 5-FU group. The patterns of engraftment with normal and 5-FU marrow were similar for spleen and thymus. These results show that long-term chimerism can be established after transplantation of normal donor marrow to normal nonirradiated host mice and indicate that marrow spaces do not have to be created for successful engraftment. They suggest that transplanted marrow competes equally with host marrow for marrow space. Finally, these data show that post-5-FU Balb/C male marrow is markedly inferior in the repopulation of Balb/C female host marrow, spleen, and thymus, and suggest that this population of cells may not be the ideal population for gene transfer studies.  相似文献   
102.
Mononuclear cells (MNC) isolated by density centrifugation of cord blood and healthy bone marrow, and of peripheral blood (PB) from patients treated with granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF after chemotherapy, were double-stained with anti CD34 monoclonal antibody (MoAb) (8G12) versus anti CD45, CD45-RB, CD45- RO, and CD45-RA, respectively, and analyzed by flow cytometry. In all specimens, CD34+ MNC co-expressed CD45 at a low level and the expression of CD45-RB was similar or slightly higher. Most CD34+ MNC were negative for CD45-RO, a weak coexpression was only seen in some bone marrow (BM) and blood samples. In contrast, CD45-RA could subdivide the CD34+ population into fractions negative, dim (+), and normal positive (++) for these subgroups, and typical staining patterns were observed for the different sources of hematopoietic cells: in BM, most CD34+ MNC were RA++. In PB, their majority was RA++ after G-CSF but RA+ or RA- after GM-CSF. In cord blood, the hematopoietic progenitors were mainly RA-/RO-. Semisolid culture of sorted CD34+ MNC showed that clusters and dispersed (late) colony-forming unit-GM (CFU- GM) originated from 34+/RA++ cells, while the 34+/RA- MNC formed compact and multicentric, both white and red colonies derived from early progenitors. Addition of 20 ng stem cell factor per milliliter of medium containing 34+/RA- cord blood MNC led to a change of many burst- forming unit-erythrocyte (BFU-E) to CFU-mix which was not, at least to this extent, seen in blood and BM. We conclude that early myeloid CD34+ cells are 45+/RA-. Because this population excludes 34+/19+ B cells and 33+ myeloid cells, both of which are RA++, two-color flow cytometric analysis using CD34 and CD45-RA facilitates the characterization and quantification of early myeloid progenitor cells.  相似文献   
103.
104.
We evaluated the possible influence of early levodopa treatment on the mortality of Parkinson's disease (PD). One hundred forty-five consecutive parkinsonian patients initiated treatment with levodopa between 1970 and 1983. Ninety-eight of those started levodopa therapy 2 or more years after symptom onset, while 47 received levodopa within the 1st 2 years of the disease. At the end of follow-up, in December 1985, 49 patients had died. Mortality was 2.5 times higher among patients who delayed initiation of levodopa therapy 2 or more years than among those who initiated the therapy earlier. Age and disease severity were the most significant predictors of survival after initiation of levodopa treatment. The risk of death was 10% higher every year of age increase and was 2 and 4 times higher, respectively, for patients at Hoehn and Yahr stages II and III than for patients at Hoehn and Yahr stage I. When we controlled for the effect of age and disease severity on mortality, the cumulative death probability was no longer significantly higher among patients who delayed levodopa treatment than among patients treated within 2 years from disease onset. As far as mortality is concerned, the results show that the time of levodopa treatment initiation during PD has no influence and the drug can be introduced as soon as indicated by the severity of the disease progression.  相似文献   
105.
106.
BACKGROUND: The self-locating catheter invented by Nicola Di Paolo has been used increasingly in Italy and elsewhere since 1994, with about a thousand patients currently implanted every year. Twelve grams of tungsten inserted into the tip of the conventional Tenckhoff catheter during extrusion does not significantly change its form, but suffices to keep the tip firmly in the Douglas cavity. OBJECTIVE: The aim of the present study was to confirm our preliminary results in a large population of peritoneal dialysis patients. SETTING: 16 Italian nephrology departments. RESULTS: In addition to confirming the validity of the new catheter, the present results show that patients with the new catheter have fewer episodes of peritonitis, tunnel infection, cuff extrusion, catheter malfunction, obstruction, and leakage. CONCLUSION: The present multicenter control study confirms preliminary results and demonstrates that complications of peritoneal dialysis, such as cuff extrusion, infection, peritonitis, early leakage, and obstruction, are statistically less frequent in patients with self-locating catheters than in patients with classic Tenckhoff catheters.  相似文献   
107.
5 consecutive cases of acute GBS were treated by plasmapheresis (PP). Clinical features and results of therapy have been compared with those of 10 consecutive acute GBS cases untreated by PP. PP treatment, applied early during the phase of deterioration, seemed to stop deficit progression, thus eliminating the stationary stage and triggering recovery immediately. Complete recovery seemed to occur comparatively faster than in the untreated group.
Sommario Abbiamo trattato con plasmaferesi 5 casi consecutivi di Sindrome di Guillain-Barré acuta. Le caratteristiche cliniche ed i risultati del trattamento sono stati confrontati con quelli relativi a 10 casi consecutivi precedentemente osservati e non trattati con plasmaferesi. Il trattamento con plasmaferesi, applicato precocemente, ancora in fase di deterioramento, sembra arrestare la progressione sintomatologica, eliminando la fase di stazionarietà e dando inizio ad un immediato recupero; il recupero completo appare occorrere più precocemente nei pazienti trattati.
  相似文献   
108.
109.
1. The aim of the present study was to evaluate whether postural blood pressure (BP) change could predict office-daytime BP disparity and the nocturnal BP fall in young, mild essential hypertensives. We investigated 411 males aged between 18 and 45 years with never treated borderline to mild hypertension. BP was measured three times after a 5 min rest in the supine position and thereafter three times after 2 min of standing. The mean of six BP measurements obtained during two visits in the lying position was defined as office BP. 2. Twenty-four hour ambulatory BP monitoring was performed with either the A and D TM-2420 model 7 or the ICR Spacelabs 90207. BP values were averaged for day—and nighttime periods. The nocturnal BP fall was defined as the difference between the average day—and night-time BP. 3. The standing-lying difference was significantly inversely correlated with the office-daytime difference for both systolic blood pressure (SBP) (r = -0.34, P 0.001) and diastolic blood pressure (DBP) (r = -0.24, P 0.001). These correlations did not change when the obese subjects (body mass index > 30 kg/m2) were excluded from the analysis. No significant correlation between standing-lying difference and nocturnal BP fall was found. 4. Our results indicate that white coat hypertension assessed as the office-daytime BP disparity is partially related (in a negative fashion) to the BP reaction to standing. The postural BP change does not predict nocturnal BP fall in young, mild essential hypertensives.  相似文献   
110.
Summary The uptake of foreign particles by mouse and human macrophages influenced by various metabolic inhibitors was examined in order to obtain further informations about the energy-dependent mechanisms which are involved in the phagocytic process. The inhibitors employed were iodoacetate, fluoroacetate, fluoride, malonate, sodium azide, 2-4-dinitrophenol, cycloheximide and ouabain. These substances were rested on monolayer cultures and the phagocytosis assay was performed by using zymosan suspension in the nutrient media. The quantitation of phagocytosis was obtained by the direct count of intracellular zymosan particles (immersion microscopy, 100x) and the results were evaluated and compared by biometrical analysis. The effects of these inhibitors on phagocytosis and their relation with the metabolic intracellular pathways are discussed.  相似文献   
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