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71.
72.
A series of lymphoblastoid cell lines (LCLs) have been established by in vitro infection of fetal bone marrow and fetal liver cells with Epstein-Barr virus (EBV). While most lines showed the usual mature B cell phenotype, a small proportion were cytoplasmic and surface immunoglobulin (Ig) heavy and light chain negative. Analysis of gene rearrangements indicated that the Ig- lines were either germ-line or nonproductively rearranged when probed for JH and were in germ-line configuration for C chi; no mu or chi mRNA could be detected in such cells. Precursor B cell lines were indistinguishable from their normal Ig+ counterparts in their expression of a wide variety of cell surface markers including "activation" antigens usually associated with the lymphoblastoid state; even the single LCL showing germ-line heavy and light chain genes expressed B lineage-specific cell surface antigens. However, the Ig- lines were distinct from their Ig+ counterparts in three important respects: (a) they grew much more slowly and achieved lower saturation densities, (b) they showed unusually high proportions (8-16%) of cells in EBV-productive cycle, and (c) they contained unusually high proportions (up to 40%) of cells expressing free joining (J) chain. These results suggest that precursor B cells differ in their response to the growth-transforming effects of EBV such that the virus-cell interaction in precursor B cell lines is inherently less stable than in conventional LCL. In particular there may be a greater movement of cells out of cycle and along the B cell maturation pathway. It is possible that such movement leads in individual cells either to virus replication or to a "sterile" plasmacytoid differentiation with J chain expression in the absence of Ig synthesis.  相似文献   
73.
Estrogen deficit in postmenopausal women causes urogenital atrophy, which is responsible for a wide range of urinary disorders (urinary incontinence, urge incontinence, recurrent urinary infections) and genital disorders (prolapse, dispareunya, vaginal dryness). The efficacy of estrogen therapy on urinary incontinence is not yet demonstrated, but it is widely recognized that the topical use of estrogens lowers the risk of recurrent urinary infections and improves urogenital atrophy.  相似文献   
74.
Profound bilateral loss of vestibular hair cell function can cause chronically disabling loss of balance and inability to maintain stable vision during head and body movements. We have previously shown that chinchillas rendered bilaterally vestibular-deficient via intratympanic administration of the ototoxic antibiotic gentamicin regain a more nearly normal 3-dimensional vestibulo-ocular reflex (3D VOR) when head motion information sensed by a head-mounted multichannel vestibular prosthesis (MVP) is encoded via rate-modulated pulsatile stimulation of vestibular nerve branches. Despite significant improvement versus the unaided condition, animals still exhibited some 3D VOR misalignment (i.e., the 3D axis of eye movement responses did not precisely align with the axis of head rotation), presumably due to current spread between a given ampullary nerve's stimulating electrode(s) and afferent fibers in non-targeted branches of the vestibular nerve. Assuming that effects of current spread depend on relative orientation and separation between nerve branches, anatomic differences between chinchilla and human labyrinths may limit the extent to which results in chinchillas accurately predict MVP performance in humans. In this report, we describe the MVP-evoked 3D VOR measured in alert rhesus monkeys, which have labyrinths that are larger than chinchillas and temporal bone anatomy more similar to humans. Electrodes were implanted in five monkeys treated with intratympanic gentamicin to bilaterally ablate vestibular hair cell mechanosensitivity. Eye movements mediated by the 3D VOR were recorded during passive sinusoidal (0.2-5?Hz, peak 50°/s) and acceleration-step (1000°/s(2) to 150°/s) whole-body rotations in darkness about each semicircular canal axis. During constant 100?pulse/s stimulation (i.e., MVP powered ON but set to stimulate each ampullary nerve at a constant mean baseline rate not modulated by head motion), 3D VOR responses to head rotation exhibited profoundly low gain [(mean eye velocity amplitude)/(mean head velocity amplitude)?相似文献   
75.
Haploidentical stem cell transplantation (haplo-SCT) with post-transplant cyclophosphamide (PT-Cy) is an alternative treatment for acute myeloid leukemia (AML) patients who lack HLA-matched donors. Relapse after haplo-SCT remains a major concern, especially after nonmyeloablative conditioning regimens. Promising results were reported for TBF-based conditioning regimens (thiotepa, busulfan, and fludarabine) in patients transplanted from different categories of donors and for various disease types but not specifically in PT-Cy haplo-SCT for AML. Here we evaluate the outcome of 100 AML patients who received haplo-SCT with PT-Cy after TBF conditioning regimens (reduced-intensity conditioning, n = 77; myeloablative conditioning, n = 23) in 2 transplant programs. Cumulative incidences of grades III to IV acute and moderate or severe chronic graft-versus-host disease (GVHD) were 7% and 14%, respectively. NRM at 2 years was 28%, significantly influenced by disease status at haplo-SCT (first complete response [CR1] versus advanced AML: 16% versus 38%, P = .016) but not by conditioning intensity or age. The cumulative incidences of relapse at 2 years were 17% and 24% in CR1 and advanced AML, respectively (not significant). Progression-free survival, overall survival, and GVHD and relapse-free survival at 2 years were 67%, 71%, and 49% in CR1 patients, respectively, whereas comparative values in patients with advanced disease were 37%, 41%, and 32%. Our study suggests that TBF conditioning for PT-Cy haplo-SCT is safe and effective for AML patients in CR1. In patients with more advanced disease, the relatively low incidence of relapse seems counterbalanced by a high nonrelapse mortality, underlining the need for alternative strategies to decrease relapse risk, without increasing the intensity of conditioning regimen.  相似文献   
76.
Using a method which allows simultaneous flow cytometric detectionof cell surface markers and 5-bromo-2'-deoxyuridine (BrdU) incorporation,the distribution and proliferative behavior of B lineage subpopulationswas studied in intact adult mice. In the bone marrow we coulddefine two subsets of B cells on the basis of differential expressionof the pan-B cell marker B220 and of membrane-associated µand immunoglobulin heavy chains. B220dullµ+– Bcells were found to emerge from rapidly dividing cells and probablyrepresent B cells recently generated from B220dullµpie-B cells. In contrast, oniy few, If any, of the B220brightµ++B cells were labeled with BrdU after a period of 8 days, suggestingthat these cells represent long-lived B cells residing in thebone marrow. Analysis of BrdU-Incorporation into splenic B cellsshowed that only 20% of these cells had gone through cell divisionduring the preceding 8 days. Almost none of the B cells in theperitoneum, a large fraction of which belongs to the Ly1 B subset,were labeled with BrdU over a period of 7 days in 8-month-oldanimals.  相似文献   
77.
Conclusion In summary,Acinetobacter colonization or infection may originate from the patients' own flora under the pressure of antimicrobial selection, the hands of staff members, or contaminated equipment. Transmission ofAcinetobacter strains between patients occurs primarily via the hands of health care workers. In outbreak situations, colonized or infected patients and the inanimate environment, which can be secondarily contaminated, are the main reservoirs in the hospital setting for crosstransmission. However, colonized or infected patients seem to be the most important source of cross-contamination, as epidemic strains spread easily throughout different wards. Especially in prolonged outbreaks in which control efforts such as proper hand washing, glove changing, and restriction of antimicrobial agents are ineffective and specific sources such as contaminated equipment are not identified, the source of the epidemic strain is likely the patients' inanimate dry environment [45, 48].In outbreak situations it is necessary that isolatedAcinetobacter strains are identified to the genomic species level and then typed before epidemiological conclusions can be drawn, becauseAcinetobacter spp. are ubiquitous organisms [3, 31].  相似文献   
78.
The E test was evaluated in comparison with reference agar methods (National Committee for Clinical Laboratory Standards) for the susceptibility testing of 248 Pseudomonas aeruginosa isolates from bladder-catheterized patients against nine antibiotics. The E-test MICs correlated well with those determined by the agar dilution and disk diffusion reference methods (88 and 92.5% within 1 log2 dilution step, respectively), confirming that the E test is a reliable method for the determination of MICs of antibiotics for catheterization-associated P. aeruginosa isolates.  相似文献   
79.
Data on the economic burden of lower respiratory tract infections (LRTI) in young children are lacking in Germany. The objective of the cost-of-illness study was to estimate the economic impact of community-acquired LRTI and nosocomial LRTI as well as of infections due to respiratory syncytial virus (RSV), parainfluenza viruses (PIV) and influenza viruses (IV). The economic analysis is part of the PRI.DE study, a prospective, multi-centre, population-based epidemiological study on the impact of LRTI in children aged 0 to 36 months in Germany. The analysis includes children with community-acquired infections (1329 cases treated as outpatients, 2039 cases treated as inpatients) and nosocomial infections (90 cases). Medical services consumed were generated by chart abstraction and parental expenses data by telephone interviews within four weeks after physician visit or hospitalisation. Costs were evaluated from following perspectives: third party payer, parent and society. Total costs for outpatient treatment are €123 per LRTI case. Stratified by virus type, total costs per case are €163 (RSV), €100 (PIV) and €223 (IV). Total costs per hospitalised LRTI case amount to €2579. Stratified by virus type, total costs per case are €2772 (RSV), €2374 (PIV) and €2597 (IV). Total costs per nosocomial case are €2814. Economic burden due to LRTI is €213 million annually. It is concluded that treatment of LRTI in children up to age three causes a considerable economic burden in Germany. Presented results are the first data describing the economic burden of LRTI in young children assessed by means of the incidence data for Germany. This cost-of-illness study provides basic data for further decision-making, focusing on the economic assessment of preventive strategies for RSV, PIV and IV infections.  相似文献   
80.
Prolactinomas are rare in children and adolescents but well studied in adults. Dopamine agonists are the treatment of choice for all ages. Bromocriptine is the only agonist approved for use in pediatric patients by the FDA. Cabergoline, a second-generation ergot derivative with a longer half-life, has been used in resistant prolactinomas and as first-line treatment in adults. The authors describe an adolescent boy with a pituitary macroadenoma with an initial prolactin level of 73,777 ng/mL. After failing to respond to bromocriptine and standard-dose cabergoline, he responded well to very high daily doses of cabergoline (1.5 mg daily), with a current prolactin level of 726 ng/mL and notable reduction in tumor size. Escalating doses of cabergoline should be considered in pediatric patients with dopamine-resistant prolactinomas.  相似文献   
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