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81.
Stem cell therapy has showed considerable potential in the treatment of stroke over the last decade. In order that these therapies may be optimized, the relative benefits of growth factor release, immunomodulation, and direct tissue replacement by therapeutic stem cells are widely under investigation. Fundamental to the progress of this research are effective imaging techniques that enable cell tracking in vivo. Direct analysis of the benefit of cell therapy includes the study of cell migration, localization, division and/or differentiation, and survival. This review explores the various imaging tools currently used in clinics and laboratories, addressing image resolution, long-term cell monitoring, imaging agents/isotopes, as well as safety and costs associated with each technique. Finally, burgeoning tracking techniques are discussed, with emphasis on multimodal imaging.  相似文献   
82.
Using Southern blotting for the diagnosis of clonality in peripheral T-cell lymphomas (PTCLs), analysis of the T-cell receptor (TCR) γ gene rearrangement was shown to be more informative than that of the TCR β gene rearrangement. In order to amplify every VJγ rearrangement, a polymerase chain reaction (PCR) procedure using newly designed GC-clamp primers has been developed. All primers can be mixed in a single multiplex PCR. PCR products are analysed by denaturing gradient gel electrophoresis (DGGE), providing tumour-specific imprints inasmuch as the procedure characterizes N sequence polymorphism at the VJ junctions. In a series of 30 PTCL cases, the PCR procedure demonstrated 27 cases to be clonally rearranged and failed in three cases. PCR was more accurate than Southern blotting, showing 47 rearranged γ alleles, four of which were undetectable on the Southern blot. When lymphomas were studied at different sites and at relapse, the DGGE pattern remained unchanged. In PTCL, the proposed PCR is helpful for the diagnosis and staging of the disease and should improve the follow-up monitoring. The undetectability of clonal rearrangements in a few cases is discussed in the light of concepts of lymphomagenesis and T-cell differentiation.  相似文献   
83.
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality.  相似文献   
84.
85.
Genetic mediated physiological processes that rely on both pharmacological and nutritional principles hold great promise for the successful therapeutic targeting of reduced carbohydrate craving, body-friendly fat loss, healthy body recomposition, and overall wellness. By integrating an assembly of scientific knowledge on inheritable characteristics and environmental mediators of gene expression, we review the relationship of genes, hormones, neurotransmitters, and nutrients as they correct unwanted weight gain coupled with unhappiness. In contrast to a simple one-locus, one-mechanism focus on pharmaceuticals alone, we hypothesize that the use of nutrigenomic treatment targeting multi-physiological neurological, immunological, and metabolic pathways will enable clinicians to intercede in the process of lipogenesis by promoting lipolysis while attenuating aberrant glucose cravings. In turn, this approach will enhance wellness in a safe and predictable manner through the use of a Genetic Positioning System (GPS) Map. The GPS Map, while presently incomplete, ultimately will serve not only as a blueprint for personalized medicine in the treatment of obesity, but also for the development of strategies for reducing many harmful addictive behaviors and promoting optimal health by using substances compatible with the body’s immune system.  相似文献   
86.
This study investigated the ability of aphasic patients with mild auditory comprehension problems to respond to synthetic speech produced by an inexpensive speech synthesizer attached to a personal computer. Subjects were given four practice sessions with synthetic speech; testing of synthetic speech comprehension was performed during Sessions 1 and 4. During testing, aphasic subjects' comprehension of synthetic speech was compared with their comprehension of natural speech on four tasks: (a) picture identification, (b) following commands, (c) yes/no questions, and (d) paragraph comprehension with yes/no questions. Aphasic subjects comprehended natural speech better than synthetic speech in Session 1 but not in Session 4. Their synthetic speech scores improved between Sessions 1 and 4. There was also a significant difference among scores on the four tasks for both sessions. The means for picture identification were highest, followed by yes/no questions, commands, and finally paragraph comprehension for both sessions. Although performance by some subjects on some tasks was accurate enough to indicate that an inexpensive speech synthesizer could be a useful tool for working with mild aphasic patients, considerable caution in selecting both tasks and patients is warranted.  相似文献   
87.
88.
Mass casualty events due to terror attacks have escalated throughout Israel since September 2000, with a high proportion of these events occurring in the Jerusalem area. Immediately after news of a large-scale terror attack is received, family/public information centers are set up in all local hospitals to meet the needs of members of the public who call or arrive at hospitals anxious to obtain information about relatives who may have been at the site of the attack. The most urgent task facing these centers is the quick and accurate identification of victims whose identity is in question. To date, some 3000 casualties have been treated at Hadassah Hebrew University Medical Center (Hadassah), a level I trauma center. This number accounts for nearly half of Israel's total number of casualties from terror attacks during this period. Extensive experience has led the hospital to develop a unique organizational model for its family/public information center; in this model, members of the nursing staff identify casualties. The experience and knowledge gained in dealing with terror events also can be applied to other types of mass casualty events, such as major road or work accidents.  相似文献   
89.
The survival rate of children with localized orbital rhabdomyosarcoma is now greater than 90% 3 years after diagnosis as a result of advances in radiation and chemotherapy. Ninety percent of these children develop cataracts within 1 to 4 years after the completion of radiotherapy. The correction of aphakia in these children is complicated by the concurrent keratoconjunctivitis and dryness associated with radiotherapy. Three patients with a diagnosis of orbital rhabdomyosarcoma underwent treatment for uniocular cataract. Two of the patients were unable to use extended wear contact lenses. Both underwent epikeratophakia with poor results. One patient who had clinically significant ocular drying prior to cataract extraction underwent successful implantation of an intraocular lens as a primary procedure, with excellent visual results. Clinicians should be aware of the difficulties associated with contact lens wear and epikeratophakia tissue lenses in children who have had high doses of radiation for orbital rhabdomyosarcoma. Such patients are probably best served by primary intraocular lens implantation or by preservation of the posterior capsule at the time of cataract extraction to allow secondary lens implantation if contact lens wear is unsuccessful.  相似文献   
90.
The BB/Wor rat develops spontaneous insulin dependent diabetes mellitus (DM) and lymphocytic thyroiditis (LT). We have recently demonstrated that immunization of BB/Wor rats with allogeneic thyroglobulin (Tg) induces LT at an early age. The incidence of spontaneous and Tg induced LT is extremely variable among different BB/Wor sublines. It has been shown that high iodine diet significantly increases the incidence of spontaneous lymphocytic thyroiditis (LT) and low iodine diet significantly decreases the incidence of LT in genetically predisposed BB/Wor rats. Recent studies on thyroglobulin (Tg) induced LT in chicken and mouse have shown that iodine rich Tg is far more antigenic than Tg with a low iodine content, suggesting that a high iodine diet increases the immunogenicity of Tg molecule. In order to determine whether the extent of Tg iodination would affect its immunogenicity in the BB/Wor rats, the current study was carried out. Normal iodine Tg (NTg) or low iodine Tg (LTg) was obtained from thyroids of rats that were placed on regular diet or regular diet plus 0.5% methimazole, respectively. 120 rats from the NB (highly susceptible) and BB (low susceptible) sublines were randomized in three groups. Immunization was carried out with a 1:1 emulsion of complete Freund's adjuvant (CFA) and LTg, NTg (0.6 mg/rat) or saline at 30 and 37 days of age. Since spontaneous LT rarely occurs before age 75 days, rats were sacrificed at age 65 days to specifically study Tg induced LT. Immunization with NTg induced LT in 31% of the NB rats, but not in the BB subline. LTg did not induce LT in either subline.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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