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91.
Methylation, deletions, and amplifications of cancer genes constitute important mechanisms in carcinogenesis. For genome-wide analysis of these changes, we propose the use of NotI clone microarrays and genomic subtraction, because NotI recognition sites are closely associated with CpG islands and genes. We show here that the CODE (Cloning Of DEleted sequences) genomic subtraction procedure can be adapted to NotI flanking sequences and to CpG islands. Because the sequence complexity of this procedure is greatly reduced, only two cycles of subtraction are required. A NotI-CODE procedure can be used to prepare NotI representations (NRs) containing 0.1-0.5% of the total DNA. The NRs contain, on average, 10-fold less repetitive sequences than the whole human genome and can be used as probes for hybridization to NotI microarrays. These microarrays, when probed with NRs, can simultaneously detect copy number changes and methylation. NotI microarrays offer a powerful tool with which to study carcinogenesis.  相似文献   
92.
OBJECT: The capability of osteogenic protein (OP)-1 to induce bone formation has led to an increasing interest in its use in fusion surgery. This prospective study examines the safety and efficacy of OP-1 use in patients considered to be at a high risk for developing pseudarthrosis following reconstructive spinal surgery. METHODS: Outcome measures included documentation of adverse events, radiographic evaluation of fusion by an independent musculoskeletal radiologist blinded to treatment, the Oswestry Disability Index (ODI), and the 36-Item Short Form Health Survey (SF-36). The health-related quality of life (HRQOL) assessments (ODI and SF-36) were given at baseline and at 3, 6, 12, 18, and 24 months after the surgical OP-1 implant. RESULTS: The study consisted of 17 male and 13 female patients, with a mean age of 53 years (range 20-77 years). Fourteen patients underwent operations for cervical disease, and 16 for lumbar disease, with a median postoperative follow-up of 24 months (range 13-46 months). There were significant improvements in the physical health (from 28.7 +/- 1.5 to 34.2 +/- 3; p = 0.025) and mental health (from 43.7 +/- 2 to 47.5 +/- 3.1; p = 0.015) summary scores on the SF-36. The mean postoperative ODI score at 6, 9, 12, and 18 months was significantly lower than the baseline ODI score, after taking into consideration a 10-point measurement error (p = 0.0003, p = 0.003, p = 0.004, and p = 0.032, respectively). At 24 months, however, the differences in ODI scores were no longer significant. Of the 30 patients, 24 (80%) were deemed to have a solid fusion. There were no allergic reactions to OP-1 and no symptomatic postoperative hematomas. CONCLUSIONS: Our results suggest that the use of OP-1 is safe and may contribute to high fusion rates, as demonstrated by radiographs, reduced levels of disability, and improved HRQOL in patients considered to be at a high risk for developing a nonunion after spinal reconstructive surgery.  相似文献   
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Coherence functions in cortical electrical potentials in the theta (4–7 Hz) and alpha ranges (8–13 Hz) recorded during the formation and testing stages of a visual set to facial images bearing an emotional expression (an angry face) were studied in healthy adult subjects (n = 35). Differences in the spatial synchronization between theta and alpha potentials were seen, especially in rigid forms of the set, in which cases of erroneous perception of facial expressions were seen with contrast and assimilative illusions. This group of subjects (n = 23) showed increases in theta potentials between the dorsolateral areas of the frontal cortex (the orbitofrontal cortex) and the temporal area in the right hemisphere. A mechanism is proposed for the development of visual illusions. Analysis of the coherence functions of cortical potentials in the theta and alpha ranges generates a “window” which can be used to study the operation of the two functional systems integrating brain activity, i.e., the corticohippocampal and frontothalamic, in the perception of a facial expression. The frontothalamic system is associated with more diffuse types of cortical activation, especially in its anterior areas. The theta rhythm system evidently facilitates integration of the frontal cortex with the temporal area in the right hemisphere and the connections of the latter with the parietal and central zones in both hemispheres.  相似文献   
96.
By the method of laser Doppler fluometry microcirculation in gingival tissues was studied in the region of bearing implants in cases of making prosthetics for patients with full secondary adentia. It was established that after functional loading of the bearing implants in microcirculatory bed of gingival tissues hyperemia was developed that was cut short in 3 months that testified to normalization of tissue blood flow.  相似文献   
97.
Summary. This report evaluates the haemostatic efficacy of recombinant factor VIIa (rFVIIa) and activated prothrombin complex concentrate (APCC) in patients with haemophilia and high responding inhibitors who underwent major and minor surgery. Data pertaining to surgeries from 2001 to 2009 at a single centre were retrospectively analysed. During this period, 53 surgical procedures were performed in 30 haemophiliacs with high responding inhibitors. Mean age was 16.2 ± 9.4 years. Eleven major surgeries in 4 patients, 41 radioisotope synovectomies (RS) and one circumcision classified as minor surgery in 28 patients were performed. Among the major surgery procedures, four were treated with rFVIIa, five with APCC and two with sequential use of APCC and rFVIIa. We used rFVIIa at the dosage of 80–120 μg kg?1 every 2 h and APCC 100 IU kg?1 every 12 h for the major surgery. When performing RS, we used rFVIIa in 18 patients with 26 target joints and APCC in 9 patients with 15 target joints. Three consecutive doses of rFVIIa (90 μg kg?1) were used at 2‐h intervals followed by additional three doses at 6‐h intervals. The initial dose of APCC was 75 IU kg?1 followed by a second and third dose of 50 IU kg?1 at 12‐h intervals. APCC and rFVIIa demonstrated excellent efficacy in our major and minor surgical interventions [100% (22/22) and 94% (31/33), respectively]. We had only two bleeding complications with rFVIIa. There were no thromboembolic complications. APCC and rFVIIa provide an effective and safe first line haemostatic therapy for inhibitor‐positive haemophiliacs, allowing both major and minor surgery to be successfully performed.  相似文献   
98.
Summary. The activities of ‘expert patients’ or ‘patient tutors’, who help educate their peers, are gaining recognition in the health care system. This study investigates the role played by such patients in therapeutic education programmes organized by caregivers to validate the role of patients in implementing the therapeutic education of haemophilic patients and to define the skills required for such activities. This study employs the consensus methodology recommended by France’s National Authority for Health. The working group includes seven caregivers from Hemophiliac Treatment Centers (HTCs) and three patients from the French Association of Hemophiliacs (FAH). The role of patients in haemophilia education is recognized. Patients participating in the education of their peers are referred to as ‘patient resources’. A patient resource should be an adult, a volunteer and live in the same region as his peers. Candidates are chosen by the FAH and the HTCs to serve based on their motivation to facilitate the education of other patients as well as on their psychological and pedagogical aptitudes. A patient resource participates in the conception and administration of therapeutic education programmes. He also mediates between the caregivers and the patients. He ensures that the patients understand the material and are able to apply their knowledge in daily life. His activities are governed by professional ethics. Seven categories of skills were defined, permitting the group to determine precisely which skills are required to function as a patient resource. Supervision of the patients is planned to reinforce reflexive practices in the patients. Evolution of the health care system has led patients to become involved in therapeutic education. This phenomenon calls for a framework to be developed and an evaluation of its eventual effects.  相似文献   
99.
Background and Aim:  Chronic liver failure results in the decrease of the number of functioning hepatocytes. It dictates the necessity of using exogenous viable cells or/and agents that can stimulate hepatic regenerative processes. Fetal liver contains both hepatic and hematopoietic stem cells with high proliferative potential, which may replace damaged cells. Also, immature cells produce fetal-specific factors which may support the injured liver. Our aim was to test the ability of human fetal liver cells and cell-free fetal-specific factors of non-hepatic origin to stimulate recovery processes in an experimental model of carbon tetrachloride–induced cirrhosis in rats.
Methods:  Cirrhotic rats were intrasplenically injected with fetal liver cells (1 × 107 cells/0.3 mL medium) or cell-free fetal-specific factors (0.3 mL/1 mg protein). Control groups received medium alone. Serum indexes, hepatic functions, and morphology were evaluated for 15 days.
Result:  Human fetal liver cell transplantation was shown to abrogate the mortality of cirrhotic animals, to improve serum markers, and to restore liver mitochondrial function and detoxification. Morphological patterns of liver recovery were observed by histology. In comparison, an injection of fetal-specific factors produced similar functional recovery, whilst a more limited liver regeneration was observed by histology.
Conclusions:  The positive effects of fetal liver cell and cell-free fetal-specific factors in experimental cirrhosis may result from the presence of stage-specific factors activating hepatocellular repair.  相似文献   
100.
In 2004, we tested all patients with newly diagnosed tuberculosis (TB) for HIV in Kiev City. The results were compared to information from medical records of 2002, when co-infection prevalence was 6.3%. Of 968 TB patients, 98 (10.1%) were HIV infected. TB-HIV co-infection is increasing, especially in injecting drug users.  相似文献   
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