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991.
Paul Telfer Helen Devereux Brian Colvin Sheila Hayden Geoffrey Dusheiko Christine Lee 《Haemophilia》1995,1(1):54-58
We have conducted a controlled trial in 20 haemophilic patients in which intravenous recombinant interferon alpha-2a, 3 mega units thrice weekly, was used to treat chronic hepatitis C infection. The study endpoints included complete and paritial normalization of serum ALT, and loss of serum HCV RNA as determined by polymerase chain reaction (PCR). Interferon treatment was effective, and resulted in improvement in ALT in nine (45%) and a loss of HCV RNA in five patients (26%), but a sustained normalization of ALT has been seen in only one case. Responses were poor in those with HIV coinfection or with HCV genotype 1 (Simmonds classification). Troublesome side-effects were reported in 80%. The occurrence of a factor VIIIc inhibitor during the study was possibly an autoimmune complication of interferon. In conclusion, we have shown lower response rates than those seen in post-transfusion hepatitis C infection and suspect that current interferon regimes are unlikely to influence the natural history of HCV infection in haemophilia. Consideration should be given to trials of higher dosage interferon, and of long-term maintenance therapy for those who relapse. 相似文献
992.
Badreddine Bencherif Angela S Guarda Carlo Colantuoni Hayden T Ravert Robert F Dannals J James Frost 《Journal of nuclear medicine》2005,46(8):1349-1351
The endogenous opioid system of the brain has been implicated in feeding behavior. Abnormal repeated activation of this system may constitute a neural substrate for the compulsive eating behavior observed in bulimia nervosa. This study examined the binding potential of the brain mu-opioid receptor (mu-OR) in bulimia nervosa. METHODS: Eight women with bulimia nervosa and 8 female controls underwent brain MRI followed by (11)C-carfentanil PET. Voxel-based methods were used to assess group differences in mu-OR binding between controls and bulimic subjects and to correlate mu-OR binding with the frequency of recent self-reported abnormal eating behaviors in bulimic subjects. RESULTS: mu-OR binding in the left insular cortex was less in bulimic subjects than in controls and correlated negatively with recent fasting behavior. CONCLUSION: Changes in mu-OR binding in the insula may be important in the pathogenesis or maintenance of the self-perpetuating behavioral cycle of bulimic subjects because the insula is the primary gustatory cortex and has repeatedly been implicated in the processing of the reward value of food. 相似文献
993.
GeorgeA. Hyatt EllenA. Schmitt JamesM. Fadool JohnE. Dowling 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(23):13298-13303
Application of exogenous retinoic acid (RA) to zebrafish during the initial stages of photoreceptor differentiation results in a precocious development of rod photoreceptors and an inhibition of cone photoreceptor maturation. The acceleration of rod differentiation is observed initially within the ventral retina 3 days after fertilization, following 24 hr of RA application, and within the dorsal retina 4 days after fertilization, following 48 hr of RA application. The differentiation of rods was impeded significantly when the synthesis of endogenous retinoic acid was inhibited by citral prior to the initial stage of rod differentiation. RA-treated embryos labeled for bromodeoxyuridine (BrdU) uptake revealed that RA exerts its effect on a postmitotic cell population within the developing retina. During normal development in zebrafish, rod differentiation is most robust within the ventral retina, a region previously shown to be rich in RA. Our data suggest that the RA signaling pathway is involved in the differentiation and maturation of both the rod and cone photoreceptors within the developing zebrafish retina. 相似文献
994.
995.
Expanded programme on immunization 总被引:1,自引:0,他引:1
K Keja C Chan G Hayden R H Henderson 《Rapport trimestriel de statistiques sanitaires mondiales》1988,41(2):59-63
The Expanded Programme on Immunization (EPI) was established in 1974 to develop and expand immunization programmes throughout the world. In 1977, the goal was set to make immunization against diphtheria, pertussis, tetanus, poliomyelitis, measles and tuberculosis available to every child in the world by 1990. Problems encountered by the Programme have included: lack of public and governmental awareness of the scope and seriousness of the target diseases; ineffective programme management; inadequate equipment and skills for vaccine storage and handling; and insufficient means for monitoring programme impact as reflected by increasing immunization coverage levels and decreasing incidence of the target diseases. When the EPI was initiated in 1974, fewer than 5% of children in developing countries were receiving a third dose of DPT and poliomyelitis vaccines in their first year of life. These coverage levels have now surpassed 50% in developing countries, and millions of cases of the target disease have been prevented. Over 700,000 measles deaths were prevented by immunization in developing countries in 1987, and an increasing number of neonatal tetanus deaths is now being prevented by maternal immunization and improved childbirth conditions. Poliomyelitis immunization efforts have been so successful that the Pan American Health Organization is leading a drive to eradicate poliomyelitis from the Americas by 1990. The successes of the Programme represent a major public health achievement, but much remains to be done.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
McArdle CB; Richardson CJ; Hayden CK; Nicholas DA; Crofford MJ; Amparo EG 《Radiology》1987,163(2):387-394
The authors prospectively evaluated 82 neonates, ranging in gestational age from 29 to 44 weeks postconception, with magnetic resonance (MR) imaging at 0.6 T. Twenty-two cases of hemorrhage in 15 infants were identified. Ultrasound (US) and computed tomography (CT) were superior to MR in the first few days after parenchymal hemorrhage, since at this time lesions were apparent on only T2-weighted images. After the first 3 days, MR was the single best modality because (a) hemorrhage on CT became imperceptible in the 2d week, whereas the high signal of hemorrhage on MR persisted for 2-11 weeks; (b) MR permitted rough dating of hemorrhage according to changes in signal intensity; and (c) MR was superior in identifying subdural or epidural hemorrhage. Because of the nonspecificity and restricted field of view of US and the inability of CT to depict hemorrhage after 7-10 days, the authors conclude that MR significantly improves the detection of intracranial hemorrhage in neonates. 相似文献
997.
To determine the effect of increasing supplementary oxygen flow during ventilation with the Laerdal pocket mask 24 subjects ventilated a modified recording mannikin for four 90 s periods using the mask with oxygen flows of 5 l, 10 l, 15 l and 20 l.min-1. Oxygen concentration increased and carbon dioxide concentration decreased with increasing oxygen flow. Tidal volume also increased with oxygen flow. The delivered oxygen concentrations were lower than previously reported at all four rates; however, mask function improved with increasing flow up to 20 l. 相似文献
998.
999.
Raymond E. Lenhard Bruce I. Blum Jeffrey M. Sunderland Hayden G. Braine Rein Saral 《Journal of medical systems》1983,7(2):147-174
The Johns Hopkins Oncology Center has developed and maintains a clinical information system to support patient care, education, research, and administrative functions. It operates on a dedicated minicomputer (PDP-II) programmed in MUMPS. Clinical information collected includes patient medical status and laboratory values. Data are used daily in patient care and also in support of retrospective and prospective research. The use of the system to manage a large blood pheresis program and to study and treat infectious disease is described. Administrative functions include patient and personnel scheduling, program evaluation, and projects directed toward control of costs. 相似文献
1000.
Abnormalities of the neonatal brain: MR imaging. Part II. Hypoxic- ischemic brain injury 总被引:3,自引:0,他引:3
Eighty-five infants, 82 of whom were 29-44 weeks postconceptional age, were imaged with a 0.6-T magnet. Eight infants had cerebral infarction. In premature neonates with very water, low-intensity white matter on T1-weighted images, ultrasound was better than both computed tomography and magnetic resonance (MR) imaging in depicting parenchymal changes of infarction or edema. However, after 37 weeks gestation, MR imaging was superior. Cerebral atrophy, present in seven infants, was consistent with subarachnoid space widths of 7 mm or more, or subarachnoid space widths of 5-6 mm with ventricular/brain ratios of 0.36 or greater. Delayed myelination was seen in a total of 18 infants with histories of hypoxic-ischemic insult. MR imaging shows promise in the neonatal period. It facilitates recognition of infarcts in full-term infants and may be used to predict abnormal neurologic outcome in infants who have initial delayed myelination. 相似文献