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61.
Donald B. Penzien PhD ; Frank Andrasik PhD ; Brian M. Freidenberg PhD ; Timothy T. Houle PhD ; Alvin E. Lake III PhD; Gay L. Lipchik PhD ; Kenneth A. Holroyd PhD ; Richard B. Lipton MD ; Douglas C. McCrory MD ; Justin M. Nash PhD ; Robert A. Nicholson PhD ; Scott W. Powers PhD ABPP ; Jeanetta C. Rains PhD ; David A. Wittrock PhD 《Headache》2005,45(S2):S110-S132
Guidelines for design of clinical trials evaluating behavioral headache treatments were developed to facilitate production of quality research evaluating behavioral therapies for management of primary headache disorders. These guidelines were produced by a Workgroup of headache researchers under auspices of the American Headache Society. The guidelines are complementary to and modeled after guidelines for pharmacological trials published by the International Headache Society, but they address methodologic considerations unique to behavioral and other nonpharmacological treatments. Explicit guidelines for evaluating behavioral headache therapies are needed as the optimal methodology for behavioral (and other nonpharmacologic) trials necessarily differs from the preferred methodology for drug trials. In addition, trials comparing and integrating drug and behavioral therapies present methodological challenges not addressed by guidelines for pharmacologic research. These guidelines address patient selection, trial design for behavioral treatments and for comparisons across multiple treatment modalities (eg, behavioral vs pharmacologic), evaluation of results, and research ethics. Although developed specifically for behavioral therapies, the guidelines may apply to the design of clinical trials evaluating many forms of nonpharmacologic therapies for headache. 相似文献
62.
Exercise rapidly increases eukaryotic elongation factor 2 phosphorylation in skeletal muscle of men 总被引:11,自引:6,他引:5
Adam J. Rose Christa Broholm Kristian Kiillerich Stephen G. Finn Christopher G. Proud Mark H. Rider Erik A. Richter Bente Kiens 《The Journal of physiology》2005,569(1):223-228
Protein synthesis in skeletal muscle is known to decrease during contractions but the underlying regulatory mechanisms are unknown. Here, the effect of exercise on skeletal muscle eukaryotic elongation factor 2 (eEF2) phosphorylation, a key component in protein translation machinery, was examined. Eight healthy men exercised on a cycle ergometer at a workload eliciting ∼67% peak pulmonary oxygen consumption with skeletal muscle biopsies taken from the vastus lateralis muscle at rest as well as after 1, 10, 30, 60 and 90 min of exercise. In response to exercise, there was a rapid (i.e. < 1 min) 5- to 7-fold increase in eEF2 phosphorylation at Thr56 that was sustained for 90 min of continuous exercise. The in vitro activity of skeletal muscle eEF2 kinase was not altered by exercise indicating that the increased activity of eEF2 kinase to eEF2 is not mediated by covalent mechanisms. In support of this, the increase in AMPK activity was temporally unrelated to eEF2 phosphorylation. However, skeletal muscle eEF2 kinase was potently activated by Ca2 + –calmodulin in vitro , suggesting that the higher eEF2 phosphorylation in working skeletal muscle is mediated by allosteric activation of eEF2 kinase by Ca2 + signalling via calmodulin. Given that eEF2 phosphorylation inhibits eEF2 activity and mRNA translation, these findings suggest that the inhibition of protein synthesis in contracting skeletal muscle is due to the Ca2 + -induced stimulation of eEF2 kinase. 相似文献
63.
64.
Brain abscess in the 1980s 总被引:1,自引:0,他引:1
F E Donald J L Firth I M Holland D T Hope P Ispahani J A Punt 《British journal of neurosurgery》1990,4(4):265-271
Brain abscess was reviewed in 24 patients admitted to University Hospital, Nottingham over a period of 3 years. Chronic ear infection was the most common predisposing factor, but in 11 patients the focus of infection remained unknown. CT scanning, carried out in all patients, was negative in one patient with clinical signs of meningitis. Polymicrobial and anaerobic infections were common. Actinomyces species were isolated in mixed culture from seven patients; in five the abscess was located in the cerebellum. Therapy was most often a combination of surgical drainage and antimicrobial therapy with beta-lactam agents and metronidazole. Evidence suggests that cefotaxime may offer a suitable alternative to chloramphenicol and benzylpenicillin in the treatment of brain abscess. 相似文献
65.
E H Rose 《Annals of plastic surgery》1990,24(5):451-454
Impalement injuries to the upper extremity are rare. A case is described of penetration of a 10 x 3.5-inch fence post into the left shoulder of a 16-year-old boy, pinning the shoulder to the chest wall. Sequelae of potential serious brachioplexus, vascular, and intrathoracic injuries are reviewed. The author presents a systematic treatment approach to the assessment, extrication, and microneurovascular repair of damaged structures, and to soft tissue reconstruction following massive foreign body injuries. 相似文献
66.
Selection for donor-specific cytotoxic T lymphocytes within the allografted human heart. 总被引:3,自引:0,他引:3
Lymphocytes were cultured from cardiac biopsies following heart transplantation using interleukin-2-conditioned medium. Using the technique of limiting dilution analysis the frequency of donor specific cytotoxic T lymphocytes was measured in cells cultured from biopsies and compared with that in peripheral blood lymphocytes taken at the same time as the biopsy. The graft cell population showed a considerably higher frequency of donor-specific CTL when compared with the PBL. CTL frequencies in the graft cells were always higher against the donor than against third-party cells. These data demonstrate that there was either selective sequestration or selective expansion of donor-reactive T cells in the heart following cardiac transplantation. These results emphasize the need to investigate more closely the events occurring in the heart, and may explain the lack of specificity and sensitivity in immune monitoring (IM) or cytoimmune monitoring (CIM) seen in many centers. 相似文献
67.
Homologous testis transplantation in dogs 总被引:4,自引:0,他引:4
Evert J. Barten Hayrabet Garybian Pieter J. Klopper Donald W. W. Newling 《Transplant international》1997,10(5):362-368
There is growing interest in the possible use of homologous testis transplantation for the treatment of anorchia and male
infertility. In order to test the surgical and immunological feasibility of this therapy, three series of experimental studies
of homologous testis transplantation were carried out in dogs. In the first pilot study, four beagles from the same litter
were transplanted using microsurgical techniques for end-to-end anastomosis of the testicular vessels and the vas deferens.
These dogs received cyclosporin A (CyA) for 3 months after transplantation. The longest functional graft survival in this
series was 163 days, strongly suggesting that long-term survival of a homologously transplanted testis graft is possible.
A second series of operations was performed on ten mongrel dogs. The same surgical technique was employed and the series was
divided into three groups.
Group 1 received CyA monotherapy, group 2 a combination of CyA and prednisolone, and group 3 received no immunosuppression.
The average graft survival time in this series was 18 days, significantly less than the 71 days in the first series. The dogs
in group 2, however, had graft survival times that were three times longer than those in the other two groups, suggesting
that CyA in combination with prednisolone yields the best graft survival. In the third series, five littermates received a
testis graft after castration. Immunosuppression was achieved by administration of CyA and prednisolone for 3 months. In three
out of five animals, the graft survived until the immunosuppressive therapy was suspended. Histological biopsies of the graft
3 months after transplantation showed the same maturation of sperm cells as in the control testis of the same dog. The results
of the last series suggest that long-term survival of homologously transplanted testis grafts in dogs is, indeed, possible
with the aid of CyA and prednisolone.
Received: 14 August 1996 Received after revision: 21 March 1997 Accepted: 24 April 1997 相似文献
68.
Cytogenetically visible gene amplification structures can consist of arrays of amplicons presumably formed by secondary “rearrangements” following amplicon formation. The structural evolution of gene amplification sites in tumor cells suggests that complex secondary structures may have some selective advantage in the tumor cell environment. Although secondary amplicon rearrangements are a hallmark of the gene amplification process, little is known about the mechanics of this process. COLO320 neuroendocrine tumor cells carry two different types of amplified MYC oncogene sequences, one type with an intact MYC gene and the other with a rearranged “chimeric” MYC gene. We have studied various clonal subpopulations of COLO320 cells and identified regions within and downstream of the MYC locus that are unique to each amplicon type. Using double-label fluorescence in situ hybridization with DNA probes unique to each amplicon type, we have observed that both chromosomal and extrachromosomal MYC amplicon arrays in COLO320 cells frequently consist of heterogeneous mixtures of each MYC amplicon type. Our results suggest that the two MYC amplicon types of COLO320 cells were formed simultaneously but independently, and that double minute chromosomes observed in COLO320 cells were formed by intermolecular homologous recombination secondary to amplicon formation. © 1993 Wiley-Liss, Inc. 相似文献
69.
Production of epidermal growth factor and transforming growth factor-alpha by the androgen-responsive LNCaP human prostate cancer cell line 总被引:2,自引:0,他引:2
Epidermal growth factor (EGF)-related polypeptides may be involved in the growth of human prostate cancer cells, and in the androgen stimulation of hormone-responsive prostatic carcinomas. We have shown that androgen-responsive LNCaP cells, like the autonomous DU 145 human prostate cancer cell line, synthesize and secrete EGF and related polypeptides, including immunoreactive transforming growth factor-alpha (TGF-alpha). As determined by radioimmunoassay, intracellular EGF levels were approximately 100 times those of TGF-alpha, but together these accounted for less than half of the total EGF-like polypeptides detected in a radioreceptor assay. Although LNCaP cell growth was stimulated by dihydrotestosterone (DHT), there was no evident effect on immunoreactive EGF levels in the medium after correction for cell number. Moreover, metabolic labeling experiments showed no effect of the androgen on EGF synthesis by LNCaP cells. Gel filtration chromatography of conditioned medium showed both high molecular weight species and the mature 6,000 dalton form of immunoreactive EGF. We conclude that although LNCaP prostate cancer cell growth is stimulated by DHT, it is unlikely that it is mediated directly via increased EGF synthesis by the tumor cells. 相似文献
70.
Hilary Eadon Marlene Rose Richard O'Neill Neil Leaver Magdi Yacoub 《Transplant international》1995,8(1):35-40
Pharmacokinetic profiles were obtained for 16 heart or lung recipients following the administration of identical doses of cyclosporin as oral solution and capsules on consecutive days. A comparison of pharmacokinetic parameters (AUC, Cmax, Cmin and tmax) showed that there were no significant differences between the two formulations except for the tmax, which was significantly longer for the capsules. The mean variation in day-to-day trough levels produced by the two different forms was 25.6%. A retrospective study was carried out of consecutive cyclosporin levels in patients at steady state on oral solution. The mean variation in day-to-day trough levels was 32.3%. This was not significantly different from the variation in consecutive trough levels seen in the oral solution/capsule comparison. This study shows that cyclosporin capsules can be substituted for oral solution without causing acute changes in cyclosporin blood levels, and that the pharmacokinetics of the two formulations are similar.This work was carried out in partial fulfillment of the requirements for the Master of Science Degree in Clinical Pharmacy, University of London 相似文献