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31.
Pavel-Mititean LM Rowbottom CG Hector CL Partridge M Bortfeld T Schlegel W 《Physics in medicine and biology》2004,49(12):2613-2629
A geometric model is presented which allows calculation of the dosimetric consequences of rectal motion in prostate radiotherapy. Variations in the position of the rectum are measured by repeat CT scanning during the courses of treatment of five patients. Dose distributions are calculated by applying the same conformal treatment plan to each imaged fraction and rectal dose-surface histograms produced. The 2D model allows isotropic expansion and contraction in the plane of each CT slice. By summing the dose to specific volume elements tracked by the model, composite dose distributions are produced that explicitly include measured inter-fraction motion for each patient. These are then used to estimate effective dose-surface histograms (DSHs) for the entire treatment. Results are presented showing the magnitudes of the measured target and rectal motion and showing the effects of this motion on the integral dose to the rectum. The possibility of using such information to calculate normal tissue complication probabilities (NTCP) is demonstrated and discussed. 相似文献
32.
33.
Utility of a multiplex PCR assay for detecting herpesvirus DNA in clinical samples 总被引:4,自引:0,他引:4 下载免费PDF全文
Druce J Catton M Chibo D Minerds K Tyssen D Kostecki R Maskill B Leong-Shaw W Gerrard M Birch C 《Journal of clinical microbiology》2002,40(5):1728-1732
A multiplex PCR was designed to amplify herpes simplex virus types 1 and 2, cytomegalovirus, and varicella-zoster virus DNA present in a diverse range of clinical material. The susceptibility of these viruses to in vivo inhibition by at least one antiviral drug was an important consideration in their inclusion in the multiplex detection system. An aliquot of equine herpesvirus was introduced into each specimen prior to extraction and served as an indicator of potential inhibitors of the PCR and a detector of suboptimal PCR conditions. Compared to virus isolation and immunofluorescence-based antigen detection, the multiplex assay yielded higher detection rates for all viruses represented in the assay. The turnaround time for performance of the assay was markedly reduced compared to those for the other techniques used to identify these viruses. More than 21,000 tests have been performed using the assay. Overall, the multiplex PCR enabled the detection of substantially increased numbers of herpesviruses, in some cases in specimens or anatomical sites where previously they were rarely if ever identified using traditional detection methods. 相似文献
34.
A comparison of research general practices and their patients with other practices--a cross-sectional survey in Trent. 下载免费PDF全文
Vicky Hammersley Julia Hippisley-Cox Andrew Wilson Mike Pringle 《The British journal of general practice》2002,52(479):463-468
BACKGROUND: When interpreting results of studies undertaken by research networks we need to know how representative volunteer practices and their registered patients are of the total population of practices and patients in their locality. AIM: To compare the following in research and non-research general practices in one region: practice and population demography, morbidity and mortality, selected performance indicators, and health outcomes. DESIGN OF STUDY: Cross-sectional survey. SETTING: Sixty-six Trent Focus Collaborative Research Network general practices and 749 other general practices in Trent, United Kingdom. METHOD: Practice characteristics and GP contract data were obtained from the NHS Executive, Quarry House, Leeds. The Trent Regional NHS Hospital Admission Database was searched to identify all relevant admissions to hospital from all practices between 1 April 1993 and 31 March 1997. Ward-linked data on cancer were obtained from the Trent Cancer Registry. RESULTS: Of the 815 general practices in Trent Region in the study period, 66 (8%) were in the Trent Focus network. They were more likely to be involved in training GPs and to have a female partner. They tended to be larger, with fewer single-handed doctors and younger GPs. Network practices prescribed a higher proportion of generics (median % prescribed/practice = 70%, versus 51%, Mann-Whitney U = 1615, P<0.0001). There were no clinically important differences between hospital admission rates between the two groups or waiting times for surgical procedures. There was no difference in the incidence of cancer and standardised mortality ratios related to the electoral wards of the GP surgery. CONCLUSION: Although there were differences in practice structure and some aspects of performance, we found no important differences in the demography of registered patients, nor in morbidity, mortality, or access to or use of secondary care. 相似文献
35.
Soya protein antibodies in man: their occurrence and possible relevance in coeliac disease. 下载免费PDF全文
M R Haeney B J Goodwin M E Barratt N Mike P Asquith 《Journal of clinical pathology》1982,35(3):319-322
Circulating antibodies to soya-derived protein antigens have been measured in patients with duodenitis, Crohn's disease, ulcerative colitis and coeliac disease. Significantly raised antibody titres were found frequently in the coeliac group, particularly those patients showing a suboptimal response to a gluten-free diet, but rarely in subjects with other gastrointestinal diseases. Antisoya activity was not necessarily accompanied by antibodies to other common dietary antigens. We suggest that some coeliacs may have an associated dietary soya sensitivity which could adversely influence their response to gluten withdrawal. 相似文献
36.
Zhang B van Adel BA Gabriele J Duong M Henry P Ball AK Mishra RK 《Journal of chemical neuroanatomy》2002,24(1):2248-48
Catecholamine regulated protein 40 (CRP40) has been shown to be expressed in the central nervous system (CNS) of several mammalian species where it may function in a similar manner to members of the heat shock protein (HSP) family. Immunohistochemical and immunoblotting techniques were utilized to investigate whether CRP40 is expressed in normal rat retinas. In addition, changes in CRP40 expression were studied following optic nerve transection. The immunohistochemical results showed that CRP40 is expressed in the normal rat retina. The protein was found to be highly expressed in the ganglion cell layer (GCL), the inner nuclear layer (INL) and the outer plexiform layer (OPL). In addition, a low level of CRP40 was found in the inner plexiform layer (IPL), and in the inner segment layer (ISL). No expression was found in the outer nuclear layer (ONL) of normal rat retina. The immunoblotting results show that CRP40 expression decreased in a time-dependent fashion after the optic nerve transection. This decrease indicates that the expression of CRP40 is dependent on the neuron's normal physiological state and that it plays an important function in physiological and pathological conditions in the retina. 相似文献
37.
Willis F Graff-Radford N Pinto M Lawson L Adamson J Epstein D Parfitt F Hutton M O'Brien PC 《Journal of the National Medical Association》2003,95(1):71-76
Through its role in lipid metabolism, Apolipoprotein epsilon4 (ApoE4) may affect "brain repair" in stroke, brain hemorrhage, Alzheimer's disease, and other brain injury syndromes for which African Americans may have greater morbidity and mortality. Cross-cultural evaluations of these and other genetic factors may provide insight on possible ethnic differences in risk of morbidity to acute central nervous system (CNS) injury and chronic neurodegenerative processes. As an initial step toward expanding knowledge of ApoE allele frequencies for persons of African descent, we compared ApoE genotype of a group of 70 young Ugandans to 59 (subset of a larger group of 342 African Americans of all ages) age-matched African Americans and to published frequencies for Caucasians and Asians. We found that the ApoE4 and epsilon2 alleles are more frequent in Ugandans (U) than Caucasians (C) or Asians (A) with corresponding alleles showing significant elevations of epsilon2 (U 15.71%, C 8.40%, A 4.20%) and 14 (U 25%, C 13.70%, A 8.90%) (p < .001). Comparing the differences between Ugandans and age-appropriate African Americans (AA) was not statically significant, but this outcome may be due to small sample size. These results provide the only published ApoE frequencies for Ugandans and the complete set of data provides the largest published community group of ApoE frequencies for African Americans. 相似文献
38.
Taams LS Vukmanovic-Stejic M Smith J Dunne PJ Fletcher JM Plunkett FJ Ebeling SB Lombardi G Rustin MH Bijlsma JW Lafeber FP Salmon M Akbar AN 《European journal of immunology》2002,32(6):1621-1630
Anergic/suppressive CD4+CD25+ T cells have been proposed to play an important role in the maintenance of peripheral tolerance. Here we demonstrate that in humans these cells suppress proliferation to self antigens, but also to dietary and foreign antigens. The suppressive CD4+CD25+ T cells display a broad usage of the T cell receptor Vbeta repertoire,suggesting that they recognize a wide variety of antigens. They reside in the primed/memory CD4+CD45RO+CD45RB(low) subset and have short telomeres, indicating that these cells have the phenotype of highly differentiated CD4+ T cells that have experienced repeated episodes of antigen-specific stimulation in vivo. This suggests that anergic/suppressive CD4+CD25+ T cells may be generated in the periphery as a consequence of repeated antigenic encounter. This is supported by the observation that highly differentiated CD4+T cells can be induced to become anergic/suppressive when stimulated by antigen presented by non-professional antigen-presenting cells. We suggest that besides being generated in the thymus, CD4+CD25+ regulatory T cells may also be generated in the periphery. This would provide a mechanism for the generation of regulatory cells that induce tolerance to a wide array of antigens that may not be encountered in the thymus. 相似文献
39.
Development and characterisation of neutralising monoclonal antibody to the SARS-coronavirus 总被引:7,自引:0,他引:7
Berry JD Jones S Drebot MA Andonov A Sabara M Yuan XY Weingartl H Fernando L Marszal P Gren J Nicolas B Andonova M Ranada F Gubbins MJ Ball TB Kitching P Li Y Kabani A Plummer F 《Journal of virological methods》2004,120(1):87-96
There is a global need to elucidate protective antigens expressed by the SARS-coronavirus (SARS-CoV). Monoclonal antibody reagents that recognise specific antigens on SARS-CoV are needed urgently. In this report, the development and immunochemical characterisation of a panel of murine monoclonal antibodies (mAbs) against the SARS-CoV is presented, based upon their specificity, binding requirements, and biological activity. Initial screening by ELISA, using highly purified virus as the coating antigen, resulted in the selection of 103 mAbs to the SARS virus. Subsequent screening steps reduced this panel to seventeen IgG mAbs. A single mAb, F26G15, is specific for the nucleoprotein as seen in Western immunoblot while five other mAbs react with the Spike protein. Two of these Spike-specific mAbs demonstrate the ability to neutralise SARS-CoV in vitro while another four Western immunoblot-negative mAbs also neutralise the virus. The utility of these mAbs for diagnostic development is demonstrated. Antibody from convalescent SARS patients, but not normal human serum, is also shown to specifically compete off binding of mAbs to whole SARS-CoV. These studies highlight the importance of using standardised assays and reagents. These mAbs will be useful for the development of diagnostic tests, studies of SARS-CoV pathogenesis and vaccine development. 相似文献
40.
Mike Fitzpatrick 《The British journal of general practice》2008,58(548):216-217