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1.
Increased production of peroxidation products associated with cardiac operations. Evidence for free radical generation 总被引:7,自引:0,他引:7
D Royston J S Fleming J B Desai S Westaby K M Taylor 《The Journal of thoracic and cardiovascular surgery》1986,91(5):759-766
We investigated the degree and time course of neutrophil sequestration into human lungs during cardiac operations. At the same time, measurement of the concentration of peroxidation products in the plasma was used as an index of oxidant free radical activity. The study was performed in two groups of patients. Group A (n = 11) had studies extending over the entire operative period and showed a highly significant sequestration of neutrophils into the lung, together with a highly significant (p less than 0.001) rise in peroxidation products from 2.8 +/- 0.12 nmol/ml(mean +/- standard error of the mean)before bypass to a peak of 5.05 +/- 0.13 nmol/ml at the end of bypass. As these changes occurred only during the time after release of the aortic cross-clamp, we investigated this period in more detail in a second group of patients (Group B, n = 7). Results from this group showed that significant release of peroxidation products occurred at the same time as pulmonary neutrophil sequestration. This study has produced evidence of increased oxidant activity in the lung associated with cardiac operations. Nevertheless, it is not known whether the neutrophils sequestered into the lung alone induced the increased activity. Similarly, whether neutrophil-derived oxidant species are the sole cause of lung tissue injury remains unproved. 相似文献
2.
Patrick Royston 《Statistics in medicine》1993,12(2):181-184
An easy-to-calculate approximation to the Shapiro—Francia W' test and its P-value is proposed. Its accuracy is sufficient for practical application in samples of size 5 or larger. 相似文献
3.
BACKGROUND AND AIM: Peptic ulcer disease is believed to be less common and less severe as a result of modern medical treatment. We therefore examined changes in the admission rates for patients with duodenal ulcer and gastric ulcer, both emergency (for haemorrhage, perforation or severe pain) and for elective surgery, before and since the introduction of the new advances in therapy. These admission indices reflect disease prevalence and severity. PATIENTS AND METHODS: We identified admission rates during 1972--2000 within the Trent Regional Health Authority, UK (population 4.7 million), from computerised patient information using diagnostic search codes ICD8-10 and expressed as rates per million resident population. Drug expenditure details were obtained from the Department of Health. RESULTS: Emergency admission rates as a whole changed little, a decline in the young being offset by an increase in the elderly. Haemorrhage was the most common reason (approximately 115 per million for duodenal ulcer and 87 for gastric ulcer) throughout [compared with perforation (80 and 21) and pain (90 and 68)]. In contrast, elective surgery has almost disappeared; this reduction began before the introduction of modern treatment. CONCLUSION: Emergency admission rates for duodenal and gastric ulcer for complications or severe pain have fluctuated over the last three decades but with little overall change. In contrast, elective surgery has declined dramatically, as a result of advances in treatment but also from changes in the natural history. 相似文献
4.
Narendra Nathoo Sameer S Nadvi Duncan Royston Mahesh Rana Premjith Gathiram Pratistadevi K Ramdial James R van Dellen 《Journal of clinical neuroscience》2004,11(1):61-65
Patients with acute brain pathology requiring ferromagnetic bio-medical implants for on-going invasive monitoring are largely excluded from the benefits of MRI scanning. We evaluated the behaviour of a thermal diffusion cortical blood flow (TD-CBF) sensor both in vitro (phantom gelatin model) and in vivo environments in a high field strength MRI system.Two baboons underwent cranial subdural implantation of 2 TD-CBF sensors/hemisphere and a single left parietal sensor was implanted subcortically to determine any deleterious effects. Using standard MRI sequences, artefact size, thermal effects, current generation, movement and reliability of recordings were assessed during scanning.The deflection forces were negligible, no observable thermal effects were demonstrated, while wide fluctuations in cerebral blood flow recordings were recorded. Mean image artefact size for implanted sensors was 6 times larger than in vitro. Patients with an implanted TD-CBF sensor may be safely imaged provided the device is disconnected. The MRI images obtained are of an acceptable quality. 相似文献
5.
B D Royston D Royston S B Coade D M Morgan J D Pearson 《Thrombosis and haemostasis》1992,67(1):172-175
The release of prostacyclin (PGI2) and von Willebrand factor (vWF) from human umbilical vein endothelial cells (HUVEC) was examined to determine if aprotinin had any effects on these endothelial cell reactions. These end-points were chosen to indicate if this serine protease inhibitor caused alterations in the control of haemostatic function by endothelium, in the light of the improvement in haemostasis seen in patients given aprotinin therapy at the time of open heart surgery. Stimuli used to promote secretion of prostacyclin and vWF were human alpha-thrombin, histamine, protamine sulphate, poly-L-lysine and phorbol myristate acetate. Aprotinin (30 microMs) had no significant effect on the basal or stimulated release of PGI2 or vWF from HUVEC. 相似文献
6.
The SQA cell line produces Friend leukemia virus that remains leukemogenic after serial passages in vitro. The state of the provirus and its expression were investigated in newborn and adult mouse tissues, using probes specific for ecotropic and xenotropic sequences. Genomic ecotropic and xenotropic sequences were similar in size in spleen and liver of infected and control animals but appear amplified in infected tissues. Expression of these sequences however differed. Several species of xenotropic and ecotropic-specific RNAs were detected in infected spleens, in SQA cells and in the liver of newborn infected animals but were absent in infected adult liver and control tissues. These results suggest that activation and expression of ecotropic and xenotropic endogenous sequences may play a role in pathogenesis of the disease. 相似文献
7.
The sequence of rat hypothalamic pro-thyrotropin releasing hormone, deduced by sequencing of cDNA, in addition to 5 TRH progenitor genitor sequences contains leader, trailer and 4 intervening sequences separated by paired basic amino acid sequences. We have developed radioimmunoassays to synthetic peptides corresponding to portions of these cryptic proTRH sequences and have used these assays to identify and partially characterize proTRH peptides, distinct from TRH, in extracts of rat brain. Two of these peptides correspond closely in size to one intervening sequence and the car☐y-terminal sequence of proTRH. Three other peptides correspond to the intact amino-terminal leader sequence and two peptides formed by a further cleavage of the leader sequence at an internal paired basic amino acid sequence. 相似文献
8.
Administration of antiserum to thyrotropin-releasing hormone (TRH) into the lateral cerebral ventricle of mice significantly attenuated recovery from hyperglycemia induced by treatment with 2-deoxyglucose but had no effect on the plasma glucose of saline-treated mice. TRH, injected centrally together with the anti-TRH antibody, reversed the effect of the antiserum and blocked the development of hyperglycemia. These findings suggest that activation of TRH neurons in the central nervous system may be a physiological event influencing recovery from hyperglycemia. 相似文献
9.
Dear Professor Lian-Sheng Ma Professor Michael Hobsley I have greatly enjoyed reading the account of all you have done towards the development of "The World Journal of Gastroenterology" as described in the article by Zhen-Xi Li in the November st. Issue of the Journal.…… 《World journal of gastroenterology : WJG》2007,13(1):158-158
Dear Professor Lian-Sheng Ma,
Professor Michael Hobsley and I have greatly enjoyed reading the account of all you have done towards the development of "The World Journal of Gastroenterology", as described in the article by Zhen-Xi Li in the November 21st. Issue of the Journal. 相似文献
10.
Julie Hoover‐Fong Adekemi Yewande Alade Michael Ain Ivor Berkowitz Michael Bober Erin Carter Jacqueline Hecht Dan Hoerschemeyer Debra Krakow Gretchen MacCarrick William G. Mackenzie Roberto Mendoza‐Londono Ericka Okenfuss Deirdre Popplewell Cathleen Raggio Kerry Schulze John McGready 《American journal of medical genetics. Part A》2020,182(1):150-161
Hypertension, compounded by obesity, contributes to cardiovascular disease and mortality. Data describing hypertension prevalence in adults with short stature skeletal dysplasias are lacking, perhaps due to poor fit of typical adult blood pressure cuffs on rhizomelic or contracted upper extremities. Through health screening research, blood pressure was measured in short stature adults attending support group meetings and skeletal dysplasia clinics. Blood pressure was measured with a commercially available, narrower adult cuff on the upper and/or lower segment of the arm. Height, weight, age, gender, diagnosis, exercise, and medications were collected. Subjects were classified as normotensive, prehypertensive, or hypertensive for group analysis; no individual clinical diagnoses were made. In 403 short stature adults, 42% were hypertensive (systolic >140, diastolic >90 OR taking antihypertensive medications). For every BMI unit and 1 kg weight increase in males, there was a 9% and an 8% increase, respectively, in the odds of hypertension versus normotension. In females, the increase was 10% and 6%, respectively. In those with achondroplasia, the most common short stature dysplasia, males (n = 106) had 10% greater odds of hypertension versus normotension for every BMI unit and kilogram increase. In females with achondroplasia (n = 128), the odds of hypertension versus normotension was 8% greater for each BMI unit and 7% for each additional kilogram. These data suggest a high population prevalence of hypertension among short stature adults. Blood pressure must be monitored as part of routine medical care, and measuring at the forearm may be the only viable clinical option in rhizomelic short stature adults with elbow contractures. 相似文献